Nitrogen: Massive nitrogen surpluses occur in particular in regions where intensive livestock farming is common. Nitrogen enters groundwater, lakes and rivers through slurry in the form of nitrate, has a eutrophying effect and generates costs in drinking water production. Ammonia and nitrous oxide off-gases from nitrogen into the air, with a number of consequences: firstly, soil acidification and loss of biodiversity, and secondly, nitrous oxide drives climate change and is more damaging than CO2
. Although nitrogen inputs from agriculture have declined – from 118 kg per hectare in 1993 to 97 kg per hectare in 2013, the rate of decline has slowed significantly over the past decade, leaving Germany far from achieving its own goal of reducing nitrogen surplus to 70 kg per hectare (five-year average of the years 2028 to 2032).
Plant protection products: The intensive application of pesticides on fields and land also has an impact on the environment. Numerous studies have demonstrated a correlation between plant protection products (PPP) and insect die-off. Even groundwater regularly reveals traces of PPP residues. An average 8.8 kg of PPP is applied to one hectare of agricultural land per year, with the equivalent of 2.8 kg of active ingredients. Sales of PPP are still on a high level with only small changes in the last 20 years. The herbicide group represents the largest share, including glyphosate. Their application must be reduced significantly in favour of non-chemical alternatives. Also, offsetting the harmful effects of herbicides requires more areas in the landscape on which no PPP are used, for example uncultivated land and blooming strips, to preserve the habitat and food resources of endangered bird and insect species.
Habitats and biodiversity: Birds and other wild animals need intact habitats. Agricultural activities consume the largest share of land in Germany, putting a particularly heavy strain on the environment. A clear negative trend can be observed among bird species like the skylark, lapwing or little owl which are typical on agricultural land: the indicator dropped to 57% in 2014 (target value for 2030: 100%). That figure was still 117% in 1975. The share of land with high nature value – species-rich grassland, fallow areas, meadow orchards – is on the decline. The indicator was still 13.1% in 2009 but fell to 11.4% in 2015. The area of permanent grassland in Germany shrank from 5.3 million hectares in 1991 to 4.7 million hectares in 2015. Nearly half of the species typical of grassland are threatened or have already vanished.