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181.
Land use change is influenced by a complexity of drivers that transcend spatial, institutional and temporal scales. The analytical framework of telecoupling has recently been proposed in land system science to address this complexity, particularly the increasing importance of distal connections, flows and feedbacks characterising change in land systems. This framework holds important potential for advancing the analysis of land system change. In this article, we review the state of the art of the telecoupling framework in the land system science literature. The article traces the development of the framework from teleconnection to telecoupling and presents two approaches to telecoupling analysis currently proposed in the literature. Subsequently, we discuss a number of analytical challenges related to categorisation of systems, system boundaries, hierarchy and scale. Finally, we propose approaches to address these challenges by looking beyond land system science to theoretical perspectives from economic geography, social metabolism studies, political ecology and cultural anthropology.  相似文献   
182.
At the Sulm River, an Austrian lowland river, an ecologically orientated flood protection project was carried out from 1998-2000. Habitat modeling over a subsequent 3-year monitoring program (2001-2003) helped assess the effects of river bed embankment and of initiating a new meander by constructing a side channel and allowing self-developing side erosion. Hydrodynamic and physical habitat models were combined with fish-ecological methods. The results show a strong influence of riverbed dynamics on the habitat quality and quantity for the juvenile age classes (0+, 1+, 2+) of nase (Chondrostoma nasus), a key fish species of the Sulm River. The morphological conditions modified by floods changed significantly and decreased the amount of weighted usable areas. The primary factor was river bed aggradation, especially along the inner bend of the meander. This was a consequence of the reduced sediment transport capacity due to channel widening in the modeling area. The higher flow velocities and shallower depths, combined with the steeper bank angle, reduced the Weighted Useable Areas (WUAs) of habitats for juvenile nase. The modeling results were evaluated by combining results of mesohabitat-fishing surveys and habitat quality assessments. Both, the modeling and the fishing results demonstrated a reduced suitability of the habitats after the morphological modifications, but the situation was still improved compared to the pre-restoration conditions at the Sulm River.  相似文献   
183.
Motivated by the detection of 131I in river sediment in routine long-term surveillance samples, a systematic short-term study of the wastewater treatment chain was planned and conducted. Inflow, effluent and primary sludge were collected on a daily basis during two weeks at a regional wastewater treatment plant. Samples were investigated by gamma spectroscopy. Four medically used isotopes could be identified (131I and 99mTc regularly, 153Sm and 123I sporadically). The concentration levels coincide well with literature data for 131I, and with our own long-term data for 131I and 99mTc for the same plant. Cosmogenic 7Be activity in primary sludge correlated well with rainfall intensity. Surface sediment was sampled at low tide at both shores of the river, up- and downstream of the plant. 131I was identified in all samples, with a sharp maximum (about 100 Bq kg−1 d.m.) at the discharge point of the plant and lower levels elsewhere, decreasing monotonically in downstream direction. 7Be and 137Cs showed the same behaviour, but no peak at the discharge point. Predictions from simple equilibrium models for the transport and sedimentation of 131I show good agreement with the experimental data and suggest that the wastewater treatment plant is the main source for this isotope.  相似文献   
184.
Asian nations are currently facing a number of challenges, including environmental degradation and growing societal inequalities, in the course of their rapid economic growth and industrialization. Under such conditions, it is of critical importance to develop appropriate assessment tools with which to comprehensively measure the sustainability status of a region in order to guide its transformation into a sustainable society. This paper proposes a method of sustainability assessment consisting of the three components of environment, resource, and socio-economic with aggregated time-series scores. This method can demonstrate the relative sustainability scores of targeted regions for different time periods, thereby, enabling the comparison of relative sustainability status for different regions over these periods. We carried out a case study of Chinese provinces for the years 2000 and 2005 using the proposed method and confirmed its applicability as the indicative type of sustainability assessment at the regional level, while actually investigating the sustainability status and its chronological changes. The results indicated that aggregate sustainability index scores improved between 2000 and 2005 in most provinces, mainly due to significant improvement in the scores for the socio-economic component, whereas the scores for the environment component deteriorated in some provinces over the study period. Our method proves to be effective in analyzing the relative sustainability status among targeted regions for different time periods in the form of aggregate scores, paving the way for practical applications, such as policy analysis, in the pursuit of a sustainable society.  相似文献   
185.
The information on temperature-mediated changes in biodiversity in local assemblages is scarce and mainly addresses the change in species richness. However, warming may have more consistent effects on species turnover than on the number of species. Moreover, very few studies extended the analysis of changes in biodiversity and species composition to questions of associated ecosystem functions such as primary production. Here, we synthesize 4 case studies employing microalgal microcosms within the Aquashift priority program to ask (1) do warming-related shifts in species richness correspond to changes in the rate of biomass production, (2) do similar relationships prevail for evenness, and (3) do warming-related shifts in species turnover stabilize or destabilize biomass production? Two of the four cases are previously unpublished, and for a third case, the link between diversity and functional consequences of temperature was not analyzed before. We found accelerated loss of species with warming in all cases. Biomass production was lower with lower species richness in most cases but increased with lower evenness. Most importantly, the relation between functional and compositional stability was different between cases: More rapid extinction resulted in more variable biomass in 2 cases conducted with a limited species pool, indicating that compositional destabilization relates to functional variability. By contrast, the only experiment with a large species pool (30 species) allowed previously rare species to become dominant in the community and showed more stable biomass at high turnover, indicating that compensatory dynamics (turnover) can promote functional stability. These 4 independent experiments highlight the need to consider both compositional and functional consequences of altered temperature regimes.  相似文献   
186.
