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Modeling of Spatial Distributions of Farmland Density and Its Temporal Change Using Geographically Weighted Regression Model

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Chinese Geographical Science 2014年第2期24卷 191-204页

作者： ZHANG Haitao GUO Long CHEN Jiaying FU Peihong GU Jianli LIAO Guangyu college of Resources and environment Huazhong Agricultural University

This study used spatial autoregression(SAR)model and geographically weighted regression(GWR)model to model the spatial patterns of farmland density and its temporal change in Gucheng County,Hubei Province,China in 1999 and 2009,and discussed the difference between global and local spatial autocorrelations in terms of spatial heterogeneity and *** showed that strong spatial positive correlations existed in the spatial distributions of farmland density,its temporal change and the driving factors,and the coefficients of spatial autocorrelations decreased as the spatial lag distance *** models revealed the global spatial relations between dependent and independent variables,while the GWR model showed the spatially varying fitting degree and local weighting coefficients of driving factors and farmland indices(i.e.,farmland density and temporal change).The GWR model has smooth process when constructing the farmland spatial *** coefficients of GWR model can show the accurate influence degrees of different driving factors on the farmland at different geographical *** performance indices of GWR model showed that GWR model produced more accurate simulation results than other models at different times,and the improvement precision of GWR model was *** global and local farmland models used in this study showed different characteristics in the spatial distributions of farmland indices at different scales,which may provide the theoretical basis for farmland protection from the influence of different driving factors.

关键词： spatial lag model spatial error model geographically weighted regression model global spatial autocorrelation local spatial aurocorrelation

Effects of Long-Term Groundwater Management and Straw Application on Aggregation of Paddy Soils in Subtropical China

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Pedosphere 2015年第3期25卷 386-391页

作者： YIN Li-Chu ZHANG Lei YI Ya-Nan LUO Lan-Fang college of Resources and environment Hunan Agricultural University

Soil organic carbon （SOC） and iron （Fe）-oxides are important contributors of aggregate stability in highly weathered soils, and they are influenced by groundwater management and straw application. A 30-year plot experiment with early rice （Oryza sativa L.）-late rice-winter fallow rotations was conducted using a upland clay soil in cement pools under shallow groundwater table at a depth of 20 am （SGT） aud deep groundwater table at a depth of 80 cm （DGT） to simulate the groundwater tables of two types of important paddy soils, gleyed paddy soils and hydromorphic paddy soils, respectively, in subtropical China. Soil redox potential （Eh） was measured in situ, and 0-20 cm soil samples were collected for the analyses of soil Fe-oxides, SOC, and aggregates under SGT or DGT with different straw application treatments, in order to evaluate the interaction of groundwater management and straw application on paddy soil aggregation and the relative importance of SOC or Fe-oxides on soil aggregation. The results showed that soil Eh was restricted by irrigation, and its variation was more significant under DGT than under SGT. The decreased soil Eh or reduced drying and wetting cycles under SGT resulted in more SOC accumulation with the straw application, had no effect on soil free Fe-oxides （Fed）, significantly increased the amorphous Fe-oxide （Feo） and complex Fe-oxide contents, but decreased the crystalline Fe-oxide content （Fed-Feo）. The soils under DGT had more macroaggregates than those under SGT, but the difference decreased with the straw application. It could be concluded that soil Fe-oxides were the principal contributing factor to the aggregation of paddy soils in subtropical China and SOC was also an important contributing factor.

