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Based on precipitation data collecting at 21 stations from 1971 to 2000 and five topographic factors (altitude, slope, aspect, longitude and latitude) acquiring from three different resolution digital elevation model (DEM), the multivariate regression analysis, combined with GIS, was used to develop a precipitation prediction model for the Heihe river basin. The results of this study showed that the multivariate regression model explained 74.5% of the spatial variability of precipitation over the whole year, and this model had better explanation precipitation for wet season (MaySeptember) than the whole year and dry season. Precipitation during dry season was difficult to simulate owing to little rainfall and a different synoptic system. The 100 m resolution model in the three periods were better than other resolution model to explain the precipitation because the spatial distribution of precipitation was uneven. The 100 m resolution model predicted that the precipitation increased from below 200 at the northwest regions to 700 mm at southeast regions, indicating that a precipitation line exit was observed from northeast to southwest. The 500 m resolution model predicted that the rainfall was ribbon boundaries with a certain degree shift. The 1 000 m resolution model predicted rainfall distribution with a big error. The model established in this study could be potentially applied to other mountains; however, improving the model accuracy was necessary in the future.
Based on data sets of soil organic carbon (SOC) extracted from the literature about grassland area and different managements, the SOC changes of grassland in the Xilinguole, Inner Mongolia from 2000 to 2007 were estimated to understand the contribution of grassland management on SOC by two approaches, in which one was the IPCC Tier 2, and the other was transfer matrix of SOC under various managements. The results of this study showed that SOC of grassland in the Xilinguole increased by 20.85-29.80 Tg with an average rate of 2.61-3.72 Tg/a from 2000 to 2007. The increment of SOC in the Dongwuzhumuqin, Xiwuzhumuqin, Sunitezuo, Suniteyou and Abaga, and Xilinhaote city was more than 80% of total increment of SOC. Correlation analysis indicated the SOC estimated by the IPCC Tier 2 showed a similar trend with those estimated by transfer matrix approach, while the total SOC estimated by the IPCC Tier 2 was approximately one third of those estimated by transfer matrix approach. The estimated annual SOC was not consistent between two approaches. The annual increment of SOC before the third year was greater than that after the third year when the IPCC Tier 2 was employed, while the increment of SOC after the fifth year was higher than that before the third year when the transfer matrix approach was employed.
An experiment was conducted to determine the effect of inoculation of nonsymbiotic azotobacteria BC2 isolating from wheatgrass (Agropyrom cristatum) on the growth and fixing nitrogen. The results of this study showed that BC2 inoculation increased the dry weight of wheatgrass and nitrogenfixing capability with 42.55 mg/kg in the entire system when compared to the control. The effectiveness of inoculation was better due to soil sterilization and the total nitrogen content of sterilized soil with 80.95 mg/kg was twice of the unsterilized soil. This study also showed that BC2 inoculation improved the N fixation efficiency via increasing the soil carbon source.
In recent years, the number of golf course is increasing and the construction of golf course is prevalent. The unreasonable construction method, however, causes the great negative effect on environments around the golf course. Therefore, it is urgent to construction an environmentallyfriendly golf course by scientific and more efficient way. On the basis of characteristics of golf course in the forest land, this study proposed the clearance methods consisted of four stages, drawing clearance, complete clearance, partial clearance, temporary clearance, and the processes and tasks of each stage were introduced in detail. From start to completion of golf courses, measurement was considered as a key task in the construction process, and the theory and application of the measurement around the clearance engineering work was also described in this study.
