Supporting Research

Below we provide a bibliography of research that builds the foundation of  “Biodiversity Islands.”


Economic Benefits

-Evaluating Economic Value

An overview of the total global value of ecosystem services….

Adamowicz, W., Calderon-Etter, L., Entem, A., Fenichel, E.P., Hall, J.S., Lloyd-Smith, P., Ogden, F.L., Regina, J.A., Rad, M.R. and Stallard, R.F., 2019. Assessing ecological infrastructure investments. Proceedings of the National Academy of Sciences, p.201802883.
Abstract: Conventional markets can underprovide ecosystem services. Deliberate creation of a market for ecosystem services [e.g., a payments for ecosystem services (PES) scheme] can close the gap. The new ecosystem service market alters behaviors and quantities of ecosystem service provided and reveals prices for the ecosystems service: a market-clearing equilibrium. Assessing the potential for PES programs, which often act as ecological infrastructure investment mechanisms, requires forecasting the market-clearing equilibrium. Forecasting the equilibrium is complicated, especially at relevant social and ecological scales. It requires greater disciplinary integration than valuing ecosystem services or computing the marginal cost of making a land-use change to produce a service. We conduct an ex ante benefit–cost assessment and forecast market-clearing prices and quantities for ecological infrastructure investment contracts in the Panama Canal Watershed. The Panama Canal Authority could offer contracts to private farmers to change land use to increase dry-season water flow and reduce sedimentation. A feasible voluntary contracting system yields a small program of about 1,840 ha of land conversion in a 279,000-ha watershed and generates a 4.9 benefit–cost ratio. Physical and social constraints limit market supply and scalability. Service delays, caused by lags between the time payments must be made and the time services stemming from ecosystem change are realized, hinder program feasibility. Targeting opportunities raise the benefit–cost ratio but reduce the hectares likely to be converted. We compare and contrast our results with prior state-of-the-art assessments on this system.
Costanza, R., de Groot, R., Sutton, P., van der Ploeg, S., Anderson, S.J., Kubiszewski, I., Farber, S. and Turner, R.K., 2014. Changes in the global value of ecosystem services. Global environmental change, 26, pp.152-158.
Abstract: In 1997, the global value of ecosystem services was estimated to average $33 trillion/yr in 1995 $US ($46 trillion/yr in 2007 $US). In this paper, we provide an updated estimate based on updated unit ecosystem service values and land use change estimates between 1997 and 2011. We also address some of the critiques of the 1997 paper. Using the same methods as in the 1997 paper but with updated data, the estimate for the total global ecosystem services in 2011 is $125 trillion/yr (assuming updated unit values and changes to biome areas) and $145 trillion/yr (assuming only unit values changed), both in 2007 $US. From this we estimated the loss of eco-services from 1997 to 2011 due to land use change at $4.3–20.2 trillion/yr, depending on which unit values are used. Global estimates expressed in monetary accounting units, such as this, are useful to highlight the magnitude of eco-services, but have no specific decision-making context. However, the underlying data and models can be applied at multiple scales to assess changes resulting from various scenarios and policies. We emphasize that valuation of eco-services (in whatever units) is not the same as commodification or privatization. Many eco-services are best considered public goods or common pool resources, so conventional markets are often not the best institutional frameworks to manage them. However, these services must be (and are being) valued, and we need new, common asset institutions to better take these values into account.


An updated global value of ecosystem services….

Costanza, R., de Groot, R., Braat, L., Kubiszewski, I., Fioramonti, L., Sutton, P., Farber, S. and Grasso, M., 2017. Twenty years of ecosystem services: How far have we come and how far do we still need to go?. Ecosystem Services, 28, pp.1-16.
Abstract: It has been 20 years since two seminal publications about ecosystem services came out: an edited book by Gretchen Daily and an article in Nature by a group of ecologists and economists on the value of the world’s ecosystem services. Both of these have been very highly cited and kicked off an explosion of research, policy, and applications of the idea, including the establishment of this journal. This article traces the history leading up to these publications and the subsequent debates, research, institutions, policies, on-the-ground actions, and controversies they triggered. It also explores what we have learned during this period about the key issues: from definitions to classification to valuation, from integrated modelling to public participation and communication, and the evolution of institutions and governance innovation. Finally, it provides recommendations for the future. In particular, it points to the weakness of the mainstream economic approaches to valuation, growth, and development. It concludes that the substantial contributions of ecosystem services to the sustainable wellbeing of humans and the rest of nature should be at the core of the fundamental change needed in economic theory and practice if we are to achieve a societal transformation to a sustainable and desirable future.

Private Sector Investment in Biodiversity Conservation

Credit Suisse, World Wildlife Fund, and McKinsey & Company. 2014. Conservation finance: Moving beyond donor funding toward an investor-driven approach. Retrieved 1 November, 2018, from
Valuable ecosystems are today undergoing rapid degradation and depletion in many parts of the world. Natural capital and the services that ecosystems provide are still poorly understood and rarely monitored. Unlike in the case of traditional commodities, the value of these natural resources is not recognized by today’s markets. It is, however, crucial that we understand the interrelationship between environmental quality and economic profitability. This information needs to be integrated into macroeconomic analysis and included in decision-making processes in the areas of financing and investment. To preserve the health of natural ecosystems, a significantly larger amount of capital investment is required than the sums currently being allocated to conservation. Private sector investment is needed, not to replace but to supplement traditional sources of conservation capital such as public funding or philanthropy, which have been impacted by the global economic downturn. Against this backdrop, WWF and Credit Suisse have joined forces in the area of conservation finance to identify the conditions needed to attract and redirect private capital toward conservation.
This report shows that there are many unexploited private sector investment opportunities to increase conservation finance and deliver maximum conservation impacts while, at the same time, generating returns for investors. In order to develop appropriate financing structures and ensure that private sector conservation finance results in measurable conservation outcomes, financial institutions and non-governmental organizations must experiment and define their respective roles and approaches. If both sides concentrate on their main areas of expertise – with banks focusing on the alignment of capital resources, risks, and maturities, while NGOs identify measures to protect the natural environment – we can create a new opportunity for collaboration that will help to preserve natural capital for future generations. Provided it delivers measurable results, investor-driven conservation finance can create powerful incentives for truly sustainable development.


Analyzing valuation of ecosystem services through various spacial scales and how these scales interact among various stakeholders….

Hein, Lars & Van Koppen, Christianus & Groot, Rudolf & van Ierland, Ekko. (2006). Spatial Scales, Stakeholders and the Valuation of Ecosystem Services. Ecological Economics. 57. 209-228. 10.1016/j.ecolecon.2005.04.005.
Abstract: Since the late 1960s, the valuation of ecosystem services has received ample attention in scientific literature. However, to date, there has been relatively little elaboration of the various spatial and temporal scales at which ecosystem services are supplied. This paper analyzes the spatial scales of ecosystem services, and it examines how stakeholders at different spatial scales attach different values to ecosystem services. The paper first establishes an enhanced framework for the valuation of ecosystem services, with specific attention for stakeholders. The framework includes a procedure to assess the value of regulation services that avoids double counting of these services. Subsequently, the paper analyses the spatial scales of ecosystem services: the ecological scales at which ecosystem services are generated, and the institutional scales at which stakeholders benefit from ecosystem services. On the basis of the proposed valuation framework, we value four selected ecosystem services supplied by the De Wieden wetlands in The Netherlands, and we analyze how these services accrue to stakeholders at different institutional scales. These services are the provision of reed for cutting, the provision of fish, recreation, and nature conservation. In the De Wieden wetland, reed cutting and fisheries are only important at the municipal scale, recreation is most relevant at the municipal and provincial scale, and nature conservation is important in particular at the national and international level. Our analysis shows that stakeholders at different spatial scales can have very different interests in ecosystem services, and we argue that it is highly important to consider the scales of ecosystem services when valuation of services is applied to support the formulation or implementation of ecosystem management plans.

Status and trends in ecosystem services.

