[Objective] The aim was to know the pathogenic fungi types and distribution law in ginseng rhizosphere soil.[Method] During May to Oct.in 2008 and 2009,more than 200 soil samples were collected from ginseng rhizospher...[Objective] The aim was to know the pathogenic fungi types and distribution law in ginseng rhizosphere soil.[Method] During May to Oct.in 2008 and 2009,more than 200 soil samples were collected from ginseng rhizosphere soil in Ji an City,Fusong County of Jilin Province and Huanren County of Liaoning Province.Soil dilution plate method and soil particle method were adopted to isolate and culture soil fungi,then classification and identification were carried out.[Result] 33 species of 22 fungal genera were id...展开更多
Fe doped Beta zeolite with different Fe contents were prepared by ion exchange by changing the volume or the concentration of a Fe salt solution. For a particular mass of Fe salt precursor, the concentration of the me...Fe doped Beta zeolite with different Fe contents were prepared by ion exchange by changing the volume or the concentration of a Fe salt solution. For a particular mass of Fe salt precursor, the concentration of the metal salt solution during ion exchange influenced the ion exchange capacity of Fe, and resulted in different activities of the Fe-Beta catalyst. Fe-Beta catalysts with the Fe contents of （2.6, 6.3 and 9） wt% were synthesized using different amounts of 0.02 mol/L Fe salt solution. These catalysts were studied by various characterization techniques and their NH3-SCR activities were evaluated. The Fe-Beta catalyst with the Fe content of 6.3 wt% exhibited the highest activity, with a temperature range of 202-616℃ where the NOx conversion was 〉 80%. The Fe content in Beta zeolite did not influence the structure of Beta zeolite and valence state of Fe. Compared with the Fe-Beta catalysts with low Fe content （2.6 wt%）, Fe-Beta catalysts with 6.3 wt% Fe content possessed more isolated Fe3. active sites which led to its higher NH3-SCR activity. A high capacity for NH3 and NO adsorption, and a high activity for NO oxidation also contributed to the high NH3-SCR activity of the Fe-Beta catalyst with 6.3 wt%. However, when the Fe content was further increased to 9.0 wt%, the amount of FexOy nanoparticles increased while the amount of isolated Fe3＋ active sites was unchanged, which promoted NH3 oxidation and decreased the NH3-SCR activity at high temperature.展开更多
The present study revisited the controversial taxonomic status ofPetaurista yunanensis, P. philippensis, P. hainana, and P. petaurista by using a considerably extended set of morphometrical characters （26 cranial var...The present study revisited the controversial taxonomic status ofPetaurista yunanensis, P. philippensis, P. hainana, and P. petaurista by using a considerably extended set of morphometrical characters （26 cranial variables from 60 adult specimen skulls）. The results revealed no sexual dimorphism in any of the four species but confirmed significant craniometric differences among the four species in both the principal components analysis （PCA） and discriminant function analysis （DFA）, with the greatest distinction observed between P. petaurista and other Petaurista species. Both univariate and multivariate analysis indicated that the morphological differences between P. yunanensis and P. philippensis were less than that between P. philippensis and P. hainana. The morphometric results were concordant in geographic patterns with mtDNA data from previous studies and indicated that P. petaurista, P. hainana, P. philippensis, and P. yunanensis could be recognized as valid species.展开更多
There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak cu...There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak curve which appeared in the early August. The calorific values in inflorescence and dead standing showed a fluctuation and the peak value of inflorescence was in the early September and that of dead standing was in middle June. The seasonal changes of energy standing crop on the above-ground part synchronized with that of the biomass, which presented a single peak curve. The energy allocated to each organ in different seasons was in the order as leaves > stem > inflorescence in middle June, leaves > stem > dead standing > inflorescence in early July, leaves > stem > inflorescence > dead standing in middle July, and leaves > stem > dead standing > inflorescence from August to September. The vertical allocation of energy in the parts of above-ground was that the energy value gradually increased from the surface to the 20 cm high level and the maximum value at the 10 - 20 cin high level which made up 26.91% of energy on the above-ground partion, and then it was decreased. In the under-ground portion, the energy value progressively decreased with depth and the maximum value was at 0 - 10 cm depth layer which made up 69.01% of energy of the under-ground portion.展开更多
[ Objective ] The research aimed to reveal theeffects of excessive Mg^2＋ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2＋ including 0, 40, 80, 120, 160,200,...[ Objective ] The research aimed to reveal theeffects of excessive Mg^2＋ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2＋ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2＋ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2＋ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2＋ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2＋ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.展开更多
[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic me...[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.展开更多
