Soil Erosion and Degradation Research Group, Department of Geography, Valencia University, Blasco Ibàñez, 28, 46010, Valencia, Spain.
School of Agriculture, Hellenic Mediterranean University, 71410, Heraklion, Greece.
J Environ Manage. 2021 Mar 15;282:111965. doi: 10.1016/j.jenvman.2021.111965. Epub 2021 Jan 16.
Early season fruit production for the northern European market is highly intensive in fertilization, machinery, irrigation and the use of herbicides. Those conditions increase the soil losses and soil compaction and threaten the Sustainable Goals for Development of the United Nations by 2030. Long-term soil erosion measurements are necessary to determine the sustainability of agriculture managements. Moreover, soil erosion on flood irrigation land is a topic that request more surveys and research as rainfed sloping terrains attracted all the attention of scientists and research investment. Improved Stock Unearthing Method (ISUM) was applied to two 15 years-old herbicide treated fields of Saturn peaches (Prunus persica var. platycarpa) to determine long-term soil erosion rates (2004-2019). Using ISUM, a 1 mm thick nylon rope (700 mm length) was used to connect trees perpendicular to the direction of rows at the height of the graft. To detection soil lowering, the vertical distance of the rope to the soil surface was measured at 10 cm intervals along the rope. The ring method (264 samples at 0-6 cm) was used to determine the soil bulk density, which was in average 1.15 gr cm for both plots. There was found a compaction in the centre of both plots due to the pass of machinery with mean bulk density values of 1.23 gr cm, meanwhile underneath of the trees, the soil bulk density was 1.05 gr cm. The topography survey carried out with ISUM (2508 sampling points) informed that flood irrigation redistributed the soil from the upper to the lower field position, where a sedimentation layer was measured. We found that the two studied fields showed a contrasted response, with low soil erosion values in Benimodo and high in L'Alcúdia study sites. Soil erosion rates were in average 1.46 Mg ha yr and 8.02 Mg ha yr for Benimodo and L'Alcúdia, respectively. However, the maps development using ISUM allow to inform that the pattern of soil redistribution is similar for both fields as the highest soil lowering was found in the upper field part, where the flood discharge detach soil particles. In the lower field position sedimentation takes place. The dataset allows us to conclude that soil erosion in Saturn peaches fields is non-sustainable and more soil conservation management should be applied to reduce the soil erosion rates due to the bare soils as a consequence of the use of herbicides. This research informs that soil erosion in flood irrigated fields is a relevant process that needs more investigations around the world, where 94% of the irrigated land is under flood or furrow irrigation, and where irrigation is growing year after year.
北欧市场的早春水果生产在施肥、机械、灌溉和除草剂的使用方面非常密集。这些条件增加了土壤流失和土壤压实的风险，威胁到 2030 年联合国可持续发展目标。长期的土壤侵蚀测量对于确定农业管理的可持续性是必要的。此外，洪水灌溉土地上的土壤侵蚀是一个需要更多调查和研究的课题，因为雨养坡地吸引了科学家的全部注意力和研究投资。改良的露头挖掘法（ISUM）被应用于两个 15 岁的受除草剂处理的 Saturn 桃（Prunus persica var. platycarpa）田，以确定长期的土壤侵蚀率（2004-2019）。使用 ISUM，一根 1 毫米厚的尼龙绳（700 毫米长）被用来将树木垂直连接到接枝高度的行的方向上。为了检测土壤下降，沿着绳子每隔 10 厘米测量绳子到土壤表面的垂直距离。环法（0-6cm 处有 264 个样本）用于确定土壤容重，两个地块的平均容重为 1.15 克/立方厘米。由于机械的通过，两个地块的中心都出现了压实现象，平均容重值为 1.23 克/立方厘米，而树木下方的土壤容重为 1.05 克/立方厘米。利用 ISUM 进行的地形测量（2508 个采样点）表明，洪水灌溉将土壤从上部位置重新分配到下部位置，在那里测量到了一个沉积层。我们发现，两个研究地块表现出截然不同的反应，Benimodo 地块的土壤侵蚀值较低，而 L'Alcúdia 地块的土壤侵蚀值较高。Benimodo 和 L'Alcúdia 的土壤侵蚀率分别为平均 1.46 Mg/公顷年和 8.02 Mg/公顷年。然而，使用 ISUM 开发的地图表明，两个地块的土壤再分配模式相似，因为最高的土壤下降发生在洪水排放分离土壤颗粒的上部地块。在下部地块位置，发生了沉降。该数据集使我们能够得出结论，Saturn 桃田的土壤侵蚀是不可持续的，由于除草剂的使用导致裸土，应采用更多的土壤保持管理措施来降低土壤侵蚀率。这项研究表明，洪水灌溉土地的土壤侵蚀是一个相关的过程，需要在全球范围内进行更多的调查，全球 94%的灌溉土地采用洪水灌溉或沟灌，而且灌溉面积逐年增加。
