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River systems originating from Qilian Mountains have been supporting the existence of the mountain-oasis-desert ecosystem in the Hexi corridor. However, the productive pressure and the global climate change put this ecosystem into a crisis. The integration of forest, herbage, shrub, and moss play a key role in the protection of quantity and quality of water source as well as in the conservation of ecological environment in Qilianshan Mountains. The mountains, oasis and desert take effects as a whole. Out of order of any of which would cause a disaster of the agricultural system. Based on the theory of Four Production Level of Paratacultural System, optimization of productive structure will take a shortcut of system coupling of mountainoasisdesert, which establishes the agricultural system for water resource conservation the agricultural system foundation. The kind of pattern supplies a demonstration for inner land area of the whole world.
Forest soil organic carbon (SOC) is the largest organic carbon pool in terrestrial ecosystem. It is of great significance for the carbon balance of the earth. The content of SOC, soil organic carbon density (SOCD) and relationship between influence factors of two naturally grown forests, Pinus tabulaeformis f. shekannesis and Quercus liaotungensis, and an artificially planted forest, P. tabulaeformis, were studied in Ziwuling forest area of the Loess Plateau. The means of SOCD were 10.76, 11.43 and 9.38kg/m2, respectively. SOCD decreased significantly as soil depth increased (P0.05). SOCD in three forests was different significantly. SOCD in the whole soil profile was positive correlated significantly with soil moisture，TN, TP, potassium and AN, but negative correlations with soil pH value.
The objective of this research was to compare the ecologic and economic benefit of Pi Te apple (Pyrus ussuriensis)-alfalfa (Medicago sativa) and wheat (Triticum aestivum)-alfalfa complex ecosystem in Linxia, Gansu Province. Soil bulk density was 1.39 and 1.45 g/cm3, noncapillary porosity was 4.72% and 4.15%, and overall porosity was 58.96% and 50.80%, respectively. Soil holding water capacity in the first ecosystem was higher than that in the second. Waterholding rate in leavesstems of alfalfa and wheat was 37.3% and 25.8%. Income in the first ecosystem was more than the second. These indicate M.alfalfa are more beneficial to the soil conservation and economic development than wheat in the apple ecosystems.
In order to protect wild resources of Saposhnikovia divaricata, effects of plant litter and soil burial on seedling emergence and early growth was investigated. Soil burial increased 8.45% of emergence percentage, 15.29% of survival and 1.72 mg of biomass, and also increased leaf number and plant height; Emergence percentage and seedling survival increased as the weight of plant litter increased, in which the survival increased one time compared with the control. However, more than 100 g/m2 of plant litter would decrease plant height and biomass. Therefore, 50100 g/m2 of plant litter were ideal level for the growth. Overall, the optimal method for establishment of the plant likely to be buried with soil, and recovery of the plant seem to be enclosed but not to long period.
The physiological responses to soil lead contamination stresses at 3 000 mg/kg and 6 000 mg/kg were studied in a pot experiment for two turfgrasses species centipedegrass (Eremochloa ophiuroides) and seashore paspalum (Paspalum vaginatum). The results showed that there were significant differences between two turfgrass species under the two lead stress regimes. Under 3 000 mg/kg Pb2+ stress, the leaf chlorophyll content, Fv/Fm and osmotic potential in centipedegrass did not changed significantly, while the electrolyte leakage (EL) increase significantly at 12 d, and the leaf relative water content (RWC) decrease significantly at 24 d. The visual turf quality maintained above the acceptable level (6.0) throughout the experiment period though a significant decline occurred after 4 d. Under 6 000 mg/kg Pb2+ stress, all physiological indexes in centipedegrass changed significantly at 4 d, and plants died at 12 d. In contrast, under 3 000 mg/kg Pb2+ stress, seashore paspalum did not decreased in leaf Fv/Fm, osmotic potential and chlorophyll content, which were significant higher than the control at 12 d, 16 d, 24 d. There were no significant differences in EL and visual turf quality between 3 000 mg/kg Pb2+ treatment and the control. Although a significant decrease occurred in leaf RWC at 12 d, it recovered at 24 d. Under 6 000 mg/kg Pb2+ stress, chlorophyll content of seashore paspalum still maintained the control level. The EL increased significantly after 4 d, and the osmotic potential, RWC and Fv/Fm decreased significantly after 4 d, but they recovered to the control level at 12 d, 16 d, 20 d, and 20 d, respectively. Although visual turf quality was lower than the control, it still maintained above the acceptable level throughout the experiment period. These results indicated that seashore paspalum had the capacity to repair the Pb2+ injures under the 6 000 mg/kg concentration and lead tolerance was higher than centipedegrass.
