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FPAR(Fraction of Absorbed Photosynthetically Active Radiation) is one of the main plant physiological parameters. FPAR estimation models were established based on both ground measured data and NDVI extracted from HJ-1CCD (Chargecoupled Device, CCD) and Landsat8OLI (Operational Land Imager, OLI) image, respectively. And then, the differences in retrieved FPAR from CCD and OLI data were comparatively analyzed and quantitatively assessed. There was a outstanding positive correlation between measured FPAR and NDVI from CCD and OLI data. For each ESU(Elementary Sampling Units), FPAR retrieved from CCD and OLI data were significantly consistent with each other only with small difference. FPAR retrieved from CCD data was consistent with that retrieved from OLI data with similar distribution trends and small difference if excluded the area being affected by clouds and cloud shadow in the entire study area. The results provided reference and guidance for further FPAR research in the studied area.
Spectral characteristics of grassland plants have important implications for the identification of species. In the present study, spectral differences with 5 species of typical poisonous weeds of Heteropappus bowerii, Ligularia sagitta, Thermopsis lanceolata, Anaphalis lactea and Potentilla anserina in Gannan alpine meadow were analyzed using canopies spectra and parameterized characteristics. Although the tendencies of the original spectral curves of these poisonous weeds were similar, these weeds can be easily distinguished by indices as red valley,green peak, red edge, water uptake, spectral index, and spectral reordering after the first derivative spectra and reordering of the original spectral curves. These results suggested that vegetation classification based on spectral analysis had important significance on the remote sensing research, vegetation investigation and classification of Gannan alpine meadow.
The CO2 emission in Carex tristachya alpine wetland with different water conditions in Bayinbuluke Swan Lake, Xinjiang Tianshan Central in summer were measured with portable soil respiration measurement system (CIRAS-2-SRC) made by British PP system company. The results showed that the biomass of humid area was greater than that of the drying area. The CO2 emission of drying area was higher than that of the wet area. The diurnal variation curve of CO2 emission from dry area was unimodal curves with the highest points occurred between 14:00 and 16:00 (1.185 0 g CO2m-2h-1). The diurnal variation curve of CO2 emission from wet area were bimodal curves with the highest points occurred at 12:00 and 16:00, respectively, and the highest value was 1.024 0 g CO2m-2h-1. The litter content of biomass had effects on soil CO2 emissions under different water conditions, however, soil temperature was the major limiting factor for CO2 emissions. CO2 emissions had a significant positive correlation with surface soil temperature in the dry area （P0.01）and did not have significant positive correlation with soil humidity（Pwet area=0.997,Pdry area=0.409）.
Based on catastrophe theory, catastrophe progression method of natural grassland classification was put forward to provide reference for the quantitative study on natural grassland classification. Three factors including ecological situations, reproduction abilities and economic conditions of natural grassland were taken into accounted synthetically in this study, and the hierarchical index system for natural grassland classification was constructed. On the basis of the relevant researches, the natural grassland was divided into 3 grades: temperate desert type, temperate steppe type and meadow grassland type, and 18 natural grassland samples from western Junggar Basin, Sinkiang, China, were selected as the training samples, and the catastrophe progression recognition criteria were presented. The additional 13 natural grassland samples were selected as the testing samples, and evaluated to verify the feasibility and reliability of the proposed catastrophe progression recognition criteria. The study showed that catastrophe progression method could better reflect the resources attributes of natural grassland, and the classification results of 13 natural grassland testing samples were reasonable, and agreed well with that of grey relational analysis method, projection pursuit method, projection pursuit dynamic cluster method, set pair analysis method, and the selforganizing feature maps (SOFM) neural network method.
