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Fragmentation creates heterogeneous landscapes with different interactions and trajectories. In this scenario, the understanding in how forest fragment sizes influence forest species patterns can lead the way for biodiversity management and conservation in agricultural landscapes. The aim of this study was to compare the density and the diameter distribution of Bertholletia excelsa, Carapa guianensis and Cedrelinga cateniformis among fragments of different sizes, located at the Agro-Extractivist Settlement Project Praialta Piranheira, Pará State, Brazil. Data were collected from adult and sapling trees in six forest fragments. Adult and sapling density was compared among fragment sizes by the Mann–Whitney test, while diameter distributions were compared by a summary statistic calculated using the scores of a PCA produced with the results of the binomial logit model between tree DBH and the cumulative DBH proportions. The density of adult trees of three species is similar among different-sized fragments. Only the saplings of C. cateniformis showed a significant difference in density among fragment sizes. The DBH distribution of adults, for all three species, seems to also not respond to fragmentation, since the differences in the DBH distribution curves among fragments were large. The results of this study suggest that in areas established for agroextractivism, all fragments (large and small) no longer have sustainable populations (except only one C. guianensis population), probably due to anthropic pressure exerted by agroextractivism. So, it is important to ensure the structural and environmental quality of the forest fragments for the conservation of the species. [ABSTRACT FROM AUTHOR]

Background: The growing human population around the world is creating an increased demand for food. In agricultural landscapes, forests are cleared and turned into agricultural land to produce more food. Increasing the productivity of agricultural land per unit area may prevent extreme forest degradation. Since many agricultural products are dependent on pollinators, it is possible to increase crop production by increasing the pollination rate in the agricultural landscapes. Pollinators are highly dependent on forest patches in agricultural landscapes. Therefore, by creating new forest patches around agricultural fields, we can increase the pollination rate, and thus the crop production. In this regard, estimating the effects of different scenarios of forest fragmentation helps us to find an optimized pattern of forest patches for increasing pollination in an agricultural landscape. Methods: To investigate the effect of different forest fragmentation scenarios on pollination, we used simulated agricultural landscapes, including different forest proportions and degrees of fragmentation. Using landscape metrics, we estimated the relationship between pollination and landscape structure for each landscape. Results: Our results showed that for increasing pollination, two significant factors should be considered: habitat amount and capacity of small patches to supply pollination. We found that when the capacity of small patches in supplying pollination was low, fragmented patterns of forest patches decreased pollination. With increasing capacity, landscapes with a high degree of forest fragmentation showed the highest levels of pollination. There was an exception for habitat amounts (the proportion of forest patches) less than 0.1 of the entire landscape where increasing edge density, aggregation, and the number of forest patches resulted in increasing pollination in all scenarios. Conclusion: This study encourages agriculturists and landscape planners to focus on increasing crop production per unit area by pollinators because it leads to biodiversity conservation and reduces socio-economic costs of land-use changes. We also suggest that to increase pollination in agricultural landscapes by creating new forest patches, special attention should be paid to the capacity of patches in supporting pollinators. [ABSTRACT FROM AUTHOR]

The plot-level decisions of land managers (i.e., farmers, ranchers, and forest owners) influence landscape-scale environmental outcomes for biodiversity in agricultural landscapes. The impacts of their decisions often develop in complex, non-additive ways that unfold over time and space. Behavioral science offers insights into ways decision-makers manage complexity, uncertainty, choice over time, and social influence. We review such insights to understand the plot-level conservation actions of farmers that impact biodiversity. To make these connections concrete, we provide a case study of the decision to adopt biodiversity management practices in the heavily cultivated region of the Central Valley, California, USA. We use results from a survey of 122 farmers in the region to test whether adoption is related to farm tenure arrangements or peer influence. We find farmers who are more sensitive to peer influence are three times more likely to adopt practices that support biodiversity, including wildflowers, native grasses, cover crops, hedgerows, and wetlands. This relationship could have important implications for how plot-level decisions aggregate to landscape-scale outcomes. Finally, we suggest priorities for future research and program design to integrate behavioral science into biodiversity conservation in agricultural landscapes. By considering land managers' plot-level conservation decisions with the lens of behavioral science, we identify barriers and opportunities to promote environmental benefits. [ABSTRACT FROM AUTHOR]

