發(fā)布時間：2018-06-08 03:52

  本文選題：不同放牧制度 + 土壤蒸發(fā)　； 參考：《內蒙古農業(yè)大學》2017年博士論文

【摘要】：呼倫貝爾草原是全世界范圍內最大的天然草原,草地水草肥美,與大興安嶺共同構筑了我國北方的生態(tài)屏障。但是近年來,隨著社會經濟持續(xù)快速發(fā)展,草原上超載放牧現象嚴重,草原上牲畜-植被-水之間的問題一直困擾著草原的生態(tài)環(huán)境的和諧發(fā)展。本文以呼倫貝爾草原不同放牧草場為研究對象,結合野外測試和模型模擬,調查不同放牧制度草場生態(tài)特性及土壤剖面特征,選定相應草場試驗場,測定不同放牧制度草場利用方式對植被、土壤、生態(tài)環(huán)境的影響,通過在試驗場模擬降雨試驗、土壤蒸發(fā)試驗、蒸發(fā)入滲試驗,測定相應的土壤流失量、營養(yǎng)元素流失量、植被截留量和土壤蒸發(fā)量等參數。利用有效混合深度模型、改進王彥輝模型、作物系數模型與飛利浦入滲模型等對不同放牧草地的土壤水文狀況進行模擬,采用模糊數學法對草地土壤健康狀況進行了評價。探討草地在不同放牧制度影響下土壤水文循環(huán)及其生態(tài)效應的變化規(guī)律,為草地資源的可持續(xù)發(fā)展提供依據。主要結論如下:(1)三種放牧草場0-80cm深土壤的物理、化學、生物特性差異顯著(P0.05),三種放牧草場土壤物理性質變化無明顯規(guī)律。土壤中氮磷鉀等元素含量變化差異較大,總體顯示隨深度的增加逐漸增大。多酚氧化酶、蔗糖酶、脲酶活性退化程度變化趨勢基本一致,均隨土壤深度的增加而逐漸減小,且休牧草場輪牧草場自由放牧草場。(2)三種放牧草場土壤入滲率為休牧草場輪牧草場自由放牧草場,有壓入滲速率高于無壓入滲速率,無壓入滲和有壓入滲均符合冪函數擬合關系。利用Horton模型、Philip模型、Kostiakov模型模擬不同放牧制度草地土壤入滲過程,其中Horton模型模擬效果最好,Kostiakov模型效果最差。休牧草場土壤蒸發(fā)量為0.884mm/day,輪牧草場土壤蒸發(fā)量為0.817 mm/day和自由放牧草場土壤蒸發(fā)量為0.794 mm/day。土壤含水率與土壤蒸發(fā)量相關系數最高為0.503-0.558,參考作物模型計算不同放牧制度草地土壤蒸發(fā)量,三種放牧草場土壤蒸發(fā)量的計算值和實測值基本變化趨勢吻合,自由放牧草場相關系數為0.95,納什系數為0.76,輪牧草場相關系數為0.92,納什系數為0.71,休牧草場相關系數為0.91,納什系數為0.63。(3)休牧、輪牧、自由放牧草場通過水浸泡法測得的截留量分別為0.675mm、0.413mm、0.287mm,降雨模擬實驗測得的截留量分別為1.110mm、0.734mm、0.497mm。三種放牧草場整體植被截留量與植被覆蓋度和葉面積、降雨量相關性較好,截留量與降雨量呈對數相關關系,與降雨強度間的關系呈拋物線。利用植被的蓋度、株高、生物量、葉面積指數與截留量間的關系,建立整體植被截留非線性回歸模型,模型的模擬效果較好,相關系數可以達到0.89以上。在非線性回歸模型的基礎上改進王彥輝模型,對整體植被截留量進行模擬,模擬效果較好相關系數均達到0.9以上。(4)三種放牧草場在相同降雨強度下產流量和產砂量均顯示為自由放牧草場輪牧草場休牧草場。降雨強度對不同放牧草場的泥沙流失量影響明顯,并且隨降雨強度的增加,流失土壤中粘性粒及粉性粒所占比例上升。三種放牧草場總氮流失量為高雨強時自由放牧草場流失最多,輪牧草場次之,休牧草場流失最少,中低雨強時輪放草場與自由放牧草場流失量相近,休牧草場流失最少。三種放牧草場總磷流失量為自由放牧草場最多,休牧草場次之,輪牧草場最少�；旌仙疃饶Ｐ湍M三種放牧制度草場氮磷流失過程,不完全混合模型的模擬結果優(yōu)越于完全混合模型,氮流失過程模擬精度小于5%,磷模擬精度小于10%。(5)從土壤物理、化學、生物特性和草地生態(tài)水文特性出發(fā)對草地進行健康評價,得出休牧草場處于健康狀態(tài),輪牧草場處于亞健康狀態(tài)或健康狀態(tài),自由放牧草場處于不健康狀態(tài)。
[Abstract]:Hulun Buir Grassland is the largest natural grassland in the world. The grassland water grass is rich and the ecological barrier of northern China is built together with Greater Khingan Range. But in recent years, with the rapid and rapid development of the social economy, the overgrazing phenomenon on the grassland is serious. The problem of livestock, vegetation and water on the grassland has been puzzling the ecological ring of the grassland. In this paper, we take the different grazing grassland in Hulun Buir Grassland as the research object, combine the field test and model simulation, investigate the ecological characteristics and soil profile characteristics of different grazing systems, select the corresponding grassland test field, and determine the effects of different grazing systems on the vegetation, soil and the ecological environment. The field simulated rainfall experiment, soil evaporation test and evaporation infiltration test were used to determine the corresponding soil loss, nutrient loss, vegetation interception and soil evaporation. Using the effective mixing depth model, the improved Wang Yanhui model, the crop coefficient model and the PHILPS infiltration model were applied to the soil hydrology of different grazing grassland. The fuzzy mathematical method was used to evaluate the health status of grassland soil. The changes of the soil hydrological cycle and its ecological effects under the influence of different grazing systems were discussed. The main conclusions were as follows: (1) the physical, chemical and biological characteristics of the 0-80cm deep soil in the three pasture pastures were as follows. The variation of soil physical properties of three pasture pastures was not obvious. The changes of the contents of N, P, K and other elements in the soil varied greatly, and the overall show increased with the increase of depth. The trend of the degradation of polyphenol oxidase, sucrase and urease activity was the same, and decreased