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Multifractal characteristics and spatial variability of soil particle-size distribution in different land use patterns in a small catchment of the Three Gorges Reservoir Region,China

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Journal of Mountain science 2021年第1期18卷 111-125页

作者： chen Tai-li SHI Zhong-lin wen An-bang YAN Dong-chun GUO Jin chen Jia-cun LIU Yuan chen Rui-yin Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China University of Chinese academy of sciences Beijing 100049China Department of Resources and Environmental Engineering Sichuan Water Conservancy Vocational CollegeChengdu 611231China

Characterizing soil particle-size distribution is a key measure towards soil *** purpose of this study was to evaluate the multifractal characteristics of soil particle-size distribution among different land-use from a purple soil catchment and to generalize the spatial variation trend of multifractal parameters across the catchment.A total of 84 soil samples were collected from four kinds of land use patterns(dry land,orchard,paddy,and forest)in an agricultural catchment in the Three Gorges Reservoir Region,*** multifractal analysis method was applied to quantitatively characterize the soil particle size *** soil particle size distribution(PSD)multifractal parameters(D(0),D(1),D(2),(3.)a(q),(3.)f[a(q)],α(0))were ***,a geostatistical analysis was employed to reveal the spatial differentiation and map the spatial distribution of these *** multifractal characteristics were *** trend of generalized dimension spectrum of four land use patterns was basically consistent with the range of 0.8 to ***,orchard showed the largest monotonic decline,while the forest demonstrated the smallest decrease.D(0)of the four land use patterns were ranked as:dry land3.,49.83.,0.84%,1.48%,22.20%and 10.60%,*** results showed that soil particles of each land use pattern were distributed *** multifractal parameters under different land use have significant differences,except forΔα(q).Differences in the composition of soil particles lead to differences in the multifractal properties ev

关键词： Land use patterns Purple soil Multifractal characteristics Particle size distribution Geostatistics Spatial variability

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Influence of Humic Acid on Interaction of Ammonium and Potassium Ions on Clay Minerals

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Pedosphere 2013年第4期23卷 493-502页

作者： ZHANG wen-Zhao chen Xiao-Qin ZHOU Jian-Min LIU Dai-Huan WANG Huo-Yan DU Chang-wen State Key Laboratory of soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Key Laboratory of Agro-Ecological Processes in Subtropical Region Institue of Subtropical Agriculture Chinese Academy of Sciences

Interaction of ammonium (NH+4) and potassium (K+) is typical in field soils. However, the effects of organic matter on interaction of NH+4 and K+have not been thoroughly investigated. In this study, we examined the changes in major physicochemical properties of three clay minerals (kaolinite, illite, and montmorillonite) after humic acid (HA) coating and evaluated the influences of these changes on the interaction of NH+4 and K+on clay minerals using batch experiments. After HA coating, the cation exchange capacity (CEC) and specific surface area (SSA) of montmorillonite decreased significantly, while little decrease in CEC and SSA occurred in illite and only a slight increase in CEC was found in kaolinite. Humic acid coating significantly increased cation adsorption and preference for NH+4, and this effect was more obvious on clay minerals with a lower CEC. Results of Fourier transform infrared spectrometry analysis showed that HA coating promoted the formation of H-bonds between the adsorbed NH+4 and the organo-mineral complexes. HA coating increased cation fixation capacity on montmorillonite and kaolinite, but the opposite occurred on illite. In addition, HA coating increased the competitiveness of NH+4 on fixation sites. These results showed that HA coating affected both the nature of clay mineral surfaces and the reactions of NH+4 and K+with clay minerals, which might influence the availability of nutrient cations to plants in field soils amended with organic matter.

关键词： adsorption illite kaolinite montmorillonite organo-mineral complex

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Effects of Extreme Air Temperature and Humidity on the Insecticidal Expression Level of Bt Cotton

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Journal of Integrative Agriculture 2012年第11期11卷 1836-1844页

作者： chenYuan wen Yu-jin chen Yuan John Tom Cothren ZHANG Xiang WANG Yong-hui WilliamA Payne chen De-hua Ecology and Cultivation in Middle and Lower Reaches of Yangtse River Ministry of Agriculture/Agricultural College Yangzhou University Yangzhou 225009 P.R.China Department of soil and Crop sciences Texas A&M University College Station TX77843 USA Key Laboratory of Crops Genetics and Physiology Jiangsu Province/Agricultural College Yangzhou University Yangzhou 225009 P.R. China Norman Borlaug institute for International Agriculture Texas A&M University College Station TX77843 USA

