Soil organic carbon and soil structure are driving microbial abundance and community composition across the arid and semi-arid grasslands in northern China

Edaphic arthropod communities provide valuable information about the prevailing status of soil quality to improve the functionality and long-term sustainability of soil management. The study aimed at evaluating the effect of plant and grass cover on the functional biodiversity and soil characteristics in a mature olive orchard (Olea europaea L.) managed for ten years by two conservation soil managements: natural grass cover (NC) and conservation tillage (CT). The trees under CT grew and yielded more than those under NC during the period of increasing yields (years 4–7) but not when they reached full production. Soil management did not affect the tree root density. Collecting samples underneath the canopy (UC) and in the inter-row space (IR), the edaphic environment was characterized by soil structure, hydrological properties, the concentration and storage of soil organic carbon pools and the distribution of microarthropod communities. The soil organic carbon pools (total and humified) were negatively affected by minimum tillage in IR, but not UC, without a loss in fruit and oil yield. The assemblages of microarthropods benefited, firstly, from the grass cover, secondly, from the canopy effect, and thirdly, from a soil structure ensuring a high air capacity and water storage. Feeding functional groups—hemiedaphic macrosaprophages, polyphages and predators—resulted in selecting the ecotonal microenvironment between the surface and edaphic habitat.

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Space-time monitoring of soil organic carbon content across a semi-arid region of Australia

Geoderma Regional ◽

10.1016/j.geodrs.2021.e00367 ◽

2021 ◽

Vol 24 ◽

pp. e00367

Author(s):

Patrick Filippi ◽

Stephen R. Cattle ◽

Matthew J. Pringle ◽

Thomas F.A. Bishop

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Carbon Content ◽

Arid Region ◽

Space Time ◽

Organic Carbon Content ◽

Soil Organic Carbon Content ◽

Semi Arid Region ◽

Semi Arid

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Responses of soil organic carbon mineralization and its temperature sensitivity to re-vegetation in the agro-pastoral ecotone of northern China

European Journal of Soil Biology ◽

10.1016/j.ejsobi.2021.103278 ◽

2021 ◽

Vol 103 ◽

pp. 103278

Author(s):

Yufei Yao ◽

Nannan Ge ◽

Xiaorong Wei ◽

Wei Fu ◽

Mingan Shao ◽

...

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Temperature Sensitivity ◽

Carbon Mineralization ◽

Northern China ◽

Soil Organic Carbon Mineralization ◽

Organic Carbon Mineralization

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Soil Organic Carbon Dynamics in Semi-Arid Irrigated Cropping Systems

Agronomy ◽

10.3390/agronomy11030484 ◽

2021 ◽

Vol 11 (3) ◽

pp. 484

Author(s):

Andrew M. Bierer ◽

April B. Leytem ◽

Robert S. Dungan ◽

Amber D. Moore ◽

David L. Bjorneberg

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Empirical Data ◽

Cropping Systems ◽

C Sequestration ◽

Conventional Tillage ◽

Dndc Model ◽

Application Timing ◽

Winter Triticale ◽

Semi Arid

Insufficient characterization of soil organic carbon (SOC) dynamics in semi-arid climates contributes uncertainty to SOC sequestration estimates. This study estimated changes in SOC (0–30 cm depth) due to variations in manure management, tillage regime, winter cover crop, and crop rotation in southern Idaho (USA). Empirical data were used to drive the Denitrification Decomposition (DNDC) model in a “default” and calibrated capacity and forecast SOC levels until 2050. Empirical data indicates: (i) no effect (p = 0.51) of winter triticale on SOC after 3 years; (ii) SOC accumulation (0.6 ± 0.5 Mg ha–1 year–1) under a rotation of corn-barley-alfalfax3 and no change (p = 0.905) in a rotation of wheat-potato-barley-sugarbeet; (iii) manure applied annually at rate 1X is not significantly different (p = 0.75) from biennial application at rate 2X; and (iv) no significant effect of manure application timing (p = 0.41, fall vs. spring). The DNDC model simulated empirical SOC and biomass C measurements adequately in a default capacity, yet specific issues were encountered. By 2050, model forecasting suggested: (i) triticale cover resulted in SOC accrual (0.05–0.27 Mg ha–1 year–1); (ii) when manure is applied, conventional tillage regimes are favored; and (iii) manure applied treatments accrue SOC suggesting a quadratic relationship (all R2 > 0.85 and all p < 0.0001), yet saturation behavior was not realized when extending the simulation to 2100. It is possible that under very large C inputs that C sequestration is favored by DNDC which may influence “NetZero” C initiatives.

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