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Journal of Mountain Science 2013年第6期10卷 1074-1084页

作者： HUA Xiao-bo YAN Jian-zhong LIU Xiang WU Ying-ying LIU Lin-shan ZHANG Yi-li College of resources and environment Southwest University Institute of Geographic Sciences and natural resources Research Chinese Academy of Sciences

The implementation of pasture contracting policies in the Tibetan Plateau has been of widespread concern in the scientific community and related government departments. Studying the effects of the implementation of pasture contracting policies will help us understand herders' attitudes toward those policies and to amend existing policies *** paper analyzes 135 herder families' grazing management behavior using participatory rural appraisal(PRA), quantitative analysis and a Logistic regression model in three townships of Nagqu County in remote areas of the Tibetan Plateau, China. The results show that the herders have become settled and are no longer nomadic, so the settlement project has basically been completed and the policy of contracting for grazing rights is being gradually implemented in Nagqu County. Since the grazing rights and pastures were under contract, group-based management has been widely accepted in this area, which helps the herders deal with constraints, such as limited pasture area, a small grazing radius, controlled family animal husbandry and an uneven distribution of water. The herders that have more family members available for labor, higher proportion of family members with good health, and higher income from animal husbandry tend to choose household-based *** tend to choose group-based management when higher quality winter pastures are available.

关键词： Pasture contract Nagqu County Settledherders Participatory rural appraisal Tibetan Plateau

Evaluation and Optimization of Electrode Configuration of Multi-Channel Corona Discharge Plasma for Dye-Containing Wastewater Treatment

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Plasma Science and Technology 2015年第12期17卷 1053-1060页

作者：任景俞王铁成屈广周梁东丽呼世斌 College of natural resources and environment Northwest A&F University Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of Agriculture

A discharge plasma reactor with a point-to-plane structure was widely studied experimentally in wastewater *** order to improve the utilization efficiency of active species and the energy efficiency of this kind of discharge plasma reactor during wastewater treatment,the electrode configuration of the point-to-plane corona discharge reactor was studied by evaluating the effects of discharge spacing and adjacent point distance on discharge power and discharge energy density,and then dye-containing wastewater decoloration experiments were conducted on the basis of the optimum electrode *** experimental results of the discharge characteristics showed that high discharge power and discharge energy density were achieved when the ratio of discharge spacing to adjacent point distance（d/s） was *** Brilliant Blue（RBB） wastewater treatment experiments presented that the highest RBB decoloration efficiency was observed at d/s of 0.5,which was consistent with the result obtained in the discharge characteristics *** addition,the biodegradability of RBB wastewater was enhanced greatly after discharge plasma treatment under the optimum electrode *** degradation processes were analyzed by GC-MS and IC,and the possible mechanism for RBB decoloration was also discussed.

关键词： wastewater spacing ozone Configuration pollutant AOPs chemically Corona Fenton electrolysis

A spatial frequency/spectral indicator-driven model for estimating cultivated land quality using the gradient boosting decision tree and genetic algorithm-back propagation neural network

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International Soil and Water Conservation Research 2022年第4期10卷 635-648页

作者： Ziqing Xia Yiping Peng Chenjie Lin Ya Wen Huiming Liu Zhenhua Liu College of natural resources and environment South China Agricultural UniversityGuangzhou510642China

Cultivated land quality(CLQ)is related to national food *** and high-precision monitoring of CLQ is crucial for the sustainable development of ***,current satellite image-based evaluation methods that only consider the crop's spatial spectrum characteristics in the key growth stages cannot accurately estimate *** study proposes a new method based on time-series spectral data of crop growth to improve the accuracy of CLQ *** study was conducted in the Conghua District of Guangzhou,Guangdong Province,*** results showed that seven spectral indicators were determined as the optimal indicators based on the gradient boosting decision tree(GBDT)and variance inflation factor(VIF).And the genetic algorithm-back propagation neural network(GA-BPNN)model provided more accurate CLQ estimates than the partial least squares regression(PLSR)model,indicating a nonlinear relationship between CLQ and the *** addition,the GA-BPNN model with a normalized root mean square error(NRMSE)of 9.91%demonstrates the excellent potential for mapping CLQ over large *** model based on the seven optimal indicators of crop phenology provided higher accuracy than the GA-BPNN model based on the normalized difference vegetation index(NDVI)indicators in the spatial domain,significantly decreasing the NRMSE of the CLQ estimates by 3.17%.This further implied that the spectral indicators in the spatial frequency domain can improve the accuracy of estimating CLQ.

