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ANALYSIS OF haBITAT PATTERN ChaNGE OF RED-CROWNED CRANES IN THE LIAO HE DELTA USING SPATIAL DIVERSITY INDEX

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Chinese Geographical Science 2003年第2期13卷 164-170页

作者： WANGLing LIXiu-zhen HUYuan-man GUODu-fa CollegeofPopulation ResourcesandEnvironmentShandongNormalUniversityJinan250014P.R.China InstituteofappliedEcology ChineseAcademyofSciencesShenyang110016P.R.China CollegeofLandandEnvironment ShenyangAgriculturalUniversityShenyang110161P.R.China

habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SDhabitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands.

关键词： spatial diversity Index red-crowned crane ( GrUS japonensis) habitatpattern the liaohe delta

Effect of Fertilization on Soil Fertility and Wheat Yield of Dryland in the Loess Plateau

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Pedosphere 2005年第2期15卷 189-195页

作者： haOMing-De faNJun WEIXiao-Rong PENLin-fa LAILu InstituteofSoilandWaterConservation ChineseAcademyofSciencesYangling712100（China） StateKeyLaboratoryofSoilErosionandDrylandfarmingontheLoessPlateau Yangling712100（China） CollegeofResourcesandEnvironmentalScience NorthwesternScienceandTechnologyUniversityofAgricultureandForestryYangling712100（China）

Long-term fertility experiments have become an important tool for investigating the sustainability of cropping systems. Therefore, a long-term (18-year) fertilization experiment was conducted in Changwu County, Shaanxi Province, China, to ascertain the effect of the long-term application of chemical fertilizers and manure on wheat yield and soil fertility in the Loess Plateau, so as to provide a scientific basis for sustainable land management. The experiment consisted of nine fertilizer treatments with thr…

关键词： dryland wheat yield long-term fertilization soil fertility

Detection of nitrogen-overfertilized rice plants with leaf positional difference in hyperspectral vegetation index

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第6期11卷 465-470页

作者： Qi-fa ZHOU Zhan-yu LIU Jing-feng HUANG College of Life Sciences Zhejiang University Hangzhou 310058 China College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

The main objective of this work was to compare the applicability of the single leaf(the uppermost leaf L1 and the third uppermost leaf L3) modified simple ratio(mSR705 index) and the leaf positional difference in the vegetation index between L1 and L3(mSR705L1-mSR705L3) in detecting nitrogen(N)-overfertilized rice plants.A field experiment consisting of three rice genotypes and five N fertilization levels(0,75,180,285,and 390 kg N/ha) was conducted at Xiaoshan,hangzhou,Zhejiang Province,China in *** hyperspectral reflectance(350-2500 nm) and the chlorophyll concentration(ChlC) of L1 and L3 were measured at different *** mSR705L1 and mSR705L3 indices appeared not to be highly sensitive to the N rates,especially when the N rate was high(above 180 kg N/ha).The mean mSR705L1-mSR705L3 across the genotypes increased significantly(Pha treatment and from 285 to 390 kg N/ha treatment at all the ***,use of the difference(mSR705L1-mSR705L3) greatly reduced the influence of the stages and genotypes in assessing the N status with re-flectance *** results of this study show that the N-overfertilized rice plants can be effectively detected with the leaf positional difference in the mSR705 index.

关键词： Rice Nitrogen (N) Overfertilization Leaf position Hyperspectral reflectance

Development of new ionic gelation strategy： Towards the preparation of new monodisperse and stable hyaluronic acid/ β-cyclodextrin-grafted chitosan nanoparticles as drug delivery carriers for doxorubicin

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Frontiers of Materials Science 2018年第1期12卷 83-94页