Salzman, J., G. Bennett, N. Carroll, A. Goldstein, and M. Jenkins. 2018. The global status and trends of Payments for Ecosystem Services. Nature Sustainability 1: 136–144.
Abstract: Recent decades have witnessed a considerable increase in Payments for Ecosystem Services (PES)—programmes that exchange value for land management practices intended to provide or ensure ecosystem services—with over 550 active programmes around the globe and an estimated US$36–42 billion in annual transactions. PES represent a recent policy instrument with often very different programmes operating at local, regional and national levels. Despite the growth of these programmes, comprehensive and reliable data have proven difficult to find. This Analysis provides an assessment of the trends and current status of PES mechanisms—user-financed, government-financed and compliance—across the domains of water, biodiversity, and forest and land-use carbon around the world. We report the various dimensions of growth over the past decade (number of programmes, geographical spread, dollar value) to understand better the range of PES mechanisms over time and to examine which factors have contributed to or hindered growth. Four key features stand out for scaling up PES: motivated buyers, motivated sellers, metrics and low-transaction-cost institutions. A unique dataset of over 550 programmes of Payments for Ecosystem Services (PES) worldwide, grouped into water, forest- and land-use carbon, and biodiversity programmes, is used to assess the trends and the current status of such policy instruments.


Microeconomic considerations for ecosystem and biodiversity conservation through the value of ecosystem services….

Naidoo, Robin, and Taylor H. Ricketts. “Mapping the economic costs and benefits of conservation.” PLoS biology 4.11 (2006): e360.
Abstract: Resources for biodiversity conservation are severely limited, requiring strategic investment. Understanding both the economic benefits and costs of conserving ecosystems will help to allocate scarce dollars most efficiently. However, although cost-benefit analyses are common in many areas of policy, they are not typically used in conservation planning. We conducted a spatial evaluation of the costs and benefits of conservation for a landscape in the Atlantic forests of Paraguay. We considered five ecosystem services (i.e., sustainable bushmeat harvest, sustainable timber harvest, bioprospecting for pharmaceutical products, existence value, and carbon storage in aboveground biomass) and compared them to estimates of the opportunity costs of conservation. We found a high degree of spatial variability in both costs and benefits over this relatively small (~3,000 km2) landscape. Benefits exceeded costs in some areas, with carbon storage dominating the ecosystem service values and swamping opportunity costs. Other benefits associated with conservation were more modest and exceeded costs only in protected areas and indigenous reserves. We used this cost-benefit information to show that one potential corridor between two large forest patches had net benefits that were three times greater than two otherwise similar alternatives. Spatial cost-benefit analysis can powerfully inform conservation planning, even though the availability of relevant data may be limited, as was the case in our study area. It can help us understand the synergies between biodiversity conservation and economic development when the two are indeed aligned and to clearly understand the trade-offs when they are not.


Proper valuation of ecosystem and biological conservation through various lenses….

Pagiola, Stefano; von Ritter, Konrad; Bishop, Joshua. Assessing the Economic Value of Ecosystem Conservation. Environment Department Papers. Environmental Economics 2004. World Bank, Washington, DC. © World Bank. License: CC BY 3.0 IGO.”
Executive Summary:  “Valuation studies have considerably increased our knowledge of the value of ecosystems. Their usefulness has often been undermined, however, by failure to properly frame them so as to address the specific question of interest. Unfortunately, environmental advocates in the media, government, business, and civil society have often seized on impressive but sometimes unsound valuation results and used them indiscriminately, and often inappropriately. Valuation is not a single activity, and the seemingly simple question ‘how valuable is an ecosystem?’ can be interpreted in many different ways. It could be interpreted as asking about the value of the current flow of benefits provided by that ecosystem, for example, or about the value of future flows of benefits. It could also be asking about the value of conserving that ecosystem rather than converting it to some other use. These interpretations of the question are often treated as being synonymous, but they are in fact very different questions, and the answer to one will not be correct as an answer to the other. This paper seeks to clarify how valuation should be conducted to answer specific policy questions. In particular, it looks at how valuation should be used to examine four distinct aspects of the value of ecosystems.


The overall economic value of environmental benefits that result from biodiversity. What can be lost vs. what can be gained through biodiversity conservation efforts…..

Pimentel, David, et al. “Economic and environmental benefits of biodiversity.” BioScience 47.11 (1997): 747-757.
Summary: This study explores the economic and environmental value of biodiversity.  The 1997 estimate of value from biodiversity is $300 Billion. The crucial connection between economic health and healthy biodiversity is described in detail through this pivotal article.

Beyond Economics

The ineptitude and and inadequacy of valuing biodiversity through economic valuations.

Maier, D.S., 2017. Should biodiversity and nature have to earn their keep? What it really means to bring environmental goods into the marketplace. Ambio, pp.1-16.
Abstract: Pursuit of economic gain has sponsored much of our planet’s despoliation. Yet conservation increasingly operates as an economic sector that markets biodiversity, ecosystems, and nature as natural capital, service provider, or option value. This essay first elucidates what basic moral theory says about the principle that the goodness of biodiversity and nature is largely economic. It explains why economic valuations may be morally unimportant, inapt for environmental goods, and subversive of more important ideals. It also shows why neither econometric notions of option value nor Daniel Faith’s qualitative one credibly applies. The essay then turns to what an economic conception of goodness implies for conservation practice. It refers to two prominent conservation organizations, whose conservation principles match the market-based ones of the World Business Council on Sustainable Development’s. The environmental record of the latter organization’s practices according to these principles predicts what their adoption for conservation entails.

Community Led Action

Community Based Conservation (CBC) the fusion of conservation and development for the benefit of the whole.

Berkes, Fikret. Rethinking Community Based Conservation Conservation biology 18.3 (2004): 621-630.
Abstract: Community-based conservation (CBC) is based on the idea that if conservation and development could be simultaneously achieved, then the interests of both could be served. It has been controversial because community development objectives are not necessarily consistent with conservation objectives in a given case. I examined CBC from two angles. First, CBC can be seen in the context of paradigm shifts in ecology and applied ecology. I identified three conceptual shifts—toward a systems view, toward the inclusion of humans in the ecosystem, and toward participatory approaches to ecosystem management—that are interrelated and pertain to an understanding of ecosystems as complex adaptive systems in which humans are an integral part. Second, I investigated the feasibility of CBC, as informed by a number of emerging interdisciplinary fields that have been pursuing various aspects of coupled systems of humans and nature. These fields  common property, traditional ecological knowledge, environmental ethics, political ecology, and environmental history provide insights for CBC. They may contribute to the development of an interdisciplinary conservation science with a more sophisticated understanding of social-ecological interactions. The lessons from these fields include the importance of cross-scale conservation, adaptive comanagement, the question of incentives and multiple stakeholders, the use of traditional ecological knowledge, and development of a cross-cultural conservation ethic.


“Church Forests” in Ethiopia provide a sanctuary for Biodiversity.

“If you see a forest in Ethiopia, you know there is very likely to be a church in the middle, says Alemayehu Wassie. Wassie, a forest ecologist, has spent the past decade on a mission: preserving, documenting and protecting the unique biodiversity in pockets of forest that surround Ethiopia’s orthodox churches.
These small but fertile oases — which number around 35,000 and are dotted across the country — are some of the last remaining scraps of the tall, lush natural forests that once covered Ethiopia, and which, along with their biodiversity, have all but disappeared.”
Sacred groves as a tool for biodiversity conservation…
Bhagwat, S.A. and Rutte, C., 2006. Sacred groves: potential for biodiversity management. Frontiers in Ecology and the Environment, 4(10), pp.519-524.
Abstract: Conventional markets can underprovide ecosystem services. Deliberate creation of a market for ecosystem services [e.g., a payments for ecosystem services (PES) scheme] can close the gap. The new ecosystem service market alters behaviors and quantities of ecosystem service provided and reveals prices for the ecosystems service: a market-clearing equilibrium. Assessing the potential for PES programs, which often act as ecological infrastructure investment mechanisms, requires forecasting the market-clearing equilibrium. Forecasting the equilibrium is complicated, especially at relevant social and ecological scales. It requires greater disciplinary integration than valuing ecosystem services or computing the marginal cost of making a land-use change to produce a service. We conduct an ex ante benefit–cost assessment and forecast market-clearing prices and quantities for ecological infrastructure investment contracts in the Panama Canal Watershed. The Panama Canal Authority could offer contracts to private farmers to change land use to increase dry-season water flow and reduce sedimentation. A feasible voluntary contracting system yields a small program of about 1,840 ha of land conversion in a 279,000-ha watershed and generates a 4.9 benefit–cost ratio. Physical and social constraints limit market supply and scalability. Service delays, caused by lags between the time payments must be made and the time services stemming from ecosystem change are realized, hinder program feasibility. Targeting opportunities raise the benefit–cost ratio but reduce the hectares likely to be converted. We compare and contrast our results with prior state-of-the-art assessments on this system.


