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2009 Vol.26(7)

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2009, 3(7): 1-1.
[Abstract](1338) [PDF 155KB](1606)
2009, 3(7): 2-2.
[Abstract](1203) [PDF 136KB](1722)
2009, 3(7): 3-5.
[Abstract](1012) [PDF 479KB](1516)
The dynamic change research of ecological environment in Longbao region of Yushu state in Qinghai
2009, 3(7): 6-11.
[Abstract](1533) [PDF 859KB](728)
The study selected the areas of 9 252 km2 in Longbao region of Yushu state in Qinghai and 15 years remote sensing image data from 1990 to 2004. The correlation between changes of ecological environment in Longbao region under the scale of climate change and climate factors was analyzed by means of evidence analysis and gray correlation analysis. The results showed that the ecological environment of Longbao region was in an obvious instable condition, the transformation of ecological types was remarkable, the area of lake and marsh which were the most representative factors of the wetland ecotype had been reduced, and the reducing rate of marsh was 487.3 hm2/a. The area changes of different ecological types such as rivers, marshes, transit area of shrub grassland and unsuitable forest grassland were more correlative with temperature, and lakes were more correlative with temperature and frozen earth, other waters were more correlative with temperature and evaporation, grassland and uncovered rock were more correlative with temperature and precipitation, permanent snow or glaciers were more correlative with temperature, evaporation and frozen earth. The grassland suitable for forestry and shoal were all associated with precipitation, evaporation and the frozen earth. The shrubbery ecotype was only correlative with frozen earth.
Comparative research on habitat of main plant community in desert grassland in Minqin
2009, 3(7): 12-18.
[Abstract](1721) [PDF 664KB](687)
The study selected 4 kinds of main eremophytes communities in Minqin and conducted comparative research in terms of habitat and niche. The results indicated that 1)differences of soil composition mainly demonstrated in 0.05 mm soil particle of 4 kinds of communities such as Artemisia arenaria, Nitraria tangutorum, Ephedra przewalskii and Haloxylon ammodendron. 0.251.00 mm coarse sand were rich in A. arenaria and E. przewalskii communities, 1.0 mm gravel was dominant in E. przewalskii soil, 0.05~0.25 mm fine sand were the most in N. tangutorum soil. Total Nitrogen content was higher in H. ammodendron than other 3 communities. 2) The niche breadth of the dominant species was the biggest in the community, the niche breadth of H. ammodendron was the biggest, followed by E. przewalskii, N. tangutorum had the smallest. 3) The habitat conditions of A. arenaria and A. squarrosum and Calligonum ongolicum were approximately the same, Bassia dasyphylla, Agriophyllum squarrosum, Halogeton arachnoideus and N. tangutorum had similar habitat, and the habitat conditions were close in N. sphaerocarpa and E. przewalskii.
Design of monitoring and management system of returning grazing to grassland project in Gansu
2009, 3(7): 19-23.
[Abstract](1499) [PDF 885KB](735)
The project of returning grazing to grassland was an important ecological project in areas owned large areas of grassland of North China. Based on the requirement of construction and management of returning grazing to grassland project in Gansu, using the professional tools such as ArcGIS, ArcSDE, MapObject, Access/Oracle, ERDAS Imagine Develop Kit, Visual C++/Delphi and so on, a monitoring and management system was designed, which was consisting of the information input subsystem, the project monitoring and evaluating subsystem, the spatial operation and analysis subsystem, the information retrieval subsystem and information output subsystem. It could reflect the construction progress and quality of the project objectively and comprehensively, assess the influence of the project on the regional environmental and social economy and its change tendency, and provide the information and the basis for decisionmaking for animal husbandry production and ecology construction.
Research on dynamic estimation models of grassland based on MODISNDVI in the middle section of northern hillside of Tianshan Mountain
2009, 3(7): 24-27.
[Abstract](1350) [PDF 408KB](745)
Taking the grassland in middle section of the northern hillside of Tianshan Mountain as a typical study area, this research utilized EOS/MODIS satellite remote sensing data to process the dynamic monitoring of biomass change of grassland. The article analyzed the spatiotemporal change characteristic of vegetation index, as well as the correlativity between NDVI and aboveground biomass with MODIS vegetation index, consequently established the MODISNDVI of biomass dynamic estimation model in different seasons at mountain meadow grassland, mountain grassland and mountain desert grassland. The result indicated that the optimal dynamic yield estimation models of three types of grassland were the linear regression model, quadratic curve regression model, and the power function curve model, and their yield estimation accuracy reached 83.06%, 90.85%, 88.06%, respectively.
