Research Progress on Distribution,Sources and Ecological Effects of Phthalate in Soil

Phthalate esters(PAEs)are widely used as main plasticizers in plastic products,agricultural regulators,toys,and other fields.This paper reviewed the research progress on the distribution,sources,and ecological effects of PAEs.The effects of PAEs on soil microorganisms,animals,plants and soil properties were explored in sequence,providing effective theoretical basis for future research on PAEs.

Ecological Effects of Land Use Patterns in Red Soil HillyRegion

Plant biomass and biodiversity, element accumulation and return, water loss and soil erosion, and changesin soil properties were studied for up to 10 years after conversion of sparse tree-shrubby grass land into thefollowing four land use patterns: masson pine (Pznvs massonzana Lamb.) land, beautiful sweetgum (Ltq-uidambar fomosana Hance) land, vegetation reservation land, and artificial mowing land. The annualbiomass production of the masson pine land was 5060 kg ha￣-1 being 4.9, 2.1, and 6.0 times that of the beau-tiful sweetgum land, the vegetation reservation land, and the artificial mowing land, respectively. Comparedwith the background values, the number of plant species for the vegetation reservation land increased by 10species after 10 years of land utilization, while for the masson pine and the beautiful sweetgum decreased by4, and for the artificial mowing land by 9. For masson pine land, total amount of N, P, K, Ca, and Mg neededfor producing 1000 kg dry matter was only 3.5 kg, annual element return through litter was 22 kg ha￣-1, bothof which were much lower than those of the other patterns. Vegetation reservation was an effective measureto conserve soil and water and improve soil fertility in the red soil hilly region. Artificial mowing arousedserious degradation of vegetation and soil. Some measures and suggestions for management and exploitationof the red soil hilly region such as masson pine planting, closing hills for afforestation, and stereo-agricultureon one hill are proposed.

Ecological effects of crude oil residues on the functional diversity of soil microorganisms in three weed rhizospheres

Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion （Taraxacum officinale）, jerusalem artichoke （Silphiurn perfoliatum L.） and evening primrose （A colypha australis L.） rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units （CFUs） in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke （S. perfoliatum） rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant （p〉0.05） difference in the Shannon＇s diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.

Land use change and its ecological effect in Qian’an County of Jilin Province

Based on GIS and statistical methods, with the help of searching historical literatures and calculating the landscape indices, the land use changes of Qian'an County in both spatial and temporal aspects from 1945 to 1996 has been analyzed in this paper. And the driving forces of land use changes and their ecological effects are discussed too. The main findings of this study are as follows: (1) Land use changed greatly in Qian'an during 1945-1996, characterized by a decrease in grassland, wetland and water bodies, and an increase in cultivated land, saline-alkali land, and the land for housing and other construction purposes. Grassland decreased by 175,828.66 ha, and cultivated land increased by 102,137.23 ha over the half century. Accordingly, the main landscape type changed from a steppe landscape to a managed agricultural ecosystem. (2) Results of correlation analysis show that the land use change in the study area was mainly driven by the socioeconomic factors. (3) The ecological effects of land use change in the area are characterized by serious salinization, degression of soil fertility and the weakening of landscape suitability.

Ecological effects of the microbial weathering of silicate minerals

1 Introduction Global climate change is one of the greatest challenges facing humankind in the 21st century.Studying,and utilising,the carbon sink caused by the weathering of silicate minerals has been a key research focus for

Simulation Experiments of Land Surface Physical Processes and Ecological Effect over Different Underlying Surface

Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth's surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas...

Investigation and Assessment of Ecological Effect of Garden Plants in Linzhi, Tibet

In this study, we investigated main garden plants and assessed the eco- logical effect of garden plants in Bayi town, Linzhi district, Tibet. There are 33 land- scape plants, including 13 trees and 20 shrubs. There are 26 newly-introduced landscape plants, including 10 trees and 16 shrubs. The main landscape plants in Bayi Town could absorb 245.6 t of CO2 and release 178.66 t of 02 per year, illus- trating significant ecological effect. According to the theory that 25 m2 of lawn or 10 m2 of tree could completely absorb the CO2 breathed out by one person daily, the current green space in Bayi town could satisfy the requirement of 43 400 people. We also found that the maximum amount of retained dust by the garden plants is 12.8 t per year, which is considerable and consistent with the results from other studies.

