Rice paddy soils are a quantitatively important carbon store according to a global synthesis

AbstractRice paddies account for ~9% or the world’s cropland area and are characterized by environmental conditions promoting soil organic carbon storage, methane emissions and to a lesser extent nitrous oxide emissions. Here, we synthesize data from 612 sites across 51 countries to estimate global carbon stocks in paddy soils and determine the main factors affecting paddy soil carbon storage. Paddy soils (0–100 cm) contain 18 Pg carbon worldwide. Paddy soil carbon stocks decrease with increasing mean annual temperature and soil pH, whereas mean annual precipitation and clay content had minor impacts. Meta-analysis shows that paddy soil carbon stocks can be increased through several management practices. However, greenhouse gas mitigation through paddy soil carbon storage is generally outweighed by increases in methane and nitrous oxide emissions. Our results emphasize the key role of paddies in the global carbon cycle, and the importance of paddy management in minimizing anthropogenic greenhouse gas emissions.

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Modelling soil carbon stocks in semi-natural and agro-ecosystems – quantifying national scale impacts of the Anthropocene

10.5194/egusphere-egu2020-18355 ◽

2020 ◽

Author(s):

Victoria Janes-Bassett ◽

Jessica Davies ◽

Richard Bassett ◽

Dmitry Yumashev ◽

Ed Rowe ◽

...

Keyword(s):

Land Use ◽

Nutrient Cycling ◽

Soil Carbon ◽

Carbon Storage ◽

Management Practices ◽

Carbon Stocks ◽

Soil Carbon Storage ◽

National Scale ◽

Soil Carbon Stocks

Throughout the Anthropocene, the conversion of land to agriculture and atmospheric deposition of nitrogen have resulted in significant changes to biogeochemical cycling, including soil carbon stocks. Quantifying these changes is complex due to a number of influential factors (including climate, land use management, soil type) and their interactions. As the largest terrestrial store of carbon, soils are a key component in climate regulation. In addition, soil carbon storage contributes to numerous ecosystem services including food provision. It is therefore imperative that we understand changes to soil carbon stocks, and provide effective strategies for their future management.Modelling soil systems provides a means to estimate changes to soil carbon stocks. Due to linkages between the carbon cycle and other major nutrient cycles (notably nitrogen and phosphorus which often limit the productivity of ecosystems), models of integrated nutrient cycling are required to understand the response of the carbon cycle to global pressures. Simulating the impacts of land use changes requires capacity to model both semi-natural and intensive agricultural systems.In this study, we have developed an integrated carbon-nitrogen-phosphorus model of semi-natural systems to include representation of both arable and grassland systems, and a range of agricultural management practices. The model is applicable to large spatial scales, as it uses readily available input data and does not require site-specific calibration. &#160;After being validated both spatially and temporally using data from long-term experimental sites across Northern-Europe, the model was applied at a national scale throughout the United Kingdom to assess the impacts of land use change and management practices during the last two centuries. Results indicate a decrease in soil carbon in areas of agricultural expansion, yet in areas of semi-natural land use, atmospheric deposition of nitrogen has resulted in increased net primary productivity and subsequently soil carbon. The results demonstrate anthropogenic impacts on long-term nutrient cycling and soil carbon storage, and the importance of integrated nutrient cycling within models.

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Soil carbon stocks vary predictably with altitude in tropical forests: Implications for soil carbon storage

Geoderma ◽

10.1016/j.geoderma.2013.04.005 ◽

2013 ◽

Vol 204-205 ◽

pp. 59-67 ◽

Cited By ~ 51

Author(s):

Wouter I.J. Dieleman ◽

Michelle Venter ◽

Anurag Ramachandra ◽

Andrew K. Krockenberger ◽

Michael I. Bird

Keyword(s):

Soil Carbon ◽

Carbon Storage ◽

Tropical Forests ◽

Carbon Stocks ◽

Soil Carbon Storage ◽

Soil Carbon Stocks

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The southern Brazilian grassland biome: soil carbon stocks, fluxes of greenhouse gases and some options for mitigation

Brazilian Journal of Biology ◽

10.1590/s1519-69842012000400006 ◽

2012 ◽

Vol 72 (3 suppl) ◽

pp. 673-681 ◽

Cited By ~ 12

Author(s):

VD Pillar ◽

CG Tornquist ◽

C Bayer

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Greenhouse Gases ◽

Soil Carbon ◽

Carbon Stocks ◽

Soil Tillage ◽

Nitrous Oxide Emissions ◽

Greenhouse Gases Emissions ◽

Soil Carbon Stocks ◽

Grassland Biome

The southern Brazilian grassland biome contains highly diverse natural ecosystems that have been used for centuries for grazing livestock and that also provide other important environmental services. Here we outline the main factors controlling ecosystem processes, review and discuss the available data on soil carbon stocks and greenhouse gases emissions from soils, and suggest opportunities for mitigation of climatic change. The research on carbon and greenhouse gases emissions in these ecosystems is recent and the results are still fragmented. The available data indicate that the southern Brazilian natural grassland ecosystems under adequate management contain important stocks of organic carbon in the soil, and therefore their conservation is relevant for the mitigation of climate change. Furthermore, these ecosystems show a great and rapid loss of soil organic carbon when converted to crops based on conventional tillage practices. However, in the already converted areas there is potential to mitigate greenhouse gas emissions by using cropping systems based on no soil tillage and cover-crops, and the effect is mainly related to the potential of these crop systems to accumulate soil organic carbon in the soil at rates that surpass the increased soil nitrous oxide emissions. Further modelling with these results associated with geographic information systems could generate regional estimates of carbon balance.

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Soil Carbon Transitions Supporting Climate Change Mitigation

Sains Tanah - Journal of Soil Science and Agroclimatology ◽

10.20961/stjssa.v15i2.24972 ◽

2018 ◽

Vol 15 (2) ◽

pp. 134

Author(s):

Kurniatun Hairiah

Keyword(s):

Soil Carbon ◽

Agricultural Intensification ◽

Climate Change Mitigation ◽

Agricultural Land ◽

Soil Management ◽

Carbon Stocks ◽

Soil Carbon Storage ◽

Soil Carbon Stocks ◽

Supporting Soil ◽

Change Mitigation

Maintaining and where feasible restoring soil carbon stocks is part of all sustainable development strategies that have a chance of meeting the global commitment of the Paris Agreement to contain global warming within a 1.5oC limit. Active policies to incentivize increased soil carbon storage require understanding of the drivers of soil carbon decline, as well as the conditions under which soil management leads to an increase. Soil carbon transitions -- shifts from decline to increase of soil carbon stocks -- have been recorded as part of agricultural intensification. Organic inputs supporting soil carbon may primarily depend on roots, rather than aboveground inputs, and thus on the choice of crops, trees, and grasses that make up an agricultural land use system.

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