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The remoter sensor from TG-1 platform can provide the hyperspectral and high-resolution images. In the present study, the snow cover fraction and snow size were retrieved from domestic hyperspectral short-wave infrared (SWI) data at Heihe upstream on Qilian Mountains to test its application in the civilian area. A new algorithm that combined Vertex Component Analysis (VCA) component automatic extraction techniques with sparse regression pixels unmixed techniques were developed and to produce snow cover fraction map. The results were verified using the higher spatial resolution images that also been achieved by TG-1 platform. Initial analysis indicated the root mean square error(RMSE) and the correlation coefficient of both validate area was 0.24 and 0.27, 0.72 and 0.84 compared with reference images, respectively. In addition, the ART radiative transfer theory referred to snow particle shape have been approved by the optimizing the shaper factor and retrieval band. The improved algorithm then provided the snow grain size map by domestic hyperspectral data. The maps were validated indirectly by hyperion data which covered the similar field area. The results showed that the domestic hyperspectral data were appropriate to produce SFC and snow grain size map and were feasible to hydrological and climate models.
In the present study, the normalized difference vegetation index (NDVI) estimated from MODIS data were employed to analyze the temporal and spatial dynamic of different grassland types during growth season (April to October) in the recent 10 years (from 2003 to 2012) in Xilingol. The NDVI decreased from northeast to southwest in Xilingol in spatial. The maximum spatial differences occurred in 2005 and the minimum spatial differences occurred in 2007. The spatial variation of the same grassland type was similar during the study period. Temporal series analysis showed that the whole regional NDVI in 2012 was the maximum which followed by 2003. However, the minimum regional NDVI variations occurred in different period for different grasslands. For example, sandy grassland and desert steppe had minimum regional NDVI in 2005 and major NDVI fluctuations from 2004 to 2006, however, meadow steppe and typical steppe had minimum regional NDVI in 2007 and major NDVI fluctuations from 2007 to 2009. Spatial variation analysis showed the coefficient of variation (CV) of sandy grassland from 2003 to 2012 was less than 0.1 which indicated this type grassland was very stabilization. The CV of meadow steppe, typical steppe and desert steppe gradually increase which also was stable at 0.1 to 0.2. These results indicated that the ecological vulnerability of Xilingol was stabilization. The correlation analysis between main meteorological elements and NDVI indicated that there was a significant positive correlation between NDVI and precipitation which has a coefficient of 0.83. However, there was negative correlation between sunshine period and NDVI and no significant relationship between average temperature and NDVI.
Effects of stand density on soil physical and chemical properties were studied in eight semi-natural mixed larch-spruce-fir stands. The results showed that soil physical properties were significantly different at different soil depth in the same stand density. Except with soil total nitrogen, there was no significant difference for other nutrient concentrations between soil depths. Soil nutrient concentrations did not have significant change rule at different stand densities and declining trend in a certain density. At the density of 1 058 trees·hm-2, soil nutrient concentrations decreased but without significant difference which showed that soil nutrients were not affected by current stand densities in the experimental area. Replanting may be appropriate to increase the use efficiency of forestland.
The Biolog-ECO microplate method was employed to study vegetation characteristics and carbon source utilization of soil microorganism community in rhizosphere of Leymus chinensis under three grazing intensity (without grazing, light grazing and heavy grazing) in short period. The results showed that there were difference in the carbon source utilization of soil microorganism community in rhizosphere of L.chinensis under three grazing intensities. Light grazing can promote the growth of herbage and had the highest metabolic activity. The treatment of without grazing had the lowest metabolic activity and more microorganisms using polymers. In the matter of diversity index, the treatment of without grazing had the highest diversity index which were lower and the treatments of both light grazing and heavy grazing were similar. Principle component analysis showed that the principal carbon source of soil microorganism of light grazing and heavy grazing treatments were carbohydrate, amino acid and polymer, respectively. There was less carbon source of soil microorganism for without grazing treatment. The soil physicochemical property had important impacts on soil microorganism under different grazing intensities.
To determine the relationship between the rhizosphere soil and AM (Arbuscular Mycorrhizal) fungi in Songnen saline-alkaline grassland, twenty six species in eleven families from Songnen saline-alkaline grassland were gathered and the colonization of AM fungi together with the physicochemical properties of rhizosphere were analyzed in July, 2013. The results showed that all the plant species were colonized by AM fungi, among which Taraxacum mongolicum got the highest colonization rate of 79.25%, while Polygonum aviculare got the lowest colonization rate of only 3.37%. Meanwhile, significant positive correlations were found between organic matter content and total nitrogen content of rhizosphere soil and the mycorrhizal colonization rate, colonization intensity, vesicle abundance and arbuscule abundance of AM fungi (P0.01); whereas significant negative correlations were shown between pH value and total salt content of the soil and the vesicle abundance of AM fungi (P0.05), with the correlation coefficient were －0.729 and －0.449, respectively. These experimental results indicated that the organic matter contents and total nitrogen contents of soil had a significant influence on the forming of AM fungi, whereas pH value and total salt content only had a certain influence on vesicle abundance.
