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71.
Background and aim Grassy field margins have a high relevance in agricultural landscapes regarding the preservation of typical arthropod communities, their biodiversity and the ecological system functions linked with it. The structure of terrestrial communities is affected by anthropogenic impairment, which can lead to the replacement of sensitive by more tolerant species. The negative influence of pesticides on fauna and flora as well as the associated functional aspects (ecological system functions) and the reduction of biodiversity are undisputed since longer for agrarian systems and can also be assumed for grassy field margins due to spray-drift. The case study presented here examined the effect of influences related to utilization on the plant and arthropod communities of grassy field margins. Reference sites, on which due to missing farming in the direct surrounding countryside no utilization influences on the communities were present, were compared to non-target sites, on which these influences could not be excluded. Sites in three German macrochores were examined: in the Jülicher Börde, at the northeastern edge of the Leipziger low lands and in the area Mainfranken near Würzburg, all of them intensely used agricultural landscapes. Beside the vegetation, the epigeic arthropod communities of carabid beetles, spiders, springtails, hymenopterans, hover flies and ladybirds as well as abiotic parameters were included in the analysis. The aim of the study was the development of a statistical exclusion procedure which is capable to quantify the amount of variation in field community data which can be attributed to isolated factors. Special attention was paid to non-observable utilization impacts like undocumented pesticide application. The extraction of patterns of residual variance allowed for the uncovering of masked effects on a scale below the obvious abundance pattern. Materials and methods The variability in the species composition was visualized with the help of non-metric multi-dimensional scaling (NMDS). Indicator species analysis revealed those species which could be recognized as statistically significant indicators for local conditions. The relationship between the species composition and the environmental factors was statistically modeled by canonical correspondence analysis. By variance partitioning it was possible to extract the variance portion which could be bound to a set of covariables. For the remaining residual variance it could not be excluded that this resulted from a pesticide influence. Results The analyses based on the ecological distance (Bray-Curtis) showed that the communities in references sites and non-target sites could be clearly distinguished in all three landscapes. Based on the portions of variance which could be explained statistically by a utilization related influence, two different directions of reaction to the utilization related variables could be stated. On the one hand there were sensitive species, showing reduced abundances in the non-target sites, on the other hand there were species increasing in abundance in the non-target sites, recruiting from the group of strong competitors. Discussion By the use of residual variances a clear influence of utilization related parameters on the community of soil arthropods and vegetation could be shown. The observed abundances shifts between reference sites and non-target sites in the raw data were attributed to a multi-dimensional factor complex which could be split up by the use of partial ordination methods, quantifying the relationships to the utilization related parameters. It was demonstrated that special utilization correlated patterns could be found in the raw data after eliminating the influence of the covariables. Conclusions Utilization related influences in the non-target sites evened out the characteristic communities for the three landscapes towards a comprehensive, ubiquitous species composition. The hypothesis of decreasing abundance of sensitive species and the augmentation of tolerant species due to a potential pesticide influence could be underpinned and quantified. Sensitive species which showed a significant reduction in abundance between reference and non-target sites showed a much higher sensitivity to the influences and thus were assigned a higher indicator potential than tolerant species. From the group of the sensitive species Pardosa palustris and Poecilus cupreus could be isolated as two promising macrochore-specific indicator species for the masked effects. Recommendations and perspectives A macrochore-specific assessment of utilization effects was requested for future studies due to the different sensitivities of the species in the three landscapes. The elaboration and specifying of reference conditions for terrestrial agrarian systems is an important task for the future. The presented approach deduces a macrochore-specific, complex effect pattern of anthropogenic impairment on terrestrial species communities. It can be used to extract masked effects and by this facilitates a more sustainable use of e.g. plant protection products. Furthermore it provides an opportunity to validate evaluation systems for the effects of utilization impacts on terrestrial vegetation and arthropods. Additionally the species sensitivities with respect to the macrochores allow a regionalized assessment of ecotoxicological effects and the integration into spatially explicit effect assessment models.  相似文献   
72.
State and federal governments in Australia have implemented a range of assistance programs for manufacturing industries to become more resource efficient and reduce waste. While many of these programs focus on Cleaner Production at single sites, an increasing number of assistance programs are offered across supply chains. Sustainability Victoria, a Victorian government authority, supports projects that focus on resource efficiencies across supply chains in key industry sectors.In this study, tools were adapted and utilised to identify efficiency potentials and losses across supply chains in the timber furniture manufacturing and the food industry sector. In this respect, waste generation and value loss due to inefficient use of critical materials within the processes were estimated from purchase and waste handling data. Primary companies were chosen to undertake efficiency trials that could demonstrate value gain across the supply chain.This study describes the realisation of greater efficiencies in material usage when engaging proactively with supply chain partners immediately adjacent to the primary company. Demonstration trials confirmed that through a more integrated approach among supply chain partners the potential in using materials more efficiently and design processes can lead to enhanced productivity without compromising environmental burden. Hence, the study describes targeted resource efficiency, recycling and process optimisation opportunities as identified in the supply chain trials on timber furniture manufacturing and food industries.  相似文献   
73.

Goal, Scope and Background

Nitrodiphenylamines can be found at abandoned military sites where the explosive 2,2′,4,4′,6,6′-hexanitrodiphenylamine (hexyl) or diphenylamine as a stabilizer of smokeless powder was handled. Aim of the present study is the development of HPLC methods for the analysis of contaminants which can be expected in particular under aerobic conditions at premises which are contaminated by nitrodiphenyl-amines and related compounds.

Methods

A list of 13 compounds which can be expected at these explosives factories was deduced from literature studies. HPLC methods were developed for the analytes. Water samples from the unsaturated zone of a former hexyl-producing factory were collected by suction cups and the material was analysed according to these procedures to demonstrate the practicability of the new methods and to verify the existence of the postulated compounds in the environment of the former nitration plant.