Ornamental grass as a new kind of plantdesign materials has great value in the construction of city green spaces and ecological landscape. Ornamental characters of 13 species of ornamental grasses were evaluated using graycorrelation analysis based on the oversummering survive rate, the plant growing situation, ornamental character, inflorescence aesthetic feeling and leaf color. The results showed that seven ornamental grasses, Pennisetum alopecuroides, Imperata cylindrical cv.Red Baron, Phalaris arundinacea var. picta, Cymbopogon citrates, Cortaderia selloana cv.Silver Comet, Carex oshimensis cv.Vergold, Acorus gramineus cv.Ogon, were better in ornamental and landscaping effects as they keep steady ornamental values in summer and autumn. Some ornamental grasses, such as Miscanthus sinensis cv.Zebrinus, Cortaderia selloana, M．sinensis cv.Variegatus, M． Sinensis cv.Gracillimus, have a high ornamental values in autumn since they flower in that season. Festuca ovina var.glauca has a ornamental value in silverblue leaves in the early growing phase. Stipa tenuissima does not adapt to the conditions of Nanjing.
American Hybrid Bluegrass (Poa pratensis cv. Hybrid) is a highquality turfgrass newly introduced from America as high drought resistance, strong cold duration, slow growth rate, fast adaptability and normal reproduction in China. Relative holding water, free proline, malondialdehyde and soluble carbohydrate of the turfgrass were determined after establishment of turfgrass, compared with Park bluegrass (P. pratensis cv. Park), Saber Bluegrass (P. pratensis cv. Saber), Bugby Bluegrass (P. pratensis cv. Bugby), Farway Perennial Ryegrass (Lolium perenne cv. Farway), Legend Red fescue (Festuca rubra cv. Legend) and Houndog (F. arundinacea cv. Houndog). Relative holding water (85.56%) and malondialdehyde (MDA) (0.002 5 mol/g) were lowest (P0.01), and free proline (81.563 4 g/g) and soluble carbohydrate (4.506 3%) were highest (P0.01). This indicates that drought tolerance of American Hybrid Bluegrass was the highest.
Species composition and plant diversity within watershed were investigated at different habitat in semiarid loess hilly region during the process of vegetation restoration. The results show that the proportion of species to the total plant is as follow: perennial herbageannual herbageshrubtree. The importance of different plants in ecological function were shrub in sunny slope, trees and shrubs in halfshaded and halfsunny slope, and trees in shaded slope. No significant differences were found in the biodiversity between different artificial forests. The environmental condition in the study site is the key factor for biodiversity, and people's production activities are a negative factor for restoration of biodiversity.
Dynamic of the aboveground biomass and nutrients of perennial grassland sown in different time were measured in a Grain for Green area from July 15 to September 18,2008. The result showed that the aboveground biomass initially increased as the plants growing and then dropped during experimental stage, the maximum appeared from August 23 to September 18. The contents of crude protein, crude fat and crude ash decreased, and the contents of crude fiber increased from July 17 to September 18.
A conclusion for the status of ecoenvironment of Yangtze, Yellow and Yalu Tsangpo rivers source region was obtained after studying by field investigation and interview to local herdsmen. Nowadays, the grassland has degraded entirely. The main reason is overgrazing for longterms, followed by rats, freezing and thawing, and erosions by water and wind. Besides, human activities and global warming promote the speed of degradation. Strategies and some advices were proposed for protecting ecological system and sustainable development for four counties of this region.
The best experiment conditions, accuracy and precision for determining the microamounts of lead content in plant by microwaveheating GFAAS approach were studied. Results indicated that the best acid system is 5 mL HNO33 mL H2O22 mL HF, the best microwaveheating condition is under the state of power 600 W、temperature 180 ℃ and microwaveheating 15 min.The optimal working condition of Graphite Furnace is the dried 45 s under 90 ℃, cineration 20 s under 900 ℃, atomized temperature 1 400 ℃ and cleaned temperature 2 500 ℃.The limit of detection of this method was found to be 0.068 4 mg/kg，the relative standard deviation error were in the range of 1.2%-5.6%，and recoveries were in the range of 95.81%-100.09%．
Based on information of meteorological and data of brown patch (Rhizoctonia solani) of Agrostis stolonifera, three models were established as follows: 1): the model for infecting time is Y=1/[1+e（5.179+0.346T0.156RH）]; 2) the model for disease incidence is x＝36.057－2.65T+0.615RH；3) the model for disease index is y＝26.39－1.872T+0.394RH. The disease incidence (x) was significantly correlated with the disease index (y) as the formula: y=0.67x－1.303.
