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Spatial information in ecosystem service assessment: data applicability in the cascade model context
Harri Tolvanen Mia Rönkä Petteri Vihervaara Matti Kamppinen Céline Arzel Nina Aarras 《Journal of Land Use Science》2016,11(3):350-367
Spatial information and geographical information systems (GISs) are widely used in ecosystem service research, but both the information and the methods need to be properly understood in order to make coherent analyses. We discuss the practical challenges of incorporating spatial data to ecosystem service assessment in an agricultural landscape and apply the ecosystem service cascade model to put different data into context. We review the prerequisites and practices for successful ‘ecosystem service GIS’ and provide a structured view of the information and data needed in the assessment of ecosystem services at a regional scale. Due to the heterogeneity of the spatial data, the regional characteristics should be considered in environmental decision-making through ethnographic research on local expertise to make optimal choices in using spatial information. 相似文献
194.
Peter S. Murdoch Jill S. Baron Timothy L. Miller 《Journal of the American Water Resources Association》2000,36(2):347-366
ABSTRACT: Data from long‐term ecosystem monitoring and research stations in North America and results of simulations made with interpretive models indicate that changes in climate (precipitation and temperature) can have a significant effect on the quality of surface waters. Changes in water quality during storms, snowmelt, and periods of elevated air temperature or drought can cause conditions that exceed thresholds of ecosystem tolerance and, thus, lead to water‐quality degradation. If warming and changes in available moisture occur, water‐quality changes will likely first occur during episodes of climate‐induced stress, and in ecosystems where the factors controlling water quality are sensitive to climate variability. Continued climate stress would increase the frequency with which ecosystem thresholds are exceeded and thus lead to chronic water‐quality changes. Management strategies in a warmer climate will therefore be needed that are based on local ecological thresholds rather than annual median condition. Changes in land use alter biological, physical, and chemical processes in watersheds and thus significantly alter the quality of adjacent surface waters; these direct human‐caused changes complicate the interpretation of water‐quality changes resulting from changes in climate, and can be both mitigated and exacerbated by climate change. A rigorous strategy for integrated, long‐term monitoring of the ecological and human factors that control water quality is necessary to differentiate between actual and perceived climate effects, and to track the effectiveness of our environmental policies. 相似文献
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The distribution of phenotypic and genetic variation across environments can provide insights into local adaptation. The tropical sea anemone Condylactis gigantea inhabits a broad spectrum of coral-reef habitats and displays a variety of phenotypes, particularly with respect to color. At the coast of Discovery Bay, Jamaica, individuals with either pink or green tentacle tips show distinct distributions. Pink morphs are more abundant in the lagoon and in deeper areas, while green morphs are more abundant in the forereef and in shallower areas. We use DNA sequence data (ITS1-5.8S) to investigate if variation in color is associated with genetic differentiation in lagoon and forereef habitats about 5 km apart. Population genetic analyses reveal two distinct ITS1-5.8S variants, which differ in relative frequency. The two variants are present in both habitats, but a dearth of intermediates suggests reduced gene flow. In the lagoon, but not the forereef, ITS variants show an association with color. In order to address the potential ecological significance of color, we study UV absorbance and UV acclimatization capacities of pink and green color morphs in the lagoon. Color morphs differed significantly in UV-B absorbance. These results suggest genetic and ecological differentiation in the face of gene flow over short distances.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
197.
