排序方式： 共有38条查询结果，搜索用时 15 毫秒
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Deidda Gian Piero Díaz de Alba Patricia Rodriguez Giuseppe Vignoli Giulio 《Mathematical Geosciences》2020,52(7):945-970
Mathematical Geosciences - Frequency-domain electromagnetic instruments allow the collection of data in different configurations, that is, varying the intercoil spacing, the frequency, and the... 相似文献
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Influence of transient storage on stream nutrient uptake based on substrata manipulation 总被引：3，自引：0，他引：3
Alba Argerich Eugènia Martí Francesc Sabater Roy Haggerty Miquel Ribot 《Aquatic Sciences - Research Across Boundaries》2011,73(3):365-376
Quantification of the transient storage zone (As) has become critical in stream biogeochemical studies addressed to examine factors controlling nutrient uptake. It is expected
that higher As may enhance the interaction between nutrients and biota and thus, increase nutrient uptake. However, results from the literature
are controversial. We hypothesized that besides of the size of As, the intrinsic physical and biological characteristics of stream structures that generate As are also relevant for nutrient uptake. We performed 24 additions of phosphate, ammonium, and chloride in four reaches of
a man-made channel where we introduced three types of naturally colonized substrata packs (mud, sand and cobbles) to modify
As. We estimated ammonium and phosphate uptake coefficients in both the main channel and As using a solute transport model (OTIS-P) and compared the results among reaches with different substrata types. The introduction
of substrata packs decreased water velocity and increased As similarly among treatments. Nutrient uptake coefficients in the main channel were similar among reaches with different type
substrata packs; however, nutrient uptake coefficients measured in As differed among them as well as the ratio between ammonium and phosphorus uptake coefficients in As, which were 1.6 in reaches with mud packs and 0.02 in reaches with sand or cobble packs. Results obtained in this study suggest
that the contribution of As in nutrient uptake not only depends on the size of As but on the type of materials used to increase As, and thus, have biogeochemical implications on restoration projects aimed to modify channel morphology. 相似文献
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Pelayo Salinas-de-León Alba Costales-Carrera Stephen Zeljkovic David J. Smith James J. Bell 《Estuarine, Coastal and Shelf Science》2011
Recruitment is a key factor driving the population dynamics of scleractinian corals, but despite its importance, we still have a poor understanding of recruitment processes in the Coral triangle region, which contains the most biodiverse marine ecosystems in the world. This study aimed to compare settlement rates to artificial settlement panels with cleared areas of natural reef in order to assess whether panels are a suitable indicator of natural coral settlement rates. We recorded coral settlement rates to panels made of two different materials (concrete and terracotta), attached to the reef at two different orientations (vertical and horizontal), and compared these settlement rates to those on cleared areas of natural reef positioned on vertical reef walls, over a 12 month period. We examined settlement rates at four sites in the Wakatobi National Marine Park, south-east Sulawesi, Indonesia; two reefs were light-limited, highly sedimented sites with low coral cover (<10%) and two had moderate coral cover (approx. 40%) and lower sedimentation rates. Panels were directly attached to the reef at 6–7 m depth. The number of coral spat per tile ranged from 0 to 34 and no significant differences were reported between the settlement rates to cleared natural reef areas and settlement panels. Significantly higher numbers of spat settled on the cryptic (back) side of the panels, while no significant difference was found between settlement rates to the different panel materials, or between the different orientations or any combination of these two factors. There is, however, a significant difference in the settlement rates between sites, for both settlement panels and permanent cleared areas, with higher settlement rates at the sites with higher live coral cover. We conclude that both concrete and terracotta panels yield similar settlement rates, and orientation makes no difference to settlement rates when panels are directly attached to the reef. Our results demonstrate that artificial substrata provide comparable settlement rate data to natural substrata and therefore are suitable for monitoring coral settlement rates in the future. 相似文献
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Wendy R. Eisner Jessica Jelacic Chris J. Cuomo Changjoo Kim Kenneth M. Hinkel Dorin Del Alba 《Transactions in GIS》2012,16(1):17-37
A traditional knowledge “Iñupiaq Web GIS”, based on a five‐year study and containing observations and environmental knowledge of Iñupiat communities indigenous to Arctic Alaska, was incorporated into a Web‐based platform. The website, “Arctic Cultural Cartography,” was created to be an open portal through which the password‐protected “Iñupiaq Web GIS” could be accessed. We discuss the process of developing the web GIS including the incorporation of user‐friendly features such as links to interactive maps, video clips of interviews, discussion boards, and the integration of popular web interfaces such as Facebook. We also discuss short‐ and long‐term goals for the further development of the GIS, its potential as a sustainable, participatory online database for sharing pertinent ecological knowledge, and challenges in achieving optimal community involvement given constraints imposed by remote locations with limited bandwidth. 相似文献
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