Results and Conclusion

The new HPLC methods are suitable for the exploration of sites contaminated by nitrodiphenylamines. Beside some hexyl its intermediates 1-chloro-2,4-dinitrobenzene, 2,4-dinitrodiphenylamine und 2,2′,4,4′-tetranitrodiphenylamine were identified in the leachate water.

Recommendation and Perspective

It is advisable to include at least these 4 compounds in the examination of former hexyl-producing plants. Several unknown peaks were observed in the HPLC-chromatogram. It is recommendable to perform further investigations of the unidentified compounds to compile a final list of analytes for military sites polluted by nitrodiphenylamines.  相似文献   
74.
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76.
The formation of the North Water in Smith Sound about 4500 years ago, as evidenced by the establishment of bird colonies and human presence, also initiated a long-term anthropogenic agent as part of this High Arctic ecosystem. Different epochs have influenced the human occupation in the area: immigration pulses from Canada and Alaska, trade with meteorite iron throughout the Arctic, introduction of new technologies by whalers and explorers, exploitation of resources by foreigners, political sequestration, export of fox and seal skins and later narwhal products, and recently fishing. Physical drivers in terms of weather and climate affecting the northern hemisphere also impact accessibility and productivity of the ecosystem, with cascading effects on social drivers, again acting back on the natural ecologies. Despite its apparent isolation, the ecosystem had and still has wide ranging spatial ramifications that extend beyond the High Arctic, and include human activity. The challenge is to determine what is internal and what is external to an ecosystem.  相似文献   
77.
78.
A recent article in Environmental Management by All argued that flood flows in North America’s Colorado River do not reach the Gulf of California because they are captured and evaporated in Laguna Salada, a below sea-level lakebed near the mouth of the river. We refute this hypothesis by showing that (1) due to its limited area, the Laguna Salada could have evaporated less than 10% of the flood flows that have occurred since 1989; (2) low flow volumes preferentially flow to the Gulf rather than Laguna Salada; (3) All’s method for detecting water surface area in the Laguna Salada appears to be flawed because Landsat Thematic Mapper images of the lakebed show it to be dry when All’s analyses said it was flooded; (4) direct measurements of salinity at the mouth of the river and in the Upper Gulf of California during flood flows in 1993 and 1998 confirm that flood waters reach the sea; and (5) stable oxygen isotope signatures in clam shells and fish otoliths recorded the dilution of seawater with fresh water during the 1993 and 1998 flows. Furthermore, All’s conclusion that freshwater flows do not benefit the ecology of the marine zone is incorrect because the peer-reviewed literature shows that postlarval larval shrimp populations increase during floods, and the subsequent year’s shrimp harvest increases. Furthermore, freshwater flows increase the nursery area for Gulf corvina (Cynoscion othonopterus), an important commercial fish that requires estuarine habitats with salinities in the range of 26–38‰ during its natal stages. Although flood flows are now much diminished compared to the pre-dam era, they are still important to the remnant wetland and riparian habitats of the Colorado River delta and to organisms in the intertidal and marine zone. Only a small fraction of the flood flows are evaporated in Laguna Salada.  相似文献   
79.
The expert panel for biological indication and effect research of the state institutes and agencies, pursues the harmonisation and optimisation of methods used for biological indication since 1980. This demonstrated increased significance after the fall of the Berlin Wall and the admission of the new German states, formerly East Germany. The publication of recommendations and the co-operation with other panels of experts (for example the VDI (association of German engineers) build the basis for the expert panel’s effect on the public. As first federal biological indication system, the expert panel, together with the federal institute for the environment, introduced moss-monitoring in the Federal Republic of Germany. For the future, the main point of effort will still lie in the exchange of information between state agencies and the harmonisation of methods. Above this, the expert panel should control the co-ordination of biological indication for a federal environment surveillance, develop evaluation strategies and methods, point out research deficiencies and develop new methods when necessary. Thus, for example, the expert panel has to point out possible connections and co-operations towards the monitoring of genetically manipulated organisms and changes in climate. Existing biological indication methods, including moss-monitoring, are to be screened for actuality and, when necessary, are to undergo further developments. The expert panel will also work on the development of effect-related environmental indicators as tools for an indication of ecological sustainability.  相似文献   
80.
Arthrogryposis multiplex congenita (AMC) refers to an aetiologically heterogenous condition, which consists of joint contractures affecting two or more joints starting prenatally. The incidence is approximately one in 3000 live births; however, the prenatal incidence is higher, indicating a high intrauterine mortality. Over 320 genes have been implicated showing the genetic heterogeneity of the condition. AMC can be of extrinsic aetiology resulting from intrauterine crowding secondary to congenital structural uterine abnormalities (eg, bicornuate or septate uterus), uterine tumors (eg, fibroid), or multifetal pregnancy or intrinsic/primary/fetal aetiology, due to functional abnormalities in the brain, spinal cord, peripheral nerves, neuromuscular junction, muscles, bones, restrictive dermopathies, tendons and joints. Unlike many of the intrinsic/primary/fetal causes which are difficult to treat, secondary AMC can be treated by physiotherapy with good response. Primary cases may present prenatally with fetal akinesia associated with joint contractures and occasionally brain abnormalities, decreased muscle bulk, polyhydramnios, and nonvertex presentation while the secondary cases usually present with isolated contractures. Complete prenatal and postnatal investigations are needed to identify an underlying aetiology and provide information regarding its prognosis and inheritance, which is critical for the obstetrical care providers and families to optimize the pregnancy management and address future reproductive plans.  相似文献   
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