Farming intensity and biodiversity
Farming in Europe ranges from the most intensive production systems, typically on more fertile land, to very low-intensity, more traditional landuses, usually found on poorer land. The differences in intensity are enormous. Nitrogen inputs range from none to several hundred kg/ha/year, arable yields from less than 1 t/ha to over 10 t/ha, olive yields from less than 0.5 t/ha to over 8t/ha, and livestock densities from as low as 0.1 Livestock Units (LU) per hectare, to 5 LU or more.
Biodiversity usually is higher on farmland that is managed at a low intensity.
A more intensive application of machinery, fertilisers, biocides and livestock reduces the opportunities for wildlife on cropped and grazed land. At the same time, intensive use of farmland tends to eliminate features such as field margins and uncultivated patches.
At the lowest end of the intensity spectrum, the productive land itself supports a range of wildlife species, especially when it includes a high proportion of semi-natural1 pasture. Low-intensity farming of this sort covers extensive areas of Europe’s more marginal regions, and the future of many of our most valued habitats and species depends on these large areas continuing under such use. The term High Nature Value farming was coined to emphasise this crucial role of low-intensity farming in European biodiversity conservation (Baldock et al.,1993).
Low-intensity, HNV farming faces enormous challenges of socio-economic viability. As intensive farming expands and increases its yields, and as incomes rise in the wider economy, it becomes harder to earn a living from HNV farming. Across vast areas of the EU’s most fragile rural landscapes, HNV farming faces stark choices between abandonment and intensification. Every day, farmers are giving up and selling their stock. Landscapes rich in biodiversity and culture, beneficial for soil conservation and climate change, and resistant to forest fires, are being lost to scrub, dense forest or new intensive uses, such as irrigated cropping.
1 Semi-natural vegetation is naturally occuring (not planted) grass, scrub or woodland that is grazed and/or cut on a regular basis, resulting in a state that mimics natural habitats. See section below for more details.