Remote sensed monitoring of lake dynamic change based on MODIS image
2009, 3(7): 28-31.
[Abstract](1483) [PDF 825KB](760)
250 m250 m EOS/MODIS satellite information between 2005 and 2008 was pretreated and geometrically adjusted. Water area of Barkol Lake was calculated by using C++ program and remote sensed monitoring data was obtained by every ten days. The results showed that with the seasonal change of temperature and rainfall, the area of Barkol Lake varied accordingly. The lake was frozen from November to March and thawed after. The first maximum value of lake area was occurred in May or June, which was caused by snow melting; the second maximum value was observed in July or August, which was caused by the rainfall.
Study on alkalinity resistance of alfalfa callus in mutagenic treatments
2009, 3(7): 32-35.
[Abstract](1723) [PDF 461KB](666)
The stem of alfalfa(Medicago sativa)was used as the experimental material, the inducement of callus was conducted, and the callus of alfafa was treated by ultraviolet ray and NaN3. Callus in mutagenic treat and control were filtrated by proline and forced alkalinity stress by NaHCO3 and Na2CO3, then they were appraised by the alkalinity resistance physiological indexes such as peroxidase activity, soluble protein content and proline content. It was shown that all these three indexes in the treated callus were evidently higher than those in the control. So the method of ultraviolet ray and NaN3 could be used to improve the alkalinity resistance of alfalfa, and ultraviolet ray treatment had greater effect on the alkali resistance of alfalfa than NaN3 treatment.
Preliminary study on variation characteristics of photosynthetic rate in Radix Pseudostellariae
2009, 3(7): 36-39.
[Abstract](1561) [PDF 793KB](685)
In order to prove up the variation characteristics of photosynthetic rate in Radix Pseudostellariae. Under the proper condition of sunny day, Li6400 portable photosynthesis system was used to study the diurnal and different growth periods variation in photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gc) of the top second leaf in R. pseudostellariae. The results showed that the curves of diurnal variation in photosynthetic rate of R. pseudostellariae represented single peak type, and it did not exhibit the midday depression phenomena.The photosynthetic rate and transpiration rate of R. pseudostellariae. were depended on the stomata conductance in great extent, and both were extremely significantly positive correlated(P0.01)with the stomata conductance. The photosynthetic rate and transpiration rate increased slowly, and then decreased rapidly during the withering period along with the growth of R. pseudostellariae
Study of arbuscular mycorrhzizal fungi on decomposition of alfalfa litter
2009, 3(7): 40-43.
[Abstract](1408) [PDF 461KB](731)
Litterbag was used to study the effect of arbuscular mycorrhzizal fungus Glomus mosseae to the decomposition of alfalfa(Medicago sativa)litter. Litters were embeded in the soil and sampled at 4, 14, 21 and 28 days later. Results showed that dry weights of alfalfa litters gradually reduced over times. Inoculation with arbuscular mycorrhizal fungi remarkable improved the decomposition rate of alfalfa roots. Shoot and root N concentrations showed a rapid decline and then accumulated gradually. Shoot P concentrations increased initially and maintained a relatively stable level, root P concentrations maintained at a stable level generally. Root decomposition rate, N and P concentrations of alfafa with inoculating arbuscular mycorrhizal were remarkable higher than that of noninoculated control, but there was no significant difference in shoot.
The comprehensive evaluation of heat tolerance of 18 trifolium varieties
2009, 3(7): 44-49.
[Abstract](1751) [PDF 612KB](799)
The heat tolerance of 18 trefoil varieties were compared and evaluated comprehensively combined with germination and seedling field experiment. The results showed that the germination rate and the germination index declined with the temperature increasing. The seeds from all trefoil varieties could not germinate at the 40℃. The leaf firing rate, the survival rate of seedling and the leaf relative water content were different greatly in all varieties. The results of comprehensive appraisal indicated that the varietyTetri was the highest tolerant to heat, the variety New Zealand was higher tolerant, and the varieties Haifa,Huia,G18,Gollum,Retor,Badong,Pawera,Emu No 1 and so on were midtolerant to heat, Crau,Pitau,Aurora,Tetra were the varieties with lower tolerance to heat, while the tolerance to heat of variety Louisiana was the lowest. It was suggested that the varieties with higher heat tolerance should be planted in Yangtze River and its south region of China.
