WASCAL Program on Climate Change and Land Use, Department of Civil Engineering, KNUST, Kumasi, Ghana; Laboratory of Botany & Plant Ecology, University of Lomé, 01 PO Box: 1515 Lomé, Togo.
International Centre for Agricultural Research in Dry Areas (ICARDA), P.O. Box 950764, Amman 11195, Jordan; Program Management Unit (PMU), CGIAR Research Program on Dryland Systems(CRP-DS), c/o ICARDA, P.O. Box 950764, Amman 11195, Jordan.
Sci Total Environ. 2018 Jun 1;625:1309-1320. doi: 10.1016/j.scitotenv.2017.12.228. Epub 2018 Jan 12.
The rural landscapes in Central Togo are experiencing severe land degradation, including soil erosion. However, spatially distributed information has scarcely been produced to identify the effects of landscape pattern dynamics on ecosystem services, especially the soil erosion control. In addition, relevant information for sustainable land and soil conservation is still lacking at watershed level. On this basis, using the LAndscape Management and Planning Tool for the Mo River basin (LAMPT_Mo), we (1) modelled soil erosion patterns in relation with land use/cover change (LUCC), land protection regime, and landforms, and (2) examined the efficiency of landscape redesign options on soil erosion amounts at basin scale. We found that Simulated historical net soil loss (NSL) for the Mo basin were approximately 26, 23, 27, and 44t/ha/yr, for 1972, 1987, 2000, and 2014, respectively. These simulated NSLs were higher than the tolerable soil loss limits for the Tropics. Steep slopes (≥15°), poorly covered lands (croplands and savannas), and riversides (distances ≤100m) are critical areas of sediment sources. The local appraisal of soil loss was in line with the simulated outputs even though quantification was not accounted for when dealing with rural illiterate people. Furthermore, results showed that the examined management measures, such as controlling the identified erosion hotspots through land protective measures, could help reduce the NSL up to 70%, to values closer to the tolerable limits for the Tropics. The model implementation in the basin showed insights for identifying erosion hotspots and targeting soil conservation planning and landscape restoration measures.
多哥中部的乡村景观正经历着严重的土地退化，包括土壤侵蚀。然而，几乎没有产生空间分布信息来识别景观格局动态对生态系统服务的影响，特别是对土壤侵蚀的控制。此外，在流域层面上，仍然缺乏有关可持续土地和土壤保护的相关信息。在此基础上，我们使用莫罗河流域景观管理和规划工具（LAMPT_Mo）：（1）模拟了与土地利用/覆被变化（LUCC）、土地保护制度和地形有关的土壤侵蚀模式；（2）检验了流域尺度上景观重新设计方案对土壤侵蚀量的效率。我们发现，莫罗河流域模拟的历史净土壤流失（NSL）分别约为 1972 年、1987 年、2000 年和 2014 年的 26、23、27 和 44t/ha/yr。这些模拟的 NSL 高于热带地区可容忍的土壤流失限值。陡坡（≥15°）、植被覆盖不良的土地（耕地和热带稀树草原）和河流两岸（距离≤100m）是泥沙源的关键区域。尽管在处理农村文盲问题时没有考虑量化，但当地对土壤流失的评估与模拟结果一致。此外，结果表明，所检查的管理措施，如通过土地保护措施控制已确定的侵蚀热点，可以帮助将 NSL 减少多达 70%，使其更接近热带地区可容忍的限值。该模型在流域中的实施为识别侵蚀热点以及针对土壤保护规划和景观恢复措施提供了思路。
