Carbonate weathering-related carbon sink fluxes under different land uses: A case study from the Shawan Simulation Test Site, Puding, Southwest China

Natural and Anthropogenic Driving Forces of Carbonate Weathering and the Related Carbon Sink Flux: A Model Comparison Study at Global Scale

“…The total runoff changes due to cropland expansion and urbanization are +25 mm and +56 mm in cold climates and +75 mm and +169 mm in tropics. The above model experiments confirm our results from the field test site in southwest China (Zeng et al., 2017). Compared with natural land cover, bare rock generates the lowest CCSF while cropland produces the highest.…”

Sensitivity of the global carbonate weathering carbon-sink flux to climate and land-use changes

“…For a long time human activities were not considered in global carbonate weathering models. However, recent studies 4,11,17 have found that land use does play a significant role in CCSF control and should be considered in carbon-sink models. On the one hand, consideration of land use can help us to explain why similar climate conditions present highly scattered [HCO 3 − ] eq distributions in different datasets 6,15 .…”

“…In addition, in order to estimate the hydrological changes of other land-cover/land-use types in the LHU dataset, we additionally introduce three extended models (for crop, non forest, and urban) that are based on the standard function given by Zhang et al 37 . Our extension functions are based on a three-year water balance study in a karst simulation test site that detects the water yields of five different land uses in karst terrain 17 . The final modified model can be expressed as:where ET sum (mm) is the total annual evapotranspiration, f , g , n , c , and u are the ratios of forest, grass, non forest, crop, and urban cover in e ach pixel, respectively ( f + g + n + c + u = 1), and ET f , ET g , ET n , ETc, and ET u (mm) are the corresponding annual evapotranspiration from different land uses.…”

“…Previous work has highlighted the diverse geochemical, climatic and ecological factors that influence both R and DIC, and thus the CCSF variations, including (amongst others) surface temperature 6 , precipitation and runoff 11,12 , net primary production of ecosystem and soil CO 2 6,13 , carbonate lithologies 12 , atmospheric CO 2 concentration 14 , soil water content 15 and land-use patterns, and practices 4,16,17 . In natural environments, these factors are tightly interwoven and controlled by climate and land cover 17,18 . Recently, studies on different spatial scales have reported that climate perturbations and human interventions have dramatically changed CCSF over the past few decades.…”

“…In particular, to our knowledge no studies have considered the impacts of long-term land-use change on CCSF fluctuations at the global scale. In many areas with intensive human intervention, land-use changes have altered the CCSF by changing the runoff patterns and affecting the soil p CO 2 through changing, amongst others, the productivity and soil properties 17 , etc.…”