Observation of spike differentiation and flowering characteristics in Kentucky bluegrass
2009, 3(7): 50-55.
[Abstract](1554) [PDF 2096KB](763)
The spike differentiation and flowering characteristics in Kentucky bluegrass (Poa pratensis) were closely observed periodically throughout the development stages. The whole spike differentiation could be divided into 5 stages, which were the differentiation stage of first bract primordium, the differentiation stage of primary branch primordium, the differentiation stage of secondary and third branches primordial, the differentiation stage of spikelet and floret primordial, the stage of stamen and pistil primordial formation. The whole flowering progress in a spike of Kentucky bluegrass lasted about one week. The flowering order of the branches in the spike cob was from up to down, but the flowering order of florets in a single spikelet was from down to up, the flowering order of each branch was that the top flower blossomed first and then in bottomup order till the flower in the top of penultimate spike came into blossom. According to the relationships between spike differentiation stages and phenophase, the regulation practices for spike differentiation and yield formation in Kentucky bluegrass should focus on the specific phenophases.
2009, 3(7): 56-60.
[Abstract](1556) [PDF 924KB](1563)
This paper used CIRAS photosynthesis device which was made by British PP system company, to study the diurnal variation of photosynthesis for Medicago sativa in the area of Fukang under natural conditions. The results showed that 1)The variation curve of Medicago sativa showed twopeaks curve, and at 14:00, 15:00 of Beijing time, the photosynthesis for Medicago sativa exhibited an obvious midday depression phenomena. 2) The photosynthetic rate (Pn) sativa was 15.60 [mol/(m2s),CO2] daily averagely, with the highest value of 21.10 [mol/(m2s),CO2] at 12:00, and minimum of 1.16 [mol/(m2s),CO2] at 21:00. 3) The analysis of stepwise multiple regression and path coefficient showed that the photosynthetic active radiation (PAR), transpiration rate (Tr) and intercellular CO2 concentration were the main direct factors which affected the diurnal variation of Pn.
Study on photosynthesis and photoresponse characteristics of two types of Lespedeza hedysaroides
2009, 3(7): 61-65.
[Abstract](1295) [PDF 1424KB](697)
The paper studied the chlorophyll contents, photosynthesis and photoresponse characteristics of two different types of L. hedysaroides such as yellow green type and dark green type. The results showed that the chlorophyll contents of two types had significant differences. The maximum net photosynthetic rate(Amax), dark respiration rate(Rd) and apparent quantum yield(AQY) of dark green type of L. hedysaroides were higher than the yellow green type, and the apparent light compensation point(LCP) and light saturation point(LSP) of dark green type were lower than that of the yellow green type. The light radiation net photosynthetic rate(Pn), interceller CO2 concentration(Ci), stomatal conductance(Gs), transpiration rate(Tr), water use efficiency(WUE) and leaf temperature of the two types showed different responses to the photosynthetic available radiation flux density(PPFD) to some extent.
The modular characteristic of the annual psammophilous Bassia dasyphylla
2009, 3(7): 66-71.
[Abstract](1462) [PDF 1162KB](790)
The experiment was conducted on the morphological and biomass spatial distribution characters of the annual psammophilous Bassia dasyphylla in Minshazui of Gulang County in Gansu. The results showed that the crown, ground diameter, root depth, root range, lateral root number and length all had very significant linear positive correlations with plant height(P<0.01) , the degree of correlations between aboveground morphological index and height was higher than the underground. The tress had more ramification, the number of first order ramification was 30.40, the secondary ramification reached 260.87. The average single biomass of B. dasyphylla was 74.21 g, the aboveground part was 67.83 g, and the underground part was 7.38 g.The aboveground biomass concentrated in 1030 cm, this layer occupied 77.64% of aboveground part, the components according with the size of biomass in order as tress, fruit, leaf. The underground part biomass concentrated in 010 cm, this layer occupied 76.29% of underground part, and lateral root was more developed than main root. Differences of fresh and dry biomass of components in different layers were basically similar, the differences of 1020 cm and 2030 cm compared with 3040 cm and 4050 cm of aboveground were significant, the differences of 010 cm compared with 1020 cm and 2030 cm of underground were significant, however, there was no significant difference in other different layers.
Production performance comparison of four Alfalfa varieties in oasis region of North Xinjiang
2009, 3(7): 72-76.
