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21.
The British Columbia Ministry of Forests’ “Aboriginal Rights and Title — Consultation Guidelines”, prepared in response to a Supreme Court of Canada decision on aboriginal rights and title, presents an interesting example of how common law influences provincial environmental policy. The policy addresses the British Columbia government’s fiduciary duty to First Nations and requires staff to consult with aboriginals during operational forestry planning. Adequate understanding of the policy is essential for lawful forest management. The Consultation Guidelines have become a key environmental policy in British Columbia.This evaluation will increase understanding of the Consultation Guidelines and aboriginal title for forest practitioners and policy makers. Within the context of a Vancouver Island case study, the policy is analyzed in view of the following criteria: effectiveness, efficiency, equity, and effort. Even though the policy is over 2 years old and the government is actively managing forests in an area under negotiation for treaty, the policy has yet to be implemented. As a result, aboriginal concerns about the long-term environmental and economic sustainability of current forest practices go unheeded. This situation potentially jeopardizes the government’s ability to address its fiduciary responsibilities to aboriginals, as defined in case law and the Canadian Constitution. 相似文献
22.
Kate M. Munson Richard M. Vogel John L. Durant 《Journal of the American Water Resources Association》2018,54(2):527-542
We investigate the sensitivity of phosphorus loading (mass/time) in an urban stream to variations in climate using nondimensional sensitivity, known as elasticity, methods commonly used by economists and hydrologists. Previous analyses have used bivariate elasticity methods to represent the general relationship between nutrient loading and a variable of interest, but such bivariate relations cannot reflect the complex multivariate nonlinear relationships inherent among nutrients, precipitation, temperature, and streamflow. Using fixed‐effect multivariate regression methods, we obtain two phosphorus models (nonparametric and parametric) for an urban stream with high explanatory power that can both estimate phosphorus loads and the elasticity of phosphorus loading to changes in precipitation, temperature, and streamflow. A case study demonstrates total phosphorus loading depends significantly on season, rainfall, combined sewer overflow events, and flow rate, yet the elasticity of total phosphorus to all these factors remains relatively constant throughout the year. The elasticity estimates reported here can be used to examine how nutrient loads may change under future climate conditions. 相似文献
23.
Physical and Chemical Connectivity of Streams and Riparian Wetlands to Downstream Waters: A Synthesis 下载免费PDF全文
Ken M. Fritz Kate A. Schofield Laurie C. Alexander Michael G. McManus Heather E. Golden Charles R. Lane William G. Kepner Stephen D. LeDuc Julie E. DeMeester Amina I. Pollard 《Journal of the American Water Resources Association》2018,54(2):323-345
Streams, riparian areas, floodplains, alluvial aquifers, and downstream waters (e.g., large rivers, lakes, and oceans) are interconnected by longitudinal, lateral, and vertical fluxes of water, other materials, and energy. Collectively, these interconnected waters are called fluvial hydrosystems. Physical and chemical connectivity within fluvial hydrosystems is created by the transport of nonliving materials (e.g., water, sediment, nutrients, and contaminants) which either do or do not chemically change (chemical and physical connections, respectively). A substantial body of evidence unequivocally demonstrates physical and chemical connectivity between streams and riparian wetlands and downstream waters. Streams and riparian wetlands are structurally connected to downstream waters through the network of continuous channels and floodplain form that make these systems physically contiguous, and the very existence of these structures provides strong geomorphologic evidence for connectivity. Functional connections between streams and riparian wetlands and their downstream waters vary geographically and over time, based on proximity, relative size, environmental setting, material disparity, and intervening units. Because of the complexity and dynamic nature of connections among fluvial hydrosystem units, a complete accounting of the physical and chemical connections and their consequences to downstream waters should aggregate over multiple years to decades. 相似文献
24.
Boyi Cheng Yi Wang Yumei Hua Kate V. Heal 《Frontiers of Environmental Science & Engineering》2021,15(4):73
25.
26.
Kate D. L. Umbers Nikolai J. Tatarnic Gregory I. Holwell Marie E. Herberstein 《Behavioral ecology and sociobiology》2013,67(3):439-447
Bright colours often communicate important information between conspecifics. In sexually dichromatic species where males exhibit bright colours, two hypotheses are often invoked to explain the function of the colour. First, if a male’s bright colour contains information about his quality, females may prefer brighter males. Equally, male colour may reliably provide other males with information about fighting ability or resource holding potential. In such circumstances, brighter males may win altercations and/or males may use rival colour to assess their likelihood of winning an interaction. In the chameleon grasshopper (Kosciuscola tristis), males but not females turn bright turquoise when their body temperature exceeds 25 °C. In this study, we tested whether the turquoise phase of colour change has a signaling role in inter- and intrasexual contexts. We predicted that females would prefer bright turquoise males over dull males, but found no evidence from several choice experiments to support this hypothesis. We also predicted that brighter males would win more fights than duller males. Whilst we did not find that brighter males won more fights in staged experiments, we found that the brightness of males who chose to enter fights was significantly correlated with their opponents’ brightness. Our results suggest that the brightness of males’ turquoise phase may provide competitors with important information about their rival’s fighting ability. 相似文献
27.
