Changes in soil organic carbon lability along the altitudinal variations in three land use types of Meghalaya, India

Soil organic carbon (SOC) plays an important role in maintaining and improving soil fertility and quality, in addition to mitigating climate change. Understanding SOC spatial variability is fundamental for describing soil resources and predicting SOC. In this study, SOC content and SOC mass were estimated based on a soil survey of a small watershed in the Dan River, China. The spatial heterogeneity of SOC distribution and the impacts of land-use types, elevation, slope, and aspect on SOC were also assessed. Field sampling was carried out based on a 100 m by 100 m grid system overlaid on the topographic map of the study area, and samples were collected in three soil layers to a depth of 40 cm. In total, 222 sites were sampled and 629 soil samples were collected. The results showed that classical kriging could successfully interpolate SOC content in the watershed. Contents of SOC showed strong spatial heterogeneity based on the values of the coefficient of variation and the nugget ratio, and this was attributed largely to the type of land use. The range of the semi-variograms increased with increasing soil depth. The SOC content in the soil profile decreased as soil depth increased, and there were significant (P < 0.01) differences among the three soil layers. Land use had a great impact on the SOC content. ANOVA indicated that the spatial variation of SOC contents under different land use types was significant (P < 0.05). The SOC mass of different land-use types followed the order grassland > forestland > cropland. Mean SOC masses of grassland, forestland, and cropland at a depth of 0–40 cm were 5.87, 5.61, and 5.07 kg m–2, respectively. The spatial variation of SOC masses under different land-use types was significant (P < 0.05). ANOVA also showed significant (P < 0.05) impact of aspect on SOC mass in soil at 0–40 cm. Soil bulk density played an important role in the assessment of SOC mass. In conclusion, carbon in soils in the source area of the middle Dan River would increase with conversion from agricultural land to forest or grassland.

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Soil organic carbon and microbial community structure exhibit different responses to three land use types in the North China Plain

Acta Agriculturae Scandinavica Section B - Soil & Plant Science ◽

10.1080/09064710.2015.1011223 ◽

2015 ◽

Vol 65 (4) ◽

pp. 341-349 ◽

Cited By ~ 1

Author(s):

Guo Zhang ◽

Chunyan Zheng ◽

Yi Wang ◽

Yufei Li ◽

Ying Xin

Keyword(s):

Land Use ◽

Community Structure ◽

Microbial Community ◽

Organic Carbon ◽

Soil Organic Carbon ◽

North China Plain ◽

North China ◽

The North ◽

The North China Plain ◽

Land Use Types

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Effects of climate change and land management on soil organic carbon dynamics and carbon leaching in northwestern Europe

Biogeosciences ◽

10.5194/bg-13-1519-2016 ◽

2016 ◽

Vol 13 (5) ◽

pp. 1519-1536 ◽

Cited By ~ 14

Author(s):

Maria Stergiadi ◽

Marcel van der Perk ◽

Ton C. M. de Nijs ◽

Marc F. P. Bierkens

Keyword(s):

Climate Change ◽

Land Use ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Land Management ◽

Arable Land ◽

Climate Change Scenarios ◽

Century Model ◽

Precipitation Effect ◽

Land Use Types

Abstract. Climate change and land management practices are projected to significantly affect soil organic carbon (SOC) dynamics and dissolved organic carbon (DOC) leaching from soils. In this modelling study, we adopted the Century model to simulate past (1906–2012), present, and future (2013–2100) SOC and DOC levels for sandy and loamy soils typical of northwestern European conditions under three land use types (forest, grassland, and arable land) and several future scenarios addressing climate change and land management change. To our knowledge, this is the first time that the Century model has been applied to assess the effects of climate change and land management on DOC concentrations and leaching rates, which, in combination with SOC, play a major role in metal transport through soil. The simulated current SOC levels were generally in line with the observed values for the different kinds of soil and land use types. The climate change scenarios result in a decrease in both SOC and DOC for the agricultural systems, whereas for the forest systems, SOC is projected to slightly increase and DOC to decrease. An analysis of the sole effects of changes in temperature and changes in precipitation showed that, for SOC, the temperature effect predominates over the precipitation effect, whereas for DOC the precipitation effect is more prominent. A reduction in the application rates of fertilisers under the land management scenario leads to a decrease in the SOC stocks and the DOC leaching rates for the arable land systems, but it has a negligible effect on SOC and DOC levels for the grassland systems. Our study demonstrated the ability of the Century model to simulate climate change and agricultural management effects on SOC dynamics and DOC leaching, providing a robust tool for the assessment of carbon sequestration and the implications for contaminant transport in soils.

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Estimating Soil Organic Carbon Under Different Land-Use Types in Australia’s Northern Grains Region Using Mid-Infrared Spectroscopy

Proceedings ◽

10.3390/proceedings2019036141 ◽

2020 ◽

Vol 36 (1) ◽

pp. 141

Author(s):

Alwyn Williams ◽

Ryan Farquharson ◽

David Lawrence ◽

Jeff Baldock ◽

Mike Bell

Keyword(s):

Land Use ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Native Vegetation ◽

Land Use Type ◽

Short Term ◽

Mid Infrared ◽

Land Use Types ◽

Soc Fractions

Land-use type is known to affect levels of soil organic carbon (SOC). However, the degree to which SOC is affected by land-use type over the short—(<10-years) and long—(≥10-years) term remains relatively uncertain. Moreover, there is limited data on the distribution of SOC across particulate (POC), humus (HOC) and resistant (ROC) fractions, and the responses of these fractions to land-use. Using mid-infrared spectroscopy (MIR) coupled with partial least squares regression (PLSR) algorithms generated from the Australian Soil Carbon Research Program (SCaRP), soil organic carbon (TOC, POC, HOC and ROC) was estimated across 280 paired samples across Australia’s Northern Grains Regions. Our analysis covered five land-use types: remnant native vegetation, long-term pasture (≥10-years), short-term pasture (<10-years), short-term cropping (<10-years) and long-term cropping (≥10-years). All land-use types except long-term pasture generated significant declines across all SOC fractions compared with native vegetation. Long-term cropping resulted in the greatest declines, with an average decrease of 6.25 g TOC/kg soil relative to native vegetation. Long-term cropping also reduced POC (−0.71 g/kg) and HOC (−3.19 g/kg) below that of short-term cropping. In addition, the ROC fraction responded to land-use type, with native vegetation and long-term pasture maintaining greater ROC compared with other land-use types. The results demonstrate substantial reductions across all SOC fractions with long-term cropping. The ability of long-term pastures to maintain levels of SOC similar to that of native vegetation indicates the importance of limiting soil disturbance and maintaining more continuous living plant cover within cropping systems.

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