Modeling the contribution of ephemeral gully erosion under different soil managements: A case study in an olive orchard microcatchment using the AnnAGNPS model
Modeling the contribution of ephemeral gully erosion under different soil managements: A case study in an olive orchard microcatchment using the AnnAGNPS model
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DOI：
10.1016/j.catena.2012.06.002
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发表时间：
2012-11
期刊：
影响因子：
6.2
通讯作者：
E. Taguas;Yongping Yuan;R. Bingner;J. A. Gomez
中科院分区：
文献类型：
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作者：
E. Taguas;Yongping Yuan;R. Bingner;J. A. Gomez
根据6.1hm2橄榄作物微集水区的试验结果，研究了不同土壤管理策略对环境和经济的影响，包括有沟和不有沟的自然草覆盖(SC/SCGC)和有和不有沟的常规耕作(T/TGC)。最初，在当前管理(SCGC)下记录的2a降雨-径流-泥沙负荷数据系列(34个事件)被用于在事件和月尺度上校准AnnAGNPS模型，提供对径流、峰值流量和泥沙负荷的适当调整(E>；70，r>；0.85)。还使用航空正射摄影术和野外工作确定了短暂的沟壑。在文献回顾的基础上，利用AnnAGNPS模型中用于模拟短暂沟谷形成和耕作作业的模块，对不同情景进行了比较，并进行了10年分析。平均输沙量分别为2.0t∗ha−1∗Year−1(SCGC)、3.5t∗ha−1∗Year−1(SC)、3.3t∗ha−1∗Year−1(TGC)和4t∗ha−1∗Year−1(T)。为了优化每种情况所需的环境和经济努力，评估了SC和T之间在泥沙来源(细沟/细沟间侵蚀和短暂沟壑)方面的显著差异(沟谷贡献的46%)和沟谷贡献的19%。最后，估算了与土壤流失有关的年度成本(1欧元∗ha−1∗Year−1)。SC是土壤管理中最有利可图的选择。尽管SCGC方法可进一步减少土壤流失，但其实施成本较高，对中期产量损失的影响较小，这表明如果没有额外的支持(例如对沟渠治理措施的补贴)，农民就不会有明显的动机使用该方法。
A study was undertaken into the environmental and economic impacts of different soil management strategies, spontaneous grass cover with and without gully control (SC/SCGC) or conventional tillage with and without gully control (T/TGC), based on the experimental results obtained in an 6.1ha olive crop microcatchment. Initially, 2years of rainfall–runoff–sediment load data series, (34 events) recorded under the current management (SCGC), was used for the calibration of the AnnAGNPS model at event and monthly scales providing suitable adjustments of runoff, peak flow and sediment loads (E>70, r>0.85). Ephemeral gullies were also identified using aerial orthophotography and field work. The module of the AnnAGNPS model for simulating ephemeral gully generation and the tillage operations based on a bibliographical review were used to compare different scenarios and to perform a 10year-analysis. The results showed mean runoff coefficients of 10.0% for SC/SCGC and of 3.2% for T/TGC while the average sediment loads were 2.0t∗ha−1∗year−1(SCGC), 3.5t∗ha−1∗year−1(SC), 3.3t∗ha−1∗year−1(TGC) and 4t∗ha−1∗year−1(T). Significant differences in sediment sources (rill/inter-rill erosion and ephemeral gullies) were evaluated between SC (46% of gully contribution) and T (19% of gully contribution), in order to optimize the environmental and economic effort required in each case. Finally, the annual costs associated with soil losses were estimated (<1€∗ha−1∗year−1). SC was the most profitable alternative for soil management. Despite the additional reduction in soil losses of the SCGC approach, the higher cost of its implementation and the minor effect on yield losses in the medium term suggest that without additional support (such as subsidies for gully control measures), farmers would have not an obvious incentive to use it.