Like most farmers in the Indonesian province of Jambi, Abdul Roni used to make a meagre living from his rubber gardens, just enough to keep his family in clothes and food, but not enough to pay for the children’s education or much else. However, his life began to change for the better when scientists from the World Agroforestry Centre encouraged him to replace some of his low-yielding ‘jungle rubber’ gardens with a different form of rubber agroforestry. “I changed the way I manage my land,” he says. “In 1996, I cleared the jungle rubber, planted high-yielding clonal varieties and learned how to space my trees, weed between the rows and control disease. I also started to use fertilizer, something I’d never done in the past.” Five years later, he began to tap his young rubber trees, and today his yields are three times higher than they were before. He has also planted timber trees among the rubber and these will provide wood to build homes for his children.
Tag: biodiversity
Agricultural intensification, soil biodiversity and agroecosystem function
Intensification of agriculture in the tropics has resulted from a shortage of farmland and insufficient food production to satisfy the needs of an expanding population. Many tropical farmers are challenged by the prospect of intensifying their production while sustaining or improving the fertility and productivity of soils with only locally available natural resources. The waste products of plant and animal production represent some of the most abundant natural resources available for use by tropical farmers to achieve these goals. The efficient use and management of these resources depends on understanding the role that decomposer biota play in regulating the structure and function of agricultural ecosystems. Furthermore, the development of agricultural management practices which promote the beneficial attributes of these organisms will be essential to sustaining the productivity and environmental integrity of tropical agriculture. Finally, understanding the role of biodiversity among decomposer biota in maintaining the functional properties of tropical agricultural ecosystems is critical to achieving this goal.The objective of this review is to further that understanding by describing the taxonomic and functional diversity of decomposer biota in the tropics and evaluating known links between their diversity and the function of agricultural ecosystems. We further describe the effects of changing land-use and agricultural intensification on the structure and diversity of decomposer communities in the tropics and suggest some priorities for future research
Application of consensus theory to formalize expert evaluations of plant species distribution models
AimApplication of environmental envelope modelling (EEM) for conservation planning requires careful validation. Opinions of experts who have worked with species of interest in the field can be a valuable and independent information source to validate EEM because of their firsthand experience with species occurrence and absence. However, their use in model validation is limited because of the subjectivity of their feedback. In this study, we present a method on the basis of cultural consensus theory to formalize expert model evaluations.MethodsWe developed, for five tree species, distribution models with nine different variable combinations and Maxent EEM software. Species specialists validated the generated distribution maps through an online Google Earth interface with the scores from Invalid to Excellent. Experts were also asked about the commission and omission errors of the distribution models they evaluated. We weighted expert scores according to consensus theory. These values were used to obtain a final average expert score for each of the produced distribution models. The consensusweighted expert scores were compared with unweighted scores and correlated to four conventional model performance parameters after crossvalidation with test data: Area Under Curve (AUC), maximum Kappa, commission error and omission error.ResultsThe median consensusweighted expert score of all species–variable combinations was close to Fair. In general, experts that reached more consensus with peers were more positive about the EEM outcomes, compared to those that had more opposite judgements. Both consensusweighted and unweighted scores were significantly correlated to corresponding AUC, maximum Kappa and commission error values, but not to omission errors. More than half of the experts indicated that the distribution model they considered best included areas where the species is known to be absent. One third also indicated areas of species presence that were omitted by the model.ConclusionsOur results indicate that experts are fairly positive about EEM outcomes. This is encouraging, but EEM application for conservation actions remains limited according to them. Methods to formalize expert knowledge allow a wider use of this information in model validation and improvement, and they complement conventional validation methods of presenceonly modelling. Online GIS and survey applications facilitate the consultation of experts.
Managing biological and genetic diversity in tropical agroforestry
The issues of biological and genetic diversity management in agroforestry are extremely complex. This paper focuses on genetic diversity management and its implications for sustainable agroforestry systems in the tropics, and presents an analysis of the role and importance of inter- and intra-specific diversity in agroforestry. Diversity within and between tree species in traditional agroforestry systems and modern agroforestry technologies in the tropics is assessed, with a view to understanding the functional elements within them and assessing the role and place of diversity. The assessment shows that although the practice of agroforestry has been a diversity management and conservation system, research in agroforestry over time has de-emphasized the diversity element
Biodiversity and Human Livelihood Crises in the Malay Archipelago
The unprecedented destruction of tropical habitats is precipitating a catastrophic biodiversity crisis (e.g., Brook et al. 2003) and adversely affecting humanity through the loss of nature’s services, including climate regulation, flood protection, and crop pollination (Balmford & Bond 2005). The close link between human well-being and healthy ecosystems has recently been demonstrated by the devastating Asian tsunami, El Nino-induced fires, and ˜ the emergence of noxious zoonotic diseases (Danielsen et al. 2005; Sodhi & Brook 2006). Nevertheless, the conservation of tropical biodiversity has been difficult to achieve, as witnessed by the serious shortfall in protectedarea coverage (Rodrigues et al. 2004). Most areas with exceptionally rich but imperiled biodiversity are inhabited by rural people who are among the poorest in the world. The communities they comprise often extract natural resources from protected biodiversity-rich areas, disputing the legitimacy of protection. The apparent conflict between protection of biodiversity and development of rural livelihoods has fueled long-standing debates be tween conservation biologists and social scientists (e.g., Wilkie et al. 2006). Biologists often consider some human activities as compromising biodiversity protection, whereas some social scientists view certain biodiversityprotection efforts as infringing on the rights of local peoples and jeopardizing their livelihoods (Terborgh 2000; Brechin et al. 2003). The tropics include many postcolonial, emerging nations, where the failure of governments and their institutions to address environmental degradation and social injustices exacerbates the conflicts (Sodhi & Brook 2006)
Rethinking the effectiveness of public protected areas in Southwestern China
It is internationally recognized that conservation policies should respect indigenous cultures and consider the livelihoods of people affected by conservation restrictions. Countering this are concerns that human occupation and use of natural reserves is incompatible with conservation aims. But in China today the continued use and management of natural areas by local communities is likely to deliver better conservation outcomes than the current drive to establish public protected areas. The effectiveness of many protected areas in China is compromised by institutional conflicts, lack of ongoing financial and technical support, confusion between the objectives of generating revenue and conservation, dubious scientific definitions, lack of community trust in policies, and obscure user rights and land tenures. Southwestern China-one of the most biologically and ethnologically diverse areas on Earth-is a good illustration of a place where culture and biological diversity are closely linked. The indigenous people in this area have shown that local livelihood practices can be advantageous for the long-term maintenance of conservation goals. Rather than creating new protected areas, we argue that China is better advised to support ongoing sustainable use of natural areas by the people who have lived and nurtured these environments for generations.