Ceperley, N., Montagnini, F. and Natta, A., 2010. Significance of sacred sites for riparian forest conservation in Central Benin. Bois et Forêts des Tropiques, 303(1), pp.5-23.
Íbú ódó, or sacred pools or points in the river, are generally respected by Tchabè communities along the Ouèmé and Okpara Rivers of Central Benin (West Africa). Íbú ódó are governed by rules that may influence conservation practices, including bans on fish poisoning, over-fishing and pollution and discouragement of cattle grazing and cultivation in their vicinity. Riparian forest structure and diversity was examined in three sites adjacent to sacred pools as well as in riparian areas adjacent to various land uses in the region. Diversity in riparian forest tree species was highest in areas adjacent to sacred forests, while tree basal area was larger in areas adjacent to village uses or to sacred lands. The most remote site had the most diverse riparian forest with the largest basal area. Concurrent interviews with elders and hunting chiefs revealed the significant cultural importance of sacred pools and riparian resources. Íbú ódó were respected not only by resident populations but also by migrants to the area. Riparian forests were valued for their many ecosystem services including soil fertility and their functions as windbreaks and hunting grounds. Íbú ódó should be incorporated into a long-term management strategy for the Ouémé River basin that will prevent the destruction of vegetation while conserving riparian forests. This would be crucial to flood control and biodiversity conservation in central Benin.
Gadgil, M., F. Berkes, and C. Folke. 1993. Indigenous knowledge for biodiversity conservation. Ambio 151-156.
Abstract: Indigenous peoples with a historical continuity of resource- use practices often possess a broad knowledge base of the behavior of complex ecological systems in their own localities. This knowledge has accumulated through a long series of observations transmitted from generation to generation. Such “diachronic” observations can be of great value and complement the “synchronic” observations on which western science is based. Where indigenous peoples have depended, for long periods of time, on local environments for the provision of a variety of resources, they have developed a stake in conserving, and in some cases, enhancing, biodiversity. They are aware that biological diversity is a crucial factor in generating the ecological services and natural resources on which they depend. Some indigenous groups manipulate the local landscape to augment its heterogeneity, and some have been found to be motivated to restore biodiversity in degraded landscapes. Their practices for the conservation of biodiversity were grounded in a series of rules of thumb which are apparently arrived at through a trial and error process over a long historical time period. This implies that their knowledge base is indefinite and their implementation involves an intimate relationship with the belief system. Such knowledge is difficult for western science to understand. It is vital, however, that the value of the knowledge-practice-belief complex of indigenous peoples relating to conservation of biodiversity is fully recognized if ecosystems and biodiversity are to be managed sustainably. Conserving this knowledge would be most appropriately accomplished through promoting the community-based resource-management systems of indigenous peoples.

Biodiversity Conservation as a Tool of Rural Development

An novel approach to critical biodiversity conservation in Ecuadorian tropical forests that includes local populations in design an implementation.

Fernández, Sarah Haidée. “The Value of Small-Scale Projects in Biodiversity Conservation and Sustainable Rural Development in the Ecuadorian Chocó.” (2013).
Abstract: The humid forests of the Chocó biogeographic region are characterized by high biodiversity and species endemism, as well as rapid habitat loss. This is especially the case of the Chocó forests within Ecuador. Since the second half of the twentieth century, the Ecuadorian Chocó has been reduced to less than 4% of its original forest cover, particularly as a consequence of logging, the expansion of African oil palm plantations and changing forms of land tenure since the late 1960s. Following a request from an international conservation NGO, fieldwork for this dissertation began with the aim to determine the route for a viable ecological corridor between the two largest Chocó fragments remaining in the country, the ecological reserves of Mache-Chindul and Cotacachi-Cayapas. In response to a series of incongruities observed between the NGO’s assumptions and realities on the ground, this dissertation employs a matrix ecology approach and challenges deeply-entrenched notions in traditional conservation by attempting to devise more effective strategies for biodiversity conservation and sustainable development that include local populations in design and implementation. It does so through the use of two case studies, Río Muchacho and Fundación Golondrinas, which are representative of a widespread emergence of local, small-scale conservation/rural development/ecotourism projects in the landscape matrix in the Ecuadorian Chocó (and rural Ecuador in general). A detailed qualitative assessment of these projects, their relationship with members of surrounding communities and their different approaches to achieving their stated conservation and development goals is complemented by remote sensing analysis of land cover changes over the last 12 years in these study sites. Based on the aforementioned qualitative and quantitative analyses undertaken in this dissertation, a few major factors are analyzed in terms of their potential for success: ecotourism, social capital in the form of local organizations with effective networks linking to outside markets, and the formulation of any program within an appropriate local spatial context. Applications of these findings are subsequently considered in wider-ranging strategies for the development of an ecological corridor between Mache-Chindul and Cotacachi-Cayapas.


Ecological Benefits

A Handbook of Ecological Restoration
Clewell, A., Aronson, J. and Winterhalder, K., 2004. The SER international primer on ecological restoration.
“Ecological restoration is an intentional activity that initiates or accelerates the recovery of an ecosystem with respect to its health, integrity and sustainability. Frequently, the ecosystem that requires restoration has been degraded, damaged, transformed or entirely destroy ed as the direct or indirect result of human activities. In some cases, these impacts to ecosystems have been caused or aggravated by natural agencies such as wildfire, floods, storms, or volcanic eruption, to the point at which the ecosystem cannot recover its predisturbance state or its historic developmental trajectory.”

Two Books by Thomas Lovejoy:

Lovejoy, T.E. and R.O. Bierregaard. 1990. Central Amazonian forests and the minimum critical size of ecosystems project. In Four neotropical rainforests, ed. A.H. Gentry, 60-71. New Haven: Yale University Press.
Lovejoy, T.E. and L. Hannah (eds). 2019. Biodiversity and Climate Change Transforming the Biosphere. New Haven:Yale University Press. 416pp.


Understanding Design Parameters in Sizing and Distance between “Islands” to be Effective

MacArthur, Robert H.; Edward O. Wilson The Theory of Island Biogeography. Princeton, N.J.: Princeton University Press. pp. 203 pp. ISBN 978-0-691-08836-5. (1967).
Abstract: Biogeography was stuck in a “natural history phase” dominated by the collection of data, the young Princeton biologists Robert H. MacArthur and Edward O. Wilson argued in 1967. In this book, the authors developed a general theory to explain the facts of island biogeography. The theory builds on the first principles of population ecology and genetics to explain how distance and area combine to regulate the balance between immigration and extinction in island populations. The authors then test the theory against data. The Theory of Island Biogeography was never intended as the last word on the subject. Instead, MacArthur and Wilson sought to stimulate new forms of theoretical and empirical studies, which will lead in turn to a stronger general theory. Even a third of a century since its publication, the book continues to serve that purpose well. From popular books like David Quammen’s Song of the Dodo to arguments in the professional literature, The Theory of Island Biogeography remains at the center of discussions about the geographic distribution of species. In a new preface, Edward O. Wilson reviews the origins and consequences of this classic book.

Biodiversity Hotspots

Conservation International 2014. Hotspots. Targeted investment in nature’s most important places. Retrieved 1 September, 2018, from
“There are places on Earth that are both biologically rich — and deeply threatened. For our own sake, we must work to protect them.”

Biodiversity and Functions in Forest and Grassland Ecosystems

Relationship of biodiversity – ecosystem functioning in forest and grassland ecosystems.

