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Enclosure has been widely used in degraded grassland restoration as a brief and effective treatment, which changed microconditions of growth and production for plants. In the present study, the vegetation and the seed rain were investigated in enclosed and grazed plots after 8year enclosing on alpine meadow in the eastern Tibetan Plateau. The results showed that enclosure has significantly negative effects on species richness, Shannon index and individual density of vegetation, however, enclosure has significantly positive effects on richness and density of seed rain in enclosed plots compared with those in grazed plots. The changes of the numbers of Gramineae seeds played a key role in increasing of seed rain density. RAD (rank abundance distribution) displayed different patterns from enclosed plots to grazed ones. In enclosed and grazed plots, the pattern for seasonal dynamics of seed rain was unimodal. The Srensens similarity coefficient between seed rain and vegetation at fenced plots was higher than that at grazed plots, but the Srensens similarity coefficient between seed rain in enclosed plots and that in grazed plots was very high.
Soil properties under two conditions (fenced without grazing since 2002 and continuously grazed in the winter) were compared in the alpine meadow on QinghaiTibet Plateau. Under the two conditions, soil respiration rate, root biomass, soil water content, bulk densities, soil organic carbon and total nitrogen contents were compared and analyzed. The results showed that the soil respiration rate, bulk density and root biomass at the wintergrazed meadow were higher than those at the fenced meadow; while the soil water content, organic carbon and total nitrogen contents at the wintergrazed meadow were lower than those at the fenced meadow. Moderate grazing in the alpine meadow could increase the activities of soil microbes and accelerate mineralization and decomposition of soil nitrogen and organic carbon. However, appropriate exclusion of grazing can maintain soil nutrients and avoid loss of soil organic matter.
The simulation experiment with soil column was carried out to determine the effects of shortterm irrigation with reclaimed water on seasonal dynamic changes of microbial population in the root soil layer of greenbelt. The results of this study showed that the shortterm irrigation with reclaimed water increased the quantity of bacteria, fungus, actinomycete in soil when compared to clean water. The change of soil microbial quantity showed a single peak curve from May to November, and peaked in July or August. The differently changeable trends of soil microbial quantity were found in this study among six plants, which was possibly related to the biological characteristics of plants.
Carbon sequestration of four kinds shrubs in Ningxia was studied by testing leaf photosynthetic rate and plant biomass. The results indicated that if the research was on photosynthesis of each individual leaf, carbon sequestration was in the order of Buddleja alternifoliaAmygdalus mongolicaAtraphaxis bracteataLycium barbarum in the vigorous growth season (in July); or L.barbarumB.alternifoliaA.bracteataA.mongolica in the whole growth season. We also measured a singleleaf area, the area of whole plant leaves and the carbon sequestration of whole plant. The results indicated that sequence of the average daily amount of carbon assimilation of the whole plant was B.alternifoliaL.barbarumA.bracteataA.mongolica in both of the vigorous growth season and the whole growth season. The similar results were obtained on the measurement of biomass. Therefore, it can be concluded that the plant carbon sequestration in whole plant leaves should be considered if the photosynthetic rate is used as a testing target. In addition, it should be paid attention that there is a strong carbon sequestration of L. barbarum forests due to the good maintenance, such as irrigation and fertilizer.
Haloaylon ammodendron, Artemisia desertorum, Nitraria tangutorum and Ephedra przewalskii are widely distributed in Minqin desert, which are the major forages in this area. In the present study, we examined the functions of wind prevention and sandfixing of these plants. We calculated the vertical section per crown and the vertical section per unit area. We also calculated the volume of sand fixed by each crown and the volume of sand fixed per unit area. Then the functions of wind prevention and sand fixing of these plants were compared. The results showed that the function of wind prevention of a single crown was decreased in the following order: N.tangutorumH.ammodendronA.desertorumE.przewalskii. The function of sandfixing of a single crown was N.tangutorumE.przewalskii. The functions of wind prevention and sandfixing per unit area were decreased in the following order: N.tangutorumA.desertorumH.ammodendronE.przewalskii. If wind prevention is the main purpose, A.arenaria should be chosen. If sandfixing is focused, N.tangutorum should be chosen. If both of these functions are considered, N.tangutorum and A.desertorum will be a good choice.
