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The influence of grazing intensity including light grazing, moderate grazing and heavy grazing on soil organic matter, soil available nitrogen, soil available phosphorus and soil available potassium in Zhaosu meadow steppe by plot grazing experiment under short grazing period was studied. Results showed that the aboveground biomass of grassland declined along with the increasing of grazing intensity, and there were no significant difference among different grazing intensities (P0.05). The content of soil organic matter, available nitrogen, available phosphorus and available potassium of 0-10, 10-20, 20-30 cm were not significantly different among different grazing intensities at the same year (P0.05). Compared with no grazing, soil nutrition content of 0-30cm appeared a trend of increasing or decreasing in a certain degree after grazing. And,different indexes had different change trend, which embodied annual changes. Correlation analysis suggested that there was no significant correlation between grazing intensities on soil organic matter, soil available nitrogen, soil available phosphorus, and soil available potassium of 0-30 cm (P0.05). Response of these soil nutrition to grazing intensities was different. Whether grazing or not, the content of soil organic matter, soil available nitrogen, soil available phosphorus, soil available potassium all decreased with the increasing of soil depth.
Taking Amorpha fruticosa with different cultivation ages in Southern Mu Us desert as objectives, a study was made on the physical composition and nutrient content of soil under A.fruticosa, and correlation between soil nutrients and dust particles were analyzed. The results showed that refined degree of soil under A. fruticosa increased gradually with the increasing of A. fruticosa cultivation ages. For example, the refined degree of surface soil (0-10 cm) was 1951197619832005, and dust particles content of A. fruticosa planted in 1951 was 4.3%. pH values of vertical soil profile in A.fruticosa decreased from bottom, and pH value of surface soil (0-10 cm) was the lowest. pH values of the same soil layer reduced with the increasing of cultivation ages. All nutrients content (except of total K and NH4+N) of soil (0-20 cm) increased in varying degrees. The content of organic carbon, total N, NO3-N, total P and rapid available P increased with the increasing of cultivation ages, while there was no apparent regularity in content of NH4+N and total K.
The soil samples were collected in different vegetation types and different altitude gradients at depths of 0-20 cm and 20-40 cm in Gaoligongshan. The amount distribution of soil microbial groups with different vegetation types and different altitude were studied by using the microbial incubation methods. The results showed that with the increase of altitude gradients, most of soil microbial groups showed a single peak trend in their quantities, ie, lowhighlow. The quantity of soil microbial groups was in the order, ammonifying bacteriabacillusdenitrifying bacterialaerobe azotobactenitrifiersazotobacterphosphorus solubilizing bacteriaaerobe cellulose decomposing bacteriaoligotrophic cellulose decomposing bacteria. Total numbers of soil microbial groups in different vegetation types was in the order, broadleaf forestmixed woodshrub forestcoffee landsnowfield.
The research was made, using tall fescue (Festuca arundinacea) and Kentucky bluegrass (Poa pratensis) as experimental materials, on the changes of number of tillers, turf quality, turf color, ground biomass, soil compaction and troots distribution after different traffic stress treatments on them. It showed that light traffic could improve the number of tillers, turf quality, turf color and ground biomass, then improve the use value of turf. With the inereasing of traffic intensity, soil compaction of flat bed increased and 0-5 cm root distribution of Kentucky bluegrass and 10-15 cm root distribution of tall fescue were also changed .
A pot experiment was conducted to determine the effects of different concentrations of four kinds of growth regulators on plant height, length and width of leaf, tillers, dry weight and fresh weight of perennial ryegrass (Lolium perenne). The results showed that the different concentration of four plant growth regulators were significantly inhibited the growth of plants. 200 mgL-1 of Paclobutrazol and 375 mgL-1 of Aibis treatments were suggested for chemical pruning of perennial ryegrass.
Based on GIS spatial analysis, the NDVI timeseries data of different vegetation types in northeast China were extracted by using the NDVI data from 1998 to 2008. Meanwhile, the phenological phases of vegetation types were simulated by Logistic function with their variation trends in 1998-2008. Results showed that 1) in 10 years, the date of vegetation beginning to grow was stable in Songnen Plain, and the growth trend in the local area was earlier than normal with a more than tendays value; 2) in the study area, the vegetation final date delayed evidently with a threeday average scale; 3) in a word, the change trend of vegetation grown season in Songnen Plain fluctuates between 2 and 3 days.