Coolseason turf grass in Lanzhou including perennial ryegrass (Lolium perenne cv. Premier and L. perenne cv. Panterra), Kentucky bluegrass (Poa pratensis cv. Barvictor and P. pratensis cv. Barrister), tall fescue (Festuca arundinacea cv. Barlexas and F. arundinacea cv. Easy Care), white clover (Trifolium repens cv. Nanouk) and alfalfa (Medicago saliva cv. Algonquin) were irrigated with both tap water and reclaimed water from Lanzhou University Yuzhong Sewage Treatment Center to test the effects of reclaimed water on the soil characteristics. The results showed that reclaimed water could significantly improve (P0.05) soil available nutrient and total nitrogen and very significantly increase (P0.01) soil organic matter. There was no significant difference between total phosphorus contents of perennial ryegrass with tap water and reclaimed water treatments. Total potassium and sodium content of soil with reclaimed water treatment was significantly higher (P0.05) than those of soil with tap water treatment except with those of alfalfa. In conclusion, reclaimed water have rich nutrition elements which can be applied for turfgrass irrigation in Lanzhou.
The regeneration systems of Chrysanthemum morifolium cv. ziyan and C. morifolium cv. niu 9722 were established with the aseptic stems with axillary bud as explants and basic medium with different concentrations of 6BA and NAA. The results showed that the optimal sterilization method was 2% NaClO for 6 min for ziyan and 2% NaClO for 8 min for niu 9722. The optimal medium for adventitious bud induction from leaves of ziyan was MS+6BA 2.0 mgL-1+NAA 1.0 mgL-1 with the callus induction ratio of 100%, the adventitious bud differentiation ratio of 92.22% and the reproduction coefficient of 7.60. The optimal medium for adventitious bud induction from leaves of niu 9722 was MS+6BA 2.0 mgL-1+NAA 0.5 mgL-1 with the callus induction ratio of 100% and the adventitious bud differentiation ratio of 45.59%. The optimal medium for stem proliferation of niu 9722 was MS+6BA 2.0 mgL-1+NAA 0.5 mgL-1 with the average multiplication coefficient of 10.05. The optimal medium for rooting of ziyan was 1/2 MS+NAA 0.2 mgL-1 with the rooting rate of 100% and the average root number of 15.50. The optimal medium for rooting of niu 9722 was 1/2 MS+NAA 0.3 mgL-1 with the rooting rate of 100% and the average root number of 14.87. The transferred plants grew well with survival rate of 100%.
In the summer of 2013, Ningbo suffered the highest temperature in 60 years which lasted for long time associated with the drought. The injury degree and recovery situation of 18 Hemerocallis hybridus accessions under this weather conditions were recorded and the heat resistance of these germplasm were evaluated by graycorrelation analysis. There were difference between the field performance of different H. hybridus accessions under this continuous heat and drought. The growth of the accessions with strong heat and drought resistance were not affected by this weather. The growth of the accessions with weak heat and drought resistance were affected and performed yellow and wilt leaves. The indices included the growth, summer survival rate, overall posture, heat injury index, leaf color and ornamental value were selected as evaluation indices of heat resistance. The result showed that the accessions of X16, X8, X11 and X15 had stronger heat resistance. Their correlation degrees with the ideal species were over 0.9 which were suitable for cultivation and population in Ningbo area. The accessions of X1, X18 and X12 had weak heat resistant which were suitable for understory flowers as their faster recovery.
In order to study the variation characteristics of the difference between evaporation and precipitation during the grass growing season in Maqu County, the PenmanMonteith model was employed to compute the potential evapotranspiration based on the meteorological data from 1971 to 2010 in Maqu weather observation station. The results indicated that the difference between evaporation and precipitation in Maqu increased with the ratio of 12.1 mm10 a-1 during the grass growing season. The difference between evaporation and precipitation in the start and end period of growing season increased with the ratio of 3.5 and 11.2 mm10 a-1, respectively, whereas the difference decreased in the middle period of growing season with the ratio of -2.6 mm10 a-1. The water deficit occurred in the 1990s due to the increase of potential evapotranspiration and the decrease of precipitation. Water deficit was one of the most important impact factors for the grassland degradation and environmental deterioration in Maqu County.
