Loading...

Table of Content

Volume 17 Issue 2
10 May 2001
muci
Protecting Eco-Environment and Developing Organic Farming
GAO Zhen-Ning
2001, 17(2):  1-4. 
Abstract ( 1121 )   PDF (65KB) ( 3108 )  
Related Articles | Metrics
The necessity of developing organic farming and organic food in China has been described.The urgent in need,the advantages and the bright future of developing organic food industry in China have also been indicated.Some conceptual and attitudinal problems that need to be solved in this issue were pointed out. 
Development of West China and the Construction of Settlement Ecology—Take the Southwest Mountainous Area of China as an Example
CHEN Guo-Jie
2001, 17(2):  5-8. 
Abstract ( 600 )   PDF (65KB) ( 1645 )  
Related Articles | Metrics
Deterioration of the ecology and environment in West China is largely imputed to the backward mode of production and way of life widespread in the rural areas.In developing West China,construction of ecology should be integrated with the construction of human settlement in planning and implementation simultaneously.Emphasis should be paid on the issues of environmentally degraded habitation,endemic stricken habitation,habitation in nature reserves,nomadic habitation and project resettlement habitation.According to different ecological conditions,different strategies are to be taken,such as construction of new habitation,and rebuilding or resettling of habitation etc. 
Effect of Human Disturbance Intensity on Characteristics of Village-level Landscape Structure
HE Nian-Peng, ZHOU Dao-Wei, SUN Gang, WU Ling
2001, 17(2):  9-12,21. 
Abstract ( 655 )   PDF (100KB) ( 1336 )  
Related Articles | Metrics
With the distance from the research site to the center of a village as index for grading human disturbance intensity,the village could be divided into three zones,center,transition and base,different in human disturbance intensity,severe,moderate and light,respectively.Analysis was conducted of the relationship between human disturbance intensity and village level landscape characteristics.Results showed that they were closely related.With rise in intensity,the diversity index,relative abundance index and evenness index increased correspondingly,but stayed at peak and dominance index,however,fell to the bottom when the human disturbance was moderate in intensity.With increasing disturbance,the fractal value of landscapes in close relation to human life was getting less,but the similarity of landscape patches enhanced.
Characteristics and Protection of Wetlands in Shanxi Province
ZHANG Feng, SHANG Guan-Tie-Liang
2001, 17(2):  13-16. 
Abstract ( 595 )   PDF (84KB) ( 1668 )  
Related Articles | Metrics
Based on the basic environmental characteristics of the wetland resources in Shanxi and the existing problems,solutions as to how to scientifically protect and exploit the wetland ecosystems in Shanxi are put forth. 
Ecology of Shrub Vegetation in the Hexi Corridor
JIN Zi-Xue
2001, 17(2):  17-21. 
Abstract ( 611 )   PDF (102KB) ( 1714 )  
Related Articles | Metrics
On the basis of the basic principles of ecology,the shrub vegetation in the Hexi Corridor was classified into eight types,of which distribution,ecological characters,ecological significance and relations with soil were studied,with emphasis on their roles in improving the eco environment of the Hexi Corridor,in breaking winds,fixing sands,establishing desert grasslands and controlling desertification in the arid desert system.On such a basis constructive strategies are put forward for rebuilding ecology in desert system and sustainable development of the Hexi Corridor.
Biological Effect of Mulching on Upland Rice and Characteristics of N Absorption of Mulched Rice
SHI Ying, SONG Jin, SHEN Qi-Rong, XU Guo-Hua, LI Wei
2001, 17(2):  22-25,44. 
Abstract ( 676 )   PDF (102KB) ( 1542 )  
Related Articles | Metrics
Field experiments were carried out on upland rice mulched with semi decomposed rice straws,horsebean stems,plastic film,paper film or raw rice straws to study their respective effect on N absorption of the crop.In the experiment comparison was also made between paddy rice and upland rice in yield,yield components and utilization efficiency of irrigation water.It was found that the upland rice was higher than the paddy rice in N content in almost every organ.In the upland rice N absorption and accumulation occurred mainly after the jointing stage,whereas in paddy rice the absorption of large amount of N started right after transplantation and then little N was absorbed after the filling stage.The highest yield of upland rice was found in the treatment with semi decomposed rice straws as mulching,reaching 8 415 kg/hm 2,but its water consumption was only 7 14% of that of the paddy rice,about 12 times as high in water use efficiency.
