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481.
Alexander Zaporozec 《Journal of the American Water Resources Association》1972,8(6):1137-1143
In today's society the planned management of groundwater resources has played an increasingly greater role. One means of insuring the protection of groundwater quantity and quality is a regional zoning of groundwater resources. Regional zoning means to classify a given region with regard to hydrogeological characteristics and to evaluate and determine the possible use of each zone. The necessary assumption is the appropriate knowledge of geological structure (compiled in a geological map) and of hydrogeological conditions (compiled in a hydrogeological map). The basis for subdivision is a hydrogeological unit distinguished and delineated on the basis of lithological, stratigraphical, structural, and hydrogeological characteristics. It should have its own distinct hydrological system. The hydrogeological region is the basic unit. Regions may be grouped into larger units: hydrogeological provinces and realms. The subdivision of regions into hydrogeological zones, or subzones when applicable, forms the basis for a groundwater development plan. 相似文献
482.
David Alexander JC Gaillard Ilan Kelman Fausto Marincioni Edmund Penning‐Rowsell Dewald van Niekerk Lauren J. Vinnell 《Disasters》2021,45(1):5-18
Nowadays there are approximately 80 Anglophone journals that deal primarily with disaster risk reduction (DRR) and allied fields. This large array signals a sustained, if uneven, growth in DRR scholarship but also competition between the offerings of different publishers and institutions. The purpose of this article is first to summarise the development of academic publishing on DRR from its early beginnings to the present day. The paper then evaluates the current state of publishing in this field and discusses possible future trends. Next, it identifies some possible opportunities, challenges, expectations, and commitments for journal editors both within DRR and academia more broadly, including those that refer to changes in the use of terminology, the relentless increase in the number of papers submitted, the expansion and dangers of predatory journals, different peer review models, open access versus paywalls, citations and bibliography metrics, academic social networks, and copyright and distribution issues. 相似文献
483.
Melissa S. Gerald James Ayala Angelina Ruíz-Lambides Corri Waitt Alexander Weiss 《Die Naturwissenschaften》2010,97(1):89-96
Several primate species show sexual dichromatism with males displaying conspicuous coloration of the pelage or skin. Studies
of scrotal coloration in male vervet monkeys (Chlorocebus aethiops) suggest that it is an important intrasexual signal, with relatively dark, colourful males dominating paler males. To date,
no studies have examined the influence of male colour on intersexual social interactions in vervet monkeys. The primary goal
of the present study was to evaluate whether female vervet monkeys attend to male coloration. We experimentally introduced
females, housed with either “pale” or “dark” males, to stimulus males whose scrota were pale, dark, or pale but painted to
look dark. Overall, during introductions, females did not differ in time spent directing affiliative behaviour toward pale,
dark, and painted males; however, females, permanently housed with dark males, spent significantly more time directing affiliative
behaviour toward pale than painted males. When the stimulus male was pale, affiliative exchanges between males and females
were longer than when the stimulus male was painted. Home male colour was not related to female-initiated aggression. Home
male colour was also not related to male-initiated aggression, although painted stimulus males were more likely to initiate
aggression than pale stimulus males. These findings lead us to conclude that females pay attention to male coloration, but
do not bias their interactions toward males solely on the basis of natural male coloration. 相似文献
484.
Turanoceratops tardabilis from the Upper Cretaceous (Turonian) Bissekty Formation of Dzharakuduk, Uzbekistan, represents the first definite ceratopsid
dinosaur recorded from Asia. Reexamination of the original and study of newly collected material indicate that Turanoceratops has well-developed supraorbital horns and apparently lacks a nasal horn. Turanoceratops is more derived than the more or less coeval Zuniceratops from the Moreno Hill Formation of New Mexico in the presence of double-rooted teeth and of two or three teeth in each vertical
dental file. 相似文献
485.
Md Sarwar Hossain Sarah J. Pogue Liz Trenchard Alexander P. E. Van Oudenhoven Carla-Leanne Washbourne Evalyne W. Muiruri 《国际发展与全球生态学杂志》2018,25(3):249-261
We aimed to identify priority research questions in the field of biodiversity, ecosystem services and sustainability (BESS), based on a workshop held during the NRG BESS Conference for Early Career Researchers on BESS, and to compare these to existing horizon scanning exercises. This work highlights the need for improved data availability through collaboration and knowledge exchange, which, in turn, can support the integrated valuation and sustainable management of ecosystems in response to global change. In addition, clear connectivity among different research themes in this field further emphasizes the need to consider a wider range of topics simultaneously to ensure the sustainable management of ecosystems for human wellbeing. In contrast to other horizon scanning exercises, our focus was more interdisciplinary and more concerned with the limits of sustainability and dynamic relationships between social and ecological systems. The identified questions could provide a framework for researchers, policy makers, funding agencies and the private sector to advance knowledge in biodiversity and ES research and to develop and implement policies to enable sustainable future development. 相似文献
486.
