bluuebunny/crossref_metadata_2025 huggingface dataset:
Recovery Dynamics of Vegetation and Soil Properties in Karst Rocky Desertification Areas in Guizhou, China
Authors: Liu Hong Yan , Liu Fang
Published: June 2012

Abstract. Dynamics of vegetation and soil properties responses to vegetation recovery in the selected 72 Karst desertification sites in Guizhou, China were studied. Six typical and representative vegetation types along a chronosequence of vegetation recovery (corn land, sparse grass, regeneration forest, shrub, grass and shrub, and native forest with 0, 3-5, 10-15, 20-30, 30-40, and >100 yrs, respectively) were selected for the study of the plant species, vegetation features as well as soil physical & chemical properties in order to assess interaction between soil properties and vegetation structure. It was found that vegetation species had dry-resistant characteristics because of their extensive exposure to the basement rocks and thinness soil. Grass community was always coarse grass, shrub was generally dominated by vines, thorn bushes and tree species were almost leather-like, single and mini-type leaf plants. Factor analysis showed that the 3 factors, soil fertility, pH and clay, explain 67.97 % of total variance among the 19 soil property parameters. Soil fertility changed significantly effects included the increasing of soil organic matter, total and available nitrogen, humic acid, CEC, fuvic acid, exchange Ca, porosity and total P but decreasing bulk density. This trend was followed by enhancing of bio-enrichment capacity along the chronosequence of vegetation recovering process. Soil pH had no significant correlation with the vegetation recovery stages because it was determined by soil forming process and characteristic of parent materials. The factor clay only decreased slightly in the recovery stages. Cluster analysis indicated that vegetation structure could develop within short time under anthropocentric interfering, but soil fertility only accumulated with annual litter decomposing. We can conclude that recovery of vegetation community structure proceeded restoration of soil function.
Community Structures and Erosion Control Ability of Plantations in Xiaojiang Drainage Basin, China
Authors: Yang Ji Shan
Published: June 2012

Abstract: Xiaojiang drainage basin is one of the regions suffering from serious erosion and ecological degeneration due to the climate, geological and geomorphological conditions and the heavy human activities. Reforestation, which has been done since 1980s in the region, is an effective measure for the ecological restoration. Four types of plantations, i.e., Eucalyptus spp., Acacia mearnsii, Leucaena leucocephala and Pinus yunnanensis are investigated in the sample plots. Development processes and community structures of the tree layers, shrub layers and grass layers are studied with the “ergodic hypothesis” method and the index of species richness, coverage, importance value and Shannon_Wiener index et al, and erosion control abilities of the four types of plantations are compared in this paper. The result shows that the plantations of Acacia mearnsii and Leucaena leucocephala grow faster, which have higher crown coverages and stronger erosion control abilities than that of Pinus yunnanensis and Eucalyptus spp.. The Pinus yunnanensis plantation has a higher secondary understory biodiversity, the Eucalyptus spp. plantation has a high secondary understory biodiversity, but the plantations of Acacia mearnsii and Leucaena leucocephala have low secondary understory biodiversities. Study in this paper shows that the four types of plantation have distinct effects in promoting plant diversity and have different erosion control abilities. So plantation species selection and association mode should be considered in the process of reforestation for ecological restoration.
Potential Debris Flow Gully and its Discrimination — A Case Study in Wenchuan Earthquake Hit Areas
Authors: Chen Xing Zhang , You Yong , Liu Jin Feng
Published: June 2012

In this paper, we firstly defined the potential debris flow gully. And then using the data of different gullies in Wenchuan earthquake hit areas, we built a discrimination model of potential debris flow gully by Fisher Linear Discrimination Analysis method. Finally, the model was used to discriminate the gullies in Jinxihe catchment, in Anxian County. Potential debris flow gully is a kind of special gully which is in a special evolution phase of the gully when the gully has the happening possibilities of debris flow but no debris flow records. Because potential debris flow can often pose more serious disasters, discrimination of potential debris flow gully is important for disaster prevention and mitigation. To build discrimination model of potential debris flow gully, a database of different gullies in quake-hit areas was established and six discrimination indices were selected based on cause analysis of debris flow. Using the database and the six discrimination indices, we built the discrimination model by Fisher Linear Discrimination Analysis method. The discrimination model was used to discriminate the gullies in Jinxihe catchment. Discrimination results showed that the discrimination model was effective and feasible in discriminating potential debris flow gullies, but it still needs further revised and perfected.
Soil Physicochemical Properties of Cultivated Land in Different Farming Years in Korqin Sand Land
Authors: Wang Yong Fang , Bao Hui Juan , Hai Chun Xing , Bao Yin Shan
Published: June 2012