gradually with the increase of soil depth. (2) the soil infiltration rate of the three grazing pastures is the free grazing grassland in the pasture pasture, and the pressure infiltration rate is higher than the non pressure infiltration rate, the pressure infiltration and the pressure infiltration are all fitted with the power function fitting relationship. The Horton model, the Philip model and the Kostiakov model simulated the different grazing systems. In the process of infiltration of grassland soil, the Horton model has the best simulation effect and the Kostiakov model has the worst effect. The soil evaporation of the Hugh pasture is 0.884mm/day, the soil evaporation of the grazing grassland is 0.817 mm/day and the soil evaporation of the free grazing grassland is 0.794 mm/day., and the correlation coefficient of soil moisture content and soil soil evaporation is the highest for reference. The crop model calculated the soil evaporation in different grazing systems. The calculated values of soil evaporation in three grazing pastures coincided with the measured values. The correlation coefficient of free grazing grassland was 0.95, the Nash coefficient was 0.76, the correlation coefficient of the pasture was 0.92, the Nash coefficient was 0.71, the correlation coefficient of the herd pasture was 0.91, and the Nash coefficient was 0.. 63. (3) herding, rotational grazing and free grazing grassland were measured by water immersion method (0.675mm, 0.413mm, 0.287mm). The interception measured by the simulated rainfall experiment was 1.110mm, 0.734mm, 0.497mm., the total vegetation interception of three grazing pastures was related to the vegetation coverage and leaf area, the rainfall was better, the interception and rainfall were the same. The relationship between several correlation and rainfall intensity is parabola. Using the relationship between vegetation coverage, plant height, biomass, leaf area index and interception, the whole vegetation interception nonlinear regression model is established. The simulation results of the model are better and the correlation coefficient can reach 0.89. On the basis of nonlinear regression model, the improvement of Wang Yanhuimo is improved. The total vegetation interception was simulated. The good correlation coefficient of the simulated results reached more than 0.9. (4) the yield and sand yield of three grazing pastures under the same rainfall intensity were all displayed in the free grazing grassland. The rainfall intensity had a significant effect on the sediment loss in different grazing pastures, and the rainfall intensity was observed with the rainfall intensity. In the three grazing pastures, the total nitrogen loss in the lost soil was increased. The loss of total nitrogen in the grazing grassland was the highest in the high rain intensity, the grazing grassland was the most, the grazing grassland was the least, the low rainfall intensity was close to the free grazing grassland, the loss of the herd pasture was the least. The total phosphorus in the pasture pasture was three. The loss amount is the most free grazing grassland, the rest pasture is the next, and the grazing grassland is the least. The mixed depth model simulates the nitrogen and phosphorus loss process in the three grazing systems. The simulation results of the incomplete mixing model are superior to the complete mixing model, the simulation precision of nitrogen loss process is less than 5%, the phosphorus simulation precision is less than 10%. (5) from soil physics, chemistry and biology. The grassland was in a healthy state, and the grazing grassland was in subhealth or healthy state, and the free grazing grassland was in an unhealthy state.
【學位授予單位】：內蒙古農業(yè)大學
【學位級別】：博士
【學位授予年份】：2017
【分類號】：S812
，

本文編號：1994332