Field experiments were conducted from 2009 to 2010 to determine the injuring of perennial ryegrass (Lolium perene cv. Overseed 2# ) overseeded in seashore paspalum (Paspalum vaginatum cv. Salam) by mixing application of herbicides with fertilizer（The trade product contained 4.5 g/m2 of N plus 1.5 g/m2 of P2O5 and 3 g/m2 of K2O）. This study showed that Chlosulfuron at 0.027 kg ai/ha and sulfosulfuron at 0.01 kg ai/ha resulted in excellent seashore paspalum safety when applied alone or mixing with fertilizer in Nov. 2009. While neglecting minor leaf discoloration of turf was demonstrated at 2 WAA (Weeks After Application) by diuron at 1.6 kg ai/ha alone. The dormancy stage of turf had been prolonged for 5 days when mixing diuron and fertilizer comparing with the untreated plots. The ryegrass eliminated at 2-3 WAA caused by 3 herbicides both along using or mixing with fertilizer treated in late May, 2010. No injuring of seashore paspalum caused by chlosulfuron at 0.027 kg ai/ha alone or mixing with fertilizer. Neglecting tiny leaf discoloration of turf occurred with the sulfosulfuron at 0.01 kg ai/ha alone or mixing with fertilizer and recovered 5-6 WAA. Moderate discoloration with thickness of turf caused by diuron 1.6 kg ai/ha at 2 WAA and recovered at 7 WAA. Visible severe leaf discoloration with some necrosis of turf occurred due to mixing application with diuron 1.6 kg ai/ha and fertilizer lasting from 2 to 5 WAA and recovered at 9 WAA with remarkable thickness.
The carbon cycle and carbon storage becomes a hot spot in the filed of geoscience and global change in recent years, in which the grassland ecosystem as the unique type of ecological system is the most important and the most complicated part affected by man. This study reviewed the role of grassland in the global change, the relationships between the change of CO2 concentration and missing carbon sink and the grassland ecosystem, emphasized on the carbon circle process of the terrestrial ecosystem and grassland ecosystem and factors affecting the carbon circle. This study also summarized the carbon storage value and distribution pattern of grassland ecosystem in China, and the relationships between the source and sink in the process of carbon circle by current documents and papers, and then proposed the some current problems and a perspective of carbon circle, which would provided some useful information for carbon circle and carbon storage of the grassland ecosystem in China.
Primers were designed based on the conserved region of cbf, derb, myb in Gramineae plants. RTPCR was used to clone transcription fragments from Agropyron cristatum leaf and 3 fragments of 548 bp, 862 bp, 319 bp were firstly obtained and named as ACcbf，ACdreb，ACmyb, respectively. Semiquantitative RTPCR was conducted to test the expression mode of the three genes under cold and drought stress. The result of this study showed ACcbf was sensitive to cold stress, and more or less, responsed to drought, and ACdreb was sensitive to both drought and cold, and ACmyb was sensitive to drought, but insensitive to cold.
14 morphological traits of plant ear were used to analyze the morphological diversity of plant ear among 8 Elymus species consisting of 101 populations. The results of this study showed that the phenotypic features were different among populations of different species from the same area and different populations of the same species from different regions, indicating that 14 morphological traits were different among 8 Elymus species. The E. excelsus was maximum in ear length, ear width, spikelet length, spikelet width, spikelet number, florets number per spike, awn length of the first lemma, the first glume length and the first node length of the main rachis, and the E. atratus was minimum in ear width, length of the first lemma and awn length of the first glume. The coefficient of variance of 14 ear traits was in order by the first glumedistance between boot leaf and earthe first glume lengththe first node length of the main rachisthe first glume widthawn length of the first lemmaear widthspikelet numberflorets number per spikespikelet widthear lengthspikelet lengthawn length of the first lemmathe first palea length. The totally genetic diversity index of the total populations of each species showed a decreasing trend by E.nutansE.sibiricusE.dahuricusE.tangutorumE.excelsusE.cylindricusE.breviaristatusE.atratus and the average genetic diversity index among species was E.sibiricusE.excelsusE.nutansE.dahuricusE.atratusE.breviaristatusE.cylindricusE.tangutorum. The phenotypic differentiation coefficient was in order with E.tangutorumE.cylindricusE.dahuricusE.nutansE.sibiricusE.excelsusE.breviaristatusE.atratus. This study suggested that the diversity of 8 species in Elymus developed by diversity within population and diversity among populations, and contribution of diversity within population and diversity among population was different.