Delta-pyrroline-5-carboxylatesynthetase (P5CS) is the key enzyme for glutamic acid biosynthesis from proline under plant osmotic stress. In the present study, the fulllength complementary DNA (cDNA) sequence of one P5CS gene (designated SaP5CS1) in Sisybrium altissimum was characterized by RACE and realtime PCR (RT-PCR). The complete cDNA sequence of SaP5CS1 comprised 1 907 bp with an open reading frame (ORF) of 1 719 bp, and encoded a P5CS precursor peptide of 573 amino acids with a predicted molecular weight of 156.279 kDa and isoelectric point of 4.95. In the sequence alignments of P5CS genes, the amino acid sequences of SaP5CS1 exhibited 98% and 96% sequence identities with Brassica napus P5CS1 and Arabidopsis thaliana P5CS1, respectively. Realtime fluorescent quantitative PCR (qRTPCR) analysis showed that SaP5CS1 gene was highly upregulated in both leaves and roots at different drought stress treatment time points. The cloning and sequence analysis of SaP5CS1 gene might lay a foundation for the further function analysis and molecular breeding.
The physiological and biochemical response of creeping bentgrass to cadmium stress were studied in the present study. The results showed that cadmium stress exhibited inhibitory effects on creeping bentgrass initial growth and the inhibition effects increased with the cadmium ion concentration increased. When cadmium ion concentration was 50 mgL-1, seed germination rate, shoot length, root length and seedling fresh weight were 47%, 87%, 54% and 83% of that of control, respectively. Seed germination was completely inhibited by 400 mgL-1 cadmium. Cadmium ion had significant effects on contents of chlorophyll, malonaldehyde(MDA) and activities of superoxide dismutase(SOD), peroxidase(POD). With cadmium ion concentration increased, chlorophyll content decreased whereas MDA content increased gradually. When cadmium ion was 200 mgL-1, chlorophyll content and MDA content were 37% and 864% of that of control, respectively. SOD activity reached maximum of 1 314 Uh-1g-1 with lower cadmium ion concentration of 50 mgL-1. SOD activity decreased with higher cadmium ion concentration although it was still higher than the control. POD activity had similar variations with SOD activity and reached maximum of 225 Us-1g-1 with lower cadmium ion concentration of 100 mgL-1. The response of the 90 day old plants germinated from seeds treated with cadmium (2~100 mgL-1) was similar with seedlings. With cadmium ion concentration increased or cadmium stress period extended, chlorophyll content decreased whereas MDA content increased gradually and both SOD and POD activities increased first and then decreased.
A pot experiment was conducted to study the effects of the combined cadmium and lead stress on physiological characters of kentucky bluegrass seedlings. The results showed that the Cd2+ stress had significant (P0.05) effects on the indices including leaf cell membrane permeability, malonaldehyde (MDA) content, chlorophyll content and proline content. leaf cell membrane permeability, MDA and proline content of seedling with 80 mgkg-1 Cd2+ treatment were significantly(P0.05)higher than those of seedling with 40 mgkg-1 Cd2+ treatment whereas the chlorophyll content result was reverse. The Pb2+ stress had significant (P0.05) effects on proline content, leaf cell membrane permeability after 10 d and 20 d treatments and MDA content after 20 d and 30 d treatments. Leaf cell membrane permeability, MDA and proline content of seedling with 1 000 mgkg-1 Pb2+ treatment were significantly(P0.05)higher than those of seedling with 600 mgkg-1 Pb2+ treatment. The significant interaction of Cd2+ and Pb2+ stress was observed in MDA content after 30 d treatment and proline content after 20 d and 30 d treatments. With the extension of heavy metals stress time, chlorophyll content firstly increased and then decreased, leaf cell membrane permeability, MDA and proline content increased gradually.
In order to improve pod retention rate and seed yield of alfalfa, effects of nitrogen fertilizer application time on pod retention rate, 1 000seed weight, seed yield of Medicago sativa cv. Xinmu No.4 were studied. The results showed that the pod retention rate, the 1 000seed weight and seed germination rate with the treatment of fertilized at returning green stage were higher than that in the other treatments which was 63.87%, 2.01 g and 85.33%, respectively. However, the pods number per inflorescence and pod retention rate of this treatment were lower than that in the other treatments. The seed yield was highest if fertilized at the budding stage which was 802.16 kgha-1 and 2.05 times of control and the seed yield was higher if fertilized at branching stage which was 641.29 kgha-1 and 1.64 times of control. These results provided a theoretical basis for rational fertilization of alfalfa seed field.