[Objective] This paper aimed to investigate the breeding direction of grain crops in Henan Province. [Method] Superior varieties are the basis of grain yield-increase, and a proper breeding direction is essential for ...[Objective] This paper aimed to investigate the breeding direction of grain crops in Henan Province. [Method] Superior varieties are the basis of grain yield-increase, and a proper breeding direction is essential for breeding of superior varieties. According to the actual situation and production requirements in Henan Province, by using statistical data of grain production, this paper analyzed the current situation and influencing factors of grain production in Henan Province, and summarized the breeding direction of current grain production. [Result] The increase of grain output in Henan Province mainly relies on the increase of grain yield per unit area and is achieved based on the increase of wheat and corn yield. There are several main factors affecting grain production in Henan Province, including the frequent meteorological disasters, low resistance to natural disasters, excessive chemical fertilizer inputs, decreased material conversion efficiency, aggravated pollution of the agricultural surface source, imbalanced quality and the distribution of cultivated land, emphasizing yield traits but neglecting related traits during crop breeding pro- cess, unitary dominant varieties resulting from narrow germplasm resources, and reduced grain-planting population with the migration of rural labor force. On this basis, the grain breeding direction is proposed with high yield, high efficiency, adaptability, stress resistance, specificity and safety, to enhance the grain crop breeding level, breed superior varieties, and realize the intensive use of cultivated land, intensive saving of materials, intensive substitution of labor force, intensive protection of environment and intensive efficiency of technologies by adjusting the breeding direction, thus promoting the sustained and stable development of grain production. [Conclusion] This paper provides basis for the breeding of superior varieties of grain crops and improvement of grain output in Henan Province.展开更多
[Objective] In order to explore the yield potential of cassava, the responses of new cassava varieties to fertilizer quantity was investigated. [Method] A comparative experiment was carried out on 5 new fertilizer-tol...[Objective] In order to explore the yield potential of cassava, the responses of new cassava varieties to fertilizer quantity was investigated. [Method] A comparative experiment was carried out on 5 new fertilizer-tolerant high-yield cassava varieties（Guire 8, Guire 9, Guire 10, Xinxuan 048 and Guiken 09-26） with the normal-level fertilization groups of these varieties as controls. [Result] The results showed that：（1） increasing fertilizers could significantly improve the stem and leaf yield of cassava;（2） increasing fertilizers could reduce the dry matter content of cassava; and（3） different varieties differed in fertilizer tolerance, and the fertilizing amount should be determined according to specific varieties. [Conclusion] Guire 10 and Xinxuan 048 are suitable for being cultivated at a high fertilizer level, and the remaining three varieties（Guiken 09-26, Guire 8 and Guire 9） are suitable for being cultivated at a normal fertilizer level.展开更多
Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this...Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development.展开更多
Abstract Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is cru- cial to understand pelagic ecosystem processes. This study compared the copepod collect...Abstract Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is cru- cial to understand pelagic ecosystem processes. This study compared the copepod collecting efficiency of three commonly used plankton nets, namely, the China standard coarse net （505 gm mesh）, the China standard fine net （77 gin）, and the WP-2 net （200 μm） The experiment was performed at six stations in the Bohai Sea during the autumn of 2012. The coarse net substantially un- der-sampled small individuals （body widths 〈 672 gm） and led to the lowest species number in each tow, whereas the fine net col- lected all small copepod species but failed to collect rare species. The WP-2 net appeared to be a compromise of the two other nets, collecting both small copepods and rare species. The abundance of copepods collected by the coarse net （126.4±86.5 indm-3） was one to two orders of magnitude lower than that by the WP-2 net （5802.4 ± 2595.4 indm3）, and the value of the fine net （11117.0±4563.41 indm-3） was nearly twice that of the WP-2 net. The abundance of large copepods （i.e., adult Calanus sinicus） in the three nets showed no significant differences, but the abundance of small copepods declined with decreasing mesh size. The dif- ference in abundance resulted from the under-sampling of small copepods with body widths 〈 672 μm and 〈 266μm by the coarse and WP-2 nets, respectively.展开更多
Background： Understanding the changes in population dynamics, including demographics, distribution and threats is essential for species status assessing.The endangered Green Peafowl （Povo muticus） has experienced s...Background： Understanding the changes in population dynamics, including demographics, distribution and threats is essential for species status assessing.The endangered Green Peafowl （Povo muticus） has experienced sharp population declines and d stribution range diminishing both in China and Southeast Asia. Field population surveys have not been conducted in China since the 1990s, which hindered conservation planning and decision-making.Methods： With interview and line transects methods, we figured out the population and distribution changes of Green Peafowl across its historical ranges over the past three decades in China during 2014-2017.Results： The Green Peafowl once habituated in 54 counties in China. Nearly 60% of the distribution counties were lost in the past three decades, with the left 22 counties distributed in central, southern and western Yunnan, SW China. Population decrease detected in all distribution areas except for Shuangbai and Xinping county where more than 60% of the total population is located. Only about 30% of the former bird population were recorded with the same interviewing method as 20 years ago.Three birds, 1 carcass, 6 calls and 12 footprints were detected along the 865 km line transects, indicating extremely low encounter rate of Green Peafowl in field. Sharp decreases in flock sizes were also detected, from 8-20 birds per flock in the 1990s to 3-5 birds at present. Poaching and habitat conversion are two widespread and long-lasting threats, while poison tion affect regional population＇s survival. Large flocks of 18 ng caused mortality in the past and hydropower construc -27 birds were discovered in the field, which increases our confidence of population recovery of this endangered pheasant in China.Conclusions： Only interviewed bird number and counts based on line transects were presented in this study, without further population estimation due to limitation of the data sets. Although the actual population of this cryptic bird must be underestimated, dramatic population declines and distribution concentrations of the endangered Green Peafowl occurred over the past 30 years in China undoubtedly.展开更多