Naiman County is the typical area in Korqin sand land. Chose cultivated land in Naiman County, this article carried on comparative analysis for soil physicochemical properties of cultivated land in different farming years. This included change characteristics of soil physicochemical properties with different farming years in different slope positions (windward slope, sloping top and leeward slope) of cultivated land and quantitative analysis between farming years and soil physicochemical properties. The results showed that: (1) there were different changes in soil texture in different slope positions of cultivated land in different farming years: at first 15 years, in the windward slope, the soil texture emerged good trend year by year, but after 30 years of farming, the soil texture get significantly worse. In the sloping top and leeward slope, the soil texture was changed for the better trend along with the increase of farming years. (2)There were different changes in soil nutrients in different slope positions of cultivated land during different farming years: in the windward slope, farmed from 3 years to 15 years, upward trend showed among the most nutrients and until 30 years, it obviously reduced and drop back to level of the 3 years; There was a rising trend in the leeward part of the nutrients; sloping top was between the middle and more indicators decline in nutrient content than that of increasing. (3) There was relationship between the farming years and soil physicochemical properties: the effects on soil texture was higher than the soil nutrients and correlation between different slope positions was different: in the windward slope, farming years correlated positively with sand and available P and a negative correlation was found between farming years and other indicators. In the sloping top, farming years correlated negatively with sand, total N, total K, alkaline N and available P, correlated positively with other indicators. In the leeward slope, farming years correlated negatively only with sand and total K, correlated positively with all of other indicators.
Remediation of Decabrominated Diphenyl Ether Contaminated Soil Using White Rot Fungi
Authors: Wu Jun Qin , Zhao Yue Chun , Liu Lu , Fan Biao , Li Ming Hua
Published: June 2012

Biodegradation of decabrominated diphenyl ether (BDE-209) in soil by white rot fungi under various experimental conditions was investigated in this study. It was found that BDE-209 in soil could be rapidly and efficiently degraded by white rot fungi, and the biodegradation fits the pseudo-first-order kinetics during a 15-day incubation period. The residues of BDE-209 in soil decreased with the increase of amount of white rot fungi addition. It can be seen from the results that, white rot fungi have good ability on degradation with one-step or two-step addition method. In native soil, the degradation of BDE-209 reached 52.65%, which was higher than that in sterilized soil. About 37.76-53.74% of BDE-209 was degraded in different soil types after 15 days. In addition, it was confirmed in this study that the presence of Cu2+, Cd2+could enhance the remediation of BDE-209 contaminated soil, and the residues decreased by 69.20% and 54.65% for Cu2+and Cd2+treatment, respectively. However, the superior ability of white rot fungi to degrade BDE-209 was not obvious at low pollution level (≤0.5 mg kg-1).
Deformation Characteristics of a Preexisting Landslide in Reservoir Area during Reservoir Filling and Operation
Authors: Wei Jin Bing , Zheng Hong Chun
Published: June 2012

A monitoring system was implemented to monitor the hydrodynamic and deformation response of a preexisting landslide in the Three Gorges Reservoir area. The monitoring results indicate that the deformation is mainly caused by reservoir impounding and is mainly composed of the deformation of the slip band. The effect of reservoir level fluctuation on landslide stability mainly depend on two aspects, one is the change of shear stress and shear strength on the slip surface due to the change of slide body weight and pore water pressure, the other is seepage pressure.
Effects of Vegetation Cover on Runoff and Sediment in Field Prototype Slope by Experimental
Authors: Yang Chun Xia , Xiao Pei Qing , Zhen Bin , Shen Zhen Zhou , Li Li
Published: June 2012

The characteristics as well as the correlation between runoff and erosion was studied under 3 kinds of cover conditions of bare-slope, artificial grass slope and ecological-restoration slope with 20°slope gradient by runoff scouring intensities of 9l/min. The results showed that: (1) Sediment yield which sourced from artificial grass slope and ecological-restoration slope was separately decreased by 95% and 98% than bare slope, and the runoff reduced by 20% and 50% than bare slope respectively; The infiltration rates of the two kinds of grass slope were higher than the bare slope by 38.32% to 51.10% and 114%; (2) Sediment and runoff process showed that the stable state appeared respectively at 26min, 18min and 6min under bare slope, artificial grass slope and ecological-restoration slope, the amount of runoff was bare slope> artificial grass slope > ecological-restoration slope. (3) For bare slope and artificial grass slope, the relationship between sediment and runoff, sediment and the drag coefficient which both showed a negative correlation, but the correlation which from the ecological-restoration slope wasn’t obvious, so, further studies should carry out to promote runoff-sediment relations on ecological-restoration slope.
GIS-Based Landslide Susceptibility Analysis-Taking Middle and Upper Reaches of Nujiang River for Example
Authors: Wu Feng Qiang , Wang Wei Hong , Zuo San Sheng
Published: June 2012

65 landslides were interpreted from multi-source satellite image and investigation. And then, the seven factors that influence landslide susceptibility, including stratum, NDVI, faults, drainage, DEM, gradient and aspect were created in raster data format based on GIS and calculated the proportion of landslide disasters in each factors by its CF value using the certainty factor analysis method.
Improvement on the Method of Measuring Soil Saturated Hydraulic Conductivity by Using Permeating Bucket
Authors: Guo Feng Tai , Wu Sha , Cheng Dong Juan , Liu Ya Min
Published: June 2012

The method of measuring saturated soil hydraulic conductivity by using permeating bucket is easy and simple and the instrument is cheap. The water volume must be measuring for many times, meanwhile the water must be added on the top of permeating bucket to sustain the water layer thickness. Based on the principles of supplying water in the fixed water head by Marriott bottle, the method mentioned above is improved, which can reduce the experiment work and improve the experiment accuracy.
Monitoring Desertification Process in Songnen Sandy Land during the past 10 Years
Authors: Yang Wei , Zhang Shu Wen
Published: June 2012

