摘要
分析了膜下滴灌应用典型灌区新疆石河子121团连续4年的定点监测膜下滴灌棉田盐分。结果表明,盐分在膜下滴灌灌水作用下不断向远离滴灌带的区域迁移,水平方向逐渐向膜间裸地聚集,垂直方向逐渐向下层运移。剖面盐分随滴灌应用年限的增加逐渐由上大下小变化为上下均一的垂线状,这个过程尤其在滴灌应用2~4年表现得比较明显。滴灌应用4年深层(140 cm土层)开始脱盐,滴灌应用5年基本达到作物适宜耐盐含量。盐分降低主要原因在于当地的灌溉制度。灌水特别是较大定额的灌水,改变了盐分自然分布特点。在周期性灌水作用下,各年生育期内盐分含量相对较低,土壤盐分总量呈降低趋势。盐分降低主要时期在出苗水灌后及花铃后期。随滴灌应用年限的增加,300 cm深度范围内土壤盐分也逐渐降低,滴灌应用约10年左右呈铅垂线改良型分布特点。现行膜下滴灌灌水制度在滴灌应用5年以上应适当减少花铃期的灌水定额,灌溉定额可降至618 mm左右,但苗期灌水仍需保持较大的灌水定额。
With the application of mulched drip irrigation, soil salt distribution and variation features in agricultural fields are catching attentions year by year. In the 121 Regiment of the Xinjiang Production and Construction Corps (XPCC), Shihezi City, Xinjiang which is a typical area with mulched drip irrigation, soil salts in cotton fields were monitored for 4 consecutive years. The results showed that soil salts were continuously transferred away from the irrigation lines by the irrigation water. Horizontally, the salts gradually accumulated towards the bare soil between films, while vertically, they moved gradually towards deeper layers. Soil salt distribution in soil profiles changed from a wineglass shape (which was typical in wasteland and narrows down towards deeper soil layers) to a uniform vertical line with longer history of mulched drip irrigation. And this change was relatively pronounced from the 2nd to the 4th year of irrigation. After 4 years of irrigation, the soil at 140 cm below surface began to be desalinized and after 5 years of irrigation soil salt content was at a point that crops could tolerate. Soil salt content decrease was mainly affected by the local irrigation regime. Irrigation, especially large amounts of irrigation, changed the natural distribution features of salts. With periodic irrigation, soil salt content during crop growth period was relatively low and total soil salt content displayed decreasing trends. Soil salt content decreased mainly at the seeding stage and the late blossing and boll-forming stages. Soil salt content in the 0 - 300 cm layer also decreased gradually with longer history of drip irrigation. After about 10 years of irrigation, soil salt distributed in a modified form of a plumb line. For current drip irrigation regime, it was suggested that the irrigation amount for the blossing and boll-forming stages should be properly decreased to about 618 mm in fields with an irrigation history of over 5 years. However, a relatively large amount of irrigation water should be maintained for the seedling stage.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2014年第8期149-159,共11页
Transactions of the Chinese Society for Agricultural Machinery
基金
国家自然科学基金资助项目(51369027
U1203682)
石河子大学杰青培育基金资助项目(2013ZRKXJQ02)
关键词
新疆棉区
膜下滴灌
土壤盐分
长期监测
灌溉制度
Xinjing cotton area Drip irrigation under mulch Soil salt Long-term monitoring Irrigation schedule