A field experiment was conducted to determine the suitability of chicory (Cichorium intybus) cultivars (Commander, Puna) by measuring the phenophase, forage yield and nutritional ingredient at three points in Panxian County. The results of this study showed that the 2 introduced cultivars performed well at the local environment, indicating that they completed the whole growth cycle with over 75% of winter and summer surviving rate and showed a strongly resistant pest. The forage yield and quality of Commander was higher than that of Puna, indicating that the fresh yield and the dry matter yield of Commander was higher than that of Puna with 14.99% and 19.20%, respectively. This study suggested that the Commander chicory was considered as the high quality and high production forage, which could be extended in the Panxian County, Guizhou Province.
The objective of this study was to determine the effects of temperature, light and sowing depth on newly seed germination of switchgrass (Panicum virgatum cv. Alamo) planting in the Beijing for 3 years, which was introduced from the United States in 2005. The resulted of this study showed that the temperatures from 30 ℃ to 35 ℃ encouraged the seeds to germinate faster, and increased the maximum germination percentage, germination vigor, germination index when compared to the low temperature from 20 ℃ to 25 ℃ and the high temperature with 40 ℃. The light and darkness treatments did not affect the germination percentage of Alamo seeds, but encouraged the seeds to germinate faster and increased the germination vigor and germination index. The treatments of differently sowing depths, from 2 mm to 16 mm, were very uniform and efficient since they not only encouraged the seeds to emerge but also increased the emergence percentage and emergence index of switchgrass seeds in comparison with 0 and 32 mm sowing depths.
Thermopsis lanceolate is the poisonous and medicinal plant resource which often grows in north pasture of China. The present study analyzed the influence of light, temperature, soil moisture and sowing depths on the seeds germination and seedlings growth of T. lanceolate. The results showed that 25 ℃ was the most fitting temperature for seed germination under constant light and alternating light (16 h) and dark (8 h) conditions; The alternating day/night temperature (25 ℃/15 ℃) was the most appropriate temperature treatment for seed germination under the alternating light (16 h) and dark (8 h) condition; T. lanceolate seeds germination was not sensitive for light; The most proper soil water content and sowing depth was 7%~12% and 0.5~2.0 cm ,respectively for the germination of T. lanceolate seeds.
A field survey was conducted to determine the effect of two new herbicides on important values and plant diversity of Stellera chamaejasme-Kobresia humilis grassland communities. This study showed that two herbicides (Langdujing and Mielangdu) greatly affected the important values of plant species of S. chamaejasme-K. humilis grassland communities, indicating that the important values of K. humilis, Stipa purpurea, Poa crymophila, Leymus secalinus increased gradually and these plant species became the dominant, but the S. chamaejasme and Thermopsis lanceolata disappeared. LangDujing and Mielangdu caused one and five plant species to disappear, respectively. Two herbicides decreased the plant diversity of grassland communities, indicating that the Langdujing and Mielangdu reduced the richness index by 15.2% and 31.4% respectively in the coming year. The Mielangdu significantly decreased the dominant index (P0.05) but Langdujign did not affect the dominant index. The evenness index was significantly different between Langdujingd and Mielangdu (P0.05). This study suggested that Mielangdu had stronger influence than Langdujing on plant diversity and important values of grassland community.
Nostoc commune is a nitrogenfixing blue algae with reversibly characteristic and it plays an important role in the nitrogen cycle of the natural grassland. A simulation experiment was conducted to determine the effects of rainfall and grazing intensity on the growth rate of N. commune in this study. The results of this study indicated that moderate grazing benefited the growth of N. commune, and its growth rate was three times and four times at early and late growth stage of nograzing, respectively, and the lowest N. commune growth rate was observed in the nograzing treatment. Rainfall showed different effects on the early growth rate and the late growth rate of N. commune, indicating that the high rainfall significantly increased the early growth rate, and the early growth rate in highrainfall treatment was fourteen times that of low rainfall, and moderaterainfall significantly increased the late growth rate. The highest early growth rate of N. commune was presented in the treatment with moderate grazing and highrainfall and the highest late growth rate of N. commune was presented in the treatment with moderate grazing and averagerainfall.