Diversity-dependent temporal divergence of ecosystem functioning in experimental ecosystems. / Guerrero-Ramirez, N. R. et. al, Nature Ecology & Evolution (2017)
Abstract: The effects of biodiversity on ecosystem functioning generally increase over time, but the underlying processes remain unclear. Using 26 long-term grassland and forest experimental ecosystems, we demonstrate that biodiversity–ecosystem functioning relationships strengthen mainly by greater increases in functioning in high-diversity communities in grasslands and forests. In grasslands, biodiversity effects also strengthen due to decreases in functioning in low-diversity communities. Contrasting trends across grasslands are associated with differences in soil characteristics


Biodiversity in Sustainable Forest Management

A methodological study to determine maximum diversity in selective cutting determines forests cut by uniform spacing can be ecologically sound in Guarani Reserve, Misiones, Argentina.

“Tree Regeneration and Species Diversity Following Conventional and Uniform Spacing Methods of Selective Cutting in a Subtropical Humid Forest Reserve.”Montagnini, Florencia, et al. Biotropica, vol. 30, no. 3, 1998, pp. 349–361. JSTOR, JSTOR,
Abstract: There are a variety of ways to diminish the negative impacts of forest management for timber on biodiversity. A pilot project using a uniform spacing method of selective cutting was recently implemented in the 5340 ha Guarani Reserve, Misiones, Argentina, to design adequate management schemes for the subtropical forests of the region. Uniform spacing involves moderate timber harvesting and careful selection of remnant trees. In this article we compare tree regeneration in forests experimentally cut by diameter limit and uniform spacing methods. Seedlings of five size classes from 10 cm to 3 m in height were sampled using rectangular nested plots. Three years after cutting, an average of 54,330 and 22,270 seedling/ha (all height classes combined) of commercial and non-commercial species were found in the forest cut by uniform spacing and by minimum diameter, respectively. In an adjacent uncut forest there were 34,900 seedlings/ha, and in another forest cut by minimum diameters 30 years ago there were 50,000 seedlings/ha, The forest cut by uniform spacing had the highest number of commercial seedlings/ha, with three times as many as the forest cut by minimum diameter three years ago and twice as many as the forest treated by minimum diameters 30 years ago. The forest cut by uniform spacing and the forest treated by minimum diameters 30 years ago had the highest diversity of understory plants other than trees, as well as heterogeneous canopy cover, while the other two forests had a predominance of bamboo in the understory and more open canopy conditions. Although lack of site replication limits interpretation of the results, these early findings suggest that the uniform spacing method can be an ecologically sound forest management option for the region.

Restoring Biodiversity of Degraded Landscapes

Understanding seed rain and seed dispersal agents in various plantation types and landscapes among various plant species.

Seed Rain and Seed Dispersal Agents in Pure and Mixed Plantations of Native Trees and Abandoned Pastures at La Selva Biological Station, Costa Rica.  Zamora, C. O. and Montagnini, F. (2007), Restoration Ecology, 15: 453–461. doi:10.1111/j.1526-100X.2007.00241.x
Abstract: Lack of seed dispersal can be an important obstacle to natural regeneration (NR) of degraded pastures in the humid tropics. Tree plantations can facilitate secondary forest succession by attracting seed dispersal agents from nearby forests. We studied seed rain and seed dispersal agents in 12–13 years old pure and mixed native tree plantations at La Selva Biological Station, Costa Rica from July to December 2004. Plantations of Balizia elegans (5,522), Dipteryx panamensis (2,263), and Jacaranda copaia (2,091) had the greatest total seed abundance; treatments with the least total seed abundance were Calophyllum brasiliense (56), nonplanted abandoned pasture control 2 (353), Mixed Species 2 (389), and control 1 (836). Plantations of J. copaia and Hyeronima alchorneoides had the greatest seed species richness density, whereas the lowest seed species richness was found in the control treatments. The NR plots had more seeds dispersed by wind, whereas in the plantations, the most important dispersal agents were birds and mammals. The most abundant seeds were those of Miconia spp. (14,492),Psychotria bracheata (2,252), and the Poaceae family (1,346), all species from early successional stages. Plantations of native species are effective in attracting seed dispersal agents and thus facilitating regeneration of degraded pasturelands in the region.


Agroforestry & Agricultural

Traditional agriculture in Mesoamerican Homegardens and the contribution to biodiversity in addition to carbon sequestration, nutrient cycling, and other co-benefits.

Homegardens of Mesoamerica: Biodiversity, Food Security, and Nutrient Management / F. Montagnini
Abstract. The region of Mesoamerica is densely populated and it suffers from poverty and malnutrition both in urban and rural areas. It is home to the Mayan civilization that practiced sustainable agricultural systems, involving many native crops and soil conservation strategies, for centuries. The homegardens, which provide the household with a basic food source as well as high value products to generate cash income are important in Mesoamerica, and are often used as tools in development projects that promote food security, especially in the poorest areas of Mesoamerica. The Mesoamerican homegardens are quite diverse in vertical and horizontal structure and species composition. Both exotic and native plants are used, with emphasis on fruit trees. Domestic animals, especially chickens and pigs, add protein to a diet that is generally protein-deficient. Many indigenous communities (descendants of the ancient
Maya) still manage these homegardens using techniques that include residue management and ash deposition, thus enhancing nutrient recycling and conservation. Carbon sequestration may be important due to the efficient capture of solar radiation in the multi-layered homegardens, although its global or regional importance is minimal due to the relatively small area under the homegarden system. Management strategies that promote nutrient recycling and maintain high species diversity should be encouraged to ensure sustainability of homegardens in the region.

Integration of agriculture and biodiversity conservation-

Harvey, C.A., O. Komar, R. Chazdon, B.G. Ferguson, B. Finegan, D.M. Griffith, M. Martínez‐Ramos, H. Morales, R. Nigh, L. Soto‐Pinto, M. Van Breugel, and M. Wishnie. 2008. Integrating agricultural landscapes with biodiversity conservation in the Mesoamerican hotspot. Conservation Biology 22(1): 8-15.
Intro Paragraph: The major challenge in tropical land management is to meet the ever‐growing demand for agricultural products while conserving biodiversity, providing critical ecosystem services, and maintaining rural livelihoods. This challenge is particularly acute in the Mesoamerican biodiversity hotspot, a region of high conservation value for both wild and domesticated species that is undergoing rapid human population growth, ecological degradation, and loss of traditional farming systems (Myers et al. 2000; Harvey et al. 2005a). Approximately 80% of the region’s vegetation has been converted to agriculture, threatening biodiversity. More than 300 of the region’s endemic species of flora and fauna are threatened, including at least 107 that are critically endangered (CI 2007). With continuing habitat loss (deforestation is 1.2%/year in Central America and Mexico combined; FAO 2005) and fragmentation of remaining forests, pressure on the region’s biodiversity will intensify.


Agroforestry as an important harbor of biodiversity conservation in human dominated landscapes.

Bhagwat, S.A., Willis, K.J., Birks, H.J.B. and Whittaker, R.J., 2008. Agroforestry: a refuge for tropical biodiversity?. Trends in ecology & evolution, 23(5), pp.261-267.
Abstract: As rates of deforestation continue to rise in many parts of the tropics, the international conservation community is faced with the challenge of finding approaches which can reduce deforestation and provide rural livelihoods in addition to conserving biodiversity. Much of modern-day conservation is motivated by a desire to conserve ‘pristine nature’ in protected areas, while there is growing recognition of the long-term human involvement in forest dynamics and of the importance of conservation outside protected areas. Agroforestry – intentional management of shade trees with agricultural crops – has the potential for providing habitats outside formally protected land, connecting nature reserves and alleviating resource-use pressure on conservation areas. Here we examine the role of agroforestry systems in maintaining species diversity and conclude that these systems can play an important role in biodiversity conservation in human-dominated landscapes.

The utility of  habitat patches as a harbor for biodiversity. In this study, of particular interest is habitat patches and species diversity in cork oak agroforestry systems.

