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21.
22.
Studies on the effect of genetically modified Bacillus thuringiensis (Bt) crops on true soil dwelling non-target arthropods are scarce. The objective of this study was to assess the influence of a 4-week exposure to two Bt maize varieties (Cry1Ab) Cascade and MEB307 on the collembolan Protaphorura armata. For comparison three non-Bt maize varieties, Rivaldo (isogenic to Cascade), Monumental (isogenic to MEB307) and DK242, and two control diets based on baker's yeast (uncontaminated and contaminated with Bt toxin Cry1Ab) were also tested. Due to a lower C:N ratio, individuals reared on yeast performed significantly better in all of the measured endpoints than those reared on maize. P. armata performed equally well when reared on two Bt and three non-Bt maize varieties. Although there were no negative effects of Bt maize in this experiment, we recommend future studies on Bt crops to focus on species interactions in long-term, multi-species experiments.  相似文献   
23.
Amid a growing global agenda, biodiversity conservation has embraced gender equity as a pillar of equitable and effective practice. Gender equity has become enshrined in the global environment and development agenda through global commitments, policy and funding. However, for various reasons, conservation biodiversity often takes a simplistic view of gender as synonymous with women or as a dualism between women and men. This narrow view risks promoting inequitable processes and ineffective outcomes. Deeper engagement with feminist theory, and feminist political ecology in particular, could help advance biodiversity conservation's approach to how gender is understood, framed and integrated. Engaging with lessons from feminist political ecology can help advance gender equity in conservation through attention to power dynamics, intersectionality, and subjectivity.  相似文献   
24.
Since 1990s, a systematic program to measure air toxics has been active in New York State with monitors located both in urban and rural areas. In this study we examined the spatial and temporal characteristics of benzene, a known human carcinogen that is emitted by many source categories. The analysis indicates that ambient concentration levels of benzene have decreased by as much as 60% over this period not only in the ozone non-attainment area of New York City that had the reformulated gas (RFG) requirements, but also over the rest of the state as well. Although the rate of decrease appears to have flattened out in recent years, the annual average concentration levels are found to be above the health risk threshold even at the remote location, Whiteface Mountain, suggesting the need for further reductions in benzene emissions.  相似文献   
25.
Vocal signaling can be an important component of vertebrate communication during social interactions. If vocalizations vary among individuals but are consistent within a given individual, they may be used to discriminate among individuals. In many species, territorial males use vocalizations to discriminate between neighbors and strangers and either respond more aggressively toward strangers relative to neighbors (“dear enemy” effect) or they respond more aggressively toward neighbors relative to strangers (“nasty neighbor” effect). In the greater prairie-chicken (Tympanuchus cupido), male vocalizations are an integral part of the display males produce on leks. We investigated whether male greater prairie-chickens discriminate among familiar individuals on their own territory, familiar individuals outside their normal territory and strangers from a nearby lek. Vocal characteristics varied among males, suggesting that vocalizations may potentially be used by prairie-chickens to identify individuals. Males responded to playback of prairie-chicken calls by vocalizing at a faster rate and approaching the playback speaker, but did not vary in their response to the vocalizations based on the identity of the caller. Our results suggest that variation is present among the vocalizations of individual male greater prairie-chickens, but males do not appear to discriminate among familiar individuals and strangers based solely on their “boom” vocalizations. Greater prairie-chicken vocalization likely functions as a way of announcing that a territory is occupied and defended, but it may also serve as a way of advertising to conspecifics or as a signal that is secondary to other forms of communication.  相似文献   
26.
Humpback whales (Megaptera novaeangliae) in the Southeastern Atlantic Ocean (International Whaling Commission ‘Breeding Stock B’—BSB) are distributed from the Gulf of Guinea to Western South Africa. Genetic data suggest that this stock may be sub-structured, but it remains unknown if this is due to reproductive segregation. This paper evaluates the spatial and temporal population structure of BSB humpback whales using a combination of maternally and bi-parentally inherited markers. The genetic differentiation that we identify in this study could be due to a combination of (1) spatial and/or temporal segregation on breeding grounds in the greater Gulf of Guinea, (2) the possibility of maternally inherited site fidelity to specific feeding grounds and (3) the use of two generalized but exclusive migratory routes (coastal and offshore) between feeding and breeding areas. Further, photo-identification and genetic sampling efforts in other areas of the Sub-Saharan Western Africa winter range and targeted deployment of satellite tags would help to clarify some of the apparent complexity in the population structure of animals biopsied in this region.  相似文献   
27.

Introduction

Falls in older Australians are a significant public health issue with one in three older people falling one or more times each year.

Method

Many fall prevention randomized controlled trials have been conducted in Australia as well as across the world.

Results

The findings of these studies now constitute a substantial evidence base that can provide direction for health and lifestyle interventions for preventing falls in older people. This research evidence has contributed to health policy in Australia to some extent, but is yet to be widely implemented into practice. This opinion piece overviews previous policy initiatives and describes a new Partnership research program funded by the Australian National Health and Medical Research Council (NHMRC), which seeks to further influence health policy and address the ongoing research-practice gap.  相似文献   
28.
We present a new methodology for database-driven ecosystem model generation and apply the methodology to the world's 66 currently defined Large Marine Ecosystems. The method relies on a large number of spatial and temporal databases, including FishBase, SeaLifeBase, as well as several other databases developed notably as part of the Sea Around Us project. The models are formulated using the freely available Ecopath with Ecosim (EwE) modeling approach and software. We tune the models by fitting to available time series data, but recognize that the models represent only a first-generation of database-driven ecosystem models. We use the models to obtain a first estimate of fish biomass in the world's LMEs. The biggest hurdles at present to further model development and validation are insufficient time series trend information, and data on spatial fishing effort.  相似文献   
29.
Improving the eco‐efficiency of products is gaining increasing attention within industry. Through eco‐efficiency, companies aim to reduce the environmental impact of their products throughout the entire life cycle, while at the same time creating promising market opportunities or reducing costs. This article describes how companies can integrate eco‐efficiency aspects into the product development process. © 2000 John Wiley & Sons, Inc.  相似文献   
30.
In 1998 the Washington State Legislature enacted the Watershed Planning Act, which encourages local governments to develop watershed plans using collaborative processes. Objectives of the statute are to address water resource and water quality issues, salmon habitat needs and to establish instream flows. This exploratory study sought to examine two aspects of how local governments are implementing the Act: challenges and benefits associated with collaborative watershed planning and the capacity of local governments to conduct collaborative watershed planning. Using documents and interview data from four cases, it was found that all planning groups experience similar challenges, although newer planning groups experienced more challenges than groups with previous planning experience. Challenges include issues surrounding the collaborative process, interagency co-ordination and trust. Local governments struggle with building capacity to plan, particularly in the areas of funding, technical expertise, incentives for participation, adequate time to conduct planning and questions regarding appropriate scale and scope of their planning efforts. Despite the challenges, collaborative watershed planning is well underway, with more than 37 planning units conducting planning under the Act.  相似文献   
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