In this paper, we used MODIS remote sensing image data of Songnen Sandy Land in July 2000 and 2010, extracted the value of MSAVI and vegetation cover index. Based on their values, degrees of desertification were classified including: un-desertification, micro-desertification, mild desertification, moderate desertification and severe desertification. The result show that the area of the desertification decreased in the past 10 years. The desertification is under a decreasing trend.
Soil Pore Space Fractal Dimensions Were Deduced Conversely by the Curve of Soil Water Retention
Authors: Hu Hao Yun , Li Zi Xiao , Hou Yi Kai , Liu Liang , Sun Jian Wei
Published: June 2012

The functional equations have been established between the soil water retention curve and the soil structures fractal dimension by fractal geometry theory. Based on the functional equations have the same or similar law form with Campbell law, Soil pore space fractal dimensions were deduced conversely by the curve of soil water retention, which not only reveal physics matter of Campbell law， but also can carry out fractal research of prediction of soil water retention. The comparison of predicted soil water retention with measured data shows that the proposed model can be used to describe various soil textures.
Study on the Plants Growth Effect of the Sediment-Laden Flow Turbulence Characteristics
Authors: Li Jun Ning , Yang Ju Rui , Luo Jing
Published: June 2012

Abstract: The effect on Sediment-laden flow turbulence characteristics of Wetland plants simulated by flexible plastic tree growing and distribution of suspended sediment concentration were studied through the flume experiment under a certain hydraulic condition. The experimental results showed that the vertical velocity distribution of sediment flow with plant was no longer consistent with logarithm distribution with no plants in sediment flow, but for the "S"-type distribution. The turbulent intensity and Reynolds stress in longitudinal,transversal and vertical orientation were anisotropic, and the maximum and the location of the maximum increased with increasing plant height. Plant growth effects of sediment removal was significant. The vertical suspended sediment concentration increased with plant height decrease, the suspended sediment concentration gradually decreased along the flow direction.
The Analysis on the Effect of Silt Arrester System Construction in Small Watershed Runoff Sediment and the Evaluation of the Ecological Environment
Authors: Ma An Li , Yin Bao Ku
Published: June 2012

The monitoring and evaluation on silt arrester system of small watersheds involves monitoring indicators, data collection, analysis and evaluation etc. The Yellow River Water Conservancy Committee carried out a "small watersheds of the Loess Plateau model project" from 2005 to 2010 in the Yellow River sandy area. The project has 12 small watershed silt arresters, one of which is in Yonghe county of Shanxi province. This article takes the work of sediment transport monitoring in Yonghe silt arrester system as an example and describes the monitoring method, content, and finally analyzes the influence of silt arrester system construction and sediment transport on ecological environment.
Absorption Ability of Different Tree Species to S, Cl and Heavy Metals in Urban Forest Ecosystem
Authors: Fan Zhi Ping , Wang Qiong , Li Fa Yun , Sun Xue Kai
Published: June 2012

Heavy metals and atmosphere pollutants that caused the soil pollution and low air quality are main environmental problems in cities which located in the industrialized regions. Different tree species in urban forest ecosystem have absorption ability to heavy metals in the soil and atmosphere pollutant and ameliorate environmental pollution. However, the influence of different tree species on the absorption ability of different pollutant is not yet clear, and this held up selection suitable tree species in urban forest plantations to improve urban environment. In the study we compered pollution absorption ability of 13 tree species in Shenyang, Northeast China. The results showed that, the adsorption capacity of different tree species on pollutants are different. The highest value of Cu was 9.32 mg kg-1 found in Berberisthumbergii cv. Atropurpurea, Zn was 51.461 mg kg-1 in Pinus bungeana, Pb was 7.459 mg kg-1 in Malus pumila Mill, Cr was 9.841 mg kg-1 in Buxus microphylla, S was 8916.07 mg kg-1 in Salix babylonica, Zn was 4678.388 mg kg-1 in Buxus microphylla. Pollutant concentrations in the same plant species are different in 3 different sample sites. This indicate the contaminated degree of 3 sample sites were different. In our study, Huigong square pollution degree is serious than the Beiling Park and Huishan ecological park. Significant correlation was found between Cu and Cr, Cu and Cl, S and Zn, Cr and Cl (P<0.01) and that between Cu and Zn, Cu and Pb at 0.05 level. The relationship between heavy metals and atmosphere pollutant (S and Cl) indicated that traffic activities could be one of the dominant roles of heavy metal and atmosphere pollution in Shenyang City.
Combine Empirical Equation with Experiment for Prediction of Soil Saturated Hydraulic Conductivity
Authors: Liu Yan Wei , Zhu Zhong Yuan
Published: June 2012

In order to improve simulation precision of saturated hydraulic conductivity, use RETC and PTFs function to simulate saturated hydraulic conductivity by measured research area surface soil (0-20cm) physicochemical property and soil texture data. The simulation results were assessed by the approach of consisting in presenting a graphical representation of model simulated compared with observed values and by mean square error. The main results indicate that the RETC-PTFs and local PTFs mean square errors are 1.19 and 0.40 respectively. The precision of RETC-PTFs is lower than local PTFs function obviously using soil physicochemical property and soil texture data. The RETC-PTFs is inappropriate to this area. Accuracy of each input data precision of RETC-PTFs play a big part in because of less data needed. More complete data not always get better simulating results.
Effect of Grass Coverage on the Sediment Concentration in Overland Flow
Authors: Li Mian , Yao Wen Yi , Yang Er , Ding Wen Feng , Chen Jiang Nan
Published: June 2012