Rosalino, L.M., do Rosario, J. and Santos-Reis, M., 2009. The role of habitat patches on mammalian diversity in cork oak agroforestry systems. Acta Oecologica, 35(4), pp.507-512.
Abstract: Habitat patches, depending on the degree of differentiation from the matrix, can add few or many elements to the species pool of a particular landscape. Their importance to biodiversity is particularly relevant in areas with complex landscapes, where natural, naturalized, or managed habitats are interspersed by small patches of habitat types with very different biophysical characteristics; e.g., fruit orchards and riparian areas. This is the case of the montado landscape, a cork oak agroforestry system that largely covers south-western Portugal. We evaluated whether the high mammalian biodiversity found in this system is, in part, the cumulative result of the species found in the non-matrix habitats. Our results indicate that in areas where there are inclusions of orchards/olive yards and riparian vegetation in the cork oak woodland, a significantly higher number of mammalian species are present. We further detected a positive effect of low human disturbance on mammal diversity. Ultimately, our results can be used by managers to augment their management options, since we show that the inclusion and maintenance of non-matrix habitat patches in cork oak agro-silvo-forestry systems can help to maximize mammal biodiversity without compromising services associated with agriculture and forestry.

Land Sharing vs Land Sparing…

Phalan, B., M. Onial, A. Balmford, and R.E. Green, 2011. Reconciling food production and biodiversity conservation: land sharing and land sparing compared. Science 333(6047): 1289-1291
Abstract: The question of how to meet rising food demand at the least cost to biodiversity requires the evaluation of two contrasting alternatives: land sharing, which integrates both objectives on the same land; and land sparing, in which high-yield farming is combined with protecting natural habitats from conversion to agriculture. To test these alternatives, we compared crop yields and densities of bird and tree species across gradients of agricultural intensity in southwest Ghana and northern India. More species were negatively affected by agriculture than benefited from it, particularly among species with small global ranges. For both taxa in both countries, land sparing is a more promising strategy for minimizing negative impacts of food production, at both current and anticipated future levels of production.

Agroforestry as a tool for species diversity in mixed coffee plantations and the value of agricultural landscape design as a tool for sustainable and resilient biodiversity services.

Valencia, V., García-Barrios, L., West, P., Sterling, E.J. and Naeem, S., 2014. The role of coffee agroforestry in the conservation of tree diversity and community composition of native forests in a Biosphere Reserve. Agriculture, ecosystems & environment, 189, pp.154-163.
Abstract: Sustainable and resilient agricultural systems are needed to feed and fuel a growing human population. However, the current model of agricultural intensification which produces high yields has also resulted in a loss of biodiversity, ecological function, and critical ecosystem services in agricultural landscapes. A key consequence of agricultural intensification is landscape simplification, where once heterogeneous landscapes contain increasingly fewer crop and non-crop habitats. Landscape simplification exacerbates biodiversity losses which leads to reductions in ecosystem services on which agriculture depends. In recent decades, considerable research has focused on mitigating these negative impacts, primarily via management of habitats to promote biodiversity and enhance services at the local scale. While it is well known that local and landscape factors interact, modifying overall landscape structure is seldom considered due to logistical constraints. I propose that the loss of ecosystem services due to landscape simplification can only be addressed by a concerted effort to fundamentally redesign agricultural landscapes. Designing agricultural landscapes will require that scientists work with stakeholders to determine the mix of desired ecosystem services, evaluate current landscape structure in light of those goals, and implement targeted modifications to achieve them. I evaluate the current status of landscape design, ranging from fundamental ecological principles to resulting guidelines and socioeconomic tools. While research gaps remain, the time is right for ecologists to engage with other disciplines, stakeholders, and policymakers in education and advocacy to foster agricultural landscape design for sustainable and resilient biodiversity services.


Biodiversity in Biological Corridors Through Human Modified Landscapes

Homegardens as a positive contribution to species biodiversity.

Redondo Brenes and Montagnini 2010 – Contribution of Homegardens Agrosilvopaturals Systems, and Other Human Dominated Land Use Types to the Avian Diversity of a Biological Corridor in Costa Rica.
Abstract: As a result of the limitations of protected areas in providing habitat for many wildlife species, in the last two decades efforts have shifted to studying wildlife conservation in human-dominated landscapes. The present study was carried out in the Path of the Tapir Biological Corridor, Costa Rica. The corridor, an 82,00 ha area of fragmented forests, encompasses 55 rural communities with more than 10,000 people. Deforestation and development are the main threats to biodiversity in the region. The main objective of this study was to estimate the contribution of ten habitat types: forested areas (wildlife refuges and biological reserves), agroforestry systems (home gardens and agrosilvopastoral systems), and other human-dominated land uses on the conservation of bird species in the corridor. Bird data was obtained using point counts along a whole year. Each habitat type had a total of 20 sampling points (200 points total), and each sampling point was listed three times during the summer and three times during the winter seasons. The bird species were categorized by habitat preference, habitat and feeding guilds, and endangered status. We identified a total of 21,015 bird individuals that corresponded to 293 species. Forest fallows (155 species), forest edges (154), home gardens (148), and agrosilvopastoral systems (143) were the land uses with the most species. On the other hand villages (104 species), oil palm plantations (107), residential tourism projects (111), and tree plantations (115) had the lowest bird species richness values. Biological reserves (124 species) and wildlife refuges (121) had intermediate species richness values. But, they both provided habitat to 68 forest dependent species that were not found in any other habitat type, and to 19 species (70%) of the species of conservation concern, thus they are a priority habitat for conservation in the region. It is also relevant to highlight the importance of home gardens and agrosilvopastoral systems as habitat for 70% of the avian diversity of the region, including the endangered Scarlet Macaw (are Macao). Biodiversity conservation should always include primary and old-secondary forests (e.g., those forests located in wildlife refuges, biological reserves, or isolated forest fragments) as these are the most important habitat type for wildlife at the landscape level. However, the results of this research also show that the matrix, especially agroforestry systems and tree plantations, are important to ensure wildlife conservation in the biological corridor in the resort and long term.


The role and value of remnant forests through agro-ecosystems and human dominated landscapes as a harbor for biodiversity.

Anand, M.O., Krishnaswamy, J., Kumar, A. and Bali, A., 2010. Sustaining biodiversity conservation in human-modified landscapes in the Western Ghats: remnant forests matter. Biological Conservation, 143(10), pp.2363-2374.
Abstract: Human-modified tropical landscapes under semi-natural or agro-ecosystems often harbor biodiversity of significant conservation value. In the Western Ghats of India, these ecosystems also provide connectivity between protected areas and other remnant forests. We investigated the conservation value of these landscapes and agro-ecosystems using results from 35 studies covering 14 taxonomic groups. Large, conspicuous taxonomic groups and tree-covered land-use types have received much focus in this area of research in the Western Ghats. We computed a response ratio defined as the log ratio of species richness in human land use to species richness in forest control site from 17 studies. In a meta-analysis, we investigated variation of this ratio across studies with respect to three variables: taxonomic group, the land-use type sampled and the extent of forest cover within the study landscape. Higher forest cover within the landscape emerged as a major positive influence on biodiversity in human-modified landscapes for vertebrates and vegetation while no patterns emerged for invertebrates. Our results suggest that loss of remnant forest patches from these landscapes is likely to reduce biodiversity within agro-ecosystems and exacerbate overall biodiversity loss across the Western Ghats. Conservation of these remnant forest patches through protection and restoration of habitat and connectivity to larger forest patches needs to be prioritized. In the densely populated Western Ghats, this can only be achieved by building partnerships with local land owners and stakeholders through innovative land-use policy and incentive schemes for conservation.

Home Gardens as harbors of biodiversity-

Galluzzi, G., P. Eyzaguirre, and V. Negri. 2010. Home gardens: neglected hotspots of agro-biodiversity and cultural diversity. Biodiversity and Conservation 19(13): 3635-3654.
Abstract: Over the last two decades, the importance of conserving genetic resources has received increasing attention. In this context the role of home gardens as repositories of biological diversity has been acknowledged but still a comprehensive, interdisciplinary investigation of their agro-biodiversity is lacking. Home gardens, whether found in rural or urban areas, are characterized by a structural complexity and multifunctionality which enables the provision of different benefits to ecosystems and people. Studies carried out in various countries demonstrate that high levels of inter- and intra-specific plant genetic diversity, especially in terms of traditional crop varieties and landraces, are preserved in home gardens. Families engage in food production for subsistence or small-scale marketing and the variety of crops and wild plants provides nutritional benefits. At the same time, home gardens are important social and cultural spaces where knowledge related to agricultural practices is transmitted and through which households may improve their income and livelihoods. The present article summarizes available literature on the biological and cultural significance of agro-biodiversity in home gardens. It discusses future constraints and opportunities in home garden research, in the prospect of defining and promoting their role in conservation of agricultural biodiversity and cultural heritage. KeywordsHome gardens-Agro-ecosystems-In situ conservation-Agro-biodiversity-Landraces

Agricultural landscapes management and design for biodiversity, in particular coffee agro-ecosystems.

