摘要
This review presentsthe methods used to assess soil, pore water and groundwater nutrient levels on farms and agricultural fields. The purpose of this catalog of methods is to provide a basis for evaluating the efficiency of measures for the control of water catchment areas. A Zone monitoring model (ZMM) which is a basis for appropriate monitoring schemes in view of risks for the groundwater coming from agricultural lands has been developed. Based on this scheme, various methods to monitor nitrate concentrations at different unit levels, from the farm to the soil zone and on to the groundwater are described. At farm level, nutrient balances are mandatory to identify the potentially remaining concentrations of nutrients in the soil. Nutrient balances are incorporated in the latest information and communication technology (ICT) and farm management information systems (FMIS).The methods at groundwater-level described here are groundwater sampling by means of a suction lance, soil sampling beneath the groundwater table, groundwater sampling using the direct-push method, sampling from observation wells, from multi-level observation wells and from production wells. These practices are the early-warning systems which canprevent the surface and/or underground drinking water from contaminating with unwanted chemicals.