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[Objective] Soil organic carbon (SOC) is not only an indicator of soil health but also plays a crucial role in feedback interaction between global warming and carbon stock in terrestrial ecosystems. Its dynamics is modulated by a multitude of interactive abiotic and biotic factors. In this paper, we analyze the spatial distribution of SOC in the plough layer and its correlation with soil texture and other geochemical properties in the region of Zhengzhou in Henan province. [Method] Soil samples were taken from a grid network in the region. SOC, bulk density, soil texture and other geochemical properties in each soil sample were measured. The correlation between SOC and soil nutrients, including nitrogen, phosphorus, potassium and micronutrients in the soil, was analyzed using the GeoChemStudio software. [Result] The calcareous skeletol soil in the region has the highest SOC, reaching 2.307%. The SOC content varied from 0.1%-11.6% across the region, and was normally distributed with a mean of 1.134%. The SOC was positively correlated with N, P2O5, Fe, Mn, Zn, Cu, Mo and B, and their associated correlation coefficients were 0.804 5, 0.223 0, 0.156 3, 0.119 1, 0.223 8, 0.263 4, 0.162 8 and 0.191 1, respectively. Negative correlations were found between SOC and K2O and pH, and their associated correlation coefficients were -0.088 8 and -0.195 7, respectively. The average SOC content in the plough layer in the region was 1.09%. Spatially, SOC was rich in Xinmi, Dengfeng and Gongyi in the southwest of the region. In terms of soil texture, SOC is higher in skeletol soil and calcareous cinnamon soil than in other soils. SOC stored in the topsoil in the whole region was 1 012.87x104 t, with 523.13x104 t stored in the cinnamon soils and calcareous cinnamon soils, accounting for 51.64% of the total topsoil SOC in the region. [ABSTRACT FROM AUTHOR]

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the scarcity of biological resources, desert areas are unable to achieve long-term carbon sequestration. Biological crust is a pioneer organism in desert areas and plays an important role in long-term carbon sequestration. However, the development of natural biological crust is slow. Clay plays an important role in the formation and development of biological crusts, and has a strong protective effect on soil organic carbon. Therefore, this paper explores the impact and mechanism of adding kaolin on the organic carbon of soil biological crust system, aiming to provide new solutions for the long-term carbon sink in desert areas. Through testing particle size, specific surface area and pore volume, chlorophyll a, chlorophyll fluorescence, microbial community, and soil organic carbon (SOC), it has been found that the addition of kaolin changed the physicochemical properties and microbial community structure of the system, promoted the growth of biochar, and strengthened the protective effect of the system on SOC. After 112 days of cultivation, the results show that the accumulation of SOC in the kaolin-based biological crust system increases to 145% of the algae inoculation group. [ABSTRACT FROM AUTHOR]

Copyright of Forest Engineering is the property of Forest Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to study the effects of exogenous straw carbon addition on the organic carbon composition and rice growth characteristics of calcareous paddy soil in karst area, providing reference basis for exploring the changes in carbon composition of alcareous paddy soil in karst areas. 【Method】The rice pot experiment was carried out in the greenhouse of Yanshan Campus of Guilin University of Technology in March 2023, and the experiment period was 120 d. A total of 19 treatments were set up in the pot experiment. In the treatment that only added straw carbon, 0.5%, 1.0% and 3.0% （dry soil mass ratio） crushed straw, straw compost and straw biochar were added, respectively. In the treatment of adding straw carbon and calcium carbonate, the carbon content of the three kinds of straw was 1.0%, and on this basis, 0, 10.0% and 20.0% （dry soil mass ratio） calcium carbonate were added, respectively. At the same time, the control （CK） treatment without adding any substances was set up. The growth characteristics of rice and the changes of soil organic carbon components microbial biomass carbon （MBC), dissolved organic carbon （DOC), granular organic carbon （POC） and their influencing factors were analyzed.