当前位置: X-MOL 学术Catena › 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.)
A GIS-based assessment of the potential soil erosion and flood hazard zones in Ekiti State, Southwestern Nigeria using integrated RUSLE and HAND models
Catena ( IF 6.2 ) Pub Date : 2020-06-06 , DOI: 10.1016/j.catena.2020.104725
Idowu Ezekiel Olorunfemi , Akinola Adesuji Komolafe , Johnson Toyin Fasinmirin , Ayorinde Akinlabi Olufayo , Samuel Olumide Akande

Soil loss estimation and flood hazard mapping cannot be overemphasized due to their environmental, economic and societal concern. Thus, the main objective of this study was to assess the potential soil erosion and flood hazards zones using Revised Universal Soil Loss Equation (RUSLE) and Hand Above Nearest Drainage (HAND) models, respectively for appropriate conservation and prevention measures in Ekiti State, Southwestern Nigeria. The result reveals annual soil erosion ranges from 0 to 889 t ha−1 year−1. The estimated total annual soil loss in the state was around 1.5 million tonnes, of this, 193223.3 tonnes which covers 7508 ha was lost at a rate much greater than the tolerable soil loss rate. Soil erosion vulnerability mapping was done using six (6) categories of soil loss severity from slight to very severe. Soil erosion rates varied from 0.21 t ha−1 year−1 in forests to 1.69 t ha−1 year−1 under bare soils. The very steep slope category had the highest soil erosion rate of 15.07 t ha−1 year−1 while the gentle slope regions had the least soil erosion rate of 0.39 t ha−1 year−1. About 23% of the area which covers 115847.58 ha was prone to high flood hazard whereas 15.69% (80932.30 ha) was moderately susceptible to flood risk. Approximately 15% of the area was susceptible to low flood hazard zone while 44.90% were vulnerable to very low flood occurrence. LULC has significant effect on the spatial pattern of soil loss in the study area. Potential soil loss risk zones were highly related to the degree and inclination of slope. The reported results can serve as preliminary information to determine erosion and flood hotspots in the study area and as input for policy decision for disasters prevention and conservation measures.



中文翻译:

基于GIS的RUSLE和HAND模型对尼日利亚西南部Ekiti州潜在的水土流失和洪灾危险区进行了评估

由于其对环境,经济和社会的关注,不能过分强调土壤流失估计和洪水灾害图。因此,本研究的主要目的是分别使用修订后的通用土壤流失方程(RUSLE)和“高于最近的排水量”(HAND)模型评估潜在的土壤侵蚀和洪水危害区域,以在西南埃基蒂州采取适当的保护和预防措施。尼日利亚。结果表明,每年的土壤侵蚀范围为0到889 t ha - 1-1。该州每年估计的总土壤流失量约为150万吨,其中19322.23吨(占地7508公顷)流失的速度大大超过了可容忍的土壤流失速度。使用六(6)类土壤流失严重性(从轻度到非常严重)进行了土壤侵蚀脆弱性制图。土壤侵蚀率从森林中的0.21 t ha - 1-1到裸土下的1.69 t ha - 1-1都不等。陡坡地区的土壤侵蚀速率最高,为15.07 t ha - 1-1,而坡缓地区的土壤侵蚀速率最低,为0.39 t ha - 1-1。占地115847.58公顷的地区中约23%容易遭受高洪灾危害,而15.69%(80932.30公顷)中度易受洪灾风险的影响。大约15%的地区易受低洪灾危险区的影响,而44.90%的地区易受极低洪灾的影响。LULC对研究区土壤流失的空间格局有重要影响。潜在的土壤流失危险区与坡度和坡度高度相关。报告的结果可作为确定研究区水土流失和洪灾热点的初步信息,也可作为防灾和保护措施政策决策的依据。

更新日期:2020-06-06
down
wechat
bug