Energy plants are suitable to be planted in semiarid Loess plateau with huge potential production capacity. However, Loess plateau is famous as fragile ecological environment which limited production capacity as water deficit. In order to explor highyield energy plants with watersaving, the dry matter distributions of Miscanthus sinensis and Panicum virgatum under different soil moisture(75%, 55%, 35% of field moisture capacity) were studied. The results showed that the root biomass, shoot biomass and total biomass were significantly affected (P0.05) by both moisture contents and species. The biomass of M. sinensis was significantly higher (P0.05) than that of P. virgatum for all treatments. The biomass of both species significantly decreased (P0.05) with the decrease of soil moisture content. The soil moisture contents had significant effects (P0.05) on rootshoot ratio of P. virgatum whereas it has little effects on that of M. sinensis. With the lower moisture content, P. virgatum could strengthen the absorption of water and nutrients with more root number and higher rootshoot ratio. For root biomass, shoot biomass and total biomass of the both energy plants, there was no significant difference between control and the treatments with 75% and 55% of soil moisture capacity. M. sinensis and P. virgatum could use water more efficiently under 55% soil moisture capacity.
In order to comprehensively evaluate agronomic characteristics of sweet sorghum (Sorghum bicolor) in coastal soil in Jiangsu Province, 19 varieties of sweet sorghum were analyzed by gray relational grade involved in emergence rate, growth period, fresh to dry ratio, sugar brix, plant height, stem diameter, 1 000grain weigh, lodging rate, fresh forage yield and grain yield. The results showed that Zhongke 4 was the best variety with the highest weighted relational grade (0.831) and the excellent characteristics of good emergence, partial early maturity, high yield, lodging resistance and adaptability. The weighted relational grades of NJ003 was 0.779 and that of SN009 was 0.747 which occupied the second and third place, respectively. The evaluation results were essentially identical with the field performance of the tested varieties. Therefore, the comprehensive evaluation provided a scientific evidence for sweet sorghum breeding in the region.
A preliminary assessment of morphology characteristics of 26 capetgrass (Axonopus compressus) accessions were conducted in the present study. The results showed these carpetgrass accessions performed a very rich diversity of morphology characteristic. There were significant positive correlations or negative correlations between these different indicators (P0.05). The variant coefficient of fertile tillers was 71.11% which was the highest in all morphology characteristics. The variant coefficient of seed length was 4.41% which was the lowest with the average of 19.29%. There was very significant difference (P0.01) between these indices. These tested 26 carpetgrass accessions were divided into three groups base on these morphology indices, which were high density of inflorescence, low density of inflorescence and intermediate type, respectively.
The yield, land equivalent ratio and economic benefit of Brassica napobrassica and Solanum tuberosum intercropping were studied under field condition. The results showed that the intercropping with interval underground had the highest yield of 159 411.30 kgha-1 and intercropping with underground film interval had yield of 147 431.44 kgha-1. The land equivalent ratio of B. napobrassica and S. tuberosum intercropping were 1.76 and 1.63, respectively, which suggested that intercropping had a yield advantage than monocultured. The economic benefit of intercropping was up to 50 802 CNYha-1, which showed that the intercropping systems had a yielding period more than the moncultured. B. napobrassica intercropping with S. tuberosum in 1∶2 with interval underground part had the best productivity. Intercropping suitable for cultivation in study area.
Langdujing as the main agent produced by Qinghai Academy of Animal and Veterinary Sciences, the Zhankuo 100, Heze, Quick as the organosilicon adjuvants, the different combinations of herbicide were selected to study the control effects and the influence on plant diversity of grassland communities in Jiangxigou County, Qinghai Province where distributed grave Stellera chamaejasme in Kobresiahumilis grassland. The results showed that the amount of Langdujing was the most important factor for control effect and the type and the concentration of organosilicon adjuvants was side effect for control effect which suggested the optimal combination was 675 mLha-1 Langdujing and 112.5 mLha-1 Quick with the control effect of 96.8%. Comparing with the control, the indices of plant diversity decreased in first year and increased in the second year and the structure of plant community tended to better. At the same time, any combination of herbicide was safe for Gramineaess forge.
