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Copyright of China Mining Magazine is the property of China Mining Magazine Co., Ltd. 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.)

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui 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.)

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.)

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology 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.)

Methane, the second most prevalent greenhouse gas globally, is characterized by its high global warming potential and short atmospheric lifetime. It is primarily emitted from sectors such as coal mining, oil and gas production, agriculture, livestock rearing, and waste management. Active, prudent, and orderly control of methane emissions offers a multifaceted benefit: it mitigates global warming, enhances the economic value through the resource utilization of energy, provides environmental advantages by control of pollutants, and improves safety by reducing production accidents. Methane is also the principal greenhouse gas emitted in coal mine operations. Currently, monitoring and researching the distribution of methane emissions and their concentration within the three-dimensional space of coal mines have become a key focus in China’s methane emission control efforts, which is of significant importance for coal mining enterprises to align with national strategies. A study conducted on a high-gas mine in Shanxi and a low-gas mine in Shaanxi for methane emission monitoring and accounting utilized fixed monitoring, manual monitoring, drone monitoring, and post-mining activity monitoring to investigate the distribution of methane in high and low gas mines in China and to analyze their methane emissions. The results indicate that: ① The methane emission volumes for a certain high-gas mine in Shanxi and a low-gas mine in Shaanxi published by the U.S.-based Climate TRACE website for the year 2022 show a significant discrepancy from the results calculated using the ground measurement method, with the published annual methane emission volume for a certain low-gas mine being 10.92 times that of the ground measurement calculation. The top-down monitoring and accounting methods have been found to be insufficiently accurate and unable to provide reliable data support for carbon trading. ② In the monitoring and accounting of post-mining activities, the use of default values recommended by the IPCC results in methane emissions that are 3 to 5 times higher than those calculated using the ground measurement method, and there is a significant variation in the emissions calculated based on coal samples of different sizes and exposure durations. There is an urgent need for a unified and precise testing standard to ensure fair and accurate data for future carbon market transactions.

Copyright of Coal Science & Technology (0253-2336) is the property of Coal 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.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis 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.)

Essential oils are volatile aromatic substances extracted from flowers, leaves, stems, roots or fruits of plants. Plant essential oils come from a wide range of sources, whcih are green and safe, have strong antibacterial and antioxidant properties, and can participate in immune regulation, improve animal growth performance, improve meat quality, prevent and control diseases. The paper reviews the effect of plant essential oil on growth performance, rumen fermentation, methane emission and meat quality of beef cattle, providing some reference for the research and application of plant essential oil in beef cattle production. [ABSTRACT FROM AUTHOR]

Coalbed methane (CBM) development in coal mining area has good safety, economic and energy benefits, but methane emission is common in surface well sites. In view of this, taking the CBM wells in Qinshui County of Shanxi Province as an example, the methane emission location and emission volume of CBM wells are obtained, and the prediction model of methane emission volume is established through field investigation and multiple regression analysis. The results show that 81% of CBM wells have methane emission. Wellhead and drainage outlet are the two main positions of methane emission. The proportion of wells with emission volume between 0-10 m3/d is 59%. On the whole, the emission accounts for 1.53% of the gas well production. There is almost no methane emission in the single liquid phase flow stage. The methane emission in the gas-liquid two-phase flow stage is positively correlated with the bottom hole flow pressure, times of stroke and gas production, and negatively correlated with the pump embedment and water production. The bottom hole flow pressure and the pump embedment have the greatest impact on the methane emission. In the single-phase gas flow stage, methane emission is positively correlated with gas production and casing pressure, and negatively correlated with stroke frequency and water production.

The negative pressure of high level roadway extraction is one key factor which can influence coal spontaneous combustion and the gas extraction, to determine the reasonable negative pressure of extraction, combined with the actual situation of gas over-limit and spontaneous ignition in 401102 fully mechanized caving face of a mine, ANSYS numerical simulation and field measurement method were adopted to study the influence of negative pressure of extraction in high level roadway on gas extraction effect and “three zones” distribution of coal spontaneous combustion, and engineering practice was carried out. The results show that negative pressure can result in coal spontaneous combustion. When negative pressure increases from 0.5 kPa to 3.5 kPa, gas extraction scalar increase by 21.02 m3/min, compared with the “U” ventilation mode, when the negative pressure of the high roadway was 3 kPa, the width of the oxidation heating zone increased by 17 m on the inlet side, and decreased by 14 m in the middle and 11 m on the return side; the method of defining the range of reasonable negative pressure of extraction was proposed, and the fluctuation range of negative pressure was determined between 0.951 6 and 2.558, and the optimal point was 2.558 kPa. When high level roadway is adopted in coal seam, the reasonable setting of negative pressure can ensure the coupling prevention and control of gas and coal spontaneous combustion in goaf.

