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Sorption of Heavy Metal and Organic Pollutants on Modified Soils

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Pedosphere 2007年第2期17卷 235-245页

作者： MENG Zhao-Fu ZHANG Yi-Ping WANG Guo-Dong College of Life science Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 （China）. College of Natural Resources and the Environment Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 （China）

Sorption characteristics of both an organic pollutant (phenol) and a heavy metal (cadmium ion) on the clay layer of a Lou soil (Eum-orthic Anthrosol in Chinese Soil Taxonomy) along with the sorption mechanism were investigated using three soil treatments: modification with a cationic surfactant cetyltrimethylammonium bromide added at an amount equivalent to 5.% and 100% of the soil CEC (5.%CB and 100%CB), modification with an amphoteric surface-modifying agent dodecyldimethylbetaine (commercially known as BS-12) added at an amount equivalent to 5.% and 100% of the soil CEC (5.% BS and 100%BS), and an unmodified control (CK). Results showed that the BS soil treatments increased sorption of both the heavy metal Cd2+ and the organic pollutant phenol. The equilibrium sorption amount of Cd2+ decreased in the order: 5.%BS > 100%BS > CK > 5.%CB > 100%CB, with the BS soil treatments being about 1.3 to 1.8 times higher and the CB soil treatments about 23% to 41% lower than CK. Both the single-site and two-site Langmuir models could be applied to describe the sorption of Cd2+ in each soil treatment. The equilibrium sorption amount of phenol on the soil samples decreased in the order: 100%CB > 5.%CB > 100%BS > 5.%BS > CK, with the CB soil treatments being 41.0 to 79.6 times higher and the BS soil treatments 4.0 to 8.3 times higher than CK. The Freundlich equation could also be used to describe the sorption characteristics of phenol. In the BS soil treatments, both an organophobic long carbon chain and hydrophilic charged groups resulted in a relatively strong sorption ability for both heavy metals and organic pollutants. In addition, the sorption ratio K, the ratio of phenol sorption amount of the modified soil to that of CK, increased initially and decreased later with the amount of phenol added, and the critical sorption ratio KC, the peak value of the sorption ratio curve plotted against the added phenol concentration, was a good index for evaluating the sorption ability of

关键词： amphoteric surface modifying agent cadmium ion phenol sorption characteristics sorption ratio K

Soil Microbial Biomass Nitrogen and Its Relationship to Uptake of Nitrogen by Plants

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Pedosphere 2002年第3期12卷 251-256页

作者： ZHOUJIANBIN LISHENGXIU 等 CollegeofResourcesandEnvironmentalsciences NorthwestSci－TechUniversityofAgricultureandForestryYanglingShaanxi712100（China） CollegeofResourcesandEnvironmentalsciences NorthwestSci－TechUniversityofAgr

The contents of the soil microbial biomass nitrogen (SMBN) in the soils sampled from the Loess Plateau of china were determined using chloroform fumigation aerobic incubation method (CFAIM), chloroform fumigation anaerobic incubation method (CFANIM) and chloroform fumigation-extraction method (CFEM).The N taken up by ryegrass on the soils was determined after a glasshouse pot experiment. The flushes of nitrogen (FN) of the soils obtained by the CFAIM and CFANIM were higher than that by the CFEM, and there were significantly positive correlations between the FN obtained by the 3 methods. The N extracted from the fumigated soils by the CFAIM, CFANIM and CFEM were significantly positively correlated with the N uptake by ryegrass. The FN obtained by the 3 methods was also closely positively correlated with the plant N uptake. The contributions of the SMBN and mineral N and mineralized N during the incubation period to plant N uptake were evaluated with the multiple regression method. The results showed that the N contained in the soil microbial biomass might play a noticeable role in the N supply of the soils to the plant.

关键词： mineral N N uptake soil microbial biomass N

STUDY OF SETTING UP THE FOREST RESOURCES MANAGEMENT INFORMATION SYSTEM BASED ON WEBGIS

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Chinese Geographical science 2003年第1期13卷 56-61页

作者： WU Su-li, LOU Quan-sheng, QUAN Zhi-jie, LI Xiao-jun (northwest sci-tech university of agriculture and {5., Xi’an 712.00, P. R. china) northwest sci-tech university of agriculture and {5. Xi’an P. R. China

Based on an analysis of the characteristics of the Forest Resources Management Information System of each development phase, and consideration of the technical trend in Geographic Information System (GIS) in the Internet Age, this paper explores the importance and the feasibility of setting up Forest Resources Management Information System based on the WEBGIS. At the same time, based on the experience of our study, the paper explores the function, structure and method of developing the Forest Resources Management Information System based on WEBGIS. With the technology of WEBGIS, the Forest Resources Management Information System with data from Huoditang Farm was set up, which makes a great impact on forest resources management. So setting up the Forest Resources Management Information System based on WEBGIS is a trend of forest resources management. In the course of setting up this system, we must pay attention to following questions: 1) unify data standard and information encoding; 2) change mind.

