农业工程学报
農業工程學報
농업공정학보
2009年
10期
25-29
,共5页
田风霞%刘刚%郑世清%马春艳%张琼
田風霞%劉剛%鄭世清%馬春豔%張瓊
전풍하%류강%정세청%마춘염%장경
水动力学%径流%人工降雨%覆盖度%土质路面%减水减沙
水動力學%徑流%人工降雨%覆蓋度%土質路麵%減水減沙
수동역학%경류%인공강우%복개도%토질로면%감수감사
hydrodynamic%runoff%cloud seeding%coverage degree%terrene road%runoff and sediment reduction
通过室内人工模拟降雨,研究了草本植物不同覆盖度土质路面的径流水动力学特征以及路面的产流产沙过程.结果表明,路面径流的弗劳德数和雷诺数属层流的急流范畴,并且二者与径流流速及过水断面单位能量相同,均随草本植物覆盖度的增大而减小.而Darcy-weisbach阻力系数以及曼宁糙率系数则均随覆盖度的增大而增大.在不同覆盖度土质路面上,径流量随径流时间急剧增大后趋于稳定,且二者符合移轴双曲线关系,而输沙率则经历了先增大后减小的过程.随着植被覆盖度的增大,土质道路的水分入渗率逐渐增大,而径流量、输沙率及含沙率均逐渐减小.该研究表明土质路面种植的草本植物具有较好的水土保持功能,为阐明草本植物与土壤侵蚀的关系提供了理论依据.
通過室內人工模擬降雨,研究瞭草本植物不同覆蓋度土質路麵的徑流水動力學特徵以及路麵的產流產沙過程.結果錶明,路麵徑流的弗勞德數和雷諾數屬層流的急流範疇,併且二者與徑流流速及過水斷麵單位能量相同,均隨草本植物覆蓋度的增大而減小.而Darcy-weisbach阻力繫數以及曼寧糙率繫數則均隨覆蓋度的增大而增大.在不同覆蓋度土質路麵上,徑流量隨徑流時間急劇增大後趨于穩定,且二者符閤移軸雙麯線關繫,而輸沙率則經歷瞭先增大後減小的過程.隨著植被覆蓋度的增大,土質道路的水分入滲率逐漸增大,而徑流量、輸沙率及含沙率均逐漸減小.該研究錶明土質路麵種植的草本植物具有較好的水土保持功能,為闡明草本植物與土壤侵蝕的關繫提供瞭理論依據.
통과실내인공모의강우,연구료초본식물불동복개도토질로면적경류수동역학특정이급로면적산유산사과정.결과표명,로면경류적불로덕수화뢰낙수속층류적급류범주,병차이자여경류류속급과수단면단위능량상동,균수초본식물복개도적증대이감소.이Darcy-weisbach조력계수이급만저조솔계수칙균수복개도적증대이증대.재불동복개도토질로면상,경류량수경류시간급극증대후추우은정,차이자부합이축쌍곡선관계,이수사솔칙경력료선증대후감소적과정.수착식피복개도적증대,토질도로적수분입삼솔축점증대,이경류량、수사솔급함사솔균축점감소.해연구표명토질로면충식적초본식물구유교호적수토보지공능,위천명초본식물여토양침식적관계제공료이론의거.
Indoor rainfall simulation was employed to investigate the hydraulic characteristics of runoff, and runoff generation and sediment generation processes on terrene roads with different coverage degrees of herbaceous plants. The study indicated that on the roads the Froude numbers and Reynolds numbers of runoff fell into the category of supercritical flow of laminar flow. Their unit energies were consistent with the runoff velocity and water-carrying section, which were decreased with the increasing of the coverage degrees of herbaceous plants. The Manning roughness coefficients and the Darcy-weisbach friction coefficients increased as the coverage degrees increased. On the terrene roads with different coverage degrees, the amounts of runoff initially increased sharply and then stabilized with runoff-lasting time. Both the amounts of runoff and the runoff-lasting time were following an offset hyperbola, whereas the sediment yield rates initially increased and then declined. With the increasing of coverage degrees, the infiltration rates of water into the terrene roads gradually increased and the amounts of runoff, sediment yield rates and sediment concentration all gradually decreased. The study revealed that on terrene roads herbaceous plants could play a favorable role in soil and water conservation and provided a theoretical basis for understanding the relations between herbaceous plants and soil erosion.