Trees are important components of agricultural landscapes in different parts of Ethiopia, and information on their type, diversity and distribution in sub-humid agroecologies is essential for designing interventions. A study was conducted to evaluate tree diversity and their spatial patterns in agricultural landscapes under different land use categories in four selected sub-humid sites in Western Oromia, Ethiopia. Tree inventory was conducted on 100 homesteads (19 ha), 18 crop lands (35 ha) and 11 grazing lands (5.5 ha) belonging to 100 randomly selected households. A total of 82 tree species were identified: 67 in the homesteads, 52 in the crop lands and 29 in the grazing lands. The density of trees varied from 68 trees per ha in crop lands to 801 trees per ha in homesteads. Diversity indices revealed that homestead was the most diverse with Shannon index of 2.42, and Simpson index of 0.84. The density of trees among the tree communities in the four sites varied from 133 in Bako Tibe to 476 in Jima Arjo, but not any one of the sites had more diverse tree community as revealed by the Rènyi diversity profiles analysis. The three dominant tree species in the agricultural landscapes were Eucalyptus camaldulensis, Vernonia amygdalina and Cordia africana. Pearson correlation analysis showed that high tree species density, richness and diversity had high association with homesteads than with crop lands and grazing lands. It also revealed significant positive correlations between land size and evenness, and latitude and evenness whereas there were significant negative correlations between family size and Shannon diversity index, and land size and tree density. The majority (81.6%) of the trees were established through plantation and only 18.4% were regenerated naturally. The proportion of planted trees varied from 68% in Gobu Seyo to 94.1% in Guto Gida. The study showed that agricultural landscapes harbour high diversity of tree species with a spatial pattern, and increasing the tree cover with focus in the crop lands is essential for improved resilience of the agricultural systems and for circa-situm conservation of biodiversity. [ABSTRACT FROM AUTHOR]

The information on both the catchment land use and catchment area has the potential to be adopted into the conservation and management of ponds. There have been, however, few attempts to describe the effects of land use acting at various spatial scales on ponds and the studies were restricted to specific categories of ponds. This paper presents a study on 92 ponds distributed over a broad range of environmental conditions in Central Europe. We combined an extensive field survey and a detailed analysis of sediment and water chemistry with GIS-derived data to estimate the relationship between the area of the ponds and the area of their catchments, and to assess the relationship between pond physico-chemical conditions and land use across multiple spatial scales. Relating the area of ponds to the area of their catchments, we found a significant positive relationship ( r = 0.72). Considering land use effects on pond conditions, catchment-scale land use was the only significant spatial extent influencing the physico-chemical conditions. Most notably, the proportion of intensively exploited land (arable land, urban areas) in the catchment scale was positively correlated with the deterioration of pond physico-chemical properties. The results of the study suggest that effective conservation of ponds cannot be achieved merely through the management of narrow buffer zones around them but should involve maintenance of less intensive land use within the whole catchment. Moreover, easily accessible catchment-scale GIS data could serve as a decision-support tool for cost-effective management strategies aimed at improving pond physico-chemical conditions. [ABSTRACT FROM AUTHOR]