The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this f...The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this family of the Rhachiglossa is controversial. We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy. These species are considered to be representatives of two subfamilies, two genera, and 10 subgenera. Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species. We found no support for the subgeneric differentiation of the species. However, the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions. We noted sexual dimorphism in the shape of the teeth in some species, and considerable variability of the shape of teeth within a single species. Based on our results, the genus Nassarius cannot be split into subgenera using radula morphology.展开更多
There are many experimental approaches,field investigations and numerical calculations for movements of woods in a clear water and debris flow.However,kinematic conditions for accumulated logs and the interactions bet...There are many experimental approaches,field investigations and numerical calculations for movements of woods in a clear water and debris flow.However,kinematic conditions for accumulated logs and the interactions between a main flow and logs have not been fully evaluated.Mitigations for woods need taking into account the characteristics of tree species such as conifer and broad-leaf trees and of shapes such as root swells and crown.In the present study,we focus on the differences in specific weight of conifer and broad-leaf trees with some moisture in a sediment-water mixture flow with narrow flow width,and consider that conifer and broad-leaf tree are floating and submerged solid phase,respectively.Flume tests are conducted in steady flow of clear and debris flow over a rigid bed in order to evaluate conifer and broad-leaf tree movement in clear water and debris flow.Experimental data indicates that dimensionless transverse diffusion coefficient can be 0.1 to 0.4 and 0.3 to 0.9 in flow direction.Those diffusive characteristics seem to be independent of Reynolds number and Froude number,but dependent of bed slope,i.e.,gravity,though detailed considerations are needed to discuss about flow characteristics such as spatial eddy structures,momentum transfer induced by interactions of logs and so on.展开更多
Steller chamaejasme L. （S. chamaejasme for short） is one of the most noxious unpalatable weeds in China, which has been frequently reported its negative interaction （i.e. competition and allelopathy） with other he...Steller chamaejasme L. （S. chamaejasme for short） is one of the most noxious unpalatable weeds in China, which has been frequently reported its negative interaction （i.e. competition and allelopathy） with other herbaceous species in grasslands. This study compared species diversity, biomass and sexual reproduction of herbaceous plants in meadows with S. chamaejasme and in open meadows without S. ehamaejasme in overgrazing meadows on the Tibetan Plateau in China to determine whether positive facilitation exist between S. chamaejasme and other herbaceous species under livestock＇s overgrazing. The results showed that there are more herbaceous species in meadows with S. chamaejasme than those in open meadows （35s and30s, respectively）. Diversity index and above-ground biomass were also significantly higher in meadows with S. charnaejasme. There were 39% （11/28） of all species with sexual reproduction found in meadows with S. charnaejasme, which was 7 times more than those in open meadows. Our study showed that S. charnaejasme could provide biotic refuge for neighboring plants and preserve plant diversity from livestock＇s overgrazing in alpine meadows on the Tibetan Plateau. It also suggested that inter-specific facilitation between S. charnaejasme and other herbaceous species may play a key role in overgrazing alpine meadows.展开更多
In spring and summer 2011, the macro- and megabenthic fauna in two sections of the East China Sea were investigated using an Agassiz net trawl to detect the seasonal and spatial variations of benthic community charact...In spring and summer 2011, the macro- and megabenthic fauna in two sections of the East China Sea were investigated using an Agassiz net trawl to detect the seasonal and spatial variations of benthic community characteristics and the relation to environmental variables. The total number of species increased slightly from spring （131 species） to summer （133） whereas the percentage of Mollusca decreased significantly. The index of relative importance （IRI） indicated that the top five important species changed completely from spring to summer. Species number, abundance and biomass in summer were significantly higher than in spring, but no significant difference was observed among areas （coastal, transitional and oceanic areas, divided basically from inshore to offshore）. Species richness （at）, diversity （H） and evenness （J） showed no significant seasonal or spatial variations. Cluster analysis and nMDS ordination identified three benthic communities from inshore to offshore, corresponding to the three areas. Analysis of Similarity （ANOSIM） indicated the overall significant difference in community structure between seasons and among areas. K-dominance curves revealed the high intrinsic diversity in the offshore area. Canonical correspondence analysis showed that the coastal community was positively correlated to total nitrogen and total organic carbon in spring, but negatively in summer; oceanic community was positively correlated to total nitrogen and total organic carbon in both seasons. Species such as Coelorhynchus multispinulosus, Neobythites sivicola, Lepidotrigla alata, Solenocera melantho, Parapenaeus fissuroides, Oratosquilla gonypetes and Spiropagurus spiriger occurred exclusively in the offshore oceanic area and their presence may reflect the influence of the offshore Kuroshio Current.展开更多
