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[Objective]The aims of this study are to investigate the spatial and temporal evolution characteristics of land use and ecological environment quality in the Three Gorges Reservoir area, to reveal the ecological environment effects caused by land use changes, and to provide a basis for land resource integration and ecological environment protection in the study area.[Methods]Remote sensing monitoring data of land use in 2000, 2010 and 2020 were selected to predict the spatial pattern of land use in 2030 under the Natural Change Scenario(NCS)and the Ecological Protection Scenario(EPS)using the CA_Markov model, respectively, and to quantitatively analyze the long time series of land use changes and ecological and environmental effects of the Three Gorges Reservoir Area by transfer matrix, ecological environment quality index, geostatistical analysis, and ecological contribution rate.[Results](1)From 2000 to 2020, the Three Gorges Reservoir Area had obvious transformation between land use types, in which cropland shifted to construction land, grassland shifted to forest land and cropland, and the growth of construction land area amounted to 1 321.56 km2, with a growth rate of 275.02％.(2)The simulation results show that the proportions of forestland and grassland area under the ecological protection scenario in 2030 will be higher than those under the natural change scenario, while the expansion of construction land significantly reduces compared with the natural change scenario.(3)The ecological quality of the Three Gorges Reservoir Area shows a stepped distribution pattern of gradual increase from west to east, and its ecological quality slightly decreases from 2000 to 2030, from 0.547 9 in 2000 to 0.533 6 in 2030.(4)From 2000 to 2030, the two dominant factors reducing the ecological quality of the Three Gorges Reservoir Area are the conversion of forests and grasslands to croplands, and the main favorable factor improving its ecological quality is the conversion of croplands to forests, with a proportion of ecological contribution exceeding 70％.[Conclusion]The return of farmland to forests and grasslands and rapid urban development have led to both ecological improvement and ecological deterioration in the Three Gorges Reservoir Area, but in general, the ecological environment quality in the study area shows a trend of improvement slightly less than deterioration, and the transformation between construction land, forestland, cropland and grassland is the main reason for this. [ABSTRACT FROM AUTHOR]

The landfill cover is the simplest and most feasible method to control methane emissions. Besides its low gas conductivity, methane emissions can be further reduced due to the methane oxidation by soil microbes. However, ordinary soil covers have poor engineering properties, and the methane oxidation efficiency of soil and microbial methane-oxidizing bacteria is low. Biochar is a carbon-rich, black, refractory solid material obtained through pyrolysis of biomass (such as peanut shells, wheat straw, sawdust, and rice straw) under oxygen-limited conditions. Due to its porous structure, high surface area, and pH characteristics, biochar applied to soil can change the microenvironment of the soil, which in turn can affect the efficiency of methane biological oxidation. To investigate the methane oxidation efficiency of biochar-methane oxidizing bacteria modified soil, methane detectors were used to measure the changes in methane reduction rates of both sterile and non-sterile soil samples under different pH levels, methane concentrations, soil dry densities, and biochar dosages. The results showed that when the pH of the inorganic salt culture solution was 7, the methane-oxidizing bacteria had high oxidation efficiency. The methane oxidation curve at pH value 7 is located at the bottom, indicating that the methane oxidizing bacteria have the optimal methane oxidation efficiency in neutral solution (i.e., at pH value 7). When the solution reaches alkaline properties at pH value 9, the methane reduction rate of methane oxidizing bacteria is significantly lower than that at pH value 7. This suggests that the growth, reproduction, and metabolic activity of methane oxidizing bacteria are inhibited in an alkaline environment, leading to a decrease in the efficiency of biological methane oxidation. At a certain initial methane concentration, the oxidation efficiency of methane-oxidizing bacteria increases with the increase of initial methane concentration, but when the initial methane concentration exceeds a certain value, it inhibits the oxidation efficiency of methane-oxidizing bacteria. In the control group experiment without the addition of bacteria, the slope of the curve is close to zero, indicating that the methane emission reduction efficiency is significantly lower in the sterile state compared to the condition with bacteria added. Both the biochar content and dry density affect the methane reduction efficiency of methane-oxidizing bacteria. The methane reduction amplitude with the addition of biochar is greater than that without biochar incorporation. The reason for this is that biochar has a porous structure and low density. When added to the soil, it increases the porosity of the soil and reduces its density, indirectly increasing the physical adsorption capacity of methane. Therefore, the methane reduction rate is more significant. Under the same conditions, the greater the dry density of the sample, the lower the oxidation efficiency of methane. With the increase in biochar content, the methane oxidation efficiency of biochar-methane oxidizing bacteria modified soil gradually increases. When the dry density and biochar content are 1.20 g/cm³ and 15%, respectively, the methane reduction rates under sterile and inoculated conditions show more significant decreases, being 10.38% and 39.72% respectively. This demonstrates that the addition of biochar has altered the microenvironment of the landfill cover soil, enhancing the methane oxidation efficiency of methanotrophs. This research holds significant academic and practical value for reducing greenhouse gas emissions from landfills, preventing air pollution, and promoting soil carbon sequestration. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department 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 China Condiment is the property of China Condiment 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.)