In order to understand the impact of nongrazing on the services of typical steppe ecosystems quantitatively, the services of typical steppes under grazing and nongrazing with different periods (2 years, 7 years and 17 years) were evaluated. The result showed that nongrazing could raise the valuation of the services of typical steppe ecosystems, such as production, carbon sequestration, oxygen release, nutrient circle. The evaluation of production of typical steppes increased as the period of nongrazing increased, and that of the typical steppes with 17 years of nongrazing was highest. The evaluation of others, such as carbon sequestration, oxygen release, nutrient circle, is highest for typical steppes with 2 years of nongrazing. Nongrazing could improve services of typical steppe ecosystems, but nongrazing for a long time is not conducive to the improvement and maintenance of services of typical steppe ecosystems.
Turfgrasses always go through the process of droughtrewateringdroughtrewatering in the growth seasons. It is a good opportunity to examine the growth and morphology responses of turfgrass to drought stress and rewatering treatments. In this study, the responses of Barlexas cultivar of Tall Fescue (Festuca arundinacea) and Premier cultivar of Perennial Ryegrass (Lolium perenne) to drought stress and rewatering treatments were investigated. The results showed that drought stress caused a significant decline in TQ, leaf RWC, LWP, GR, ET, SWC and a significant increase in EL, LW of both cultivars. After rewatering, all the indicators rehabilitated to some degree. Leaf RWC, LW, LWP of both cultivars and TQ of Barlexas reached the same order of control group, however, EL, ET of both cultivars and TQ of Premier do not reached the order of control group. Through the entire experiment, Barlexas showed better performance than Premier, which suggests that Barlexas has a stronger drought resistance and recovery capability than Premier.
Microwave Vegetation Indices (MVIs) in the pastoral area of the south of Qinghai Province were calculated by using AMSRE brightness temperature data from 2007 to 2010 and its features of monthly MVI changes were discussed, and then the relationship between microwave vegetation index based on AMSRE data and vegetation index based on MODIS data for same time series was determined in this study. This study showed that the MVI value reduced as the vegetation plant grew and the MVIs was strongly negative correlations with NDVI and EVI, in which the correlation between MVIs and NDVI was the best with the correlation coefficient of 0.58. The optimal model between MVIs and MODIS vegetation indices wasNDVI=-0.85MVI+0.84, and the comparison result showed that the difference between MODIS NDVI and simulated NDVI from the optimal model was little. This study suggested that the optimal model reflected the relationship of the two vegetation indices.
Under the guidance of Integrated Orderly Classification System of Grassland (IOCSG), interpolation methods of Analytic Method based on Multiple Regression and Residues (AMMRR), in conjunction with DEM and meteorological data as main data source including annual accumulative temperature (), annual precipitation (r) of 113 stations in Gansu Province, were applied in spatial interpolation. Then the grassland classes in Gansu were classified through spatial overlay analysis. The results showed that the grasslands could be classified into 28 classes in whole province. Four classes with the largest area, i.e. ⅢA3 (Cool temperateextrarid temperate zonal desert), ⅢB10 (Cool temperatearid temperate zonal semidesert), ⅢE31 (Cool temperatehumid forest steppe，deciduous broad leaved forest) and ⅠF36 (Frigid perhumid rain tundra，alpine meadow), were distributed in north mountains, Hexi Corridor, Loess Plateau and Gannan Plateau. Meanwhile, four classes located in subtropics had the smallest area accounting for less 1%. The results also showed that the distribution of grassland classes fitted to the climatic characteristics of regions in Gansu. The interpolation of and r was closer to reality and the map of grassland classes could fully reflect the zonal patterns of grassland vegetation distribution, which proves that the AMMRR method has a better simulative result because the effect of topographic factors (longitude, latitude and elevation) to climatic factors was covered.
