A study on the physiological changes of Elaeocarpus sylvestris and Castanopsis fissa seedlings was conducted under drought stress using treatments of different PEG6000 concentration(mild stress, moderate stress, severe stress) and different stress duration(12 hours, 24 hours, 36 hours), and 1/2 Hoagland nutrient solution without PEG6000 was used as control.Resistance of the seedlings to drought stress was evaluated by testing relative water content, relative conductivity, free proline content, chlorophyll content, super oxide dismutase(SOD) activity, malondidehyde(MDA) content and soluble sugar content.The results showed that with increasing stress intensity and prolonging duration, relative water content of the two seedlings decreased, and that of the C.fissa decreased greater than E.sylvestris;their relative conductivities showed a fluctuant increase.Compared to the control, relative conductivity of C.fissa increased more significantly than E.sylvestris;the contents of free proline of two seedlings increased significantly; contents of chlorophyll fluctuated slightly;the activities of SOD increased at the beginning of drought treatment, but decreased later;contents of soluble sugar increased with increasing stress intensity and prolonging duration.The MDA content of E.sylvestris increased slowly, whereas that of C.fissa increased rapidly.The present study indicates that E.sylvestris is more resistant to drought stress than C.fissa, and that relative water content, relative conductivity and MDA content can be as indicators for drought resistance evaluation for the two seedlings.
The macrobenthic community was analyzed after collecting the macrobenthic fauna from 8 intertidal stations in Zhongjieshan archipelago(Miaozhihu, Qingbang, Huangxing and Dongfu) during Sept., 2006 and July, 2007.Thirty-four species were found in the stations, including 1 species ofCoelenterata, 3 species of Annelida, 10 species of Crustacean and 20 species of Mollusca.The results of the relative important value analysis indicated that 4 species, such as Tetraclitajaponica, Mytilus edulis and Turb articulatus and so on were dominant species.The results of two-way ANOVA about diversity index of the rock intertidal macrobenthic fauna in Zhongjieshan archipelago showed that the diversity index was not significantly different among stations and seasons, but species richness index(D) differed between spring and autumn.The results of Cluster and MDS analysis of 12 stations from 3 tidal zones and 4 islands indicated that the rocky intertidal macrobenthic community constituted three groups(namely, groupⅠ, ⅡandⅢ).The ABC curves indicated that the macrobenthic fauna in the rocky intertidal zone was not disturbed in Zhongjieshan archipelago.
A composite bio-remediation technology including oxidation pond and biological restore technology in river course was employed in the treatment of polluted Guliao River of Guangzhou.Monitoring of water quality and zooplankton was conducted to compare population composition and indicator species of zooplankton at four restoration stages of the river:original water, oxidation pond, upstream and downstream areas of the restored river.The results showed that CODCr, BOD5, nitrogen and phosphorus in the river water were removed gradually during the remediation process, and the diaphaneity was increased greatly, indicating that water quality was improved significantly.After the bioremediation of polluted urban river water, the zooplankton community structure changed significantly.The biodiversity and evenness were raised greatly, and the species and population of zooplankton increased considerably, especially for rotifer.In the restored river water, the predominant species of rotifer changed from Brachionus capsuliflorus to Brachionus angularis and Brachionus rubens, and the predominant species of cladocerans was Moina micrura. Naupii was dominant in quantity in the copepod zooplankton.Indicator zooplankton suitable for remediation of polluted urban river water included:Brachionus capsuliflorus, Brachionus angularis, Brachionus rubens, Keratella cochlearis, Pedalia mira, Collotheca sp., Naupii and Moina micrura.
The species composition, floristic distribution, and characteristics of submerged plant community in Wu River, Qu River and Ou River in the southwest of Zhejiang Province were surveyed during 2007 and 2008.The results showed that:(1) There were 19 species belonging to 6 families and 8 genera.Three areal-types were classified from these genera, and 7 areal-types were classified from species, and the main distribution types between these two levels were different.(2) Thirteen submerged plant communities in 9 typical sites were analyzed by β- and γ- diversity indexes.The β- diversity Jaccard index showed the species comparability of 89.2% communities was lower than 0.5.The highest γ- diversity index(14 species) was found in Qu River, while the lowestγ-diversity index(9 species) was observed in Ou River, which was consistent with the community distribution in other different rivers.It suggests that the low diversity of submerged plants in this area is due to interaction of environment factors and disturbance of human activities.