作者： Amina Ben MIHOUB Boubakeur SAIDAT Youssef BAL Celine FROCHOT Regis VANDERESSE samir ACHERAR Laboratoire de Chimie Physique Macromoleculaire (LCPM) Universite de Lorraine-CNRS UMR 7375 1 Rue Grandville BP 2045154001 Nancy Cedex France Laboratory of Physical Chemistry of Materials (LPCM) Faculty of Sciences (UATL) BP 37G Laghouat 03000 Algeria Laboratory of Biomaterials & Transport Phenomena (LBTP) Quartier Ain D'Heb 26000 Medea Algeria Department of Chemistry Faculty of Sciences University Saed Dahleb of Blida (USDB) route de Soumae 09000 Blida Algeria Laboratoire Reactions et Genie des Procedes (LRGP) Universite de Lorraine-CNRS UMR 7274 1 Rue Grandville BP 20451 54001 Nancy Cedex France

In the present study, β-cyclodextrin-grafted chitosan nanoparticles （β-CD- g-CS NPs） were prepared using a new ionic gelation strategy involving a synergistic effect of NaCI （150 mmol/L）, 4-（2-hydroxyethyl）-1-piperazineethanesulfonic acid （HEPES, 10 mmol/L）, and water bath sonication. This new strategy afforded smaller and more monodisperse β-CD-g-CS NPs vs. the classical ionic gelation method. New ha8β-CD-g-CS NPs were also prepared using the above-mentioned strategy by adding hyaluronic acid （ha） to the β-CD-g-CS copolymer at different weight ratios until the ZP values conversion. The best result was obtained with the weight ratio of w（ha）：w（β-CD-g-CS） = 2：1 and furnished new spherical and smooth ha/β-CD-g-CS NPs. Furthermore, the stability of β- CD-g-CS NPs and ha/β-CD-g-CS NPs at 4℃ in physiological medium （pH 7.4） was compared for 3 weeks period and showed that ha/β-CD-g-CS NPs were more stable all maintaining their monodispersity and high negative ZP values compared to β-CD-g-CS NPs. Finally, preliminary study of ha/β-CD-g-CS NPs as carrier for the controlled release of the anticancer drug doxorubicin was investigated. These new ha/β-CD-g-CS NPs can potentially be used as drug delivery and targeting systems for cancer treatment.

关键词： β-cyclodextrin-grafted chitosan hyaluronic acid ionic gelation drugdelivery physicochemical parameters control

Environmental Problems From Tea Cultivation in Japan and a Control Measure Using Calcium Cyanamide

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Pedosphere 2006年第6期16卷 770-777页

作者： K. OH T. KATO LI Zhong-Pei LI fa-Yun Center for Environmental Science in Saitama Saitama 347-0115 （Japan） Jinenjou-no-kai NPO Shizuoka 451-0305 （Japan） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） faculty of Environmental Sciences Liaoning University Shenyang 110016 （China）

A field experiment, involving lime N (calcium cyanamide, CaCN2) fertilization as a control measure, was conducted to study environmental problems induced by long-term heavy N application in Japanese tea fields. Long-term tea cultivation caused serious soil acidification. Seventy-seven percent of the 70 tea fields investigated had soil pH values below 4.0, and 9% below 3.0, with the lowest value of 2.7. Moreover, excess N application in tea fields put a threat to plant growth, induced serious nitrate contamination to local water, and caused high nitrous oxide loss. Compared with the conventional high N application treatment (1100 kg N ha-1) without lime N, the low N application (400 kg N ha-1) with calcium cyanamide effectively stopped soil acidification as well as achieved the same or slightly higher levels in tea yield and in total N and amino acid contents of tea shoots. The application of calcium cyanamide could be a suitable fertilization for the prevention of environmental problems in tea cultivation.

