Sensitivity analysis and calibration of a soil carbon model (SoilGen2) in two contrasting loess forest soils
نویسندگان
چکیده
To accurately estimate past terrestrial carbon pools is the key to understanding the global carbon cycle and its relationship with the climate system. SoilGen2 is a useful tool to obtain aspects of soil properties (including carbon content) by simulating soil formation processes; thus it offers an opportunity for both past soil carbon pool reconstruction and future carbon pool prediction. In order to apply it to various environmental conditions, parameters related to carbon cycle process in SoilGen2 are calibrated based on six soil pedons from two typical loess deposition regions (Belgium and China). Sensitivity analysis using the Morris method shows that decomposition rate of humus (kHUM), fraction of incoming plant material as leaf litter (frecto) and decomposition rate of resistant plant material (kRPM) are the three most sensitive parameters that would cause the greatest uncertainty in simulated change of soil organic carbon in both regions. According to the principle of minimizing the difference between simulated and measured organic carbon by comparing quality indices, the suited values of kHUM, frecto and kRPM in the model are deduced step by step and validated for independent soil pedons. The difference of calibrated parameters between Belgium and China may be attributed to their different vegetation types and climate conditions. This calibrated model allows more accurate simulation of carbon change in the whole pedon and has potential for future modeling of carbon cycle over long timescales.
منابع مشابه
Geochemical characterization of the forest loess soils along a precipitation gradient in Northern Iran
Introduction: The loess-paleosol sequences in Northern Iran are important archives represent several cycles of Quaternary climate change and can be used to complete the information gap on loess between Europe and central Asia. Loess geochemistry reflects paleoweathering conditions and it can be used to determine the nature and provenance of loess deposits. In the Caspian Lowlands, a pronounced...
متن کاملEffect of Land Use on the Carbon Stock and Soil Quality Attributes in Loess Derived Soils in Agh-Su Watershed, Golestan Province, Iran
متن کامل
Effect of a long-term cultivation and crop rotations on organic carbon in loess derived soils of Golestan Province, Northern Iran
The effects of 34 years cultivation on organic carbon content of the loess derived soils were studied in Golestan province, northern Iran. Soil organic carbon (SOC) showed significant decrease in most of cases. The minimum and maximum SOC decreases were 4 and 51.14 Mg C ha-1/30 cm for 34 years. In a few cases there was an increase in SOC up to 16.93 Mg C ha-1/30 cm over the period of 34 years i...
متن کاملمیکرومورفولوژی تحول خاک در کاربریهای مختلف در اراضی لسی منطقه آق سو، استان گلستان
In order to study the effects of different land uses on soil development, a loess hillslope was selected in Agh-Su area, eastern Golestan Province. Six profiles in four land uses including pasture, Quercuse natural forest, Cupressus artificial forest and a cultivated land, were dug and studied. Samples from different horizons were collected for physico-chemical and microscopic analyses. Importa...
متن کاملThe Effect of Land Use Change on Transformation of Relief and Modification of Soils in Undulating Loess Area of East Poland
The change of primary forest areas into arable land involves the transformation of relief and modification of soils. In this study, we hypothesized that relatively flat loess area was largely transformed after the change of land use due to erosion. The modifications in soil pedons and distribution of soil properties were studied after 185 years of arable land use. Structure of pedons and solum ...
متن کامل