To provide some basic data for raising and protecting the national key protected wild plant of Pinus kwangtungensis, the survival rate, stem height and stem base diameter of the plant seedlings of different ages cultivated in different ways were determined from May, 2006 to July, 2008 in Nanling National Nature Reserves.Results showed that the survival rates of the seedling groups cultivated in nutrient bags decreased from 100% at the beginning of May, 2006 to 50% by the end of experiment in July, 2008;meanwhile, the rates of the seedlings cultivated in soil and seedlings transplanted from the nature P. kwangtungensis community decreased from 100% to about 80% at the beginning to the end of experiment.Total monthly increments of plant height and stem base diameter for root-bagged seedlings were 1.01 cm and 1.39 cm, for non-bagged seedlings 2.76 cm and 0.17 mm, for transplanted seedlings 0.20 mm and 0.64 mm.Annual increments of plant height and stem base diameter for root-bagged seedlings were 12.77 cm and 17.22 cm, for non-bagged seedling 32.91cm and 1.97mm, for transplanted seedlings 2.31 mm and 7.64 mm.As the seedlings grew, the stem height and stem base diameter of the plants increased rapidly.A significantly positive relationship between plant height and stem base diameter of the seedlings was found, and the seedlings of P.kwangtungensis grew rapidly up to the age of 10 years.
Niche breadths and overlaps of dominant species in restoring succession processes plant community in Huangpuchuan Watershed were measured using a series of indices proposed by Levins, Shannon-Wiener, and ecological significance of niche breadths and overlaps of each community was analyzed.The results show that each typical community is marked absolutely by one species with the largest niche breadth.Dynamic changes of niche breadth in restoring succession are correspondingly related with the changes of populations.Greater niche overlaps will result in more similarities in ecology and resource use of populations, thus leads to a more intense interspecific competition.Competition is a potential dynamic mechanism promoting different plant communities to the climax community in the watershed.
In order to understand the relationship between chlorophyll fluorescence and biomass of microalgae, the fluorescences of six typical marine red tide microalgae in different growth phases(exponential growth phase and steady growth phase) are measured using TD-700 fluorometer;meanwhile the cell density is counted under light microscrope and cell size is determined using Leica Qwin software.The results show that there is a significantly positive relationship between fluorescent value and the cell density in the same growth phase and also in the different growth phases.The results suggest that chlorophyll fluorescence is a quick and reliable method to determine microalgal biomass.
The printed matter about Camellia changii Ye was distributed as separates in 1985 Annual Academic Congress of Botanical Society of Guangdong Province, according to the articles 29.1, 30.4, 31.1 of the International Code of Botanical Nomenclature(Vienna, 2005), it is certified as an effective and valid name of publication in 1985, and based on the Principle of Priority, C.changii is earlier than C.azalea in publication date.That Professor Chang Hung Ta treated C.azalea Wei as a later synonym of C.changii Ye in China Flora (Chinese edition) should be respected by people.
We evaluated the performance of an imported microcystin ELISA(enzyme-linked-immuno-absborbed assay) kit in the study.The ELISA kit was evaluated by the precision test, MC-LR standard recovery test, cross-reactivity test and a test of comparison with an ELISA method based on the monoclonal antibodies(M8H5).The CVs for intra-assay was very low and that for inter-assay was relatively high.Recovery rate was from 73.5%to 97.8%.The kit showed a high cross-reactivity rate to MC-LR, but a low cross-reactivity rate to other microcystin variants such as MC-RR, MC-LW and MC-LF.ELISA analysis of water samples revealed that the results from two ELISA methods were nearly consistent.The Beacon microcystin plate kit can meet the requirements for qualitative and quantitative detection of MC-LR in water.
