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This paper summarized the importance and the general situation of the nature reserve in China as well as the current issues of grassland nature reserve. Based on the analysis of current situation, three suggestions were proposed as following: declaring the nature reserve of national grassland actively, and strengthening construction and management of the nature reserve, and making nature reserve playing its role sufficiently.
Rangeland management plays important role in soil and vegetation. In order to understand the effects of shallow plowing on degraded alpine meadow, pair-comparison survey was conducted to quantify soil feature and community variation in Damxung county, Tibet Autonomous Region, China. Compared with degraded alpine meadow, soil water content and nutrient increased after 12-year shallow plowing practice with soil water content increased by 35% and bulk soil density decreased by 38.7%. Mineral nitrogen contents of soil increased by 3.2 and 1.7 times at depth of 0―10 cm and 10―20 cm, respectively. Furthermore, shallow plowing practice facilitated vegetation recovery in degraded alpine meadow. Coverage of alpine meadow vegetation significantly increased with the richness and dominance of weeds declined. The species composition changed with dominance of grass in terms of coverage and important value. The above- and under-ground biomass after shallow plowing significantly increased. It indicates that moderate shallow plowing practice can facilitate soil carbon and nitrogen accumulation and vegetation restoration in the degraded alpine meadow. However, it has risk to decrease species richness and community stability.
We analyzed and recorded the herbaceous vegetation of Primary Korean Pine Forest and soil microbial biomass dynamics using ecological community survey methods, chloroform fumigation-extraction, and other methods to study soil physical and chemical properties. The results showed that the dominant herb species in all studied forest types were Athyrium spinulosum and Leymus secalinus. Microbial biomass, carbon, and nitrogen levels decreased with the soil layer deepen. Microbial biomass declined from spring to autumn and increased slightly in winter. Microbial biomass in Primary Korean Pine Forest was higher than that in uniform plantation forests. A significant positive relationship was observed between the dynamics of microbial biomass and soil, soil pH, organic matter content, hydrolyzed nitrogen and available potassium. However, microbial biomass was not significantly correlated with soil water content, soil temperature and available phosphorus.
The characteristics of soil enzyme activities and the relationships between soil enzyme activities and soil nutrients were studied in artificially-established forest on Loess Hilly-Gully region in order to explain the function of artificially-established forest in soil nutrients transformation and fertility status improvement in north of Shaanxi. Three soil enzyme activities of different soil layers in typical artificially-established forest with black locust (Robinia pseudoacacia), Chinese pine (Pinus tabulaeformis), Caragana (Caragana korshinskii) and mixed of Caragana and black locust were studied. Comparing with Caragana pure forest, the activities of soil invertase and alkaline phosphatase increased by 56.81% and 15.89%, respectively, in mixed forest of Caragana and black locust. Geometric mean of three enzyme activities under 31 a black locust were 1.19 and 1.57 times of that under 20 a and 18 a black locust, respectively. Geometric mean of three enzyme activities under 31 a black locust was 1.36 times of that under 30 a Chinese pine. Geometric mean of three enzyme activities in three-year- uncultivated land decreased by 37.89% compared with farm land. There were positive correlations between soil organic carbon, available phosphorus, and available nitrogen and soil invertase, alkaline phosphatase, urease activities, respectively. These results revealed that artificially-established forest was able to significantly improve topsoil enzyme activities.
Plant community and soil microbial characteristics in undegraded, moderate and heavy degraded grasslands were studied. The important value (IM) of Stipa krylovii decreased with grassland degradation, but IM of Artemisia frigida increased. Plant diversity of undegraded and moderate grassland were higher than that of heavy degraded grassland. Total soil nitrogen concentration of heavy degraded grassland was higher than that of undegraded and moderate grasslands, but soil available phosphorus of heavy degraded grassland was the lowest. Soil carbon and nitrogen microbial biomass of undegraded grasslands were higher than degraded grassland. The effects of degradation on arbuscular mycorrhizal fungal spore density and number of bacteria, actinomyces and fungi depended on seasonal dynamics. Number of fungi in undegraded grassland was higher than heavy degraded grassland from May to August, but there was no significant difference between these two types of grassland in September. Number of bacteria in undegraded grassland was higher than heavy degraded grassland from July to September, but there was no significant difference between these two types of grassland in June. Total soil nitrogen concentration, soil available phosphorus, and number of microorganism were highest in July or August. There was significant linear correlation between number of bacteria, actinomyces or fungi and total soil nitrogen or microbial biomass nitrogen. There was significant linear correlation between Number of bacteria and actinomyces and microbial biomass carbon.
