1,720,963 research outputs found
A new Danish concept for hectare-scale groundwater N-retention:Optimization of catch crop application at field and catchment scale
No full textA new Danish concept for hectare-scale groundwater N-retention mapping:Presentation, implementation and validation of the concept
No full textEvolution of soil mineral nitrogen under different catch crops fertilized with pig slurry after harvest of winter cereals in the north of Belgium
No full textIn temperate humid climates, catch crops have been proven to be a useful tool in the abatement of soil erosion, nutrient leaching and soil organic carbon losses. In Flanders (northern Belgium), the environmental policy allows farmers to apply manure after harvest at a rate of 60 kg N ha-1, if they sow a catch crop before the 1st of September (on light textures) or 15th of October (on heavy clay). This will only remain possible if nitrate leaching losses are not larger than when no additional manure is applied. To this end, field experiments were set up on 4 locations with different soil textures. Winter cereals were followed by 4 different catch crops: white mustard (Sinapsis alba), Italian ryegrass (Lolium multiflorum), black oat (Avena strigosa) and a grass-clover mixture (Lolium perenne, Trifolium repens, Trifolium pratense), sown at 2 different dates, 2-4 weeks apart. Before sowing, pig slurry was applied in 2 rates, corresponding to about 60 and 120 kg N ha-1 (60N, 120N), and a control without manure application was included (0N). Weather conditions were exceptionally favorable for catch crop growth. Soil mineral nitrogen content in the 0-90 cm layer (Nmin) was monitored during autumn 2011, winter and early spring 2012. From October to January, Nmin was significantly larger (p < 0.05) on the fallow plots compared to the plots with early sown catch crops for all cases; this was not always the case for late sown catch crops: in particular Italian ryegrass and the grass-clover mixture had relatively high Nmin contents. The effect of manure application depended strongly on sowing date too: under early sown catch crops Nmin showed no significant differences between 0N, 60N and 120N, with the exception of 1 single case. For late sown catch crops, Nmin was in some cases significantly different between 0N and 120N treatments, but never for white mustard. In early spring, Nmin was only significantly different between the fallow plots and the plots with frost resistant catch crops (Italian ryegrass and grass-clover mixture). In conclusion, an additional manure application of 60 kg N ha-1 after harvest of winter cereals did not significantly increase Nmin under catch crops, allowing the assumption that it neither increased nitrate leaching losses
Mitigating pesticide levels in surface waters : long-term surface water monitoring in an agricultural catchment
No full textLand Use and Water Quality
Full text linkThis collection of 11 papers introduces broad topics covering various professional disciplines related to the research arena of land use and water quality. The papers exemplify the important links between agriculture and water quality in surface and ground waters as well as the pollution problems around urban areas. Advancement of new technologies for analyzing links between land use and water quality problems as well as insights into new tools for analyzing large monitoring datasets are highlighted in this collection of papers
Dynamics of faecal pollution indicators in surface water draining an agricultural catchment
No full textAn integrated impact assessment of climate change, land use, and adaptation policies on water resources in Austria
No full textAssessment of cost-effectiveness of measures to reduce N and P emissions to Surface waters in Upper Austria - A catchment scale approach
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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