Vertical variations of soil carbon under different land uses in a karst critical zone observatory (CZO), SW China

نویسندگان

چکیده

Soil is a key carbon reservoir balancing global budget and regulating climate change. Barren soils in karst zones have weak capacity for soil water conservation are readily erodible, making the biogeochemical processes within potentially rapid complex. To explore vertical variation of under conditions its response to land-use change, this study investigated concentrations isotopic compositions both organic inorganic (SOC SIC) different depths four types typical region, SW China. Results show that as depth increases, SOC decrease, δ13C ratios (from −27.3‰ −19.4‰) increase 0–20 cm but decrease at below 20 cm. The fresh mostly sequestered cycled topsoil subject controls than subsoil. turnover rate does not directly co-vary with fractionation among land uses. Long-term cultivation causes loss from soils, which can be alleviated or even partially restored after farming cessation. By contrast, SIC represents < 10% total carbon. heterogeneity direct influence biological factors on weaker relative SOC. low −20.4‰ −3.0‰) indicate there intense dissolution reprecipitation pedogenic carbonate soil, especially upper cultivated layers. These results highlight labile susceptible change zones, need considered estimating sink role variable temporal scales.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Soil Respiration under Different Land Uses in Eastern China

Land-use change has a crucial influence on soil respiration, which further affects soil nutrient availability and carbon stock. We monitored soil respiration rates under different land-use types (tea gardens with three production levels, adjacent woodland, and a vegetable field) in Eastern China at weekly intervals over a year using the dynamic closed chamber method. The relationship between so...

متن کامل

Vertical Distribution of Bacterivorous Nematodes under Different Land Uses.

The vertical distribution of dominant genera of bacterivorous nematodes to 150-cm depth in an aquic brown soil was compared after 14 years of four contrasting land uses, i.e., cropland-rice (CR), cropland-maize (CM), abandoned cropland (AC), and woodland (WL). The study was conducted at the Shenyang Experimental Station of Ecology, a Chinese Ecosystem Research Network (CERN) site in Northeast C...

متن کامل

The importance of non-carbonate mineral weathering as a soil formation mechanism within a karst weathering profile in the SPECTRA Critical Zone Observatory, Guizhou Province, China

Soil degradation, including rocky desertification, of the karst regions in China is severe. Karst landscapes are especially sensitive to soil degradation as carbonate rocks are nutrient-poor and easily eroded. Understanding the balance between soil formation and soil erosion is critical for long-term soil sustainability, yet little is known about the initial soil forming processes on karst terr...

متن کامل

Soil aggregate mediates the impacts of land uses on organic carbon, total nitrogen, and microbial activity in a Karst ecosystem

Understanding the effect of land use on soil carbon, nitrogen, and microbial activity associated with aggregates is critical for thorough comprehension of the C and N dynamics of karst landscapes/ecosystems. We monitored soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC), and Cmic: Corg ratio in large macro- (>2 mm), small macro- (0.25-2 mm), and micro- (0.053-0.25 m...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Geoderma

سال: 2022

ISSN: ['0016-7061', '1872-6259']

DOI: https://doi.org/10.1016/j.geoderma.2022.115741