By scouring experiments, the changeable process and characteristics of sediment concentration in sloping surface with different coverage degrees and spatial locations of grass were studied. Five grass coverage degrees of 0, 30%, 50%, 70%, 90%, three spatial locations of grass (upslope, mid-slope, low-slope) and two water inflow rates of 3.2L/min, 5.2L/min were applied to a 0.5 by 4 m soil bed in scouring experiments. Results showed that the sediment concentration in overland flow obviously decreased with increasing grass coverage degree during the scouring experiments. When the grass coverage degree is over 30%, the grass can play obvious role in reducing the sediment concentration, and along with the increase of grass coverage degree the role became more and more obvious, particularly when the grass coverage degree reached to 70%. The spatial location of grass on the sloping surface has little effect on the sediment concentration in overland flow.
Response of Greenhouse Gas Emissions to Nitrogen Deposition in Terrestrial Ecosystem
Authors: Meng Xiang Nan , Zhao Yu Sen , Zheng Lei , Ni Hong Wei
Published: June 2012

Nitrogen deposition input changes the carbon and nitrogen cycle rate significantly in terrestrial ecosystem, and then affects the structure and function of entire ecosystem. The elevated atmospheric concentration of greenhouse gases is one of the most important causes of global warming and has become an indisputable fact. Terrestrial ecosystem is the important source and sink of greenhouse gases, and plays an extremely important role in global warming. Nitrogen deposition can affect the fluxes of greenhouse gases from terrestrial ecosystem. The responses of greenhouse gases emissions to nitrogen deposition in forest ecosystem, farmland ecosystem, grassland ecosystem and wetland ecosystem of typical terrestrial ecosystem are reviewed in this paper. As a result of the differences of ecosystem types, climate, vegetational community and soil N status, the effect of nitrogen deposition on main greenhouse gases flux emissions present in three aspects: suppression, promotion and non-significant in terrestrial ecosystem.
Emissions Trading System and Supporting Policies under an Emissions Reduction Framework
Authors: Qiu Xiao Ming , Yang Jia Sheng
Published: June 2012

This paper, through building mathematical models, makes an analysis on the emissions trading system under an abatement framework. And the authors obtained four conclusions: (1) The impact by environmental taxes on the existing firms’ choices of optimal discharging amounts is uncertain, the existing firms’ discharging amounts will be on the decrease with the increased prices of emissions permits, and paid initial emissions allowances will reduce the existing firms’ profits; (2) Under an intertemporal trading system, the existing firms’ holding the permits conforms to the principle of profit maximization; (3) Under the intertemporal trading system, the prices for emissions permits for the entrant firms are always on the rise and so are their access costs into the industries, thus frustrating local governments’ efforts in attracting investments; and (4) Emissions reduction policies are good regulatory instruments for promoting local economic welfare and realizing sustainable development. The paper also gives some suggestions for triggering and activating the emissions trading system and formulating supportive policies.
Specific Death Symptoms and Organic Lesions of Blood Clam Tegillarca granosa in Acute Copper, Zinc, Lead and Cadmium Exposures
Authors: Liu Guang Xu , Chai Xue Liang , Shao Yan Qing , Wu Hong Xi
Published: June 2012

Blood clam, Tegillarca granosa, habit in near-shore muddy sediments facing increasing danger of heavy metal contamination. In order to assess the acute toxicity of heavy metals on T. granosa, short term lethal concentration (LC50) of copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd) were determined, symptoms of death and organic lesions were illustrated. With relative high LC50 values obtained, T. granosa showed great heavy metal tolerance indicates adaptations to habitat environment. T. granosa died in acute Cd exposure showed specific death symptom with foot extended outside of the tightly closed shells. In this study, different metals led to different organic lesions. Dark red erosive and inflamed gills were observed for T. granosa exposed to acute Cu and Pb, respectively. Inflamed gonad and foot, and contracted mantle were observed for Cd and Zn exposure trials, respectively. The results of this study may provide knowledge to assist in heavy metal pollution bio-monitoring and quick diagnosis of massive death incidence.
The Application of Fuzzy Comprehensive Evaluation Method in Non-Point Pollution on Wetland Water Environmental Impact
Authors: Ren Yi Bin , Li Ji Guang , Ren Nan Qi , Li Xiao Kun
Published: June 2012

To clear the agricultural non-point source effects on wetland water environment and the purification efficiency of wetland on non-point pollution. Use the fuzzy comprehensive evaluation method to analyze the water quality conditions of three different urban wetland of Harbin in north shore of Songhua river which affected by human Agriculture activities. Selected Wanbao wetland goose island and sun island water quality monitoring, monitoring time was in October 2004, May 2005, August 2005, and April 2008, a total of four times. The results shown that Wanbao wetland meets water quality planning V water, Goose Island and the sun island meets quality planning IV water. According to fuzzy coefficient can compare the three places wetland water pollution by heavy degree to light for Wanbao wetland > Sun island wetland > Goose island wetland. From upstream to downstream water purification by wetlands, water quality gradually improved.
An Ecological Dynamics Model of Algae Growth in Taihu Lake and the Analysis of its Influencing Factors
Authors: Liu Qing Quan , Gao Yong , Xu Xu Feng
Published: June 2012

