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31.
This study presents the concentrations of about 50 metals and ions in 33 different brands of bottled waters on the Swedish market. Ten of the brands showed calcium (Ca) concentrations ≤10 mg L−1 and magnesium (Mg) levels <3 mg L−1, implying very soft waters. Three of these waters had in addition low concentrations of sodium (Na; <7 mg L−1), potassium (K; <3 mg L−1) and bicarbonate (HCO3 ≤31 mg L−1). These brands were collected from barren districts. Nine of the brands were collected from limestone regions. They showed increased Ca-levels exceeding 50 mg L−1 with a maximum of 289 mg L−1. Corresponding Mg-levels were also raised in two brands exceeding 90 mg L−1. Two soft and carbonated waters were supplemented with Na2CO3 and NaCl, resulting in high concentrations of Na (644 and 648 mg L−1) and chloride (Cl; 204 and 219 mg L−1). Such waters may make a substantial contribution to the daily intake of NaCl in high water consumers. The storage of carbonated drinking water in aluminum (Al) cans increased the Al-concentration to about 70 μg L−1. Conclusion As there was a large variation in the material as regards concentrations of macro-elements such as Ca, Mg, Na, K and Cl. Supplementation with salts, e.g., Na2CO3, K2 CO3 and NaCl, can lead to increased concentrations of Na, K and Cl, as well as decreased ratios of Ca/Na and larger ratios of Na/K. Water with high concentrations of e.g., Ca and Mg, may make a substantial contribution to the daily intake of these elements in high water consumers. Al cans are less suited for storage of carbonated waters, as the lowered pH-values may dissolve Al. The levels of potentially toxic metals in the studied brands were generally low.  相似文献   
32.
In butterflies and other insects, fecundity generally increases with female adult weight. Hence, most butterflies are essentially "capital breeders", because nutrients acquired during the larval stage are stored and subsequently used for egg production during the adult stage. However, in some species, males transfer a large nutritious ejaculate to the female at mating. These females can partly be characterized as "income breeders", and female mass can potentially be decoupled from fecundity to some extent. In the gift-giving green-veined white butterfly Pieris napi, it has been shown that female fecundity and longevity increase with number of matings and also that females mature at smaller size under poor food conditions compared to males. So it has been suggested that females can compensate for their smaller size through nuptial feeding. Here we test this hypothesis in P. napi by assessing female fecundity and longevity in relation to female mass and polyandry. The results showed no support for the hypothesis. Smaller females were not capable of increasing their mating rate to compensate for a low weight at eclosion. Instead, larger females remated sooner. Also, smaller females suffered from both a reduced daily and total fecundity compared to larger females and this decrease in fecundity was independent of female mating status, i.e. females allowed to mate only once and multiply mated females suffered to the same extent from their smaller size.  相似文献   
33.
Environmental conditions, primary production, and zooplankton populations were studied from May, 1969 to November, 1970 at one station in Kungsbacka Fjord, Sweden. The fjord, with an arca of 53 km2, is a moderately polluted estuary, with a small tidal range. Data for primary production and environmental parameters were correlated using Spearman's rank correlation coefficient. The annual rate of primary production in 1970 was about 100 gC·m-2. Carbon fixation was about 80 g·m-2 in May–November in1969 and 1970. The average monthly rate was highest in June, 1970, with 25 gC·m-2; about 15 gC·m-2 was recorded in August–October of both years. Carbon fixation by the phytoplankton was estimated to be about 2,800 tons in the whole fjord in 1970. The average fresh-water inflow to the fjord, amounting to about 13 m3·sec-1, added about 380 tons of organic carbon, 45 tons of nitrogen, and 4.5 tons of phosphorus per month. Primary production displayed strong correlation with temperature at different depths (P<0.05 to 0.001), indicating the sediments to be the most important nutrient source. A total of 19 holoplanktonic zooplankton species was identified, copepods being the dominant group. The highest zooplankton biomass, 800 to 900 mg·m-3, was recorded in June of both years. The production of copepods in May–October was about 1 gC·m-2 in both years. The total secondary production of the zooplankton was calculated as only 1.8 gC·m-2 in 1970.  相似文献   
34.