关键词： Cultivated land quality Time-series spectral data Spectral indicators Spatial frequency domain Conghua district

Behavioral differences within and among populations of an African cichlid found in divergent and extreme environments

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Current Zoology 2019年第1期65卷 33-42页

作者： Richard C. Oldham Lauren M. Pintor Suzanne M. Gray School of environment and natural resources The Ohio State University Columbus OH 43210 USA

Animals are increasingly faced with human?induced stressors that vary in space and time, thus we can expect populati on-level diverge nee in behaviors that help animals to cope with en vironme ntal change. However, empirical evidenee of behavioral trait divergence across environmental extremes is lacking. We tested for variation in behavioral traits among 2 populations of an African cichlid fish (Pseudocrenilabrus multicolor victoriae Seegers, 1990) that experience extremes of dissolved oxygen (DO) and turbidity and are known to vary in a number of physiological and life history traits associated with these stressors. Using a comm on garden reari ng experime nt, F1 progeny from wild-caught parents originating from a swamp (low DO, clear) and a river (high DO, turbid) were reared in high DO, clear water. Predator simulation assays were conducted to test for (1) variation in boldness, general activity, and foraging activity between populations,(2) differences in correlations betwee n behaviors with in and across populati ons, and (3) repeatability of behaviors. There was strong evide nee for diverge nee betwee n populati ons, with swamp fish being more bold (i.e.z leaving refuge sooner after a simulated predator attack) and active (i.e., spent more time out of refuge) than river fish. Across populations there were positive correlations between foraging activity and both boldness and general activity;however, within populations, there was only a strong positive relationship between foraging activity and boldness in the river population. Here, we have demonstrated that populations that originate from drastically different environments can produce proge ny that exhibit measurable differences in behaviors and their correlated relati on ships eve n whe n reared un der comm on conditions.

关键词： behavioral correlation behavioral syndrome boldness hypoxia pace of life turbidity

Potential production and spatial distribution of hybrid poplar as a biofuel crop in Connecticut,USA

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International Journal of Agricultural and Biological Engineering 2014年第2期7卷 10-18页

作者： Zhao Xue Liqin Qu Xiusheng Yang Department of natural resources and the environment University of ConnecticutStorrsCT 06269-4087USA

The objective of this study was to assess the biomass production potential from hybrid poplars using marginal lands in the state of Connecticut,USA.A land-use suitability model was developed to identify and classify marginal lands in the state that could be used for growing hybrid poplars as a biofuel woody energy *** model was built on a geographic information system(GIS)platform,consisting of an exclusion area section,an ecological suitability section,and an economic/land-use suitability *** model then was used to estimate the total biomass of the land-cover forests,annual biomass from forest and agricultural residues,and in particular the production potential of biomass from hybrid poplars over marginal lands in the state at county *** results indicated that about 50%of the land in this state is unavailable for hybrid poplar cultivation and that less than 5%is highly *** amount of usable area is highly variable on the county *** large-scale land use change,it appears that biofuel production in this state can only be a supplemental resource to the current energy supply.