Estimation of Net primary productivity (NPP) in terrestrial ecosystems is center issue in the study of global change. NPP is the total carbon fixed by plant photosynthesis in a year. In recent years, remote sensing data were introduced into establishment of NPP model and practice estimation. This already has developed into a new study method and a new trend. The method makes a possibility to estimate NPP in regional or global scales with details from remote sensing technology. In this paper, study history of NPP, the advantages and disadvantages of Statistical climatecorrelation models, Ecosystem process models and Light utilization efficiency models were reviewed and compared. Characteristics and research progress of three types of spatialtemporal dynamic simulation model, CASA, CFIX and BIOMEBGC, were explained and analyzed. At the same time, some problems in NPP models were pointed out and studies in further were emphasized.
Phosphorus accumulation and distribution were studied on 2, 3, 4, 5 and 7yearold alfalfa. The results showed that content of phosphorus in aboveground parts decreased during the whole growing seasons except increased little in the late, and decreased as plant ages increased. Content of phosphorus increased as order as leaves, reproductive organs and stems in maturing stage. As the plants growing in a year, phosphorus in aboveground parts increased, while accumulation rates increased firstly and then decreased. Phosphorus in the matured tissues was 64.7% in stems, 23.7% in reproductive organs, and 23.7% in leaves in all ages. For different ages of plants, phosphorus increased in stems and decreased in leaves as ages increased. Percentage of phosphorus in 2yearold reproductive organs was highest, and in 7yearold was lowest.
In order to select high yield and quick growth of alfalfa cultivars used in south China，the yield components and dry matter of 8 weak fall dormancy alfalfa cultivars were studied in a winterfallow farmland in Nanjing. Dry matter yields of 8 alfalfa cultivars were 730.26-1 460.25 g/m2 determined by harvesting 2 times in next spring. Plant height，primary shoot number and crop growth rate are important factors in dry matter yield. At the first cutting，dry matter yield was positively correlated significantly with plant height, internode number per caulis, primary shoot number and crop growth rate. At the second cutting，dry matter yield was positively correlated with crop growth rate, plant leaf area, stem diameter, primary shoot number, plant height, growth rate of plant height and branch number. Four cultivars including WL414，WL525HQ，Siriver and Derby had high potential that would to be used in south China as higher dry matter yield resulted from more plant height, primary shoot number and crop growth rate.
Condensed tannins (CT) affect the quality of the forage greatly. Proper amount of CT could improve the utilization rate and the nutritional quality for the forage. Content of the CT was examined with vanillic aldehyde, and the Dihydroflavonol 4Reductase (DFR) activity was determined with realtime monitor method after fertilizing different level of nitrogen on legume forage, Chamaecrasta nictitans. The condensed tannins decreased as nitrogen level increased, from 14.78% to 1.14% in leaves, from 4.62% to 0.98% in stems. Change of DFR activity is similar to CT content. This implied that increase nitrogen fertilizer would decrease CT content, which is helpful to the quality of the forage.
The heat tolerance of twelve varieties of Lolium perenne was tested with the electrical conductivity method. A sigmoid response curve with Logistic equation existed between the rate of injured cells of leaves and treatment temperature. The semilethal temperature obtained by seeking the point of inflexion on the curve. The heat tolerance of six turfgrass varieties in the decreased order were Accent, Cutter, Pinnacle, Bartwingo, Premier and Fairway, and for six forage varieties in the decreased order were Yatsyn, Oupec, Nul, Tove, Polim and Eminent.
Study on phenophase and main economic character of 15 strains of Astragalus sinicus in Fujian indicated that 8 strains were midmaturing with good growth traits, and better than varieties from out of province in investigated indexes. These strains were 8410441,8324411,84471031,8428121,84341022,8487711,8454311 and Mingzi 6. Their forage yields were higher than Changde variety(introduced uariety) at full flowering stage. They would to be new varieties or good materials for breeding in further after verifying and large amount of seeds were produced.
High temperature is one of the limiting factors in alfalfa production, which induces a series of responses in physiology and morphology. Alfalfa in Henan Province usually aestivate or died because of the high temperature stress, which affects quality and yield of the forage greatly. The progress of identification methods and evaluation indexes for heat resistance of alfalfa were summarized in this paper.
Seasonal factors have significant influence on the production of grassland livestock industry in Qinghai Province. Accurate understanding of seasonal utilization of grassland is of great importance for the scientific reasonable macromanagement of livestock production. Natural factors played a key role in the seasonal utilization of grassland. However, there are increasing impacts from human activity in recent years. In this study the method to classify seasonal pastures was revised using the GIS technology with two factors including elevation and human population. With this method, the models of 8 regions of Qinghai province were constructed, and the accuracies and scales of the model map were adjusted, respectively. Finally, the accuracies of the map were 66.65%. This can reflect the real situation of utilization of seasonal pastures. The percentages of two seasonal grasslands were consistent with the percentage of traditional distribution.
