官麦地小流域径流场产流产沙特征

Characteristics of Runoff and Sediment Production of Runoff Plot of Guanmaidi Small Watershed

为了研究官麦地小流域不同土地利用类型的产流产沙特征,按流域地形和用地类型,在小流域内布设了坡耕地、坡改梯、经果林、水保林、新造水保林、荒草地6个径流小区。研究2014年6—10月各径流小区的产流产沙量,对各径流小区的产流产沙量、降雨与产流产沙量、下垫面条件与产流产沙量进行回归分析,结果显示:各小区产流量为坡耕地(11.479 m3)>荒草地(8.109 m3)>坡改梯(6.488 m3)>新造水保林(3.119 m3)>经果林(2.937 m3)>水保林(2.695m3);产沙量为坡耕地(213.916 6 kg)>荒草地(47.077 3 kg)>坡改梯(32.816 9 kg)>新造水保林(13.686 2 kg)>经果林(4.566 0 kg)>水保林(3.378 9 kg);产流量和产沙量随着降雨量的增加而增加,产流量与产沙量具有极显著的相关性,土壤的物理性质和植被总盖度与水土流失关系密切。试验结果表明水土保持措施对于径流和泥沙具有非常好的削减作用。

In order to study the characteristics of runoff generation and sediment production of different land use types of Guanmaidi small watershed,it laid out 6 runoff plots of slope farmland,terracing farmland,orchards,soil and water conservation forest,newly planted soil and water conservation forest and wild grass land according to the topography and land use types of the watershed. It studied the runoff generation and sediment production of each runoff plot in the period of June to October 2014 and conducted regression analysis on runoff generation with sediment production,precipitation with runoff and sediment production and conditions of underlying surface with runoff and sediment production of each runoff plot. The outcomes show that a) the runoff generation is slope farmland( 11. 479 m3) > wild grass land( 8. 109 m3) >terracing farmland( 6. 488 m3) > newly planted soil and water conservation forest( 3. 119 m3) > orchards( 2. 937 m3) > soil and water conservation forest( 2. 695 m3); b) the sediment production is slope farmland( 213. 916 6 kg) > wild grass land( 47. 077 3 kg) > terracing farmland( 32. 816 9 kg) > newly planted soil and water conservation forest( 13. 686 2 kg) > orchards( 4. 566 0 kg) > soil and water conservation forest( 3. 378 9 kg) and; c) the runoff yield and sediment production are increased along with the increase of rainfall and they have extremely significant correlation. The physical properties of soil and vegetation coverage have a close relationship with soil and water loss. It shows that soil and water conservation measures have very good effect on runoff and sediment reduction.