Through the field investigation and laboratory analysis, the carbon storage of Qinghai spruce(Picea crassifolia)in Ningxia Helan Nature Reserve were studied. The results showed that Qinghai spruce(Picea crassifolia)forest was the important forest carbon pool in Ningxia Helan mountain where there were organic carbon storage of 24.771, 5.96, 0.491 and 18.32 kg·m-2 for total, the wood, the ground layer and the soil layer, respectively. These results showed that the soil organic carbon storage was the main organic carbon pool in Helan Qinghai spruce forest which accounted for 73.96% of the total organic carbon reserves.
In order to improve vigorous growth, increase the amount of blossom and flower diameter and extend blooming period of Rosa chinensis, different organic fertilizers such as sheep manure, rotten human waste, KOMIX humus acid were used to study the effects of organic fertilizers on growing and florescence of climbing rose. The results showed that plants with organic fertilizers possessed better growth and luxuriant foliage. The best organic fertilizers was KOMIX humic acid which promoted plant budding and flowering early, bigger flowers, longer blooming season, richer colors, and clean and pollution-free soil. With KOMIX humic acid treatment, the average plant height, flower amount per plant, flower diameter and branch number of these 4 varieties were significantly higher than the other treatments (P0.05). Average plant height, flower diameter and branch number of 4 varieties were significantly higher than the other controls, and its dry matter ratio was 16%, greatly improve the ornamental value of climbing rose.
This experiment studied the impacts of the mixed sowing proportion of Kentucky bluegrass, perennial ryegrass and red fescue on turf quality in field conditions in order to provide practical basis for the mixed sowing of these 3 turf grasses in the northern area of China. The results showed the turf with the lower proportion of Kentucky bluegrass or the higher proportion of red fescue fixed with 20% of perennial ryegrass, had greater density, better texture, more green, smaller underground biomass.The optimal mixed sowing ratio of these three cool-season turfgrasses was Kentucky bluegrass:perennial ryegrass:red fescue=1:2:7 after comprehensive analysis all of the turf quality indices.
With the 3 factors (rooting rate, average root length and average root quantity) as the indicators of rooting qualities, we conducted a study on the optimization of asexual cutting propagation techniques for Rubus alceaefolius with orthogonal experimental design. The results showed that the rooting qualities of R.alceaefolius after cutting propagation significantly affected by NAA concentration, propagation matrix, cuttings type and processing time. Propagation matrix had the greatest impacts on the rooting qualities, processing time had the second greatest impacts and NAA concentration and cutting type had the lower impacts. Under the treatment with 100 mg·L-1 NAA concentration, 2 hours processing time, garden soil as the propagation matrix, and annual stems with buds as the cuttings, the rooting quality of R.alceaefolius were the best.
Heavy metal contamination of the land surface and groundwater due to increased industrialization and geochemical activities is a serious environmental problem. Plants can improve phytoremediation by endophyte fungi to enhance the tolerance to heavy metal stress. The present paper summarized the research progress of the improved tolerance of the grasses to the heavy metal stress from the following aspects which included the effects of heavy metals on grasses consist of germination rates, total biomass and root activity, response of physiology and biochemistry of grasses to heavy metal stress and resistance or tolerance mechanisms of the endophyte to improve the resistance to the heavy metal stress comprised antioxidant enzymes, antioxidant materials, heavy metal chelate and phytoremediation. This review put forward a new method for heavy metal tolerance and better phytoremediation breeding by endophyte.
According to the restriction enzyme sites of plant expression vector and sequence of CsLEA gene from Cleistogenes songorica, over expression vector was recombined by inserting the open reading frame (ORF) sequence to pBI121, and the antisense plant expression vector was constructed by ligating 480 bp sequence of CsLEA gene to pBI121 in the antisense orientation. Moreover, the recombined plasmid was transformed into Agrobacterium tumefaciens GV3101 by electroporation method. Using pollen-tube pathway, the plasmid was transformed into Arabidopsis thaliana and T1 positive plants were obtained by kanamycin resistance selection and PCR confirmation.