Kobresia has poor germination condition under natural environment. Potassium nitrate solution, sulphuric acid, sodium hydroxide solution and warm water were used to treat five species of Kobresia (K.setchwanensis, K.royleana, K.littledalei, K.capillifolia and K.pygmaea) seeds from different altitudes in this study. The results revealed that differences among cultivars and four treatments have significant impacts on germination potential, germination rate, shoot length and root length, and the effect of various cultivars on germination potential and germination rate was great. The best method of increasing shoot length for K.setchwanensis and K.littledalei is to immerse seeds in 40% sodium hydroxide solution. Under this treatiment the germination rate of those twoo grass are 98.00% and 73.33% respectively, and the latter reached a significant level compared with controlled trails. All the five cultivars of Kobresia shoot length reach highest with treatments of sodium hydroxide solution, which are more than 13.00 mm. Potassium nitrate solution, sulphuric acid and warm water also have implications for five cultivars of Kobresia.
Effects of different soil water stress degrees on physiological characteristics of Misconstrues sacchariflorus were studied by four treatments: CK (keep the maximum capacity of 80%, the same below), light water stress (65%), moderate water stress (45%), and severe water stress (30%). Results showed that the leaf relative water content (RWC), specific leaf weight (SLW) and chlorophyll (Chl) content, maximum net photosynthetic rate (Pmax), apparent quantum efficiency (AQE), dark respiration rate (Rd), transpiration rate (Tr), intercellular CO2 concentration (Ci), stomatal conductance (Gs), light saturation point (LSP) and light compensation point (LCP) decreased with the increasing of the degree of water stress (P＜0.05). However, stomatal limitation (Ls) showed a rising trend(P＜0.05), while water use efficiency (WUE) increased firstly and then decreased(P＜0.05). Leaf gas exchange parameters and physiological indicators of M.sacchariflorus showed poor adaptive capacity to water stress with low plasticity.
The photosynthetic properties of three chicory (Cichorium intybus) lines were investigated under water stress through pot experiment. The lines which included spacemutagenesisbred lines(PA82 and PA43),and their initial strain (Puna chicory) were studied using Li6400 portable photosynthesis system. The results showed that, diurnal net photosynthetic rate (Pn), transpiration rate (Tr), and stomatal conductance (Cond) presented as doublepeak curves. There was an obvious midday Pn depression, which was caused by nonstomatal factors. The highest Pn, Tr and Cond values were observed in PA82, and the lowest corresponding values were observed in PA43 (P0.05). Intercellular CO2 concentration (Ci) of three lines showed an opposite course to that of Pn, which reached its valley at 10:0012:00. PA82 had the highest water use efficiency (WUE), followed by Puna chicory, then PA43. Both of them indicated a good adaptation to changes of light intensity. Pn, Tr, Cond, maximal photochemical efficiency of PS II in dark adaptation (Fv/Fm), potential photochemical efficiency (Fv/F0), and coefficient of photochemical quenching (qP) decreased with the aggravation of water deficit. Among the three lines, the parameters of PA43 dropped to a greater extent at the highest speed, followed by Puna chicory, then PA82. With the aggravation of water deficit, Ci and coefficient of nonphotochemical quenching (qN) increased to a greater extent at the highest speed in PA43. The results suggest that PA82 and Puna chicory have higher resistance against severe water deficit in comparison with PA43.
The database of the name and the palatability level of each wild feeding plants from available literatures, field investigation, farmer interviews and expert advices in Weining County, Guizhou Province were built. The herbaceous and woody life forms and their feeding values were analyzed. The differences of feeding organ and palatability level of each species in this area, and the wild feed plants were divided into excellent, good, medium and bad levels. The results indicated that the wild feeing plants included 55 families, 77 generas and 384 species, in Weining County, mainly from Gramineae, Leguminosae, Asteraceae, Rosaceae, Cyperaceae and other 10 families. Herbaceous and woody species respectively accounted for 76% and 24% of the total plants, and the woody/vine plants mainly distributed in Leguminosae (26 species) and Rosaceae (23 species). The feeding values of most of species of Gramineae, Leguminosae and Cyperaceae were high. Grazing animal behavior, feeding rate and ration composition of cattle, sheep and goats were different. It was pointed out that the forage shrubs with higher biological active substance could be used as the supplementary feed components or biological health care medicine additives, the mixed grazing of different livestock should be putted into grassland management practice in Weining karst area, the wild forage of medium feeding of this area could be used as the supplementary feed in winter and the utilization of natural and artificial grasslands was equivalent.