关键词： calcium cyanamide nitrous oxide emissions soil acidification tea cultivation water contamination

The Impact of US and CGIAR Germplasm on Maize Production in China

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Agricultural Sciences in China 2006年第8期5卷 563-571页

作者： LI hai-ming HU Rui-fa ZhaNG Shi-huang Zhanjiang Normal University Zhanjiang 524048 P.R.China Center for Chinese Agricultural Policy the Chinese Academy of Sciences Beijing 100101 China Institute of Geographical Sciences and Natural Resources Research the Chinese Academy of Sciences Beijing 100101 P.R.China Graduate School the Chinese Academy of Sciences Beijing 100094 P.R.China Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

Wide adoption of a few kinds of homogeneous germplasm would reduce crop genetic diversity, increase crop vulnerability to stresses, and reduce the stability of crop production. The introduction and utilization of foreign germplasm is a sustainable solution for broadening the genetic diversity and promoting periodical replacement of varieties. The genetic contribution and economic impact of foreign germplasm, particularly those of US and CGIAR （Consultative Group on International Agricultural Research, referred to as the CG system） materials, on China＇s maize production are evaluated on the basis of an analysis of variety pedigree information from 20 major maize-producing provinces in China from 1982 to 1997. The results indicated that the contribution of US and CG germplasm to Chinese maize production continues to increase, particularly CG germplasm, which has shown a rapid increasing trend since the 1990s. If the genetic contribution of US germplasm is increased by 1%, maize yield will gain by 0.2% （0.01 t ha^-1）. If contribution of CG germplasm, which has greater production potential, is increased by 1%, maize yield will gain by 0.025 t ha^-1. A policy should be implicated by the government in this direction to encourage breeders to focus more on the use and improvement of CG germplasm. The US germplasm has been utilized extensively in China so that it can offer germplasm resources for maize breeding efforts.

关键词： germplasm genetic diversity maize US CG

Ammonia Volatilization and Nitrogen Utilization Efficiency in Response to Urea Application in Rice Fields of the Taihu Lake Region,China

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Pedosphere 2007年第5期17卷 639-645页

作者： LIN De-Xi faN Xiao-Hui HU Feng ZhaO Hong-Tao LUO Jia-fa Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Department of Soil and Water Science Tropical Research and Education Center Institute of Food and Agricultural Sciences University of Florida Homestead FL33031 （USA） College of Resource and Environmental Sciences Nanjing Agricultural University Nanjing 210095 （China） College of Resource and Environmental Sciences Fujian Agriculture ＆ Forestry University Fuzhou 350007 （China） Land and Environmental Management Group AgResearch Ruakura Research Centre Private Bag 3123 Hamilton （New Zealand）

Ammonia volatilization losses, nitrogen utilization efficiency, and rice yields in response to urea application to a rice field were investigated in Wangzhuang Town, Changshu City, Jiangsu Province, China. The N fertilizer treatments, applied in triplicate, were 0 （control）, 100, 200, 300, or 350 kg N ha^-1. After urea was applied to the surface water, a continuous airflow enclosure method was used to measure ammonia volatilization in the paddy field. Total N losses through ammonia volatilization generally increased with the N application rate, and the two higher N application rates （300 and 350 kg N ha^-1） showed a higher ratio of N lost through ammonia volatilization to applied N. Total ammonia loss by ammonia volatilization during the entire rice growth stage ranged from 9.0% to 16.7% of the applied N. Increasing the application rate generally decreased the ratio of N in the seed to N in the plant. For all N treatments, the nitrogen fertilizer utilization efficiency ranged from 30.9% to 45.9%. Surplus N with the highest N rate resulted in lodging of rice plants, a decreased rate of nitrogen fertilizer utilization, and reduced rice yields. Calculated from this experiment, the most economical N fertilizer application rate was 227 kg ha^-1 for the type of paddy soil in the Taihu Lake region. However, recommending an appropriate N fertilizer application rate such that the plant growth is enhanced and ammonia loss is reduced could improve the N utilization efficiency of rice.

关键词： ammonia volatilization N application rate N utilization efficiency paddy soil rice yield

Additives on hydrogen donor catalytic upgrading for viscosity reduction of heavy oil under the conditions of steam injection

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Additives on hydrogen donor catalytic upgrading for viscosit...

