当前位置: X-MOL 学术Soil › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Soil nitrogen and water management by winter-killed catch crops
Soil ( IF 6.8 ) Pub Date : 2021-11-16 , DOI: 10.5194/soil-2021-124
Norman Gentsch , Diana Heuermann , Jens Boy , Steffen Schierding , Nicolaus von Wirén , Dörte Schweneker , Ulf Feuerstein , Georg Guggenberger

Abstract. Improving N cycling in agroecosystems is one of the key challenges in reducing the environmental footprint of agriculture. Further, uncertainty in precipitation makes crop water management relevant in regions where it has not been necessary thus far. Here, we focus on the potential of winter-killed catch crops to reduce N leaching losses from N mineralization over the winter and soil water management. We compared four single catch crops (white mustard, phacelia, Egyptian clover and bristle oat) and a fallow treatment with two catch crop mixtures with 4 and 12 plant species (Mix4 and Mix12). High-resolution soil mineral N (Nmin) monitoring in combination with modelling of spatiotemporal dynamics served to assess N cycling under winter-killed catch crops, while soil water was continuously monitored in the rooting zone. Catch crops depleted the residual Nmin pools by between 40 and 72 % compared to the fallow. The amount of residual N uptake was lowest for clover and not significantly different among the other catch crops. Catch crops that produce high N litter materials, such as clover and mustard leaves, showed an early N mineralization flush immediately after their termination and the highest leaching losses from litter mineralization over the winter. Except for clover, all catch crops showed Nmin values between 18 and 92 % higher on the sowing date of the following maize crop. However, only Mix12 was statistically significant. Catch crops depleted the soil water storage in the rooting zone during their growth in autumn and early winter, but preserved water later on when their residues cover the ground. The shallow incorporation of catch crop residues increased water storage capacity during the cropping season of the main crop even under drought conditions. Hence, catch cropping is not just a simple plant cover during the winter but improved the growth conditions for the following crop at decreased N losses. Mixtures have been shown to compensate for the weaknesses of individual catch crop species in terms of nutrient capture, mineralization and transfer to the following main crop as well as for soil water management. Detailed knowledge about plant performance during growth and litter mineralization patterns is necessary to make optimal use of their full potential.

中文翻译:

冬季捕杀作物对土壤氮和水的管理

摘要。改善农业生态系统中的氮循环是减少农业环境足迹的主要挑战之一。此外,降水的不确定性使作物水分管理在迄今为止没有必要的地区变得重要。在这里,我们关注冬季捕杀作物减少冬季氮矿化造成的氮浸出损失和土壤水分管理的潜力。我们比较了四种单一的捕获作物(白芥菜、紫花苜蓿、埃及三叶草和刚毛燕麦)和休耕处理的两种捕获作物混合物,分别有 4 种和 12 种植物物种(Mix4 和 Mix12)。高分辨率土壤矿物 N (N min) 监测与时空动力学模型相结合,用于评估冬季捕杀作物下的氮循环,同时在生根区持续监测土壤水分。与休耕相比,捕捞作物消耗了40% 到 72%的剩余 N min池。三叶草的残余氮吸收量最低,其他捕捞作物之间没有显着差异。生产高 N 凋落物材料的捕捞作物,如三叶草和芥菜叶,在其终止后立即显示出早期的 N 矿化冲洗,并且在整个冬季来自凋落物矿化的浸出损失最高。除三叶草外,所有捕捞作物均显示 N min在接下来的玉米作物的播种日期,值高出 18% 到 92%。然而,只有 Mix12 具有统计显着性。捕捞作物在秋季和初冬的生长过程中耗尽了生根区的土壤储水量,但稍后当其残留物覆盖地面时保留了水分。即使在干旱条件下,捕获作物残留物的浅掺入也增加了主要作物种植季节的蓄水能力。因此,捕捞作物不仅是冬季简单的植物覆盖,而且在减少氮损失的情况下改善了下一季作物的生长条件。混合物已被证明可以弥补个别捕捞作物物种在养分捕获、矿化和转移到后续主要作物以及土壤水分管理方面的弱点。
更新日期:2021-11-16
down
wechat
bug