Tea saponin (TS) is extracted from the seeds, leaves or roots of tea plants. As a feed additive, tea saponin may be an effective way to inhibit methane emissions. The paper reviews the mitigation trend of methane emission and the effects of tea saponin on animal performance, in order to provide reference for the application of TS in ruminant production. [ABSTRACT FROM AUTHOR]

The appropriate amount of tannin in the diet can inhibit the excessive degradation of protein in the rumen, improve the absorption and utilization of protein in the intestinal tract, to improve the production performance of ruminants. Tannins can reduce the methane emissions by effecting the active of methanogens. The paper reviews the nutritional properties of tannins and the effect on ruminant production performance and methane emissions, to provide a reference for the application of tannins in ruminant diets. [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.)

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.)

Copyright of Acta Prataculturae Sinica is the property of Acta Prataculturae Sinica 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.)

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.)

Ant nests can affect the process and seasonal dynamics of forest soil methane emissions through mediating methane oxidation/reduction microorganisms and physicochemical environments. To explore the process and mechanism by which ant nests affect soil methane emissions from Hevea brasiliensis plantation in Xishuangbanna, we measured the seasonal dynamics of methane emissions from ant nest and non-nest soils by using static chamber-gas chromatography method, and analyzed the effect of ant nesting on the changes in functional microbial diversity, microhabitats, and soil nutrients in the plantations. The results showed that: 1) Ant nests significantly affected the mean annual soil methane emissions in tropical plantation. Methane emissions in ant nest were decreased by 59.9% than the non-nest soil. In the dry season, ant nest soil was a methane sink (-1.770 μg·m -2 ·h -1 ), which decreased by 87.2% compared with the non-nest soil, while it was a methane source (0.703 μg·m -2 ·h -1 ) that increased by 152.7% in the wet season. 2) Ant nesting affected methane emissions via changing soil temperature, humidity, carbon and nitrogen concentrations. In contrast to the control, the mean annual temperature, humidity, and carbon and nitrogen content increased by 4.9%-138.5% in ant nest soils, which explained 90.1%, 97.3%, 27.3%-90.0% of the variation in methane emissions, respectively. 3) Ant nesting affected the emission dynamics through changing the diversity and community structure of methane functional microbe. Compared with the control, the average annual methanogen diversity (Ace, Chao1, Shannon, and Simpson indices) in the ant nest ranged from -9.9% to 61.2%, which were higher than those (-8.7%-31.2%) of the methane-oxidising bacterial communities. The relative abundance fluctuations of methanogens and methanotrophic bacteria were 46.76% and -6.33%, respectively. The explaining rate of methanogen diversity to methane emissions (78.4%) was higher than that of oxidizing bacterial diversity (54.5%), the relative abundance explained by the dominant genus of methanogens was 68.9%. 4) The structural equation model showed that methanogen diversity, methanotroph diversity, and soil moisture were the main factors controlling methane emissions, contributing 95.6%, 95.0%, and 91.2% to the variations of emissions, respectively. The contribution (73.1%-87.7%) of soil temperature and carbon and nitrogen components to the emission dynamics was ranked the second. Our results suggest that ant nesting mediates the seasonal dynamics of soil methane emissions, primarily through changing the diversity of methane-function microorganisms and soil water conditions. The research results deepen the understanding of the mechanism of biological regulation of methane emission in tropical forest soil.

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.)

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] This paper aimed to explore the correlation between methane emission difference and root characteristics among different rice varieties. [Method] The six rice varieties from early to late rice were used for water culture experiment to observe the methane emission rate and root characteristics at different stages, and the correlation analysis was also made. [Result]There was significant difrence in methane emission rate among different early and late rice varieties. The highest methane emission rate was in Luliangyou 996, and the lowest was mid-early 39 in the whole growing stage, with a difference of 0.186 mmol·m-2s-1;The highest methane emission rate of late rice variety was Yuzhenxiang, and the lowest was Y Liangyou 1, with a difference of 0.282 mmol·m-2 s-1. There was a significant positive correlation between root oxidation capacity, root porosity and methane emission in early and late rice（P <0.05）, and a very significant negative correlation between methane emission rate and active absorption area and total root absorption area in early rice（P <0.01）. There was a very significant positive correlation between methane emission rate and active root absorption area and total root absorption area in late rice（P<0.01）. [Conclusion] The results showed that the root activity and root porosity were the key factors affecting the methane emission of rice. Among them, conventional early rice varieties and hybrid late rice varieties showed low emission characteristics, which provided a choice for planting rice varieties with low methane emission. [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.)

