Water Level Has Higher Influence on Soil Organic Carbon and Microbial Community in Poyang Lake Wetland Than Vegetation Type

Although microorganisms play a key role in the carbon cycle of the Poyang Lake wetland, the relationship between soil microbial community structure and organic carbon characteristics is unknown. Herein, high-throughput sequencing technology was used to explore the effects of water level (low and high levels above the water table) and vegetation types (Persicaria hydropiper and Triarrhena lutarioriparia) on microbial community characteristics in the Poyang Lake wetland, and the relationships between soil microbial and organic carbon characteristics were revealed. The results showed that water level had a significant effect on organic carbon characteristics, and that soil total nitrogen, organic carbon, recombinant organic carbon, particle organic carbon, and microbial biomass carbon were higher at low levels above the water table. A positive correlation was noted between soil water content and organic carbon characteristics. Water level and vegetation type significantly affected soil bacterial and fungal diversity, with water level exerting a higher effect than vegetation type. The impacts of water level and vegetation type were higher on fungi than on bacteria. The bacterial diversity and evenness were significantly higher at high levels above the water table, whereas an opposite trend was noted among fungi. The bacterial and fungal richness in T. lutarioriparia community soil was higher than that in P. hydropiper community soil. Although both water level and vegetation type had significant effects on bacterial and fungal community structures, the water level had a higher impact than vegetation type. The bacterial and fungal community changes were the opposite at different water levels but remained the same in different vegetation soils. The organic carbon characteristics of wetland soil were negatively correlated with bacterial diversity but positively correlated with fungal diversity. Soil water content, soluble organic carbon, C/N, and microbial biomass carbon were the key soil factors affecting the wetland microbial community. Acidobacteria, Alphaproteobacteria, Verrucomicrobia, Gammaproteobacteria, and Eurotiomycetes were the key microbiota affecting the soil carbon cycle in the Poyang Lake wetland. Thus, water and carbon sources were the limiting factors for bacteria and fungi in wetlands with low soil water content (30%). Hence, the results provided a theoretical basis for understanding the microbial-driven mechanism of the wetland carbon cycle.

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Soil Water Content and Organic Carbon Availability Are Major Determinants of Soil Microbial Community Composition

Microbial Ecology ◽

10.1007/s00248-003-1063-2 ◽

2004 ◽

Vol 48 (3) ◽

pp. 424-430 ◽

Cited By ~ 311

Author(s):

R.E. Drenovsky ◽

D. Vo ◽

K.J. Graham ◽

K.M. Scow

Keyword(s):

Microbial Community ◽

Organic Carbon ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Soil Microbial Community ◽

Microbial Community Composition ◽

Carbon Availability ◽

Soil Microbial ◽

Soil Microbial Community Composition

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Can a single dose of biochar affect selected soil physical and chemical characteristics?

Journal of Hydrology and Hydromechanics ◽

10.2478/johh-2018-0034 ◽

2018 ◽

Vol 66 (4) ◽

pp. 421-428 ◽

Cited By ~ 8

Author(s):

Dušan Igaz ◽

Vladimír Šimanský ◽

Ján Horák ◽

Elena Kondrlová ◽

Jana Domanová ◽

...

Keyword(s):

Organic Carbon ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Base Cations ◽

N Fertilization ◽

Exchange Capacity ◽

Organic Carbon Content ◽

Soil Sorption ◽

Linear Relationships

Abstract During the last decade, biochar has captured the attention of agriculturalists worldwide due to its positive effect on the environment. To verify the biochar effects on organic carbon content, soil sorption, and soil physical properties under the mild climate of Central Europe, we established a field experiment. This was carried out on a silty loam Haplic Luvisol at the Malanta experimental site of the Slovak Agricultural University in Nitra with five treatments: Control (biochar 0 t ha−1, nitrogen 0 kg ha−1); B10 (biochar 10 t ha−1, nitrogen 0 kg ha−1); B20 (biochar 20 t ha−1, nitrogen 0 kg ha−1); B10+N (biochar 10 t ha−1, nitrogen 160 kg ha−1) and B20+N (biochar 20 t ha−1, nitrogen 160 kg ha−1). Applied biochar increased total and available soil water content in all fertilized treatments. Based on the results from the spring soil sampling (porosity and water retention curves), we found a statistically significant increase in the soil water content for all fertilized treatments. Furthermore, biochar (with or without N fertilization) significantly decreased hydrolytic acidity and increased total organic carbon. After biochar amendment, the soil sorption complex became fully saturated mainly by the basic cations. Statistically significant linear relationships were observed between the porosity and (A) sum of base cations, (B) cation exchange capacity, (C) base saturation.

