牧区典型草原不同放牧方式下的草原群落变迁研究

发布时间：2018-04-14 03:34

本文选题：牧区典型草原 + 不同放牧方式　；参考：《内蒙古师范大学》2017年硕士论文

【摘要】：温带典型草原从半干旱区逐步扩展到半湿润区,是陆地上最大的生态系统类型之一。它不仅是蒙古高原草原区广大人民赖以生存的物质基础,也是蒙古高原草原区荒漠化和应对区域气候变化的重要屏障。牧户主要依靠放牧来利用草场资源,放牧方式是否合理,将直接地或间接地影响到典型草原区生态系统的结构和功能。因此,加强放牧方式管理是牧区典型草原管理的核心。放牧方式作为放牧管理体系,一直受到国内外学者和政府部门的普遍关注和重视。因此,本文采用理论研究与实地调查相结合的方法,通过分析蒙古国纳兰苏木和我国阿巴嘎旗北部那仁宝拉格苏木两个相同自然地理背景的区域作为研究区,使用NDVI并采用最大合成法对牧业两个苏木NDVI进行了动态监测和2016年实地草场取样测试资料为基础。分析草原放牧方式的变革过程对草原群落变迁的影响,研究结果如下:(1)蒙古国纳兰苏木放牧方式由非定域游牧转为了定域游牧,目前主要以季节性迁移为主,结合了草场游动性放牧和季节性营盘分段放牧,这使草场植被有充分的恢复机遇,减少了放牧家畜的践踏压力,也充分体现了草原优良牧草的比例和NDVI与牲畜结构多样性之间的耦合关系。但由于近年来牲畜头数的增加,牲畜结构的变化,草场面积的减少,导致放牧场受不同程度的践踏而退化。1989~2011年的NDVI一级植被指数较少,没有太大的变化;2011~2016年之间二级NDVI值面积减少了53.97%。群落组成以克氏针茅+冷蒿群落变为羊草+克氏针茅、冰草群落混合,主要优势种为羊草(Leymus chinensis)、克氏针茅(Stipa krylovii),伴生种为寸草苔(Carex duriuscula)、大针茅(Stipa grandis P.Smirn.)常见植物种为冰草(Agropyron cristatum)、冷蒿(Artemisia frigida)、木地肤(Kochia prostrate)、多根葱(Ajania polyrrhizum)等。还有增加了一年生植物。(2)内蒙古那仁宝拉格苏木放牧方式基本上由定域(80年代前的嘎查级)游牧到浩特性半定居(80~90年代的放牧浩特级游动区域)游牧到牧户定居的(90年代中期后的网围栏限定区域草场分割轮牧)放牧方式变革,甚至有些地方变成半舍饲放牧。现在牧区围栏划区分割的轮牧制度,使放牧家畜的挑食时间变长的同时其采食践踏频度增大、食欲性游走时间和反复性距离拉长,增加践踏影响。由于放牧网围栏范围较小,牲畜头数的适量增加,畜群结构单一化发展和超载放牧现象,导致放牧网围栏草场的不同程度的退化。从1989~2016年的NDVI看一级NDVI值变小,即NDVI值减少了52.69%。研究区1989~2016年NDVI值呈现“V”字形变化,也就是1989~2000年NDVI逐渐降低,2000年达到最低值,而2003年又急剧升高,然后又逐渐减少。研究区NDVI值的变化也存在较大的空间差异,群落组成以克氏针茅+冷蒿变为克氏针茅+黄花蒿,主要优势种为克氏针茅、丝裂蒿(Artemisia adamsii),伴生种为羊草、阿氏旋花(Convolvulus ammannii),常见植物种为寸草苔、藜(Chenopo dium album Linn)、糙隐子草(Cleistogenes squarrosa)等,还有出现一些一年生植物占优势的年代(2003年)。(3)内蒙古那仁宝拉格苏木草场所取样地中的多年生草本植物优势比明显低于蒙古国纳兰苏木草场取样指标值。蒙古国纳兰苏木的四季游牧草场功能的多样性指数和优势度指数均高于我国那仁宝拉格苏木牧户定居放牧草场。多年生和一年生草本植物的生态幅较大,从而多年生与一年生植物之间的生态重叠明显而两处苏木均有差异;说明,不同放牧方式会导致草原植被群落退化,降低草原生态经济价值。综上所述,天然草地植被的持续性周转利用与游动自由放牧的家畜的选择性懫食和生态型生产有重要影响。不同的放牧方式下,由于家畜的生态行为性懫食践踏被改变,影响群落特征和生态系统组分的差异;为此选择合理的放牧方式有利于草原群落的自身周转和其优势种的稳定生长。
[Abstract]:From temperate grassland in semi arid area gradually expanded to semi humid area, is one of the largest terrestrial ecosystem types. It is not only the material basis of grassland on Mongolia plateau people's survival, heavy barrier is a desert grassland on Mongolia plateau and respond to regional climate change. The herdsman grazing to rely mainly on the use of grassland resources grazing, if reasonable, will directly or indirectly affect the structure and function of ecosystem in typical steppe region. Therefore, strengthening the grazing management is the core management of typical pasture. Grazing as grazing management system has been widespread concern and attention of domestic and foreign scholars and government departments. Therefore, this paper uses the theoretical research method combined with field survey, through the analysis of Mongolia's and North China region, hematoxylin hematoxylin Naran two identical natural Lagrange Background area as the study area, using NDVI and using the maximum synthesis method of dynamic monitoring and field sampling and testing data of 2016 grassland animal husbandry two hematoxylin NDVI based. Analysis of the effect of grazing on the transformation process of grassland community changes, the results are as follows: (1) Mongolia's hematoxylin grazing Nalan from nonlocal to local nomadic nomadic, at present mainly in the seasonal migration, with pasture grazing and seasonal swimming camp the sectional grazing grassland vegetation, have full recovery opportunities, reduced grazing livestock trampling pressure, but also fully embodies the coupling relationship between forage grassland and the proportion of NDVI and the structure of livestock diversity. But in recent years due to the increase in the number of