Tillage erosion affects crop yields and carbon balance in hummocky landscapes

可耕地土壤侵蚀是影响各种土壤相关生态系统服务的主要环境威胁。传统上研究的是水（部分是风）侵蚀，而农业土壤管理造成的侵蚀（耕作侵蚀）往往被忽视。然而，耕作侵蚀往往具有与水蚀相似的程度，在侵蚀性降雨较少的地区甚至可能是主要过程。该项目的主要目标是量化耕作侵蚀对作物产量和对德国东北部丘陵地貌碳循环反馈的影响。据推测，耕作侵蚀增加了田间产量变异性，降低了平均产量，但增加了景观土壤碳储量。试验区（Quillow集水区）的特点是机械化程度高，农业集约化程度高，降水量小，经常出现干旱。因此，农业生产对年际气候变化非常敏感。结合PI进行的一些初步区域研究和长期数据集（ZALF）的可用性，该区域非常适合这项研究。该工作方案结合了（一）实验方法，以确定侵蚀速率和碳平衡的组成部分，（二）多时相遥感作物产量的田间变异性，（三）和耦合土壤侵蚀和碳平衡建模（1960 - 2020年）。该项目将填补一个重要的差距，我们的理解之间的相互作用的耕作侵蚀，作物产量和碳循环在一个有代表性的丘陵景观，水侵蚀是小，但浅的土壤是特别敏感的侵蚀过程。德国东北部的试验区是一个重要的作物生产区，特别是在干燥的夏季，已经受到缺水的影响，这在侵蚀的山顶上最为明显。因此，这些地区非常适合作为世界上许多其他丘陵地区的展示，在这些地区，密集机械化农业导致明显的耕作侵蚀。

Soil erosion on arable land is a major environmental threat affecting various soil related ecosystem services. Traditionally water (and partly wind) erosion is studied, while erosion due to agricultural soil management (tillage erosion) is often ignored. Nevertheless, tillage erosion often has a similar magnitude as water erosion and can be even the dominate process in areas where erosive rainfall is rarer. The main goal of the project is to quantify the impacts of tillage erosion upon crop yields and upon feedbacks on the carbon cycle in a hummocky landscape in North-eastern Germany. It is hypothesized that tillage erosion increases in-field yield variability and decreases mean yields, but increase landscape soil carbon storage. The test region (Quillow catchment) is characterized by a strongly mechanized, intensive agriculture as well as small precipitation sums with regular dry spells. Agricultural production is, hence, very sensitive to interannual climate variability. In combination with a number of preliminary regional studies carried out by the PIs and the availability of long-term data-sets (ZALF) the region is ideally suited for this study. The working program combines (i) experimental approaches to determine erosion rates and C balance components, (ii) multi-temporal remote sensing of in-field variability of crop yields, (iii) and coupled soil erosion and C balance modelling (1960-2020). The project will close an important gap in our understanding of the interactions between tillage erosion, crop yields and carbon cycling in a representative hummocky landscape, where water erosion is small but shallow soils are especially sensitive to erosion processes. The test region in NE Germany is an important area of crop production which already suffers, especially in dry summers, from water shortage, which is most pronounce on eroded hilltops. Hence, the regions is ideally suited as showcase for many other hummocky regions of the world where intensively mechanized agriculture leads to pronounced tillage erosion.