For the study on the eutrophication problem in Taihu Lake of China, an ecological dynamics model of algae growth is established based on the simulation of the growth of the dominating algae in Taihu Lake. Chlorophyll-a (chl-a), total phosphorus (TP) and total nitrogen (TN) are chosen to be the water quality variables. The main factors influencing the algae growth in Taihu Lake are investigated by the sensitivity analysis of the model’s parameters. The results show that the maximum growth rate of algae, the algae respiration rate, the coefficients of temperature influence and the half saturation constant for phosphorus have significant influences on the simulation results. Temperature and TP are the dominating factors of influencing the algae growth in Taihu Lake.
Degradation Mechanism and Applicability of Irrigation Recovery Technique on Xilamuren Grassland, Inner Mongolia
Authors: Gao Tian Ming , Zhang Rui Qiang
Published: June 2012

Due to the drought climate and over grazing, the grassland degrades severely recently, which not only influences local environment, but also threatens ecology safety of northern areas. Urgently control of degraded grassland and prevent advanced deterioration are needed. Recently, irrigation plays vital role on the recovery of degraded grassland in northern pastoral areas. Different amount irrigation experiment (adequate and moderate irrigation) was carried out from 2007 to 2009 on Xilamuren Grassland, Inner Mongolia. The experiment plots vegetation quantitative characteristics were investigated during 2007～2011. Compared with no irrigation plot, it’s concluded that: ① Different irrigation amount have the same effect on improving the production and biodiversity during irrigation. ② When stopped irrigation, the production and biodiversity of the two ever irrigated plots degraded more and faster than the non irrigation plot equally. ③ Moderate irrigation can save more water while recovering degraded grassland satisfactorily. To keep stable, the irrigation amount and times should be decreased gradually.
Diffusion Model of Heavy Metal Loss in Mining Area and its High Efficient Prevention and Cure
Authors: Xu Feng Ying , Xu Yong Chun , Li Chang You
Published: June 2012

In order to high efficiently prevent and cure the diffusion of heavy metal loss in mining area, this paper investigated the main ways of heavy metal loss, built the diffusion model of its non-steady-state and uniform loss, and solved the model by integration, a time-varying function on the path of heavy metal loss which diffused into soil and runoff waters in the mine area was acquired, and a method of efficient prevention and cure was obtained. The results shows that the continuous existence of heavy metal in the mining area will aggravate and increase the regional pollution of soil and runoff waters, among them, the diffusion speed of heavy metal loss dissolved into runoff waters due to soil erosion in mining area will be faster and the hazard will be lager, there exists a high pollution concentration in the estuarine of new waters which the runoff flowed into. The effective recovery of heavy metal residue and waste liquid in mining area, and the decrease of discharge concentration is the important ways to effectively reduce the improvement costs of heavy metal pollution area and improve the harnessing effect, if further combing the restorations of engineering plants and bacteria improvement for heavy metal polluted area, which would be more efficient and rapid, and suitable for research and spread.
Gill Damage and Recovery in Juvenile Black Sea Bream Acanthopagrus schlegelii Stressed by Uncontaminated Suspended Solids
Authors: Li Yun , Shen Ang Lv
Published: June 2012

Studies on the responses of fish to suspended solids (SS) have focused on freshwater salmonid species, far less is about marine species. In this study, juveniles of black sea bream Acanthopagrus schlegelii were exposed continuously to various concentrations of uncontaminated SS for 10 days to detect gill damage, and then returned to clean seawater without SS for 10 days to detect gill recovery. The results showed that, no clear changes in chloride cells, Na+-K+-ATPase activity and DNA damage parameters (comet cell rate, tail length and tail moment) were observed after 10 days of exposure to 100 mg SS/L, while at 1000 mg SS/L these paramaters were significantly altered. After the 1000 mg/L SS-treated fish were transferred from water containing SS to clean seawater only, Na+-K+-ATPase activity, tail length and tail moment all indicated signs of recovery, but these kinds of recoveries were incomplete and did not return to the control levels. The rapid response and recovery observed in our study show that high concentration uncontaminated SS can induce gill damage of juveniles of A. schlegelii, and this kind of damage is difficult to recover completely.
Research Advance in Soil Organic Carbon Change
Authors: Xie Zhen Hong , Fu Bo , Liu Xiang
Published: June 2012

Changes of soil organic carbon storage play an important role in carbon balance in the world. Firstly, analyzed the effect factors of the soil organic carbon changes that are limited to qualitative research instead of quantitative studies, and the main effect factors are climate and soil properties , but so far it is still unclear how the temperature changes affect soil organic carbon dynamical changes; then, summarized estimation methods of soil organic carbon storage, and the soil type method is more commonly used estimation method of soil carbon storage in china and abroad for simple method and the data easily accessible, and the study on soil organic carbon storage is static based on a point in time and is lack in dynamics analysis, therefore it is to be solved how to improve the estimation accuracy of soil carbon storage in the future; finally,summarized soil carbon cycle model at home and abroad, and it is a key point that the soil carbon cycle models combined with GIS and RS simulate large-scale soil carbon cycle in the future.
The Application of Costs and Benefits Analysis in Coastal Land-Reclamation
Authors: He Yue Yun , Xue Xiong Zhi , Kong Hao
Published: June 2012

