A nitrate vulnerable zone (NVZ) is a conservation designation of the Environment Agency for areas of land that drain into nitrate polluted waters, or waterways which could become polluted by nitrates. A nitrate vulnerable zone can be designated as a response to an increase in nitrate leaching or increased use of nitrate rich fertilizers in a given area. Nitrate vulnerable zones were introduced by the United Kingdom government in response to the European Union (EU) mandate that all countries apart of the EU must reduce the nitrate in drinking water to a maximum of 50 mg/L because they affect public health and environmental health.

Causes edit

Nitrate vulnerable zones are designated when the concentration of nitrate in a given area reaches or surpasses 50 NO3- mg/L. One of the primary causes of nitrate pollution is the use of nitrogen fertilizers[1]. Nitrate fertilizers are stimulate crop production, but contribute to nitrate pollution of soil. Nitrate is released when the soil is disrupted by ploughing and when leaching occurs. Nitrate pollution can also come from precipitation and from manure.

Location edit

 
Farm in Europe.

In agricultural regions, NVZs cover 600,000 hectares, covering surface and ground water areas[1]. There are at least 70 NVZs in England as well as some NVZs in Wales.[1] Belgium, Germany, the Netherlands, and Denmark have established their entire nations as NVZs . These countries take a broader approach to designating nation-wide NVZs because of the quality of the groundwater[2] as well as marine eutrophication[1]. In contrast, the United Kingdom targets NVZs more specifically, identifying them as discrete zones in specific areas, allowing for the government to have more control over these areas.

Regulation Standards edit

The NVZs cover large areas of land that have been identified as exceeding or being at risk of exceeding 50 mg NO3-/L. NVZs have fairly relaxed rules on fertilizer application involving not fertilizing at certain times of the year (during the winter when runoff is greatest and uptake by plants at a minimum), reducing the amount of fertilizer used, and changing the times when animal waste is applied to the land (waste must be held in tanks over the period when it cannot be applied). Farmers who do not adhere to these restrictions can be fined by the government. The restrictions are within the guidelines of GAP (Good Agricultural Practice) meaning that farmers are expected to adhere to the given regulations without receiving any subsidies[3].

These NVZs are part of the scheme involved in NSAs (nitrate sensitive areas) which are assigned on a farm-scale basis and have much more stringent rules on nitrate application, including compensation for profits lost from following the rules.

Effects edit

Health edit

High levels of nitrate in drinking water used to prepare infant formula can affect infant health. With continued use of the contaminated water, infants can develop Blue Baby Syndrome where their skin will begin to appear blue-gray in color. Infants can become ill from this condition and it is fatal in some cases. Infants are affected by as low as 22.9 mg NO3-/L in drinking water [4]

References edit

  1. ^ a b c d Osborn, Suzie; Cook, Hadrian F. (1997). "Nitrate Vulnerable Zones and Nitrate Sensitive Areas: A Policy and Technical Analysis of Groundwater Source Protection in England and Wales". Journal of Environmental Planning and Management. 40 (2): 217–234. doi:10.1080/09640569712191. ISSN 0964-0568.
  2. ^ Arauzo, Mercedes (2017). "Vulnerability of groundwater resources to nitrate pollution: A simple and effective procedure for delimiting Nitrate Vulnerable Zones". Science of The Total Environment. 575: 799–812. doi:10.1016/j.scitotenv.2016.09.139. ISSN 0048-9697.
  3. ^ "Encouraging low-input farming in the EU". European Commission - European Commission. Retrieved 2021-04-03.
  4. ^ Knobeloch, L.; Salna, B.; Hogan, A.; Postle, J.; Anderson, H. (2000). "Blue babies and nitrate-contaminated well water". Environmental Health Perspectives. 108 (7): 675–678. doi:10.1289/ehp.00108675. ISSN 0091-6765. PMC 1638204. PMID 10903623.