Alternate wetting and drying irrigation (IAWD) is one type of water-saving technology to repeatedly dry and re-flood the fields. However, the frequent alternate aerobic and anaerobic environment under IAWD has increased the reactive nitrogen gas emission in rice fields. Fortunately, biochar has been widely used to improve land productivity (including crop production, carbon sequestration, mitigation of GHG, and remediation of heavy metal pollution) in agricultural soil amendment. However, little information is available on the effects of biochar on NH3 volatilization, N2O emissions, and reactive nitrogen gas emissions in paddy rice systems, especially under IAWD. This study aims to explore the response mechanism of reactive nitrogen gas emissions to the biochar application under IAWD conditions. A two-year field split-plot experiment was conducted with the biochar application rates (0 and 20 t/hm² ) under two irrigation regimes (continuously flooded irrigation, ICF and IAWD). Two irrigation regimes were used as the main plots, whereas, two biochar additions were the subplots. Each plot was in the size of 3 m (width) × 6 m (length) that separated by the PVC barrier at a depth of 30 cm. in order to avoid the lateral flow of nutrients and water. The results showed that the IAWD increased yields by 1.7% to 5.1% (P>0.05), NH3 volatilization by 6.6% to 11.6%, and N2O emissions by 157.1% to 116.7%, compared with the ICF (P>0.05). Biochar addition at the rate of 20 t ha−1 significantly reduced the NH3 volatilization by 10.8% to 25.2% and N2O emissions by 21.6% to 24.2% (P>0.05). There was an increase in the yield by 0.2% to 12.5% and a reduction in the reactive nitrogen gas emissions by 6.1% to 11.7% in biochar combined with the IAWD, compared with the control (ICFB0). Furthermore, the inorganic nitrogen existed mainly in the form of NH4 + -N in the soil environment of rice fields, accounting for 80% to 90%. The IAWD had no significant impact on the soil NH4 + -N, compared with the ICF, whereas, a significant increase was found in the content of surface soil NO3 − -N by 50.3% to 74% and the oxidationreduction potential by 47.6% to 54.1% (P>0.05). Moreover, the biochar addition increased the soil NH4 + -N by 25.9% to 52.41% (P>0.05), and pH by 0.6% to 1%, compared with the biochar-free treatment. Principal component analysis showed a strong negative correlation between NH3 volatilization and soil NH4+ -N content, yield, and aboveground nitrogen accumulation. It indicated that the biochar addition significantly improved the soil adsorption capacity for the inorganic nitrogen, thereby reducing the NH3 volatilization losses and increasing aboveground nitrogen accumulation, ultimately leading to an increase in the yield. N2O emissions were strongly positively correlated with the oxidation-reduction potential and soil NO3 − -N. Therefore, the frequent alternate aerobic and anaerobic environment under IAWD increased the concentration of soil NO3 − -N and the oxidation-reduction potential, thereby increasing denitrification substrates and N2O emissions. Anyway, the biochar addition coupled with alternate wetting and drying can be expected to promote rice production with water saving, carbon sequestration and emission reduction, while reducing the environmental costs associated with the reactive nitrogen emissions in the paddy field. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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 Practical Medicine / Shiyong Yixue Zazhi is the property of Journal of Practical Medicine 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] In the present study, the rice cadmium-responsive gene OsGLP1-2 was cloned, and the bioinformatics and expression pattern analysis of Cd stress treatment were performed to provide a basis for exploring the molecular mechanism of OsGLP1-2 gene in response to heavy metal stress in rice. [Method] The OsGLP1-2 gene was cloned, and the characteristics of the gene and protein were analyzed by bioinformatics. Real-time fluorescent quantitative PCR (qRT-PCR) was used to analyze the expression pattern of OsGLP1-2 under Cd stress in rice stems and roots, respectively. At last, Cd tolerance analysis was performed using transgenic yeast. [Result] The cloned rice OsGLP1-2 gene coding region (CDS) sequence length was 651 bp, encoding 216 amino acids, the relative molecular weight of the encoded protein was 22.48 kDa, and the theoretical isoelectric point (PI) was 7.16, which was the stable and neutral hydrophobic protein, containing the Cupin domain and belonging to the Cupin family. The Cupin family played an important role in plant defense. The homologous family phylogenetic tree showed that this gene was a single branch, but it was the closest relative to HvGER5a in barley. It indicated that OsGLP1-2 may have similar functions as HvGER5a.The results of the secondary structure showed that the protein contained 10 β sheets, 8 α helices and 17 random coil structures. And OsGLP1-2 had regulatory elements related to environmental induction such as light and drought, as well as hormone-related regulatory elements such as auxin, gibberellin and methyl jasmonate, indicating that the target gene may participate in the response of rice to abiotic stress. Under the treatment of 100 μmol/L Cd, the expression level of the target gene in the above-ground part was about 3 times that of the control group at 6 hours, and the expression level of the underground part was also 3 times that of the control group, indicating that OsGLP1-2 gene could respond to Cd. Spot experiments showed that the gene had no obvious phenotype in yeast. [Conclusion] The rice OsGLP1-2 gene is successfully cloned, and the gene has a certain response to Cd, which can provide a reference for the response mechanism of rice to heavy metal stress. [ABSTRACT FROM AUTHOR]