The five grazing levels (i.e. no grazing(CK), grazing light(LG), moderate grazing(MG), heavy grazing(HG) and extreme grazing(EG)) was used to investigate the effect of grazing intensity on community characteristics of Leymus secalinus grassland for determining a reasonable grazing capacity, which further optimize the utilization patterns of grassland. This study showed that the cover and frequency of the dominant species L. secalinus and Potentilla ansrina were maximum in the MG, but the changes of density and height were not significant(P0.05)；the cover of Artemisia lavandulaefolia, Saussurea amara and Taraxacum mongolicum were maximum in the MG. As grazing intensity increased, the dominance of the main species had downward trend in this grassland and the dominance of individual species resistance to grazing and the ability to propagate species increased gradually; the grassland biomass increased with the decrease of grazing intensity, but had increasing trend in the MG. After twotime of grazing, The Margalef species richness index, ShannonWiener diversity index, Simpson dominance index and Pielou uniformity of grassland communities were significantly different (P0.05). In MG, the species richness was maximum. The grassland community had high species richness and dominance, but the uniformity was low in the MG.
The improving efficiency and accuracy of vegetation cover is very important because the cover is a necessary parameter to estimate the health of grassland ecosystem. This study proposed a quickly calculating vegetation cover method by Excess Green Index and semiautomatic threshold (ST). Efficiency of the algorithm was evaluated by comparing with Maximumlikelihood supervised classification (MC) and HueSaturation method (HS). 32 digital images were used to test the efficiency of three methods. Vegetation cover estimated by each method was regressed with accurate cover obtained by visual interpretation via slope, intercept, and regression coefficient. The three methods did not consider nongreen component of vegetation, resulting in slightly underrating problem. In conclusion, ST not only achieved similar accuracy with MC but also avoided overrating problem of MC when cover was low. ST showed little human intervention, and achieved accurate cover; however, it failed to extract greygreen vegetation.
A field trial was carried out in Hubei province, central area of China to determine the effect of fertilization on the yield and forage quality of annual ryegrass (Lolium multiflorum) by comparing crude protein (CP), ether extract (EE), nitrogen free extract (NFE), acid crude fiber (CF), crude ash (CA) and gross energy (GE). The results of this study showed that fertilizer recommendation 1 (N450P45K90) and fertilizer recommendation 2 (N540P180K360) significantly improved the fresh forage yield of ryegrass, which were 2.6 times and 3.1 times higher than that of CK, respectively. The amount of dry matter accumulation per day firstly increased, and then decreased with the growth of ryegrass, and achieved the maximum with 223.9 kg/（hm2d） at the 130 d after sowing. The yield of fertilizer recommendation 2 increased by 12.0% compared to that of fertilizer recommendation 1. Fertilization increased the content of P, Ca, CP and EE in ryegrass, and decreased the content of NFE. Compared to fertilizer recommendation 1, fertilizer recommendation 2 improved the content of CP, EE and CA, while decreased the content of CF and NFE of three times clipped ryegrass. The fertilization significantly increased yield of CP, EE, CA, CF, NFE and GE, indicating that fertilizer recommendation 2 did better than fertilizer recommendation 1.
A culture experiment was conducted to compare the quality and yield of different genotype Glycyrrhiza uralensis for selecting the fine licorice lines of G. uralensis by measuring the biomass, glycyrrhizic acid contents, flavoniods, polysaccharide, soluble sugars, amino acid and protein. This study showed that the yield and the glycyrrhizic acid content of the strains with good quality and high yield were 3 and 1.6 times that of the strains with poor quality and low yield, respectively. The comprehensive analysis showed that the plant height was not correlative relationship with the quality and stem color, while the yields of highgreen plants were higher than that of lowpurple ones.
