An Algorithm for Gross Primary Production (GPP) and Net Ecosystem Production (NEP) Estimations in the Midstream of the Heihe River Basin, China

Abstract

An accurate estimation of carbon fluxes is very important in carbon cycle studies. A remote sensing based gross primary production (GPP) and net ecosystem production (NEP) algorithm, RS-CFLUX, was presented in this work. The RS-CFLUX model can correctly simulate the seasonal dynamics and quantities of carbon fluxes at both stations, using photosynthetically active radiation (PAR), land surface temperature (LST), normalized difference water index (NDWI) and enhanced vegetation index (EVI) as input. RS-CFLUX model were sensitive to maximum light use efficiency, respiration at reference temperature, activation energy parameter of respiration.

Spatio-Temporal Variation and Impact Factors for Vegetation Carbon Sequestration and Oxygen Production Based on Rocky Desertification Control in the Karst Region of Southwest China

“…First, spatial scale is an important factor, and a multi-scale assessment of CSOP is necessary. The spatial scale at which vegetation type is measured significantly influences both the ecosystem service extent and its valuation [5,32,35]. Karst ecosystem areas are considerably fragile and heterogeneous [11], and the spatial scale needs to be taken into account in future evaluation of CSOP of this or similar regions.…”

“…The estimated results have some degree of uncertainty because of the complexity and dynamics of the ecosystems [5,[32][33][34]. Several factors affected the accuracy of CSOP estimation at the regional scale.…”

“…Consequently, the MODIS NDVI product has been applied to quantify vegetation cover and green biomass. Numerous studies have noted the effects of vegetation dynamics and climatic factors on vegetation in different ecosystems [5,6], and these studies showed that vegetation conditions were positively correlated with precipitation in most relatively dry areas, but negatively correlated in relatively humid areas [7,8].…”

“…Moderate-resolution imaging spectroradiometry (MODIS) is widely used to monitor the spatial and temporal variation of ecosystem conditions because of its frequent and global coverage [4,5]. The normalized difference vegetation index (NDVI) is calculated as the difference between the reflectance in the red band (610-680 nm) and near infrared band (780-890 nm).…”

The Greenness of Major Shrublands in China Increased from 2001 to 2013

“…EVI has been widely used to monitor and measure vegetation growth status [29,30], primary productivity [31][32][33][34][35][36][37], evapotranspiration [38], and plant phenology changes [39].…”