Iranian Journal of Applied Ecology (Mar 2015)
Evaluating Structural and Functional Characteristics of Various Ecological Patches in Different Range Conditions (Case Study: Semi -Steppe Rangeland of Aghche-Isfahan)
Abstract
Rangeland condition assessment plays an important role in determining range health and applying appropriate management programs. This study aimed to evaluate the structure and function of a semi-steppe rangeland using Landscape Function Analysis technique (LFA) in different land conditions in western Isfahan province, Iran. For this purpose, 4, 3 and 7 sites in different rangeland condition classes including very poor, poor, and moderate were selected respectively. In each site, a 30-meter transect was established and all kinds of patches and inter patches were identified and their lengths and widths were recorded. Also, in each ecological patch, 11 indicators of soil surface characteristics with three replications were measured, and their status was scored according to LFA method. The functionality indices of all the sites including soil stability, infiltration and nutrient cycling were measured. According to the statistical analysis results, most of the structural characteristics (number of patches, patch length, patch area index, landscape organization index) and functional indices (infiltration, stability and nutrient cycling status) varied significantly (α= 5%) between rangeland sites with moderate and very poor condition. The changes of these structural and functional characteristics were not significant between range sites with moderate and poor, and also poor and very poor range conditions. According to the findings of this study, patch types' functionalities did not vary significantly in both rangeland sites with moderate and very poor conditions. The nutrient cycling index in patches formed by ‘forb, shrub and grass’ with poor range condition was significantly more than ‘forb’ and ‘grass’ patches. The study of range site functionality can assist managers in identifying possible ecological thresholds and prioritizing the sub-catchments and vegetation types for implementing range improvement practices.
