Duan, Jiaming (2020). Influence of Land-use Change and Agricultural Practices on Water, Carbon, Energy Fluxes. Master’s thesis, Texas A&M University. https://hdl.handle.net/1969.1/192258.
The expansion of the urban area and agriculture field in the past centuries converted many natural prairies to crop fields and residence places, which brought many problems that influenced the interactions between biosphere and atmosphere. However, the effects caused by the land-use change were various at different locations and sometimes showed conflict results. In this study, we concentrated on agriculture development in Texas Blackland Prairies to investigate the regional influence of land-use change and agriculture practices on the carbon flux, evapotranspiration, and energy transformation. We expected (1) to estimate total carbon uptake water use efficiency (WUE), and total corn yields under different ecosystems and management practices, (2) to compare the gas fluxes, energy fluxes and micrometeorology in observation sites, (3) to determine the effect of agriculture strategies and land-use change on gas fluxes and energy partitioning. We collected flux data through the Eddy Covariance system in the native prairie (RFPr), conventional field (RFTA), and aspirational field (RFAA) at different biophysical statuses and monitored the plant growth with PhenoCam. The total carbon uptake was 1062 g/m2,1388 g/m2, and 2166 g/m2 in RFPr, RFAA, and RFTA respectively. The total corn yield of the conventional field was higher than the aspirational field as well as the WUE. The RFPr and RFTA showed subtle differences in WUE, soil moisture and energy partitioning which indicated the land use change without disturbance from other agriculture practices might not influence the biosphere-atmosphere interactions. But the more significant difference between RFTA and RFAA in carbon, water and energy fluxes demonstrated the weed control might be more influential than the plant cover change.