We develop a landscape stewardship classification which distinguishes between farmers' understanding of landscape stewardship, their landscape values, and land management actions. Forty semi-structured interviews were conducted with small-holder (<5 acres), medium-holders (5-100 acres), and large-holders (>100 acres) in South-West Devon, UK. Thematic analysis revealed four types of stewardship understandings: (1) an environmental frame which emphasized the farmers' role in conserving or restoring wildlife; (2) a primary production frame which emphasized the farmers' role in taking care of primary production assets; (3) a holistic frame focusing on farmers' role as a conservationist, primary producer, and manager of a range of landscape values, and; (4) an instrumental frame focusing on the financial benefits associated with compliance with agri-environmental schemes. We compare the landscape values and land management actions that emerged across stewardship types, and discuss the global implications of the landscape stewardship classification for the engagement of farmers in landscape management. [ABSTRACT FROM AUTHOR]

Context: The identification of habitat structures with biologically meaningful links to habitat quality has enabled an increased understanding of wildlife distributions in fragmented landscapes. However, knowledge is lacking of where these structures occur in the landscape. Objectives: For a broad-scale agricultural landscape, we investigated how the occurrence and abundance of wildlife habitat structures is related to abiotic conditions and land management practices, and whether this differed between old growth and regrowth woodland. Methods: We used generalised linear mixed models to investigate the distribution of eight habitat structures in the South-West Slopes bioregion of south-eastern Australia. Results: Only one habitat structure, canopy depth, was related to abiotic conditions alone, whereas only leaf litter cover was related to land management practices only. Each of the other structures (abundance of logs, large trees, hollow-bearing trees, mid-sized trees and dead trees, and amount of native grass cover) was related to a combination and/or interaction of abiotic conditions and land management practices. Old growth woodland had higher log, large tree and hollow-bearing tree abundance, whereas regrowth woodland had higher mid-sized tree and dead tree abundance. Conclusions: Our findings inform key management prescriptions that can be used to improve conservation efforts so they have strong, quantifiable effects on wildlife habitat in temperate agricultural landscapes. Our case study shows that by understanding how management actions in specific abiotic conditions lead to the increased occurrence or abundance of particular habitat structures, management can be spatially targeted to alternative conservation strategies relevant to the landscape of interest. [ABSTRACT FROM AUTHOR]

Cork oak landscapes are considered a model for the integration of sustainable land-use and biodiversity conservation. These traditional cultural landscapes, shaped through centuries, are in sharp decline in the Iberian Peninsula due to the polarization of their usage: from agricultural intensification to land abandonment. This study presents an in-depth analysis of the main drivers affecting cork oak landscapes' management and structure in Berrocal, Huelva Province, Spain since 1940. Results show that the main causes for the decline of these landscapes has been the abandonment of the traditional multi-functionality of the dehesa, largely driven by demographic changes, and the increasing occurrence of major disturbances, such as wildfires, drought and diseases. This case illustrates how the abandonment of obsolete land-uses transforms traditional landscapes, sparking questions about what the goals of traditional landscape conservation should be and about possible alternative management options, their associated conservation benefits and risks. [ABSTRACT FROM AUTHOR]

Landscapes intensively farmed over a long time period represent a threat for natural habitats and high levels of biodiversity. Information on the historical land use and spatial changes of natural habitats can help to explain the causes of a number of contemporary phenomena, which are important for the development of effective conservation and ecosystem management. This case study from the Czech Republic shows that archival written sources describing landscape quality, including vegetation cover, allow the reclassification of old maps to the level of natural habitat categories (sensu Natura 2000), with the aim of analyzing historic changes in land cover. Significant natural habitat decreases began by the middle of the 19th century. Over the course of 250 years, this area of formerly widespread natural wet meadows has declined by 99 %. An area of water vegetation was reduced by 95 %, willow carrs by 98 %, and a mosaic of willow carrs, wet Cirsium meadow, and alder carrs has decreased by 100 %. These decreases were caused by the conversion of meadows, pastures, and ponds into arable lands. Areas of oak-hornbeam forest, acidophilous oak forest, and thermophilous oak forest were primarily converted into monocultures of coniferous trees. Similarly, the areas with alluvial forests decreased. We conclude that old maps and other archive materials, despite their coarse accuracy, can serve as useful tools for disclosing natural habitat changes and their causes, providing a foundation for formulating biodiversity conservation strategies. [ABSTRACT FROM AUTHOR]