关键词： groundwater table Fe-oxides long-term experiment rice soil organic carbon

Timing of N Application Affects Net Primary Production of Soybean with Different Planting Densities

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Journal of Integrative Agriculture 2014年第12期13卷 2778-2787页

作者： ZHANG Ming-cong SUN Wen-xiang LIU Yuan-ying LUO Sheng-guo ZHAO Jing WU Qiong WU Zhen-yu JIANG Yi Resource and environment college Northeast Agricultural University

Understanding the relationship between the timing of N fertilizer applications and crop primary production is crucial for achieving high yield and N use efifciency in agriculture. This study investigated the effects of starting-N plus topdressing N applications （as compared to the common practice of all basal application） on soybean photosynthetic capacity under different planting densities. A ifeld experiment was conducted in two growing seasons （2011 and 2012）, and the soybean （Glycine max L. Merrill） cultivar was Dongnong 52, three planting densities （20, 25 and 30 plants m-2）, and four N fertilizer application patterns （all N fertilizer of 6 g N m-2 as basal fertilizer, all N fertilizer as topdressing at beginning pod stage （R3）, 1.8 g N m-2 as basal fertilizer and 4.2 g N m-2 as topdressing at stage R3 and full pod stage （R4）, respectively）. The results indicated that under the same planting density, compared to applying all N as basal fertilizer, the application of starter-N plus topdressing N substantially reduced the rate of pod abscission, and enhanced leaf area index （LAI） signiifcantly at beginning seed stage （R5）（P〈0.05）, net assimilation rate （NAR） during stages R4-full seed stage （R6）（P〈0.05）, contribution rate of post-seed iflling assimilate to seed （CPA）（P〈0.05）, and yield （P〈0.05）. Applying topdressing N at stage R4 resulted in higher net primary production and yield than applying topdressing N at stage R3. When applying starter-N plus topdressing N at planting density of 25 plants m-2, LAI after stage R5 and NAR after stage R4 were increased by 5.92-16.3%（P〈0.05） and 13.7-26.6%（P〈0.05） with the planting density of 20 plants m-2, respectively, and yield was 8.46-14.0%（P〈0.05） higher than that under 20 plants m-2. When planting density increased to 30 plants m-2, only LAI during stages R4-R5 and NAR during stages R4-R5 increased by applying starter-N plus topdressing N, while the other indexes declined. Overall, results of this study demonstrated

关键词： soybean starter-N plus topdressing N density leaf area index (LAI) net assimilation rate (NAR)

Epithelial-mesenchymal transition effect of fine particulate matter from the Yangtze River Delta region in China on human bronchial epithelial cells

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Journal of environmental Sciences 2018年第4期30卷 155-164页

作者： Yulang Chi Qiansheng Huang Yi Lin Guozhu Ye Huimin Zhu Sijun Dong Center for Excellence in Urban Atmospheric environment Institute of Urban Environment Chinese Academy of Sciences Key Lab of Urban environment and Health Institute of Urban Environment Chinese Academy of Sciences college of Resources and environment University of Chinese Academy of Sciences

Epidemiological studies have demonstrated that fine particulate matter（PM（2.5）） exposure causes airway inflammation, which may lead to lung cancer. The activation of epithelial–mesenchymal transition（EMT） is assumed to be a crucial step in lung tumor metastasis and development. We assessed the EMT effect of low concentrations（0, 0.1, 1.0, and 5.0 μg/m L）of PM（2.5） organic extract on a human bronchial epithelial cell line（BEAS-2 B）. PM（2.5） samples were collected from three cities（Shanghai, Ningbo, and Nanjing） in the Yangtze River Delta（YRD） region in autumn 2014. BEAS-2 B cells were exposed to the PM（2.5） extract to assess cell viability, invasion ability as well as the relative m RNA and protein expressions of EMT markers. Our findings revealed that BEAS-2 B cells changed from the epithelial to mesenchymal phenotype after exposure. In all groups, PM（2.5） exposure dose-dependently decreased the expression of E-cadherin and increased the expression of Vimentin. The key transcription factors, including ZEB1 and Slug, were significantly up-regulated upon exposure. These results indicated that the PM（2.5） organic extract induced different degrees of EMT progression in BEAS-2 B cells. The cell invasion ability increased in a concentration-dependent manner after 48 hr of treatment with the extract. This study offers a novel insight into the effects of PM（2.5） on EMT and the potential health risks associated with PM（2.5） in the YRD region.

