Solid-solution partitioning of arsenic (As) in the paddy soil profiles in Chengdu Plain, Southwest China

Soil carbon and nitrogen storage and stabilization are the key to solving the problems of mitigation of global warming and maintaining of crop productivity. In this study, the contents of soil organic carbon (SOC) and soil organic nitrogen (SON) and their stable isotope compositions (δ13CSOC and δ15NSON) in soil profiles were determined in two agricultural lands (including a farmland and an abandoned farmland) and four non-agricultural lands (including two shrub-grass lands and two shrub lands) in the karst critical zone observatory (CZO), Southwest China. The contents of SOC and SON were used for research on the effects of land use on SOC and SON storage, and the change of δ13CSOC and δ15NSON values in soil profiles were used to indicate SOC and SON stabilization. The results showed that agricultural activities reduced SOC and SON storage in the whole soil layers of farmland compared to non-agricultural lands, and farmland abandonment slightly increased SOC and SON storage. Crop rotation between peanut (C3) and corn (C4) affected the δ13CSOC in surface soils of agricultural lands (−21.6‰), which were intermediate between shrub lands (−22.7‰) and shrub-grass lands (−19.6‰). 15N-depleted SON in surface soils in farmland compared to those soil in other lands possibly associated with synthetic N fertilizer application. In soil layers below 30 cm depth the δ13CSOC deceased with depth, while the δ15NSON displayed irregular fluctuation. The change in δ13CSOC and δ15NSON through soil profiles in karst soils were more intensive than those in semiarid grassland soils indicating the less stabilization of SOC and SON in karst soils.

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Characteristics and distributions of humic acids in two soil profiles of the southwest China Karst area

Acta Geochimica ◽

10.1007/s11631-015-0086-y ◽

2015 ◽

Vol 35 (1) ◽

pp. 85-94 ◽

Cited By ~ 2

Author(s):

Liangang Ma ◽

Baohua Xiao ◽

Xinyue Di ◽

Weilin Huang ◽

Shijie Wang

Keyword(s):

Humic Acids ◽

Southwest China ◽

Karst Area ◽

Soil Profiles

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Assessment of Arsenic Distribution in Paddy Soil and Rice Plants of a Typical Karst Basin Affected by Acid Mine Drainage in Southwest China

Environment and Pollution ◽

10.5539/ep.v2n2p27 ◽

2013 ◽

Vol 2 (2) ◽

Cited By ~ 5

Author(s):

Chipeng Zhang ◽

Pan Wu ◽

Changyuan Tang ◽

Zhiwei Han ◽

Jing Sun

Keyword(s):

Acid Mine Drainage ◽

Paddy Soil ◽

Southwest China ◽

Mine Drainage ◽

Rice Plants ◽

Acid Mine ◽

Arsenic Distribution

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Distribution characteristics and diversities of cbb and coxL genes in paddy soil profiles from southern China

Pedosphere ◽

10.1016/s1002-0160(21)60027-9 ◽

2021 ◽

Vol 31 (6) ◽

pp. 954-963

Author(s):

Wentao PENG ◽

Yan WANG ◽

Xiuxiu ZHU ◽

Liufeng XU ◽

Juan ZHAO ◽

...

Keyword(s):

Paddy Soil ◽

Southern China ◽

Soil Profiles ◽

Distribution Characteristics

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Multiple role of diazotrophs in coupling nitrogen and iron biogeochemical processes through vertical soil profiles of different paddy soil types

10.21203/rs.3.rs-97358/v1 ◽

2020 ◽

Author(s):

Xiaomi Wang ◽

Ying Teng ◽

Wenjie Ren ◽

Yuntao Li ◽

Teng Yang ◽

...

