摘要
为了解不同宽度冲刷槽对坡面冲刷侵蚀过程中产流产沙的影响,该研究以崩岗崩积体为对象,通过不同冲刷槽宽度(10、20、30、40、50 cm)和不同单宽流量(1.2×10-2、2.4×10-2、3.6×10-2、4.8×10-2 m2/min)相结合的室内模拟冲刷试验,研究不同宽度冲刷槽对崩积体产流产沙的影响。结果表明:1)单宽流量为1.2×10-2,2.4×10-2,3.6×10-2 m2/min时,不同冲刷槽宽度之间径流率、产沙率存在显著差异(P<0.05);单宽流量为4.8×10-2 m2/min时,不同冲刷槽宽度之间径流率、产沙率差异不显著。2)单宽流量一定,不同冲刷槽宽度下径流率随时间变化趋势相同;单宽流量为1.2×10-2 m2/min时,不同冲刷槽宽度条件下产沙率和含沙量随时间变化趋势不同,其他单宽流量下产沙率和含沙量随时间变化趋势相同。3)单宽流量相同,不同冲刷槽宽度下累积径流量差异不显著;单宽流量为1.2×10-2,2.4×10-2,3.6×10-2 m2/min条件下,不同冲刷槽宽度下累积产沙量和平均含沙量差异显著(P<0.05)。该研究揭示了冲刷槽宽度对崩积体产流产沙的影响,为今后试验冲刷槽宽度的选择提供参考。
Collapsing hill is the typical and serious erosion phenomenon in the red soil area of southern China. The colluvial deposit erosion is the main sediment source of collapsing hill, which has the characteristics of loose texture, bad structure, and high erodibility. Study of the influence of elements on erosion sediment in the process of slope erosion is of great significance for revealing the mechanism of slope erosion. The width of scouring flumes is one of the factors that affect the characteristics of erosion and yield of runoff and sediment in the process of slope scouring erosion but now has fewer research achievements. With the colluvial deposits of collapsing hill as the research object, and through the simulated scouring in laboratory, this study intended to disclose the impacts of different width of scouring flumes（10, 20, 30, 40 and 50 cm） and discharge per unit width（1.2×10^-2, 2.4×10^-2, 3.6×10^-2 and 4.8×10^-2 m^2/min） on the slope scouring erosion and runoff and sediment yield of colluvial deposits. Soil samples were collected from the Longmen Town, Anxi County, Fujian Province in southeast China, and preprocessed according to the experimental standards. Results showed that： 1） The width of scouring flumes had significant effects on the runoff rate and sediment yield rate when the discharge per unit width was 1.2×10^-2, 2.4×10^-2 and 3.6×10^-2 m^2/min（P〈0.05）, while had no significant effects when the discharge per unit width was 4.8×10^-2 m^2/min; 2） When the discharge per unit width was 1.2×10^-2 m^2/min, the runoff rate increased gradually with the increase in time, when the discharge per unit width was 2.4×10^-2 and 3.6×10^-2 m^2/min, the runoff rate increased at first and then became stable with the increase in time, and when the discharge per unit width was 4.8×10^-2 m^2/min, the runoff rate increased at first and then decreased with the increase in time; when the discharge per unit width was 1.2×10^-2 m^2/min, the trends of sediment yield rate and sediment concentration over time under different width of scouring flumes were different, and when the width of scouring flumes was 10, 20 and 30 cm, the sediment yield rate and sediment concentration increased at first and then became fluctuant, but increased with time all the way while the width of scouring flumes was 40 and 50 cm; when the discharge per unit width was 2.4×10^-2, 3.6×10^-2 and 4.8×10^-2 m^2/min, the sediment yield rate and sediment concentration under each width of scouring flumes showed an increase-stability-decrease trend with the increase in time; 3） When the discharge per unit width was constant, the difference of the cumulative runoff yield under different width of scouring flumes was not significant, and that of the cumulative sediment yield and the average sediment concentration were significant（P〈0.05） while the discharge per unit width was 1.2×10^-2, 2.4×10^-2 and 3.6×10^-2 m^2/min; when the discharge per unit width was 4.8×10^-2 m^2/min, the width of scouring flumes had no significant effects on the cumulative sediment yield and the average sediment concentration; 4） The width of scouring flumes had no effects on slope erosion and characteristics of runoff and sediment yield when the discharge per unit width was 4.8×10^-2 m^2/min, and thus, faculative width of scouring flumes could be chosen while the discharge per unit width was 4.8×10^-2 m^2/min. This research has used the colluvial deposits of collapsing hill as the research object and carried out the experiments under the condition of 15° slope, but colluvial deposits＇ characteristics（loose texture, bad structure, high erodibility） are obviously different from other soil types, and thus, more studies aiming at other soil types about the effects of different width of scouring flumes on erosion and yield of runoff and sediment are needed, and further researches can also be conducted with other slope gradients.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2016年第9期136-141,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(41001169
41571272)
国家科技支撑计划项目(2014BAD15B0303)
关键词
冲刷
沙
径流
崩岗
崩积体
冲刷槽宽度
单宽流量
scour
sand
runoff
collapsing hill
colluvial deposits
width of scouring flumes
discharge per unit width
作者简介
李学增，男，河南林州人，研究方向为土壤侵蚀与治理。福州福建农林大学资源与环境学院，350002。Email：xuezeng_li@163．com
通信作者：黄炎和，男，广东饶平人，教授，博士，博士生导师，研究方向：土壤侵蚀与治理。福州福建农林大学资源与环境学院，350002。Email：yanhehuang@163．com