【Result】The type and amount of straw carbon had an impact on the content of organic carbon components in the soil. Adding 0.5% straw compost resulted in the highest MBC content in soil （235.73 mg/kg), while adding 1.0% straw compost resulted in the highest DOC content in soil （221.50 mg/kg). The soil treated with 3.0% straw biochar had the highest POC content （36.20 mg/kg). The content of calcium carbonate in soil also affected the composition of soil organic carbon. When the content of calcium carbonate was 20.0%, the soil MBC contents in the treatments adding three straw carbons were the highest. The soil with 10.0% calcium carbonate+1.0% straw compost had the highest DOC content （195.60 mg/kg). The effects of adding three kinds of straw carbon on the growth of rice were as follows: straw biochar ＞ straw compost ＞ broken straw. Among them, the rice with 0.5% straw biochar added had the best growth, with an average plant height of 102 cm and root length of 50 cm. Addition 3.0% crushed straw had the strongest inhibitory effect on rice growth. With the increase of calcium carbonate addition, the rice plant height treated by straw compost increased first and then decreased, and the addition of 10.0% calcium carbonate had a stronger effect on plant height. The correlation analysis results showed that the amount of straw biochar was significantly negatively correlated with soil DOC content （P ＜ 0.05, the same below), and extremely significantly positively correlated with soil POC content （P ＜ 0.01). There was a significant positive correlation between calcium carbonate addition and soil DOC content.【Conclusion】Exogenous straw carbon has a positive excitation effect on the active organic carbon components in calcareous paddy soil, which can greatly increase the contents of MBC, DOC and POC in soil, and the addition of straw carbon and calcium carbonate has a synergistic effect on the increase of soil active carbon components. Adding low amount of straw carbon can promote rice growth, and straw biochar has the most obvious promoting effect. Adding straw compost and straw biochar to soils with 10.0% and 20.0% calcium carbonate concentrations can promote rice growth [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

(Objective) Aggregation is an important soil health indicator modulating many soil functions including nutrient bioavailability and carbon sequestration. It is affected by a multitude of factors. The purpose of this paper is to study the effect of irrigation and nitrogen fertilization on soil aggregation and soil organic carbon. (Method) The experiment was conducted in a winter wheat field. It consisted of two nitrogen applications: 0 (N0) and 180 kg/hm2 (N180), two irrigation treatments: sufficient irrigation (F) and deficit irrigation using 65% of the water in F. In each treatments, we measured water-stable aggregates and soil organic carbon.(Result) 1 Deficit irrigation coupled with nitrogen fertilization increased water-stable macroaggregates with diameter ≥0.25 mm. Nitrogen fertilization increased organic carbon in the top 0~30 cm soil layer by more than 3.59% when irrigation was the same, while deficit irrigation increased organic carbon in the same soil layer by more than 2.86% when nitrogen fertilization was the same. 2 Soil moisture directly affected soil carbon, explaining 83.9% of the change in total organic carbon, while nitrogen indirectly affected soil carbon, explaining 46.89% of change in the total organic carbon. 3 The direct impact of water-stable aggregates on soil carbon was negative, while its direct influence was positive.(Conclusion) The effect of nitrogen fertilization on soil aggregation was modulated by irrigation. Nitrogen fertilization combined with deficient irrigation boosted carbon accumulation in the topsoil. [ABSTRACT FROM AUTHOR]

Copyright of Forest Engineering is the property of Forest Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The soil-air exchange behavior of persistent organic pollutants (POPs) plays a significant role in the distribution and fate in the two phases. This paper summarizes the selective behaviors of typical POPs contaminants and their homologues and isomers in soil-air exchange from the four aspects: sampling techniques, fugacity models, exchange directions and fluxes, as well as influencing factors. Dichlorodiphenyltrichloroethane (DDTs) and their metabolites o, p'-DDT ... p,p.-DDD show the trend of net deposition from various studies. α-, β- hexachlorocyclohexane (HCHs) prefers to migrate from soil to atmosphere than γ-, δ- HCH. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) with lower molecular weight compounds are generally volatilized to the atmosphere. Polybrominated diphenyl ethers (PBDEs) with low bromination degree have higher liquidity. Compared with other organophosphorus flame retardants, tributyl phosphate has a higher volatilization trend. For the novel pollutants, the exchange fluxes of perfluorooctanesulfonate (PFOS) and short-/medium-chain chlorinated paraffins (CPs) have been reported. The direction of soil-air exchange is also affected by temperature and soil organic carbon content. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The present paper aimed to study the impact of organic and inorganic combined application on the organic carbon composition, carbon bank management index and organic carbon functional group of tobacco planting soil in Wuxi county, so as to provide reference for improving the quality of tobacco planting soil and reasonable fertilization. [Method] Four treatments were set up under the condition of constant nitrogen input in field experiment: chemical fertilizer（CF）, chemical fertilizer with mushroom slag organic fertilizer（CMO）, chemical fertilizer with high carbon-based fertilizer（CHB）, and chemical fertilizer with biological organic fertilizer（CBO）. The effect of organic and inorganic application on soil carbon reservoir was studied by measuring total organic carbon and active carbon functional group structure using Fourier infrared spectrometry（FTIR）. [Result] （i） Compared with single organic fertilizer, the soil supplemented with organic fertilizer was slightly increased, and there was no significant difference between the treatments, significantly increased the output value on flue-cured tobacco leaf;（ii） The DOC, MBC content of the soil active carbon bank treated with organic fertilizer was significantly higher than that of single chemical fertilizer treatment. Among them, CMO treatment showed the largest increase in soil DOC content, thus being 67. 13%, 12. 84%, and 28. 54% higher than CF, CHB, CBO, respectively. CBO treatment showed the most increase in soil MBC content, with soil MBC content increasing 42. 32% compared to CF and CHB treatment showing 11. 43% higher soil EOC compared to CF;（iii）Among the three organic fertilizers, the DOC distribution of DOC, CMO, CBO, EOC, and the carbon bank management index of CHB treatment was significantly greater than CF and CMO;（iv） The structure difference of each treated organic carbon functional group was small, which mainly included phenols, aromatic hydrocarbons, olefins and mesamides. The relative peak area at 1634 cm-1 was associated significantly positively with soil MBC content, and that at 468 cm-1 was associated significantly negatively with soil TOC content. [Conclusion] Compared with single organic fertilizer, soil organic residue organic fertilizer significantly improved soil DOC and MBC content and high carbon-based fertilizer significantly improved soil EOC content and carbon bank management index. Short-term organic and inorganic distribution had little impact on organic carbon functional groups. However, the peaks at 1634 and 468 cm-1 were significantly associated with the soil TOC and MBC content. At the same time, organic-inorganic fertilizer significantly increased the yield and output value of flue-cured tobacco. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central China Normal University is the property of Huazhong Normal University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Alpine wetland ecological environment is fragile and sensitive to global change. The present paper aimed to explore the response mechanism of soil physical and chemical properties to nitrogen deposition in alpine wetland. [Method] Four levels of CK（0 g/m2）,N2（2 g/m2）,N5（5 g/m2） and N10（10 g/m2） nitrogen addition tests were set in Xiaopo Lake Wetland in Qinghai Lake basin as the research object. Simulated nitrogen deposition test was conducted from June to October 2019.Samples were taken in October 2019 to determine soil water content, pH, organic carbon, total carbon, total nitrogen and inorganic nitrogen, and analyze the influence of nitrogen deposition test on soil physical and chemical properties.[Result]（i）Nitrogen deposition reduced soil moisture content and increased soil pH, and the influence reached extremely significant level（P<0.01）.(ii)Nitrogen deposition made soil carbon nitrogen content change. Total carbon organic nitrogen and ammonia nitrogen decreased with the increase of nitrogen concentration, and the influence on total carbon content was significant(P<0.05).The effect of nitrate nitrogen in the two soil layers was different. In the 0-15 cm soil layer, it increased with the increase of nitrogen concentration, and reached a significant level under the treatment of N10（P<0.05）,decreased with the increase of nitrogen concentration in the 15-30 cm soil layer.(iii) Soil moisture content was the main factor affecting soil organic carbon and total nitrogen.Soil inorganic nitrogen was not closely related to other factors, but there was a very significant correlation between soil organic carbon and total nitrogen(P<0.01).[Conclusion]The present study provides reference for the change of soil environment and the protection and utilization of wetland under the global change. [ABSTRACT FROM AUTHOR]