牧草品种与生物质炭对植草土壤水分的调控效应

目的]研究不同牧草品种种植与生物质炭施用对土壤水分的影响及其调控效应,为喀斯特石漠化区生态恢复及土壤改良提供科学依据。方法]采用盆栽试验在施用生物质炭的土壤上种植雀稗(Paspalum thunbergii)、黑麦草(Lolium perenne)、拉巴豆(Dolichos lablab),定期测定植草土壤的含水率。结果]种植雀稗、黑麦草、拉巴豆后土壤田间持水量及土壤饱和导水率均出现显著性差异,其大小顺序为:雀稗黑麦草拉巴豆,禾本科牧草种植对提高土壤持水性能的作用优于豆科牧草。施用5%的生物质炭后,雀稗、黑麦草、拉巴豆种植土壤的含水率在春夏季降雨及干旱时段均出现不同程度的增加,植草土壤田间持水量和饱和导水率则出现显著地提高,其大小顺序也为:雀稗黑麦草拉巴豆。结论]生物质炭施用明显地提高了土壤持水能力,从而有利于牧草生长。

Impacts of Different Forage Species and Biochar Application on Soil Moisture

Objective] The impacts of different forage species and biochar application on soil moisture were studied in order to provide a scientific support for ecological restoration and soil improvement in karst rocky desertification areas.Methods] The pot experiment was conducted with Paspalum thunbergii, Lolium perenne and Dolichos lablab and with the soils mixed with biochar, and the soil moisture content was periodically determined.Results] There were significant differences in soil water holding capacity and soil saturated hydraulic conductivity among P. thunbergii, L. perenne and D. lablab, with the order as follows:P. thunbergii > L. perenne > D. lablab. After applying 5% biochar, the soil water content of P. thunbergii, L. perenne and D. lablab increased to certain degrees on rainy or dry days of spring and summer, and the soil water holding capacity and saturated hydraulic conductivity of planting grass significantly increased, and the order was also P. thunbergii > L. perenne > D. lablab.Conclusion] Biochar application obviously improved soil water holding capacity, which was beneficial to pasture growth.