本文選題：西藏高原 + 牦牛�。� 參考：《西北農(nóng)林科技大學(xué)》2015年碩士論文

【摘要】：本試驗在西藏林芝工布江達縣邦杰塘草原試驗站進行,試驗設(shè)置5個處理,對照即零放牧(NG)、延遲+適度放牧(DMG)、適度放牧(MG)、延遲+重度放牧(DHG)、重度放牧(HG),研究西藏高寒草甸在不同放強度下,草地植被群落的豐富度、蓋度、均勻度、高度、生物量、密度和土壤理化性質(zhì)的變化,研究結(jié)果如下:(1)在不同放牧條件下,高寒草甸植物群落結(jié)構(gòu)變化顯著(P0.05)。重度放牧(HG)時,植物群落的蓋度、均勻度和豐富度顯著減少,與適度放牧(MG)和對照(NG)差異顯著(P0.05);草地生物量在適度放牧(MG)、延遲+適度放牧(DMG)區(qū)最高,與對照之間差異顯著(P0.05),重度放牧(HG)對紫花針茅和高山嵩草的高度、蓋度和密度的影響差異達到顯著水平(P0.05)。(2)在重度放牧(HG)下,高寒草甸土壤層0~10 cm處,土壤含水量與對照差異不顯著(P0.05);隨著放牧強度的增加,家畜對草地踐踏增加,草地硬度變大,土壤透氣性變差;隨放牧強度的增加土壤體積質(zhì)量、總孔隙度和毛管孔隙度顯著增加(P0.05),且隨土層深度的增加而減少,其差異達到顯著水平(P0.05)。(3)隨著放牧強度的增加,土壤中速效氮、速效鉀、全氮和全磷含量減少;全鉀含呈先增加后減小的趨勢;重度放牧和延遲+重度放牧顯著降低了土壤中速效氮、速效磷和速效鉀及全氮、全鉀的含量;土壤有機質(zhì)含量隨著放牧強度的增加而逐漸減少;不同的放牧強度對土壤pH值影響不顯著(P0.05)。(4)隨著放牧強度的增加牦牛增重量降低,重度放牧(HG)時牦牛增重量明顯低于適度放牧(MG);暖季放牧?xí)r,牦牛增重量顯著增加(P0.05),而在適度放牧(MG)時,牦牛增重量明顯高于重度放牧(HG)。(5)隨放牧強度的增加家畜體重和植被總蓋度顯著下降(P0.05),而高寒草甸生物量和家畜增重量在適度放牧?xí)r達到最高,在重度放牧下,草地的生物量和牦牛增重量顯著降低。
[Abstract]:The experiment was carried out at the Bang Jie Tang prairie experimental station of Gongbujiangda County, Linzhi, Tibet. Five treatments were set up in the experiment. In contrast, zero grazing (NG), delayed moderate grazing (DMG), moderate grazing (MG), delayed heavy grazing (DHG), heavy grazing (HG) were used to study the richness, coverage, evenness, height, biomass of grassland vegetation community in Tibetan alpine meadow under different radiation intensities. The changes of density and soil physical and chemical properties were as follows: (1) under different grazing conditions, the plant community structure of alpine meadow changed significantly (P0.05). Under heavy grazing (HG), the coverage, evenness and richness of plant community decreased significantly, which was significantly different from that of moderate grazing (MG) and control (NG) (P0.05), and the biomass of grassland was the highest in moderate grazing (MG) and delayed moderate grazing (DMG). The effect of heavy grazing (HG) on the height, coverage and density of Stipa lanceolata and Kobresia alpine reached a significant level (P0.05). (2). Under heavy grazing (HG), the soil layer of alpine meadow was 0 ~ 10 cm. There was no significant difference between soil moisture content and control (P0.05); with the increase of grazing intensity, livestock trampled on grassland increased, grassland hardness increased, soil permeability became worse; with the increase of grazing intensity, soil volume quality, The total porosity and capillary porosity increased significantly (P0.05), and decreased with the increase of soil depth. The difference reached a significant level (P0.05). (3). With the increase of grazing intensity, the contents of available nitrogen, available potassium, total nitrogen and total phosphorus decreased with the increase of grazing intensity. The contents of available nitrogen, available phosphorus, available potassium, total nitrogen and total potassium in the soil decreased significantly with the increase of grazing intensity, and the content of organic matter in the soil gradually decreased with the increase of grazing intensity. The effect of different grazing intensity on soil pH value was not significant (P0.05). (4). With the increase of grazing intensity, the weight gain of yak decreased, while that of heavy grazing (HG) was significantly lower than that of moderate grazing (MG), and that of warm season grazing was significantly lower than that of moderate grazing (MG). The weight gain of yak was significantly increased (P0.05), but at moderate grazing (MG), The weight gain of yak was significantly higher than that of heavy grazing (HG). (5). With the increase of grazing intensity, the body weight and total vegetation coverage of yak decreased significantly (P0.05), while the biomass and weight gain of alpine meadow reached the highest in moderate grazing. The biomass of grassland and weight gain of yak decreased significantly.
【學(xué)位授予單位】：西北農(nóng)林科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：S812

【參考文獻】

相關(guān)期刊論文 前1條

1 邊巴卓瑪;呼天明;吳紅新;;依靠西藏野生牧草種質(zhì)資源提高天然草場的植被恢復(fù)效率[J];草業(yè)科學(xué);2006年02期

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本文編號：2099191