Grassland soil organic carbon pool becomes a focus in the field of grassland ecosystem in recent years due to the advance in the global climate change and transfer of carbon of the terrestrial ecosystems in various ways. Grassland soil organic carbon is an important component of the global carbon cycle, directly affecting on the global carbon balance. The impact of humaninduced climate warming resulting from the increase of greenhouse gases on grassland ecosystems arouses the considerable attention. Temperature, precipitation, atmospheric CO2 concentration, and other climatic factors greatly influence on the grassland soil organic carbon pool. Understanding the effects of climate change on the grassland soil organic carbon pool is critical for predicting the changes in grassland ecosystem carbon cycling in the future. This study summarized the advance in the distribution of organic carbon storage in the grassland soils and the effects of temperature, precipitation change, and elevated atmospheric CO2 concentration on grassland soil organic carbon storage, and then proposed the problems, direction and key field of grassland soil organic carbon in the future.
A practice of detecting chromosome ploidy levels in Dactylis glomerata and Lolium multiflorum by a flow cytometry method was reported; and aimed to discuss its application and reliability in forage polyploidy research. In order to investigate the chromosome ploidy levels of 4 D. glomerata germplasms (Wasemidori, PI316209, PI237602 and PI36880) and 3 L. multiflorum cultivars (Musashi, Tachimasari and Wasehope Ⅲ) by using the flow cytometry method, two known tetraploidy cultivars, including D. glomerata cv. Kitamidori and L. multiflorum cv. Mammoth B, were used as control materials. Their chromosome number in root tissue cells were double checked by the optical method and used to set a standard value in a flow cytometry. The results indicated that both of Wasemidori and PI316209 in D. glomerata were tetraploids, but PI237602 and PI36880 were diploids. For 3 tested L. multiflorum cultivars, Musashi was tetraploid, while Tachimasari and Wasehope Ⅲ were diploids. All chromosome ploidy levels of the tested cultivars or germplasms were confirmed to their known ploidy levels except of PI316209 in D. glomerata, which was a tetraploid instead of a diploid. The results provided a good reference to detect various chromosome levels in a same species by the flow cytomety method.
An orthogonal design was used to optimize a SRAPPCR system for Poa pratensis with 4 factors (Mg2+, dNTP, primer and Taq polymerase) at 3 levels plus the concentration of template DNA. The optimized SRAPPCR system was: 2 L 10 PCR buffer, 40 ng template DNA, Mg2+1.75 mmolL-1, dNTP 220 molL-1, primer 0.25 molL-1, Taq DNA polymerase 1.0 U in a total of 20 L reaction mixtures. With the optimized system, 43 primer combinations were selected among 100 primer combinations, which produced abundant polymorphism bands. This study optimized SRAPPCR system and selected the proper primers in P. pratensis, which would play an important role in genetic diversity analyses, map construction, germplasm identification in P. pratensis with SRAP markers.
Two pairs of degenerate primers were designed based on the conservative regions in amino acids of Cu/ZnSOD and Mn/FeSOD genes from other plants, respectively. Cu/ZnSOD gene fragment and Mn/FeSOD gene fragment of Camellia oleifera were cloned. Their sizes were 375 bp and 429 bp, respectively. By using the program of BLAST on NCBI GenBank database, two sequences presented a very high identity with Cu/ZnSOD and Mn/FeSOD genes from other plants. The nucleotide sequences were analyzed by using program of DNAStar 5.0. 125 amino acids and 143 amino acids were coded by the nucleotide sequences and the nucleotide sequences had the same conservative regions of Cu/ZnSOD and Mn/FeSOD genes as many kinds of other plants. The homology comparison of nucleotide sequences of Cu/ZnSOD gene and Mn/FeSOD gene showed the similarities of more than 80% and 84% to other plants, respectively. The similarities of amino acid sequences of Cu/ZnSOD and Mn/FeSOD genes were more than 84% and 86% to other plants.