The light green loose callus of Androsace longifolia were selected as the basic experimental materials. The effects of different hormones, sucrose concentrations, and shaker speeds on the cell dry weight on cell suspension cultures were compared. The results showed that the optimal hormone of A.longifolia suspension culture was 6-BA which had cell dry weight of 0.15 g with optimal concentration of 0.3 mg·L-1. Cell dry weight was higher when the inoculation amount of the callus was 1 g. The optimal sucrose concentration and shaker speed was 2% and 105 r·min-1, respectively. During the culturing process, the pH value decreased and then gradually increased and stabilized at the day 21 of culture. Conductivity of the culture solution declined and then increased with the increase of cell number which was lowest after 15 days culture. The optimal harvest time of the cell suspension cultures was 12 days after culturing based on the cell dry weights.
Effects of drought stress simulated by polyethylene glycol (PEG-6000) on Glycyrrhiza uralensis seed germination and seeding growth were analyzed. The results showed that the pretreatment of concentrated sulfuric acid significantly improved the germination rate. PEG stress delayed the germination of G.uralensis seeds. The vigor index of seeds with 5%~10% of PEG concentration treatment was higher than that of control treatment, however, the seed germination were inhibited significantly (P0.05) with higher PEG concentration treatments. PEG stress improved the root length of G.uralensis. For the aboveground part, the lower concentration of PEG had promoting effects while higher concentration of PEG had significantly inhibiting effects. There is significantly negative correlation between PEG concentration and GR(Germination Rate), GP(Germination Potential), GI(Germination Index) and the relation models between PEG concentration and GR, GI were established.
Hard seeds of wild Astragalus kifonsanicus seriously affected seed germination. In the present experiment, A. kifonsanicus seeds were treated with three different methods including breaking seed coats, sulfuric acid and sodium hydroxide soaking. The results showed that breaking seed coats significantly increased seed germination rate (P0.01) which was 99% and increased by 13 times compared with controls. The germination energy and vigor index of seed, which were 64.67% and 10.48, increased by 31 and 27 times compared with controls, respectively. After being soaking in 98% sulfuric acid for 10 min, the germination rate, germination energy and vigor index of A.kifonsanicus were 83%, 67.33% and 6.51, which increased by 13, 34 and 17 times compared with controls, respectively. In addition, sodium hydroxide soaking did not have significant effects on seed germination of A.kifonsanicus. The present study provided theoretical basis for large scale cultivation and utilization and fast sowing in the field.
Aluminum tolerance of Chrysopogon aciculatus had been evaluated in different aluminum concentrations by leaf color, turf quality and leaf firing percentage to screen critical aluminum concentration with water culture method. The result showed that there were significant (P0.05) differences between different treatments of aluminum concentrations. With the increase of aluminum concentration (0~2.7 mmol·L-1), the leaf firing percentage increased, while the scores of leaf color and turf quality decreased. Fifty percentage of leaf firing percentage can be survival index according to regression equation and the lethal aluminum concentration of C.aciculatus was 1.909 6 mmol·L-1.
The tuber biomass, tuber number and root biomass which distributed in different root regions of Helianthus tuberosus were tested to explore the distribution of roots and tubers in extreme sparse field conditions. The results showed that the tuber density, root density and number of tubers per unit area decreased with the increasing distance to root centre. The maximum value of all these three indices appeared in the region which the distance to root centre was less than 10 cm. The relationship between tuber density, root density or number of tubers per unit area and the distance to root centre all performed as power function models. The functions were y=160.5x-1.24(R2=0.995), y=817.8x-1.71(R2=0.813)和y=542.7x-0.81(R2=0.917), respectively. However, the tuber biomass production increased firstly and then decreased with the increasing distance to root centre. The maximum value appeared in the region which the distance to root centre was 40-50 cm. Hopefully, the present study can provide more reference information for H.tuberosus cultivation management.
The influence of different light intensities(100%, 42.5% and 12.5%)on carbon-nitrogen metabolism of Catharanthus roseus leaves was studied by measured the contents of C-N compounds and the activities of related enzymes. With the decrease of light intensity, the contents of starch and soluble sugar dropped while the contents of soluble protein, free amino acid and nitrate increased. The difference of enzymes activities involved in carbon and nitrogen metabolism under different light intensity were significant (P0.05). With the decrease of light intensity, the activities of amylase, sucrose phosphate synthase (SPS), nitrate reductase (NR) and glutamine synthase (GS) decreased while the activity of sucrose synthase (SS) increased.With the decrease of light intensity, total flavonoid contents decreased, contents and yield of vinblastine and vincristine showed a tendency of increase after decrease while contents and yield of vindoline and atharanthine always increased.
