Eco-Environment Evaluation of Grassland Based on Remote Sensing Ecological Index: A Case in Hulunbuir Area, China

Jiawei Hui,Zhongke Bai,Baoying Ye

doi:10.4236/jcc.2021.96012

Abstract

This research is based on Landsat5 TM, Landsat8 OLI/TIRS remote sensing data using RSEI model to analyze and monitor the ecological environment and its temporal and spatial changes in the forest-grass transition zone in Northeast China from 2004 to 2019. The change characteristics of the ecological environment of different types of land cover types are monitored by RSEI method, and the response of different land cover types to natural factors such as precipitation and temperature is analyzed at the same time. The distribution of RSEI in the study area presents the characteristics of high in the east and low in the west. The eastern mountainous area is densely covered with woodland, which is the area with the best ecological environment quality in the study area. The grassland in the western plain and the saline-alkali land around the river are the areas with poor ecological environment in the study area. Climate, precipitation, topography and other natural elements work together to form the quality of the ecological environment in the study area roughly bounded by 120?E. In years with poor natural conditions, this dividing line will have a clear eastward shifting trend, especially in the northern part of the study area. The spatial distribution of RSEI in the study area has a high degree of spatial autocorrelation, and Global Moran’s I has been above 0.8 over the years. In terms of temporal changes in ecological conditions, the ecological environment in the study area was basically stable from 2004 to 2008, with a slight deterioration; it improved significantly from 2008 to 2011; however, it deteriorated significantly from 2011 to 2019. According to the results of partial correlation analysis, the ecological environment of the former is highly correlated with natural elements such as climate and precipitation, while the latter is mainly affected by human factors.

Highlights

Grassland resources are the largest ecological system on the land of China, and play an important role and value in developing animal husbandry, protecting biodiversity, maintaining water and soil, and maintaining ecological balance
The change characteristics of the ecological environment of different types of land cover types are monitored by Remote Sensing Ecological Index (RSEI) method, and the response of different land cover types to natural factors such as precipitation and temperature is analyzed at the same time
The commonly used methods for grassland ecological evaluation and monitoring include Normalized Difference Vegetation Index (NDVI) change monitoring based on remote sensing data [10], vegetation change monitoring based on drone data [11], and comprehensive evaluation based on multiple data sources [12] and so on

Summary

Introduction

Grassland resources are the largest ecological system on the land of China, and play an important role and value in developing animal husbandry, protecting biodiversity, maintaining water and soil, and maintaining ecological balance. The ecological quality of China’s grassland is facing serious risks of degradation and desertification [1] [2] [3]. Many studies have shown that overgrazing has become one of the main causes of grassland degradation [4] [5] [6] [7] [8]. From 2000 to 2012, the total amount of livestock in Hulunbuir grassland and the overload rate of livestock continued to rise, and the overload rate of livestock in 2012 exceeded 30% [9]. The commonly used methods for grassland ecological evaluation and monitoring include NDVI change monitoring based on remote sensing data [10], vegetation change monitoring based on drone data [11], and comprehensive evaluation based on multiple data sources [12] and so on

Methods

Results

Conclusion