Based on Dixi district, the study of crop yields and precipitation, crop yields and soil fertility and soil fertility effects has been mabe.
本文以定西地区为例，对作物生产与自然降水、作物生产与土壤肥力以及土肥生产效应等方面进行了研究。
2
Using Ulrich's Periodicals Directory, Michael Mabe shows that the number of "refereed academic/scholarly" publications grows at a rate of 3.26 percent per year (i.e., doubles about every 20 years).