The present study analyzed the effects of nitrate nitrogen (NO3--N)on mulberry seedlings growth and photosynthetic characteristics under the alkaline salts (Na2CO3) stress by using solution culture method. Under Na2CO3 stress, stomatal limitation of mulberry seedlings decreased with the increase of NO3--N which improved utilization of carbon dioxide in mesophyll cells in leaves, significantly reduced damages of salt stress on mulberry seedlings, and promoted accumulation of shoot and root biomass. The NO3--N improved actual photochemical efficiency (ФPSⅡ) and electron transfer rate (ETR) of mulberry seedlings, alleviated reduction of PSⅡphotochemical efficiency (Fv/Fm), and reduced the photo inhibition degree of mulberry seedlings leaves under Na2CO3 stress. The increase in NO3--N also reduced the proportion of invalid forms of heat energy dissipation in mulberry seedling leaves under Na2CO3 stress which was useful for leaves to absorbe more lights for photochemical reaction. The synergy between the heat dissipation and xanthophyll cycle effectively protected the normal physiological function of PSⅡ and improved light utilization capacity of the leaves. The NO3--N concentration of 12.5 mmol·L-1 treatment was greater than other concentrations. Therefore, the increase in NO3--N can improve leaves light use efficiency and biomass of mulberry seedling under Na2CO3 stress.
The soil physical and chemical properties of 0－20 cm soil lay in mix-sown pasture which has been constructed 3 years by six different kinds of Legumionosae and Gramineae herbage (Vicia tenuifolia, Medicago sativa, Onobrychis viciaefolia, Phleum pretense, Agropyron cristatum, Dactylis glomerata) were studied. The mix-sowed type numbers were 3, 4, 5, 6 and proportion of Legumionosae and Gramineae was 4∶6. The results showed that all mix-sown combinations had different impacts on soil physical and chemical properties comparing with CK. The water content in 0－10 cm soil, bulk density of T1 (V.tenuifolia+M.sativa+O.viciaefolia+P.pretense+A.cristatum+D.glomerata) and T3 (V.tenuifolia+O.viciaefolia+P.pretense+A.cristatum+D.glomerata) were significant higher (P0.05) than that of the control. In 0－20 cm layer, the soil organic matter, available nitrogen, available phosphorus, available potassium of T1 and T3 were significant higher than that of other mix-sown combinations and control (P0.05). The results indicated T1 and T3 treatment were more beneficial for maintaining grassland soil stability and suitable for local and similar habitat conditions.
The natural restoration process of plant community in Grave-Soil-Taken Field which formed by road construction at different stages in the alpine steppe of Tongde county in the Three-River Source Region was studied in the present research. The combined community field survey and soil analysis were employed to investigate the natural succession of alpine steppe vegetation of Grave-Soil-Taken Field. The results showed that total above-ground biomass increased with restoration time. However, the total aboveground biomass of plant community in Grave-Soil-Taken Field had no significant difference with the control plots after 30 years of vegetation recovery. The total underground biomass in Grave-Soil-Taken Field fluctuated between 5 years and 30 years after road construction. Furthermore, the total underground biomass was significantly lower (P0.05) than that of control after 30 of vegetation recovery. Species diversity significantly increased (P0.05) between 5 years and 30 years after road construction. Comprehensive recovery capacity of alpine steppe decreased with recovery time increasing. The stability of plant communities increased with recovery time increasing. After 30 years of natural restoration, the plant communities were relatively stable. Changes of soil nutrients, especially organic mass and available phosphorus had significant influence on the productivity of plant community, species diversity and comprehensive recovery capacity.
Phosphorus is one of the most important mineral nutrients. It is essential for plant growth and development involved in various biochemical processes, such as lipid metabolism and the biosynthesis of nucleic acids and cell membranes. However, low soil available phosphorus content has become a limited factor to the growth of legume. Long-term phosphorus deficiency stress promoted legume’s adaptations and evolution in their mechanisms of morphological, physiological, molecular biological and so on. Understanding these adaptive mechanisms developed by legume will play a critical role in agronomic practices optimization, resource conservation and environmental protection as well as the development of biotechnological strategies which aim to improve the availability of phosphorus for legume. Legume adaptations to low phosphorus stress environment and efficient absorption limited effective phosphorus in soil have become research focus in the current. In the present study, progresses and problems in aspects of adaptation mechanisms on root morphological, physiological, biochemical and molecular biological under phosphorus deficiency stress were reviewed to provide theoretical foundations for varieties improvement during phosphorus deficiency and efficient utilization of phosphorus in agricultural production.