The activity rhythm of 28 house-hold sika deer was observed by using scan sampling and all-occurrence recording methods from April to August, 2007.The results showed the frequencies of eating, ruminating, relaxing, observing, removing and grooming behavior decreased by turns, and the frequencies of eating and relaxing behavior occupied 80% in all diurnal activities. There were two peaks for the frequencies of eating and ruminating at about 7:30 and 17:30.The peak for the frequencies of relaxing was from 11:00 to 14:00.The difference among the male, the female and the young in eating and relaxing behavior was analyzed, and the results showed there was significant difference in eating behavior in the period of 9:30-11:30 and 12:30-17:30 for the old and the young.In the period of 7:30-8:30, 9:30-10:30 and 12:30-17:30, there was significant difference in relaxing behavior between the male and the female.Our results can provide some basic theory for breeding and protecting sika deer.
The effects of pH value, salinity, glucose and ions solutions on the sperm vitality of Csiaenops ocellatus were investigated by measuring the activation ration, moving time and life-span of sperm.The results indicated that the average density of sperm was (1.203±0.22)×1010·ml-1 and the suitable salinity for sperm activation and movement was 20-35, while pH value 6.0～8.5.The activation rate, moving time and life-ban of sperm reached to 94.32%, 9.14 min and 12.55 min respectively when the sperm was activated in salinity 25.The proper concentration of KCl, NaCl, CaCl2 solutions for sperm activation and movement was 600～700 mmol·L-1, 600 mmol·L-1 and 400～600 mmol·L-1 respectively, while the proper concentration of glucose solution was 700～900mmol·L-1.No significant differences were found in the activation rate when the sperm was activated by the artificial seawater lacking of HCO3-, Mg2+ or Ca2+, but the moving time and survival time of sperm became shorter.
Spatial and temporal distribution of fish larvae in the Buha River, Qinhai Lake was investigated from 1 July to 6 October, 2008 by sampling with hydrographic cableways and conical nets.The results showed that almost all fish larvae were Gymnocypris przewalskii.Fish fry mainly appeared in July, with the average density of 3.17 ind.·m3, and max density of 54 ind.·m3.There were significant differences in the density between the day from 14:00 to 14:10 and the night from 22:00 to 22:10(a=0.05, F=6.13, P=0.014).Fish larvae mainly drifted in the night, and fish fry mostly distributed near the surface and the density of fish fry near shore was higher than the density in river center, while fish eggs mostly distributed near the bottom of river.The density of fish eggs was significantly different, with 0.075 ind.·m3 in the surface, while 0.175 ind.·m-3 in the bottom(n=ll, F=4.73385, P=0.04174).Sectional coefficient offish fry and fish eggs was 0.43 and 2.32 respectively.It is very important to understand the characteristics of spatial and temporal distribution of Gymnocypris przewalskii for larval resource investigation and protection.
We measured the sexual dimorphism in morphological traits, including the body length, head length, head width, head depth, snout length, postorbital head length, eye diameter, interorbital width, body depth, caudal peduncle length, caudal peduncle depth, caudal fin length, dorsal fin precoxal length, dorsal fin coxal length, pelvic fin precoxal length, length between pelvic fin and anal fin, body mass, carcass mass of Abbottina kiatingensis from Oujiang river, Lishui City, Zhejiang Province in reproductive season.Our results showed that the number of adult males was larger than that of females and there was no sexual dimorphism in the body length.The females with special body length were significantly shorter than the males in head length, head width, head depth, snout length, postorbital head length, caudal peduncle depth, dorsal fin precoxal length, dorsal fin coxal length and carcass mass.There was no significant sexual difference among other morphological traits.The individual fecundity was positively correlated with the body length and body mass in A.kiatingensis.A conclusion has been drawn that adult females increased the individual fecundity through increasing the individual size(body length and body mass).
The chemical indicators of water were determined and the growth of loach(Misgurnus anguillicaudatus Cantor) was observed after applied Bacillus subtilis in the loach culture water.The results showed that Bacillus subtilis could stabilize the pH of culture water, and remove CODMn, TN and NO3--N obviously with the degradation rate of 1.2, 0.24 and 2.7 g·L-1·d-1.TP fluctuated in a certain range.When the concentration of Bacillus subtilis was higher than 149 mL·L-1, the change of loach weight decreased with the increasing of concentrations.Therefore, the water quality of loach culture pond was improved obviously.
