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141.
James?C.?MakinsonEmail author Benjamin?P.?Oldroyd Timothy?M.?Schaerf Wandee?Wattanachaiyingcharoen Madeleine?Beekman 《Behavioral ecology and sociobiology》2011,65(5):945-958
The Red Dwarf honeybee (Apis florea) is one of two basal species in the genus Apis. A. florea differs from the well-studied Western Hive bee (Apis mellifera) in that it nests in the open rather than in cavities. This fundamental difference in nesting biology is likely to have implications
for nest-site selection, the process by which a reproductive swarm selects a new site to live in. In A. mellifera, workers show a series of characteristic behaviors that allow the swarm to select the best nest site possible. Here, we describe
the behavior of individual A. florea workers during the process of nest-site selection and show that it differs from that seen in A. mellifera. We analyzed a total of 1,459 waggle dances performed by 197 scouts in five separate swarms. Our results suggest that two
fundamental aspects of the behavior of A. mellifera scouts—the process of dance decay and the process of repeated nest site evaluation—do not occur in A. florea. We also found that the piping signal used by A. mellifera scouts to signal that a quorum has been reached at the chosen site, is performed by both dancing and non-dancing bees in
A. florea. Thus, the piping signal appears to serve a different purpose in A. florea. Our results illustrate how differences in nesting biology affect the behavior of individual bees during the nest-site selection
process. 相似文献
142.
Igor Linkov Sankar Basu Cathleen Fisher Nancy Jackson Adam C. Jones Maija M. Kuklja Benjamin D. Trump 《The Environmentalist》2016,36(4):331-334
Technology innovation is an increasingly globalized exercise with dramatic consequences for scientific and diplomatic goals alike, and requires enhanced participation and integration of scientists and science-minded diplomats within diplomatic missions to advance shared policy goals. This more general problem is addressed in the present article by focusing on recent collaborations between U.S. and German scientists, including several of the coauthors. 相似文献
143.
Boris?YatsaloEmail author Sergey?Gritsyuk Terry?Sullivan Benjamin?Trump Igor?Linkov 《The Environmentalist》2016,36(3):266-276
Emerging challenges of risk management, environmental protection, and land-use planning requires integration of stakeholder values and expert judgment. The process of decision making in situation of high uncertainty can be assisted through the use of decision support systems (DSSs). Such DSSs are often based on tools for spatial data representation (GIS) and environmental models that are integrated using multi-criteria decision analysis (MCDA). This paper presents DecernsMCDA implementing all major types of multi-criteria methods and tools (AHP, MAUT, Outranking) under the same user interface. In addition to providing ability for testing model uncertainty associated with selection of specific MCDA algorithms, DecernsMCDA implements new algorithms for parameter uncertainty analysis based on probabilistic approaches and fuzzy sets. The paper illustrates application of DecernsMCDA for selecting remedial alternative at radiologically contaminated sites. 相似文献
144.
Aaron S. Veenstra Benjamin A. Lyons Amy Fowler-Dawson 《Environmental Communication: A Journal of Nature and Culture》2016,10(3):322-336
ABSTRACTAlthough recent expansions in hydraulic fracking operations across the United States have led to greater news coverage and attention from the public, overall understanding remains fairly low. For some, relevant social identities, including environmental or political, may provide a short cut to becoming informed about fracking, or to determining what they believe about it and how that influences their positions on fracking policies. Social identity influence frameworks provide an approach to understanding the relationships between belief and identity, which this study investigates through its affiliational and attitudinal components. National survey data are used to model pathways from environmental and political identities to beliefs about risks associated with fracking. Environmental attitudes significantly predicted belief that fracking has health risks, and mediated a relationship from environmental group affiliation, but environmental information was not significant. Ideology had direct and indirect effects, through partisan media use, while partisanship had direct effects on beliefs about environmental risks. 相似文献
145.
Christopher Kuzdas Benjamin P. Warner Arnim Wiek Raffaele Vignola Mariel Yglesias Daniel L. Childers 《Sustainability Science》2016,11(2):231-247
Many new forms of water governance are emerging in response to economic and social needs and wants, as well as water-related problems such as scarcity, injustice, and conflict. However, there is little evidence on how sustainable these governance regimes are, which would be critical for making progress toward sustainable and just water governance. In this article, we present the results of a transdisciplinary multi-criteria sustainability assessment of alternative governance regimes for Guanacaste Province, Costa Rica. The assessment specifies differences between sustainable and unsustainable governance regimes, while also pinpointing how the current water governance regime performs in comparison to those alternatives. The findings indicate that those governance regimes with just and deliberative stakeholder involvement, secure groundwater reserves, and healthy dry tropical ecosystems were considered sustainable and just. In contrast, the current state of water governance was found to be at high risk of digressing toward unsustainable systems where rural communities lack rights and influence, where economies favor agro-industry and high impact tourism at the expense of rural livelihoods, and where water scarcity overwhelms weak governance. This assessment study clarifies water sustainability goals, asserts the need for transformational change, and offers a pragmatic foundation for actions toward sustainable water governance. 相似文献
146.
