Deborah Stinner

Agroecosystem biodiversity: matching production and conservation biology

Abstract A review of the existing literature on biodiversity connected with agricultural activities has been developed, and the possible sustainable alternatives have been looked into. Following recent evaluations, only one-twentieth to one-sixtieth of the planets species have yet been described and most of these will be lost if the destruction of the environment continues at its present rate. Most of the terrestrial environment (up to 95%) is affected by human activities including agriculture and the terrestrial habitats provide up to 98% of human food on the planet. Sustainable strategies in food production in agriculture improve the existing biodiversity and include the following items: increased porosity of the landscape through proper management of natural vegetation, better use and recycling of organic residues, introduction of integrated farming systems, reduced tillage, rotation, biological control, increased number of biota involved in human food-webs.

Diversity of soil fauna in the canopy and forest floor of a Venezuelan cloud forest

Arboreal and terresterial soil and lilter were sampled for macro-and microinvertebrates at two locations in a Venezuelan cloud forest. Fauna were most abundant in forest floor soil and associated litter. However, media suspended in the canopy and particularly those trapped in bromeliad shoots were most densely populated, while the diversities of the arboreal and terrestrial soil fauna were indistinguishable. Rates of leaf litter decomposition in the arboreal and terrestrial soils were similar, but the arboreal soils contained higher concentrations of mineral nutrients and carbon. Implications of these findings for the definition of soil in humid tropical forests, and related differences between temperate and tropical forests are discussed. The similarities in diversity and differences in species composition between arboreal and terrestrial soil fauna raise questions concerning the evolution of tropical soil fauna, as well as the estimate of global biotic diversity.

Biodiversity as an organizing principle in agroecosystem management: Case studies of holistic resource management practitioners in the USA

Abstract Holistic Resource Management (HRM) is a process of goal setting, decision making and monitoring which integrates social, ecological and economic factors. Biodiversity enhancement is a fundamental principle in HRM and students are taught that biodiversity is the foundation of sustainable profit. In the HRM process, practitioners develop a holistic goal which includes: (1) quality of life values, (2) forms of production to support those values, and (3) landscape planning, which should protect and enhance biodiversity and support ecosystem processes of succession, energy flow, hydrological and nutrient cycling. We present an overview of the HRM model and results of interviews with 25 HRM farmers and ranchers from across the USA in which perceptions and experiences with respect to the role of biodiversity in the sustainability of their operations were explored. An ethnographic approach and qualitative research methods were used in the interviews. While only 9% of the interviewees reported thinking about biodiversity in the context of their operations before being exposed to HRM, now all of them think biodiversity is important to the sustainability of their famrs and ranches. Of the people interviewed, 95% perceived increases in biodiversity (particularly with respect to plants) and 80% perceived increase in profits from their land since HRM began influencing their decisions. In addition to perceiving increases in biodiversity, all of the interviewees reported observing indications of positive changes in some of the ecosystem processes on their farms or ranches. In addition, 91% of the interviewees reported improvements in their quality of life because of changes in their time budgets. Three of the interviewees who had quantitative data on changes in numbers of plant species and economic indicators are discussed in detail. We conclude that holistic management approaches like HRM are worthy of further study.

Implications of Land Use Changes on Carbon Dynamics and Sequestration—Evaluation from Forestry Datasets, India

Forests and soils are a major sink of carbon, and land use changes can affect the magnitude of above ground and below ground carbon stores and the net flux of carbon between the land and the atmosphere. Studies on methods for examining the future consequences of changes in patterns of land use change and carbon flux gains importance, as they provide different options for CO2 mitigation strategies. In this study, a simulation approach combining Markov chain processes and carbon pools for forests and soils has been implemented to study the carbon flows over a period of time. Markov chains have been computed by converting the land use change and forestry data of India from 1997 to 1999 into a matrix of conditional probabilities reflecting the changes from one class at time t to another class time t+1. Results from Markov modeling suggested Indian forests as a potential sink for 0.94 Gt carbon, with an increase in dense forest area of about 75.93 Mha and decrease of about 3.4 Mha and 5.0 Mha in open and scrub forests, if similar land use changes that occurred during 1997–1999 would continue. The limiting probabilities suggested 34.27 percent as dense forest, 6.90 as open forest, 0.4 percent mangrove forest, 0.1 percent scrub and 58 percent as non-forest area. Although Indian forests are found to be a potential carbon sink, analysis of results from transition probabilities for different years till 2050 suggests that, the forests will continue to be a source of about 20.59 MtC to the atmosphere. The implications of these results in the context of increasing anthropogenic pressure on open and scrub forests and their contribution to carbon source from land use change and forestry sector are discussed. Some of the mitigation aspects to reduce greenhouse gas emissions from land use change and forestry sector in India are also reviewed in the study.

Learning Sustainable Development with a Farm Enterprise and Its Community

ABSTRACT Model social processes useful in facilitating sustainable development are advanced from our team experiences with a case study. The processes are: learn how to learn as a team and community, use a model process that reveals shared interests and leverageable points, and then facilitate local stakeholders in developmental action. The case provided the team the opportunity to learn to describe and comprehend the case agroecosystem as a whole–natural elements and social relationships. Dialogue among stakeholders created an awareness and clarity of leverageable issues. Team engagement with local stakeholders facilitated efforts to organize, integrate information and motivate developmental action. Case issue lessons were: farmers need information to transition to more sustainable forms of agriculture, institutional mechanisms are needed to support the development of new markets, consumers need information on the benefits of using agriculural products that enhance their environment, and the public needs to share responsibility for food safety and health rather than generating more governmental regulation. This sustainable development model process is presented to inform other farm-community change efforts.