The biological detection techniques were used to determine the allelopathy effectiveness of leaf and stem extracts from three varieties of Lolium multifolorum on Sardi 10 of Alfalfa. The results of this study showed that the allelopathy effectiveness of three varieties of L. multifolorum on alfalfa were different. The extract from Barextra leaf encouraged Sardi 10 seeds to germinate. The 10.0% and 7.5% concentrations of extract of Barmega leaf inhibited Sardi10 seeds to germinate. This study also found that the allelopathy effectiveness of extracts from stem and leaf was different, indicating that the stem extracts of Jumbo and Barextra inhibited Sardi 10 seeds to germinate while the leaf extracts of Jumbo and Barextra encouraged Sardi 10 seeds to germinate. Different concentrations of extracts showed different allelopathy effectiveness, indicating that the 10.0% concentration extracts of L. multifolorum showed a positive effectiveness and the 5.0% concentration extracts of L. multifolorum showed a negative effectiveness on seed germination, root growth and seedling fresh weight of Sardi 10 of Alfalfa.
A field experiment was conducted to determine the effect of fertilizer, irrigation and pinching on growth and development of Lavender (Lavandula angustifolia) seedlings in the Dingxi district of Gansu province. The results of this study indicated that the three management measures greatly affected the growth and development of Lavender seedlings, and showed an order with irrigation＞fertilizer＞pinching. The irrigation and fertilizer remarkably increased the plant height, canopy width, tillers per plant, and heads per plant of Lavender seedlings. The pinching remarkably increased the tiller numbers per plant, but decreased the growth and heading rate at the earlier growth stage. The ditch fertilizer and broadcast fertilizer shared a similar effectiveness on the growth and development of Lavender seedlings, but the effect of nitrogen, phosphorous, mixture of nitrogen and phosphorous on Lavender seedlings was different, indicating that the nitrogenous fertilizer and mixed fertilizer of nitrogen and phosphorous were better than phosphate fertilizer, which implied that the nitrogenous fertilizer was the main fertilizer for growth and development of Lavender seedlings. This study suggested that the irrigation was the most important factor influencing the growth and development of Lavender seedlings in the semiarid areas and fertilization management followed it, whereas the pinching was a supporting management measure.
the micronucleus test was used to determine the effects of detergent concentrations on root tip cells teratogenesis of pea by measuring the cytotoxicity and the genotoxicity. In this study, the dilution detergent concentrations with 200 volume (detergent/distilled water), 100 volume, 10 volume and 5 volume, respectively, was added into pea root tip and root point cell mitosis index, the micronucleus rate and chromosomic aberration rate were investigated and made micrography at 24 h and 48 h. The results of this study showed that the root tip cell mitosis index obviously decreased and had the obvious dosagetime effectiveness, and the micronucleus rate and the chromosomic aberration rate increased in low concentrations, but they decreased in high concentrations and they did not have the obvious dosagetime effect along with the increase of detergent diluted concentration and with the lengthens of treatment time. The cell chromosome bridge, micronucleus and many kinds of chromosomic aberration type were caused with different concentrations detergent, and the root tip cell chromosome damage was created as well. This study suggested that the different concentrations detergent had some certain heredity toxicity to the pea root tip cell.
Tianzhu County locates at the edge regions of QinghaiTibetan Plateau, and grassland in this County generally degrades, in which degradation area of grassland counts for 34.4％ of total grassland area. The present cover, height and yield reduced by 11.11%, 41.7% and 30.4% when compared to those in the 1950s, and the gramineous plant in grassland communities greatly decreased and the unpalatable plants increased. This study pointed out that the climate warming, overgrazing, pest and rodent, and illegal utilization contributed to the grassland degradation. Based on current situation of grassland, this study proposed the some advices of sustainable utilization of grassland.
Tianzhu County with vast alpine grassland is one of Gansu province's important pastoral areas. This study reviewed the causes of grassland degradation at broad and home, and then proposed that the fragile ecological environment was the intrinsic factors, which caused alpine grassland to degrade in the Tianzhu County. The human activities such as disturbance and unreasonable utilization were the major driver for grassland degradation, and global warming accelerated the grassland degradation. This study also proposed that the loss of livestock manure, allelopathy among plants and selfallelopathy were important causes of grassland degradation. Finally, this study put forward some measures to restore the degraded alpine grassland, which included rational carrying capacity and the increase of marketing rate for livestock, and include fencing and establishment of artificial grassland for improvement grassland. Meanwhile, the rodents and pests integrated control, intellectual resources, and extension of science and technology would be benefit the restoration of alpine grassland restoration.