关键词： WEBGIS forest resources management information system

Anatomy of Vitis Berries During Their Coloring

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Agricultural sciences in china 2002年第4期1卷 400-403页

作者： WAN Yi-zhen and HE Pu-chao(College of Horticulture, northwest sci-tech university of agriculture and {5., yangling 712.00 , P.R. china) College of Horticulture Northwest Sci- Tech University of Agriculture and Forestry Yangling 712100 P.R. China

During 1998 - 1999, the course of the berry coloring and the development of the pigment cells from veraison to ripeness were studied by freeze sectioning 43 accessions of 12 Vitis species (including 10 Chinese wild species). External observation showed that the berries of most species began coloring on the fruit top surface or on the sun-lit surface, and the berry surface color was evenly distributed when the berry was ripe. Internal observation revealed that the pigment cells in a few layers between cuticle and sub-cuticle colored first, the cuticle colored from inner layers to outer layers while the sub-cuticle from outer to inner, and the cuticle cells began coloring a little earlier than the sub-cuticle ones in most species. The pigment cells developed unevenly during the berry ripening. In the beginning of berry coloring, the cell pigment density among the layers or among the cells in the same layer was different. Both the numbers of the pigmented cells and the cell pigment density increased during the berry coloring, while the former lasted a short time; however, the latter kept increasing from veraison to ripeness, and they reached the deepest color when the berry was ripe.

关键词： Vitis Berry Coloring Pigment cell Anatomy

Origin of Gymnocypris przewalskii and phylogenetic history of Gymnocypris eckloni (Teleostei: Cyprinidae)

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Progress in Natural science:Materials International 2007年第05期17卷 520-528页

作者： Zhao Kai, Duan Ziyuan, Yang Gongshe, Peng Zuogang, He Shunping and Chen Yiyu (Institute of Hydrobiology, Chinese Academy of sciences, Wuhan 430072, china Laboratory of Animal Fat Deposition and Muscle Development, northwest sci-tech {5. of agriculture and forestry, yangling 712.00, china agriculture and Animal Husbandry College, Qinghai {5., Xining 810003, china Institute of Genetics and Developmental Biology, Chinese Academy of sciences, Beijing 100101, china) [a]Institute of Hydrobiology Chinese Academy of Sciences Wuhan China [b]Laboratory of Animal Fat Deposition and Muscle Development Northwest Sci-Tech University of Agriculture and Forestry Yangling China [c]agriculture and Animal Husbandry College Qinghai University Xining China [d]Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China

The origins and phylogenetic patterns were assessed for G. przewalskii and G. eckloni by analyzing the complete mtDNA cytochrome b gene sequence (1140bp). Phylogenetic analyses further supported that there were three mtDNA lineages (A-C) identified in G. przewalskii and G. eckloni, demonstrating that outer rakers of the first gill have little significance in the phylogeny of the Gymnocypris fishes. The network established showed that G . eckloni of the Yellow River specific haplotype Al was a founder and it radiated all haplotypes of G. przewalskii which suggested G . przewalskii might only originate from one of two maternals of G . eckloni from the Yellow River. Fs test and mismatch analysis showed at least two expansion events in the population of G. przewalskii about 0.2734 Ma and 0.065. Ma, while G. eckloni from Qaidam Basin could have experienced severe bottleneck effect about 0.0693 Ma. The population expansion was detected in subclades Al and A21 with the most recent common ancestor (TMRCA) about 0. 2308±0.01 Ma and 0.1319±0. 015.Ma, respectively, which were within the geological age range of "Gonghe Movement" event that caused the separation of Lake Qinghai from the upper Yellow River. These results suggested the effect of the fish diversification by rapid uplift of the Qing-hai-Tibetan Plateau in the Late Pleistocene.

关键词： G. przewalskii G. eckloni origin Cyt b phylogeography.