The expansion and intensification of agriculture is a major driver of forest shrinkage and biodiversity loss, and the threat to biodiversity is projected to increase with increased population growth and food demand; therefore, food production with a minimal ecological footprint is an important development goal. Agroforestry, as practiced in the hilly populated agricultural landscape of the central Himalaya, reflects a scenario of land sharing with a balance in the trade-offs between forest management and tree protection/retention in private farmlands. We aim to assess whether agroforestry has contributed to conserving tree species diversity. We compare different measures of tree species diversity and trends in richness with elevation between farmland and forest using empirical data gathered from 1000 to 1800 masl in the mid-hills of central Nepal. We find that farmlands are consistently richer in tree species than forest. Our analysis further reveals that in spite of many shared species between forest and farmland they are different in composition, due to differences in the relative abundance of shared species and the presence of unique species in each land use types. We shed light on the ecological and management-related drivers that enhance tree species richness in the populated farmlands. We highlight that an agricultural landscape can complement, but not necessarily substitute, the biodiversity conservation goal of protected areas by providing alternative habitats, refugia and landscape connectivity for floral and faunal species. We underscore that biodiversity conservation strategies and landscape planning should acknowledge the role of agroforestry in maintaining trees and associated biodiversity, and provisioning ecosystem services. [ABSTRACT FROM AUTHOR]

Landscape approaches are widely applied in attempts to reconcile tradeoffs amongst different actors with conflicting demands on land and water resources. Key principles for landscape approaches have been endorsed by inter-governmental processes dealing with climate change mitigation and adaptation and biodiversity conservation. We review experiences from seven landscapes located in the Congo Basin, Eastern Indonesia and Northern Australia. Landscape initiatives were applied in situations where large-scale extractive industries, local peoples' livelihoods and global biodiversity objectives were in conflict. We found that common published principles for landscape approaches are not applied systematically in the areas studied. Practitioners draw upon landscape approach principles selectively and adapt them to deal with local conditions. We consider that landscape approaches do not provide silver bullet solutions to these situations nor do they provide an operational framework for large-scale land management. Landscape approaches do, however, provide an organising framework for disentangling the complexity of the landscape and facilitating the investigation of impacts of different courses of action. They enable alternative scenarios for what future landscapes might look like to be investigated and they create the space for multi-stakeholder negotiations. Outcomes from landscape scale approaches are determined by the power differentials amongst stakeholders and the existence, or otherwise, of functional institutions to take decisions and enforce agreements. Landscape approaches cannot overcome disparities in power or entrenched interests nor can they substitute for institutions with authority to establish and legitimise property and resource rights. They can, however, provide a mechanism around which civil society can be mobilised to achieve better land use outcomes. Landscape approaches are successful when they have strong leadership, sustained long-term and facilitated processes, good governance, adequate budgets and adequate metrics for assessing progress. Private sector engagement is necessary and all parties must have sufficient shared interest in outcomes to motivate their participation. [ABSTRACT FROM AUTHOR]

This article presents a study of shifting cultivation in Guinea-Bissau, illustrating the diversity, flexibility and resilience of these multifold agricultural practices and of its non-linear relation with deforestation and biodiversity conservation. The comparative analysis of the country's three social and agro-ecological regions shows that the shortest fallows are not associated with the longest cultivation periods and with higher population densities. Further, the fast-track conversion of shifting cultivation into permanent agriculture with orchards is similar in the three regions, and is not occurring in response to land scarcity, shorter fallows and decreasing soil fertility. The article, then, adds depth to the understanding of the complexity of shifting cultivation in Africa and of its multiple routes of transformation into permanent agriculture. [ABSTRACT FROM AUTHOR]