Ciliated protozoa play important roles in micro-ecosystems, especially in marine biotopes. However, few studies have been carried out on the periphytic, or aufwuch, forms in mariculture waters so far. In this study, w...Ciliated protozoa play important roles in micro-ecosystems, especially in marine biotopes. However, few studies have been carried out on the periphytic, or aufwuch, forms in mariculture waters so far. In this study, we sampled periphytic ciliate communities in two closed mariculture ponds (ponds CP1 and CP2) and a natural seawater reservoir (pond RP) using a glass slide method to evaluate their colonizing processes and general ecological features, as well as their application as water quality indicators. We analyzed species compositions, structural parameters (species number, richness, diversity, evenness, abundance and dBP) and functional parameters (G, Seq and T90%). Pond RP was characterized by higher levels of structural parameters (except for abundance and dBP) and more equal proportion of the major taxonomic groups. The values of Seq were significantly higher in pond RP and similar in both pond CP1 and CP2. It was also demonstrated that environmental factors, including NO2-H, NO3-H, NH3-H, soluble reactive phosphate, temperature and pH, were the first principal factors affecting the communities. Among them, temperature and chemical factors were all significantly and negatively correlated with species number (P<0.01), richness (P<0.01), diversity (P<0.01), and positive correlated with abundance (P<0.01). Opposite correlations between pH and structural parameters were observed. This study showed that there were significant differences in species composition, structural parameters and functional parameters of the periphytic ciliate communities among the ponds, which were in agreement with the water quality. Results of this study confirmed the periphytic ciliate communities to be useful bioindicators of water quality in intensive mariculture waters.展开更多
The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities （e.g., pollution and overfishing）. Thus, the restoration and protection...The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities （e.g., pollution and overfishing）. Thus, the restoration and protection of fishery resources have become critical and complex. The stability and balanced structure of the fish community is a basic foundation for the protection of fishery resources. Based on data collected from bottom trawls by the R/V Beidou in continental shelf of the East China Sea in November 2006 and February 2007, changes in the composition and diversity of fish species and functional groups were analyzed. The research area was divided into offshore waters and inshore waters by the two-way indicator species analysis （TWIA）. The results showed that the dominant species were different between offshore waters and inshore waters and also varied with the survey time. The most abundant family was Sciaenidae and Teraponidae in November 2006, Sciaenidae, Engraulidae and Triglidae were most abundant in February 2007. The species belonged mainly to mobile piscivores （G6）, benthivores/piscivores （G4）, benthivores （G3） and planktivores （G1）, and the dominant species in November 2006 were commercial species （e.g. Larimichthys polyactis and Trichiurusjaponicus）, but small-sized species were dominant in February 2007 （e.g., Harpadon nehereus, Benthosema pterotum, Champsodon capensis, and Acropoma japonieum）. The species diversity showed a similar trend as the functional group diversity. Stations with higher diversity were mainly distributed in inshore waters in February 2007, whereas higher diversity was found in offshore waters in November 2006. The highest biomass and species number were found in G6 group, followed by the G4, G5 and GI groups. The distribution of the number of individuals of each functional group showed the opposite trend as that of the biomass distribution. In addition, the size spectra were mainly concentrated around 3-29 cm, and the individual number of fish species gradually decreased with the increase in body size, but the relative biomass showed a moderate fluctuation in each size class. These changes showed that species with faster growth rate and earlier maturity age became dominant in continental shelf of the East China Sea. So the variations in biological characteristics of fish should be fully considered in maintaining sustainable utilization of fishery resource.展开更多
The diversity,community structure and seasonal variation in demersal nekton off the Changjiang(Yangtze)River estuary was evaluated using monthly trawl survey data,collected between December 2008 and November 2009.A to...The diversity,community structure and seasonal variation in demersal nekton off the Changjiang(Yangtze)River estuary was evaluated using monthly trawl survey data,collected between December 2008 and November 2009.A total of 95 species(56 teleosts,11 cephalopods,and 28 decapod crustaceans)from 69 genera,49 families and 15 orders were collected.These species could be classifi ed into six groups on the basis of temporal distribution patterns.The resident crab Ovalipes punctatus dominated the community,both in number and biomass.A clear seasonal succession was observed in the species composition.Cluster analysis revealed three primary seasonal groups corresponding to the samples collected in winter-spring,late spring-summer and late summer-autumn.The highest biomass and lowest diversity were observed in summer,while the lowest biomass and highest diversity in winter.The abundance-biomass comparison curves and community composition suggested that the investigated community was moderately disturbed.The results suggest that reduction in fi shing pressure and in the degree of seasonal hypoxia are essential for sustainable resource management off the Changjiang River estuary.展开更多
基金Supported by National Natural Science Foundation of China(30770009)~~
文摘[Objective] The aim was to know the pathogenic fungi types and distribution law in ginseng rhizosphere soil.[Method] During May to Oct.in 2008 and 2009,more than 200 soil samples were collected from ginseng rhizosphere soil in Ji an City,Fusong County of Jilin Province and Huanren County of Liaoning Province.Soil dilution plate method and soil particle method were adopted to isolate and culture soil fungi,then classification and identification were carried out.[Result] 33 species of 22 fungal genera were id...