[Abstract](1492) [PDF 562KB](705)
The experiment was conducted in order to compare the production performance of four alfalfa (Medicago sativa) varieties in oasis region in four continuous years from 2004 to 2007.The result showed that the average growth rate (AGR) of WL-323 was faster than Algonquin, their AGR showed the character as slowquickslow, Pandus and Golden Queen had the greatest AGR in three years; and in the third year, AGR of Pandus was the quickest in all varieties. Total forage yield for all the varieties during the four years had significant difference(P<0.01),which ranked as PandusGoldeQueenAlgonquinWL-323. The forage yield decreased rapidly in the fourth year; Pandus had the highest crude protein content. The comprehensive evaluation showed that Pandus had best performance in all varieties, and could be preferably considered in introduction in oasis region.
Effects of salt stress on seed germination and emergence of different oats varieties
2009, 3(7): 77-81.
[Abstract](1770) [PDF 495KB](695)
Culture and field experiments were individually used to study the effect of 50250 mmol/L NaCl stress on the seed germination and the condition of emergence and seedling growth for oats varieties, in order to supply the theoretic basic for the evaluation and selection of salt tolerance in oat germplasm resources. The results indicated that the germination percentage, germination index and vigor index decreased greatly with the increase of salt concentration under 50250 mmol/L NaCl stress, in which the vigor index was most sensitive to salt stress. The germination percentage, germination index and vigor index of M2002 and Baiyan No.6 decreased more slowly with the increase of salt concentration compared with the V2006 and Neisan No.2. NaCl stress inhibited both the growth of roots and sprouts during the germination stage of oats, and the inhibition effect to roots was greater than that to sprouts. The root amount of oat was promoted under 50100 mmol/L NaCl concentration, but it was decreased when NaCl concentration over 150 mmol/L. The emergence percentage and dry matter amount in 4 oats varieties seedling had significant difference, in which the emergence percentage and dry matter amount of M2002 and Baiyan 6 significantly higher than the V2006 and Neisan 2.
Path coefficient analysis between seed yield components and seed yield of Setaria sphacelata cv. Narok
2009, 3(7): 82-87.
[Abstract](1526) [PDF 556KB](668)
This paper used multifactor split plot designed field experiment, through the correlation analysis, path coefficient analysis and stepwise regression analysis for seed yield components and seed yield. The result showed that the order of six seed yield components of Setaria sphacelata contributing to seed yield was florets/cm, 1 000 seeds weight, inflorescence length, fertile tillers/m2, spikelet numbers /cm and seed numbers/cm in sequence. So improving the florets/cm, 1 000 seeds weight and inflorescence length was the most effective way to increase seed yield. The next was to increase spikelet numbers/cm, florets/cm and fertile tillers/m2.
Study on the germination conditions of Bromus cartharticus
2009, 3(7): 88-93.
[Abstract](1336) [PDF 1490KB](691)
The influences of different temperatures, germinating beds and lights on the germination characteristics of Bromus cartharticus were discussed in germination test. The conditions of temperatures included seven constant temperatures (10、15, 20, 25, 30, 35 and 40 ℃) and two alternating temperatures (15/25 ℃ and 20/30 ℃), light treatments included darkness (0 lx) and 2 000 lx light intensity, and bed treatments were carried on the top of paper(TP), between of paper(BP), top of sand(TS) and between of sand(BS). The optimum seed germination temperature of B.cartharticus was 25~30 ℃, TP was the best bed and light insensitive.
Comprehensive evaluation of nutrient value for the winter and spring supplement feeding forages in the alpine pastoral area of Northwestern Sichuan
2009, 3(7): 94-98.
[Abstract](1824) [PDF 560KB](849)
Through the entropy weight based entropy way, the gray related degree method was used to evaluate nutrient value of 6 supplement feeding forages synthetically. Results showed that the silage forage of Avena sativa variety Y61005 presented the highest nutrient value, which had the highest content of crude protein (CP), crude fat (EE), crude ash(ASH), calcium (Ca), and the least content of crude fiber(CF) and neutral detergent fiber (NDF). The withering grass of natural grassland and the straw of Elymus sibiricuson variety Chuancao NO.2 after seed harvested had lower nutrient value. In generally, the nutrient value of A.sativa forage was better than the E. Sibiricuson, and the silage forage was better than the hay. The A. sativa planting and ensiling technologies should be popularized in order to improve stockbreeding productivity in alpine pasture.
