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111.
Valuing water quality in China: purpose, approach and policy   总被引:12,自引:0,他引:12  
1 Introduction:heavygrowthandlightregulation(theTVIEsector)InChina,asinmanyrapidlydevelopingcountries,therearerapidchangesintheenvironmentoccurring.ThecaseofwaterqualityisanimportantoneasChina○swaterqualityhasdeterioratedsignificantlysince1980underth…  相似文献   
112.
The diets of 4 species of asteroids were observed for `9 months on the piles of a pier at Rapid Bay, South Australia.Coscinasterias calamaria (Gray) fed on molluscs, crustaceans and moribund items.Patiriella brevispina H.L. Clark fed on compound ascidians, sponges and moribund items.Tosia australis Gray andPetricia vernicina (Lamarck) ate mainly sponges, bryozoans and compound ascidians. A short-term (6 months) caging experiment showed that 5 common species of sessile animals-3 sponges and 2 compound ascidians-were significantly reduced by seastar predation. Nevertheless, the amount eaten, considered with seastar densities and distributions, indicates that the seastars are unimportant in influencing the utilization of space by sessile fauna. From comparing caged and uncaged controls, we tentatively suggest that other predators are also unimportant, and that competition for substrate space and for access to the water column is (and, has been during the evolution of these sessile organisms) far more influential.  相似文献   
113.
Previous attempts to determine palaeoenvironmental preferences in dinosaurs have generally been qualitative assessments based upon data from restricted geographical areas. Here, we use a global database of Cretaceous herbivorous dinosaurs to identify significant associations between clades and broad palaeoenvironmental categories (‘terrestrial’, ‘coastal’, ‘marine’). Nodosaurid ankylosaurs and hadrosaurids show significant positive associations with marine sediments, while marginocephalians (Ceratopsia, Pachycephalosauria), saurischians (herbivorous theropods, Sauropoda) and ankylosaurid ankylosaurs are significantly positively associated with terrestrial sediments. These results provide quantitative support for the hypothesis that some clades (Nodosauridae, Hadrosauridae) were more abundant in coastal and/or fluvial environments, while others (e.g. Marginocephalia, Ankylosauridae) preferentially inhabited more distal environments. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at  相似文献   
114.
This project was desinged to confirm the temporal consistency of inter-site differences in recruitment of an intertidal gastropod, and to test the hypothesis that these differences are accounted for by differences in shore topography. Annual recruitment of the intertidal sanil Nassarius pauperatus (Lamarck) was estimated at two sandflats in Gulf St Vincent, South Australia, over a period of 12 yr (1979 to 1990). At one sandflat the gradient was slight, the zone containing N. pauperatus was wide, and there were extensive pools of water at low tide, whilst at the other sandflat the gradient was steeper, the zone containing N. pauperatus was narrower, and there were fewer or no pools. Although recruitment at both sites varied temporally, the density of recruits was always higher at the first site. These data, together with data covering 10 yr (1981–1990) from a sandflat where the gradient of the substratum was decreasing due to accretion of sediment, suggest that shore topography is an important determinant of relative recruitment for N. pauperatus in South Australia.  相似文献   
115.
Sea-level rise involves increases in the coastal processes of inundation and erosion which are affected by a complex interplay of physical environmental parameters at the coast. Many assessments of coastal vulnerability to sea-level rise have been detailed and localised in extent. There is a need for regional assessment techniques which identify areas vulnerable to sea-level rise. Four physical environmental parameters – elevation, exposure, aspect and slope, are modeled on a regional scale for the Northern Spencer Gulf (NSG) study area using commonly available low-resolution elevation data of 10 m contour interval and GIS-based spatial modeling techniques. For comparison, the same parameters are modeled on a fine-scale for the False Bay area within the NSG using high-resolution elevation data. Physical environmental parameters on the two scales are statistically compared to coastal vulnerability classes as identified by Harvey et al. [1] using the Spearman rank-correlation test and stepwise linear regression. Coastal vulnerability is strongly correlated with elevation and exposure at both scales and this relationship is only slightly stronger for the high resolution False Bay data. The results of this study suggest that regional scale distributed coastal process modeling may be suitable as a first cut in assessing coastal vulnerability to sea-level rise in tide-dominated, sedimentary coastal regions. Distributed coastal process modeling provides a suitable basis for the assessment of coastal vulnerability to sea-level rise of sufficient accuracy for on-ground management and priority-setting on a regional scale.  相似文献   
116.