A pot experiment was used to determine the Chlorophyll fluorescence characteristics of different position leaves in Lespedeza daurica under three different water level (80% FC, 60% FC and 40% FC) and two phosphorus treatments ( 0.1 Pgkg-1 dry soil and no P addition). The results of this study showed that the initial fluorescence (F0) and the maximum photochemical efficiency (Fv/Fm) of flag leaves were significantly lower those of middle leaves under moderate water stress and supply phosphorus, while there were no significant differences in maximal fluorescence (Fm), implying that the PSⅡreaction center of flag leaves were less destroyed than the middle leaf and the light energy transformation efficiency of flag leaves was higher. The leaf quenching coefficient (NPQ) significantly decreased and the Fv/Fm values of flag leaf and new leaf under moderate water stress condition were significantly higher in supply phosphorus treatment, indicating that the light energy dissipation decreased and light energy transformation increased under water stress by addition of phosphorus, which suggested that the supply phosphorus improved the adaptive capacity of L.daurica to semiarid loess hillygully region.
Anatomical observation was carried out on vegetative organs of Agropyron cristatum, including roots, stems, leaf and rhizomes, in this study. The results indicated that in order to adapt to a longterm external dry environment, the vegetative organs of A. cristatum formed droughtspecific morphological structures. The walls of endodermal cells of roots were thickened and the cells showed horseshoe shapes. The cortex cells near the endodermis systematically arranged in two rings, but cell walls were not thickened. The epidermal cells of stems arranged compactly and were horny thickening. Upper and lower epidermal cells of leaves had elldeveloped horny layers and vascular bundles; and the sheath of vascular bundles was a typical plant structure of C3. Rhizomes were consisted of epidermis, basic tissues and vascular bundles. The structure of rhizomes was similar to that of stems. The epidermal cells had no epidermal hairs and attachment structures. The vascular bundles distributed in the basic tissues, of which the vascular bundles near the epidermis arranged in a circle regularly but the others distributed irregularly.
The leaf ultrastructure of Potentilla sericea under water stress was investigated by transmission electron microscopy. The leaf photosynthetic rate (Pn), transpiration rate (Tr), stomata conductance (Gs), intercellular CO2 concentration and water use efficiency (WUE) were measured by portable photosynthesis system (LI6400). The results showed that the leaf ultrastructure was complete under control. Grana lamellaes of chloroplasts were distinct. The number of granas was abundant and the structure was compact. The thylakoids were compact and the grana stacks of thylakoids were regular. The chloroplasts showed lowly osmiophilic. There were few and small osmiophilic grain in the chloroplasts. With the intensive of drought stress, the grana and envelope damaged, the lamella swelled or dissolved and the grana stacks of thylakoids were disorder. Mitochondrial doublemembranes swelled or rived and its inclusion effused. The net photosynthetic rate was closely related to the change in chloroplast structure. The Pn, Tr and WUE of leaf decrease with the declining of soil water content and the damage of chloroplast.
17 morphological characteristic indexes and 11 nutritive elements of five different parts of Amorpha fruiticosa firstly planted in the QinghaiTibet Plateau (Lhasa, Maqu ) were investigated to understand the response of phenotypic plasticity and plant resource allocation of Amorpha fruiticosa to alpine habitat. The results of this study showed that phenotypic differences of A. fruiticosa was found in the two investigation regions, especially, the root morphological indexes were greatly different. The biomass proportion and nutritive element concentrations of different parts of A. fruiticosa was different between Lhasa region and Maqu region, which was caused by the response of plant resource allocation to alpine habitat. The correlation relationship between morphological indexes and nutrient element concentrations of A. fruiticosa was complex among two regions.
