Planktonic protist communities in semi-enclosed mariculture waters: temporal dynamics of functional groups and their responses to environmental conditions

The functional groups of planktonic protist communities and their responses to the changes of environmental conditions were investigated in a semi-enclosed shrimp-farming pond in Qingdao,Shandong Province,China,during a six-month study period （a complete shrimp-culture cycle） from May to October 2002.The results reveal that： （1） the protist communities represented five trophic and functional groups of the species identified,about 60% were photoautotrophs,20% algivores,12% bacterivores,5% raptors and about 3% non-selectives;（2） the photoautotrophs,algivores and bacterivores were the primary contributors to the changes in the protist communities in short temporal scales,the succession of dominance typically being bacterivores→photoautotrophs→algivores,with the raptors dominating the protist communities in a single sample （early June）;（3） the photoautotrophs and non-selectives were the primary contributors to the peak of protist abundance in early October whereas the photoautotrophs,bacterivores,raptors and non-selectives mainly gave rise to two bimodal peaks of biomass in July and October respectively;（4） five functional groups of protist communities represented significant correlations with water nutrients （i.e.,NH 3-N,NO 3-N,and PO 4 ）,either alone or in combination with temperature,of which algivores and raptors were strongly correlated with phosphate and the concentration of Chl a,while bacterivores were strongly related to nitrogen and the concentration of bacteria.These findings confirm that planktonic protists are potentially useful bioindicators of water quality in the semi-enclosed mariculture system.

Functional diversity of Cercidiphyllum japonicum, communities in the Shennongjia Reserve, central China

Functional diversity is significant to ecological processes of plant communities. We analyzed the variation of functional diversity of endangered species, Cercidiphyllum japonicum, communities along an elevational gradient in the Shennongjia Reserve, central China. Sixty plots of 10 9 20 m from 1,350 to 2,050 m were set up and species composition, traits and environmental variables were measured and recorded. These data were analyzed using five functional diversity indices, functional attribute diversity, modified functional attribute diversity, plot based functional diversity, community based functional diversity and Rao＇s functional diversity indices（Rao＇s index）,Functional diversities of C. japonicum communities were rich and varied greatly. Functional diversity declined nonlinearly with increasing elevation. Functional diversity was significantly correlated with species richness and heterogeneity. Elevation was a key environmental variable influencing functional diversity and species diversity. The five functional diversity indices were all effective for measuring functional diversity of communities. Functional diversity can be used as an indicator of conservation efficiency of endangered species such as C. japonicum.

Environmental rehabilitation of damaged land

Background:Much land is subject to damage by construction,development and exploitation with consequent loss of environmental function and services.How might the loss be recovered?Results:This article develops principles of environmental rehabilitation.Key issues include the following.Rehabilitation means restoring the previous condition.Whether or not to restore is not a technical but a value judgement.It is subject to adopting the sustainability ethic.If the ethic is followed under rule of law then rehabilitation must be done always to’the high standard’which means handing down unimpaired environmental function and no extra land management.The elements of the former condition that it is intended to restore must be specified.Restoring these in any given case is the purpose of that rehabilitation project.The specified restoration elements must be easily measurable with a few simple powerful metrics.Some land damage is not fixable so restraint must be exercised in what construction,development and exploitation are permitted.If sustainability is adopted then cost benefit analysis is not a valid form of project appraisal because trading off present benefits against future losses relies on subjectively decided discount rates,and because natural capital is hard to price,indispensable,irreplaceable and non-substitutable.Elements often to be restored include agricultural land capability,landscape form and environmental function.Land capability is a widely used convention and,with landscape form,encapsulate many key land factors,and are easily measurable.Restoring soil and thereby environmental function provides the necessary base for an ecological pyramid.Conclusions:The need for rehabilitation is not to be justified by cost-benefit or scientific and technological proof,but rests on a value judgement to sustain natural capital for present and future generations.Decision on what activities and projects to permit should be based on what is physically and financially fixable on current knowledge.Business and government must be proactive,develop rehabilitation standards,work out how to meet the standards,design simple powerful metrics to measure performance against the standards,embark on continuous improvement,and report.

The Space Dissimilation of Stakeholders' Environment Cognitive and Behavior Preference Response in the Area from Returning Fazing Land to Grasslands

The cognition and attitudes of resources environment affect environmental behavior of behavior subject,the changes of attitude and behavior become one of the key factors of influencing harmonious and healthy development of ecological environment. With PRA survey method for obtaining questionnaire data and based on behavior geography and social psychology theory,farming-pastoral,dry grassland,desert grassland, typical project village alpine grassland of returning fazing land to grasslands as an example,with main body cognitive perspective of the aid of resources,the article analyzed space dissimilation of stakeholders environmental cognitive and behavior preference response in the area of returning grazing land to grasslands from ecological environment from policy environment,ecological environment and family economic environment aspects. The results showed that： stakeholders judgment of Grassland degradation in different ecological function area had obvious regularity,the cognitive proportion of Grassland degradation gradually increase from farming-pastora to alpine savanes. The satisfaction from returning grazing land to grasslands showed a changing tendency of reversed U. stakeholders had more strongly negative cognition in the area of dry steppe and desertsteppe. From farming-pastoral to alpine savanes,the economic environment tend to worse situation. Negative environmental behaviors tend to increase,Positive behavior on the contrary.