Today, the coastal areas of the world amounting to nearly 10% of the total world’s land area, supports nearly half of the world’s human population. This causes serious population pressure and environmental problems. To reduce the pressure of land scarcity, cities along the coastal land are now paying their attention to land reclamation. Although land reclamation results in significant benefits to the coastal cities, it simultaneously causes serious environmental problems. Therefore, satisfactory management of reclaimed land is a big challenge which governments are now facing. Based on economics, this article presents some economic means to efficiently manage coastal areas. Integrating the costs-benefits analysis and input-output table, this paper builds the “costs-benefits analysis system”, and provides the models of estimating the value of some main aspects of the costs. Through outcome consult method, shadow price, TCM (Travel Cost Method), CVM (Contingent Valuation Method) and other methods, one can appraise the ecological damage in monetary terms, which allows to transform questions of “yes” or “no” into questions of “more” or “less”, one can easily judge the feasibility of this project in terms of social benefits. Using this costs-benefits analysis system to assess the land reclamation in Gulei port, Zhangzhou, China, the outcome showed that the total costs were almost 3.4 times more than the benefits, meaning that it is really not beneficial to construct the project from economics point of view.
Building Long-Term and Consistent Vegetation Index Based on Association Analysis between Different VI Products
Authors: Sha Zong Yao , Bai Yong Fei
Published: June 2012

The dynamics of vegetation cover plays an important role in global environment evaluation. Due to the spatial, spectral and radiometric differences among different remote sensing platforms, building long-term and consistent vegetation index (VI) time series is desired to derive comparable vegetation health. In this paper, an approach called Min_Max stretch transformation (MMST) was proposed to generate long-term and consistent VI series based on spatio-temporal association analysis between AVHRR NDVI and MODIS EVI. The proposed approach intended to map AVHRR NDVI to MODIS EVI level and thus both VI products provided consistent VI series. The consistency of the transformed dataset was further evaluated.
Palm Species on the Application of Landscape Garden in Hainan
Authors: Guo Yi Ni , Zhang Yan , Huang Ye
Published: June 2012

Palm plants are important garden plant resources, in the landscape has many USES. Based on the observation of the landscape of hainan palm, palm plants in hainan explore into the main application of way and configuration types, and points out that the palm species of plant landscape in hainan shortage, and puts forward personal advice.
Technical Study on Relationship between Terpene Phenolic Compounds and Health
Authors: Jia Yong Hui
Published: June 2012

The hydroxy derivatives of aromatic hydrocarbons which have hydroxyl getup directly attached to the ring are called phenols. Small amounts of water dissolved in phenol lower the melting point to below the room temperature. This paper summarized the bioactivities and safety issues of Terpene Phenolic, and its functions, biosynthetic mechanisms, characteristics and clearing strategies of terpene phenolic compounds.
Soil C:N:P Stoichiometry across Forest Communities in Eastern Guangdong, China
Authors: Li Jing Peng , Sun Dong , Su Zhi Yao
Published: June 2012

Stoichiometric characteristics of soil organic carbon (SOC), total nitrogen (N) and total phosphorus (P) across forest communities were investigated based on community classification in Changtan Nature Reserve, Guangdong province, China. Results are as follows: (1) the monsoon broadleaved forest had high concentrations of SOC, N and P as compared with other community types. The highest concentration of SOC (39.2±2.3 g•kg-1) was found in the Schima superba community, while the highest concentration of N (2.21±0.24 g•kg-1) occurred in the Castanopsis fissa community, which also had the highest P concentration. Pinus massoniana community had the lowest concentrations of SOC, N, and P, especially lacking in P element. (2) Communities which had longer succession time exhibited a high C:P ratio. The Schima superba and Castanopsis fissa communities had the highest C:P ratios (301.0 and 304.2, respectively); in contrast, soil C:P ratio in the Cunninghamia lanceolata community was only 150.0. (3) The highest and lowest ratios of soil C:N were found in monsoon evergreen broadleaved forest (36.6) and Schima superba community (17.0), respectively, which was significantly different (P < 0.05). No significant difference was found in the N:P ratios among the five communities.
The Effect of Cadmium on Low Moleculer Weight Organic Acids Exudation of Triticum aestivum L.
Authors: Bao Tong , Sun Li Na , Tao Shi Bo
Published: June 2012

The influence of Cadmium(Cd) on exudation of low molecular weight organic acids (LMWOAs) were investigated based on the hydroponic culture experiment. Tartaric, citric, malic, and acetic acids were chosen as representatives of LMWOAs commonly present in roots exudation. We investigated the Cadmium accumulation in Triticum aestivum L.. The results showed that under the different levels of Cd, the exudation of four organic acids by roots had the different change trend. The concentrations of four organic acids in roots exudation were in the same following sequence tartaric>citric>malic>acetic. And the content of Cd in plants increased with increasing Cd concentrations. We found that at first some LMWOAs increased at low Cd treatments, we guessed that it was a normal reaction to the Cd treatment.
The Mechanism of Bud Dormancy in Plants
Authors: Zhang Li , Jia Feng , Wang Jin Shui
Published: June 2012