Eupatorium odoratum, which is a worldwide perennial invasive alien weed, usually spreads rapidly, and poses a serious threat to crops, forest, native vegetation and biodiversity. In order to understand characteristics of Chuomolaena odorata community structure in different habitats and its effects on plant species richness of native vegetation community, three C. odorata communities from different habitats were chosen for establishing three sample plots (plot A, B and C) in Longzhou county and Pingguo county of Guangxi. Plant species composition, structure characteristics, distributions of C. odorata and its effects on plant species richness of native vegetation in each plot were investigated and analyzed. The results showed that there were a total of 79 species, which belonged to 50 genera of 45 families, under the three habitats. The community structures were simple, including there layers (tree, shrub and herb) in plot A, two layers (shrub and herb) in plot B and C, but the plant species, quantity and vertical structure were different. Through the principle component analysis of 36 species with occurring frequency 10%, we found that the human disturbance and light condition were the key factors affected the C. odorata community structure, which contributed 42.88% and 24.17%, respectively. According to the two factors, all the samples could be divided into three cluster groups. The analysis of relationship between the importance value of C. odorata and plant species richness of the communities indicated that when the former reached to 0.51，the latter decreased with the rise of the former, which demonstrated a significant correlation between them. This study suggests that the invasion of C. odorata has an adverse effect on biodiversity, but the effect depends on the intensity of human disturbance.
Calorific value is one of the most important plant properties and is stabe normally. It is an important index on evaluating the plant primary productivity and plant nutrition, and also plays an important role in the process of ecology. In the researches of the plant calorific value, people paid much attention on just single plant species or some plant species grown in particular areas, but few people did some researches on largescales conditions.We collected the published papers about the plant calorific value in PSTP (http: //www. cqvip.com) from 1989 to 2010, classified and summarized the calorific values of 547 plants in 39 plots, which attempted to discuss the effects of plant organ，family，life form, longitude and latitude on plant calorific values based on the largescale conditions.The results showed that the order of calorific value of plants was Arborshrubherbaceous， which did not show a variation tendency with the changes of the plant species and distribution. The calorific values of blades of herbaceous and shrubs were the highest，while those of roots were the lowest. For arbor, the calorific value of shoots was the highest, that of roots was also the lowest. The calorific value of a family which had mainly herbaceous and shrubs was lower than that of the family with most of arbors. The study also indicated that Chenopodiaceae plants had the lowest calorific value; Ericaceae had the highest value. The calorific value of plants also increased with increasing latitude.
In order to monitor the different lots restoration of desert steppe and the influence of poisonous plant on enclosed steppe in Yanchi County of Ningxia Province, a piece of steppe with same restoration years and ways was chosen as an experimental field. Within the experimental field there were 4 plots being selected to investigate the vegetation according to growth of poisonous plants in each plot. Basic characteristics of communities were investigated by quadrat survey; and PCA sort method, correlation analysis and a linear regression model were used to analyze data obtained from the experimental field. Results showed that after 9 years of fencing, although composition species of communities did not change a lot, dominant species changed significantly in each plot; and there were different dominant species in different plots with different recovery rates. A large number of miscellaneous toxic grasses reduced the total cover of vegetation, species abundance, biomass of good forage and dominance of dominant species, so that the community structure presented simplificative and pasture growth patterns of clusters were promoted. The natural recovery process of grassland systems can not significantly control the growth and reproduction of poisonous plants, such as Cynanchum komarovii and Oxytropis aciphylla. Therefore, human being should give appropriate disturbance during the restoration of desert steppe.