Research on ballistic missile laser SIMU error propagation mechanism

It is necessary that the laser inertial system is used to further improve the fire accuracy and quick reaction capability in the ballistic missile strapdown inertial navigation system. According to the guidance controlling method and the output and error model of ballistic missile laser SIMU, the mathematical model of error propagation mechanism is set up and any transfer environmental function of error coefficient that affects the fire accuracy is deduced. Also, the missile longitudinal/lateral impact point is calculated using MATLAB. These establish the technical foundation for further researching the dispersion characteristics of impact point and reducing the laser guidance error.

Vegetation Restoration Technique System and Its Ecological Functions of the Degraded Ecosystem in the Arid-Hot Valleys——Taking the Example of Typical Mode in Small Watershed of Yuanmou

This paper concluded the vegetation restoration technique system in the arid-hot valleys and studied the anti-erosion function, environmental function and biological diversity effects of vegetation restoration on the ecosystem in the arid-hot valleys. The results showed that the soil erodibility decreased significantly after the vegetation restoration. The climate environment of the small watershed had a great improvement after the vegetation restoration, of which the temperature decreased, the humidity increased, the harsh environment of dry and hot in this region changed. The studies of the ecosystem biodiversity were mainly on the analysis of the relations between biodiversity and ecological function of the artificial ecological forest pattern and the natural enclosed treatment mode on the severely of degraded land. It could conclude that the natural enclosed treatment mode is helpful to the biodiversity of the ecosystem and the improvement and stability of the ecosystem, and Leucaena artificial forest restoration pattern reduced the species diversity but optimized the ecological function. Therefore, as to the severely and extremely severely degraded ecosystem in the arid-hot valleys, Leucaena pattern of gully control and natural enclosed treatment mode are the relatively optimal choices.

Vehicular Electronic Image Stabilization System Based on a Gasoline Model Car Platform

Noise,vibration and harshness(NVH)problems in vehicle engineering are always challenging in both traditional vehicles and intelligent vehicles.Although high accuracy manufacturing,modern structural roads and advanced suspension technology have already significantly reduced NVH problems and their impacts;off-road condition,obstacles and extreme operating condition could still trigger NVH problems unexpectedly.This paper proposes a vehicular electronic image stabilization(EIS)system to solve the vibration problem of the camera and ensure the environment perceptive function of vehicles.Firstly,feature point detection and matching based on an oriented FAST and rotated BRIEF(ORB)algorithm are implemented to match images in the process of EIS.Furthermore,a novel improved random sampling consensus algorithm(i-RANSAC)is proposed to eliminate mismatched feature points and increase the matching accuracy significantly.And an adaptive Kalman filter(AKF)is applied to improve the adaptability of the vehicular EIS.Finally,an experimental platform based on a gasoline model car was established to validate its performance.The experimental results show that the proposed EIS system can satisfy vehicular performance requirements even under off-road condition with obvious obstacles.

Graphitic carbon nitride with different dimensionalities for energy and environmental applications

As a metal-free semiconductor,graphitic carbon nitride(g-C3N4)has received extensive attention due to its high stability,nontoxicity,facile and low-cost synthesis,appropriate band gap in the visible spectral range and wide availability of resources.The dimensions of g-C3N4 can influence the regime of the confinement of electrons,and consequently,g-C3N4 with various dimensionalities shows different properties,making them available for many stimulating applications.Although there are some reviews focusing on the synthesis strategy and applications of g-C3N4,there is still a lack of comprehensive review that systemically summarises the synthesis and application of different dimensions of g-C3N4,which can provide an important theoretical and practical basis for the development of g-C3N4 with different dimensionalities and maximises their potential in diverse applications.By reviewing the latest progress of g-C3N4 studies,we aim to summarise the preparation of g-C3N4 with different dimensionalities using various structural engineering strategies,discuss the fundamental bottlenecks of currently existing methods and their solution strategies,and explore their applications in energy and environmental applications.Furthermore,it also puts forward the views on the future research direction of these unique materials.

Changes in major factors affecting the ecosystem health of the Weihe River in Shaanxi Province, China

Maintenance of the ecosystem health of a river is of great importance for local sustainable development. On the basis of both qualitative and quantitative analysis of the influence of natural variations and human activities on the ecosystem function of the Weihe River, the changes in major factors affecting its ecosystem health are deter- mined, which include： 1） Deficiency of environment flow： since the 1960s, the incoming stream flow shows an obvious decreasing tendency. Even in the low flow period, 80% of the water in the stream is impounded by dams for agriculture irrigation in the Baoji district. As a result, the water flow maintained in the stream for environmental use is very limited. 2） Deterioration of water quality： the concentrations of typical pollutants like Chemical Oxygen Demand （COD） and NH3-N are higher than their maximum values of the Chinese environmental quality standard. Very few fish species can survive in the River. 3） Deformation of water channels： the continuous channel sedimentation has resulted in the decrease in stream gradient, shrinkage of riverbed and the decline in the capability for flood discharge. 4） Loss of riparian vegetation： most riparian land has been occupied by urban construction activities, which have caused the loss of riparian vegetation and biodiversity and further weakened flood control and water purification functions.