Analysis of ecological effects of comprehensive treatment in the Tarim River Basin using remote sensing data

Based on multi-type,multi-temporal remote sensing data,we have monitored recent changes in cultivated land use and vegetation,in sandy areas and salinized desertification in the Green Corridor zone of the main channel of the Tarim River Basin.The results of our investigation show that the ecological environment in the Green Corridor of the main channel of the Tarim River Basin has conspicuously improved from 2002 to 2004.These improvements show up largely in such aspects as an increase in the rate of vegetation cover,a reduction in desertification land areas and a weakening in the intensity of sandy and the salinized land.On the other hand,the cultivated area in the Tarim River Basin significantly increased from 2002 to 2004.The rate of growth in cultivated areas during this period was significantly higher than that from 1999 to 2002.The increase in the use of irrigation resulting from the substantial increase in cultivated areas has a long-term potential restraining effect on the restoration of ecological functions of the Tarim River.

Changes of landuse form and their ecological effect on desert-steppe area in Ningxia

The central part of Ningxia is a desert-steppe area with a sparse population and fragile ecosystem where over-grazing has caused serious degeneration of steppe ecosystem; however, the southern part is a populous loessic hilly area subject to serious soil erosion. The central desert steppe has become an oasis with immigrants from southern loessic hilly area thanks to the implementation of new irrigated projects by pumping water from the Yellow River. Using government investment and loan of World Bank, the new irrigated area has been developed which covers an area of 32,527 ha with 145 thousand immigrants moving there from the southern loessic hilly area in 1984-1994. A new ecosystem of oasis economy has been established, socio-economic, and environmental benefits achieved, and changes in land use were prominent. In the central desert steppe of Ningxia, except the original pasture and dryland farming, irrigational farming, horticulture and livestock breeding have been developed. As a result, artificial ecosystems of various types have been formed in the irrigated areas mentioned above. This paper will particularly discusses the changes of landuse patterns in resultant ecological effects, and the environemntal problems for sustainable development in the irrigated area. For the changes of landuse patterns, four aspects are relevant: the dryland was changed into irrigated land, the grassland became irrigated farmland, the agricultural landuse pattern changed and the cropping patterns also altered. The ecological benefits of the irrigated area are as follows: 1) the desert-steppe has been partially replaced by man-made oasis; 2) drinking water for human and livestock was guaranteed; 3) the shifting sand dunes in some areas were brought under control; 4) soil erosion was mitigated; 5) soil mellow process was accelerated and soil fertility increased; and 6) the eco-economic system was diversified. Finally, the authors identifies solutions to the environmental problems, including water pollution. Soil secondary salinization, soil strucrure, improvement shelterbelt construction, all related to sustainable development in irrgational area.

Stability and Ecological Effects of Main Plant Communities in Minqin Desert Area

[ Objective ] To elucidate the change trend in stability and ecological effects of plant communities in desert along with global wanning. [ Method ] The data of site-specific observation on five main plant communities at ten plots in Minqin desert area were used to analyze the stability and ecological effects of desert plant communities by using two indicators vegetation coverage and projective cover degree. [ Results ] The vegetation coverage of Artemisia arenaria and Ephedra przewalskii, and the projective cover degree of A. arenaria and man-made Haloxylon ammodendron forest decreased remarkably; and the vegetation coverage of Ni- traria tangutorum was also decreased to some extent. [ Conduslon] （1） The plant communities with poor vegetation coverage gives a relatively strong stability, while that with high vegetation coverage has a relatively poor stability; （2） the yearly precipitation is the determinant of vegetation coverage and projective cover deglee; （3） the ecological function is found to be most remarkable in per unit area N. tangutorum, followed by E. przewalskii and N. tangutorum ＋H. ammodendron, and least in per unit area A. Arenaria. The vegetation is sparse in desert and plant branches does not distribute regularly, thus the crown-based vegetation coverage can not reflect the actual surface coverage.

Ecological Effects Measures and Regulation of Tourism Island

With the sustainable development of tourism in China, the phenomenon of ecological islanding in tourist attractions gradually becomes prominent, affecting the sustainable development of landscape and ecological environment in scenic spots. Tourist attractions are influenced by spatial location, resource characteristics and ecology, environmental protection and other factors. The appeals of government, tourism enterprises, developers and community villagers in the aspect of landscape and ecology are different in the development process of tourism, leading to different degrees, frequencies and scopes of tourism ecological islanding with prominent conflicts. This is a typical problem in the development stage of tourist attractions in China. Taking six scenic spots in Puzhehei as examples, the values of tourism ecological islanding were measured scientifically, and a anti-planning regulatory mechanism against tourism ecological islanding was established in this paper to achieve the sustainable development of the tourist attractions and ecological environment.