Simon Lüderwald Kymberly Newton Katharina Heye Kristina Bitter Samuel Moeris Lena Benner Paul Böhm Josef Koch Alexander Feckler Mafalda Castro Andreas Erikkson 《Environmental Sciences Europe》2018,30(1):41
This commentary is an introduction for students to the Society of Environmental Toxicology and Chemistry (SETAC) and its Student Advisory Council (SAC). As young academics face challenges while trying to develop their careers, SETAC and the SAC help facilitate student involvement in the various communities within the society that can help to develop the students’ careers within the environmental sciences [e.g. the German Language Branch (GLB)]. This piece would also like to emphasize and pay homage to the continual cooperation between the SAC and the ESEU, which provides a scientific platform to communicate internationally and beyond the borders of SETAC, as well as offer heartfelt congratulations from the SAC to the GLB for their “20 Years SETAC GLB” and deep gratitude for their strong advocacy and support of the SAC. 相似文献
487.
Symbiotic bacteria from six Oscarella species (adults and embryos) collected in the Mediterranean Sea (O. lobularis, O. tuberculata, O. imperialis, O. microlobata, O. viridis) and the Sea of Japan (O. malakhovi) were investigated by scanning electron microscopy and transmission electron microscopy. In most cases, symbionts are rather
numerous. Each sponge species has a definite set of bacterial morphological types. All bacteria are extracellular. Symbionts
occupy the mesohyl of adult sponges or intercellular space in embryos and are often in contact with mesohylar filaments or
cells. Bacteria of some morphotypes have characteristic blebs. Most symbionts are gram-negative, and two types of bacteria
have traits of Archaea and one type of bacteria is similar to Planctomycetes. Data on morphology of bacterial symbionts can
be a good additional character for identification of Oscarella species, which have no skeleton. 相似文献
488.
Ximena E. Bernal Karin L. Akre Alexander T. Baugh A. Stanley Rand Michael J. Ryan 《Behavioral ecology and sociobiology》2009,63(9):1269-1279
We investigated the natural dynamics in a sexual signal that combines different call components and explored the role of call
complexity in sexual selection using a neotropical frog. Male túngara frogs, Physalaemus pustulosus, facultatively add up to seven short, multi-harmonic components (chucks) to the simple form of their calls (whines). Female
túngara frogs are preferentially attracted to whines with chucks over whines without chucks, and males also call more in response
to calls containing chucks. Because acoustic predators prefer complex calls, in the context of simple (no chucks) versus complex
(any number of chucks) calls, the variably complex call appears to have evolved in response to the opposing selective forces
of natural and sexual selection. There is no evidence, however, for the function of increasing the number of chucks within
complex calls. We tested two aspects of increasing call complexity: natural patterns of use of call types in males and how
both sexes respond to variation in multi-chuck calls. Males incrementally change call complexity by the addition or subtraction
of a single chuck and usually do not produce more than two chucks. Variation in call complexity, for calls with at least one
chuck, does not influence response calling in males or phonotaxis in females. Our results suggest that one reason for not
increasing call complexity beyond a single chuck is the diminishing effectiveness on the responses of both sexes.
This is a posthumous publication for A. Stanley Rand 相似文献
489.
Aline S. Turque Alexander M. Cardoso Cynthia B. Silveira Ricardo P. Vieira Flávia A. D. Freitas Rodolpho M. Albano Alessandra M. Gonzalez Rodolfo Paranhos Guilherme Muricy Orlando B. Martins 《Marine Biology》2008,155(2):135-146
In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated
bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic
particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were
retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction,
and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living
bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand,
some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate
bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl
matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to
particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial
communities are composed of both taxons shared by many sponge groups and by species-specific bacteria. 相似文献
490.
Pawel Wasowicz Alexander N. Sennikov Kristine B. Westergaard Katie Spellman Matthew Carlson Lynn J. Gillespie Jeffery M. Saarela Steven S. Seefeldt Bruce Bennett Christian Bay Stefanie Ickert-Bond Henry Vre 《Ambio》2020,49(3):693-703
We present a comprehensive list of non-native vascular plants known from the Arctic, explore their geographic distribution, analyze the extent of naturalization and invasion among 23 subregions of the Arctic, and examine pathways of introductions. The presence of 341 non-native taxa in the Arctic was confirmed, of which 188 are naturalized in at least one of the 23 regions. A small number of taxa (11) are considered invasive; these plants are known from just three regions. In several Arctic regions there are no naturalized non-native taxa recorded and the majority of Arctic regions have a low number of naturalized taxa. Analyses of the non-native vascular plant flora identified two main biogeographic clusters within the Arctic: American and Asiatic. Among all pathways, seed contamination and transport by vehicles have contributed the most to non-native plant introduction in the Arctic. 相似文献