147.
Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho1
Benjamin T. Stratton Venakataramana Sridhar Molly M. Gribb James P. McNamara Balaji Narasimhan 《Journal of the American Water Resources Association》2009,45(6):1390-1408
Stratton, Benjamin T., Venakataramana Sridhar, Molly M. Gribb, James P. McNamara, and Balaji Narasimhan, 2009. Modeling the Spatially Varying Water Balance Processes in a Semiarid Mountainous Watershed of Idaho. Journal of the American Water Resources Association (JAWRA) 45(6):1390‐1408. Abstract: The distributed Soil Water Assessment Tool (SWAT) hydrologic model was applied to a research watershed, the Dry Creek Experimental Watershed, near Boise Idaho to investigate its water balance components both temporally and spatially. Calibrating and validating SWAT is necessary to enable our understanding of the water balance components in this semiarid watershed. Daily streamflow data from four streamflow gages were used for calibration and validation of the model. Monthly estimates of streamflow during the calibration phase by SWAT produced satisfactory results with a Nash Sutcliffe coefficient of model efficiency 0.79. Since it is a continuous simulation model, as opposed to an event‐based model, it demonstrated the limited ability in capturing both streamflow and soil moisture for selected rain‐on‐snow (ROS) events during the validation period between 2005 and 2007. Especially, soil moisture was generally underestimated compared with observations from two monitoring pits. However, our implementation of SWAT showed that seasonal and annual water balance partitioning of precipitation into evapotranspiration, streamflow, soil moisture, and drainage was not only possible but closely followed the trends of a typical semiarid watershed in the intermountain west. This study highlights the necessity for better techniques to precisely identify and drive the model with commonly observed climatic inversion‐related snowmelt or ROS weather events. Estimation of key parameters pertaining to soil (e.g., available water content and saturated hydraulic conductivity), snow (e.g., lapse rates, melting), and vegetation (e.g., leaf area index and maximum canopy index) using additional field observations in the watershed is critical for better prediction. 相似文献
148.
149.
Benjamin Jessup Jason Pappani 《Journal of the American Water Resources Association》2015,51(5):1408-1417
States and tribes are encouraged to use multiple biological assemblages in assessment of water bodies. An assessment index for each assemblage provides information on aspects of the aquatic resource that may be unique in terms of stressor sensitivity, stressor type, or ecological scale. However, assessment results relative to impairment thresholds can disagree among indices for an individual water body, leading to uncertain overall water‐body assessments. We explored options for combining stream indices for macroinvertebrates, fish, and habitat in ways that would yield the most consistent and sensitive results relative to established disturbance categories. Methods varied in the scoring or rating scales used to standardize each index value, the thresholds used to define impairment of aquatic life uses, and the ways of synthesizing multiple indices. The index compositing method that scores each index on a continuous scale and averages the scores after standardizing had superior accuracy, sensitivity, and precision. In addition, using the 25th quantile of reference sites instead of the 10th quantile resulted in a more balanced error rate among reference and degraded site categories. 相似文献
150.
Benjamin Felzer Preston Heard 《Journal of the American Water Resources Association》1999,35(6):1327-1339
ABSTRACT: Two general circulation models (GCMs) used in the U.S. national assessment of the potential consequences of climate variability and change (CGCM1 and HadCM2) show a large increase in precipitation in the future over the southwestern U.S., particularly during winter. This precipitation increase is an extension of a larger region of increased precipitation in the Pacific Ocean off the west coast of North America that is associated with a deepened and southward-shifted Aleutian Low, a weaker subtropical high, and warmer sea surface temperatures (SSTs). The models differ in their simulation of precipitation anomalies over the southeastern U.S., with CGCM1 showing drier conditions and HadCM2 showing wetter conditions in the future. While both models show decreased frequency of Atlantic storms, consistent with decreased meridional and land/sea temperature gradients, the more coastal position of the storm track in CGCM1 results in less precipitation than modern along the eastern seaboard of the U.S. During summer, differences in land surface models within the two GCMs sometimes lead to differences in soil moisture that feed back to the precipitation over land due to available moisture. 相似文献