Effects of reseeding alpine No#1ecograss on degraded alpine meadows in Maqu after enclosure
2009, 3(7): 99-104.
[Abstract](1524) [PDF 1457KB](730)
In order to study the improvement effects of enclosure and reseeding on degraded alpine meadows (subalpine meadows and swamp meadows), the tests of enclosure and reseeding alpine No#1 ecological mixture grass in degraded alpine meadows of the eastern QinghaiTibetan Plateau was conducted. The mean vegetation height and coverage, aboveground productivity of enclosure and reseeding were monitored after three years. Results showed that enclosure significantly increased the average vegetation height (49.57% and 53.38%), coverage (24.73% and 25.25%) and aboveground productivity (16.40% and 22.17%) in degraded subalpine meadows and swamp meadows, but there was no significant difference for species richness compared with the control. Reseeding alpine No#1 ecological mixture grass in fenced meadows had better effects, which could also significantly increased the mean vegetation height (17.64% and 15.78%), coverage (48.38% and 50.50%) and aboveground productivity (3.24% and 9.39%) in these twotype degraded meadows, respectively; an increase in species richness was observed. In conclusion, enclosure and reseeding were all effective improving measures for degraded alpine meadows, and their cooperation would be better than enclosure only. Additionally, the alpine No#1 ecological mixture grass showed favorable adaptability and effect on reseeding and improving degraded alpine meadows.
The study on dry farming technology of the plant density for Hedisarumu scoparium on the desert pasture of Hexi Corridor
2009, 3(7): 105-109.
[Abstract](1448) [PDF 570KB](699)
200 hectares of transplanted Hedysarum scoparium were established with various density (2 m2 m, 2 m3 m, 3 m3 m and 3 m4 m) in the desert pasture of Gaotai County in Gansu during the year of 2004. The plots were set for 4years continuous observation of the change conditions on survival rate, ramification number, height, canopy size and biomass. The result showed that 3 m3 m and 3 m4 m were the best density and under these densities, H. scoparium grew vigorously, ramified densely and developed good roots, plant species between the clumps of H. scoparium increased, and the coverage enlarged with an obvious sandfixation effect. The density greater than 3 m3 m and 3 m4 m resulted in H. scoparium dwarfed and developed slowly; the original species between the clumps of H. scoparium disappeared with a poor sandfixation effect.
Study on the determination of the nutritional components and the feeding value of Broussonetia papyrifera leaf meal
2009, 3(7): 110-114.
[Abstract](1924) [PDF 548KB](832)
The crude protein, crude fiber, calcium and phosphorus and 17 amino acids in the leaf meal of Broussonetia papyrifera were measured. The protein nutritional value was expressed as essential amino acid score and index. The feeding value was evaluated by the fuzzy optimum decision method. The results showed that B. papyrifera leaf meal was a protein feed which contains 23.62% crude protein and 20.95% seventeen amino acids. The ratio of E/T and E/N were 0.44 and 0.80, which were higher than the reference of 0.40 and 0.6 provided by FAO / WHO, respectively. Amino acid score of B. papyrifera was 50, which was lower than the leaf meal of tetraploid black locust, powder of pine needle and alfalfa meal. The essential amino acid index of B. papyrifera was 95.24, which was equal to that of above control feeds. The fuzzy optimum decision analysis showed that the leaf meal of B. papyrifera has a greater feeding value than alfalfa meal and the powder of pine needle, but its value was lower than tetraploid black locust meal.
Interaction between arbuscular mycorrhizal fungi and plant intraspecific competition
2009, 3(7): 115-121.
[Abstract](1717) [PDF 632KB](731)
Arbuscular mycorrhizal (AM) fungi and intraspecific competition are considered as the two main factors which affect plant populations structures and stabilities. By the intermediator of plants, the interaction between AM fungi and plant intraspecific competition has become one of the hotspots in ecology, which study on revealing plant growth, reproduction and the stability of plant population. On the basis of this, this study focus on the effects of AM fungi on individual plant in the same ages populations and the different ages populations, such as AM colonization, AM fungi spores density, and biomass of hostplant etc. Otherwise, the feedback of intraspecific competition on AM were also discussed.
Study on the antifungal activityof endophyticfungi from Kobresia capillifolia
2009, 3(7): 122-126.