The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature （T） and relative humidity （RH） stresses in transgenic Bacillus thuringiensis （Bt） cotton. The unstable resistance of Bt cotton to bollworms has been correlated with the reduced expression of CrylAc δ-endotoxin. The objective of this study was to investigate the effects of combined temperature and relative humidity stresses on the leaf CrylAc insecticidal protein expression during critical developmental stages. The study was undertaken on two transgenic cotton cultivars that share same parental background, Sikang 1 （a conventional cultivar） and Sikang 3.（a hybrid cultivar）, during the 2007 and 2008 growing seasons at the Yangzhou University Farm, Yangzhou, China. The study was arranged with two factors that consisted of temperature （two levels） and relative humidity （three levels）. The six T/RH treatments were 3.℃/95%, 3.℃/70%, 3.℃/50%, 18℃/95%, 18℃/70%, and 18℃/50%. In 2007, the six treatments were imposed to the plants at peak flowering stage for 24 h; in 2008, the six treatments were applied to the plants at peak square, peak flowering, and peak boll stages for 48 h. The results of the study indicated that the leaf insecticidal protein expression in CrylAc was significantly affected by extreme temperature only at peak flowering stage, and by both extreme temperature and relative humidity during boll filling stage. The greatest reductions were observed when the stresses were applied at peak boll stage. In 2008, after 48 h stress treatment, the leaf Bt endotoxin expression reduced by 25.9-3..7 and 23.6-40.5% at peak boll stage, but only by 14.9-26.5 and 12.8-24.0% at peak flowering stage for Sikang 1 and Sikang 3. respectively. The greatest reduction was found under the low temperature combined with low relative humidity condition for both years. It is believed that the temperature and relative humidity stresses may be attribut

关键词： Bt cotton high temperature low temperature relative humidity CryIAc protein

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Effects of Hg and Cu on the activities of soil acid phosphatase

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2007年第7期8卷 1157-1163页

作者： XU Dong-mei chen Bo LIU wen-li LIU Guang-shen LIU Wei-ping institute of Environmental science Zhejiang University Hangzhou 310029 China Research Center of Environmental science Zhejiang University of Technology Hangzhou 310032 China

Comparative study on the activity and kinectic properties of acid phosphatase （ACPase） of three soils amended with Hg and Cu at constant temperature and humidity was carried out. The results indicated that the inhibition on ACPase of the three sample soils by Hg and Cu varied with the content of soil organic matter and pH, where, soil 1 was the most seriously contaminated due to its lowest content of organic matter and the lowest pH among three samples, soil 2 took the second place, and soil 3.was the least contaminated. Except soil 3. the activity of soil ACPase tended to increase along with the contact time under the same type and the same concentration of heavy metal. In particular the Vmax values of ACPase in all three samples decreased with increasing Hg and Cu concentration, whereas the Km values were affected weakly. According to the change of Vmax and Km values, Cu and Hg had the same inhibition effect on soil ACPase. Both of them may he a type of compound of non-competitive and anti-competitive inhibition. Statistic analyses indicated that activities of soil ACPase and Vmax values could serve as bioindicator to partially denote the heavy metal Hg and Cu contamination degree.

关键词： Acid phosphatase (ACPase). Activitv. Heavv metal. Kinetic propertv Sail

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Selected dark sides of biomass-derived biochars as environmental amendments

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Journal of Environmental sciences 2017年第4期29卷 13-20页

作者： Zien chen Lei Luo Diyi Xiao Jitao Lv Bei wen Yibing Ma Shuzhen Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences

With the rapid increase in the application of biochars as amendments, studies are needed to clarify the possible environmental risks derived from biochars to use safely the biomass resources. This work reported selected dark sides of maize straw-and swine manurederived biochars pyrolyzed at 3.0 and 500°C. During the pyrolysis processes, total heavy metals in the biochars were enriched greatly accompanying with considerable emission of the heavy metals into atmosphere and the trends became increasingly obvious with pyrolysis temperature. Meanwhile, the biochars showed distinctly decreased available heavy metals compared with raw feedstocks, which could be mainly attributed to the sorption by the inorganics in the biochars. The water-and acid-washing treatments significantly increased the releasing risks of heavy metals from biochars into the environments. Electron paramagnetic resonance analysis indicated that persistent free radicals, emerged strongly in the biochars as a function of the aromatization of biomass feedstocks, were free from the influence of water-, acid-, or organic-washing of the biochars and could remain stable even after aged in soils for 3. days. Dissolved biochars, highly produced during pyrolysis processes, showed distinct properties including lower molecular weight distribution while higher aromaticity compared with soil dissolved organic *** results of this study provide important perspectives on the safe usage of biochars as agricultural/environmental amendments.

