【摘要】：為了評價黃土高原丘陵區(qū)退耕還草水土保持效應,本研究以黃土丘陵區(qū)冰草(Agropyron cristatum)和柳枝稷(Panicum virgatum)為研究對象,在不同坡度(S=17.36%~42.26%)和流量(Q=1.0~2.5L·s~(-1))條件下,采用變坡試驗水槽測定土壤的分離能力,利用線性回歸方法,結合土壤侵蝕過程,運用WEPP模型推求土壤細溝可蝕性(Kr),分析了冰草和柳枝稷生育期內土壤Kr的季節(jié)變化規(guī)律。結果表明,黃土丘陵區(qū)冰草生育期內土壤Kr具有顯著的季節(jié)變化(P0.05),總體呈下降趨勢;柳枝稷生育期內土壤Kr無顯著季節(jié)變化(P0.05)。冰草土壤Kr表現為下降的季節(jié)變化,變化范圍為0.002 1~0.022 4s·m~(-1);柳枝稷土壤Kr表現為先升高后降低的季節(jié)變化,變化范圍為0.003 2~0.021 9s·m~(-1)。土壤黏結力、水穩(wěn)性團聚體和根重密度是影響冰草和柳枝稷生育期內土壤Kr季節(jié)變化的主要因素。土壤細溝可蝕性與土壤黏結力、水穩(wěn)性團聚體及根重密度間呈顯著負相關關系。此外,用土壤黏結力和根重密度能夠較好地模擬黃土丘陵區(qū)冰草和柳枝稷生育期內土壤細溝可蝕性的季節(jié)變化。冰草和柳枝稷土壤細溝可蝕性季節(jié)變化主要由根系生長和土壤黏結力變化所致。土壤細溝可蝕性與土壤黏結力、水穩(wěn)性團聚體和根重密度間呈顯著負相關關系。用土壤黏結力和根重密度等參數能夠較好地模擬冰草和柳枝稷土壤細溝可蝕性的季節(jié)變化規(guī)律。
[Abstract]:In order to evaluate the effect of soil and water conservation on the soil and water conservation in the hilly area of the Loess Plateau, the study was carried out in the condition of different slope (S = 17.36% ~ 42.26%) and flow (Q = 1.0 ~ 2.5 L 路 s ~ (-1)). The soil separation ability was determined by the variable slope test water tank, and the soil erosion (Kr) was calculated by the WEPP model by using the linear regression method, and the seasonal variation of the soil Kr in the growth period of the ice grass and the willow branch was analyzed. The results showed that there was a significant seasonal change in the soil Kr during the growth period of the ice-grass in the hilly region of the loess region (P0.05), and there was no significant seasonal change in the soil Kr during the growth period of the willow branch (P0.05). The seasonal variation of Kr in the ice-grass soil was in the range of 0.002 1-0.022 4 s 路 m ~ (-1), and the soil Kr in the Liuzhi-grass was the seasonal variation after the increase, and the range of variation was 0.003 2-0.021 9s 路 m ~ (-1). The soil adhesion, the water-stability aggregates and the root-weight density are the main factors that affect the seasonal variation of the soil Kr in the growth period of the ice grass and the willow branch. There was a significant negative correlation between the erodibility of the soil fine trench and the soil adhesion, the aggregate of the water-stability and the density of the root. In addition, the seasonal variation of the erodibility of the soil in the growth period of the ice grass and the willow branch in the loess hilly region can be well simulated by the soil adhesion and the density of the root. The seasonal variation of the erodibility of the fine trench in the soil of the ice grass and the willow branch is mainly caused by the root system growth and the change of the soil adhesion. There was a significant negative correlation between the erodibility of the soil fine trench and the soil adhesion, the aggregate of the water-stability and the density of the root. The seasonal variation of the erodibility of the fine trench in the soil of the ice and the willow branches can be simulated better with the parameters such as the soil adhesion and the density of the root.
【作者單位】： 寶雞文理學院地理與環(huán)境學院;陜西省災害監(jiān)測與機理模擬重點實驗室;
【基金】：國家自然科學基金項目(41371497、41171423、41601016) 陜西省教育廳重點實驗室項目(2010JS072、2009JS071) 寶雞文理學院重點科研項目(ZK2017039、ZK2017040)
【分類號】：S157
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本文編號：2432385