Nitrogen Use Efficiency as Affected by Phosphorus and Potassium in Long-Term Rice and Wheat Experiments

The International Conference on Recent Trends in Materials and Mechanical Engineering(ICRTMME 2011)

作者： Zhao fa-jun Liu Yong-jian Zhang-bo ha-si Li Shi-ping Key Laboratory of Enhanced Oil and Gas Recovery of Education Ministry Northeast Petroleum University Post-Doctoral Scientific Research Station of Daqing Oilfield of Petro China Research Institute of Exploration and Development Daqing Oilfield Company Ltd

Under the simulated thermal recovery condition, fundamental experiments were carried out in the high temperature high pressure reactor to study the aquathermolysis reaction of heavy oil using formic acid as hydrogen donor and oil-soluble organic home-made nickel salt as catalyticUrea was selected optimally from the alternative chemical addictivess of ammonium carbonate, urea and ammonium hydrocarbonate and its dosage was 20wt%The affect of the adding addictives in water for viscosity, group composition and element content of heavy oil during the hydrogen donor catalytic pyrolysis reaction, was researchedIt was revealed that there mechanism in the heavy oil viscosity reduction reaction processThe addition of addictives had not only some degree of viscosity reduction function, but also synergistic interaction to the catalyzed reaction with hydrogen donorCompared to the oil sample from reaction without addictives, there was no obvious change on group compositions, the contents of atom C, H, S, N and O nearly kept unchangedthe introduction of addictives basically did not change structure of heavy oil.

关键词： Additives hydrogen donor heavy oil aquathermolysis catalytic upgrading

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Journal of Integrative Agriculture 2014年第3期13卷 588-596页

作者： DUAN Ying-hua SHI Xiao-jun LI Shuang-lai SUN Xi-fa HE Xin-hua Key Laboratory of Crop Nutrition and Fertilization Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Resources and Environment Southwest Agricultural University Institute of Plant Protection and Soil Science Hubei Academy of Agricultural Sciences Soil and Fertilizer Institute Sichuan Academy of Agricultural Sciences School of Plant Biology University of Western Australia

Improving nitrogen use efficiency （NUE） and decreasing N loss are critical to sustainable agriculture. The objective of this research was to investigate the effect of various fertilization regimes on yield, NUE, N agronomic efficiency （NAE） and N loss in long-term （16- or 24-yr） experiments carried out at three rice-wheat rotation sites （Chongqing, Suining and Wuchang） in subtropical China. Three treatments were examined： sole chemical N, N＋phosphorus （NP）, and NP＋potassium （NPK） fertilizations. Grain yields at three sites were significantly increased by 9.3-81.6% （rice） and 54.5-93.8% （wheat） under NP compared with N alone, 1.7-9.8% （rice） and 0-17.6% （wheat） with NPK compared with NP. Compared to NP, NUE significantly increased for wheat at Chongqing （9.3%） and Wuchang （11.8%）, but not at Suining, China. No changes in NUE were observed in rice between NP and NPK at all three sites. The rice-wheat rotation＇s NAE was 3.3 kg kg1 higher under NPK than under NP at Chongqing, while NAE was similar for NP and NPK at Suining and Wuchang. We estimated that an uptake increase of 1.0 kg N hal would increase 40 kg rice and 30 kg wheat ha-1. Nitrogen loss/input ratios were -60, -40 or -30% under N, NP or NPK at three sites, indicating significant decrease of N loss by P or PK additions. We attribute part of the increase in NUE soil N accumulation which significantly increased by 25-55 kg ha-1 yr1 under NPK at three sites, whereas by 35 kg ha-1 yr-1 under NP at Chongqing only. This paper illustrates that apply P and K to wheat, and reduce K application to rice is an effective nutrient management strategy for both the NUE improvement and N losses reduction in China.

关键词： apparent nitrogen balance grain yield nitrogen agronomic efficiency nitrogen loss soil nitrogen accumulation