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Effects of biotic and abiotic indices on soil water content in a decade-long grassland biodiversity experiment

10.5194/egusphere-egu2020-10981 ◽

2020 ◽

Author(s):

Christine Fischer ◽

Sophia Leimer ◽

Christiane Roscher ◽

Janneke Ravenek ◽

Hans de Kroon ◽

...

Keyword(s):

Species Richness ◽

Soil Moisture ◽

Organic Carbon ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Functional Groups ◽

Plant Species ◽

Plant Species Richness

Soil moisture is the dynamic link between climate, soil and vegetation and the dynamics and variation are affected by several often interrelated factors such as soil texture, soil structural parameters (soil organic carbon) and vegetation parameters (e.g. belowground- and aboveground biomass). For the characterization of soil moisture, including its variability and the resulting water and matter fluxes, the knowledge of the relative importance of these factors is of major challenge. Because of the spatial heterogeneity of its drivers soil moisture varies strongly over time and space. Our objective was to assess the spatio-temporal variability of soil moisture and factors which could explain that variability, like soil properties and vegetation cover, in in a long term biodiversity experiment (Jena Experiment).The Jena Experiment consist 86 plots on which plant species richness (0, 1, 2, 4, 8, 16, and 60) and functional groups (legumes, grasses, tall herbs, and small herbs) were manipulated in a factorial design Soil moisture measurements were performed weekly April to September 2003-2005 and 2008-2013 in 0.1, 0.2, 0.3, 0.4, and 0.6 m soil depth using Delta T theta probe.The analysis showed that both plant species richness and the presence of particular functional groups affected soil water content, while functional group richness per se played no role. Plots containing grasses was consistently drier than average at the soil surface in all observed years while plots containing legumes comparatively moister, but only up to the year 2008.Interestingly, plant species richness led to moister than average subsoil at the beginning of the experiment (2003 and 2004), which changed to lower than average up to the year 2010 in all depths.Shortly after establishment, increased topsoil water content was related to higher leaf area index in species&#8208;rich plots, which enhanced shading. In later years, higher species richness increased topsoil organic carbon, likely improving soil aggregation. Improved aggregation, in turn, dried topsoils in species&#8208;rich plots due to faster drainage of rainwater.Our decade&#8208;long experiment shows that besides abiotic factors like texture, soil water patterns are consistently affected by biotic factors such as species diversity and plant functional types, but also properties that originate from biotic-abiotic interactions such as soil structure. Especially the effect of plant species richness propagated to deeper soil layers 8 years after the establishment of the experiment, and while originally caused by shading it was later related to altered soil physical characteristics in addition to modification of water uptake depth. Functional groups affected soil water distribution, likely due to plant traits affecting root water uptake depths, shading, or water&#8208;use efficiency. Our results highlight the role of vegetation composition for soil processes and emphasize the need for long-term experiments to discover diversity effects in slow reacting systems like soil.

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Peanut mechanized digging regarding to plant population and soil water level

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/s1415-43662014000400015 ◽

2014 ◽

Vol 18 (4) ◽

pp. 459-465 ◽

Cited By ~ 4

Author(s):

Cristiano Zerbato ◽

Vicente F. A. Silva ◽

Luma S. Torres ◽

Rouverson P. da Silva ◽

Carlos E. A. Furlani

Keyword(s):