Partial mitochondrial DNA Cytochrome b gene in Ochetobius elogatus from Miluojiang River and Liujiang River was sequenced and analyzed in present study.Six haplotypes were determined, of which 19 variable sites and 15 parsimony-informatic sites were found.AT content and GC content were 57.6% and 42.4%, respectively.On the neighbor-joining tree based on Kimura-2 parameter model, individuals from Miluojiang River and Liujiang River were clustered separately. Genetic variation among 4 individuals from Miluojiang population was 0.001-0.007, and that between 2 individual of Liujiang population was 0.001.Genetic variation between 2 populations ranged from 0.013 to 0.017 with an average of 0.015.The results indicated that genetic variation was much greater between populations than within populations, and genetic differentiation was obvious between Miluojiang population and Liujiang population.However, the conclusion about genetic variation in the two rivers should be further validated by collecting more samples from more locations.
Based on the technology of GPS, GIS and RS, the functional changes and landscape structure of Qinghai Lake watershed ecosystem are analyzed by using of shadow project approach, market value approach, travel cost approach, carbon tax approach, energy substitute method and NPP model.On the basis of ecosystem service values and regional landscape values, the upper and lower limits for regional eco-compensation standards in Qinghai Lake watershed are put forward.The results show that upper limit of ecological compensation is 84.195 billion yuan, and the lower one is 25.073 billion yuan in Qinghai Lake watershed.The results of this research will provide a scientific basis for the eco-compensation in Qinghai Lake watershed.
By the monitoring and chemical analysis of wet deposition at Liuxihe, Guangzhou, 106 rainwater samples with rainfall depth from 0.7 mm to 268.6 mm were collected and tested during the period from July, 2006 to May, 2008.The relationship between electrical conductivity(EC) and main ions' concentration in the precipitation was studied and discussed in this paper. The results indicated that:(1) Mean relative error between the measured data and the calculated data of EC was -2.94%.(2) The positive correlation between concentration of H+ and EC was found in the rainwater with pH<.5.6 and the negative correlation occurred in the rainwater with pH≥5.6.(3) EC increased with the increase of total ions concentration, nevertheless, when the H+ concentration and the total ions concentration were the same, there were also obvious EC differences among the rainwater samples duo to significant differences of chemical components.(4) After dividing rainwater into two groups(pH<5.6 and pH≥5.6), there existed better relations between EC and ion concentrations, so the concentrations of some ions can be calculated or forecasted by the regression functions and the measured pH value and EC.
A comparison study was made on morphology, biology, and ecology of Bactrocera (Tetradacus) minax (Enderlein), Bactrocera (Bactrocera) dorsalis (Hendel), and Bactrocera (Zeugodacus) cucurbitae (Coquillett). Their distribution, host, morphological characteristics, growth stage and life history were studied; besides, the damage of these species to their hosts and the control measures were also presented. The results are beneficial to the identification of the species and their management.
Wetland ecosystems have gained more and more attention from ecologists for their important ecological functions and social-economic values in recent years.However, many wetland ecosystems all over the world have been lost or are facing a serious threat presently from natural and social factors.Wetland ecosystems are becoming a focus of ecology.In recent years, the studies on wetland ecosystems have concentrated on four main areas, i.e., the investigations on basic information, dynamics, restoration and management of wetland ecosystems.Many new methods and techniques have been used widely in wetland ecosystem studies.The restoration and reconstructing methods of artificial wetlands, as well as their evaluation, have gotten more and more attention from scientists.Natural and social-economic factors may affect the function, structure, and dynamic of wetland ecosystems.Different types of wetland ecosystems have different characteristics.So it is necessary to conduct the study on structure, function and dynamics of wetland ecosystems in broader regions.Additionally, more attentions should be paid to the study of the key techniques(including selection of species) in restoration and rebuilding of wetlands.