The maintenance of biodiversity by securing representative and well-connected habitat networks in managed landscapes requires a wise combination of protection, management, and restoration of habitats at several scales. We suggest that the integration of natural and social sciences in the form of "Two-dimensional gap analysis" is an efficient tool for the implementation of biodiversity policies. The tool links biologically relevant "horizontal" ecological issues with "vertical" issues related to institutions and other societal issues. Using forest biodiversity as an example, we illustrate how one can combine ecological and institutional aspects of biodiversity conservation, thus facilitating environmentally sustainable regional development. In particular, we use regional gap analysis for identification of focal forest types, habitat modelling for ascertaining the functional connectivity of "green infrastructures", as tools for the horizontal gap analysis. For the vertical dimension we suggest how the social sciences can be used for assessing the success in the implementation of biodiversity policies in real landscapes by identifying institutional obstacles while implementing policies. We argue that this interdisciplinary approach could be applied in a whole range of other environments including other terrestrial biota and aquatic ecosystems where functional habitat connectivity, nonlinear response to habitat loss and a multitude of economic and social interests co-occur in the same landscape.  相似文献   
35.
36.
Global greenhouse gas emissions from air travel (GHG-A) are on the rise, and projections point towards a rapid growth in the coming decades. This study aims to examine how local government (cities), addresses GHG-A in their Sustainable Energy Action Plans (SEAP). To fulfil this aim, over 200 SEAPs were analysed focusing on three issues: (1) Treatment of GHG-A in local emissions inventories; (2) Policy initiatives within this domain; and (3) The cities’ perceptions of the conflicts of interests. Results showed that more than half of the cities acknowledge the challenge of GHG-A, around one third include GHG-A in their emissions inventories, and more than one quarter have initiated policy interventions. To categorise these interventions, we have added a mode ‘governing by agenda setting’ to an existing analytical framework, ‘Modes of governing’. With their authority limited to the local setting, this mode of governing is a common channel for cities to push changes at higher levels.  相似文献   
37.
Disappearance rate constants are reported for the reductive transformation of 17 halogenated aliphatic hydrocarbons in anaerobic sediment-water samples. Statistical experimental design in combination with multivariate chemical characterization of their chemical properties was used to select the compounds. Degradation followed pseudo first-order kinetics through at least two half-lives for 15 of the 17 compounds. Of all the compounds investigated, 1,2,3-trichloropropane and dichloromethane were unique in that they were dehalogenated according to zero-order kinetics. Reductive dehalogenation was the sole transformation reaction taking place.  相似文献   
38.
ABSTRACT

Innovative climate governance in small-to-medium-sized structurally disadvantaged cities (SDCs) are assessed. Considering their deeply ingrained severe economic and social problems it would be reasonable to assume that SDCs act primarily as climate laggards or at best as followers. However, novel empirical findings show that SDCs are capable of acting as climate pioneers. Different types and styles of climate leadership and pioneership and how they operate within multi-level and polycentric governance structures are identified and assessed. SDCs seem relatively readily willing to adopt transformational climate pioneership styles to create ‘green’ jobs, for example, in the offshore wind energy sector and with the aim of improving their poor external image. However, in order to sustain transformational climate pioneership they often have to rely on support from ‘higher’ levels of governance. For SDCs, there is a tension between learning from each other’s best practice and fierce economic competition in climate innovation.  相似文献   
39.
40.
The adoption of a Climate Disaster Resilience Index in Chennai,India   总被引:1,自引:0,他引:1  
Results derived from the Climate Disaster Resilience Index (CDRI)—consisting of five dimensions (economic, institutional, natural, physical, and social), 25 parameters, and 125 variables—reflect the abilities of people and institutions to respond to potential climate‐related disasters in Chennai, India. The findings of this assessment, applied in the 10 administrative zones of the city, reveal that communities living in the northern and older parts of Chennai have lower overall resilience as compared to the flourishing areas (vis‐à‐vis economic growth and population) along the urban fringes. The higher resilience of communities along the urban fringes suggests that urbanisation may not necessarily lead to a deterioration of basic urban services, such as electricity, housing, and water. This indication is confirmed by a strong statistical correlation between physical resilience and population growth in Chennai. The identification of the resilience of different urban areas of Chennai has the potential to support future planning decisions on the city's scheduled expansion.  相似文献   
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