The production performances of introduced 11 alfalfa （Medicago sativa） cultivars in NorthSichuan region of China were evaluated by using the comprehensive evaluation model of grey relevancy theory based on seven main indexes, including fresh forage yield, dry forage yield, the ratio leaf to stem, plant height, branch number, main root length and regrowing rate. A comprehensive evaluation model was established in the study. By analyzing the data using the model, the results showed that the order of weight of seven indexes was fresh forage yielddry forage yieldthe ratio of leaf to stemplant heightbranch numbermain root lengthregrowing rate. Cultivars of Hunter river, Hoopuland and WL323 had relatively good productive performances, while Afliter, Terry and Farmers treasure had poor performances. Although Emperor and Victoty had higher fresh forage yields, but the comprehensive evaluation scores were low because of their slower regrowing rate, lower ratio of leaf to stem and dry material contents.
A method of quadratic regression orthogonal rotation design was used to establish mathematical models for studying the relationships between seed yield of Phalaris tuberosa cv. Weining and five main cultivation factors (sowing rate, organic, nitrogen, phosphate and potash fertilizer) in 2008-2010. The results indicated that the order of the impact of various factors to the seed yield was the sowing ratenitrogen fertilizerorganic fertilizerphosphate fertilizerpotassium fertilizer. The analysis of twofactor interaction effects showed that the interaction effects between the seeding rate and nitrogen fertilizer; the seeding rate and the phosphorus fertilizer; or the nitrogen and the potassium fertilizer were more significant ot the seed yield. The optimum cultivation conditions for seed production of P. tuberosa cv. Weining were: sowing rate 3.75 kghm-2, organic fertilizer 7 500 kghm-2, nitrogenous fertilizer 450 kghm-2, phosphate fertilizer 750 kghm-2 and potash fertilizer 450 kghm-2. The highest seed yield was obtained at 449.50 kghm-2.
In order to study the effects of sheep management patterns on farmers income, ten households were selected in semi agricultural and semi pastoral area in Wuahaoling Mountain. In each household there were at least 30 pregnant ewes with 3yearsold and the body weight of these ewes were similar. Sheep from five households were fed in pen in cold season, which were classified in test group. At the same time, sheep from the other five household grazed in day and got supplementary feeding in the evening, which were classified in the control group. The results showed that the ewes' weights of two groups decreased by 1.17 and 2.71 kg after the lambs born one month, respectively. Then the body weights of test group started to recover and they gained 0.68 kg on average at the end of three months after the lambs were born. However, for the control group, they continued to lose body weight. At the end of three months after the lambs born, these ewes lost their weight by 5.96 kg on average, which accounted for 13.91% of the original weight. The born weight of lambs between two groups had no significant difference, but average daily gain of the test group was significantly higher than that of the control group, and the lambs body weights of test group in two months and at the sale time were significant higher than the control group (P0.05). Farmers' income of the test group was 20.27 Yuanewe-1 higher than that of the control group.
Australia is well known for good development for its animal husbandry. This paper give a brief introduction of the development of animal husbandry in Australia, and we also discussed the characteristics, current situation and related policies of its development. We focused our analysis on the measures that Australia has taken to achieve the sustainable development of its animal husbandry. Learning from the experience of Australia, we made some suggestions on the future development of animal husbandry in China.
Plants saponins were widely distributed in nature and rich in resources, which had huge research values and exploitation prospects because of their multiple biological activities. This review summarized the structure, biological activity and application in animal production of plant saponins, which will provide necessary information for improving the research work in the future. Keywords: saponin; biological activity; application
The Minxian County locates at the intersection area of the Qinling Mountains, Loess Plateau and QinghaiXizang Plateau. After discussing on the current situation of grass industry in the Minxian County, this study pointed out that the grassland degradation, extensive management of pasture, and shortages of processing technology of the grass products were the main problems in the development of grass industry; and proposed that the classification management for grass industry was future trend of grass industry in Minxian County. Finally, this study proposed the development strategies of grass industry in Minxian County, including that it was necessary to establish the grassland ecological compensation fund, develop the grass tourism, increase the productivity of pasture, improve the utilization of grassland resources and train the talent farmers.