Intraspecific Differences in Morphological Response of 20 Wheat Cultivars to Enhanced UV-B Radiation
CHEN Jian-Jun, ZU Yan-Qun, CHEN Hai-Yan, LI Yuan
2001, 17(2):  26-29. 
Abstract ( 628 )   PDF (111KB) ( 1763 )  
Related Articles | Metrics
Differences in morphological response of 20 wheat cultivars to enhanced ultraviolet radiation(UV-B,280~315 nm) were investigated under field conditions. Results showed that differences were observed in LAI,plant height, internode length and stem diameter between the cultivars. The responses of the cultivars in plant height and internode length were consistent and in significant positive relationship. Based on morphological response index(MRI),tolerant cultivars (MRI>-8 5) include Liaochun 9>Wenmai 3>Dali 905>Lanzhou 80101>Mianyang 26>YV 97-31>Bi 90-5,and sensitive cultivars(MRI<-49 4) include Huining 18>Fan 19>Chuxiong 8807>My 94-9>Qian 14> Yunmai 39>Longchun 16. Smaller angles of spread of leaves of the tolerant cultivars and wider angles of the sensitive cultivars were observed.Effect of UV-B radiation inhibiting incidence of stripe rust disease on wheat was also discovered. 
Effect of Cd2+ on Antioxidase System and Ultrastructure of Ottelia alismoides (L.)Pers. Leaves
XU Qin-Song, SHI Guo-Xin, DU Kai-He
2001, 17(2):  30-34. 
Abstract ( 679 )   PDF (177KB) ( 2216 )  
Related Articles | Metrics
Investigation was made of effect of simulated Cd 2+ pollution on the antioxidase system and ultrastructure of the cells of Ottelia alismoides(L.)Pers.leaves,mainly chloroplasts,mitochondria and cell nucleus. It was found that with increase in the stress,superoxide dismutase(SOD)activity and soluble protein content decreased drastically,while malonyl(MDA)increased;and that the activity of peroxidase(POD)and catalase(CAT)peaked at 0 1mg/L of the pollutant and declined afterwards. Electronic microscopic observation showed that at the early stage of the toxication,chloroplasts and mitochondria were swelling up;and thylakoids vacuolized apparently. Higher concentration of Cd 2+ aggravated the damage,making chloroplast membranes disappear and chloroplasts disintegrate,mitochondrion mesenchyme dissolve and mitochondria be on the verge of disorganization,and nucleolus chromatin agglutinate and merge into cytoplasm. Cd 2+ pollution not only destroys the plant’s antioxidase system,but also causes irreversible damage to its ultrastructure,thus leading the cells to death. 
Effect of Soils Polluted by Different Heavy Metal Sources on Rice
CHEN Huai-Man, ZHENG Chun-Rong, WANG Shen-Qiang, TU Cong
2001, 17(2):  35-40. 
Abstract ( 667 )   PDF (137KB) ( 2090 )  
Related Articles | Metrics
Effects of different pollution sources,simulated with different carriers of heavy metals such as contaminated soil,mine tailings,and sewage sludge,on growth of rice and transfer of nutrients and heavy metals in the soil paddy rice(Oryza sativa L.) system were studied with pot experiment in greenhouse. Results showed that effects on plant growth varied with sources and were in the order of contaminated soil>mine tailings>sewage sludge>tailing+sewage sludge. The concentrations of Cu,Zn,Pb and Cd were higher in the plants growing in soil treated with contaminated soil due to higher extractability and toxicity of the heavy metals therein. Rice growing in the soil applied with sewage sludge and tailing+sludge had lower concentrations of Zn,Pb and Cd because of lower extractability and bioavailability of the heavy metals,which might get complexed with organic matter in the sewage sludge. Meanwhile plant growth was also related to nutrient uptake of the plants. It was also demonstrated that by adding chemical agents into soil to determine heavy metal loading capacity of the soil was feasible and safe,for under lab conditions response of the test plants would be the most apparent. 
Ecological Effect of Cd Pb Combined Pollution on Soil-Rice System
WANG Xin, LIANG Ren-Lu, ZHOU Qi-Xing
2001, 17(2):  41-44. 