Keyword(s):

Paddy Soil ◽

Soil Types ◽

Soil Profiles ◽

Biogeochemical Processes ◽

Multiple Role ◽

Iron Cycling ◽

Element Cycling ◽

Edaphic Properties ◽

Developmental Features ◽

Cycling Index

Abstract Background: Soil microbiota exert fundamental functions in maintaining ecosystem functioning and services, including pedogenesis, biogeochemical processes and plant productivity, especially for agriculture system. Despite their ubiquitousness from the epipedon to deep soil, the vertical characteristics of microbiomes (especially for functional microorganisms) and their contribution to soil element cycling when considering soil developmental features are poorly understood. Here, nine profiles (0~135 cm) of two canonical paddy soil types (Fe-accumuli- and Hapli-stagnic anthrosols; 111 samples in total) at a local scale were collected, which represented relative long- and short-term water flooding history, respectively. The vertical variations in edaphic characteristics and assemblies of soil bacterial and diazotrophic communities, and microbial contribution to element cycling were explored. Results: Across soil profiles, Hapli-stagnic anthrosol was characteristic of higher concentrations in free iron oxides and total iron in the epipedon, and contained higher amounts of ammonia along the subsurface layers, as compared with acidic Fe-accumuli-anthrosol. Community assemblies of bacteria and diazotrophs, as well as edaphic properties, were mainly shaped by soil depths, followed by soil types. Furthermore, random forest analysis revealed that, for Fe-accumuli-anthrosol, available Fe could best predict nitrogen cycling index and nitrogen status was significantly related to iron cycling index; while in Hapli-stagnic anthrosol, available sulfur was the most important variable in predicting nitrogen and iron cycling indices. Among the dominant genera, some distinctive biomarkers that varied remarkably between the two soil types were noticeable for their contributions to both nitrogen and iron transformation, including iron-reducing diazotroph Geobacter and iron-oxidizing bacterium Rhodanobacter that characterized Fe-accumuli type, and sulfur reducing diazotroph Desulfobacca as main discriminant clades for Hapli-stagnic type.Conclusions: A novel perspective was proposed on the vertical characteristics of edaphic properties and bacterial and diazotrophic communities in the two paddy soil types. The findings indicated the nitrogen-iron cycling processes for Fe-accumuli-anthrosol and nitrogen-iron-sulfur coupling interaction for Hapli-stagnic anthrosol, advancing our understanding of the significant multiple role played by soil microorganisms, especially for diazotrophs, in element biogeochemical cycles.

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Farmers’ Strategies to Climate Change and Urbanization: Potential of Ecosystem-Based Adaptation in Rural Chengdu, Southwest China

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph19020952 ◽

2022 ◽

Vol 19 (2) ◽

pp. 952

Author(s):

Bo Zhong ◽

Shuang Wu ◽

Geng Sun ◽

Ning Wu

Keyword(s):

Climate Change ◽

Rural Communities ◽

Southwest China ◽

Cost Effective ◽

Agricultural Systems ◽

Rural Landscapes ◽

Chengdu Plain ◽

New Perspective ◽

Study Sites ◽

Local Farmers

Ecosystem-based adaptation (EbA) is emerging as a cost-effective approach for helping people adapt to climate and non-climate changes. Nowadays, climate change and urbanization have affected agricultural systems, but it is not clear how rural communities have responded or adapted to those changes. Here, we chose two typical villages in the Chengdu Plain, southwest China, through sociological surveys on 90 local farmers with a semi-structured questionnaire, participatory observation, geospatial analysis of land use and land cover, and a literature review, to explore the local people’s perception of changes or disturbances and their adaptation strategies from the perspective of EbA. The results showed that climate change and urbanization had impacted agricultural systems dramatically in the last 40 years. In two case-study sites, climate change and urbanization were perceived by most local farmers as the main drivers impacting on agricultural production, but various resource-use models containing abundant traditional knowledge or practices as well as modern tools, such as information communication technology (ICT), were applied to adapt to these changes. Moreover, culture service through the adaptive decoration of rural landscapes is becoming a new perspective for implementing an EbA strategy. Finally, our findings highlighted the potential value of an EbA strategy for sustaining urban-rural integrated development and enhancing the resilience of agricultural systems.

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