Water Content ◽

Water Level ◽

Soil Water ◽

Soil Water Content ◽

Material Flow ◽

Block Design ◽

Plant Population ◽

Plant Populations ◽

Randomized Block Design

The largest losses in mechanical harvesting of peanuts occur during the stage of digging, and its assessment is still incipient in Brazil. Therefore, the aim of this study was to evaluate the quantitative losses and the performance of the tractor-digger-inverter, according to soil water content and plant populations. The experiment was conducted in a completely randomized block design with a factorial scheme 2 x 3, in which the treatments consisted of two soil, water content (19.3 and 24.8%) and three populations of plants (86,111, 127,603 and 141,144 plants ha-1), with four replications. The quantitative digging losses and the set mechanized performance were evaluated. The largest amount of visible and total losses was found in the population of 141.144 plants ha-1 for the 19.3% soil water content. The harvested material flow and the tractor-digger-inverter performance were not influenced by soil water content and plant population. The water content in the pods was higher in 24.8% soil water content only for the population of 86,111 plants ha-1; the yield was higher in the populations of 141.144 and 127.603 plants ha-1, in the 19.3 e 24.8% soil water content, respectively.

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Importance of soil organic carbon on surface soil water content variability among agricultural fields

Journal of Hydrology ◽

10.1016/j.jhydrol.2013.11.018 ◽

2014 ◽

Vol 516 ◽

pp. 297-303 ◽

Cited By ~ 27

Author(s):

Hida R. Manns ◽

Aaron A. Berg

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Surface Soil ◽

Agricultural Fields

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Projected soil organic carbon loss in response to climate warming and soil water content in a loess watershed

Carbon Balance and Management ◽

10.1186/s13021-021-00187-2 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Fubo Zhao ◽

Yiping Wu ◽

Jinyu Hui ◽

Bellie Sivakumar ◽

Xianyong Meng ◽

...

Keyword(s):

Climate Change ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Climate Warming ◽

Root Zone ◽

Warming Climate ◽

The Future

Abstract Background Soil organic carbon (SOC) plays a crucial role in the global carbon cycle and terrestrial ecosystem functions. It is widely known that climate change and soil water content (SWC) could influence the SOC dynamics; however, there are still debates about how climate change, especially climate warming, and SWC impact SOC. We investigated the spatiotemporal changes in SOC and its responses to climate warming and root-zone SWC change using the coupled hydro-biogeochemical model (SWAT-DayCent) and climate scenarios data derived under the three Representative Concentration Pathways (RCPs2.6, 4.5, and 8.5) from five downscaled Global Climate Models (GCMs) in a typical loess watershed––the Jinghe River Basin (JRB) on the Chinese Loess Plateau. Results The air temperature would increase significantly during the future period (2017–2099), while the annual precipitation would increase by 2.0–13.1% relative to the baseline period (1976–2016), indicating a warmer and wetter future in the JRB. Driven by the precipitation variation, the root-zone SWC would also increase (by up to 27.9% relative to the baseline under RCP4.5); however, the SOC was projected to decrease significantly under the future warming climate. The combined effects of climate warming and SWC change could more reasonably explain the SOC loss, and this formed hump-shaped response surfaces between SOC loss and warming-SWC interactions under both RCP2.6 and 8.5, which can help explain diverse warming effects on SOC with changing SWC. Conclusions The study showed a significant potential carbon source under the future warmer and wetter climate in the JRB, and the SOC loss was largely controlled by future climate warming and the root-zone SWC as well. The hump-shaped responses of the SOC loss to climate warming and SWC change demonstrated that the SWC could mediate the warming effects on SOC loss, but this mediation largely depended on the SWC changing magnitude (drier or wetter soil conditions). This mediation mechanism about the effect of SWC on SOC would be valuable for enhancing soil carbon sequestration in a warming climate on the Loess Plateau.

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Numerical Study of Unsaturated Expansive Soil Canal Slope Covered by Geo-Membrane

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.744-746.551 ◽

2015 ◽

Vol 744-746 ◽

pp. 551-554

Author(s):

Wen Qing Wu ◽

Jiang Hu Chen ◽

Hong Yu Zhang ◽

Jun Hua Wu

Keyword(s):

Water Content ◽

Water Level ◽

Soil Water ◽

Soil Water Content ◽

Pore Water Pressure ◽

Numerical Study ◽

Water Pressure ◽

Expansive Soil ◽

Seepage Field ◽

Unsaturated Expansive Soil

In view of the holes appearing in different areas of geo-membrane when the geo-membrane technology is applied to the unsaturated expansive soil canal slope, the VADOSE/W is used to analyze the pore-water pressure of the internal canal slope by changing the falling water level. The results show that the hole is nearer to the toe of slope, its effect on the whole seepage field is greater. The greater the rate is, the soil water content is greater.