Ecological effects of Tongren City land transferring

The ecological effects of land transfer are mainly around the ecological effects of land itself. One is environmental and ecological effects of land, such as flood controlling, preventing soil erosion, preventing the collapse debris, water conservation and maintenance of biodiversity and conservation of wildlife. Second, it is crop residue use of land, including： treatment of organic waste, decomposing and eliminating contaminants, regulating microclimate and air purification, maintaining and revitalizing rural communities. Third, the geographical landscape effects of land, such as providing idyllic pastures and other entertainment services. In a conclusion, there is little exploration to the ecological effects of rural land. This paper attempts to analyze the environmental problems related to the land transferring in Tongren City.

The impact of urban morphology on multiple ecological effects:Coupling relationships and collaborative optimization strategies

Urban morphology significantly affects the ecological effects of urban heat islands,ventilation,and atmospheric pollution.Here,we reveal the mechanisms linking the ecological effects of urban morphology to develop a planning approach for the collaborative optimization of multiple ecological effects.Considering Shenyang,a cold city in northern China,as the study area,a multiple regression model of morphological parameters and ecological effects was established,and the impact of morphological parameters on ecological effects was explored.The results show that the aspect ratio of the streets,building density,and vegetation coverage are sensitive to multiple ecological effects.The inflection point of the ecological effect function curve occurs when the aspect ratio of the building and building density are 0.2 and 0.3,respectively.In addition,for optimal design applications in typical areas of the city,to obtain a Pareto-optimal urban morphology,Grasshopper is used to establish a parametric platform,wherein a genetic algorithm solves the multiple regression equation set.Ultimately,five ecological effect indicators are optimized and show 8.4%,5.0%,31.6%,33.1%,and 12.5%improvement.The study effectively constructs a collaborative optimization planning and design method for multiple ecological effects.

Compound contamination and secondary ecological effects of Cd and As in soil－alfalfa ecosystems

d and As both have harmful effects on the growth,development and seed germination of alfalfa, especially in such a condition as the coexistence of Cd and As in soil environment The research using the pot-culture imitative method first found that if soil was simultaneously polluted by Cd and As,function of alfalfa absorbing Cd from soil may be promoted because of the existence of As,in conversely,Cd may inhibit alfalfa plant from absorbing As It was also found that secon- dary ecological effects were most likely to be brought out due to the coexistence of Cd and As. For example,alfalfa is passive to excessively absorb Cu and Pb .The harmful effects undoubtedly intensi- fy the contamination of alfalfa, The results showed that the mechanism of the interaction among Cd,As,Pb and Cu in soil-alfalfa ecosystems is very complicated.

Research Progress on Farmers’Livelihood Transformation and Its Ecological Effects——A Review

Farmers’livelihoods and their impacts on the ecosystem are important indicators of human-land relationships.Appropriate livelihood strategies for farmers can meet the needs of human well-being and promote the sustainable use of natural resources,thereby maintaining the health and stability of natural ecosystems.Scholars have carried out a great deal of research on the changes in farmers’livelihoods,as well as the driving mechanisms and ecological effects,but there are still many controversial issues about the ecological effects of farmers’livelihood transformation.On the basis of collecting and sorting out the relevant literature,this paper analyzes the previous research results on the transformation mechanism and ecological effects of farmers’livelihoods,and further explores the coupling relationship.Through the analysis and summary,we find that the choice of farmers’livelihoods is affected by natural factors,subjective willingness and social policies.The transformation of farmers’livelihood changes the ways of production,consumption and resource utilization,which in turn profoundly affects the evolutionary process of the natural ecosystems.This paper establishes a research framework for the livelihood transformation mechanism of farmers and its ecological effect,and finally summarizes two directions that need to be studied further in the future:(1)Exploring the interactions between the driving factors of farmers’livelihood transformation;and(2)Exploring a win-win sustainable mechanism for farmers’livelihood needs and natural resource utilization.