Ripening effects of three types of ripeners, including glyphosate, ethylene and glyphosateethyphon mixed preparation on Miscanthus plant was studied taken Miscanthus floridulus 02142 and hybrid combination Xiangzamang No.2 as materials. The results showed that all three types of ripeners had significant effects on decreasing SPAD value of leaves, and effects of glyphosate and glyphosateethyphon mixed preparation was equal, while that of ethyphon was weaker. Significant effects of three types of ripener on promoting dehydration of Miscanthus plant was observed, effects of glyphosateethyphon mixed preparation was strongest, and effects of ethylene was weakest while it had significant enhancement effects on glyphosate. As to contents of N, P and K in Miscanthus plant, ethyphon showed increasing effects commonly, while glyphosate and glyphosate ethyphon mixed preparation showed significant decreasing effect, and effects of treatment of glyphosate 10 mLL-1+ ethyphon 2 mLL-1 was the strongest. In a word, ripening effect of glyphosateethyphon mixed preparation was the strongest, and the optimal concentration was glyphosate 10 mLL-1+ ethyphon 2 mLL-1.
In order to investigate the feasibility of leguminous shrub and grass species applied in coniferous artificial forests renovation and silvopastoral vegetation construction, allelopathic effects of different concentrations (10, 20 and 40 mgmL-1) of water extracts from decomposed leaf litters of P.tabulaeformis, P.orientalis, L.principisrupprechtii and P.sylvestris on seed germination and seedling growth of A.fruticosa, V.villosa and M.officinalis were studied. The results indicated that 1) P.tabulaeformis litter extracts inhibited the seed germination of V.villosa and M.officinalis, and showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa and seedling growth of V.villosa; 2) P.orientalis litter extracts decreased the germination rate of V.villosa, and promoted seed germination of M.officinalis and the growth of V. villosa seedling and A.fruticosa radicals, and showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa and the growth of A.fruticosa seedling and M.officinalis seedling; 3) L.principisrupprechtii litter extracts inhibited the seed germination of A.fruticosa and V.villosa, promoted the seed germination of M. officinalis and the growth of V.villosa seedling and M.officinalis radicals, and showed the law of lowerstimulation and highinhibition on the seedling growth of A.fruticosa; 4) P.sylvestris litter extracts showed the law of lowerstimulation and highinhibition on the seed germination of A.fruticosa, inhibited seed germination of V.villosa and M.officinalis and the seedling growth of A.fruticosa, while they could promote the growth of V.villosa seedling and A.fruticosa radicals, lower concentration extract promoted the seedling growth of M.officinalis significantly; 5) Analysis results of three leguminous shrub and grass seedlings MDA content and their seedling growth analysis results were consistent. MDA content might be the most sensitive indicator to measure the allelopathic effect.
A field survey in Maqu and Tianzhu Counties was conducted to determine the features and plant diversity of alpine meadow communities in northeast and east edge regions of QinghaiTibetan Plateau by calculating and diversity index and measuring community structure and aboveground biomass. Results showed that the dominant plants in the northeast and east regions were Korea capillifolia The community height and corerage in the east region were bigger than those of northeast regions. The vertical structure of alpine meadow was double layers in east and northeast regions. The richness index of alpine meadow communities and significantly difference between northeast region and east region，and evenness index of alpine meadow communities in east region was significantly bigger than that in the northeast region (P0.05). The diversity index of alpine meadow communities in east region was bigger than that in northeast regions. The diversity index of alpine meadow communities in east region was significantly bigger than that in northeast region (P0.05). The aboveground biomass of alpine meadow communities in east region was bigger than that in northeast region. This study indicated that the alpine meadow at the different regions showed an obvious differentiation in community features，plant diversity and primary productivity. It was suggested that grassland management measurements should be tailored by local requirement to maintain stable productivity and conserve the biodiversity of alpine meadow in QinghaiTibetan Plateau.