Community‐based conservation programs in developing countries are often based on the assumption that heteronomous motivation (e.g., extrinsic incentives such as economic rewards and pressure or coercion to act) will incite local communities to adopt conservation behaviors. However, this may not be as effective or sustainable as autonomous motivations (e.g., an intrinsic desire to act due to inherent enjoyment or self‐identification with a behavior and through freedom of choice). We analyzed the comparative effectiveness of heteronomous versus autonomous approaches to community‐based conservation programs through a case study of Sumatran orangutan (Pongo abelii) conservation in 3 villages in Indonesia. Each village had a different conservation program design. We surveyed people (n = 240) to determine their motivations for and behavior changes relative to orangutan and orangutan habitat (forest) protection. Heteronomous motivations (e.g., income from tourism) led to greater self‐reporting of behavior change toward orangutan protection. However, they did not change self‐reported behavior toward forest (i.e., orangutan habitat) protection. The most effective approach to creating self‐reported behavior change throughout the community was a combination of autonomous and heteronomous motivations. Individuals who were heteronomously motivated to protect the orangutan were more likely to have changed attitudes than to have changed their self‐reported behavior. These findings demonstrate that the current paradigm of motivating communities in developing countries to adopt conservation behaviors primarily through monetary incentives and rewards should consider integrating autonomous motivational techniques that promote the intrinsic values of conservation. Such a combination has a greater potential to achieve sustainable and cost‐effective conservation outcomes. Our results highlight the importance of using in‐depth sociopsychological analyses to inform the design and implementation of community‐based conservation programs.  相似文献   
117.
We compared root responses of the Ni-hyperaccumulator plant Berkheya coddii Rossler with the non-accumulator plant Cicer arietinum L. to Ni heterogeneity in soil. We grew plants in growth containers filled with control soil, homogeneously spiked, and heterogeneously spiked soil with Ni concentrations of 62 and 125 mg kg?1. Neutron radiography (NR) was used to observe the root distribution and the obtained images were analysed to reveal the root volumes in the spiked and unspiked segments of the growth container. There was no significant difference in root distribution pattern of B. coddii among different concentrations of Ni. Unlike B. coddii, the roots of C. arietinum initially grew into the spiked segments. However, the later developing roots did not penetrate the spiked segment suggesting an avoidance strategy. Our results indicate that, B. coddii does not forage towards the Ni-rich patches, although presence of Ni in soil changes its root morphology.  相似文献   
118.
This review summarizes the status of genetic laboratory testing in Prader–Willi syndrome (PWS) with different genetic subtypes, most often a paternally derived 15q11–q13 deletion and discusses benefits and limitations related to prenatal screening. Medical literature was searched for prenatal screening and genetic laboratory testing methods in use or under development and discussed in relationship to PWS. Genetic testing includes six established laboratory diagnostic approaches for PWS with direct application to prenatal screening. Ultrasonographic, obstetric and cytogenetic reports were summarized in relationship to the cause of PWS and identification of specific genetic subtypes including maternal disomy 15. Advances in genetic technology were described for diagnosing PWS specifically DNA methylation and high-resolution chromosomal SNP microarrays as current tools for genetic screening and incorporating next generation DNA sequencing for noninvasive prenatal testing (NIPT) using cell-free fetal DNA. Positive experiences are reported with NIPT for detection of numerical chromosomal problems (aneuploidies) but not for structural problems (microdeletions). These reports will be discussed along with future directions for genetic screening of PWS. In summary, this review describes and discusses the status of established and ongoing genetic testing options for PWS applicable in prenatal screening including NIPT and future directions for early diagnosis in PWS. © 2016 John Wiley & Sons, Ltd.  相似文献   
119.
Mainstreaming represents an integrated, cross government agency approach to incorporating an issue into programmes and policies. Mainstreaming of resource efficiency and sustainable consumption and production (SCP and RE) has been identified to be essential to ensuring the development of policies, programmes, actions and initiatives with a wider reaching set of outcomes than if these were to be undertaken on their own. This paper outlines a guidance framework which was developed to support practitioners, champions and UN support teams on mainstreaming of SCP and RE. The framework is based on the programmatic approach to environmental mainstreaming which has been developed through wide-ranging experience on other environment and poverty-environment related topics. The approach presented here is not linear, and each of the elements requires ongoing evaluation and updating. In addition, it is identified that mainstreaming of SCP and RE should form part of overall environmental mainstreaming efforts. Furthermore, unless a country has already developed a national SCP programme, the development of such a programme and the mainstreaming process discussed in this current document should be done in parallel, not as separate processes.  相似文献   
120.
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