Alfalfa acts the very important roles in the agriculture, animal husbandry, and the ecological construction in the arid and semiarid areas of northwest China. To provide the references for improving the salt and drought tolerance of alfalfa, this paper reviewed the recent results involving the physiological mechanisms of alfalfa resistant to salt and drought, and the assessment of its salt and drought tolerance.
A series of measurements were used to optimize the producing system of beef cattle grazing on mixture pasture of cocksfoot and white clover, and these measurement included 24 hours rotation grazing, seasonal adjustment of stocking rate, sustainable application fertilizer, weed, fodder supplementary. The soil nutrients, intensity of pasture growth, standing biomass, component, nutrients, weights and daily gain of beef cattle were monitored in the process of experiment. The results of this study showed the beef cattle was good and the economic benefit per unit was 1 135 Yuan/ha when the stocking rate was 1.4 cattle unite/ha and the growth biomass of pasture was above 8 077 kg/ha under 24 hour grazing conditions. These optimal measurements were advantageous to sustainable utilization of pasture. Finally, this study proposed the effective advices to solve present problems of grazing system of beef cattle.
The trade pattern of alfalfa forage products in China is changing due to rapid change of supply and demand of alfalfa products at domestic and international market. How to healthy develop alfalfa industry is a hot issue by taking full advantage of supply and demand pattern of alfalfa forage products. Based on trade characteristics and status of alfalfa forage products, this study pointed out the further developing chance and future direction of alfalfa industry, and further proposed some policy advice of alfalfa industry development.
The meteorological data and the participatory rural appraisal were used to analyze the climatic change characteristics in the Alxa desert region, and sampling herders was questioned to inquire about basic family status of Alxa herd, and their perception for climate change and countermeasures. The results of this study showed that the mean annual temperatures significantly increased in the Alxa left and right banner, but the mean annual precipitation faintly increased with fluctuation in the past 50 years. The herd perception of mean annual temperatures rise was the same as meteorological analysis. The herders recognized that grassland environment deteriorated because grassland production reduced and plant species receded in recent ten years. The level of grassland sandy soil, pests and mice increased, but surface water decreased. Extreme weather events were frequent in recent ten years, which seriously affected animals health, production and grass growth. The herdsmen took major action on providing sufficient feed in autumn during domestic animal production to face the climate change, meanwhile kept up production in captivity. Future climate change would continue and its impact on production and living of herdsmen would also continue. Finally, this study proposed the countermeasures to help herders for enhancing their adaptive capacity to climate change.
With the continual reform of the high education and the development of modern education concept, the undergraduate training objective with extensive, broad and compound features becomes consensus, and the curriculum setting plays an important role for achieve this goal to benefit personnel training and employment. As a case of study, the undergraduate training scheme of pratacultural science major in Sichuan Agricultural University was used to estimate the status of professionals training of grassland science and some ideas were proposed to establish the training system of interdisciplinary talent in the future, which would improve the currently undergraduate training system of grassland science in China.
It is important to seek an approach to effectively reduce the fiber content and improve palatability and the forage value of Caragana korshinskii for improving the current utilization status of C. korshinskii growing at the forbidden grazing and restgrazing areas. The puffed technique was used to effectively reduce the lignin and cellulose content of C. korshinskii in this study by comparing the nutrients of C. korshinskii. The atmospheric pressure, temperature, the moisture content of raw material, and the cut length were applied to optimize the processing techniques of puffed C. korshinskii in this experiment. The results of this study showed that the 1.0 MPa atmospheric pressure, 170 ℃ temperature, 30% of the moisture content of raw material, 2 cm the lengths was optimal conditions for the puffing C. korshinskii, in which the ADL content of C. korshinskii was the lowest and the digestibility of C. korshinskii was largest.
The steppe is one of national strategic resources, and plays a vital role in ecological security and animal production. Rational utilization of steppe resource is key to steppe management by perfecting and enforcing the grassland laws and regulations. This study pointed out the main problems and troubles in the process of enforcing grassland laws and regulations, and then proposed the development direction and perfecting advice of grassland laws and regulations.