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在水土保持及其管理项目中,需要准确评价土壤侵蚀对作物产量的影响。气候的变化导致侵蚀和未侵蚀土壤的玉米产量有一定的变化幅度,并呈现长期的趋势。将中北部地区典型土壤的短期玉米产量数据与NTRM模型计算的产量数据结合起来,研究旱作小区的历史气候对相应的玉米产量的长期影响。结果表明,与对照相比,强度侵蚀土壤的玉米产量多年平均降低10%,在冰碛物上发育的土壤降低12%,黄土母质发育的土壤降低7%。用NTRM模型统计结果表明,土壤物理性质的变化,特别是土壤有效持水量的变化时玉米产量有极大的影响。玉米生长季平均降雨量,短期研究中为35.3cm,长期研究中为36.3cm,故而导致强度侵蚀土壤的玉米产量短期内降低9%,长期内降低10%。
In soil and water conservation and its management projects, the impact of soil erosion on crop yield needs to be accurately evaluated. Changes in climate have led to some variation in maize production in eroded and unetched soils, and have shown a long-term trend. Short-term maize yield data from typical soils in central and northern China were combined with yield data from the NTRM model to study the long-term effects of historical climate on corresponding maize yields in dry farming communities. The results showed that, compared with the control, the maize yield in intensively eroded soils dropped by an average of 10% for many years, 12% for soils developed on moraines and 7% for loess parental development. The results of the NTRM model show that the change of the physical properties of the soil, especially the change of the effective soil water holding capacity, has a great impact on the yield of corn. The average maize growing season rainfall was 35.3 cm in the short-term study and 36.3 cm in the long-term study, resulting in a 9% reduction in short-term maize yield and a 10% reduction in the long run.