DE LAS OBLIGACIONES; LOS DERECHOS; CAUSAS DE RESPONSABILIDAD; Y SANCIONES

This section looks at the landscape level to show how different kinds of land uses (including small-scale farming and natural ecosystems) influence each other’s functioning and sustainability. A landscape can be described as a mosaic of local ecosystems with a particular pattern of topography, vegetation, land use and settlement, over a kilometres-wide area. Ecosystems are a dynamic complex of plants, animals and micro-organism communities and their physical environment interacting as a functional unit in a certain place. Ecosystems make up big natural systems such as grasslands, mangroves, coral reefs and tropical forests; but even farms are often referred to as “agro-ecosystems”.

Landscapes constantly evolve under all sorts of pressures and these changes introduce new opportunities or impose restrictions on farms. For example, the development of infrastructure can offer new marketing opportunities. A farm will also be influenced by whether there are “wild” ecosystems close by. From there, they can access different resources for their cropping systems, such as planting Go to R3 to find the photo

gallery to help stimulate discussion about different cropping issues.

Figure 14: A landscape is composed of a mosaic of

as parasitic organisms that affect farms in the vicinity. On the other hand, if there are industrial areas around the farm, including large-scale agro-ecosystems using modern technologies such as chemical pesticides or genetically modified crops (see Sub-sections 2.4.1 and 2.3.2) these can reduce the ability of neighbouring farms to maintain their (agro) biodiversity and sustainability.

Agro-ecosystems currently use about 40 percent of the Earth’s total land base and they continue to expand because of pressures to meet growing demand for food, fodder and fibre. Such expansion means that agriculture is taking land from other ecosystems and the management practices of farms greatly affect the sustainability of these ecosystems. Land-use developments over the last fifty years have changed ecosystems more rapidly than in any comparable period of time in human history (MEA, 2005). Biodiversity on and around farms has declined through the use of fewer crop varieties, greater specialisation, and the use of chemical pesticides. Globally more than 100 000 areas have some degree of protection to preserve wildlife and ecosystems, yet these contain significant amounts of land used for agriculture (ileia, 2004). At the same time, many more of these conservation areas are “islands in a sea of farms, pastures and production forests” that are managed in ways that threaten the long-term survival of species and ecosystems. For example, at least half of the world’s temperate, sub-tropical and tropical forest ecosystems are dominated by crop and pasture production.

A balance is needed so that farmers can gain meaningful livelihoods in ways that do not lead to a decline in biodiversity at the landscape level. Just as farmers can adapt their methods to nurture the sustainability of their cropping systems through increasing diversity in their farms, they can also make a contribution to protecting biodiversity in the wider landscape. Measures that they might adopt include ensuring that their practices do not cause widespread erosion, pollute water systems, or poison the wider environment through indiscriminate use of chemical inputs. Many people work in, and depend upon landscapes for their livelihoods, including small-scale farmers. This can create pressures and improving the sustainability of cropping systems might often involve adopting a “landscape approach.” This involves close collaboration between farmers, herders and other land users in order to agree on how to manage common resources. Section 3.2.1 will discuss these kinds of consultation processes further. The next sub-section, takes a close look at the example of interactions between agro-ecosystems and the forest ecosystem, to illustrate wider issues of sustainability.

2.2.1 Forest ecosystems and

small-scale cropping

Sub-section 1.4.2 describes how agroforestry systems that mix woody perennials and crops can improve the sustainable productivity of farming. These systems can vary from intercropping to using trees in hedges or woodlots. Forest ecosystems have long been important to farmers and other people living close to them: for hunting

What kinds of different land uses can be found in a typical rural landscape in your area? What different kinds of ecosystems can be found there? How do small-scale farmers interact with these ecosystems to enhance their cropping systems?

Figure 15: Forests offer many products and services to farmers

as well as firewood, medicines, fibres and construction materials. Forests can also provide a source of various kinds of plants and other genetic resources that contribute to farmers’ cropping systems.

Forests in the vicinity of farms provide other benefits to farmers’ cropping systems as well. At the local level, forest cover has different buffering effects that influence the landscape, modifying the local climate by providing shade and absorbing heat energy; during cold seasons, they can act as a windbreak, reducing wind chill. The barrier effect of forests also reduces losses from evaporation and reduces wind erosion. Forests also provide stability to sloping land through their root structure and by intercepting water, protecting the soil from the effects of sheet erosion. By regulating the flow of water, they reduce surface erosion, sedimentation and down-stream flooding and, by filtering water pollutants, forests also protect water resources.

On a global level, forests help to mitigate the effects of climate change. As explained in Module 2, an increased concentration of carbon dioxide in the atmosphere is considered to be one of the principle causes of climate change. Because of plants’ important role in photosynthesis, they are a key factor in the carbon cycle. Plants absorb carbon dioxide from the atmosphere, combining it with water, then “storing” the carbon in the form of vegetation and, in the case of trees, in wood. This is known as “carbon sequestration.” As about 20 percent of tree weight is made up of carbon, forests can sequester a great deal of it. In total, according to the FAO (2006), the world’s forests and forest soils currently store more than one trillion tonnes of carbon -- twice the amount found floating freely in the atmosphere.

Clearing forests, particularly through burning, releases a great deal of carbon into the atmosphere, thereby increasing the effects of climate change. Reducing deforestation (and burning) can play an important role in reducing CO₂ emissions into the atmosphere. In the same way encouraging forest growth (through agroforestry or plantations) can add to carbon sequestration. Box 4 provides some information about the state of forests in the world today and the extent to which they are currently being cleared. Logging and mining companies and large-scale agriculturists establishing ranches and plantations are the most serious threat to forests. But small-scale farmers are also part of the problem, as they continue to clear forests in search of new land, often due to population pressure. Farmers practising shifting cultivation in marginal areas of the humid tropics, such as those in Southeast Asia, are finding that they need to think of more sustainable ways to use forests as their shrinking land base can no longer maintain productivity. In semi-arid Niger and other countries in the Sahel region of Africa, millions of hectares have been reforested by small-scale farmers through a method called Farmer Managed Natural Regeneration (FMNR). It is clear that farmers need to be part of a wider approach to reduce deforestation and increase forest regrowth.

Figure 16: Forests help to mitigate the effects of climate change.

Go to R2.6 and discuss the article about using dom palm forest products in Eritrea, and two articles about communities in Indonesia and Niger finding more sustainable ways to use and regenerate forests.