Landis, D.A., 2017. Designing agricultural landscapes for biodiversity-based ecosystem services. Basic and Applied Ecology18, pp.1-12.
Abstract: Agroforestry is considered a promising alternative to conventional agriculture that can both conserve biodiversity and support local livelihoods. Coffee agroforestry may be particularly important for sustaining trees of conservation concern and late-successional stage, but this possibility remains unclear. Here, we examined whether coffee agroforestry systems can serve as conservation reservoirs of tree species native to nearby forests. We compared tree diversity, composition and structure between coffee agroforests and forests in La Sepultura Biosphere Reserve in Chiapas, Mexico. We found that, although at the landscape level the full set of coffee agroforests appears to conserve comparable tree species richness to nearby native forests, the species composition that is being conserved is different. Coffee agroforests had a lower proportion of trees of conservation concern, a higher proportion of pioneer trees, were dominated by Inga spp., harbored lower tree species diversity at the plot level, and were composed of different tree species compared to native forests. We suggest that conservation practitioners and policy makers seeking to promote coffee agroforestry as a conservation strategy should consider how such agroforestry systems differ in species diversity and composition from the native forests of conservation interest. Further, promoting different coffee agroforest management strategies, such as discouraging the replacement of diverse agroforest canopies with Inga-dominated canopies, would help improve the conservation value of coffee agroforests through more sustainable practices.

Integrated Landscape Management as a tool for development and reaching Sustainable Development Goals-

Thaxton, M., Forster, T., Hazlewood, P., Mercado, L., Neely, C., Scherr, S.J., Wertz, L., Wood, S. and Zandri, E., 2016. Landscape partnerships for sustainable development: achieving the SDGs through integrated landscape management. White Paper Produced By The Landscapes for People, Food, and Nature Initiative’s Task Force On the Sustainable Development Goals. .28pp   The Landscapes for People, Food and Nature Initiative is a global network of more than 70 conservation, development, and agriculture organizations who champion integrated landscape management at landscape, national and international levels. Founded in 2011, the Initiative is co-organized by Bioversity International, EcoAgriculture Partners, the Food and Agriculture Organization of the United Nations (FAO), Ministry of Economic Affairs of the Government of the Netherlands, the United Nations Environment Programme (UNEP), World Agroforestry Centre (ICRAF), World Bank, and World Resources Institute. The Initiative links and adds value to the many landscape initiatives and networks already in place worldwide, and coordinates action to improve the enabling environment for integrated landscape management. To learn more, visit us at

Design Strategies

The role of Human Modified Landscapes in Biodiversity Conservation- How to understand and frame disturbances and land use interactions with tropical biodiversity and ecosystem services.

Melo, F.P., Arroyo-Rodríguez, V., Fahrig, L., Martínez-Ramos, M. and Tabarelli, M., 2013. On the hope for biodiversity-friendly tropical landscapes. Trends in ecology & evolution, 28(8), pp.462-468.
With the decreasing affordability of protecting large blocks of pristine tropical forests, ecologists have staked their hopes on the management of human-modified landscapes (HMLs) to conserve tropical biodiversity. Here, we examine key forces affecting the dynamics of HMLs, and propose a framework connecting human disturbances, land use, and prospects for both tropical biodiversity and ecosystem services. We question the forest transition as a worldwide source of new secondary forest; the role played by regenerating (secondary) forest for biodiversity conservation, and the resilience of HMLs. We then offer a conceptual model describing potential successional trajectories among four major landscape types (natural, conservation, functional, and degraded) and highlight the potential implications of our model in terms of research agendas and conservation planning.

Correlations between reserve size and biodiversity-

Diamond, J.M., 1975. The island dilemma: lessons of modern biogeographic studies for the design of natural reserves. Biological conservation, 7(2), pp.129-146.
Abstract: A system of natural reserves, each surrounded by altered habitat, resembles a system of islands from the point of view of species restricted to natural habitats. Recent advances in island biogeography may provide a detailed basis for understanding what to expect of such a system of reserves. The main conclusions are as follows: The number of species that a reserve can hold at equilibrium is a function of its area and its isolation. Larger reserves, and reserves located close to other reserves, can hold more species. If most of the area of a habitat is destroyed, and a fraction of the area is saved as a reserve, the reserve will initially contain more species than it can hold at equilibrium. The excess will gradually go extinct. The smaller the reserve, the higher will be the extinction rates. Estimates of these extinction rates for bird and mammal species have recently become available in a few cases.Different species require different minimum areas to have a reasonable chance of survival. Some geometric design principles are suggested in order to optimise the function of reserves in saving species. The role of reserves and dynamic ecosystem strategies for optimal species success.

Synthesis of literature of SLOSS Model for natural reserves. Reserve size in relation to biodiversity.

Tjørve, E., 2010. How to resolve the SLOSS debate: Lessons from species-diversity models. Journal of Theoretical Biology, 264(2), pp.604-612.
Abstract: The SLOSS debate – whether a single large reserve will conserve more species than several small – of the 1970s and 1980s never came to a resolution. The first rule of reserve design states that one large reserve will conserve the most species, a rule which has been heavily contested. Empirical data seem to undermine the reliance on general rules, indicating that the best strategy varies from case to case. Modeling has also been deployed in this debate. We may divide the modeling approaches to the SLOSS enigma into dynamic and static approaches. Dynamic approaches, covered by the fields of island equilibrium theory of island biogeography and metapopulation theory, look at immigration, emigration, and extinction. Static approaches, such as the one in this paper, illustrate how several factors affect the number of reserves that will save the most species.                           This article approaches the effect of different factors by the application of species-diversity models. These models combine species–area curves for two or more reserves, correcting for the species overlap between them. Such models generate several predictions on how different factors affect the optimal number of reserves. The main predictions are: Fewer and larger reserves are favored by increased species overlap between reserves, by faster growth in number of species with reserve area increase, by higher minimum-area requirements, by spatial aggregation and by uneven species abundances. The effect of increased distance between smaller reserves depends on the two counteracting factors: decreased species density caused by isolation (which enhances minimum-area effect) and decreased overlap between isolates. The first decreases the optimal number of reserves; the second increases the optimal number. The effect of total reserve-system area depends both on the shape of the species–area curve and on whether overlap between reserves changes with scale.                                 The approach to modeling presented here has several implications for conservational strategies. It illustrates well how the SLOSS enigma can be reduced to a question of the shape of the species–area curve that is expected or generated from reserves of different sizes and a question of overlap between isolates (or reserves).

Effects of habitat fragmentation on biodiversity

Fahrig, L., 2003. Effects of habitat fragmentation on biodiversity. Annual review of ecology, evolution, and systematics, 34(1), pp.487-515.
AbstractThe literature on effects of habitat fragmentation on biodiversity is huge. It is also very diverse, with different authors measuring fragmentation in different ways and, as a consequence, drawing different conclusions regarding both the magnitude and direction of its effects. Habitat fragmentation is usually defined as a landscape-scale process involving both habitat loss and the breaking apart of habitat. Results of empirical studies of habitat fragmentation are often difficult to interpret because (a) many researchers measure fragmentation at the patch scale, not the landscape scale and (b) most researchers measure fragmentation in ways that do not distinguish between habitat loss and habitat fragmentation per se, i.e., the breaking apart of habitat after controlling for habitat loss. Empirical studies to date suggest that habitat loss has large, consistently negative effects on biodiversity. Habitat fragmentation per se has much weaker effects on biodiversity that are at least as likely to be positive as negative. Therefore, to correctly interpret the influence of habitat fragmentation on biodiversity, the effects of these two components of fragmentation must be measured independently. More studies of the independent effects of habitat loss and fragmentation per se are needed to determine the factors that lead to positive versus negative effects of fragmentation per se. I suggest that the term “fragmentation” should be reserved for the breaking apart of habitat, independent of habitat loss.