J. Scott Keogh Kate D. L. Umbers Eleanor Wilson Jessica Stapley Martin J. Whiting 《Behavioral ecology and sociobiology》2013,67(4):629-638
Sexual selection theory predicts different optima for multiple mating in males and females. We used mating experiments and genetic paternity testing to disentangle pre- and postcopulatory mechanisms of sexual selection and alternate reproductive tactics in the highly promiscuous lizard Eulamprus heatwolei. Both sexes mated multiply: 30–60 % of clutches were sired by two to four fathers, depending on the experiment. Larger males sired more offspring when we allowed male contest competition: 52 % of large males but only 14 % of small males sired at least one offspring. In the absence of male contest competition, females mated promiscuously and there was no large male advantage: 80 % of large males and 90 % of small males sired at least one offspring, and there was no evidence for last-male precedence. Multiple mating did not yield obvious direct or indirect benefits to females. E. heatwolei represents a complex system in which males attempt to improve their fertility success by limiting rivals from access to females and through adopting alternate reproductive tactics. Conversely, females exhibit no obvious precopulatory mate choice but may influence fitness through postcopulatory means by either promoting sperm competition or through cryptic female choice. Our results support the hypothesis that female multiple mating in nonavian reptiles is best explained by the combined effect of mate encounter frequency and high benefits to males but low costs to females. 相似文献
28.
Kate J. Darby 《Local Environment》2013,18(8):797-814
Residents in Paso del Norte (El Paso, Texas; Sunland Park, New Mexico; and Juárez, Mexico) have been concerned about heavy metal contamination in their communities since the 1970s, when high blood lead levels were found in children living in Smeltertown – a company town for the local metals smelter. After the smelter's closure in 1999, and throughout onsite and offsite cleanup efforts, residents have continued to express concerns about these contamination issues. Using a politics of scale framework and analysing ethnographic data and government, media and scientific documents, this paper identifies a set of major disjunctures between the scales of heavy metal contamination and the scales at which that contamination is regulated. These disjunctures exacerbate regional environmental injustice by complicating public participation, neglecting vulnerability and displacing hazards to new communities. Consequently, applying a politics of scale framework to this case study highlights regulatory and policy failures to address environmental justice. 相似文献
29.
Abstract Sustainability projects initiated by community groups can be significant in their contribution to the overall process of Local Agenda 21 planning and in their substantive contribution to sustainable communities. Community gardens differ from public gardens in that they are managed by community members rather than by local governments, although they may be located on council land. Community gardens vary in type from collections of individual plots to large‐scale collaborative projects for the benefit of the wider community. Their roles include the production of fresh organic food; the creation of community places; and the use and dissemination of community science and innovative technologies. This paper reviews the types and roles of community gardens, and provides a case study of a community garden in Western Australia. It analyses the lessons learned from this particular case and the potential contribution of community gardens to Local Agenda 21 planning and to physical, ecological, sociocultural and economic sustainability. 相似文献
30.
John A. Litvaitis Jeffrey L. Norment Kelly Boland Kate O’Brien Rachel Stevens Donald Keirstead Thomas Lee James D. Oehler Jeffery M. Taylor Susan Bickford Matthew D. Tarr 《Environmental management》2013,52(6):1313-1319
Limiting the spread of invasive plants has become a high priority among natural resource managers. Yet in some regions, invasive plants are providing important habitat components to native animals that are at risk of local or regional extirpation. In these situations, removing invasive plants may decrease short-term survival of the at-risk taxa. At the same time, there may be a reluctance to expand invaded habitats to benefit at-risk species because such actions may increase the distribution of invasive plants. Such a dilemma can result in “management paralysis,” where no action is taken either to reduce invasive plants or to expand habitats for at-risk species. A pragmatic solution to this dilemma may be to develop an approach that considers site-specific circumstances. We constructed a “discussion tree” as a means of initiating conversations among various stakeholders involved with managing habitats in the northeastern USA to benefit several at-risk taxa, including New England cottontails (Sylvilagus transitionalis). Major components of this approach include recognition that expanding some invaded habitats may be essential to prevent extirpation of at-risk species, and the effective control of invasive plants is dependent on knowledge of the status of invasives on managed lands and within the surrounding landscape. By acknowledging that management of invasive plants is a complex issue without a single solution, we may be successful in limiting their spread while still addressing critical habitat needs. 相似文献