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An ecosystem service is a benefit derived by humanity that can be traced back to an ecological process. Although ecosystem services related to surface water have been thoroughly described, the relationship between atmospheric water and ecosystem services has been mostly neglected, and perhaps misunderstood. Recent advances in land-atmosphere modeling have revealed the importance of terrestrial ecosystems for moisture recycling. In this paper, we analyze the extent to which vegetation sustains the supply of atmospheric moisture and precipitation for downwind beneficiaries, globally. We simulate land-surface evaporation with a global hydrology model and track changes to moisture recycling using an atmospheric moisture budget model, and we define vegetation-regulated moisture recycling as the difference in moisture recycling between current vegetation and a hypothetical desert world. Our results show that nearly a fifth of annual average precipitation falling on land is from vegetation-regulated moisture recycling, but the global variability is large, with many places receiving nearly half their precipitation from this ecosystem service. The largest potential impacts for changes to this ecosystem service are land-use changes across temperate regions in North America and Russia. Likewise, in semi-arid regions reliant on rainfed agricultural production, land-use change that even modestly reduces evaporation and subsequent precipitation, could significantly affect human well-being. We also present a regional case study in the Mato Grosso region of Brazil, where we identify the specific moisture recycling ecosystem services associated with the vegetation in Mato Grosso. We find that Mato Grosso vegetation regulates some internal precipitation, with a diffuse region of benefit downwind, primarily to the south and east, including the La Plata River basin and the megacities of Sao Paulo and Rio de Janeiro. We synthesize our global and regional results into a generalized framework for describing moisture recycling as an ecosystem service. We conclude that future work ought to disentangle whether and how this vegetation-regulated moisture recycling interacts with other ecosystem services, so that trade-offs can be assessed in a comprehensive and sustainable manner. 相似文献
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L. Arthur N. Line 《BMJ (Clinical research ed.)》1942,1(4231):193-194
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Six female and six male adult rhesus macaques were given sticks and nylon balls as an attempt at simple cage enrichment. A latin square design was used to compare behavior during separate 4-week periods with each object and during a control period with no object. Frequency and duration of 15 different behaviors were recorded. Resting was the most common activity which decreased slightly in duration when the stick or nylon ball was present (P less than 0.02). The mean duration of stick use was longer than that of the nylon ball (P less than 0.01). No other behaviors changed significantly, including the frequency of abnormal behaviors such as self-abuse, stereotypic acts, and bizarre postures. Generally, these objects were used infrequently and led to few changes in the behavior of singly-caged adult rhesus macaques. However, they did appear to stimulate activity for some individuals. 相似文献
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Serotyping of Campylobacter jejuni, Campylobacter coli, and Campylobacter laridis from domestic and wild animals. 总被引:4,自引:0,他引:4
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By using 50 unabsorbed antisera, we were able to serotype 272 (65.7%) of 414 thermotolerant campylobacters from wild and domestic animals, on the basis of heat-stable antigens identified by means of passive hemagglutination. Forty-two serotypes were recognized. The pattern of serotypes detected in the various animal species was compared to human clinical isolates by using the Czekanowski index (proportional similarity index). The highest degree of similarity to the clinical isolates was observed for the poultry isolates, followed by strains from wild birds, flies, and pigs (in order of decreasing similarity). The serotypes recovered most frequently from poultry (LAU 1 and LAU 2) were also most prevalent in Norwegian patients. In contrast, serotype LAU 35/44, the predominant porcine serotype, was never recovered from human clinical specimens. Flies captured in chicken farms and in piggeries harbored serotypes which were also commonly seen in chickens and pigs, respectively. Nine of the strains included in this study could not be ascribed to any defined species. All of these were resistant to nalidixic acid and did not produce H2S. 相似文献