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A near infrared index to assess effects of soil texture and organic carbon content on soil water content

European Journal of Soil Science ◽

10.1111/ejss.12725 ◽

2018 ◽

Vol 70 (1) ◽

pp. 151-161 ◽

Cited By ~ 3

Author(s):

I. Soltani ◽

Y. Fouad ◽

D. Michot ◽

P. Bréger ◽

R. Dubois ◽

...

Keyword(s):

Organic Carbon ◽

Carbon Content ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Soil Texture ◽

Near Infrared ◽

Organic Carbon Content

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Soil contribution to CO2 fluxes in Chinampa ecosystems, Mexico

Spanish Journal of Soil Science ◽

10.3232/sjss.2020.v10.n2.04 ◽

2020 ◽

Vol 10 ◽

Author(s):

Elena Nikolaevna Ikkonen ◽

Norma Eugenia García-Calderón ◽

Ervin Stephan-Otto ◽

Elizabeth Fuentes-Romero ◽

Abel Ibáñez-Huerta ◽

...

Keyword(s):

Seasonal Variation ◽

Plant Growth ◽

Water Content ◽

Soil Water ◽

Soil Water Content ◽

Seasonal Dynamics ◽

Plant Biomass ◽

Vegetation Type ◽

Ecosystem Carbon ◽

Dominant Plant Species

Since soil CO2 flux is a key component of ecosystem carbon balance, quantifying its contribution to the ecosystem carbon flux and understanding the factors that underlie its temporal variation is crucial for a better comprehension of ecosystem carbon dynamics under climate change and for optimal ecosystem use and management. Our objectives were to quantify the contributions of total soil CO2 efflux (FS) to ecosystem respiration (RE) and heterotrophic soil CO2 efflux (FH) to FS in two chinampa ecosystems with different natural grass covers. We also aimed to identify the main environmental drivers of seasonal variability of these contributions. The CO2 fluxes were measured on each site about every 14 days from September 2008 to August 2009 in the Xochimilco Ecological Park in Mexico City using dark chamber techniques. For two studied sites, RE, FS and FH were estimated on average as 94.1 ± 8.5, 34.7 ± 3.5 and 16.5 ± 1.7 (± S.E.) mg C-CO2 m-2 h-1, respectively.  On average over the study period and sites, the annual cumulative RE, FS and FH fluxes were 824 ± 74, 304 ± 31 and 145 ± 15 g C m-2 year, respectively. The RE, FS and FH varied between the winter and summer seasons; this variation was explained mostly by seasonal variations of soil temperature, soil water content and shoot plant biomass. Temperature sensitivity of CO2 fluxes depended on vegetation type and plant growth differences among the sites and decreased in the following order: RE > Rs > RH. The contribution of FS to RE and FH to FS for the two studied sites and period averaged about 38% and 50%, respectively regardless of the site vegetation type, but the degree of FS/RE and FH/FS variability depended on the differences in seasonal dynamics of plant cover. The contribution of FH to FS varied from 37% in summer to 73% in winter at the site without a seasonal shift in dominant plant species, but FH/FS was close to constant during the year at the site with a seasonal change in dominant plant species. During the cold period, the contribution of FH to FS increased following plant growth decrease. The linear regression analysis showed that plant biomass was the dominant factor controlling the seasonal variation of FH/FS ratios, whereas the plant biomass dynamic followed the dynamics of soil water content, water table depth, and soil temperature. Our results suggest that seasonal variation of soil contribution to total fluxes from the chinampa ecosystem is locally differentiated. These differences were related to differences in seasonal dynamics of cover productivity which has been associated with localization of soil water content. This finding has important implications for assessing the contribution of the chinampa ecosystem to the global carbon budget.

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