10 | IAASTD Global Report

Ecological changes induced by all types of agriculture

Agricultural activities require change of the natural ecosystem to an agricultural system that is oriented towards human use. This concerns local agricultural practices as well as industrial models and all forms in between. Deforestation was, and still is, the first major step to convert primary tree vegetation into cropland or grazing land, thereby reducing biological diversity in most instances. Other environmental impacts relate to soil, physical, biological and chemical degradation and problems of water quality and quantity.

     On the one hand, even in traditional agricultural systems cropping involves tillage operations that may cause accelerated soil erosion. Soil degradation is highest on cropland, but it also affects grazing land and even forest plantations and other agricultural activities (Hurni et al., 1996). Smallscale farming can damage the environment, particularly when practiced under increasing population pressure and with scarce suitable land, involving shortened fallow periods and expansion of cropland areas into unsuitable environmental situations such as steep slopes. This process was particularly accelerated during the past 100 years due to the expansion of farming, despite the emergence of agroecological practices and widespread efforts to introduce sustainable land management technologies on small farms (Liniger and Critchley, 2007).

     On the other hand, the advancement of industrial models in agriculture has promoted the simplification of agroecosystems, with reductions in the number of and variability within species. Increased specialization at the field, farm, and landscape levels produces monocultures that potentially increase environmental risks because they reduce biodiversity, ecosystem functions and ecological resilience, and they may be highly vulnerable to climate change. These systems have both benefited and endangered human health and the environment in many industrial countries. While industrial production systems yield large volumes of agricultural commodities with relatively small amounts of labor, they are often costly in terms of human health (Wesseling et al., 1997; Antle et al., 1998; Cole et al., 2002), have additional negative environmental impacts, and are frequently inefficient in terms of energy use. Runoff and seepage of synthetic fertilizers and concentrated sources of livestock waste damage aquifers, rivers, lakes, and even oceans—with costly effects on drinking water quality, fish habitat, safety of aquatic food, and recreational amenities (FAO, 1996a; WWAP, 2003; FAO, 2006b; CA, 2007). This is occurring particularly rapidly in some emerging industrialized countries. However, in countries with increasing industrial production one may also observe more effective food regulation and safety protocols, providing enhanced health protection against foodborne illness. Commercial pesticides often affect non-target organisms and their habitats, and especially when used without strict attention to recommended usage and safety protocols, can negatively affect the health of farm workers (WWAP, 2003). The international transportation of crops, livestock and food products has promoted the global spread of agricultural pests and disease organisms. Many recent significant disease outbreaks have been due to informal, unregulated trade, smuggling, or the industrial restructuring of food systems. The global atmospheric


transport of agricultural pollutants, including pesticides, the breakdown products of other agrichemicals, and greenhouse gases, means that environmental costs are also borne by populations far removed from sites of production (Commoner, 1990; UNEP, 2005).

Food security and food sovereignty

Improvement of rural livelihoods, human health and nutrition. Livelihoods are a way of characterizing the resources and strategies individuals and households use to meet their needs and accomplish their goals. Livelihoods are often described in terms of people, their capabilities and their means of living (Chambers and Conway, 1991). Livelihoods encompass income as well as the tangible and intangible resources used by the household to generate income. Livelihoods are basically about choices regarding how, given their natural and institutional environments, households combine resources in different production and exchange activities, generate income, meet various needs and goals, and adjust resource endowments to repeat the process.

     Food security exists when all people of a given spatial unit, at all times, have physical and economic access to safe and nutritious food that is sufficient to meet their dietary needs and food preferences for an active and healthy life, and is obtained in a socially acceptable and ecologically sustainable manner (WFS, 1996). Food sovereignty is defined as the right of peoples and sovereign states to democratically determine their own agricultural and food policies. Food sovereignty, the right to food, equitable distribution of food, and the building of sufficient reserves to ensure food security for unexpected events of unpredictable duration and extent (such as hurricanes or droughts), have so far been strategies at the national and international levels with obvious advantages (Sen and Drèze, 1990, 1991). Assumptions that national average food production figures can indicate food security are belied by internal distribution constraints, political limitations on access, inabilities to purchase available food, overconsumption in segments of a population, policies which encourage farmers to shift from family food production to cash crops, crop failure, storage losses, and a range of other factors. Unless all persons feel food secure and are confident in their knowledge of the quality, quantity, and reliability of their food supply, global food security averages cannot be extrapolated to specific cases. The ability to access adequate food covers industrial and cash-cropping farmers, subsistence farmers during crop failures, and non-agriculturists. Access can be limited by local storage failures, low purchasing power, and corrupt or inefficient distribution mechanisms, among other factors. Quality of food, in terms of its nutritional value, is determined by freshness or processing and handling techniques, variety, and chemical composition. A new component in the food security debate is increasing malnutrition in agricultural areas where cash crops, including biofuel crops, replace local food crops.

     Food insecurity has been defined in terms of availability, access, stability and utilization. Food insecurity occurs when there is insufficient food over a limited period of time, such as a "hungry season" prior to harvest, or for extended or recurring periods. Food insecurity may affect individuals, households, specific population groups or a wider popula-