Oryza sativa formin homology 1(OsFH1)plays a crucial role in rice root-hair growth and development, and the short root-hair phenotype of osfh1 was changed by environmental factors. However, the mechanism of how environmental factors interact with OsFH1 to regulate rice root-hair phenotype is still unknown. To determine whether OsFHs function in the process of osfh1 mutant root-hair phenotype recovery. The expression of OsFHs was analyzed by qRT-PCR in the osfh1 mutant treated under 1/2 MS liquid culture and 1/2 MS solid culture. Furthermore, qRT-PCR results were compared with bioinformatics analysis results. The results were as follows:(1)When compared with the wild type, osfh1 primary root showed a no root-hair. The osfh1 mutant showed a shorter shoot and more lateral roots. However, the no root-hair phenotype of osfh1 recovered under 1/2 MS solid culture treatment.(2)The expression of OsFH16 decreased and the expression of OsFH17 increased in the osfh1 mutant from liquid culture treatment to solid culture treatment with signifcant differences.(3)OsFH1, OsFH16 and OsFH17 all belonged to the Type Ⅱ subfamily, and all had cis-acting elements related to environmental stress, such as auxin, gibberellin, and anaerobic. OsFH1, OsFH16, and OsFH17 may be located in the plasma membrane to perform functions.(4)Analysis of the tissue-specific expression pattern of OsFHs showed that OsFH1 was highly expressed in the roots, while OsFH16 and OsFH17 were lowly expressed in the roots. In conclusion, this study suggests that OsFH1, OsFH16, OsFH17 have conservative structures and similar regulatory modes, and all three may function on the cell plasma membrane, therefore, OsFH16, OsFH17 may be involved in the process that environmental factors and osfh1 together alter the root-hair phenotype. Overall, this study lays a theoretical foundation for the mechanism research of environmental factors and osfh1 gene co-regulation of rice root-hair development and proposes a new direction for exploring the function of plant formin genes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. 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 Synthetic Crystals is the property of Journal of Synthetic Crystals 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 Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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 Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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 Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources 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 To observe the expression of angiomotin( AMOT), migration inducting gene-7( MIG-7), and matrix metalloproteinase 2( MMP-2) in the colon cancer tissues and to analyze their correlation with vasculogenic mimicry( VM). Methods Seventy patients with colorectal cancer underwent tumor resection, and cancer tissues and adjacent normal tissues were preserved during operation. Immunohistochemistry was used to detect the expression of AMOT, MIG-7 and MMP-2 in the cancer and adjacent tissues, and VM was detected by double staining to calculate the positive rate of VM. In addition, we analyzed the relationships of AMMOT, MIG-7, and MMP-2 with VM by Spearman. Kaplan Meier and Cox regression models were used to analyze the relationships between the clinicopathological parameters, AMOT, MIG-7, MMP-2, VM and the prognosis of colon cancer. Results The positive rates of AMOT, MIG-7, and MMP-2 were 58. 6%( 41/70), 61. 4%( 43/70), and 70. 0%( 49/70), in the cancer tissues, versus 31. 4%( 22/70), 0, and 4. 3%( 3/70) in the adjacent tissues, respectively. Compared with the adjacent control tissues, the positive rates of AMOT, MIG-7, and MMP-2 in the cancer tissues were higher( all P < 0. 05). The positive rate of VM in the colon cancer tissues was 32. 9%( 23/70). The expression of AMOT was correlated with the degree of differentiation and lymph node metastasis( both P <0. 05), and the expression of MIG-7, MMP-2, and the amount of VM were correlated with the degree of differentiation, depth of invasion, and lymph node metastasis( all P < 0. 05). There was a positive correlation between MIG-7, MMP-2 and VM in the colon cancer tissues( r = 0. 304 and 0. 259, respectively; all P < 0. 05). The degree of differentiation, depth of invasion, lymph node metastasis, and MIG-7 expression were related to the prognosis of colon cancer patients.Age, differentiation, lymph node metastasis, the expression of MIG-7, and VM were independent risk factors for prognosis of colon cancer. Conclusions AMOT, MIG-7 and MMP-2 are highly expressed in the colon cancer tissues, and the positive expression of VM is higher; MIG-7 and MMP-2 may affect the invasion, metastasis and prognosis of colon cancer by regulating the formation of VM in colon cancer. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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 Yellow River is the property of Editorial Board of Yellow River 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 Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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 Natural Resources / Ziran Ziyuan Xuebao is the property of Journal of Natural Resources 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 Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering 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.)