A field experiment consists of conservation agriculture (CA) and conventional tillage (CT) practices were set up in two areas, Robit and Dangishta, in sub-humid Ethiopian highlands. Irrigation water use, soil moisture, and agronomic data were monitored, and laboratory testing was conducted for soil samples, which were collected from 0 to 40 cm depth before planting and after harvest during the study period of 2015–2017. Calculation of crop coefficient (Kc) revealed a significant decrease in Kc values under CA as compared to CT. The result depicted that CA with a drip irrigation system significantly (α = 0.05) reduced Kc values of crops as compared to CT. Specifically, 20% reductions were observed for onion, cabbage, and garlic under CA whereas 10% reductions were observed for pepper throughout the crop base period. Consequently, irrigation water measurement showed that about 18% to 28% of a significant irrigation water savings were observed for the range of vegetables under CA as compared to CT. On the other hand, the results of soil measurement showed the CA practice significantly (α = 0.05) increased soil moisture (4%, 7%, 8%, and 10% increment for onion, cabbage, garlic, pepper) than CT practice even if irrigation input was small in CA practice. In addition, CA was found to improve the soil physico-chemical properties with significant improvement on organic matter (10%), field capacity (4%), and total nitrogen (10%) in the Dangishta experimental site. CA with drip irrigation is evidenced to be an efficient water-saving technology while improving soil properties to support sustainable intensification in the region.

中文翻译：

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滴灌保护性农业对亚湿润埃塞俄比亚高地作物系数和土壤特性影响的试验评价

田间试验包括保护性农业 (CA) 和常规耕作 (CT) 实践，在两个地区，Robit 和 Dangishta，位于亚湿润的埃塞俄比亚高地。对灌溉用水、土壤水分和农艺数据进行了监测，并对 2015-2017 年研究期间种植前和收获后 0 至 40 厘米深度的土壤样品进行了实验室测试。作物系数 (Kc) 的计算表明，与 CT 相比，CA 下的 Kc 值显着降低。结果表明，与 CT 相比，带有滴灌系统的 CA 显着 (α = 0.05) 降低了作物的 Kc 值。具体而言，在 CA 下观察到洋葱、卷心菜和大蒜减少 20%，而在整个作物基期观察到胡椒减少 10%。最后，灌溉用水测量表明，与 CT 相比，CA 下的一系列蔬菜可观察到约 18% 至 28% 的显着灌溉用水节约。另一方面，土壤测量结果表明，CA 实践比 CT 实践显着（α = 0.05）增加了土壤水分（洋葱、卷心菜、大蒜、辣椒增加 4%、7%、8% 和 10%）甚至如果在 CA 实践中灌溉投入很小。此外，发现 CA 改善了土壤理化性质，显着改善了 Dangishta 试验场的有机质 (10%)、田间持水量 (4%) 和总氮 (10%)。事实证明，采用滴灌的 CA 是一种有效的节水技术，同时还能改善土壤特性，支持该地区的可持续集约化。