Abstract ( 696 )   PDF (94KB) ( 1875 )  
Related Articles | Metrics
Pot experiments were conducted to study laws of the migration and accumulation of heavy metals in the soil rice system and their ecological effect on the system. Results show that in treatment Cd Pb the crop was 5~7 cm shorter in plant height and 20% less in yield than that in CK. Normal growth of the crops in treatment Cd Pb and treatment Cd Pb Cu Zn As was seriously affected.In terms of distribution of heavy metals in grains,the treatments were in the order of treatment Cd Pb Cu Zn As>treatment Cd Pb>treatment single element.In treatment Cd Pb the presence of Pb stimulates the plant to absorb Cd,whereas the presence of Cd inhibits the absorption of Pb by rice.Cd is more mobile than Pb and likely to migrate upwards while Pb tends to accumulate in the root of rice.
Principles and General Risk Assessment Model for the Environmental Release of Transgenic Organisms
WANG Chang-Yong, CHEN Liang-Yan
2001, 17(2):  45-49. 
Abstract ( 675 )   PDF (114KB) ( 2110 )  
Related Articles | Metrics
Risk assessment constitutes an important part in legally controlling of environmental release of transgenic organisms and is a core subject in biosafety research. The paper dealt with the description of the principles and general risk assessment model for the environmental release of transgenic organisms on the basis of analysing and comparing the various methods on risk assessment, in combination with the past research results of the authors. The model includes three stages from hazard identification, risk estimate through risk evaluation, which can be divided into seven steps.
Effect of Combined Pollution of Aluminium(Al3+) and Cationic Surfactant(CTAB) on Maize Seedlings
SHU Liang-Zuo, ZHU Yu-Xiao
2001, 17(2):  50-52,55. 
Abstract ( 621 )   PDF (114KB) ( 1684 )  
Related Articles | Metrics
The effects of the co existing of cetyltrimethylammonium bromide(CTAB),a kind of cationic surfactant and Aluminium(Al 3+ ) on maize seedlings were studied.The results showed that CTAB could intensify the toxic effect of Aluminium on maize seedlings.The activities of protective enzymes,such as superoxide dismutase(SOD) and peroxidase(POD),increasing gradually,but activities of catalase(CAT) decreased,the generating rate of superoxide ions increased markedly,and so did membrane lipid peroxidation and plasma membrane permeability of the maize seedlings,however,the content of chlorophyll decreased.When the concentration of CTAB reached 1 0 cmc(critical micelle concentration),the photosynthesis rate and transpiration rate of the seedling dropped drastically.
Effect of Low-Molecule Organic Acids on Soil Adsorption of Fluoride
CHEN Jing-Kui, YU Qun-Ying, LU Hong-Xia
2001, 17(2):  53-55. 
Abstract ( 599 )   PDF (84KB) ( 1573 )  
Related Articles | Metrics
With the isothermal balance adsorption method,effect of citric acid and oxalic acid on fluoride adsorption by shajiang black soil and fluvio aquic soil was investigated and their possible mechanism verified.The results showed that the effect was significant.(1)When the concentration of the organic acid was low,soil adsorption of fluoride rose with the concentration of the organic acid,and when the concentration of organic acids was high,it dropped with rise in the concentration,and (2)in the presence of the organic acids,soil adsorption of fluoride showed an extremely significant linear positive (or negative) correlationship with balanced fluoride concentration in the soil. 
Environmental Policies for and Environment Management Capacity Building in West China
QIAN Xing-Fu, YE Ya-Ping
2001, 17(2):  56-58. 
Abstract ( 573 )   PDF (60KB) ( 1347 )  
Related Articles | Metrics
To expedite implementation of the strategy for rapid and sustainable development of West China,studies were conducted on environmental policy framework for and environment management capacity building in West China.On such a basis,some useful proposals were put forward.
Application of Statistical Methods in Identifying Environment-Affecting Factors
NAN Zhong-Ren , LI Ji-Jun
2001, 17(2):  59-63. 
Abstract ( 574 )   PDF (114KB) ( 1571 )  
Related Articles | Metrics
Functions of the correlative analysis,multiple linear regression method and stepwise regression method in identifying environment affecting factors were compared.With Baiyin City of Gansu Province as an example for analysis,the three methods were used to identify environment affecting factors of heavy metal pollution of the soil crop system in the suburbs of the city.Based on results of the experiment,indexes were proposed for selecting plans for remedying contaminated soils in the region under research.