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961.
962.
Since the introduction of the industrial ecology concept by Frosch and Gallopoulos in 1989, and the apparent success of the Kalundborg Industrial Symbiosis project, attention to planned eco-industrial park (EIP) development projects has grown all over the world. This article includes data from six of these EIP development projects. Three of the projects discussed are located in the Netherlands and three in the US. This article compares the differences in project approach and results on a national level. The approach suggested is derived from the available EIP development literature.Initial research indicates that the Dutch EIP projects are more successful than their US counterparts. This difference in success can be, mostly, attributed to the fact that the US projects are initiated by local and regional governments that see the project as a way to improve the local/regional economy with access to substantial government funds. Because of this heavy government involvement, US companies are, in general, not interested in the project. The more successful Dutch projects, on the other hand, are mostly initiated by the companies themselves with financial and advisory support from the local and regional government.  相似文献   
963.
The formicine ant Polyrhachis lama is a social parasite, exploiting its ponerine host ant species Diacamma sp. In most social parasitic associations, the parasitic species are closely related to their host species group, evolving directly from independent ancestors of the host species. However, in the Polyrhachis lamaDiacamma sp. association, the associated species belong to different ant subfamilies. Based on preliminary field surveys, we had presumed that P. lama might have given up its reproductive division of labour, i.e. workers would be able to produce males as well as workers and females parthenogenetically. In this study, this hypothesis was disproved: Polyrhachis lama workers cannot be fertilized and are only able to produce males. In the host–parasite association originating from nests possessing a P. lama queen, workers penetrate surrounding Diacamma sp. nests, carrying brood for rearing within these satellite nests. In this peculiar way, a single P. lama colony is able to exploit several Diacamma sp. colonies simultaneously.  相似文献   
964.
Dead wood provides a huge terrestrial carbon stock and a habitat to wide-ranging organisms during its decay. Our brief review highlights that, in order to understand environmental change impacts on these functions, we need to quantify the contributions of different interacting biotic and abiotic drivers to wood decomposition. LOGLIFE is a new long-term ‘common-garden’ experiment to disentangle the effects of species’ wood traits and site-related environmental drivers on wood decomposition dynamics and its associated diversity of microbial and invertebrate communities. This experiment is firmly rooted in pioneering experiments under the directorship of Terry Callaghan at Abisko Research Station, Sweden. LOGLIFE features two contrasting forest sites in the Netherlands, each hosting a similar set of coarse logs and branches of 10 tree species. LOGLIFE welcomes other researchers to test further questions concerning coarse wood decay that will also help to optimise forest management in view of carbon sequestration and biodiversity conservation.  相似文献   
965.
966.
This study aimed to analyse the influence of amnio-infusion on superior mesenteric Doppler velocimetry and to correlate Doppler data with outcome in fetuses presenting with gastroschisis. Umbilical and intra- and extra-abdominal superior mesenteric artery Doppler velocimetry was measured prospectively before and after amnio-infusion in fetuses with gastroschisis. Doppler index values and changes were correlated with the following outcome parameters: importance of fibrous coating, duration of hospitalization in the neonatal intensive care unit, total duration of hospitalization, duration of parenteral feeding, duration of ventilatory assistance, and the interval to initiation of oral feeding. A significant improvement of diastolic flow was observed in the extra-abdominal superior mesenteric artery with amnio-infusion. No similar change was seen in the intra-abdominal superior mesenteric or in the umbilical artery. Pre-amnioinfusion extra-abdominal mesenteric Doppler index was correlated with maximal diameter of exteriorized bowel and slightly with duration of hospitalization in the neonatal intensive care unit, but no other relation between Doppler index and outcome parameter could be ascertained. Amnio-infusion induces modifications in the vascularization of exteriorized bowel in gastroschisis. This could partly explain the beneficial effect of this procedure on fetal gut. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
967.
