中文摘要：

以黄河三角洲地区东营市暗管排水项目为例,进行了工程财务评价、应用效果调查,分析了该项目的经济、生态和社会效益。结果表明：安装暗管排水系统之后,研究区盐碱化荒地全部得到改造并增加耕地297.63hm2,新增耕地占总土地面积44.6%,土壤脱盐率达90%以上。项目财务评价发现：研究区种植棉花的财务净现值为809.93万元（折现率为12%）,动态投资回收期为7.54 a,财务内部收益率为21.97%,大于基准收益率（12%）。结果表明暗管排水在黄河三角洲地区具有良好的应用前景。

英文摘要：

Taking the subsurface drainage project in the Yellow River Delta as an example,we conducted financial analysis and investigation of the project performance;we analyzed the economic,ecological and social benefits.The results showed that 297.63 hm2 salinized wasteland was reclaimed into arable land,accounting for 44.6% of the total farmland area in the project area;more than 90% of the subsurface drained land have been desalinized.The subsurface drainage project produced remarkable economic,ecological and social benefits.For cotton production in the study area,the calculated financial net present value（FNPV） was 8099300 yuan for a discount rate of 12%,the dynamic investment pay-back period（PT） was 7.54 years;the Financial Interval Revenue Rate（FIRR） was 21.97%,which is greater than the benchmark yield of 12%.Therefore,it is beneficial to build subsurface drainage systems in the Yellow River Delta.