[Abstract](2555) [PDF 690KB](733)
Seven endophytic fungi were isolated from Kobresia capillifolia (Decne.), three of them belong to Fusarium sp., one belongs to Acremonium sp., one belongs to Periconia sp., and the remaining two strains didnt bear spores, and can not be identified by morphological methods. The seven strains were measured of their colony growth rate. Moreover, their antifungal activities to 4 different plant pathogens including Rhizoctonia solani(R1), Bipolaris sorokiniana (B1), Pythium ultimum (P1)and Fusarium oxysporium (F1) were tested. The results showed that 71.43% of the strains have good characteristics of living in lowtemperature environment; Four of them had strong inhibition on B. sorokiniana, the strain SY3 had the strongest inhibition on B. sorokiniana, its inhibitory rate was over 61.84% and it's inhibition area was beyond 10 mm; Four of them had weak inhibition on R. solani, their inhibitory rate were low, and inhibition areas were not obvious; The inhibition on F. oxysporium was pretty week, inhibition areas were not obvious; Only one strain had strong inhibition on P. ultimum, whose inhibitory rate was 13.75%, and the inhibition area was 5 to 10 mm.
2009, 3(7): 127-132.
[Abstract](1542) [PDF 598KB](1502)
This study explored the effect of different densities of Brandts voles (Lasiopodomys brandtii) nibbling on plant community structure and the root biomass under simulated conditions. The results showed that: 1) the effect of low density voles on the vegetation community structure was not significant, but high density voles could change grassland vegetation community structure. The vegetation community degradation succession appeared at density of 5 voles in each 100 m2,showing the reduction in the proportion of highquality forage and increase in the proportion of other weeds, grassland tended to degrade. 2) Nibbling Brandts voles promoted the stems and leaves withering and accelerated the vegetation succession. There was positive correlation between the withering rate and densities of Brandts voles. 3)Relationship between the vegetation root biomass and voles density appeared the highlowhigh trend, and the root biomass was the lowest at the density of 8 voles in each 100 m2. The fibrous root plants were decreased and the axial root plants such as weeds were increased.
Yield loss and identification of variety resistance to black bundle of maize
2009, 3(7): 133-136.
[Abstract](1289) [PDF 496KB](720)
The resistant and susceptible varieties of maize to Acrimonium strictum had different yield. Infected plants could not form female ears or decreases of grain number per ear and 1 000grainweight. The average yield loss was up to 66.0%. The yield loss for disease tolerant variety was mainly caused by the decrease of grain number per ear, and the average yield loss was 14.7%. Soil inoculation test was applied to 1 382 maize accessions in 2005 and 2006. It was showed that 1 097 accessions or 79.3% were not infected, 5 were highly resistant and another 5 were resistant accessions, each accounting for 0.36%; 15 accessions were disease tolerant and accounting for 1.08%; 27 (2.0%) were sensitive accessions; 233 accessions or 16.9% were highly sensitive. Meanwhile, preliminary study was conducted on the relationships between the content of stem reductive sugar, total phosphorus, total nitrogen, coarse protein and disease resistance of varieties.
Impacts of the invasion of Alternanthera philoxeroides on the species composition and diversity of native vegetation community
2009, 3(7): 137-142.
[Abstract](1698) [PDF 1512KB](762)
The influence of invasive Alternanthera philoxeroides on local vegetation community composition and biodiversity was systematically studied in the suburb of Shangrao city, Jiangxi province. 20 plots which were invaded by A. philoxeroides, were established. One plot which was none or a few A. philoxeroides individuals selected as control plot with a distance of 5 m from others. The pattern of local community biodiversity was analyzed by Simpson index, ShannonWiener index,Pielou index, and Alatalo index. The results showed that: 1) There were totally 59 species in all plots which were subordinated to 29 families. The numbers of species in tested plots were lower than those in the control; 2) There were significant differences of the importance value distribution between the tested and control plots, indicating that the patterns of the species in the local vegetation community changed under the invasion of A. philoxeroides; 3) Analysis of relationship between importance value and biodiversity indices of the local community revealed that Simpson index, Shannonwiener index, Pielou index and Alatalo index were all increased before the importance value of A. philoxeroides reached 29.7, then reduced when the importance value was higher than 64.3, all the indices decreased sharply. This indicated that the invasion of A. philoxeroides had the positive effect and negative effect on the local vegetation community biodiversity. The local community biodiversity could reduce when the invasion of A. philoxeroides reached a threshold.
Fractal dimension characteristic of soil particles during the grassland reclamation and protection
2009, 3(7): 143-146.
