Evaluation of Fall Residual Nitrogen Influenced by Soil Chemical Characteristics and Crop History in Flanders (Belgium)

Abstract

In the framework of the "Directive concerning the protection of waters against pollution caused by nitrate from agricultural resources (91/676/EEC)," losses of nitrate nitrogen to groundwater and surface water have to be limited. In the moderate climate regions of western Europe, drainage losses mainly occur during wintertime. The residual nitrate nitrogen in the soil profile after the harvest in autumn is considered as the main determinant of nitrate losses. In Flanders, a preliminary limit value of 90 kg NO 3 -N ha 21 up to a soil depth of 0.90 m between 1 October and 15 November is proposed. During this period in 2001, the Soil Service of Belgium sampled .18,000 fields. From these results, some interesting conclusions can be drawn. As expected, differences in residual nitrate after harvest are highly influenced by the crop, soil type, and carbon content of the soil. The percentage of fields with a residual nitrate nitrogen content below the target value of 90 kg N ha 21 differed from 39% to 86%, because of the influence of the crop grown on the parcel. On an average, a high nitrate value was found after early harvested crops (cereals, flax [Linum L.]) and after crops with high protein content due to plant residues remaining on the field after harvest (peas [Pisum sativum L.] and beans [Phaseolus vulgaris L.]). Soil type was also important because, only 42% of the fields with clay soils were below 90 kg NO 3 -N ha 21 , and in sandy soils this figure was 75%. This is

The regularities of mineral nitrogen distribution in Lithuania’s soils in spring

“…The data obtained from this long-term monitoring enabled us to identify the most important factors affecting the levels of soil N min concentration in spring and to summarize the effect of peculiar characteristics of different zones of Lithuania on the N min concentration in soil. The determined regularities in the influence of crops and pre-crops, soil texture, precipitation and average air temperature during winter period on the soil N min concentration correspond largely to the results obtained in other countries (Beaudoin et al, 2005;Geypens et al, 2005;Liu et al, 2005;Tong et al, 2005;Wiesler, Armbruster, 2009;Rutkowska, Fotyma, 2011). The obtained results of soil N min tests conducted in spring taking into account the detailed division of Lithuania's territory into 15 soil regions, differing in landscape, climatic conditions, soil type and texture, enabled the assessment of the long-term changes in N min concentration on the level of specific location considering its conditions.…”

Distribution of Mineral Nitrogen in Soil in Relation to Risk of Nitrate Leaching in Farms with Irrigated Vegetables and Early Potatoes

“…Average simulated amount of leached N reached maximum of 15 kg N·ha -1 from 0-30 cm zone in 2015. The comparison of leaching data from literature is not feasible considering the vast range of production, soil and weather conditions (Geypens et al 2005); however, the authors agree that vegetables and potatoes pose increased risk of nitrate leaching (e.g., Neeteson & Carton 2001, Francis et al 2003. The nitrate shifting from top to shallow subsoil may be extracted by subsequent crops.…”

“…The leaching of nitrates is governed by water percolating from the saturated top layers rich in mineral and organic materials. A simplified approach is satisfactory for the period between late autumn and early spring with low evapotranspiration; therefore, residual Nmin or nitrate contents before winter are widely used as an indicator of leaching potential (Geypens et al 2005). In short, effective ____________________________________________________________________________________________________________________ precipitation, soil nitrate and water contents, as well as their distribution at the onset of winter are the main inputs for the estimation of nitrate leaching during this period (Burns 1976;Buczko et al 2010).…”

“…The region also falls under delimited vulnerable zones, the measures have just recently included the limits on nitrogen rates for vegetables that might be controlled and sanctioned. Evidently, a set of best management practices must be introduced to minimize nitrate leaching (Hartz 2006;Geypens et al 2005;DEFRA 2010). To harmonize the goals of both growers and the requirements for water quality, more data on the behaviour of nitrogen in the specific crop system is needed.…”

Mapping wetland loss and restoration potential in Flanders (Belgium): an ecosystem service perspective.

“…Important variables are the specific combinations of soil texture, crop type, agricultural fertilizer application (kg N/ha) and atmospheric N-deposition (kg N/ha). Long-term data on autumn and spring nitrate residues in agricultural soils were available from the Flemish Land Agency (Geypens et al 2005). The difference between fall and spring residue is assumed to be leached out by winter precipitation.…”