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91.
There is a growing availability of climate change information, offered to scientists and policy makers through climate services. However, climate services are not well taken up by the policy-making and planning community. Climate services focus on primary impacts of climate change, e.g., the disclosure of precipitation and temperature data, and this seems insufficient in meeting their needs. In this paper, we argue that, in order to reach the spatial planning community, climate services should take on a wider perspective by translating climate data to policy-relevant indicators and by offering support in the design of adaptation strategies. We argue there should be more focus on translating consequences of climate change to land-use claims and subsequently discuss the validity, consequences and implications of these claims with stakeholders, so they can play a role in spatial planning processes where much of the climate adaptation takes place. The term Climate Adaptation Services is introduced as being a stepwise approach supporting the assessment of vulnerability in a wider perspective and include the design and appraisal of adaptation strategies in a multi-stakeholder setting. We developed the Climate Adaptation Atlas and the Climate Ateliers as tools within the Climate Adaptation Services approach to support decision-making and planning processes. In this paper, we describe the different steps of our approach and report how some of the challenges were addressed.  相似文献   
92.
Climate change impacts on individual species are various and range from shifts in phenology and functional properties to changes in productivity and dispersal. The combination of impacts determines future biodiversity and species composition, but is difficult to evaluate with a single method. Instead, a comparison of mutually independent approaches provides information and confidence in patterns observed beyond what may be achieved in individual approaches. Here, we carried out such comparison to assess which ecosystem types in the Netherlands appear most vulnerable to climate change impacts, as arising from changes in hydrology, nutrient conditions and dispersal limitations. We thus combined meta-analyses of species range shifts with species distribution modelling and ecohydrological modelling with expert knowledge in two respective impact studies. Both impact studies showed that nutrient-poor ecosystems and ecosystem types with fluctuating water tables—like hay meadows, moist heathlands and moorlands—seem to be most at risk upon climate change. A subsequent meta-analysis of species–environmental stress relations indicated that particularly endangered species are adversely affected by the combination of drought and oxygen stress, caused by fluctuating moisture conditions. This implies that adaptation measures should not only aim to optimise mean environmental conditions but should also buffer environmental extremes. Major uncertainties in the assessment included the quantitative impacts of vegetation-hydrology feedbacks, vegetation adaptation and interactions between dispersal capacity and traits linked to environmental selection. Once such quantifications become feasible, adaptation measures may be tailor-made and optimised to conserve vulnerable ecosystem types.  相似文献   
93.
The suitability of a single intertidal fish trap for the assessment of long-term trends in fish and epibenthic invertebrate relies upon the assumption of an on-average constant sampling fraction from the study population. This assumption was examined by comparing trends over years in five different traps within the study area. For some species, like cod, the traps showed more or less parallel fluctuations. This is in agreement with the assumption. However, for other species, like mackerel, the assumption was invalidated by distinct trends over years.Publication no. 62 of the project Applied Scientific Research Netherlands Institute for Sea Research (BEWON)  相似文献   
94.
U. Witte 《Marine Biology》1996,124(4):571-581
The examination of oogenesis and reproductive pattern in three deep-sea demosponge species from the foot of the Barents Sea continental slope (Norwegian Sea, 2300 m, 75°18N; 9°55E), Thenea abyssorum, Trichostemma sol and Tentorium semisuberites, suggests that sexual reproduction is triggered by the vertical flux of particulate organic carbon at least in one species. All three species examined reproduce sexually and proved to be oviparous and gonochoristic. A considerable number of asexually produced reproductive units was found in Thenea abyssorum, but owing to morphological details the origin of these buds is equivocal, and asexual reproduction is therefore judged to be of minor importance. Oogenesis in the three species can be divided into two developmental periods and does not differ greatly from processes known from shallow water species, except for the almost complete absence of nurse cells. For Thenea abyssorum a distinct seasonal reproductive cycle was found. The onset of yolk accumulation coincides precisely with a maximum in vertical particle flux as detected in sediment trap studies (von Bodungen et al. 1994). In addition, prior to yolk accumulation the sponge tissue appears almost empty, without storage units. Once yolk accumulation (i.e. the second growth period) has started, gamete development and release are completed within a few weeks. Thus sexual reproduction is an important reproductive mode in deep-sea sponges, which may be triggered by the pulsed input of POC to this food-limited environment, the energy-dependent process of yolk accumulation being the most sensitive process.  相似文献   
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The use of mid-infrared attenuated total reflectance (ATR) spectroscopy enables direct measurement of nitrate concentration in soil pastes, but strong interfering absorbance bands due to water and soil constituents limit the accuracy of straightforward determination. Accurate subtraction of the water spectrum improves the correlation between nitrate concentration and its nu3 vibration band around 1350 cm(-1). However, this correlation is soil-dependent, due mostly to varying contents of carbonate, whose absorbance band overlaps the nitrate band. In the present work, a two-stage method is developed: First, the soil type is identified by comparing the "fingerprint" region of the spectrum (800-1200 cm(-1)) to a reference spectral library. In the second stage, nitrate concentration is estimated using the spectrum interval that includes the nitrate band, together with the soil type previously identified. Three methods are compared for estimating nitrate concentration: integration of the nitrate absorbance band, cross-correlation with a reference spectrum, and principal component analysis (PCA) followed by a neural network. When using simple band integration, the use of soil specific calibration curves leads to determination errors ranging from 5.5 to 24 mg[N]/kg[dry soil] for the mineral soils tested. The cross-correlation technique leads to similar results. The combination of soil identification with PCA and neural network modeling improves the predictions, especially for soils containing calcium carbonate. Typical prediction errors for light non-calcareous soils are about 4 mg[N]/kg[dry soil], whereas for soils containing calcium carbonate they range from 6 to 20 mg[N]/kg[dry soil], which is less than four percent of the concentration range investigated.  相似文献   
98.
Environmental Science and Pollution Research - There are increasing worldwide concerns about the negative impacts of healthcare waste generated in hospitals, especially in low- and middle-income...  相似文献   
99.
Environmental Science and Pollution Research - Aquaculture has emerged as one of the world’s fastest-growing food industries in recent years, helping food security and boosting global...  相似文献   
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