[Abstract](1324) [PDF 637KB](812)
In order to enhance the quantificational characteristic on the recovery condition of deteriorated grassland, the variability of soil physicochemical property and its relationships with fractal dimension of soil particle were studied in native grassland and artificial irrigation pasture in Maowusu desert. It was showed that the values of fractal dimension was 2.35 to 2.54, the contents of sand and the fractal dimension in artificial irrigation pasture were larger than those in native grassland, and the contents of organic matter was less than the native grassland. The conclusions considered that the relationships of the fractal dimension with the contents of clay and organic mater were positive correlation, the relationship with the contents of sand was negative correlation. It meant that the variability of soil physicochemical property could be indicated by the fractal dimension of soil particle, which was an aggregative and quantificational index in evaluating the soil degeneration degree of desertification grassland.
Study on asexual propagation of the wild leguminous plant of Desmodium tiflourum
2009, 3(7): 147-151.
[Abstract](1404) [PDF 0KB](475)
Rapid reproduction technique of nutritive part of Desmodium tiflourum in subtropical climate of Guangdong was studied. The results showed that D. tiflourum was adapted to various soil conditions, and its average planting survival rate in various soil was over 83%, with 96% in latosol. The D. tiflourum could be planted in spring, summer and autumn, and the survival rate reached 98% in July. The survival rate of various asexual propagation methods was more than 92%, and the highest rate was 98%. Plant moisture retention and avoiding wilting was the key of promoting the survival rate. The superior soil substance used for asexual propagation or turfestablishment was latosol, and the optimum season was summer.
Effect of water and fertilizer coupling on ecological characters of Festuca arundinaceaunder heat stress
2009, 3(7): 152-157.
[Abstract](2059) [PDF 0KB](398)
This paper designed the low, middle and high water levels and three levels of nutrients with pot test under controlled conditions, studied the impact of different methods of water and fertilizer coupling on the ecological characters of tall fescue (Festuca arundinecea cv.Barlexas) under hightemperature (38/30 ℃, day / night) stress. The results showed that water and nutrients and the coupling effect had a remarkable impact on the ecological characters of tall fescue, the method of coupling water and fertilizer was better than single irrigation. The best way of coupling water and fertilizer was medium water and fertilizer (f2w2), it maximized to improve the ecological characters of the tall fescue, and prolonged the green period under heat stress, but inadequate water and basin irrigation or insufficient or too much nutrients were not benefit to the growth of tall fescue, and the moisture had greater effect on tall fescue than fertilizer under heat stress.
Study on the conservation management techniques of Sedum lineare at the roof greening of Beijing city
2009, 3(7): 158-164.
[Abstract](1502) [PDF 0KB](545)
The trial goal was to define the conservation standard of Sedum lineare in roof greening. The annual water requirement and irrigation time were determined, the plant growth and diseases and insect pests occurrence were investigated, the pruning time and weeds control method were determined. The results showed that the moisture content of roof greening substrate and plant water content of S. lineare were not correlated. When the substrate was 6 cm and plant height was 8 cm to 12 cm, the annual adaptive watering amount was 361.45 mm. If the substrate was 10 cm and plant height was 25 cm to 30 cm, the annual watering amount was 533.90 mm. There was usually physiological disease on S. lineare induced by the alternation of the water log and excessive drought. The main insect pests were aphid and snail of S. lineare, but no serious damage was observed. Moderate pruning could prolong the green period of S. lineare in autumn. The optimum pruning length was 1/3 to 1/2 of the plant height. Weeds control was an important measure for the conservation of S. lineare. The artificial irrigation was necessary for the conservation management of S. lineare, such as regeneration watering, dry and hot season and winter irrigation.
Discussion on usage of shrub and herbaceous plant in river slope regulation project
2009, 3(7): 165-172.
[Abstract](1352) [PDF 0KB](396)
The river slope environment was deteriorated by the ruin of the river slope. Using biologic ways could improve the water and soil conservation capacity of the slop, especially through planting shrub and herbaceous plants. The developed roots of plants effectively enhanced the stability of the slope through anchoring and reinforcement effect. Planting could restore the ecological functions of the slope and increase their erosion resistance ability in the relatively short period of time. Shrubs and herbs were the main plants for slope protection, and plants with the developed roots and strong resistance were usually used at present. Different soil, climatic conditions and different geographical areas were suitable for different shrub and herbaceous plant to grow, so local environmental conditions must be considered when choosing suitable plants for slope protection. If not, it would be very difficult to succeed. This paper expatiated ecology effect and slope protection mechanism of plant. It also summarized staple shrub and herbaceous plants used for river slope regulation project. Lastly, it cited a number of vegetation could be used to protect slope in northern China, and expected to make suggestions for the selection of shrub and herbaceous plants in slope protection project.