A pot experiment was conducted to investigate the effects of silicon supply on rice growth and methane (CH4) emission in paddy field under elevated UV-B radiation. The experiment was designed with two UV-B radiation levels, i.e. ambient UV-B (ambient, A) and elevated UV-B radiation (elevated by 20%, E); with four silicon supply levels, i.e., Si0 (control, without silicon), Si1 (as sodium silicate, 100 kg SiO2•hm-2) , Si2 (as sodium silicate, 200 kg SiO2•hm-2) and Si3 (as slag fertilizer, 200 kg SiO2•hm-2). The results indicated that, silicon supply obviously alleviated the depressive effect of elevated UV-B radiation on rice growth, and increased the tiller numbers, chlorophyll content, and shoot and root dry masses. Silicon supply promoted rice growth, which increased with the silicon supply level (sodium silicate). Slag fertilizer was better than sodium silicate in promoting rice growth. CH4 flux and accumulated CH4 emission were obviously increased by elevated UV-B radiation, but significantly decreased by silicon application. CH4 emission was reduced with increasing the silicon supply level. Under the same silicon supply level, slag fertilizer was better than sodium silicate in inhibiting CH4 flux and accumulated CH4 emission. This research suggested that fertilizing slag in rice production was helpful not only in utilizing industrial wastes, but also in significantly mitigating CH4 emissions in rice paddy under elevated UV-B radiation. [ABSTRACT FROM AUTHOR]

In a long term sitespecific experiment with rice straw return (RSR) and in a short term experiment with different RSR modes, this paper studied the effects of RSR on the soil organic car bon (SOC) sequestration, methane emission, and net carbon sink in a double season paddy field. RSR increased the SOC content, and the annual increasing rate of soil carbon sink in plow layer (0-15 cm) under long term RSR was 0.07 t C · hm-2 · a-1. With the increasing amount of RSR, the apparent SOC transformation rate decreased. RSR promoted the methane emission from the pad dy field significantly, and the methane emission flux in treatment RSR plus NPK during earlyand late rice growth seasons increased by 75. 0% and 251. 5% (P <0. 01), respectively, compared with that in treatment NPK. The methane emission increased with the increasing amount of RSR. Under the similar tillage mode and rice yield, the rice straw returned had the similar apparent methane transformation rate. Considering the soil carbon sequestration and the net carbon sink after methane emission in the paddy field comprehensively, treatment RSR plus NPK had significant negative effect on the carbon sink which was basically approached to the biofixation of carbon by rice and increased by 158.3%, as compared with treatment NPK. Among different RSR modes, rice straw mulching plus no tillage decreased soil methane emission significantly, with the net carbon sink decreased by 50. 9% as compared with the treatment high stubble plus tillage, and benefited the high and stable yielding of rice. [ABSTRACT FROM AUTHOR]

To explore the effects of different electron acceptors on soil methane emission and responses of soil microorganisms to different light conditions, a strict anaerobic 20-day incubation experiment was conducted with eight treatments: darkness + Fe 3+ (DF); darkness + NO 3 - (DN); darkness +SO 4 2- (DS); darkness + distilled water (DCK); light + Fe 3+ (LS); light + distilled water (LCK). The changes of methane concentration in the anaerobic incubation flask and the variation of the abundance of bacteria, archaea, fungi and six soil functional genes were analyzed. Results showed that soil methane emission under NO 3 - (LN); light +SO 4 2- (LS); light + distilled water (LCK). The changes of methane concentration in the anaerobic incubation flask and the variation of the abundance of bacteria, archaea, fungi and six soil functional genes were analyzed. Results showed that soil methane emission under NO 3 - , SO 4 2- addition and control (CK) was significantly lower under light conditions than dark, except the Fe 3+ treatment. DN, DCK and LF treatments had the highest abundance of bacteria, fungi and archaea genes, respectively. The gene abundance of methanogenic mcrA , sulfate-reducing bacteria Dsr , and carbon-fixing CbbL O concentration, Eh, nitrate, and total C contents. Under dark condition, methane emission was positively correlated with archaea and pmoA genes abundance, and negatively correlated with other genes abundance. Under light condition, methane emission was negatively correlated with the abundance of soil microbe and functional genes. In general, methane emission under light condition was significantly lower than that under dark condition (except for the Fe Geo treatment). These results showed that it was helpful to reduce methane emission under light condition, but the increase or decrease of methane emission was closely related to the type of electron acceptors and the functional responses of soil micro-organisms.nosZ were significantly up-regulated in the LN, DCK and LCK, respectively. Results of Pearson correlation and RDA analysis showed that CH 4 emission was significantly positively correlated with CO 2 concentration, pH, ammonium-nitrogen, and total N contents, and negatively correlated with N 2 O concentration, Eh, nitrate, and total C contents. Under dark condition, methane emission was positively correlated with archaea and pmoA genes abundance, and negatively correlated with other genes abundance. Under light condition, methane emission was negatively correlated with the abundance of soil microbe and functional genes. In general, methane emission under light condition was significantly lower than that under dark condition (except for the Fe 3+ treatment). These results showed that it was helpful to reduce methane emission under light condition, but the increase or decrease of methane emission was closely related to the type of electron acceptors and the functional responses of soil micro-organisms.