基金supported by the National Key Basic Research Program of China (973 Program, 2013CB933201)the National Natural Science Foun-dation of China (21577034, 21333003, 91545103)+1 种基金Science and Technology Commission of Shanghai Municipality (16ZR1407900)Fundamental Research Funds for the Central Universities (WJ1514020)~~
文摘Fe doped Beta zeolite with different Fe contents were prepared by ion exchange by changing the volume or the concentration of a Fe salt solution. For a particular mass of Fe salt precursor, the concentration of the metal salt solution during ion exchange influenced the ion exchange capacity of Fe, and resulted in different activities of the Fe-Beta catalyst. Fe-Beta catalysts with the Fe contents of （2.6, 6.3 and 9） wt% were synthesized using different amounts of 0.02 mol/L Fe salt solution. These catalysts were studied by various characterization techniques and their NH3-SCR activities were evaluated. The Fe-Beta catalyst with the Fe content of 6.3 wt% exhibited the highest activity, with a temperature range of 202-616℃ where the NOx conversion was 〉 80%. The Fe content in Beta zeolite did not influence the structure of Beta zeolite and valence state of Fe. Compared with the Fe-Beta catalysts with low Fe content （2.6 wt%）, Fe-Beta catalysts with 6.3 wt% Fe content possessed more isolated Fe3. active sites which led to its higher NH3-SCR activity. A high capacity for NH3 and NO adsorption, and a high activity for NO oxidation also contributed to the high NH3-SCR activity of the Fe-Beta catalyst with 6.3 wt%. However, when the Fe content was further increased to 9.0 wt%, the amount of FexOy nanoparticles increased while the amount of isolated Fe3＋ active sites was unchanged, which promoted NH3 oxidation and decreased the NH3-SCR activity at high temperature.
基金National Natural Science Fund of China (30970332)National Basic Research Program of China (973 Program) (2007CB411600)+1 种基金Natural Science Found of Yunnan Province (2007C099M)Special Subjects Funds of National Natural Science Fund of China (J0930004)
文摘The present study revisited the controversial taxonomic status ofPetaurista yunanensis, P. philippensis, P. hainana, and P. petaurista by using a considerably extended set of morphometrical characters （26 cranial variables from 60 adult specimen skulls）. The results revealed no sexual dimorphism in any of the four species but confirmed significant craniometric differences among the four species in both the principal components analysis （PCA） and discriminant function analysis （DFA）, with the greatest distinction observed between P. petaurista and other Petaurista species. Both univariate and multivariate analysis indicated that the morphological differences between P. yunanensis and P. philippensis were less than that between P. philippensis and P. hainana. The morphometric results were concordant in geographic patterns with mtDNA data from previous studies and indicated that P. petaurista, P. hainana, P. philippensis, and P. yunanensis could be recognized as valid species.
文摘There were two peaks of seasonal changes of the calorific value in shoot and leaves of Calamagrostis epigejos in middle June and in the early August respectively. The calorific value in stem presented a single peak curve which appeared in the early August. The calorific values in inflorescence and dead standing showed a fluctuation and the peak value of inflorescence was in the early September and that of dead standing was in middle June. The seasonal changes of energy standing crop on the above-ground part synchronized with that of the biomass, which presented a single peak curve. The energy allocated to each organ in different seasons was in the order as leaves > stem > inflorescence in middle June, leaves > stem > dead standing > inflorescence in early July, leaves > stem > inflorescence > dead standing in middle July, and leaves > stem > dead standing > inflorescence from August to September. The vertical allocation of energy in the parts of above-ground was that the energy value gradually increased from the surface to the 20 cm high level and the maximum value at the 10 - 20 cin high level which made up 26.91% of energy on the above-ground partion, and then it was decreased. In the under-ground portion, the energy value progressively decreased with depth and the maximum value was at 0 - 10 cm depth layer which made up 69.01% of energy of the under-ground portion.
基金Key Project of‘Rejuvenating the Northeast China’ Science and Technology Action Plan of Chinese Academy of Sciences(DB2X-2-027)National Key Basic Research Program(2004CB418506)~~
文摘[ Objective ] The research aimed to reveal theeffects of excessive Mg^2＋ on the germination characteristics of maize and soybean. [ Method ] Eleven concentration gradients of Mg^2＋ including 0, 40, 80, 120, 160,200,240,280,320,360 and 400 mmol/L were set up to study the effects of different treatments on such indices as the germination potential, germination rate, fresh weight, dry weight, root length, plant height and stem diameter of maize and soybean. [ Result] With the increasing of Mg^2＋ concentration, the germination of maize delayed and the germination rate of soybean obviously decreased, reaching the significant difference at 0.05 level. When Mg^2＋ concentration increased, the fresh weight and dry weight of maize and soybean decreased, but maize and soybean showed some adaptability. The growth of radicles and seedlings in maize and soybean were obviously inhibited by Mg^2＋ , and atrophy and dysplasia phenomena appeared. [ Conclusion] Excessive Mg^2＋ stress has different effects on the germination potential and germination rate of different crops and has obvious poisoning effects on the root and stem growth of crops.
基金Supported by Joint Research Fund from National Natural Science Foundation of China(NSFC)-Yunnan Province(U0933601)Students Research Fund from Southwest Forestry University(1001)~~
文摘[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.
基金Supported by Special Fund of Henan Provincial Department of Finance(2012-196-58)~~
文摘[Objective] This paper aimed to investigate the breeding direction of grain crops in Henan Province. [Method] Superior varieties are the basis of grain yield-increase, and a proper breeding direction is essential for breeding of superior varieties. According to the actual situation and production requirements in Henan Province, by using statistical data of grain production, this paper analyzed the current situation and influencing factors of grain production in Henan Province, and summarized the breeding direction of current grain production. [Result] The increase of grain output in Henan Province mainly relies on the increase of grain yield per unit area and is achieved based on the increase of wheat and corn yield. There are several main factors affecting grain production in Henan Province, including the frequent meteorological disasters, low resistance to natural disasters, excessive chemical fertilizer inputs, decreased material conversion efficiency, aggravated pollution of the agricultural surface source, imbalanced quality and the distribution of cultivated land, emphasizing yield traits but neglecting related traits during crop breeding pro- cess, unitary dominant varieties resulting from narrow germplasm resources, and reduced grain-planting population with the migration of rural labor force. On this basis, the grain breeding direction is proposed with high yield, high efficiency, adaptability, stress resistance, specificity and safety, to enhance the grain crop breeding level, breed superior varieties, and realize the intensive use of cultivated land, intensive saving of materials, intensive substitution of labor force, intensive protection of environment and intensive efficiency of technologies by adjusting the breeding direction, thus promoting the sustained and stable development of grain production. [Conclusion] This paper provides basis for the breeding of superior varieties of grain crops and improvement of grain output in Henan Province.