In order to understand the impacts of yak dung on greenhouse gas (GHG) emission in the alpine meadow of the Qinghai-Tibetan Plateau during the growing season, nitrous oxide(N2O), methane(CH4), and carbon oxide(CO2) fluxes in Kobresia-dominanted meadow were measured by the static opaque chamber-gas chromatograph method. The results showed that the application of dung had distinct stimulating effects for N2O, CH4, and CO2 fluxes, which occurred during the 1-50 days after application although the peak value presented at different time. The global warming potential induced by GHG emissions after dung application increased by 39.2%. The global warming potential and the cumulative flux of N2O, CH4, and CO2 during three months research period after dung application was 2 102, 0.095, 0.412 and 2 064 g·m-2, respectively. Emission-time pattern of greenhouse gas should be paid more attention to assess global change to animals’ excrements as yak dung patches were strong GHG source.
Endophytic cellulose-decomposing bacteria were isolated from Kobreasia capillifolia which is dominant grass on alpine grassland in the Eastern Qilian Mountains. All of the isolated bacteria strains were screened and identified. At the same time, the conditions of producing cellulose were optimized by orthogonal test. Totally, there were 6 endophytic bacteria strains isolated from K.capillifolia and only two of them ——X5 and X6 can decompose cellulose. Only strain X5 were further analysis as its potential cellulase enzymatic activity which was 0.456 U. And the ratio of the diameter between lysis zone and colony diameter of strain X5 was up to 10.45. The optimum culture conditions for producing cellulose were 5 g·L-1 peptone, 5 g·L-1 yeast powder, 5 g·L-1 sodium carboxymethylcellulose, pH 8.5 and 20 ℃ culture temperature . Cellulase enzymatic activity of strain X5 was 0.862 U after optimization, which was the 1.89 times of that before optimization. Strain X5 was Rod-shaped with a size of (0.66~0.92) μm×(1.67~2.43) μm, Gram-positive, and can produce spores. Based on these physiological and biochemical characteristics and 16S rDNA gene sequence analysis, X5 were identified as Bacillus sphaericus.
In the present study, we analyzed the seasonal changes of fractional vegetation cover (FVC) of alpine grassland during the whole growing season and discussed the efficiency of remote sensing retrieval using Chinese environmental satellite (HJ-1A/1B) images and field data. The results showed that the distribution of FVC presented a reversed “U” curve with fluctuations in the middle during the whole growing season; There were good linear correlation between the measured FVC and normalized difference vegetation index (NDVI) calculated from HJ image in growing season. The slopes of fitted linear models performed as parabolic curve with the vertex as the theoretical peak of growing season. In addition, compared with single maximum value composites (MVC) and single-day methods, the inversion of double MVC method was the most accurate and closed to the “True” value. The inversion results of single MVC method and double MVC method had similar trend, however, the former was significant underestimation. The single-day method did not appear the same trend with a little underestimation compared with single MVC method.
Based on the MODIS land cover data sets, we studied the impacts of human activities on distribution of grassland, cropland and the potential natural vegetation (PNV) in China. The results showed that the cropland area dropped from 1.445×108 ha in 2001 to 1.425×108 ha in 2009. The maximum area——1.543×108 ha was in 2005 and the minimum area ——1.363×108 ha was in 2008. The grassland area decreased from 4.201×108 ha in 2003 to 4.032×108 ha in 2009 during the research period. In total, the decreasing rate of cropland area (13.49%) was greater than that of grassland (3.29%). The rate which grassland converted to arable land decreased by 4.96% per year, however, the rate converted to other land cover types increased by 20.87% per year. The rates of which cropland converted to grassland and other land cover types were similar. The rates of other land cover types converted into grassland (15.43%) and cropland(2.45%) decreased gradually year by year. The intensity of human occupancy of PNV increased during this research period which was relatively more intensive for grassland (38.18%) and forest (37.36%) among PNV categories.