关键词： PM2.5 BEAS-2B Epithelial–mesenchymal transition Cell invasion

Synthesis, Crystal Structure and Inhibition of N-2-Thiophenesulfonyl-α-L-phenylalanine Ethyl Ester on K562 Cell Proliferation

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Chinese Journal of Structural Chemistry 2007年第7期26卷 827-831页

作者：薛思佳申杰峰蔡志娟王庆东 college of Life and environment Science Shanghai Normal University

The title compound N-2-thiophenesulfonyl-a-L-phenylalanine ethyl ester has been synthesized. Complete assignments were achieved by IR, MS, ^1H NMR and single-crystal X-ray diffraction analyses. Using MTT assay, the inhibitory rate of the title compound on K562 cells （chronic myeloid leukemic cells） was measured and the result of preliminary bioassay showed that the title compound possesses antiproliferation effects on K562 cells. In order to investigate the relationship between structure and activity of the target compound, we report its crystal structure and biological behavior in the present paper. Crystallographic data： C15H17NO4S2, Mr = 339.42, monoclinic, space group P21, flack = -0.15（12）, a = 5.7916（10）, b = 11.5078（19）, c = 12.924（2） A, β = 97.781（3）°, Z = 2, V = 853.4（2） A^3, De = 1.321 g/cm^3, F（000） = 356, -7≤h≤7, -10≤k≤14, -15 ≤ l≤15, R = 0.0628, wR = 0.1540 and μ（MoKa） = 0.327 mm^-1. The molecule comprises a benzene and a thiofuran rings, and the intramolecular N（1）-H（1A）…O（1） makes a five-membered ring of O（1）--C（6）-C（5）--N（1）--H（1A）.

关键词： crystal structure N-2-thiophenesulfonyl-α-L-phenylalanine ethyl ester MTT assay

Assessing soil nitrous oxide emission as affected by phosphorus and nitrogen addition under two moisture levels

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Journal of Integrative Agriculture 2016年第12期15卷 2865-2872页

作者： Bashir Ullah Muhammad Shaaban HU Rong-gui ZHAO Jin-song LIN Shan college of Resources and environment Huazhong Agricultural University

Agricultural soils are deficient of phosphorus （P） worldwide. Phosphatic fertilizers are therefore applied to agricultural soils to improve the fertility and to increase the crop yield. However, the effect of phosphorus application on soil N2O emissions has rarety been studied. Therefore, we conducted a laboratory study to investigate the effects P addition on soil N2O emissions from P deficient alluvial soil under two levels of nitrogen （N） fertilizer and soil moisture. Treatments were arranged as follows： P （0 and 20 mg P kg-1） was applied to soil under two moisture levels of 60 and 90% water filled pore space （WFPS）. Each P and moisture treatment was further treated with two levels of N fertilizer （0 and 200 mg N kg-1 as urea）. Soil variables including mineral nitrogen （NH4＋-N and NO3--N）, available P, dissolved organic carbon （DOC）, and soil N2O emissions were measured throughout the study period of 50 days. Results showed that addition of P increased N2O emis- sions either under 60% WFPS or 90% WFPS conditions. Higher N2O emissions were observed under 90% WFPS when compared to 60% WFPS. Application of N fertilizer also enhanced N2O emissions and the highest emissions were 141 μg N2O kg-1 h-1 in P＋N treatment under 90% WFPS. The results of the present study suggest that P application markedly increases soil N2O emissions under both low and high soil moisture levels, and either with or without N fertilizer application.

关键词： phosphorus N2O emission water filled pore space nitrogen greenhouse gas

Theoretical Study on Thermodynamic Properties and Hydrophilicity of Polychorinated Phenothiazines (PCPTZs)

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Chinese Journal of Structural Chemistry 2011年第11期30卷 1575-1584页

作者：陈斌媛张学胜李定龙 college of environment and Safety Engineering Changzhou University

The thermodynamic properties of 135 polychlorinated phenothiazines （PCPTZs） in the standard state are calculated using a combination of quantum mechanical computations performed with the Gaussian 03 program at the B3LYP/6-311G^＊＊ level, and their octanol-water partition coefficients （logKow） are calculated based on group contributions. The chlorine substitution pattern strongly influenced the thermodynamic properties and hydrophilicity of the compounds. The thermodynamic properties of congeners also depend on the chlorine substitution pattern. The effect of chlorine substitution pattern is quantitatively studied by considering the mmaber and position of Cl atom substitution （Npcs）. The results show that the Npcs model may be used to predict the thermodynamic properties and hydrophilicity for all 135 PCPTZ congeners.

