Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin
Terrestrial vegetation dynamics are closely influenced by both hydrological process and climate change. This study investigated the relationships between vegetation pattern and hydro-meteorological elements. The joint entropy method was employed to evaluate the dependence between the normalized diff...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-09-01
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| Series: | Entropy |
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| Online Access: | https://www.mdpi.com/1099-4300/19/9/502 |
| _version_ | 1828153926789103616 |
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| author | Gengxi Zhang Xiaoling Su Vijay P. Singh Olusola O. Ayantobo |
| author_facet | Gengxi Zhang Xiaoling Su Vijay P. Singh Olusola O. Ayantobo |
| author_sort | Gengxi Zhang |
| collection | DOAJ |
| description | Terrestrial vegetation dynamics are closely influenced by both hydrological process and climate change. This study investigated the relationships between vegetation pattern and hydro-meteorological elements. The joint entropy method was employed to evaluate the dependence between the normalized difference vegetation index (NDVI) and coupled variables in the middle reaches of the Hei River basin. Based on the spatial distribution of mutual information, the whole study area was divided into five sub-regions. In each sub-region, nested statistical models were applied to model the NDVI on the grid and regional scales, respectively. Results showed that the annual average NDVI increased at a rate of 0.005/a over the past 11 years. In the desert regions, the NDVI increased significantly with an increase in precipitation and temperature, and a high accuracy of retrieving NDVI model was obtained by coupling precipitation and temperature, especially in sub-region I. In the oasis regions, groundwater was also an important factor driving vegetation growth, and the rise of the groundwater level contributed to the growth of vegetation. However, the relationship was weaker in artificial oasis regions (sub-region III and sub-region V) due to the influence of human activities such as irrigation. The overall correlation coefficient between the observed NDVI and modeled NDVI was observed to be 0.97. The outcomes of this study are suitable for ecosystem monitoring, especially in the realm of climate change. Further studies are necessary and should consider more factors, such as runoff and irrigation. |
| first_indexed | 2024-04-11T22:31:45Z |
| format | Article |
| id | doaj.art-239b4cf31991409085ef7a67a6eb7a17 |
| institution | Directory Open Access Journal |
| issn | 1099-4300 |
| language | English |
| last_indexed | 2024-04-11T22:31:45Z |
| publishDate | 2017-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Entropy |
| spelling | doaj.art-239b4cf31991409085ef7a67a6eb7a172022-12-22T03:59:20ZengMDPI AGEntropy1099-43002017-09-0119950210.3390/e19090502e19090502Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River BasinGengxi Zhang0Xiaoling Su1Vijay P. Singh2Olusola O. Ayantobo3College of Water Resources and Architectural Engineering, Northwest A & F University, Yangling 712100, ChinaCollege of Water Resources and Architectural Engineering, Northwest A & F University, Yangling 712100, ChinaDepartment of Biological & Agricultural Engineering and Zachry Department of Civil Engineering, Texas A&M University, 2117 TAMU, College Station, TX 77843, USACollege of Water Resources and Architectural Engineering, Northwest A & F University, Yangling 712100, ChinaTerrestrial vegetation dynamics are closely influenced by both hydrological process and climate change. This study investigated the relationships between vegetation pattern and hydro-meteorological elements. The joint entropy method was employed to evaluate the dependence between the normalized difference vegetation index (NDVI) and coupled variables in the middle reaches of the Hei River basin. Based on the spatial distribution of mutual information, the whole study area was divided into five sub-regions. In each sub-region, nested statistical models were applied to model the NDVI on the grid and regional scales, respectively. Results showed that the annual average NDVI increased at a rate of 0.005/a over the past 11 years. In the desert regions, the NDVI increased significantly with an increase in precipitation and temperature, and a high accuracy of retrieving NDVI model was obtained by coupling precipitation and temperature, especially in sub-region I. In the oasis regions, groundwater was also an important factor driving vegetation growth, and the rise of the groundwater level contributed to the growth of vegetation. However, the relationship was weaker in artificial oasis regions (sub-region III and sub-region V) due to the influence of human activities such as irrigation. The overall correlation coefficient between the observed NDVI and modeled NDVI was observed to be 0.97. The outcomes of this study are suitable for ecosystem monitoring, especially in the realm of climate change. Further studies are necessary and should consider more factors, such as runoff and irrigation.https://www.mdpi.com/1099-4300/19/9/502joint entropyNDVItemperatureprecipitationgroundwater depthHei River basin |
| spellingShingle | Gengxi Zhang Xiaoling Su Vijay P. Singh Olusola O. Ayantobo Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin Entropy joint entropy NDVI temperature precipitation groundwater depth Hei River basin |
| title | Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin |
| title_full | Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin |
| title_fullStr | Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin |
| title_full_unstemmed | Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin |
| title_short | Modeling NDVI Using Joint Entropy Method Considering Hydro-Meteorological Driving Factors in the Middle Reaches of Hei River Basin |
| title_sort | modeling ndvi using joint entropy method considering hydro meteorological driving factors in the middle reaches of hei river basin |
| topic | joint entropy NDVI temperature precipitation groundwater depth Hei River basin |
| url | https://www.mdpi.com/1099-4300/19/9/502 |
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