The wartbiter spermatophore and its effect on female reproductive output (Orthoptera: Tettigoniidae,Decticus verrucivorus) 总被引:3,自引:0,他引:3
Summary Male wartbiters Decticus verrucivorus transfer elaborate spermatophores to females during copulation. The spermatophore is attached externally to the female's genitalia and consists of two parts: a large, gelatinous, sperm-free portion, the spermatophylax, eaten by the female after mating; and a sperm-containing ampulla, eaten after the spermatophylax has been consumed. Since females take longer to eat larger spermatophylaxes, the duration of ampulla attachment is positively correlated with spermatophylax size. Two series of experiments were carried out, one in which the size of the spermatophylax consumed by females and the duration of ampulla attachment were manipulated in concert and another in which they were manipulated independently. Some females were also maintained on a protein-free diet and either supplied with or deprived of spermatophylax material. The amount of protein in the diet, but not the amount of spermatophylax material consumed, influenced female longevity, lifetime fecundity, and egg weight. When females were deprived of the spermatophylax, an experimental increase in the duration of ampulla attachment induced longer periods of unreceptivity in females after mating, a more rapid onset of oviposition, and an increased oviposition rate. Consequently, the number of eggs laid by females during their nonreceptive refractory periods increased significantly with increasing duration of ampulla attachment up to 180 min; however, there was no significant increase in the number of eggs laid beyond 180 min of ampulla attachment. This closely corresponds to an ampulla attachment duration of 188 min expected when a male transfers a natural spermatophylax of mean size to the female. These results suggest that the amount of ejaculate transferred to the female, and not the amount of spermatophylax material per se, is the factor controlling female receptivity and oviposition behavior. Since we did not detect any effect of spermatophylax consumption on female fecundity or egg weight, we conclude that the spermatophylax of D. verrucivorus functions primarily as a sperm protection device rather than as a form of male parental investment. 相似文献
198.
Ashley K Song R Esche CA Schlecht PC Baron PA Wise TJ 《Journal of environmental monitoring : JEM》1999,1(5):459-464
Recent studies have demonstrated the utility of ultrasonic extraction (UE), followed by portable anodic stripping voltammetry (ASV), for the on-site determination of lead in environmental and industrial hygiene samples. The aim of this work was to conduct an interlaboratory evaluation of the UE-ASV procedure, with a goal of establishing estimates of method performance based on results from collaborative interlaboratory analysis. In this investigation, performance evaluation materials (PEMs) with characterized lead concentrations were used for interlaboratory testing of the UE-ASV procedure. The UE-ASV protocol examined has been promulgated in the form of two separate national voluntary consensus standards (one for UE and another for electroanalysis, which includes ASV). The PEMs consisted of characterized and homogenized paints, soils, and dusts (the last of which were spiked onto wipes meeting national voluntary consensus standard specifications), and air filter samples (mixed cellulose ester membrane) generated using characterized paints within an aerosol chamber. The lead concentrations within the PEMs were chosen so as to bracket pertinent action levels for lead in the various sample matrices. The interlaboratory evaluation was conducted so as to comply with an applicable national voluntary consensus standard that can be used to estimate the interlaboratory precision of a given analytical test method. Based on the analytical results reported by the participating laboratories, relative standard deviations (RSDs) for repeatability and reproducibility were computed for three different lead contents of the four PEMs. RSDs for repeatability were 0.019-0.100 for paints; 0.030-0.151 for soils; 0.085-0.134 for dust wipes; and 0.095-0.137 for air filters. RSDs for reproducibility were 0.127-0.213 for paints; 0.062-0.162 for soils; 0.085-0.134 for dust wipes; and 0.114-0.220 for air filters. With the exception of one of the air filter samples and one of the paint samples, the precision estimates were within the +/- 20% precision requirement specified in the US Environmental Protection Agency National Lead Laboratory Accreditation Program (NLLAP). The results of this investigation illustrate that the UE-ASV procedure is an effective method for the quantitative measurement of lead in the matrices evaluated in this study. 相似文献
199.
农村生活污水处理技术 总被引:2,自引:0,他引:2
农村城市化发展迅速,而农村水污染情况日益严重,已对农村地区的水体、土地等自然环境产生严重影响。为建立和谐新农村,保障农村生活质量提高,缩小城乡差距,必须重视农村水源安全。本文就农村生活污水处理技术进行讨论,为农村发展提供参考。 相似文献