于1998年6月在塘沽港附近水域采集贻贝(Mytilus edulis),经试验室培养驯化后作为试验材料,研究了三丁基氯化锡(TBTC0和三苯基氯化锡(TPTC)的累积效应及其对贻贝的毒性影响。结果表明,在累积效应试验中,TBTC及TPTC对贻贝的半致死浓度LC50分别为3.5μg/dm^3和5.0μg/dm^3,当TBTC浓度达2.0μg/dm^3时,贻贝的成活率开始降低,实验还表明,TPT对贻贝的毒性效应与TBT相近。  相似文献   
968.
The biophysical features of small islands (SI) distinguish them from other territories; isolation, small size and several anthropogenic pressures reduce the resilience of ecosystems and increase their vulnerability to global changes. Many SI have a shortage of infrastructures, institutions and technical/financial resources that hinder planning and require different integrated solutions. In Portugal, the National Ecological Reserve (NER) is legally binding for spatial planning instruments. It aims to defend natural values and areas of ecological value, or sensibility, or susceptible to natural hazards. However, the criteria for the design of NER are strictly set for mainland territory, not taking into account specific features of small islands. A case study of the Azores Archipelago is used to demonstrate that spatial planning instruments should be adapted to island contexts. Such adaptation will increase the effectiveness of their implementation in relation to the protection of natural resources, stability of biophysical structures and prevention of natural hazards. Observing the main differences between mainland and the Azores Archipelago it is possible to define a methodological transposition of the NER aims and goals into an island context. This approach is an answer to the constraints in effective adaptation of spatial planning instruments for islands.  相似文献   
969.
Mainstream literature on climate change concentrates overwhelmingly on technological solutions for this global long-term problem, while a change towards climate-friendly behaviour could play a role in emission reduction and has received little attention. This paper focuses on the potential climate mitigation by behavioural change in the European Union (EU) covering many behavioural options in food, mobility and housing demand which do not require any personal up-front investment. We use the Global Change Assessment Model (GCAM), capturing both their direct and indirect implications in terms of greenhouse gas emissions. Our results indicate that modest to rigorous behavioural change could reduce per capita footprint emissions by 6 to 16%, out of which one fourth will take place outside the EU, predominantly by reducing land use change. The domestic emission savings would contribute to reduce the costs of achieving the internationally agreed climate goal of the EU by 13.5 to 30%. Moreover, many of these options would also yield co-benefits such as monetary savings, positive health impacts or animal wellbeing. These results imply the need for policymakers to focus on climate education and awareness programs more seriously and strategically, making use of the multiple co-benefits related with adopting pro-environmental behaviour. Apart from that, the relevance of behavioural change in climate change mitigation implies that policy-informing models on climate change should include behavioural change as a complement or partial alternative to technological change.  相似文献   
970.
The hydrothermal carbonization of sewage sludge has been studied as an alternative technique for the conversion of sewage sludge into value-added products, such as soil amendments. We tested the toxicity of biosolid hydrochar (Sewchar) to earthworms. Additionally, the toxicity of Sewchar process water filtrate with and without pH adjustment was assessed, using brine shrimps as a model organism. For a Sewchar application of 40 Mg ha?1, the earthworms significantly preferred the side of the vessel with the reference soil (control) over side of the vessel with the Sewchar treatments. There was no acute toxicity of Sewchar to earthworms within the studied concentration range (up to 80 Mg ha?1). Regarding the Sewchar process water filtrate, the median lethal concentration (LC50) to the shrimps was 8.1% for the treatments in which the pH was not adjusted and 54.8% for the treatments in which the pH was adjusted to 8.5. The lethality to the shrimps significantly increased as the amount of Sewchar process water filtrate increased. In the future, specific toxic substances in Sewchar and its process water filtrate, as well as their interactions with soil properties and their impacts on organisms, should be elucidated. Additionally, it should be identified whether the amount of the toxic compounds satisfies the corresponding legal requirements for the safe application of Sewchar and its process water filtrate.  相似文献   
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