The study of the method for isolation and purification of ct DNA from turfgrasses
2009, 3(7): 173-176.
[Abstract](1865) [PDF 0KB](387)
Four turfgrass including Festuca elata, Lotium perenne, Cynodon dactylon and Zoysia sinica were selected as the materials, the chloroplast was isolated by improved differential centrifugation, and the ctDNA was extracted with the CTAB and tested by Agarose gel electrophoresis. The results showed that the purity of ctDNA was high, the bands were clear, the ratio of intact chloroplast was high with the improved CTAB method.Compared with traditional method of ctDNA isolation and purification, CTAB method eliminated the steps of consuming material and time in traditional density gradient centrifugation; it was simple, rapid and high yield. So the improved CTAB method provided a reference for the extraction of Gramineae plants ctDNA, which was applicable for biological experimental teaching and research activities.
Effects mowing height of seashore paspalum on Kyllinga brervifolia control with CaoPingNing 71#
2009, 3(7): 177-180.
[Abstract](1627) [PDF 0KB](502)
The study was conducted to determine the effects of mowing height on Kyllinga brervifolia control with CaoPingNing 71# and leaf color, growth vigor of seashore paspalum (Paspalum vaginatum) in Dongguan Hill View Golf Club during 2007 and 2008. The results showed that applied Caopingning 71# at 1 kg/hm2 to control K. brervifolia at the mowing height of 10 mm, 15 mm, 20 mm, 25 mm,30 mm and 35 mm at 5-7 leave stage, the control effectiveness was 93.9%, 83.4%, 80.8%, 74.1%, 58.3% and 39.7% respectively, after 14 days. 28 days after the control effectiveness was 100%, 99.5%, 96.8%, 94.2%, 80.7% and 75.5%, respectively. K.brervifolia fresh weight control effectiveness was 100%, 99.7%, 98.1%, 94.1%, 91.6% and 90.6%. The effectiveness was improved with the decreasing mowing height of seashore paspalum, and the best mowing height was below 25 mm. There was no bad effect of 1 kg/hm2 Caopingning 71# applied to different mowing height of seashore paspalum on leaf color and growth vigor. The trial demonstrated in Citic Shantou Golf Club in 2008. It was further proved that effectiveness of K. brervifolia control with CaoPingNing 71# were more than 85% in the mowing height below 25 mm for seashore paspalum.
Research of Turfgrass in City Garden
2009, 3(7): 181-185.
[Abstract](1475) [PDF 0KB](362)
On the basis of several years' research, 219 turfgrass cultivars belonging to 17 species and 11 genera were introduced and collected. Through systematical observation and evaluation, 27 superior cultivars with good adaptability to the soil and climate of Tianjin were selected, including cold season turfgrasstall fescue, warm season turfgrassbuffalograss and Zoysia japonica. The resource pool of turfgrass including over 200 cultivars were set up. During the research of seed propagation technology of tall fescue, its growth rule in Tianjin was grasped; the best sowing rate, appropriate sowing period and the best harvesting time were determined, which established the good base for the lawn research in Tianjin.
Causes and countermeasures of degradation and desertification of natural meadow in Haibei District of Qinghai Province
2009, 3(7): 186-190.
[Abstract](1480) [PDF 0KB](411)
e natural meadow resources were abundant in Haibei district, but the desertification and degeneration became serious gradually with the continuous stockbreeding development for many years. According to the fact of natural meadow deterioration and desertification in Haibei district, this paper analyzed the harm of meadow deterioration and desertification, expatiated emphatically the multilayers causes, and put forward corresponding countermeasure and suggestions. The result showed that the direct causes of meadow deterioration and desertification in Haibei were overloading, overgrazing and the break of biological chain; the indirect causes were population increment and livestock technical application, the fundamental causes were frangibility of meadow ecosystem environment induced by alpinecold climate characteristic and complicated geography. Finally, three strategies were put forward, including encouraging family planning, increasing education investment, controlling and reducing the husbandry population, implementing modern and efficient stockbreeding development mode, developing artificial grassland, determining domestic animal number according to forge production, building the protection consciousness, and developing finite governance of natural meadow.