Clearcuts and related secondary dieback undermine the ecological effectiveness of FSC certification in a boreal forest

Background:Over the last 25 years,the prominent forest certification system established by the Forest Stewardship Council(FSC)has used by many companies worldwide for claiming responsible forest management.The objectives of the Russian National FSC standard to decrease the size of clearcuts and the retention of forest elements such as residual seed trees need on-site validation to proof the effectiveness of FSC.To assess the ecological impacts of harvesting practices and benefits of FSC certification,we geospatially compared logging activities with and without FSC certification.Within a sample area covering approximately 3,000 km^(2) in the east of the Russian Arkhangelsk Region,we used available data on tree cover loss and satellite images to assess secondary impacts of clearcuttings on adjacent remnant forests and to quantify the logging intensity.Additionally,the size and structure as well as the density of skidding trails of ten specific clearcuttings located within the sample area were surveyed using satellite images and in the field observation to delineate the boundaries of clearcuts and forested remnants within the clearcuts.Results:We found a significant increase of small-scale tree cover loss in the proximity of the clearcuts.Patchy dieback is possibly linked to the scale and intensity of logging in the surroundings.On the investigated clearcuts,FSC failed to reduce the size,to increase the retention of forest remnants including seed trees on logged areas,and to maintain larger tracts of undisturbed ground and soil compared to clearcuts that were logged before they received FSC-certification.Conclusions:Trees and forest remnants remaining inside an increasingly stressed forest ecosystem matrix may not resist further harvesting-related and climate change-induced stresses and disturbances.Large-scale clearcuttings seem to have negative impacts even in adjacent forests and undermine the ecological effectiveness of FSC certification in the study area.The Russian FSC standard is not clearly setting effective guidelines that induce a change in clearcutting practices in order to reduce ecological risks.

Ecological and socioeconomic effects of China's policy for grassland eco-compensation

To reverse the continuous deterioration of grassland ecology and to improve the well-being of herders, China has been formulating many national policies on payments for grassland ecological conservation. One of them, the Grassland Eco-compensation Policy(GEP), is the biggest program for grassland protection in China since 1949. The GEP conserves natural grassland by paying herders cash subsidies. It also has worldwide significance because it can increase vegetative cover, improve the ecological balance, increase carbon sequestration and lessen the amount of dust reaching other countries through inhibiting soil erosion. Overall, we find that its ecological and socioeconomic effects are beneficial and further benefits may be observed in the future because while the socioeconomic effects usually appear quickly, ecological effects may take longer to manifest. 2015 is the last year for the first round of the GEP policy implementation and the extended policy for the GEP will be approved and continued by the central government. To make the policy more successful, we suggest coordinated planning, a comprehensive overview, higher compensation and collaborative study. Efficient implementation of the GEP could also provide valuable experience for other eco-compensation programs in China and numerous other regions of the world.

Variations of nutrient elements and its effect on ecological environment off the Changjiang estuarine waters

On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The transform mechanism of present species of nutrients and the of differrnt water masses, frontal area and thermohaline transition layer on convergence or divergence and the biogeochemical cycle of nutrient elements off the Changjiang Estuary are studied. Meanwhile, the environmental capaci- ty of nutrients is primarily estimated: they are 1.803 x 104t DIN and 6.18 x 102t PO43- -P in autumn, and 4.20x 102t PO43- -P in spring.

The Research on Land-Use Change and Ecological Environment Effect of Urban Landscape in China

The rapid expansion of urban construction land has become the major characteristic of urban land-use change in China today. Meanwhile, the rapid urbanization process has led to the great changes of urban landscape in China, and it also has had certain impacts on environmental factors such as climate, soil, hydrology, biodiversity, etc., then it has made the overall ecological environment deteriorated. This study is based on the summary and analysis of research on land-use change and ecological environment effect of urban landscape in recent 20 years in China, and it aims at providing scientific bases and theoretical supports for the planning and construction of urban landscape, the sustainable land-use of city and the protection of ecological environment in China.

ECOLOGICAL LANDSCAPE EFFECTS OF WINDBREAK SYSTEMS IN DESERT ZONE OF WESTERN CHINA

This paper, by applying the theories of landscape ecology, illustrates the role and mechanism of windbreak system in the establishment and maintenance of oasis ecosystem on the basis of systematic analysis of characteristics and ecological crises of China's desert, and especially of desert zone in western China. Furthermore, direct economic benefits are summarized.