关键词： polyehlorinated phenothiazines density functional theory (DFT) number and position of Cl atom substitution (Npcs) thermodynamic property hydrophilicity

Recovery of cyanophycin granule polypeptide from activated sludge: carbon source dependence and aggregation-induced luminescence characteristics

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Frontiers of environmental Science & Engineering 2024年第2期18卷 25-34页

作者： Kui Zou Hongyuan Liu Bo Feng Taiping Qing Peng Zhang college of environment and Resources Xiangtan UniversityXiangtan 411105China

In the sewage treatment process,facilitating the conversion of pollutants into value-added resources holds great potential for reducing the amount of greenhouse gas emissions and promoting economic *** granule polypeptide(CGP),a recently discovered high value-added biopolymer present in activated sludge,has provided new avenues for the recovery of ***,the mechanisms that regulate CGP synthesis and the characteristics of this biopolymer in activated sludge remain unclear thus *** study investigated the synthesis of CGP,polyhydroxyalkanoates(PHA),and alginate-like exopolysaccharides(ALE)in various microbial aggregates under different carbon sources feeding *** results showed that the CGP yields was superior that of PHA and ALE when subjected to identical carbon source feeding ***,biofilm was more conducive to CGP accumulation than floc *** with glucose and methanol,sodium acetate significantly enriched the CGP synthetase-encoding gene(cphAabundance=~17419),resulting in the highest CGP yield(average 107.1 mg/g MLSS)in both biofilm and floc *** study is the first to reported the characteristic fluorescence of CGP(Ex/Em=~360/450 nm)caused by the aggregated luminescence of arginine on the side ***,this study highlights the potential application of CGP as a fluorescent material and offers insights into CGP recovery from activated sludge in wastewater treatment plants.

关键词： Cyanophycin Polyhydroxyalkanoate Alginate-like exopolysaccharides Bioresource recovery Aggregation-induced luminescence

A comparison of the toxicity of landfill leachate exposure at the seed soaking and germination stages on Zea mays L.(maize)

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Journal of environmental Sciences 2017年第5期29卷 206-213页

作者： Guangke Li Junyan Chen Wei Yan Nan Sang college of environment and Resource Shanxi University Taiyuan 030006 China

To compare the toxicity of landfill leachate exposure at the early stages of seed soaking and germination on maize,a field experiment was conducted to evaluate the physiological aspects of growth,yield and potential clastogenicity of root-tip cells. The maizes were treated with leachate at levels of 2%,10%,20%,30% or 50%（V/V）. First,the change of physiological indexes,including chlorophyll（Chl）,Malondialdehyde（MDA）and Reactive oxygen species（ROS）levels,combined with yield all showed that soaking with leachate,but not germination,generated a greater ecological risk on maize. After a soaking treatment of maize with 50% leachate,the Chl,MDA and ROS levels during a vigorous growth period were 47.3%,149.8% and 309.7%,respectively,of the control,whereas the yield decreased to 68.6% of the control. In addition,our results demonstrated that the leachate at lower levels could promote growth. This is mainly embodied in that the yield of maize treated with 10%leachate at the soaking stage increased to 116.0% of the control. Moreover,the cytological analysis experiment also demonstrated that the ecological risk of leachate still exists in both cases. Furthermore,the gray relational analysis showed that the ear row number and tassel branch number were the major factors affecting the yield of maize treated with 50%leachate at the stages of soaking and germination,respectively. In general,these results are helpful in understanding the phytotoxicity of leachate,which provides additional reference data for risk assessment and management of leachate.

关键词： Landfill leachate Maize Phytotoxicity Seed soaking Germination