关键词： biofuel plants hybrid poplar spatial distribution ethanol production Connecticut suitability model ecological suitability

Effects of Fe and Mn in Paddy Soils Derived from Different Parent Materials on Methane Production and Emission

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Pedosphere 2003年第4期13卷 337-344页

作者： LIU Ke-Xing, LIAO Zong-Wen, WANG Sheng-Chun and YOU Zhi-LinCollege of natural resources and environment, South China Agricultural University, Guangzhou 510642 College of natural resources and environment South China Agricultural University Guangzhou 510642 (China)

Three types of paddy soils, derived from granite, Quaternary red clay andbasalt, respectively, were selected to study the effects of Fe and Mn in paddy soils on methaneproduction and emission through pot and incubation experiments. The results indicated that thedifference of Fe and Mn in paddy soils was one of the important factors causing obvious differencesin methane emission from different soil types. Soil Fe and Mn affecting methane emission from thepaddy soils was likely through affectingsoil Eh and forming Fe and Mn plagues on rice *** rates and valences of added Fe and Mn significantly affected methane production from paddysoils. Therefore, this study enhanced understanding of processes controlling methane emission frompaddy soils and may help to improve modeling and estimating regional and global methane emissionfrom paddy soils.

关键词： Fe methane emission methane production Mn paddy soil

Changing institutions for environmental policy and politics in New Era China

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Chinese Journal of Population,resources and environment 2018年第3期16卷 242-251页

作者： Lei Zhang Xiaoran Li Department of environment and resources Management School of Environment and Natural Resources Renmin University of China

The evolution of Chinese environmental policy and politics can be better understood in the broader context of institutional changes that have taken place since the late 1970s. In this study,an analytical framework was established to analyze how overall institutional changes were reflected in the roles of relationships between governmental and non-governmental actors engaged in environmental governance. Institutional changes were observed at three levels:informal institutions(cultural traditions, and political ideology); formal institutions(the polity,political system, property rights, and judiciary); and governing mechanisms(structures, regulatory approaches, and incentives). This analysis of interactions between institutional changes and the changing environmental process explained not only the drives and constraints behind China's environmental policy evolution so far but also shed light on future challenges and opportunities.

关键词： Institutional changes environmental politics new environmentalism New Era China

Seasonal differences in sources and formation processes of PM2.5 nitrate in an urban environment of North China

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Journal of environmental Sciences 2022年第10期34卷 94-104页

作者： Yanli Li Yaping Geng Xiaomian Hu Xijie Yin Institute of resources and environment Henan Polytechnic UniversityJiaozuo 454000China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361000China

Nitrate(NO_(3)^(−))has been the dominant ion of secondary inorganic aerosols(SIAs)in PM_(2.5) in North *** the formation mechanisms and sources of particulate nitrate are vital to mitigate air *** this study,PM_(2.5) samples in winter(January 2020)and in summer(June 2020)were collected in Jiaozuo,China,andwater-soluble ions and(δ_(15)N,δ_(18)O)-NO_(3)^(−)were *** results showed that the increase of NO_(3)^(−)concentrations was the most remarkable with increasing PM_(2.5) pollution level.δ_(18)O-NO_(3)^(−)values for winter samples(82.7‰ to 103.9‰)were close to calculated δ_(18)O-HNO_(3)(103‰±0.8‰)values by N_(2)O_(5) pathway,while δ_(18)O-NO_(3)^(−)values(67.8‰ to 85.7‰)for summer samples were close to calculated δ_(18)O-HNO_(3) values(61‰±0.8‰)by OH oxidation pathway,suggesting that PM_(2.5) nitrate is largely from N_(2)O_(5) pathway inwinter,while is largely from OH pathway in *** fractional contributions of P_(N2O5+H2O) were 70% and 39% in winter and summer sampling periods,respectively,those of POH were 30% and 61%,*** δ_(15)N-NO_(3)−values for winter samples(3.0‰to 14.4‰)than those for summer samples(-3.7‰to 8.6‰)might be due to more contributions from coal combustion in *** combustion(31%±9%,25%±9%in winter and summer,respectively)and biomass burning(30%±12%,36%±12%in winter and summer,respectively)were the main sources using Bayesian mixing *** results provided clear evidence of particulate nitrate formation and sources under different PM_(2.5) levels,and aided in reducing atmospheric nitrate in urban environments.