The present study analyzed the plant biomass, soil physical and chemical properties and soil microbial quantities of different community composition using quadrat sampling method. The results showed the aboveground biomass of Salix paraqplesia alpine shrubs meadow was significantly higher (P0.05) than that of Polygonum macrophyllum meadow, Kobresia tibetica swamp meadow and K. pygmaea meadow, successively. The underground biomass of K. tibetica swamp meadow was significantly higher (P0.05) than that of K. pygmaea meadow, S. paraqplesia shrubs meadow and Potentilla fruticosa meadow, successively. Soil organic matter and soil total nitrogen of K. tibetica swamp meadow were higher than those of P. macrophyllum meadow, S. paraqplesia shrubs meadow and K. pygmaea meadow. On the contrary, the soil microbial quantities of P. macrophyllum meadow which had middle level of soil nutrients contents were largest.
The supercooling points of all stages of Calliptamus italicus and body temperature regulation and the heatresisting ability of adults were measured for the first time in 2013. The results showed that supercooling points of each life stage of C. italicus followed normal distribution. And supercooling points and freezing points of different life stages were different. The wintering eggs had the lowest supercooling point and freezing point (P0.05) while the third instar nymphs had the highest supercooling point (P0.05). There was no significant difference of supercooling point among other instars or between the male and female of the adults. When ambient temperature (Ta) was 41 ℃, LT50 and LT90 of the female and male adults were the longest, which were 623.83, 1 604.98 and 459.52, 1 181.97 h，respectively. Adult body temperature (Tb) and Ta showed a very significant linear relationship (P0.01). When Ta rose by 0.5 ℃min-1, the Tb rise rate was 0.30~0.36 ℃min-1, and the body temperature rise rate of male adults was 0.36 ℃min-1, which was significantly higher than that of its female adults (0.30 ℃min-1).
The relationship between plant secondary metabolites(PSMs) and herbivores is one of the focuses of animal ecology. In this paper, we present three behavioral strategies (avoidance, diet regulation and dietary mixing) used by herbivorous rodents to avoid the negative effects produced by plant secondary metabolites. Avoidance behavior means conditioned learning (animals learn to avoid PSMs on the basis of negative postingestive effects) and food processing before ingestion to avoid the negative effects produced by plant secondary metabolites. Diet regulation focuses mainly on food intake (an herbivore presented with variable PSMs concentrations in its diet should maintain its PSMs dose below its critical threshold by adjusting food intake) and intermeal interval, with which rodents can survival in heterogeneous environment. Dietary mixing leads to greater diversity of ingested phytochemicals that may also lead to mutual toxin neutralization or inactivation, which in turn could reduce susceptibility to plant secondary metabolites.
Based on the survey data of 160 herdsmen from the 9 cities in Inner Mongolia, the present study employed descriptive statistics and ordinal Logistic regression model to do an empirical research on herdsmen' satisfaction degree and the impact factors to the production subsidy policy of grassland ecological compensation and awarding policy. The results showed that the satisfaction degree of the herdsmen to the production subsidy policy was not very high which suggested that the policy still need some improvement. On the other side, the satisfaction degree of the herdsmen was mainly affected by the presence and value of grassland management staff, the amount and the convenience of production subsidies and the effect of subsidies on improving herdsmen income. According to the results of empirical analysis, targeted policy proposals were put forward in the end of the research.
The network virtual teaching training base which included 3 parts of network teaching, network virtual training and exchange area were designed to resolve the problems of traditional education of turfgrass management major involved in teaching venue, equipment, teachers and funding shortage. The system has the functions of teaching information sharing, decision support and query, simulation operations and system management capabilities. With the aid of Campus Network Teaching System platform of Gansu Agricultural University, the system not only achieved the related information resources sharing, but also broke the time and site limitation of practical teaching of turfgrass management. Meanwhile, the system also provided a simple, comprehensive information access and intelligent, professional decisionmaking guidance. Because of informative, fullfeatured and convenience, the system has become a new practical teaching model with important practical significance.