【作者】 邹梅；

【导师】 李凤民； 武昕原；

【作者基本信息】 兰州大学 ， 生态学， 2011， 硕士

【摘要】 黄土高原半干旱丘陵区由于自然条件和放牧的影响,在坡地自然植被上放牧所形成的斑状植被是一种独特的植被景观格局——羊道斑状植被景观格局。本文从景观生态学和放牧生态学的角度探讨了其形成过程,并进行了计算机模拟。本文通过拍照取样,实地测量以及地理系统软件ARCGIS和ERDAS的处理,获得羊道景观的覆盖类型与微地形数据,从这些数据中试图找出了羊道景观格局的基本特征：1)羊道景观是羊道和非羊道交替出现的网络结构,这种网络把该景观分成了多个不规则长条状的斑块。羊道上没有植物,非羊道的上部植物较多,其中以有较强抗侵蚀能力的多年生冷蒿居多,下部结皮较多。2)有植物地方的表面DEM (Digital Elevation Model,数字高程模型)较没植物地方高,最大高度差为50cm左右。3)羊道宽度大部分都小于20cm,平均约16cm；非羊道的宽度相差较大,平均约63cm。4)羊道的土壤紧实度较非羊道的土壤紧实度大。5)羊道的坡度大部分都低于20。,非羊道部分的坡度在20。到80。不等,羊道坡度明显低于非羊道的坡度。本文分析了羊道景观的形成原理,假设羊道景观的形成过程,并借助元胞自动机进行模拟。考虑到植被对微地形变化的影响和植被与微地形对羊道路径选择的影响,设定土壤侵蚀规则和羊道路径选择规则来构造模型,分别模拟微地形的变化和羊道路径的形成。模拟结果表明,土壤紧实度、多年生植物、微地形、偏离位置和采食搜索范围是羊道路径形成的影响因素,利用这些因素能有效的模拟羊道形成。更多还原

【Abstract】 Special ecological environment and high grazing press make landscape of semi-arid hilly loess plateau a unique one---- goat road landscape. Based on method and theory from landscape ecology and grazing ecology, we have a preliminary analysis and simulate about goat road landscape.According to the camera sampled, field measurements and geographic software like ARCGIS and ERDAS processing, we got the data about cover types and micro-topographic of goat road landscape. Through these data, we find out some features of goat road landscape:1) goat road landscape is alternated with goat road and non-goat road, goat road form a network structure, such network divided plants into several irregular patches. There are few plants on goat road, and more plants on the up part of non-goat road, and most of these plants are perennial Artemisia frigide, which has strong anti-erosion ability, the other part of non-goat road are crust.2) the grids with plant have higher DEM (Digital Elevation Model) value than the grids with nothing. The difference is between Ocm and 50cm.3) the width of most goat road are less than 20cm, the average width is 16cm; compare to that, the average width in non-goat road is 63cm.4) the soil compaction of goat road are generally larger than non-goat road.5) the slope of goat road is less than 20°, it is significantly lower than non-goat road.This paper analyzes the formation theory of the goat road landscape, assumes the formation process, and use cellular automata model to simulate it’s forming process. Taking into account the effect of vegetation changes on the micro-topography and vegetation and micro-topography effects on goat road selection, we set the rules about soil erosion and goat road selection to simulate micro-topography changes and the formation of goat road. Results show that the soil compactness, perennials, micro-topography, deviation position and the search range are main factors of goat road formation, these factors were better able to simulate the goat road.更多还原