187.
One of the most important and yet difficult challenges that modern societies face is how to mobilize science and technology (S&T) to minimize the impact of human activities on the Earth’s life support systems. As the establishment of inter-disciplinary education programs is necessary to design a unified vision towards understanding the complexity of human nature, the Research Institute for Sustainability Science (RISS) launched a new program on sustainability science in April 2008. The program expects to address the issue of how to use knowledge more effectively to understand the dynamic interactions between nature and human society. This paper first offers an overview of international and Japanese initiatives on sustainability education in which we highlight the uniqueness of the attempt by the Integrated Research System for Sustainability Science (IR3S). The paper then introduces the RISS program for sustainability science, addressing the principles and curriculum design of the program. The paper discusses the main problems and constraints faced when developing the program, such as institutional barriers in building a curriculum and obtaining cooperation from faculty. To challenge these barriers and limitations, the RISS uses the program as a platform to disseminate the idea of sustainability science across the university. This attempt helps us to obtain the continuing cooperation necessary to improve and maintain the program.
Michinori UwasuEmail:
  相似文献   
188.
The effects of changing climatic and socioeconomic conditions on the water quality of the Elbe River were investigated using the deterministic model QSim. Since the impact of global change on river water quality marks the endpoint of various processes in the catchment and in the atmosphere, this study was performed within a network of interacting models that determined input parameters for water quality simulations. The development of phytoplankton and nutrient concentrations under conditions of global change was modeled along a 700 km stretch of the river. The simulations revealed a strong, scale-dependent effect of climate change on phytoplankton biomass, leading to a longitudinal shift of the dominating processes (primary productivity vs. respiration) along the river continuum. Under reduced flow, combined with increasing temperature and global radiation, phytoplankton biomass increased and phytoplankton maxima shifted in upstream direction, followed by higher system respiration rates in the adjacent downstream sections. In contrast, higher flow shifted the phytoplankton maximum toward the downstream sections. Even a drastic reduction of phosphorus inputs from anthropogenic sources had only limited influence on algal biomass, due to the ability of algal cells to store phosphorus. A strong reduction in P-inputs especially in the headwaters would be necessary to counterbalance the possible climate-induced effects on algal biomass.  相似文献   
189.
When food producing animals are contaminated with PCDD/F congeners, information on the contaminant’s concentration in the bodies of the animals at time of slaughter is needed for risk management purposes. We have developed a mathematical model for the kinetics of PCDD/Fs in growing pigs in case of contaminated feed fed for a limited duration of time. This model allows the prediction of concentrations in body fat. It considers absorption fractions of PCDD/Fs, clearance by metabolism, dilution by growth and excretion through fecal fat. The model parameters were calibrated by fitting the model to experimental data. On the basis of this toxicokinetic model a probabilistic model has been constructed. The probabilistic model handles the parameters with appropriate probability distributions and Monte-Carlo simulation technique, providing for realistic situations with many animals and a range of contaminations and feeding intervals. We applied the new model to describe the German dioxin incident of winter 2010/2011 and discuss its viability as decision tool. The approach demonstrated here is a showcase how a risk assessment in the case of contaminated feeding can be performed.  相似文献   
190.
In this study, a two-dimensional liquid chromatography tandem mass spectrometry method was developed and validated for the determination of pesticide residues and contaminants in whole wheat grains and oats. The samples were extracted with a mixture of acetonitrile and water and were injected into the two-dimensional LC-MS/MS system without any further clean-up or sample preparation. Samples were analyzed with four different matrix matched calibrations. Matrix effects were evaluated by comparing analyte signals in the respective matrix matched standard with the neat solvent standards. The final method was validated according to the current Eurachem validation guide and SANTE document. The number of successfully validated analytes throughout all three validation levels in oats and wheat, respectively, were as follows: 330 and 316 out of 370 pesticides, 6 and 13 out of 18 pyrrolizidine alkaloids and 7 out of 9 regulated mycotoxins. Moreover, both plant growth regulators mepiquat and chlormequat as well as the tropane alkaloids atropine and scopolamine met the validation criteria. The majority of pesticides showed limits of detection below 1?µg kg?1, pyrrolizidine alkaloids below 0.7?µg kg?1, tropane alkaloids below 0.2?µg kg?1, growth regulators below 0.7?µg kg?1 and mycotoxins below 8?µg kg?1 in both matrices.  相似文献   
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