Phosphorus is one of the most important nutrients for forage so that soil phosphate fertility is the limiting factor for the growth of forage. This paper summarized the impacts of phosphorus on forage, compared the effects of combined applications of fertilizers on forage, explained the adaptability of forage to low-phosphorus stress, introduced inoculation of fungus on forage and cultivation of phosphorus efficient forage varieties which can improve the adaptability to low-phosphorus. The usage of molecular biology techniques to screen phosphorus efficient forage breeding and germplasm resources is the key to solve the problem of the utilization of effective phosphorus for forage.
Biotic and abiotic stresses such as water deficit, low temperature, pest and disease place major constraints on plant growth and crop productivity. Fatty acids (FAs) and FA-derivatives are unique bioactive substances that show a wide range of functions in biological systems. They are not only important sources of reserve energy and essential components of membrane lipids in plants, but also play significant roles in improving stress tolerance by participating in a variety of defense ways, including basal, effector-triggered, and systemic immunity. In the present paper, the current status of FAs and its derivatives acting in the signaling pathways of plant defense were summarized. Moreover, the existing problems and research tendency were also discussed, expecting to provide the theoretical basis for forage resistance breeding.
The present study evaluated the environment impacts of livestock feces and estimated the quantity capacity of livestock development space in the future by calculating and analyzing data between 2001 and 2010 in Gansu Province. The gross of livestock feces gradually increased. The amounts of livestock discharge varied in different cities and the capacity of livestock feces in each hectare had reached the maximum. The worse part is that cultivated land soil had been polluted in some cities. The influence of livestock increased gradually and presented various effects in different cities. Compared with COD, TN and TP of livestock excrement and urine were main pollutants of the water body. The warning value analysis indicated that livestock feces pollution in Gansu was not serious although it was imbalanced in different area. The livestock had overloaded in some cities like Jiayuguan City, however, cities like Gannan and Dingxi have larger development space.
Based on the deep investigation in Gannan pastoral areas, the scientific connotation of traditional nomadic system was discussed in the view of the natural attributes of grassland, the intrinsic quality of rotational grazing, and the scientificity. The authors considered that the nomadic production mode was adaptive selection of grassland herdsman. It was under restriction of natural attribute of grassland, and can alleviate the situation of grassland over-usage. The traditional nomadic system was the wisdom of long term co-evolution between herdsman and natural grassland. The objective of the paper was to call on re-define about the scientificity of traditional nomad, and further research about the traditional nomadic system.
Ecological environment degradation and farmer poverty have become important constraint factors for the sustainable development of social-economy in minority nationality areas in Gansu Province. As a case study in the Linxia Minority Nationality Areas of Gansu Province and according to ecological, economic and social characteristics of minority nationality areas in Linxia, this study analyzed the current situation of ecological environment deterioration and features of multidimensional poverty of ecological, economic, intellectual and institutional. The present study also investigated the interaction between the farmer poverty and ecological environment deterioration and put forward anti-poverty countermeasures of ecological environment protection and farmer increase income under the condition of ecological compensation from the perspective of sustainable development in minority nationality areas in Linxia of Gansu Province.
The Inner Mongolia grassland ranks first among China’s five major pastoral areas, which is an important ecological defense in north China. However, Inner Mongolia grassland ecosystem has been damaged severely due to climate change and human factors. China has implemented a series of ecological projects to restore and improve grassland ecosystem. This paper analyzed the effects of Beijing and Tianjin sandstorm source control project as well as Returning grazing land to grass project in Inner Mongolia pastoral 33 counties. Based on Inner Mongolia Statistical Yearbook and relevant materials, we found that the project implementation improved ecological, economic and social benefits of Inner Mongolia pastoral area. However, some problems still existed such as low compensation standard, small compensation range, weak input and investment, single compensation subjects, backward regulatory system and other problems. In order to solve these issues, this paper put forward seven aspects of countermeasures and suggestions so as to provide a strong guarantee for the smooth implementation of subsequent grassland ecosystem projects
Forage is important foundation for the development of livestock production. Forage grass contains a variety of essential nutrients and important crude fiber for animal healthy growth. Inappropriate cultivation in pasture farming and other human factors have led to yields and quality reduction and grassland ecological environment deterioration. The application of smash-ridging cultivation could increase more than 20% in forage grass yield and could improve grass quality and effectively improve soil ecological environment. In this paper, the application prospects for smash-ridging on pasture were analysis to provide theoretical reference for improvement of forage grass yield and quality and pasture environment.