The seasonal cycling between growth and dormancy has received little attention despite its importance for plant behaviour. Many factors are involved in dormancy regulation, which include environmental factors, such as phytohormones, photoperiod and temperature. In this review, we reconsider seasonal cycles of growth and dormancy in view of dormancy within the meristem, together with recent exciting developments of phytohormones and epigenetic in the study of plants.
Current Situation and Development Prospect of Tung Oil Tree (Vernicia fordii) in Chongqing Three Gorges Reservoir Area
Authors: Xiong Xing Zheng , Liu Yun , Huang Xiao Hui , Wang Xiao Xue , Chen Yang , Yin Xiao Hua
Published: June 2012

In Chongqing Three Gorges Reservoir Area (TGRAC), the natural conditions of production of Tung oil tree (Vernicia fordii) are advantageous. It has an abundant cultivated varieties resource, a long history of cultivation, and is World-renowned by its excellent quality of oil. After 1990s, Tung oil production is gradually shrinking, a large number of Tung oil trees resources had been destroyed, Due to the excessive use of fossil fuels in today's world, however, there have been the deterioration of the environment and energy crisis. So clean and green biomass energy sources are favored. This paper introduces the resource status and distribution area of Tung oil trees, analyzes the planting advantages and development prospects of Tung oil trees, and provides suggestion on the development of the Tung oil trees industry in the TGRAC.
Effect of UV-B Radiation on GSH and GSH-Related Enzymes of Brown Alga Sargassum thunbergii (Mert.) O.Kuntze
Authors: Li Li Xia , Zhao Ji Qiang , Tang Xue Xi
Published: June 2012

The effect of UV-B radiation on activities of the glutathione reductase (GR), glutathione peroxidase (GPx), glutathione S-transferases (GST) and GSH content in Sargassum thunbergii, an intertidal macroalgae, were analyzed. While GR and GPx activities were relative stable in a low dosage of UV-B radiation (Luv), they decreased significantly under high dosage of UV-B radiation (Huv) with prolonged exposure. However, the activity of GST in Huv treatment did not decrease obviously in comparison with that of the control. GSH content increased rapidly under Luv and a medium dosage of UV-B radiation (Muv) with moderate exposure in the early stage. H2O2 and TBARS accumulated rapidly, particularly for Muv and Huv treatments. These data indicate that S. thunbergii lacks tolerance to relatively higher dose of UV-B stress, although GSH-related enzymes may play certain role against UV-B induced oxidative damage.
Gas Exchange Characters with SO2 Fumigation of Different Concentration and Time in Soybean
Authors: Li Jing , Jiang Da Long , Li Xiao Ming
Published: June 2012

The low concentration of SO2 in the air can promote stomata opening of plants and improving plant photosynthetic rate, but the gradual accumulation of SO2 on plant leaves can convert the chlorophyll into phaeophytin, which has no photosynthetic activity, and then affect the plant growth and crop production. After Fumigation with SO2 in soybean under several different concentrations (4 µl/l,10 µl/l,20 µl/l,40 µl/l) and time spans(1h,2h,4h) respectively, the photosynthesis and gas exchange characteristics were determined. The experimental data showed: (1) with the increasing of concentration and time for fumigation, SO2 had a great adverse effect on photosynthesis in soybean. Such as the light saturation point of plants decreased, the light compensation point increased, and the maximum net photosynthetic rate reduced significantly (e.g., fumigation with SO2,4-40 µl/l-4 h, Anmax reduced 29.5% to control) compared with the control plants’. (2)After all kinds processing time, low concentration of fumigation (4µl/l) caused larger stomatal conductance than control. However, the other treatments caused smaller gs than control. (3)gs revealed significant positive correlation with transpiration rate(E), each treatment and control shows r ≥0.9,P2. (5)Concentration of chlorophyll was no insignificant differences with the control at different treatments. After fumigation, the range of chlorophyll a / b was 1.39~1.61 and there was no big difference from control (chlorophyll a / b is 1.49), except the treatment of 20µl/l-1h, which had a significant decline in chlorophyll b (chlorophyll a / b is 1.71).Results: (1) SO2 concentration had greater impact on soybean than time of fumigation, and the impact of high concentration in short time on soybean was obviously significant. (2) SO2 fumigation in short time and low concentration can promote stomata open, however SO2 also can damage the photosynthetic activity of chlorophyll. After a long time of fumigation, photosynthetic rate decreased rapidly, even if gs increased.
Heterotrophic Fed-Batch Cultures of Nostoc flagelliforme and Production of Extracellular Polysaccharides
Authors: Jia Shi Ru , Ding Zhen , Tan Ning , Wang Nan , Han Pei Pei , Yuan Nan Nan
Published: June 2012

Nostoc flagelliforme is a kind of terrestrial cyanobacterium with high economic value. Dissociated cells, which separated from a natural colony of N. flagelliforme, could be cultivated heterotrophically in the darkness on xylose and glucose under fed-batch culture conditions. Growth and extracellular polysaccharides (EPS) production in different cultures are investigated. At harvest time, the cultures contain 1.215 g•L-1 of biomass and 122.5 mg•L-1 of EPS respectively. The gravimetric EPS production rate is 17.5 mg•g-1•day-1, which is 1.65 times higher than previously reported results for heterotrophic Nostoc flagelliforme grown on xylose batch culture.
Induction of Maize Glutathione S-Transferase by Herbicide Safener and their Effect on Enzyme Activity against Chlorsulfuron
Authors: Zhao Li Xia , Liu Cheng Guo , Fu Ying , Xing Zhi Yong , Ye Fei , Gao Shuang
Published: June 2012

