Discipline: Ecology Environmental and Earth Sciences
Subcategory: Climate Change
Alisha M. Bailey - Alabama A&M University
Co-Author(s): Elica M. Moss, Alabama A&M University Zengxin Zhang, Nanjing Forestry University, Jiangsu Province
The Poyang Lake is a major freshwater lake in the Jiangsu Province in China with a subtropical climate zone consisting of high humidity along with any major hydrological changes can cause variations along the river basins surrounding the lake. There are five (5) major river basins that surround the Poyang Lake including: Fuhe, Ganjiang, Xinjiang, Roahe, and Xiushui. This research focuses on two (2) of the five (5) basins: Ganjiang and Xinjiang Rivers. The vegetation along the Poyang Lake affect the annual and seasonal disparities of streamflow. Vegetation amounts around the Poyang Lake based on the season and can be traced by calculating the Normalized Difference Vegetation Index (NDVI) amount. NDVI is a numerical amount without units of live vegetation, water, or land coverage within a particular region. This research discusses the temporal and spatial variabilities of NDVI in the Poyang Lake River basins based on data from 1982 to 2013. This study also looks to reveal the relationship between the seasonal and annual streamflow and NDVI on a large scale. Statistical methods were used to show the simple linear regression and t-test while ArcGIS 10.2 and Origin Pro 8.0 were used to show the spatial interpolation and proportional relationships between NDVI and streamflow. Various conditions affect streamflow in and out of the river basin leading to a change in vegetation values. The results of the seasonal NDVI data indicate that: (1) NDVI was the lowest around both the Ganjiang and Xinjiang River basins during the spring and winter season. The NDVI values were the highest during the summer and autumn seasons with higher peaks of vegetation in the Xinjiang basin due to it being a smaller river basin; (2) the streamflow and NDVI values in the Ganjiang and Xinjiang River basins have an inverse relationship; when the streamflow increases then the NDVI values decrease. This research helps to reveal the type of relationships either positive or negative that streamflow plays on vegetation. The usefulness of the results can help to later reveal why specific hydrological changes have such a huge impact on streamflow. Future work includes focusing on how vegetation can be affected by human implications, the building of dams as well as streamflow.
References: Wang, J., Rich, P., & Price, K. (2003). Temporal responses of NDVI to precipitation and temperature in the central Great Plains, USA. International Journal of Remote Sensing, 24(11), 2345-2364.
Xu, C.-Y. (2001). Statistical analysis of a conceptual water balance model, methodology and case study. Water Resources Management, 15, 75-92.
Ye, X., Zhang, Q., Liu, J., Li, X., & Xu, C.-y. (2013). Distinguishing the relative impacts of climate change and human activities on variation of streamflow in the Poyang Lake catchment, China. Journal of Hydrology, 494, 83-95.
Zhang, Z., Zhang, Q., Xu, C.-Y., Liu, C.-L., & Jiang, T. (2009). Atmospheric moisture budget and floods in the Yangtze River Basin, China. Theoretical and Applied Climatology, 95, 331-340.
Funder Acknowledgement(s): I would like to thank graduate students: Huang Yuhan, Jiang Shanshan, Qiu Jin, Du Wei for their help in compiling the data. Funding for this project was provided by CREST Grant No. HRD-1036600, USDA National Institute of Food and Agriculture under Grant No. 2009-51160-05462, and Grant No. 2013-38821-21250.
Faculty Advisor: Elica M. Moss, email@example.com
Role: The part of this research that I completed was constructing the maps for the different river basins in ARCGIS 10.2 and creating graphs in Origin Pro 8.0. I completed the methods section of the research showing the linear regression and test. I completed a research paper, poster, and power point for the Research Experience for Graduate (REUG) program and presented at the end of the program.