基金Supported by the Earmarked Fund for China Agriculture Research System(CARS-12-cssy)~~
文摘[Objective] In order to explore the yield potential of cassava, the responses of new cassava varieties to fertilizer quantity was investigated. [Method] A comparative experiment was carried out on 5 new fertilizer-tolerant high-yield cassava varieties（Guire 8, Guire 9, Guire 10, Xinxuan 048 and Guiken 09-26） with the normal-level fertilization groups of these varieties as controls. [Result] The results showed that：（1） increasing fertilizers could significantly improve the stem and leaf yield of cassava;（2） increasing fertilizers could reduce the dry matter content of cassava; and（3） different varieties differed in fertilizer tolerance, and the fertilizing amount should be determined according to specific varieties. [Conclusion] Guire 10 and Xinxuan 048 are suitable for being cultivated at a high fertilizer level, and the remaining three varieties（Guiken 09-26, Guire 8 and Guire 9） are suitable for being cultivated at a normal fertilizer level.
文摘Cropping structure has a close relationship with the optimal allocation of agricultural water resources. Based on the analysis of the relationship between agricultural water resources and sustainable development, this paper presents a multi objective fuzzy optimization model for cropping structure and water allocation, which overcomes the shortcoming of current models that only considered the economic objective,and ignored the social and environmental objectives. During the process, a new method named fuzzy deciding weight is developed to decide the objective weight. A case study shows that the model is reliable, the method is simple and objective, and the results are reasonable. This model is useful for agricultural management and sustainable development.
基金funded by the Fundamental Research Funds for the Central Universities (No.201262017)the National Natural Science Foundation of China (No.41210008)
文摘Abstract Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is cru- cial to understand pelagic ecosystem processes. This study compared the copepod collecting efficiency of three commonly used plankton nets, namely, the China standard coarse net （505 gm mesh）, the China standard fine net （77 gin）, and the WP-2 net （200 μm） The experiment was performed at six stations in the Bohai Sea during the autumn of 2012. The coarse net substantially un- der-sampled small individuals （body widths 〈 672 gm） and led to the lowest species number in each tow, whereas the fine net col- lected all small copepod species but failed to collect rare species. The WP-2 net appeared to be a compromise of the two other nets, collecting both small copepods and rare species. The abundance of copepods collected by the coarse net （126.4±86.5 indm-3） was one to two orders of magnitude lower than that by the WP-2 net （5802.4 ± 2595.4 indm3）, and the value of the fine net （11117.0±4563.41 indm-3） was nearly twice that of the WP-2 net. The abundance of large copepods （i.e., adult Calanus sinicus） in the three nets showed no significant differences, but the abundance of small copepods declined with decreasing mesh size. The dif- ference in abundance resulted from the under-sampling of small copepods with body widths 〈 672 μm and 〈 266μm by the coarse and WP-2 nets, respectively.
基金the financial supports from the Biodiversity Conservation Fund from Yunnan Environmental Protection DepartmentSpecial Funds for Green Peafowl Investigation from State Forestry Administration of the People’s Republic of Chinasupported by the Key Laboratory of Special Biological Resource Development and Utilization of Universities in Yunnan Province
文摘Background： Understanding the changes in population dynamics, including demographics, distribution and threats is essential for species status assessing.The endangered Green Peafowl （Povo muticus） has experienced sharp population declines and d stribution range diminishing both in China and Southeast Asia. Field population surveys have not been conducted in China since the 1990s, which hindered conservation planning and decision-making.Methods： With interview and line transects methods, we figured out the population and distribution changes of Green Peafowl across its historical ranges over the past three decades in China during 2014-2017.Results： The Green Peafowl once habituated in 54 counties in China. Nearly 60% of the distribution counties were lost in the past three decades, with the left 22 counties distributed in central, southern and western Yunnan, SW China. Population decrease detected in all distribution areas except for Shuangbai and Xinping county where more than 60% of the total population is located. Only about 30% of the former bird population were recorded with the same interviewing method as 20 years ago.Three birds, 1 carcass, 6 calls and 12 footprints were detected along the 865 km line transects, indicating extremely low encounter rate of Green Peafowl in field. Sharp decreases in flock sizes were also detected, from 8-20 birds per flock in the 1990s to 3-5 birds at present. Poaching and habitat conversion are two widespread and long-lasting threats, while poison tion affect regional population＇s survival. Large flocks of 18 ng caused mortality in the past and hydropower construc -27 birds were discovered in the field, which increases our confidence of population recovery of this endangered pheasant in China.Conclusions： Only interviewed bird number and counts based on line transects were presented in this study, without further population estimation due to limitation of the data sets. Although the actual population of this cryptic bird must be underestimated, dramatic population declines and distribution concentrations of the endangered Green Peafowl occurred over the past 30 years in China undoubtedly.