The overall reserve area within a patch matrix within a defined landscape is the determinate factor of biodiversity rather than individual patch size or position.

Fahrig, L., 2013. Rethinking patch size and isolation effects: the habitat amount hypothesis. Journal of Biogeography, 40(9), pp.1649-1663.
Abstract I challenge (1) the assumption that habitat patches are natural units of measurement for species richness, and (2) the assumption of distinct effects of habitat patch size and isolation on species richness. I propose a simpler view of the relationship between habitat distribution and species richness, the ‘habitat amount hypothesis’, and I suggest ways of testing it. The habitat amount hypothesis posits that, for habitat patches in a matrix of non-habitat, the patch size effect and the patch isolation effect are driven mainly by a single underlying process, the sample area effect. The hypothesis predicts that species richness in equal-sized sample sites should increase with the total amount of habitat in the ‘local landscape’ of the sample site, where the local landscape is the area within an appropriate distance of the sample site. It also predicts that species richness in a sample site is independent of the area of the particular patch in which the sample site is located (its ‘local patch’), except insofar as the area of that patch contributes to the amount of habitat in the local landscape of the sample site. The habitat amount hypothesis replaces two predictor variables, patch size and isolation, with a single predictor variable, habitat amount, when species richness is analysed for equal-sized sample sites rather than for unequal-sized habitat patches. Studies to test the hypothesis should ensure that ‘habitat’ is correctly defined, and the spatial extent of the local landscape is appropriate, for the species group under consideration. If supported, the habitat amount hypothesis would mean that to predict the relationship between habitat distribution and species richness: (1) distinguishing between patch-scale and landscape-scale habitat effects is unnecessary; (2) distinguishing between patch size effects and patch isolation effects is unnecessary; (3) considering habitat configuration independent of habitat amount is unnecessary; and (4) delineating discrete habitat patches is unnecessary.
Bengtsson, J., Angelstam, P., Elmqvist, T., Emanuelsson, U., Folke, C., Ihse, M., Moberg, F. and Nyström, M., 2003. Reserves, resilience and dynamic landscapes. AMBIO: A Journal of the Human Environment, 32(6), pp.389-396.
Abstract: In a world increasingly modified by human activities, the conservation of biodiversity is essential as insurance to maintain resilient ecosystems and ensure a sustainable flow of ecosystem goods and services to society. However, existing reserves and national parks are unlikely to incorporate the long-term and large-scale dynamics of ecosystems. Hence, conservation strategies have to actively incorporate the large areas of land that are managed for human use. For ecosystems to reorganize after large-scale natural and human-induced disturbances, spatial resilience in the form of ecological memory is a prerequisite. The ecological memory is composed of the species, interactions and structures that make ecosystem reorganization possible, and its components may be found within disturbed patches as well in the surrounding land-scape. Present static reserves should be complemented with dynamic reserves, such as ecological fallows and dynamic successional reserves, that are part of ecosystem management mimicking natural disturbance regimes at the landscape level.

Modern Industrial Agriculture as a decreasing force in global biodiversity and agri-environmental schemes to reverse these impacts.

Berendse, F., Chamberlain, D., Kleijn, D. and Schekkerman, H., 2004. Declining biodiversity in agricultural landscapes and the effectiveness of agri-environment schemes. Ambio: A journal of the Human environment, 33(8), pp.499-502.
Abstract Agricultural intensification, greatly accelerated as a result of the EU Common Agricultural Policy (CAP), has led to rastic reductions in the populations of many wild plant and animal species that used to be characteristic of farmland. In 1992, the EU provided the member states with its Agri-environment Regulation 2078/92 to help member states reverse these developments by means of agri-environment schemes. The question is: will the implementation of these schemes be sufficient to restore the biological diversity on farmland? Most studies that have examined the effectiveness of agri-environment schemes have focused on farmland birds in Great Britain and The Netherlands. So far, the positive effects appear to be limited. Continuous evaluation and adaptation of these schemes is needed to enable the biodiversity on farmland to recover from the EU’s former policy.

Lessons, approaches, and practices for biodiversity conservation in Asia. Understanding the political and economic forces and how to navigate for best practices.

Sayer, J., Chokkalingam, U. and Poulsen, J., 2004. The restoration of forest biodiversity and ecological values. Forest ecology and management, 201(1), pp.3-11.
Abstract: Large investments are being made in the establishment of tree plantations on degraded land in Asia. These initiatives are often politically driven and aspire to achieve both economic and environmental benefits. However, the lack of clarity about the precise objectives of these schemes means that they often fail to yield either local economic or global environmental benefits. There is often a failure to negotiate with all concerned stakeholders and to recognize and resolve trade-offs. Subsidies have often had perverse impacts, and market forces may be better drivers of economic objectives of restoration programmes. Security of tenure and use rights is an important but often neglected requirement for achieving sustainability. Remnant patches of natural vegetation, even when degraded, are often valuable sources of local biodiversity in restoration schemes. The spatial patterns of different types of forest and of non-forest land are important determinants of environmental values. Biodiversity conservation requires maintaining or re-establishing habitat strips to connect natural forest blocks and protect ecological gradients. However, even monoculture plantations often have significant biodiversity value. The fundamental principles of ecosystem approaches as adopted by the Convention for the Conservation of Biological Diversity and principles for successful common property resource management provide valuable frameworks for forest restoration schemes.

Increasing forest cover is imperative for maintaining biodiversity in a fragmented landscape.

Boesing, A.L., Nichols, E. and Metzger, J.P., 2017. Biodiversity extinction thresholds are modulated by matrix type. Ecography.
Biodiversity extinction thresholds are abrupt declines in biological diversity that occur with habitat loss, associated with a decline in habitat connectivity. Matrix quality should influence the location of thresholds along habitat loss gradients through its effects on connectivity; however these relationships have seldom been explored empirically. Using field data from 23 independent 1254 ha landscapes in the Brazilian Atlantic Forest, we evaluated how tropical avian biodiversity responds to native forest loss within habitat patches embedded either in homogeneous pasture matrix context (with a high proportion of cattle pastures), and heterogeneous coffee matrix context (with high abundance of sun coffee plantations). We considered taxonomic, functional, and phylogenetic diversity, and tested if matrix type and choice of diversity metric influenced the location of biodiversity thresholds along the forest cover gradient. We found that matrix type postponed the abrupt loss of taxonomic diversity, from a threshold of 35% of forest cover in homogeneous pasture matrix to 19% in heterogeneous coffee matrix. Phylogenetic diversity responded similarly, with thresholds at 30 and 24% in homogeneous-pasture and heterogeneous-coffee matrices, respectively, but no relationship with forest cover was detected when corrected for richness correlation. Despite the absence of a threshold for functional diversity in either matrix types, a strong decline below 20% of habitat amount was detected. Finally, below 20% native habitat loss, all diversity indices demonstrated abrupt declines, indicating that even higher-quality matrices cannot postpone diversity loss below this critical threshold. These results highlight that taxonomic diversity is a more sensitive index of biodiversity loss in fragmented landscapes, which may be used as a benchmark to prevent subsequent functional and phylogenetic losses. Furthermore, increasing matrix quality appears an efficient conservation strategy to maintain higher biodiversity levels in fragmented landscapes over a larger range of habitat loss.

Land Sparing vs. Land Sharing

Crespin, S. J., Simonetti, J. A. 2019. Reconciling farming and wild nature: Integrating human–wildlife coexistence into the land-sharing and land-sparing framework. Ambio 48:131–138
Land has traditionally been spared to protect biodiversity; however, this approach has not succeeded by itself and requires a complementary strategy in human-dominated landscapes: land-sharing. Human–wildlife conflicts are rampant in a land-sharing context where wildlife co-occur with crops or livestock, but whose resulting interactions adversely affect the wellbeing of land owners, ultimately impeding coexistence. Therefore, true land-sharing only works if coexistence is also considered an end goal. We reviewed the literature on land-sharing and found that conflicts have not yet found their way into the land-sharing/sparing framework, with wildlife and humans co-occurring without coexisting in a dynamic process. To successfully implement a land-sharing approach, we must first acknowledge our failure to integrate the body of work on human–wildlife conflicts into the framework and work to implement multidisciplinary approaches from the ecological, economic, and sociological sciences to overcome and prevent conflicts. We suggest the use of Conflict Transformation by means of the Levels of Conflict Model to perceive both visible and deep-rooted causes of conflicts as opportunities to create problem-solving dynamics in affected socio-ecological landscapes. Reconciling farming and nature is possible by aiming for a transition to landscapes that truly share space by virtue of coexistence.