livestock, livestock structure changes, reduce the area of grassland, leading to pasture by different trampling and degradation.1989~2011 The NDVI level of vegetation index is less, not much change; 2011~2016 between two NDVI values decreased 53.97%. community composition in Stipa krylovii + Artemisia frigida into Leymus chinensis and Stipa krylovii, wheatgrass community mixed, the main dominant species of Leymus chinensis (Leymus chinensis), s.krylovii (Stipa krylovii), as the companion species of Carex duriuscula (Carex duriuscula), S.grandis (Stipa grandis P.Smirn.) is a common species of Wheatgrass (Agropyron cristatum), Artemisia frigida (Artemisia FRIGIDA) (Kochia prostrate), Kochia prostrata (Ajania polyrrhizum), a plurality of onions. As well as increasing the annual plant (2) in Inner Mongolia. The Gulag grazing basically Compal hematoxylin by localized (GaZha level before 80s) to semi nomadic haute settled (grazing in the swimming area 80~90 super HO) to settle the nomadic herdsmen (fence in mid 90s after the regional segmentation of grassland grazing) Grazing patterns change, and even in some places become semi feeding grazing. Now under segmentation of the rotational grazing system in pastoral areas fence, the grazing time becomes longer and the food intake frequency increases the appetite of trampling, wandering time and repeated long distance, increased by trampling. Grazing fence range is small, the number of livestock amount increase the single herd structure development and overgrazing, resulting in degradation of different grazing pasture fence. See a NDVI from 1989~2016 NDVI value, NDVI value decreased by 52.69%. 1989~ in the study area in 2016 NDVI showed a "V" shape change, namely 1989~2000 year NDVI decreased gradually in 2000 the lowest, while in 2003 it increased sharply, and then decreased gradually. There are also large differences in the spatial variation of NDVI values in the study area, the community composition in Stipa krylovii + Artemisia into Stipa krylovii + Artemisia annua, the main dominant species of Stipa krylovii, mitogen (Artemisia adamsii), Artemisia associated species for Leymus chinensis, Agassiz Convolvulus (Convolvulus ammannii), is a common plant species of Carex duriuscula (Chenopo dium album Linn, Chenopodium album), c.squarrosa (Cleistogenes squarrosa), as well as some therophyta the advantage of the time (2003). (3) the Inner Mongolia Compal Rugby sampled in the grassland sappan perennial herbaceous plants were lower than those of pasture advantage sampling in Mongolia. Mongolia, Su mu in four seasons nomadic grassland Nalan sappan functional diversity index and dominance index were higher than that in China the Gulag herdsman settled by Compal grazing pasture of perennial and annual herbs. The ecological amplitude is large, and between ecological perennial and annual plants and two had obvious overlap, hematoxylin difference; different grazing will lead to grassland Vegetation degradation, decrease of grassland ecological economic value. To sum up, has an important influence and walk free grazing livestock food and ecological production by selective Zhi continuous turnover of natural grassland vegetation. Different grazing patterns, because livestock ecological behavior of Zhi food trampling is changed, the difference in the effects of community characteristics and ecological system this group; choose the reasonable grazing to grassland in its turnover and the stable growth of the species.

【学位授予单位】：内蒙古师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S812

【参考文献】