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Land use and soil
Land use and land management practices have a major impact on natural resources including water, soil, nutrients, plants and animals. Land use information can be used to develop solutions for natural resource management issues such as salinity and water quality. For instance, water bodies in a region that has been deforested or having erosion will have different water quality than those in areas that are forested.
Two of the biggest issues relating to land-use are:
Contamination
Soil contamination is the human-induced deposition of harmful substances which are not a product of natural accumulation or soil formation. Many human activities, ranging from mining activities, industrial and agricultural production to road transport, result in pollution that can accumulate in the soil or result in biological and chemical reactions in the soil.
Erosion
Soil erosion is the removal of soil by wind and water. This natural process is intensified by human activities, such as deforestation for agricultural purposes, changes in hydrological conditions, overgrazing and other inappropriate agricultural activities. Erosion can lead to soil degradation and eventually complete destruction.
Land use for agriculture
Agriculture uses soils and water as a resource for food production, and at the same time impacts on these resources. The extent and causes of the environmental impacts of agriculture, notably by farm and crop type, vary significantly. Nevertheless, the continuing search for efficiency, lower costs and increased scale of production is resulting in substantial pressures on the environment, landscapes and biodiversity, particularly in the most intensively farmed areas. At the same time, agriculture remains essential to the maintenance of many cultural landscapes.
Agricultural production throughout New Zealand continues to rely on non-farm resources such as inorganic fertilisers and pesticides. However, there has been a decline in the use of these resources and, particularly in eastern Europe, a reduction in the pressure on the environment.
Recent shifts to environmentally-friendly production systems are apparent, for example, organic production and conservation tillage systems. Organic farming covered about ??% of the total agricultural area of New Zealand. The development of certified organic farming in other European regions still lags significantly behind this figure.
In terms of resource conservation, the most important impacts of arable and livestock production are those relating to soil erosion and nutrient leaching, respectively. Soil erosion increases with the share of arable land of total land use, mitigated by physical background factors (slope, soil type, rainfall patterns) and farming practices.
Nutrient leaching is caused where the application of livestock manure and mineral fertilisers exceeds the nutrient demand of crops. The highest nutrient surpluses are found in areas of intensive livestock production, particularly in north-western Europe.
While agriculture can exert significant pressure on the environment, it is itself subject to negative environmental impacts linked to air pollution and urban development.
Soil sealing by transport or housing infrastructure also eliminates hundreds of hectares of agricultural land every year.
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