Factors of consideration within the understandings of species diversity throughout the matrix of landscape fragmentation include factors of community composition in reserves, edge effects, the modified vegetation surrounding reserves within the matrix of fragmentation, and anthropogenic disturbances within reserves.

Laurance, W.F., 2008. Theory meets reality: how habitat fragmentation research has transcended island biogeographic theory. Biological conservation, 141(7), pp.1731-1744.
Abstract: Island biogeography theory (IBT) provides a basic conceptual model for understanding habitat fragmentation. Empirical studies of fragmented landscapes often reveal strong effects of fragment area and isolation on species richness, although other predictions of the theory, such as accelerated species turnover in fragments, have been tested less frequently. As predicted by IBT, biota in fragments typically ‘relax’ over time towards lower species richness. Beyond these broad generalizations, however, the relevance of IBT for understanding fragmented ecosystems is limited. First, IBT provides few predictions about how community composition in fragments should change over time, and which species should be most vulnerable. Second, edge effects can be an important driver of local species extinctions and ecosystem change, but are not considered by IBT. Third, the matrix of modified vegetation surrounding fragments—also ignored by IBT—can strongly influence fragment connectivity, which in turn affects the demography, genetics, and survival of local populations. Fourth, most fragmented landscapes are also altered by other anthropogenic changes, such as hunting, logging, fires, and pollution, which can interact synergistically with habitat fragmentation. Finally, fragmentation often has diverse impacts on ecosystem properties such as canopy-gap dynamics, carbon storage, and the trophic structure of communities that are not considered by IBT. I highlight these phenomena with findings from fragmented ecosystems around the world.

The longest running study of habitat fragmentation in the Amazon forest–

Laurance, W.F., J.L. Camargo, P.M. Fearnside, T.E. Lovejoy, G.B. Williamson, R.C. Mesquita, C.F. Meyer, P.E. Bobrowiec, and S.G. Laurance. 2018. An Amazonian rainforest and its fragments as a laboratory of global change. Biological Reviews 93(1): 223-247.
We synthesize findings from the world’s largest and longest-running experimental study of habitat fragmentation, in central Amazonia. Over the past 36 years, 11 forest fragments ranging from 1 ha to 100 ha in size have experienced a wide array of ecological changes. Edge effects have been a dominant driver of fragment dynamics, strongly affecting forest microclimate, tree mortality, carbon storage and fauna. The matrix of vegetation surrounding fragments has changed markedly over time (evolving from large cattle pastures to mosaics of abandoned pasture and secondary regrowth forest), and this, in turn, has strongly influenced the dynamics of fragments and faunal communities. Both rare weather events and apparent global-change drivers have significantly influenced forest structure and dynamics across the entire study area, both in forest fragments and in nearby intact forest. Such large-scale drivers are likely to interact synergistically with habitat fragmentation.

Open areas (e.g. pastures, annual crops) decrease landscape connectivity and resource availability for forest species

Dunning, J.B., Danielson, B.J. and Pulliam, H.R., 1992. Ecological processes that affect populations in complex landscapes. Oikos, pp.169-175.
Abstract: We describe a general framework for understanding the ecological processes that operate at landscape scales. The composition of habitat types in a landscape and the physiognomic or spatial arrangement of those habitats are the two essential features that are required to describe any landscape. As such, these two features affect four basic ecological processes that can influence population dynamics or community structure. The first two of these processes, landscape complementation and landscape supplementation, occur when individuals move between patches in the landscape to make use of non-substitutable and substitutable resources, respectively. The third process, source-sink dynamics, describes the consequences of having different individuals in the same population occupy habitat patches of different qualities. The fourth process, the neighborhood effect, describes how landscape effects can be amplified when the critical resources are in the landscape immediately surrounding a given patch. Definition of these landscape features and general processes will allow a better synthesis of how landscape variation affects populations and communities.

The edge effect within the matrix will determine a set of environmental conditions favorable for different species

Abstract: Habitat fragmentation changes thermal conditions in remnant patches, and thermal conditions strongly influence organism morphology, distribution, and activity patterns. However, few studies explore temperature as a mechanism driving ecological responses to fragmentation. Here we offer a conceptual framework that integrates thermal biology into fragmentation research to better understand individual, species, community, and ecosystem-level responses to fragmentation. Specifically, the framework addresses how fragmentation changes temperature and how the effects of those temperature changes spread through the ecosystem, from organism response via thermal sensitivity, to changes in species distribution and activity patterns, to shifts in community structure following species’ responses, and ultimately to changes in ecosystem functions. We place a strong emphasis on future research directions by outlining “Critical gaps” for each step of the framework. Empirical efforts to apply and test this framework promise new understanding of fragmentation’s ecological consequences and new strategies for conservation in an increasingly fragmented and warmer world.

Fragmentation in some instances may increase species diversity throughout the landscape.

Abstract: For this article, I reviewed empirical studies finding significant ecological responses to habitat fragmentation per se—in other words, significant responses to fragmentation independent of the effects of habitat amount (hereafter referred to as habitat fragmentation). I asked these two questions: Are most significant responses to habitat fragmentation negative or positive? And do particular attributes of species or landscapes lead to a predominance of negative or positive significant responses? I found 118 studies reporting 381 significant responses to habitat fragmentation independent of habitat amount. Of these responses, 76% were positive. Most significant fragmentation effects were positive, irrespective of how the authors controlled for habitat amount, the measure of fragmentation, the taxonomic group, the type of response variable, or the degree of specialization or conservation status of the species or species group. No support was found for predictions that most significant responses to fragmentation should be negative in the tropics, for species with larger movement ranges, or when habitat amount is low; most significant fragmentation effects were positive in all of these cases. Thus, although 24% of significant responses to habitat fragmentation were negative, I found no conditions in which most responses were negative. Authors suggest a wide range of possible explanations for significant positive responses to habitat fragmentation: increased functional connectivity, habitat diversity, positive edge effects, stability of predator–prey/host–parasitoid systems, reduced competition, spreading of risk, and landscape complementation. A consistent preponderance of positive significant responses to fragmentation implies that there is no justification for assigning lower conservation value to a small patch than to an equivalent area within a large patch—instead, it implies just the opposite. This finding also suggests that land sharing will usually provide higher ecological value than land sparing.

Patch Dynamics and Reserve Design.

Pickett, S.T. and J.N. Thompson. 1978. Patch dynamics and the design of nature reserves. Biological Conservation 13(1): 27-37.
Abstract: Island biogeographic theory has been applied to the design of nature reserves. However, immigration, which is important in maintaining species equilibrium on true islands, will not contribute significantly to the maintenance of equilibrium on reserves in the future because of the disappearance of recolonisation sources. Consequently, extinction becomes the dominant population process, and the internal disturbance dynamics become the critical design feature of reserves. The design of reserves should be based on ‘minimum dynamic area’, the smallest area with a natural disturbance regime which maintains internal recolonisation sources and hence minimises extinctions. Determination of minimum dynamic area must be based on knowledge of disturbance-generated patch size, frequency, and longevity, and the mobilities of the preserved species. These features have not all been explicitly considered in the previous island biogeographic design recommendations.

Refuge design and Island Biogeography.

Simberloff, D. and L.G. Abele. 1982. Refuge design and island biogeographic theory: effects of fragmentation. The American Naturalist 120(1): 41-50.
Abstract: Cole’s theoretical conclusion that one large site generally contains more species than several small ones of equal total area is falsified by data in the literature, as is his contention that exceptions will only occur when the species in the sites are but a small fraction of those in the species pool. For a variety of taxa, for a number of different habitat types, and for a wide range of sizes of the biota as a fraction of the pool, either there is no clear best strategy, or several small sites are better than one large site. Since there are numerous idiosyncratic biological considerations, plus a number of nonbiological ones that bear heavily on refuge design, it is unlikely that a general reductionist model can generate useful predictions or advice on this matter.