A study of four major grassland types (alpine meadow, alpine steppe, temperate steppe and alpine swamp meadow) in central Tibetan Plateau was carried out in 2004. And the seasonal variations of abovegraund biomass (AGB) and growth characteristics were analyzed. Results showed that the highest AGB occurred in fenced swamp meadow with annual mean AGB of 384.45 gm-2, which was 6 times of temperate steppe and 12~14 times of alpine steppe and alpine meadow, and it was also obviously higher than unfenced alpine swamp meadow with 73%. Compared with free choice grazing, enclosure obviously increased AGB and was one of the most effective approaches to improve degraded grassland. The production of temperate steppe was higher than alpine meadow and alpine steppe, and the grassland AGB near urban areas was greater than areas away from urban region, and urbanization was an effective way to reduce the intensity of grassland use and to restore grassland productivity. As semiarid temperate climate zone, soil moisture was the main factor to constrain grassland vegetation growth in Tibet. Absolute growth rate (AGR) and relative growth rate (RGR) of four grassland types were positive before reaching to apex of the vegetation growth and negative after apex. Due to differences in hydrothermal conditions and their seasonal variations results in different fastest growing period of AGB for four grassland types.
A study on the community structure and productivity, and plant composition and diversity of alpine meadow under different degrees of degradation, including nondegradation, lightdegradation, moderatedegradation, heavydegradation and overdegradation in the upper area of Daitong river. Results indicated that there were more than 60 plant species, which are belong to 24 families and 51 genus, in study ared. The dominant species in was conduced nondegradation and overdegradation grasslands were Kobresia pygmaea and Saussurea pulchra, respectively. The ShannonWiener index and Simpson index in moderatedegradation (P0.05) were the highest. With the increasing of degradation, the biomass of weeds increased(P0.05), and the vegetation coverage, biomass of high quality forages, total aboveground biomass and grassland quality decreased.
In order to cultivate a new cultivar with resistance, high yield, and excellent nutritional quality, and get excellent plant resources, feeding traits of high protein new germplasm of Elymus nutans had been observed for two continuous years. The seasonal dynamics of protein content and characteristics of amino acid components have been studied. The results showed that feeding quality of QE36 performed steadly, and nutritional quality traits (high protein, low fiber) were significantly superior than that of control (GE07). In the whole growth period, the content of crude protein reduced, and the crude protein content of QE36 was higher than that of GE07, and had significant differences from heading stage to booting stage. In early flowering, the content of amino acid composition in material QE36 was significantly higher than that of GE07, and the essential amino acid content was 1.6 times of GE07. In conclusion, QE36 could be served as an excellent high protein Elymus nutans germplasm materials.
Leaves of introduced, wild and domesticated cultivation vetiver population were analysed with large sampling. The results showed that there were differences in tiller height, leaf biomass and percentage of leaf biomass among four populations. There were also differences in leaf development and growth processes including leaf length, and ratio of leaf width to length. But the same power function explained the relationships between different leaf characteristics. These results indicate that leaves of four populations have the same convergent biomass growth pattern and convergent leaf growth processes.
The purpose of this study was to evaluate and improve immune performance of Liaoning cashmere by sifting the optimum level of dietary manganese. 60 healthy 2.5yearold Liaoning cashmeres with similar body weight (34.160.90 kg) were used, and evenly divided into four groups at random. The cashmeres in each group were fed with basal diet and supplemented with manganese of 0, 20, 40, and 60 mgkg-1 DM, respectively. Blood samples were taken to determine the contents of albumin (ALB), total protein (TP), immunoglobulin (IgA,IgG,IgM) and the activities of AST and ALT in the serum of Liaoning cashmere during nonpregnant period, 1 month and 4 month of pregnancy. The results showed that, adding manganese had no effects on activities of ALT, AST and VFI, and could increase body weight. The serum contents of ALB in 20 mgkg-1 DM manganese group were significantly higher than that in basal diet group, the serum contents of TP in 20 mgkg-1 DM manganese group were significantly lower than that in the other three groups, the serum contents of IgM in supplementing manganese groups were significantly higher than that in basal diet group during nonpregnant period (P0.05), and the contents of TP, IgA, IgG in 40 mgkg-1 DM manganese were significantly higher than that in basal diet group in 4 month of pregnancy (P0.05). It is concluded that dietary supplementation with manganese at 20 mgkg-1 DM (dietary manganese level is 60 mgkg-1 DM) during nonpregnant period and at 40 mgkg-1 DM (dietary manganese level is 80 mgkg-1 DM) during pregnant period can effectively improve immune performance of Liaoning cashmere.
