垄沟集雨覆盖种植对红豆草根系特征和产量的影响

Effects of ridge-furrow rainfall harvesting with mulching on roots characteristic and fodder yield of sainfoin

摘要:

【目的】为选择集雨垄的环境友好型覆盖材料，提高中国西北半干旱地区的降雨利用效率。 【方法】通过随机区组大田试验，以传统平作为对照，研究 3 种材料（土壤结皮、生物可降解地膜和普通地膜）覆盖垄的垄沟集雨种植对土壤水热条件、红豆草根系特征、根瘤特征、干草产量和水分利用效率的影响。【结果】垄沟集雨种植显著改善土壤水热状况，增加红豆草根系和根瘤特征值。土壤结皮覆盖垄沟集雨种植显著提高红豆草水分利用效率，但降低红豆草干草产量；生物降解地膜和普通地膜覆盖垄沟集雨种植显著提高红豆草的干草产量和水分利用效率。与传统平作相比，土壤结皮、生物降解地膜和普通地膜覆盖垄沟集雨种植的土壤贮水量分别提高 10. 64、9. 36 和 2. 09 mm，垄上表层土壤温度分别增加 2. 0、3. 4 和 4. 2 ℃，红豆草根干重分别提高 27%、72% 和 87%，有效根瘤数分别增加 2. 1、9. 1 和 12. 4 个，水分利用效率分别提高 11. 9、23. 3 和 30. 0 kg/（hm2 ·mm）。土壤结皮覆盖垄沟集雨种植的红豆草干草产量比传统平作降低 13%，生物降解地膜和普通地膜覆盖垄沟集雨种植的红豆草干草产量比传统平作分别提高 11% 和 23%。由于普通地膜残留极易导致土壤结构恶化和环境污染，不利于农业生产可持续性。【结论】在我国半干旱地区，生物可降解地膜覆盖垄沟集雨种植可作为一种高效、可持续的农业节水生产技术。

Abstract:

【Objective】 In order to select environmentally friendly mulching materials in ridge ‐furrow rainwater harvesting system （RFRH） and to increase rainwater utilization in a semiarid region of Northwest China.【Method】 A field experiment was conducted using a randomized complete design to determine effects three ridge ‐mulching materials （manually compacted soil （SR），biodegradable film （BR），and plastic film （PR）） on soil water storage，topsoil temperature，root characteristics （length，surface area，volume，and weight of roots） and nodule characteristics （number and weight of root nodules），fodder yield，and water use efficiency （WUE） of sainfoin in 2016，using traditional flat planting （TP） as a control.【Result】 The results showed that the practice of RFRH，especially BR and PR，resulted in increased soil water storage at furrow bottoms and topsoil temperature at ridge tops，and improved root and nodule characteristics of sainfoin. SR increased WUE，but decreased fodder yield. BR and PR increased fodder yield and WUE. Compared with TP，the soil water storage increased by 10. 64，9. 36 and 2. 09 mm，respectively. Topsoil temperature at ridge tops increased by 2. 0，3. 4 and 4. 2 ℃ respectively. Dry root weight increased by 27%， 72% and 87%respectively. WUE increased by 11. 9，23. 3 and 30. 0 kg/（hm2 ·mm） during the sainfoin growth seasons，respectively for SR，BR and PR. The fodder yield for SR decreased by 13%，but the fodder yield for BR and PR increased by 11% and 23%，respectively. Intensive use of plastic films in agro ‐ ecosystems had raised considerable concerns due to the increasing film residues in soils.【Conclusion】 The ridge furrow rainwater harvesting mulching with biodegradable film was a suitable tillage technology for sainfoin production in semiarid regions.