Based on quantitative reports and literatures about effectiveness assessment of nature reserves and the status indicators from DPSIR model, 15 key indicators assigned to 5 criteria were selected as the indicator system to evaluate the ecological effects of grassland nature reservation. The present study also analyzed the corresponding quantitative parameters of the indicator about protected objectives, ecological function and environmental factors according to the relevant regulations and standards and academic authorities. These indicators can be selected to assess subjects and goals, evaluation cycle as well as existing data in practice. Therefore, these indices possible represented the ecological effects of grassland nature reserves.
Full-length cDNA Library for leaves of Vicia unijuga was constructed with SMARTTM cDNA library construction kit after total RNA of V.unijuga leaves was extracted by Trizol reagent. The primary library has titer of 2.3×106 pfu·mL-1, while the amplified library has a high titer of 6.2×109 pfu·mL-1 and 92.7％ recombinant rate. Sixteen plaques were randomly selected from the amplified library and amplified by PCR. The results showed that the inserted fragment length ranged from 500 to 2 500 bp. The 3′end full-length cDNA of CAD, a Vicia unijuga gene related with lignin synthesis which has been cloned by RACE, was amplified in this cDNA library using PCR, which indicated that the cDNA library for leaves of V.unijuga had been successfully constructed using SMART technique.
In order to establish the tissue culture and rapid propagation system of Polygonum viscosum, the present study explored the impacts of different concentrations of hormone on axillary buds induction, axillary buds proliferation and root induction with the stems with axillary buds of P.m viscosum as explant and MS as the basic medium. The results showed that the optimal medium for axillary bud induction was MS medium with 2.0 mg·L-1 6-BA purine and 0.1 mg·L-1 NAA which had the highest induction rate (88.89%). The optimal medium for axillary buds proliferation was MS medium with 2.0 mg·L-1 6-BA, 0.3 mg·L-1 NAA acid and 0.5 mg·L-1 KT which had the highest coefficient of multiplication (5.17). The optimal medium for root induction was 1/2 MS medium with 0.7 mg·L-1 NAA which had the highest root induction rate (98.89%).Plants grew very well after transplanting with the survival rate of 93.33%.This research supplied favorable information for P.viscosum rapid propagation and genetic engineering.
It has been noticed that the plants in the alpine region should adopt different reproductive strategies to ensure the successful female reproduction. The variations of female fitness components of intra-inflorescence were investigated in different branch positions in the perennial hermaphrodite herb Anemone rivularis var. flore-minore from the Qinghai-Tibet Plateau. The results showed that ovule number per flower and mean seed weight per fruit varied with the flowers’ open order from the first branch to the third branch in different habitats. The seed number per fruit at the second branch was highest, while single seed weight per fruit significantly decreased (P＜0.001) from the first branch to the third branch. The seed-setting rate and female allocation did not depend on inflorescence branch part, whereas there were significantly positive correlations between female fitness components.
Daily variation of photosynthetic characteristics and light-photosynthetic rate response curve of Carex leucochlora were analyzed using Licor-6400 portable photosynthesis system in May, August and October. The results showed that the daily variation of net photosynthetic rate, transpiration rate and stomatal conductance in leaves presented two-peak curve and midday depression in May and presented single-peak curve in both August and October. Photosynthetic characteristics were extensively affected by environmental conditions of different months. The maximal net photosynthetic rate had closer correlation with soil moisture and air temperature. The lower transpiration rate and stomatal conductance and higher water utilization efficiency indicated that C.leucochlora was a drought-resistant plant species. Net photosynthetic rate of C.leucochlora was low in different months. Light compensation points were less than 20 μmol·m-2·s-1, light saturation points were less than 1 000 μmol·m-2·s-1 in May and August. Light compensation points were 30 μmol·m-2·s-1 and light saturation points were 1 047 μmol·m-2·s-1 in October which indicated that C.leucochlora was a typical shade-tolerance plant.