基金Supported by the National Natural Science Foundation of China (No. 41076104)the Knowledge Innovation Program of Chinese Academy of Sciences (No. KSCX2-YW-Z-0916)the Knowledge Innovation Program of Institute of Oceanology, Chinese Academy of Sciences (No. 2007-12)
文摘The family Nassariidae includes a number of species that are distributed throughout the world. Each species has a characteristic shell shape, tooth shape, and behavior. However, the classification of species in this family of the Rhachiglossa is controversial. We describe the radulae of 22 species from China in detail using optical and scanning electron microscopy. These species are considered to be representatives of two subfamilies, two genera, and 10 subgenera. Our results suggest that the morphology of the central tooth and the pair of lateral teeth and the presence or absence of a pair of intermediate accessory lateral teeth could be used to distinguish among species. We found no support for the subgeneric differentiation of the species. However, the presence or absence of the intermediate lateral accessory plate was characteristic of species divisions. We noted sexual dimorphism in the shape of the teeth in some species, and considerable variability of the shape of teeth within a single species. Based on our results, the genus Nassarius cannot be split into subgenera using radula morphology.
基金supported by Research Budget from Research and Development Center,NIPPON KOEI Co.,Ltd (Research theme:Modeling for debris flow with woods and their applicability)
文摘There are many experimental approaches,field investigations and numerical calculations for movements of woods in a clear water and debris flow.However,kinematic conditions for accumulated logs and the interactions between a main flow and logs have not been fully evaluated.Mitigations for woods need taking into account the characteristics of tree species such as conifer and broad-leaf trees and of shapes such as root swells and crown.In the present study,we focus on the differences in specific weight of conifer and broad-leaf trees with some moisture in a sediment-water mixture flow with narrow flow width,and consider that conifer and broad-leaf tree are floating and submerged solid phase,respectively.Flume tests are conducted in steady flow of clear and debris flow over a rigid bed in order to evaluate conifer and broad-leaf tree movement in clear water and debris flow.Experimental data indicates that dimensionless transverse diffusion coefficient can be 0.1 to 0.4 and 0.3 to 0.9 in flow direction.Those diffusive characteristics seem to be independent of Reynolds number and Froude number,but dependent of bed slope,i.e.,gravity,though detailed considerations are needed to discuss about flow characteristics such as spatial eddy structures,momentum transfer induced by interactions of logs and so on.
基金funded by the National Natural Science Foundation of China (Grant Nos. 31100360, 31200378, 31000233)
文摘Steller chamaejasme L. （S. chamaejasme for short） is one of the most noxious unpalatable weeds in China, which has been frequently reported its negative interaction （i.e. competition and allelopathy） with other herbaceous species in grasslands. This study compared species diversity, biomass and sexual reproduction of herbaceous plants in meadows with S. chamaejasme and in open meadows without S. ehamaejasme in overgrazing meadows on the Tibetan Plateau in China to determine whether positive facilitation exist between S. chamaejasme and other herbaceous species under livestock＇s overgrazing. The results showed that there are more herbaceous species in meadows with S. chamaejasme than those in open meadows （35s and30s, respectively）. Diversity index and above-ground biomass were also significantly higher in meadows with S. charnaejasme. There were 39% （11/28） of all species with sexual reproduction found in meadows with S. charnaejasme, which was 7 times more than those in open meadows. Our study showed that S. charnaejasme could provide biotic refuge for neighboring plants and preserve plant diversity from livestock＇s overgrazing in alpine meadows on the Tibetan Plateau. It also suggested that inter-specific facilitation between S. charnaejasme and other herbaceous species may play a key role in overgrazing alpine meadows.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA11020303)the Ocean Public Welfare Scientifi c Research Project,State Oceanic Administration of the PRC(No.201505004)the National Natural Science Foundation of China(Nos.41176133,41406157)
文摘In spring and summer 2011, the macro- and megabenthic fauna in two sections of the East China Sea were investigated using an Agassiz net trawl to detect the seasonal and spatial variations of benthic community characteristics and the relation to environmental variables. The total number of species increased slightly from spring （131 species） to summer （133） whereas the percentage of Mollusca decreased significantly. The index of relative importance （IRI） indicated that the top five important species changed completely from spring to summer. Species number, abundance and biomass in summer were significantly higher than in spring, but no significant difference was observed among areas （coastal, transitional and oceanic areas, divided basically from inshore to offshore）. Species richness （at）, diversity （H） and evenness （J） showed no significant seasonal or spatial variations. Cluster analysis and nMDS ordination identified three benthic communities from inshore to offshore, corresponding to the three areas. Analysis of Similarity （ANOSIM） indicated the overall significant difference in community structure between seasons and among areas. K-dominance curves revealed the high intrinsic diversity in the offshore area. Canonical correspondence analysis showed that the coastal community was positively correlated to total nitrogen and total organic carbon in spring, but negatively in summer; oceanic community was positively correlated to total nitrogen and total organic carbon in both seasons. Species such as Coelorhynchus multispinulosus, Neobythites sivicola, Lepidotrigla alata, Solenocera melantho, Parapenaeus fissuroides, Oratosquilla gonypetes and Spiropagurus spiriger occurred exclusively in the offshore oceanic area and their presence may reflect the influence of the offshore Kuroshio Current.