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The distribution and abundance of Thelypteris limbosperma, Athyrium distentifolium, and Matteuccia struthiopteris are modelled statistically in relation to 14 environmental variables along the major climatic, topographic, and edaphic gradients in western Norway. The data are from 624 stands from which measurements or estimates of mean January and mean July temperatures, humidity, altitude, aspect, and slope are available. From 182 of these stands eight soil variables have also been measured. The species responses are quantified by two numerical methods: Gaussian logit regression and weighted averaging (WA) regression. The estimated WA optima suggest that A. distentifolium has an ecological preference for low July and January temperatures, high altitudes, and soils of low-medium pH and base content. The species shows statistically significant Gaussian responses with summer temperature, humidity (= Martonnes humidity index), altitude, slope, aspect, pH, cation exchange capacity, and base saturation with optima of 8.7 °C, 188.9, 1220 m, 28°, 29°, 4.8, 13.77 mEq 100 g dry soil-1, and 13.4%, respectively. These suggest that the occurrence and relative abundance of A. distentifolium are well predicted by summer temperature, topography, and soil pH and base status. T. limbosperma has WA optima that suggest that it favours moderately high winter and summer temperatures, high humidity, medium altitude, and soils of low pH and base content. It has significant Gaussian responses to summer temperature (optimum =12.6 °C), winter temperature (-1.8 °C), humidity (179.2), altitude (459.5 m), slope (22.5°), and Na (0.7 mg 100 g dry soil-1). These suggest that climatic factors, altitude, and slope are significant predictors for its occurrence and abundance. M. struthiopteris has high WA optima for summer temperature, pH, Ca, Mg, K, Na, cation exchange capacity (CEC), and base saturation, and a low optima for humidity and winter temperature. Of these, summer temperature (16.0 °C), Ca (63.1 mg 100 g dry soil-1), Mg (41.0 mg 100 g dry soil-1), K (23.6 mg 100 g dry soil-1), Na (5.0 mg 100 g dry soil-1), CEC (60.7 mEq 100 g dry soil-1), and base saturation (56.3%) have significant Gaussian logit responses, as do aspect (150.2°) and loss-on-ignition (9.4%). These results suggest that the occurrence and relative abundance of M. struthiopteris are well predicted by high soil base cations, a generally southern aspect, low organic content in the soil, and high July temperatures. 相似文献
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The aims of this paper are to detect floristic variation within different types of tall-fern dominated vegetation and to interpret these patterns in terms of environmental variables. Numerical approaches have been applied to a large and varied vegetational data-set with associated environmental data from stands dominated by Athyrium distentifolium, Thelypteris limbosperma , and Matteuccia struthiopteris in different parts of western Norway. The numerical procedures of two-way indicator species analysis, simple discriminant functions, and canonical correspondence analysis have been used, and the strengths and weaknesses of these as tools in discerning vegetational-environmental relationships are discussed. For each of the 96 quadrats investigated, 17 environmental variables were measured. The investigation shows that some of the observed differences in vegetational composition can be explained in terms of relatively simple soil and climatic variables measured for each quadrat. The ferns appear to be ecologically well separated. T. limbosperma-dominaled stands are mainly characterised by low soil fertility, high January temperature, and high humidity. A. distentifolium-dominated stands are associated with low winter temperatures, and M. struthiopteris-dominated stands have high soil fertility and high summer temperatures. 相似文献
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Young rhesus macaques housed in outdoor corn cribs and fed a commercially prepared primate diet became weak, depressed, were reluctant to move, and expressed locomotor abnormalities. Thirteen severely affected animals were hospitalized for evaluation. Physical examination disclosed swellings and instabilities involving the ends of long bones. Radiography confirmed physeal fractures in 11 of 13 animals. Affected bones included the distal femur, proximal humerus, distal tibia/fibula, and distal radius/ulna. Other, less obvious changes were noted on radiographs. Anemia was a consistent finding. Ascorbic acid deficiency was suspected and therapy was initiated that consisted of vitamin supplements, diet change, cage rest, and support bandages. Feed samples were submitted to a laboratory for analysis and were confirmed deficient in vitamin C. Follow-up radiographs showed large calcifying subperiosteal hematomas in epiphyseometaphyseal regions, consistent with a diagnosis of scurvy. Twelve of 13 animals recovered clinically. Subsequent radiographs documented improvement of initially severe angular deformities associated with displaced fractures. 相似文献
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