Warfare in biodiversity hotspots
Conservation efforts are only as sustainable as the social and political context within which they take place. The weakening or collapse of sociopolitical frameworks during wartime can lead to habitat destruction and the erosion of conservation policies, but in some cases, may also confer ecological benefits through altered settlement patterns and reduced resource exploitation. Over 90% of the major armed conflicts between 1950 and 2000 occurred within countries containing biodiversity hotspots, and more than 80% took place directly within hotspot areas. Less than one-third of the 34 recognized hotspots escaped significant conflict during this period, and most suffered repeated episodes of violence. This pattern was remarkably consistent over these 5 decades. Evidence from the war-torn Eastern Afromontane hotspot suggests that biodiversity conservation is improved when international nongovernmental organizations support local protected area staff and remain engaged throughout the conflict. With biodiversity hotspots concentrated in politically volatile regions, the conservation community must maintain continuous involvement during periods of war, and biodiversity conservation should be incorporated into military, reconstruction, and humanitarian programs in the world’s conflict zones.
The melting Himalayas: cascading effects of climate change on water, biodiversity, and livelihoods
The Greater Himalayas hold the largest mass of ice outside polar regions and are the source of the 10 largest rivers in Asia. Rapid reduction in the volume of Himalayan glaciers due to climate change is occurring. The cascading effects of rising temperatures and loss of ice and snow in the region are affecting, for example, water availability (amounts, seasonality), biodiversity (endemic species, predator-prey relations), ecosystem boundary shifts (tree-line movements, high-elevation ecosystem changes), and global feedbacks (monsoonal shifts, loss of soil carbon). Climate change will also have environmental and social impacts that will likely increase uncertainty in water supplies and agricultural production for human populations across Asia. A common understanding of climate change needs to be developed through regional and local-scale research so that mitigation and adaptation strategies can be identified and implemented. The challenges brought about by climate change in the Greater Himalayas can only be addressed through increased regional collaboration in scientific research and policy making.
Payment for environmental services: interactions with property rights and collective action
Global climate change and environmental degradation highlight the need for institutions of sustainability. In particular, there is increased interest in the potential of payments for environmental services (PES) to improve incentives for sustainable land management. Although smallholder land users can be efficient producers of environmental services of value to larger communities and societies, experience shows that the international and national institutions that govern PES are often designed in ways that entail transaction costs that cannot be feasibly met by individual smallholders. This chapter presents a conceptual framework to examine the inter-linkages between property rights, collective action, payment for environmental services, and the welfare of smallholder land users, examining how these play out in the contexts of carbon sequestration, biodiversity, and watershed functions. Greater consideration of the linkages between PES and other rural institutions can lead to more equitable outcomes, particularly by (1) suggesting how collective action can be used to overcome transaction costs and barriers to participation by smallholders and (2) identifying mechanisms through which managers of small private parcels or areas of common property can be rewarded for environmental stewardship through PES.
Contribution of agroforestry to biodiversity and livelihoods improvement in rural communities of Southern African regions
It has been widely documented that the traditional farming system of shift- ing cultivation contributes to huge annual losses of forest cover, altering the structure and distribution of species resulting in loss of biodiversity. On the other hand, formal institutional approaches to natural forest biodiversity con- servation focused on protecting the tree species in parks and reserves while neglecting their conservation in farming systems. Improved agroforestry sys- tems (AFS) such as improved fallows that mimic shifting cultivation and other AFS provide benefits that contribute to rural livelihoods, improved socio- economic status and ecosystem functioning of land use systems. Recently, there is an increasing recognition of the contribution of agroforestry to im- prove ecosystem services and livelihoods especially in rural areas. Compared with subsistence agriculture, AFS provides added benefit by generating cash income from the marketing of diverse products. In southern Africa, research that aims to addressed biodiversity and socio-economic issues includes domes- tication of diverse priority indigenous fruit tree species; and the evaluation of soil fertility replenishing Agroforestry technologies. This paper discusses the contribution of the natural forest resource and AFS to the improvement of the socio-economic livelihoods of smallholder farmers and the promotion of the conservation of biodiversity drawing on evidence from research conducted in southern Africa over the last two decades.