基金Supported by the National Natural Science Foundation of China (Nos.U0633006,30700069,41076089)from the Center of Excellence in Biodiversity Research,King Saud University
文摘Ciliated protozoa play important roles in micro-ecosystems, especially in marine biotopes. However, few studies have been carried out on the periphytic, or aufwuch, forms in mariculture waters so far. In this study, we sampled periphytic ciliate communities in two closed mariculture ponds (ponds CP1 and CP2) and a natural seawater reservoir (pond RP) using a glass slide method to evaluate their colonizing processes and general ecological features, as well as their application as water quality indicators. We analyzed species compositions, structural parameters (species number, richness, diversity, evenness, abundance and dBP) and functional parameters (G, Seq and T90%). Pond RP was characterized by higher levels of structural parameters (except for abundance and dBP) and more equal proportion of the major taxonomic groups. The values of Seq were significantly higher in pond RP and similar in both pond CP1 and CP2. It was also demonstrated that environmental factors, including NO2-H, NO3-H, NH3-H, soluble reactive phosphate, temperature and pH, were the first principal factors affecting the communities. Among them, temperature and chemical factors were all significantly and negatively correlated with species number (P<0.01), richness (P<0.01), diversity (P<0.01), and positive correlated with abundance (P<0.01). Opposite correlations between pH and structural parameters were observed. This study showed that there were significant differences in species composition, structural parameters and functional parameters of the periphytic ciliate communities among the ponds, which were in agreement with the water quality. Results of this study confirmed the periphytic ciliate communities to be useful bioindicators of water quality in intensive mariculture waters.
基金Supported by the Key Project of National Natural Science Foundation of China(No.31061160187)the National Basic Research Program of China(973 Program)(No.2010CB951204)+1 种基金Taishan Scholar Program of Shandong ProvinceYellow & Bohai Sea Scientific Observation and Experiment Station for Fishery Resources and Environment,Ministry of Agriculture
文摘The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities （e.g., pollution and overfishing）. Thus, the restoration and protection of fishery resources have become critical and complex. The stability and balanced structure of the fish community is a basic foundation for the protection of fishery resources. Based on data collected from bottom trawls by the R/V Beidou in continental shelf of the East China Sea in November 2006 and February 2007, changes in the composition and diversity of fish species and functional groups were analyzed. The research area was divided into offshore waters and inshore waters by the two-way indicator species analysis （TWIA）. The results showed that the dominant species were different between offshore waters and inshore waters and also varied with the survey time. The most abundant family was Sciaenidae and Teraponidae in November 2006, Sciaenidae, Engraulidae and Triglidae were most abundant in February 2007. The species belonged mainly to mobile piscivores （G6）, benthivores/piscivores （G4）, benthivores （G3） and planktivores （G1）, and the dominant species in November 2006 were commercial species （e.g. Larimichthys polyactis and Trichiurusjaponicus）, but small-sized species were dominant in February 2007 （e.g., Harpadon nehereus, Benthosema pterotum, Champsodon capensis, and Acropoma japonieum）. The species diversity showed a similar trend as the functional group diversity. Stations with higher diversity were mainly distributed in inshore waters in February 2007, whereas higher diversity was found in offshore waters in November 2006. The highest biomass and species number were found in G6 group, followed by the G4, G5 and GI groups. The distribution of the number of individuals of each functional group showed the opposite trend as that of the biomass distribution. In addition, the size spectra were mainly concentrated around 3-29 cm, and the individual number of fish species gradually decreased with the increase in body size, but the relative biomass showed a moderate fluctuation in each size class. These changes showed that species with faster growth rate and earlier maturity age became dominant in continental shelf of the East China Sea. So the variations in biological characteristics of fish should be fully considered in maintaining sustainable utilization of fishery resource.
基金Supported by the National Key Technology R&D Program of China(No.2007BAD43B01)the National Special Research Fund for Non-Profit Sector(Agriculture)(No.201303047)the Special Fund of Chinese Central Government for Basic Scientific Research Operations in Commonweal Research Institutes(No.2008T04)
文摘The diversity,community structure and seasonal variation in demersal nekton off the Changjiang(Yangtze)River estuary was evaluated using monthly trawl survey data,collected between December 2008 and November 2009.A total of 95 species(56 teleosts,11 cephalopods,and 28 decapod crustaceans)from 69 genera,49 families and 15 orders were collected.These species could be classifi ed into six groups on the basis of temporal distribution patterns.The resident crab Ovalipes punctatus dominated the community,both in number and biomass.A clear seasonal succession was observed in the species composition.Cluster analysis revealed three primary seasonal groups corresponding to the samples collected in winter-spring,late spring-summer and late summer-autumn.The highest biomass and lowest diversity were observed in summer,while the lowest biomass and highest diversity in winter.The abundance-biomass comparison curves and community composition suggested that the investigated community was moderately disturbed.The results suggest that reduction in fi shing pressure and in the degree of seasonal hypoxia are essential for sustainable resource management off the Changjiang River estuary.
