Nutrient balances in agriculture: A basis for the efficiency survey of agricultural groundwater conservation measures

Abstract

In nutrient balances, additions and removals of nutrients are assessed to identify the remaining concentrations of nutrients in soil. Balances can be performed using operational records of nutrients applications and other agronomic information (crops, yields, weather, etc.) at farm or even field level. The aim of performing nutrient balances is to obtain an overview of nutrient levels, in particular to prevent surpluses that could lead to environmental problems such as groundwater contamination, water eutrophication, air pollution and an increase in greenhouse gas emissions. This chapter will provide an overview of methods used to assess soil nutrient levels at farm and field level. The methods described here can be used by farmers, landscape planners, environmentalists, politicians and other stakeholders as a basis for taking agricultural groundwater conservation measures. The procedures and recommendations specified in this chapter are in accordance with the guidelines of the DWA—German association for water, wastewater and waste: ‘‘Efficiency of measures to control land use for groundwater conservation—the example of nitrogen’’ (DWA-M 911 (2013): Effizienzkontrolle von Maßnahmen zur grundwasserschonenden Bodennutzung am Beispiel des Stickstoffs).