关键词： PM_(2.5) Dual isotopes Nitrate formation pathways Bayesian mixing model

Dissolution of different zinc salts and Zn uptake by Sedum alfredii and maize in mono-and co-cropping under hydroponic culture

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Journal of environmental Sciences 2013年第9期25卷 1890-1896页

作者： Cheng'ai Jiang Qitang Wu Shucai Zeng Xian Chen Zebin Wei Xinxian Long College of natural resources and environment South China Agricultural University College of Forestry South China Agricultural University

Previous soil pot and field experiments demonstrated that co-cropping the hyperaccumulator Sedum alfredii with maize increased Zn phytoextraction by S. alfredii and decreased Zn uptake by maize shoots. This hydroponic experiment was conducted to investigate whether the facilitation of Zn phytoextraction by S. alfredii resulted from improved dissolution in this co-cropping system and its relation to root exudates. S. alfredii and maize were mono-and co-cropped （without a root barrier） in nutrient solution spiked with four Zn compounds, ZnS, ZnO, Zn3（PO4）2 and 5ZnO·2CO3·4H2O （represented as ZnCO3 ） at 1000 mg/L Zn for 15 days without renewal of nutrient solution after pre-culture. The root exudates were collected under incomplete sterilization and analyzed. The results indicated that the difference in Zn salts had a greater influence on the Zn concentration in maize than for S. alfredii, varying from 210-2603 mg/kg for maize shoots and 6445-12476 mg/kg for S. alfredii in the same order： ZnCO3 〉 ZnO 〉Zn3（PO4）2 〉 ZnS. For the four kinds of Zn sources in this experiment, co-cropping with maize did not improve Zn phytoextraction by S. alfredii. In most cases, compared to co-cropped and mono-cropped maize, mono-cropped S. alfredii resulted in the highest Zn2＋ concentration in the remaining nutrient solution, and also had a higher total concentration of low molecular weight organic acids （LMWOA） and lower pH of root exudation. Root exudates did partly influence Zn hyperaccumulation in S. alfredii.

关键词： zinc compounds dissolution co-cropping root exudates hydroponic

Interannual variations in salt flux at 80°E section of the equatorial Indian Ocean

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Science China Earth Sciences 2023年第9期66卷 2142-2161页

作者： Cuncun XIE Ruibin DING Jiliang XUAN Daji HUANG State Key Laboratory of Satellite Ocean environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Guangxi Key Laboratory of Beibu Gulf Marine resources Environment and Sustainable DevelopmentFourth Institute of OceanographyMinistry of Natural ResourcesBeihai 536015China Institute of Polar and Ocean Technology Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

The interannual variations in salt flux on the 80°E section in the equatorial Indian Ocean were explored based on the ORAS5 data,which was quite consistent with the observational data among the four available reanalysis *** results indicated that the area with significant interannual variations in salt flux coincided with that of significant climatological mean salt flux in general and was mainly located in the upper 150 m ***,three important areas were identified in the north-south direction,i.e.,(1)the Equatorial Indian Ocean Area(EIOA,3°S–3°N),where the mean salt flux was eastward with the largest value on the section and associated with the most significant interannual variations mainly modulated by the Wyrtki Jets and the Equatorial Undercurrent;(2)the South Equatorial Indian Ocean Area(SEIOA,3°S–6°S),where the mean salt flux changed in the vertical direction from strong eastward flux in the upper layer to weak westward flux in the subsurface layer and associated with significant interannual variations in the upper 100 m layer,which was affected by the South Equatorial Countercurrent;and(3)the North Equatorial Indian Ocean Area(NEIOA,3°N–6°N),where the mean salt flux changed in the north-south direction from strong westward flux to the north of 5°N to weak eastward flux in the south and associated with relatively significant interannual variations,which was mainly influenced by the South Sri Lanka Coastal *** leading interannual variation modes were revealed by the empirical orthogonal function *** first mode accounted for 39%of the total variance and had four significant spatial antinodes;two of those in-phase antinodes were located at SEIOA and upper 75 m of EIOA,and the other two opposite in-phase antinodes were located at NEIOA and below 75 m of *** second mode accounted for 17%of the total variance having four antinodes with two dominant out-of-phase antinodes located at the subsurface of EIOA and ***

关键词： Salt flux Interannual variation 80°E section Equatorial Indian Ocean Current