In order to select promising germplasm resource, the present study evaluated some agronomic traits and production performance of 6 Elymus germplasm from different altitudes of Tibetan Plateau. The results showed that different germplasm had different performance. Leaves and panicle of E.nutans from Guinan County had outstanding performance with higher seed yield (1 265.9 kg·ha-1), which had potential to be forage with seeds production. E.nutans from Gonghe County with high forage yield (8 714.9 kg·ha-1)and the strongest stability had potential to be long-term forage breeding material. E.sibiricus from Dari County with longest growing period(170 d), highest seed yield(1 431.3 kg·ha-1) and higher forage yield(5 780.9 kg·ha-1) had potential to bred as medium- or long-term forage and seed production. E.sibiricus from Gangcha County also had potential to be forage with seeds production because their leaves and panicle had outstanding performance and their forage yield was higher (6 297.4 kg·ha-1). E.sibiricus from Banma County and Qinghai Lake around area had potential to be precocious forage resources because of their shortest growing days (120 d) and poor production performance.
Three grazing intensities were applied on Zhaosu Army-Horse Farm to compare variations of aboveground biomass and nutrient contents of plant community from 2011 to 2012. The results showed that aboveground biomass decreased under each treatment with extension of grazing time. For aboveground biomass, there were significant differences between different grazing treatments and the control area with the extension of grazing time in every year (P＜0.05). The crude protein contents of Thymus asiaticus, Medicago falcate, Carex liparocarpos, Stipa capillata and Festuca ovina decreased with the extension of grazing time, whereas there was no significant difference among different treatments. The dry matter contents of these 5 dominant species decreased and then slightly increased followed by further decrease during the whole grazing period although the fluctuation rate was 0.01%～2.00%. The neutral detergent fiber and the acid detergent fiber of these 5 dominant species increased with slightly decreased in the middle of grazing time. These observed variation of aboveground biomass and nutrient content showed that moderate grazing had less influence which was better for sustainable development of grassland. The effects of different grazing intensity on aboveground biomass and nutrient were far less than the effects of Inter-annual climate change.
The distribution of grassland biomass and impact factors in north slope of Tianshan were analyzed in this study. The biomass of different types of grassland was estimated to reveal the spatial distribution of aboveground and underground biomass and the relationship between biomass and environmental factors. The results showed that grassland biomass decreased in the order of temperate mountain meadowtemperate meadow steppealpine meadowlow saline meadowtemperate steppetemperate desert steppetemperate steppe deserttemperate desert. There was no significant variation for spatial distribution of aboveground and underground biomass within the same grassland. The aboveground biomass of lowland saline meadow was significantly higher (P0.05) than that in other types of grassland. For underground biomass and total biomass, there was significant difference between temperate mountain meadow and other types of grassland (P0.05). The root-shoot ratios of each type of grassland were mainly between 3.2 and 20.0. The aboveground biomass was correlated with annual precipitation and the extent of human using, however, the underground biomass correlated with annual precipitation, annual average temperature and landform.
In order to understand resources allocation pattern of Seriphidium transiliense under grazing condition, the content and storage allocation of carbon, nitrogen, phosphorus and potassium of roots, stems, leaves and flowers (or seeds) were measured. The results showed that the phosphorus content of roots, the nitrogen, phosphorus, potassium and carbon content of flowers or seeds decreased under grazing condition and the other nutrition content changed complicatedly without regular pattern. It proved that grazing contribute to potassium and carbon accumulation allocation of S.transiliense. The rates of potassium and carbon accumulation allocation in roots increased by 3.16%～12.79% and 2.12%～12.74%, respectively. The rates of potassium accumulation allocation decreased in stems, leaves and flowers (seeds) by 1.67%～14.13%, 1.49%～2.89% and 0.33%～0.41%, respectively. The rates of the carbon reserve allocation decreased in stems, leaves and flowers (seeds) by 6.45%～11.37%, 0.77%～4.18% and 0.01%～0.09%, respectively. During vegetative period and flowering stage, the nitrogen accumulation allocation of S.transiliense in root increased by 11.91%～18.45% and that in leaves and flowers (seeds) decreased by 8%～14.58% and 1.78%～4.76%, respectively. The phosphorus accumulation allocation had no relationship with grazing.