The acetolactate synthase(ALS) activity, glutathione S-transferase(GST) activity and glutathione(GSH) content in maize was investigated in response to treatments with safener (S)-3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine. When induced by the chiral compound, the GSH content in root and shoot of maize increased 91.10% and 71.66%, respectively, the recovery rate of ALS activity reached 77%, and the GST activity increased 103.77%. The activity of maize GST was also assayed towards chlorsulfuron in vitro; the results showed that the induction of GST activity against chlorsulfuron of 14.54% was obtained. The enhancement of GST activity was found to be concomitant with changes in kinetic constants, which was related directly to the enzyme affinity for the CDNB substrate.
The Effect of Different Drought Stress on Antioxidant Enzymes and Lipid Peroxidation on Zoysia japonica
Authors: Chen Zhong Lin , Xu Su Nan , Li Yue , Xie Shi , Fan Li Xia , Zhang Li Hong
Published: June 2012

The objective of this study was to understand the effects of mild, moderate and severe drought stress on zoysiagrass(Zoysia japonica). Superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT), and malondialdehyde (MDA) content were investigated. Mild drought(60%-70% of field capacity), moderate drought(45%-55% of field capacity), and severe drought (25%-35% of field capacity) were remained for 16 days. A gradual increase was observed in SOD activity of Zoysiagrass from 1 to13 days of drought stress in all treatments. POD and CAT activity, and lipid peroxidation increased in all treatments, and maximum change was happened in severe drought group. Severe drought has more serious damage to Zoysia japonica than mild drought and moderate drough. This suggests that Zoysiagrass has excellent drought tolerance and its ability to survive in the drought environment is very strong.
The Uptake Kinetics of Nitrogen and Phosphorus by Nitzschia Sp.
Authors: Su Qun , Xing Rong Lian , Wang Hui Yi
Published: June 2012

The effects of eutrophication on the absorption kinetic parameters of nitrogen and phosphorus are investigated. The results show that the kinetic characteristics of phosphate, nitrate- nitrogen, ammonia-nitrogen and nitrite-nitrogen of Nitzschia sp. are all generally in accord with the function of Michaelis-Menten equation. The Km of them are 1.81 mg/L, 1.75 mg/L, 0.20 mg/L and 4.53 mg/L, respectively. The maximum uptake rates of nitrate-nitrogen and ammonia- nitrogen are higher than that of nitrite-nitrogen, which indicates that nitrate-nitrogen and ammonia- nitrogen can be uptaken more preferential than that of nitrite-nitrogen. In conclusion, Nitzschia sp. has a fast utilized rate of ammonia-nitrogen, nitrate-nitrogen and phosphorus. This indicates that Nitzschia sp. has a good effect on water quality and it could be applied potentially to purify waste water.
Antioxidant Activity In Vitro of Selenium Polysaccharide of Thlaspi caerulescens L. Rich in Selenium
Authors: Zhang Chi , Liu Xing Ping
Published: June 2012

The antioxidant capacity of the human body is closely related to its ability of disease resistance and anti-aging. It is a current research focus to find effective anti-oxidants used in medicine, food, health care, beauty make-up from natural plants. In this paper, we studied the content of selenium in selenium polysaccharide and its antioxidant activity in vitro of Thlaspi caerulescens L. produced from Yutangba of Enshi selenium mining area. The double tracts atomic fluorescence spectrometry is used to detect the total selenium content in the sample and that of selenium polysaccharide in the active ingredient of the sample. The salicylic acid method and pyrogallol autoxidation method are used to detect the scavenging activity of selenium polysaccharide on hydroxyl radicals and superoxide anion. Experiments show that the total amount of selenium in Thlaspi caerulescens L. is 708ug.g-1, while the amount of selenium in selenium polysaccharide is 98.1ug.g-1, accounting 13.86% of the total selenium content. Meanwhile, selenium polysaccharide in samples is with significant antioxidant capacity, and it shows a certain dose-effect relationship. Selenium polysaccharide has stronger anti-oxidation ability than pure polysaccharide compared with non-selenium polysaccharide. Therefore, plants rich in selenium are better natural antioxidants. This study will provide the necessary experimental basis for the effective and rational development and utilization of Thlaspi caerulescens L. rich in selenium
Clone, Expression, and Purification of a Hyperthermophilic Endoglucanase Gene Cel12B from Thermotoga maritima
Authors: Shi Hao , Li Xun , Li Xiang Qian , Wang Fei
Published: June 2012

The thermostability and catalytic activity of endoglucanase from thermophilic Thermotoga maritima were improved by evolutionary molecular engineering. The cel12B gene from Thermotoga maritima was cloned and expressed, and the expressed Cel12B protein was purified by His-tag affinity chromatography. The constructed plasmids were screened on LB plate with ampicillin using Escherichia coli BL21 (DE3) as a host. The results showed that both the enzyme activity and yield of the Cell12B protein expressed in pET15b-cel12B were 2 times as that of the protein expressed in pET20b-cel12B.