关键词： Biochar Swine manure Heavy metal Free radical Dissolved biochar

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Single and joint effects of pesticides and mercury on soil urease

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Journal of Environmental sciences 2007年第2期19卷 210-216页

作者： YANG Chun-lu SUN Tie-hang HE wen-xiang ZHOU Qi-xing chen Su Key Laboratory of Environmental Engineering Shenyang University Shenyang 110044 China Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

The influence of two pesticides including chlorimuron-ethyl and furadan and mercury （Hg） on urease activity in 4 soils （meadow burozem and phaeozem） was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase （up to 13.-21%） in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship （P〈0.05） between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose （ED50） values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.

关键词： chlorimuron-ethyl furadan mercury soil urease combined pollution

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Decadal expansion and contraction of permafrost in the Three-River Source Region,Qinghaie-Tibet Plateau(1901-2020)

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Advances in Climate Change Research 2023年第2期14卷 226-236页

作者： Fang-Fang chen Dong-Liang LUO Yi-Ting GAO wen-Jie LEI State Key Laboratory of Frozen soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese academy of sciences Beijing 100049China

Permafrost and its spatiotemporal variation considerably influence the surface and sub-surface hydrological processes,biogeochemical cycles,fauna and flora growth and cold region engineering projects in the Three-River Source Region(TRSR),Qinghai–Tibet ***,the dynamics of permafrost over a relatively long term duration(e.g.>100 years)in the TRSR is not well ***,the spatial and temporal variations of the temperature at the top of the perennially frozen/unfrozen ground(TTOP),active layer thickness(ALT)in permafrost regions and the maximum depth of frost penetration(MDFP)in the seasonally frozen ground of the TRSR during 1901–2020 were simulated using the TTOP model and Stefan equation driven by the widely used reanalysis Climatic Research Unit 4.05 *** revealed that the permafrost in the TRSR over the past 120 years did not degrade monotonically but experienced considerable fluctuations in area with the decadal oscillations of climate warming and cooling:shrinking from 263.9×10^(3.km^(2)in the 1900s to 23..3.10^(3.km^(2)in the 193.s,expanding from 23..3.10^(3.km^(2)in the 1940s to 260.9×10^(3.km^(2)in the 1970s and shrinking again from 254.1×10^(3.km^(2)in the 1980s to 228.9×10^(3.km^(2)in the *** regional average TTOP increased from−1.3.±2.74℃in the 1910s to−0.48±2.69℃in the 2010s,demonstrating the most noticeable change for the extremely stable permafrost(TTOP3.0 m by 12%from 1901 to ***,minor changes were observed for the regional average MDFP,probably due to the increase in the area proportion of MDFP3.0 m(caused by climate warming)and MDFP>3.5 m(owing to the transformation of permafrost to seasonally frozen ground)by 7.3.%and 4.77%,*** findings can facilitate an in-depth understanding of permafrost dynamics and thus provide a scientific reference for eco-environment protection and s

关键词： Three-River Source Region Permafrost TTOP model Stefan equation Qinghaie-Tibet Plateau

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Occurrence and bioaccumulation of polybrominated diphenyl ethers in sediments and paddy ecosystems of Liaohe River Basin, northeast China

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Journal of Environmental sciences 2016年第5期28卷 250-256页

作者： Xindong Ma Haijun Zhang wenjun Yao wen Guo Depeng Li Ziwei Yao Jiping chen State Oceanic Administration Key Laboratory for Ecological Environment in Coastal Areas National Marine Environmental Monitoring Center Dalian institute of Chemical Physics Chinese Academy of Sciences School of Chemistry Engineering & Light Industry Dalian Polytechnic University

