Biotic interactions, ecological knowledge and agriculture

Abstract

This paper discusses biotic interactions in agroecosystems and how they may be manipulated to support crop productivity and environmental health by provision of ecosystem services such as weed, pest and disease management, nutrient cycling and biodiversity conservation. Important elements for understanding biotic interactions include consideration of the effects of diversity, species composition and food web structure on ecosystem processes; the impacts of timing, frequency and intensity of disturbance; and the importance of multitrophic interactions. All of these elements need to be considered at multiple scales that depend in part on the range of the movement of the organisms involved. These issues are first discussed in general, followed by an examination of the application of these concepts in agricultural management. The potential for a greater use of ecological management approaches is high; however, owing to the nature of complex interactions in ecosystems, there is some inherent unpredictability about responses to management interventions under different conditions. Such uncertainty needs to be accommodated in the development of recommendations for farm management. This requires an increased emphasis on the effective synthesis of complex and often apparently contradictory information and on field-based adaptive research, monitoring and social learning by farmer/researcher collaborations.

Agricultural sustainability: concepts, principles and evidence

“…One system may be said to be more sustainable relative to another if its negative externalities are lower. Monetary criteria do, though, only capture some of the values of agricultural systems and the resources upon which they impinge (Carson 2000), and so choices may depend on wider questions about the sustainability of farm practices (on farm, in field) and the sustainability of whole landscapes (interactions between agricultural and wild habitats; Green et al 2005;Shennan 2008;Waage & Mumford 2008;Wade et al 2008).…”

“…Mature ecosystems are now known to be not stable and unchanging, but in a state of dynamic equilibrium that buffers against large shocks and stresses. Modern agroecosystems have weak resilience, and for transitions towards sustainability need to focus on structures and functions that improve resilience (Holling et al 1998;Folke 2006;Shennan 2008).…”

Wicked Problems and Applied Economics

“…Consider environmental management of agricultural lands. Because system responses (including social systems responses) are fraught with uncertainties and significant unknowns (e.g., lags, thresholds, cultural influences) as well as confounding influences of spatial and temporal fluctuations and variability (e.g., climate changes, land use changes), no research can predict with certainty the results of large landscape changes on the environment or agricultural sector (Shennan 2008). Thus, there is a strong argument that policies should be viewed as experiments; basically they provide "learning by doing" but with extensive monitoring of environmental outcomes that then provides information for adaptive management (Watzin 2007).…”

Farmers Participatory Evaluation on Performance of Red gram + Soybean Intercropping vis-a-vis Sole Cotton under Rainfed Medium Soils of Telangana

“…Apart from these, the practice of intercropping also reduces the population density of insects-pests as the intercrop may not serve as their host (Viglizzo et al, 2012). Intercropping also demonstrate weed control advantages over sole crops as intercrops are more effective than sole crops and usurp resources from weeds or suppress weed growth through allelopathy (Shennan, 2008). Soybean due to its trade and industrial significance and adaptability to varied agro-climatic conditions occupies greater part of potential cultivated area as an integral part of prevailing cropping systems in India and world over.…”