Trifolium repens, Lolium perenne, and Astragalus sinicus were planted in fallow field after harvesting ramie(Boehmeria nivea) in winter to study the impacts of interplanting grass on the density, biological diversity and dominant species of weeds. One year after planting L.perenne, T.repens and A.sinicus, the overall densities of weeds were 59.2, 107.7 and 128.2 plant·m-2 and declined by 73.35%, 51.53% and 42.30% compared with control, respectively. The biomass of weeds were 62.33, 142.1 and 112.86 g·m-2 and declined by 78.11%, 50.31%, 60.53%, respectively. These results revealed that interplanting grass with these three cold-season grasses can reduce the hazard of weeds in ramie field and L.perenne were most effective. These three cold-season grasses did not remarkably change the categories of predominant weeds although Simpson evenness index and Shannon-Winner diversity index decreased a little bit. The biological diversity index of weeds after planting A.sinicus was slightly higher than that after planting T.repens and L.perenne.
The orthogonal experimental was designed to screen the best fertilizer combination and recommend fertilizer rate of nitrogen, phosphorus, potassium fertilizer for alfalfa in Beijing area. The results showed that the forage yield, growth rate and regeneration rate of alfalfa significantly increased using nitrogen, phosphorus and potassium fertilizers in the areas with shortage of nitrogen and phosphorus fertilizers. The growth rate and regeneration rate of alfalfa with fertilization treatments were significantly higher than that without fertilization treatment (P0.05). The forage yield increased by 17.31% to 29.28% which showed the significant effects of fertilization. The fertilization combination with the highest yield increase rate as N 50 kg·ha-1＋P 140 kg·ha-1＋K 160 kg·ha-1. However, the orthogonal analysis results showed that the fertilization combination with the highest yield increase rate was N 100 kg·ha-1＋P 140 kg·ha-1＋K 160 kg·ha-1. After comprehensive analysis, the recommendation fertilizer rate was N 50～100 kg·ha-1, P 140 kg·ha-1 K, and 160 kg·ha-1 which had the highest forage yield of alfalfa on those areas with shortage of nitrogen and phosphorus fertilizers.
With the rapid development of the grassland industry in China and the increasing demands for grass seeds, the improving of quality and yield of grass seeds have become bottleneck during grass industry development. It is much important to lucubrate the rules of the grass seeds’ dormancy and germination which is one of the premises for quality and yield of grass seed improvement and grassland industry development. Hormone is one of the key factor for regulating seeds’ dormancy and germination which is always a hot topic in seed physiology and biochemistry studies. This paper explore the hormone roles in grass seeds’ dormancy and germination to further analysis the interaction and physiological mechanism of different hormones and grass seeds’ dormancy and germination.
In angiosperms, a serious of recognition events are involved in pollen-pistil interactions since pollen grains landed on the stigma. Such interaction processes include recognition between pollen and stigma, hydration and germination of pollen grains, pollen tube growth and guidance, sperm release and double fertilization in the embryo sac. In recent years, the genes involved in process of pollen-pistil interactions, pollen tube growth and guidance have been discovered and cloned. In this paper, the advances of adhesion of pollen grains and their hydration, germination and growth have been reviewed. In particular, the machanisms of chemical compounds, such as glycoproteins interactions in pollen adhesion, lipid regulation pathway in pollen hydration and arabinogalactan proteins in polar growth of pollen tube, have been discussed to provide theoretical basis for the reproductive biology in angiosperms.
After analysis the issues of rodent control of the natural grassland in China, this study proposed the strategic positions and goals of rodent control of the natural grassland in China, and proposed the suggestions of rodent control of the natural grassland in China as following. The first one is to quantify the density for causing disaster and disaster classes; the second one is to control rodent density though rational graze, introduction or simulation of natural enemy, and use of co-evolution mechanism of different composition of ecosystem; The third one is to construct the early warning system for rodent control of the natural grassland in China; The fourth is to make emergency program and standard of rodent control of the natural grassland in China.
In current study, seven Shaanbei white cashmere goats with the same age and similar weight were separately fitted with rumen fistula (3 goats) or with T-type duodenal fistula (4 goats). Both the mobile nylon bag method and the three step in vitro procedure were employed to evaluate the apparent small intestinal digestibility of 8 feedstuffs, respectively. The apparent small intestinal digestibility of 8 feedstuffs (cotton meal, rape seed dregs, corn gluten meal, yeast, mulbrrry leaves, reed, amorpha, caragana) measured by mobile nylon bag was 77.24%、60.08%、96.36%、18.49%、42.05%、49.62%、30.36%、52.21%, respectively. Furthermore, regression analysis showed that there was positive correlation between the mobile nylon bag method and the three step in-vitro procedure which produced the equation of y=0.802 3x-0.128 5 (R2=0.911 5). In conclusion, cornglutenmeal has the potential capability to provid higher rumen undegraded protein (RUP).