Effects of Pennisetum americanumP.purpureume meal on the growth and meat quality of meat rabbit were studied by a randomized block experiment with 30 Fujian yellow rabbits (initial BW =1 742.2298.96 g ) which were divided into 3 groups with different Pennisetum americanumP.purpureum meal levels (Group 1, 10%; Group 2,30%; and Group 3, 50%), 5 replicates in each group, and 2 rabbits for each replicate. The results showed that, with the increasing of forage content, the average daily gain and carcass weight were decreased significantly(P0.05). However，there were signifcant differences among three groups (P0.05) for dressing percentage. The linolenic acid (ALA) content of rabbit meat increased significantly with increasing forage proportion in diets.Compared with Group 1, the ALA contents of rabbit meat increased 240.35% (Group 2) and 452.63% (Group 3) (P0.05),respectively. Besides, polyunsaturated fatty acids/saturated fatty acids (PUFA/SFA) obviously increased (P0.05), while n6 PUFA/n3 PUFA content decreased (P0.05).
Community structure of large size soil macrofauna were studied by quadrats statistical methods under four different land use types, including forest, forestmeadow, meadowsteppe and steppe in foreststeppe ecotone of Southeastern Inner Mongolia Plateau. There were 2 394 soil macrofauna individuals belonging to 22 orders, 8 classes and 3 phylums, and there were large changes in community composition and an obvious decreasing trend in the number of individuals. Besides, there were groups of large size soil macrofauna in the transition process from forest zone to steppe zone. It showed a significant differences（P＜0.05）in the number of groups and densitygroup index（DG）of large size soil macrofaun between different land use types. The number of macrofauna individuals in forest zone were significantly higher than that in forestmeadow, meadowsteppe and steppe zone, and the diversity index (H) in forest zone was significantly greater than that in steppe zone. In contrast, there were no significant differences in evenness index (J) between four land use types. In short, the forest zone had the highest number of individuals, groups,H and DG values, followed by the forestmeadow zone, meadowsteppe zone and steppe zone.
Based on the accumulation knowledge of teaching, research, practice of governments, and production managements in the city/county and township levels, this study was made on the development history of grassland rodent pests control and research. Five developing stages of grassland rodent pests control and research were proposed after comparative analysis, including ecological regulation stage, grassland rodent pests control based on hygienic epidemic prevention stage, chemical pesticides oriented stage, grassland integrated pests management (IPM) stage, and accurate and sustainable control stage. Each stage period was divided by transitional events, the representative countermeasures, prevention and control technologies, and the monumental significant academic activities. Besides, important works were also summarized in this study.
In order to investigate the effects of additives on fermentation quality of corn silage from different areas, North 410 variety planted in Harbin (HB), Chifeng Linxi (CF), Hohhot (H), Hebei Hengshui (HS) and Ningxia Yinchuan (YC) were taken as research subjects. The control group treatments of lactobacillus (0.000 5%) and treatments of cellulose treatments (0.001 5%), silaged in bags under vacuum were set separately and analysis was made after 45 days. The results showed that lactobacillus and cellulase treatments significantly lowered the pH value and acetic acid content, while boviously increased the lactic acid content (P0.05), and improved the fermentation quality and nutritional value of silage. Additive treatments significantly reduced NDF and ADF contents of corn silage (P0.05). The WSC contents of lactobacillus treatments in Harbin, Hengshui and Yinchuan were significantly increased (P0.05) and those in Yinchuan was the highest. The corn silage fermentation quality Flieg level of all areas were excellent.
Natural herbs are green additives with Chinese characteristics, which are riched in resources, and no resistance or drug residues. They have active ingredients of polysaccharides, organic acids glycosides,isoflavones with effects of growthpromoting, antioxidant, and improving immunity of animal.Developing Chinese herbal medicine as feed additives has become a hot topic at home and abroad. This article summarized researchs and application on Chinese herbal additives in livestock and poultry production.
Planting the green manure could provide nutrient, fertilize the soil fertility, improve soil structure, provide forage grass, safeguard food security, improve ecological environment, save energy and decrease consumption, and has an important development significance in China tradition agriculture. Green manure germplasm resources are rich in China, which mainly include Leguminosae, Gramineae, Brassicaceae, Compositae and etc. The green manure application models include intercropping model, rotation model, used model both as fertilizer and feed, orchard green manure planting model. Regional distribution of different models is different, because weather pattern and crops planter pattern are different. This paper summarized the research work on green manure main variety resources, main green manure application patterns and green manure effects in China and pointed out green manure future development directions.