典型草原不同放牧强度及放牧方式下牛羊食性选择研究

发布时间：2018-08-13 18:53

【摘要】：放牧是天然草原的主要利用方式,也是草原管理的重要手段。采食行为是放牧生态学研究的核心,草原生态系统中群落特征影响家畜的食性选择,家畜的采食又反作用于群落,家畜与植物之间具有密切的相互作用。本文以内蒙古锡林郭勒典型草原为例,通过设置轻度、中度和重度三个放牧梯度和牛羊单牧与混牧三种放牧方式,系统分析不同放牧强度与放牧方式对家畜食性的影响,这一研究对深入揭示放牧生态系统中动-植物相互关系及草地生态系统的可持续管理有一定的理论意义和应用价值。主要研究结论如下:1)放牧强度显著影响主要种群相对生物量及群落多样性。大针茅的相对生物量随放牧强度增加而显著增加,羊草显著降低;SimPson指数、Shannon-wiener指数、Pielou均匀度等多样性指数均随着放牧强度的增加而显著降低。2)相同牧压梯度下,3种放牧方式对主要种群相对生物量及群落多样性没有显著影响。与对照相比,所有放牧方式大针茅的相对生物量均显著增加,而羊草显著降低;SimPson指数、Shannon-wiener指数、Pielou均匀度等多样性指数显著降低。各主要种群的相对生物量及上述多样性指数各放牧方式间均无显著差异。3)不同放牧强度与放牧方式下,牛羊食谱有明显差异,其中羊主要采食羊草、知母、糙隐子草等,而牛采食大针茅比例较高。随着放牧强度的增加绵羊采食大针茅的比例增加,而采食羊草的比例降低。4)放牧强度与放牧方式对牛羊的选择性采食有一定的影响。轻牧、中牧条件下,绵羊都较喜食羊草和知母,不喜食大针茅;重牧条件下,羊草由嗜食变为少食,大针茅由可食变为喜食。大针茅在羊单牧时羊不喜食,牛羊混牧时成为喜食或可食,而牛在不同的放牧方式均喜食;羊草不论何种放牧方式牛羊均喜食。5)放牧强度、放牧方式及放牧时期显著影响绵羊和牛对羊草的采食方式,且二者具有交互作用。牛、羊对羊草的采食方式主要以去顶和摘叶为主,去顶率牛单牧显著低于羊单牧和牛羊混牧,但不受放牧强度的影响;摘叶率、拔心率随着放牧强度的增加而显著增加,但不受放牧方式的影响。去顶率随着放牧时期的延续先显著降低后显著增加,摘叶率不同放牧强度变化规律与其相同,不同放牧方式变化规律与其相反;拔心率不受放牧时期的影响。
[Abstract]:Grazing is the main use of natural grassland, and also an important means of grassland management. Grazing behavior is the core of grazing ecology research. The community characteristics in grassland ecosystem affect the feeding choice of livestock, and the feeding behavior of livestock counteracts to the community, and there is close interaction between livestock and plant. Taking the typical grassland of Xilinguole, Inner Mongolia as an example, the effects of different grazing intensities and grazing patterns on the feeding habits of domestic animals were systematically analyzed by setting three gradients of light, moderate and severe gradients and three grazing modes of cattle and sheep single grazing and mixed grazing. This study has certain theoretical significance and application value in revealing the relationship between animal and plant in grazing ecosystem and sustainable management of grassland ecosystem. The main results were as follows: (1) grazing intensity significantly affected the relative biomass and community diversity of the main population. The relative biomass of Stipa grandis increased significantly with the increase of grazing intensity. The diversity index of Shannon-wiener index and Pielou evenness of Leymus chinensis decreased significantly with the increase of grazing intensity. 2) under the same grazing pressure gradient, three grazing patterns had no significant effect on the relative biomass and community diversity of the main population. Compared with the control, the relative biomass of Stipa grandis increased significantly in all grazing methods, while the diversity index such as Shannon-wiener index and Pielou evenness index of Leymus chinensis decreased significantly. There was no significant difference in relative biomass and diversity index among the main populations. 3) under different grazing intensities and grazing patterns, the diets of cattle and sheep were significantly different. However, the proportion of fescue fed by cattle was higher. With the increase of grazing intensity, the proportion of sheep feeding on Stipa grandis increased, while the proportion of sheep fed on Leymus chinensis decreased by 4. 4) the grazing intensity and grazing mode had a certain effect on the selective feeding of cattle and sheep. Light grazing, medium grazing conditions, sheep prefer to eat Leymus chinensis and Anemarrhena, do not like to eat Stipa grandiflora; heavy grazing conditions, Leymus chinensis from diet to eat less, from edible to like to eat. When the fescue was single grazing, the sheep did not like to eat, but when the cattle and the sheep were mixed, they liked to eat or could eat, while the cattle liked to eat in different grazing ways; the grazing intensity of the sheep and cattle was 5. 5% regardless of the grazing method. Grazing patterns and grazing periods significantly affected the feeding patterns of sheep and cattle on Leymus chinensis, and they had interaction. The feeding pattern of cattle and sheep on Leymus chinensis was mainly to remove the top and pick the leaves. The rate of single grazing of cattle was significantly lower than that of sheep and sheep, but it was not affected by the grazing intensity, and the rate of picking leaves and the heart rate of pull-out increased with the increase of grazing intensity. But it is not affected by the way of grazing. With the extension of grazing period, the topping rate decreased significantly and then increased significantly, and the change law of different grazing intensity was the same as that of different grazing intensity, but the change law of different grazing mode was opposite, and the heart rate was not affected by the grazing period.
【学位授予单位】：内蒙古大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S823;S826

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