The present study analyzed the community compositions, diversities and similarities of 4 types of grassland. There were total 39 species of grasshoppers obtained in this study. There were 10 species of grasshoppers which could lead to economic losses and constituted the dominant populations of grasshopper in natural grassland of Ningxia. The numbers of individuals and species, diversity, and species richness of grasshoppers were different in these different types of grassland. The number of species of grasshoppers was highest in the desert steppe region and lowest in the meadow area. The numbers of individuals of grasshoppers were highest in dry rangeland area and lowest in meadow area. The diversity of grasshoppers was highest in desert steppe region and lowest in dry rangeland area. The species richness of grasshoppers was highest in desert steppe region and lowest in the meadow area. The similarities of grasshopper groups were highest in desert steppe region and desert-grassland area with the value of 0.655, followed by meadow area and dry rangeland area with the value of 0.578. The order of similarities of grasshoppers was: desert steppe region and dry rangeland area, desert-grassland area and dry rangeland area, desert steppe region and meadow area, desert-grassland area and meadow area with the similarity index of 0.517, 0.405, 0.423, 0.324, respectively.
The present paper discussed the role of traditional ecological education culture in Mongolian nomadic civilization on conservation and sustainable utilization of rangeland resources with the ethnoecological principles combined with ecological survey and interviews and literature studies. Few conclusions have been drew as following: 1) Mongolian summarized the importance of conservation of sandy vegetation and the principle of selecting different species on sand-fixing and wind-preventing according to the geomorphological characteristics and phynological regulations by the form of folk songs, proverbs and sayings. 2) These folk songs, proverbs and sayings are effective and correct way of Mongolian ecological education which is different with traditional practice, religious and legal education culture. 3) The abundant ecological ideas contained in folk songs, proverbs and sayings play an important role for adolescent to deepen and enhance their knowledge of fragile rangeland ecosystem and avoiding unreasonable measures for the management of rangeland and sand-fixing and wind-preventing. These ecological education cultures are becoming the natural strength and management mechanisms which are very effective in sustainable conservation of rangeland ecosystem and provide valuable experiences for ecological civilization construction of the northern steppe zone and desert zone in China.
Based on the theoretical frame and evaluation index system on assessment of comprehensive benefit of grassland construction engineering project, a case study was conduced in Gannan Tibet Municipality, including Maqu County, Luqu County, Xiahe County and Hezuo City. Gannan Tibet Municipality is one of districts that the recovery and construction projects of Gansu natural grassland were implemented. In this study, 51 assessment indexes were selected, according to the actual conditions of Gannan. Besides, a hierarchy structure and comprehensive assessment model was designed. The total weight of every index was calculated based on the analytic hierarchy process (AHP). The results showed that, the ecological, economic and social benefits were significantly increased with the conducing of projects, and which were increased by 6.135%, 5.433% and 14.042%, respectively. Compared with the corresponding values, which were before the implementation of recovery and construction projects, the landscape benefit was maintained, the starts quo and the environmental benefit decreased from 0.105 to 0.103.
In order to provide more technology support for restoring the degraded ‘bare soil land’ meadow on Qinghai-Tibetan plateau, the present study analyzed the aboveground biomass, underground biomass, height of community of monoculture Festuca sinensis pasture and mixture pasture of F.sinensis＋Poa crymophila＋Elymus nutans which built on ‘bare soil land’ degraded meadow. The results showed that both of these two kinds of pasture presented good productivity under appropriate management. However, the mixture pasture presented higher productivity and better community characteristics than monoculture F.sinensis pasture. The mixture pasture could accumulate more root biomass to support aboveground vegetation. These results revealed that F.sinensis was the best forage for restoring the degraded ‘bare soil land’ if mixcultured with other grasses. At the same time, the recognition of local herders to establish pasture should be improved because it was critical to develop pasture establishing technology on Qinghai-Tibetan plateau, especially for restoring the ‘bare soil land’ degraded meadow.