Concentrations of 16 polybrominated diphenyl ether（PBDE） congeners were measured in river sediments, paddy soils and three species of paddy-field organisms（crab, loach and carp） collected from the Liaohe River Basin, northeastern China. The total contents of PBDEs（∑_（16）PBDEs） in sediments and paddy soils were in the ranges of 273.4–3.46.3.pg/g dry weight（dw）, and 192.1–1783.8 pg/g dw, respectively. BDE 209 was the dominant congener both in sediments and paddy soils. The concentrations of ∑_（16）PBDEs in sediments were significantly higher than those in the adjacent paddy soils, indicating a potential transport of PBDEs from river to paddy ecosystems via river water irrigation. The biota–soil accumulation factor（BSAF） was calculated as the ratio between the lipid-normalized concentration in paddyfield organisms and the total organic carbon-normalized concentration in paddy soil. The average BSAF values of ∑15PBDEs followed the sequence of crab（3.6）〉 loach（3.3. 〉 carp（2.1）. BDE 154 had the highest BSAF value, and a parabolic trend between BSAF values of individual PBDE congeners and their log KOWvalues was observed. In view of the fact that crab had the larger BSAF value and higher lipid content, the ecological risk and health risk for crab cultivation in paddy fields should be of particular concern.

关键词： Polybrominated diphenyl ethers Bioaccumulation Sediment Paddy field Liaohe River Basin

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Effects of Climate Warming on Phenological Characteristics of Urban Forest in Shenyang City,China

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Chinese Geographical science 2016年第1期26卷 1-9页

作者： HE Xingyuan XU Sheng XU wenduo chen Wei HUANG Yanqing wen Hua State Key Laboratory of Forest and soil Ecology Institute of Applied EcologyChinese Academy of Sciences Northeast institute of Geography and Agroecology Chinese Academy of Sciences

Change in plant phenology is one of the most sensitive ecological responses to climate warming. Little information is known about the effects of climate warming on phenology of urban tree species in the northern forest of China. In this study, we investigated the phenological characteristics of the main tree species in the urban forest of Shengyang City in China and the correlation between phenology and atmospheric temperature from the discontinuous data during past 42 years over three time periods(from 1962 to 1965, 1977 to 1978, and 2000 to 2005). The results showed that the annual average temperature in Shenyang City showed an increasing trend and increased by 0.96℃ from 1962 to 2005 due to climate warming. The germination phenology of the urban trees was negatively correlated with the temperature in winter and early spring. The leafing phenology was mainly influenced by the temperature in spring before leafing. Influenced by climate warming, the germination, leafing, and flowering phenologies of this urban forest in 2005 were 14, 13. and 10 days earlier than those in 1962, respectively. We inferred that further warming in winter might prolong the growing season of urban trees in the northern forest of China.

关键词： global climate change global warming plant phenology urban forest Shengyang City

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Effects of land use change on the spatiotemporal variability of soil organic carbon in an urban-rural ecotone of Beijing,China

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Journal of Integrative Agriculture 2016年第4期15卷 918-928页

作者： YE Hui-chun HUANG Yuan-fang chen Peng-fei HUANG wen-jiang ZHANG Shi-wen HUANGShan-yu HOU Sen Key Laboratory of Digital Earth science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100094P.R.China Hainan Key Laboratory of Earth Observation Sanya 572029P.R.China College of Resources and Environment China Agricultural UniversityBeijing 100193P.R.China State Key Laboratory of Resources and Environment Information System Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijing 100101P.R.China College of Earth and Environment Anhui University of Science and TechnologyHuainan 232001P.R.China institute of Geography University of CologneKoln 50923Germany

Understanding the effects of land use changes on the spatiotemporal variation of soil organic carbon （SOC） can provide guidance for low carbon and sustainable agriculture. In this paper, based on the large-scale datasets of soil surveys in 1982 and 2009 for Pinggu District -- an urban-rural ecotone of Beijing, China, the effects of land use and land use changes on both temporal variation and spatial variation of SOC were analyzed. Results showed that from 1982 to 2009 in Pinggu District, the following land use change mainly occurred： Grain cropland converted to orchard or vegetable land, and grassland converted to forestland. The SOC content decreased in region where the land use type changed to grain cropland （e.g., vegetable land to grain cropland decreased by 0.7 g kg-1; orchard to grain cropland decreased by 0.2 g kg-l）. In contrast, the SOC content increased in region where the land use type changed to either orchard （excluding forestland） or forestland （e.g., grain cropland to orchard and forestland increased by 2.7 and 2.4 g kg-1, respectively; grassland to orchard and forestland increased by 4.8 and 4.9 g kg-1, respectively）. The organic carbon accumulation capacity per unit mass of the soil increased in the following order： grain cropland soil〈vegetable land/grassland soil〈orchard soil〈forestland soil. Therefore, to both secure supply of agricultural products and develop low carbon agriculture in a modern city, orchard has proven to be a good choice for land using.

关键词： land use change soil organic carbon spatiotemporal variability urban-rural ecotone

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