The Resistance of Chinese Wild Vitis to Uncinula necator and its Inheritance in F_1 Generation

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Agricultural sciences in china 2002年第2期1卷 195-199页

作者： ZHANG Jian-xia, WANG Yue-jin and XU Yan(College of Horticulture , northwest sci-tech university of agriculture and {5., yangling 712.00) College of Horticulture Northwest Sci-tech University of Agriculture and Forestry Yangling 712100

By natural field identification, the resistance of Chinese wild Vitis to Uncinula necator and its inheritance in F1 generation were studied with 35.clones of 9 Chinese wild Vitis species, 171 F1 individuals of 4 inter-species cross between Chinese wild Vitis and Vitis vinifera cultivars, and 16 individuals of self-pollinated Chinese wild Vitis. Results showed that the phenotypes of resistance to Uncinula necator in Chinese wild Vitis and its F1 generation were rich and diverse. Based on the segregation of resisitance to Uncinula necator in the progenies resulted from both interspecific hybridization and self-pollination, of Chinese native wild Vitis species and clones were controlled by poly genes showing dominant independent heredity. Minor resistant genes were also exist in Chinese wild susceptible Vitis species and clones.

关键词： Chinse wild Vitis F1 generation Uncinula necator Disease-resistance Inheritance

Developmental Tendency of Dry Land Farming technologies

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Agricultural sciences in china 2002年第8期1卷 934-944页

作者： SHAN Lun(Institute of Soil and Water Conservation, Chinese Academy of sciences and Ministry of Water Resources, northwest sci-tech university of {5. and forestry, yangling 712.00, P. R . china ) Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Northwest Sci- Tech University of Agriculture and Forestry Yangling 712100 P. R. China

The developmental tendency of dry land farming technologies in the semiarid area of china were reviewed based on the overview of recent progress in dry land farming researches from china and oversea. It was emphasized that conservation tillage, limited irrigation, genetic modification and chemical control are the important aspects for the dry land farming research and development of the future. In addition, some consid-

关键词： Dry land farming Conservation tillage Limited irrigation Genetic modification Chemical control

Low temperature wheat germplasm and its leaf photosynthetic traits and structure characteristics

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Progress in Natural science:Materials International 2004年第6期 21-26页

作者： ZHANG Songwu *, MIAO Fang and WANG Changfa(northwest sci-tech university of agriculture and {5.,yangling 712.00, china) northwest sci-tech university of agriculture and {5. Yangling 712100 China

Low temperature germplasm with constant low plant temperature was found in the nature through a long-time observation on wheat canopy temperature and traits;correspondingly,high temperature germplasm with constant high plant temperature also exists. Compared with the high temperature germplasm,the chlorophyll content and the net photosynthetic rate of the three functional leaves on the top of the low temperature wheat germplasm are higher and the structure tends to be more complicated,which is characterized by smaller mesophyll cells and more closely arranged cell layers,more and denser chloroplasts with thick stroma, more granas and well developed grana lamellae,a larger vascular bundle area with smaller interspace. All these characteristics embody the consistency of structure and function and provide the theoretical bases for looking for and cultivating the new low temperature materials in agricultural practice.

关键词： low temperature wheat germplasm leaf photosynthetic trait structure.

Effect of molecular weight of dissolved organic matter on toxicity and bioavailability of copper to lettuce

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Journal of Environmental sciences 2010年第12期22卷 1960-1965页

作者： Xudong Wang,Xianni Chen,Shuai Liu,Xizu Ge College of Resource and Environment,northwest agriculture and forestry university,Shaanxi 712.00,{5. [a] College of Resource Environment Northwest Agriculture forestry university Shaanxi 712100 China

To clarify the effects of molecular weight of dissolved organic matter （DOM） on the toxicity and bioavailability of copper （Cu） to plants, DOM extracted from chicken manure was ultra-filtered into four fractions according to their molecular weights by means of sequential-stage ultrafiltration technique. Lettuce seeds were germinated by being exposed to the solutions containing Cu^2＋ with or without different fractions of DOM. The concentration of copper in roots, leaves, sprouts and the length of roots were investigated. The results showed that not all fractions of DOM could improve copper availability or toxicity. The fraction of DOM with larger molecular weight more than 1 kDa had higher complexation stability with Cu^2＋ and caused lower concentration of free Cu^2＋ ion in the solution of copper plus the fraction, resulting in lower availability and toxicity of copper to lettuce, but the fraction with molecular weight less than 1 kDa had the opposite function. Therefore, the molecular weight of 1 kDa may be the division point to determine DOM to increase or decrease copper availability and toxicity.

关键词： fraction of dissolved organic matter complexation stability coooer availability