To determine the effects of two commercial inoculums on ensiling characteristics and in vitro digestibility of Ruthenia medic silage, an experiment was conducted with three treatments and a CK and with three replicates using a randominized complete block design. The three treatments were LaLsIL Dry（LD） 0.001%, SG 0.1%)and SG 0.2%.The materials were fermented for 90 days and then the quality of silages was assayed. The results showed that content of butyric acid was low, and direct ensiled russian fenugreek was considered as excellent by the classification standard of Vscore. No significant change in fermentation quality and digestibility in vitro was found in the treatment with LD. Lactic acid, crude protein and IVDMD of the treatment with SG 0.2% increased (P0.05), but NH3-N decreased (P0.05). The results indicated that SG enhanced the ferment ability of lactic acid bacteria, and depressed other microbe to decompose crude protein. It seems that digestibility of dry matter and crude protein in vitro decreased after fermentation.
Trifolium ambiguum was used as raw material at nutrition period after maturity. Six treatments were composed of 2 cm, 5 cm cutting, whole plant, with and without microorganism starter, with three replicates. These silage materials were bagged, crammed, sealed and ensilaged. The sensory evaluation and determination of nutritional components were carried out after 45 days. The treatment with 2 cm cutting and microorganism starter was better by sensory evaluation, at this time the alcohol flavor was strong, the color was yellow green, the leaves structure was good and the level of rotten was low. Based on nutritional components determination of T. ambiguum, crude protein content of the treatment with 2 cm cutting and microorganism starter was 20.25%, NDF and ADF were lower than the treatment of 2 cm cutting without microorganism starter. In a word, high moisture T. ambiguum silage had excellent effect, and silage quality of adding microorganism starter was better than direct silage. The objective of this study was to discuss the effects of silage methods on silage quality of T. ambiguum and to provide theoretical basis for efficient utilization of the grass.
Seven kinds of total mixed ration (TMR) feeds were prepared with corn stalks (control), corn stalks + Astragalus adsurgens+ alfalfa, corn stalks + Bromus inermis + Elymus nutan, corn stalks + Ceratoides arborescens + Lespedeza hedysaroides, corn stalks + alfalfa + Elymus nutans, corn stalks + alfalfa + Ceratoides arborescens, or corn stalks + Bromus inermis + Ceratoides arborescens. In each cornbread，oil cake of flax seed，bran and Efficient multidimensional calcium phosphate bone meal were added into. The result indicates pH value and the content of NDF in all of roughage decreased significantly, content of CP increased, and content of Ca and P varied little. In conclusion, fermentation quality of TMR made from these various roughages has been improved.
In order to standardize the testing method of germination of Indigofera pseudotinctoria seed, an experiment was conducted to determine the optimum condition for seed germination and accelerated aging test. In the germination test, the temperature treatments were adopted including 15-25 ℃, 15-30 ℃, 15-35 ℃, 20-30 ℃, 20-35 ℃, 25-35 ℃, 20 ℃, 25 ℃, 30 ℃ and 35 ℃, 2 light treatments(8 h lightness+16 darkness and 24 h darkness). In the accelerated aging trial, ageing temperature were 39 ℃, 41 ℃, 43 ℃, 45 ℃ and ageing duration were 24 h, 36 h, 48 h, 60 h, 72 h, 84 h, 96 h. The results showed that different combination of light and temperature treatments influenced germination rates of I. pseudotinctoria seed. Optimum conditions for seed testing of germination was constant temperature 25 ℃ or alternate temperature 20-30 ℃, 8 h light will be helpful for seedling growth, while total dark condition leads to the etiolated seedlings. There was an interaction effect between temperature and lightness. The first count time is the 7 th day after seed germination, and the last time is the 14 th day for the seedling evaluation. The optimal temperature of accelerated aging treatment was 43 ℃ and the ageing duration was 72 h and there was an interaction effect between accelerated aging temperature and duration.
Chicory (Cichorium intybus) is a perennial herb. It has been planted in most of countries in the world because it has high yield and excellent nutrients for livestock as forage. Its nutrition value in fresh is higher than alfalfa in crude protein, crude lipid, crude fiber, nitrogen free extract and ash. It takes advantages in strong tolerances to environmental stresses, long persistence, high productivity, rich mineral composition, and easy digestion. Therefore, it is used to establish pastures for harvesting foliage or grazing. In addition, it has wide use potential in medicine, beverage, food with special functions, and feed additive as it contains some natural substance.