Environmental impacts of organic farming.

Abstract

This chapter provides an overview of the main indicators of environmental impact, i.e., biodiversity, landscape, soil, ground and surface water, climate and air, and energy. The discussion of environmental impacts is structured by six main sectors. Significant interrelationships were observed between these sectors. The effects of biological diversity are detailed for the following three aspects: genetic diversity, species diversity (floral and faunal) and habitat diversity. The soil aspect focuses on organic matter content, biological activity, nutrient cycles and soil erosion. Different sources of ground and surface water pollution (viz., leaching of nutrients, fertilizers, pesticides and pathogens) are also discussed in detail. The harmful effects of global climatic change on the environment and on plant production are discussed. Finally, the energy intensity and efficiency as indicators to measure and evaluate energy use are discussed.

Comparison of organic and conventional farms: challenging ecologists to make biodiversity functional

“…A recent position paper cautioned that critical ecosystem services such as pollination and pest control for food production both support and depend on biodiversity (MA 2003). The same linkages have been expressed for organic farming operations with higher biodiversity than conventional farms (Kasperczyk and Knickel 2006; Letourneau and van Bruggen 2006).…”

“…Certification regulations and government mandates commonly mention biodiversity as a goal or standard for organic agriculture (FAO 1999; Kasperezyk and Knickel 2006). Recent meta‐analyses and subsequent comparisons of organic and conventional farms show that organic agriculture can promote biodiversity in general and the diversity of predatory arthropods in particular.…”

Farming practices change food web structures in cereal aphid–parasitoid–hyperparasitoid communities

“…In agricultural landscapes, increased applications of fertilizers and pesticides have led to a degradation of habitats and losses in the biodiversity of several taxonomic groups. Organic farming, as an alternative to conventional farming, has been suggested to counteract such changes in community structure and function (reviewed by Bengtsson et al 2005; Hole et al 2005; Kasperczyk and Knickel 2006). Additionally, the insurance hypothesis predicts that a high diversity of natural enemies ensures the functioning of biological control because the larger number of species provide a greater guarantee that some species will maintain functioning if others fail in situations of environmental fluctuations (Yachi and Loreau 1999).…”

Economics of organically managed and conventional potato production systems in Atlantic Canada

“…Little evaluation of energy use in precision agriculture has been conducted; however, studies have consistently shown that application of any synthetic nitrogen fertiliser reduces energy efficiency when compared to organic systems that use manure or legumes as a nitrogen source (Aubert et al, 2003;Soil Association, 2006;Kasperczyk et al, 2006;Pimentel, 2006). A study from the Netherlands suggests that precision technology can reduce fertiliser input without sacrificing yields, but energy use in this system has not been evaluated (Koopmans et al, 2005).…”

“…There is an extensive body of research devoted to many environmental, social, and economic comparisons of organic and conventional agricultural systems. Various studies have compared the nutritional levels, yield, net income, quality of farmers' lives, and a variety of environmental impacts such as farmland biodiversity, soil quality, nutrient leaching, global warming potential, area of land used, and production in years with extreme weather conditions such as drought (Lotter, 2003;Kasperczyk et al, 2006;Stolze et al, 2000). This analysis does not aim to tackle the myriad factors on which these two systems can be compared.…”