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为了研究云南省元阳县梯田核心区土壤的侵蚀特性和保水机制,采用原状土冲刷槽法和实地放水冲刷试验法,结合有林地、灌木林地、荒草地和坡耕地的物理性质等,对元阳梯田核心区上述4种土地利用类型表层土壤抗冲性及其主要影响因素进行研究。结果表明:研究区表层土壤抗冲性由强到弱表现为荒草地>灌木林地>有林地>坡耕地;含沙量随着坡度(15°、30°和45°)和冲刷流量(1.5、2.5和3.0 L/min)的增加而增加,坡耕地具有较弱的抗冲性;土壤中的须根能够增强土壤的抗冲能力,特别是直径<1.0 mm的须根具有较强的固结性;土壤的水稳性团聚体越多土壤的抗冲性也就越好,荒草地和灌木林地表层土壤直径>3 mm的土粒,其结构水稳度为93.33%。
In order to study the erosion characteristics and water retention mechanism of the terraces in the core area of Yuanyang County in Yunnan Province, using the original soil erosion tank method and the field water scouring test method, combined with the physical properties of forest land, shrub land, weeds and sloping land, The four types of land-use surface soil anti-scourability and its main influencing factors in the core area of Yangtiantian were studied. The results showed that the surface soil anti-scourability in the study area showed as follows: grassland> shrub land> forest land> sloping farmland; the sediment concentration increased with slope (15 °, 30 ° and 45 °) and scour flow (1.5, 2.5 and 3.0 L / min), and the slope farmland had weaker impact resistance. The fibrous roots in the soil could enhance the soil’s impact resistance, especially the fibrous roots with diameter <1.0 mm had strong consolidation; Soil water stable aggregates the better the soil impact resistance, grassland and shrub land topsoil diameter> 3 mm of soil particles, the structure of water stability of 93.33%.