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81.
Roitberg BD Gillespie DR Quiring DM Alma CR Jenner WH Perry J Peterson JH Salomon M VanLaerhoven S 《Die Naturwissenschaften》2005,92(9):431-434
Evolutionary and ecological transitions from carnivorous to omnivorous feeding may be constrained by the ability of the animal
to cope with disparate types of foods, even if preadaptations for such behaviour exist. The omnivorous true bug, Dicyphus hesperus (Hemiptera: Miridae) requires both animals (small, soft-bodied insects) and plants in its diet and obtains the majority of
its dietary and metabolic water from plant feeding. Serrations on the lateral margins of the mandibular stylets wear with
age, and this wear is exacerbated when the insects feed on plants compared to those provided free water and no plants. D. hesperus that feed on plants attack fewer prey but consumed similar amounts of prey tissue compared to individuals that were provided
free water. Although others have shown mandible wear for plant-chewing animals we show for the first time that plant feeding
can impose similar wear on plant-piercing animals as well. 相似文献
82.
William J. de Groot Robert D. Field Michael A. Brady Orbita Roswintiarti Maznorizan Mohamad 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):165-180
Forest and land fires in Southeast Asia have many social, economic, and environmental impacts. Tropical peatland fires affect
global carbon dynamics, and haze from peat fires has serious negative impacts on the regional economy and human health. To
mitigate these fire-related problems, forest and land management agencies require an early warning system to assist them in
implementing fire prevention and management plans before fire problems begin. Fire Danger Rating Systems (FDRS) were developed
for Indonesia and Malaysia to provide early warning of the potential for serious fire and haze events. In particular, they
identify time periods when fires can readily start and spread to become uncontrolled fires and time periods when smoke from
smouldering fires will cause an unacceptably high level of haze. The FDRS were developed by adapting components of the Canadian
Forest Fire Danger Rating System, including the Canadian Forest Fire Weather Index (FWI) System and the Canadian Forest Fire
Behavior Prediction (FBP) System, to local vegetation, climate, and fire regime conditions. A smoke potential indicator was
developed using the Drought Code (DC) of the FWI System. Historical air quality analysis showed that the occurrence of severe
haze events increased substantially when DC was above 400. An ignition potential indicator was developed using the Fine Fuel
Moisture Code (FFMC) of the FWI System. Historical hot spot analysis, grass moisture, and grass ignition studies showed that
fire occurrence and the ability for grass fires to start and spread dramatically increased when FFMC > 82. The Initial Spread
Index (ISI) of the FWI System was used to develop a difficulty of control indicator for grassland fires, a fuel type that
can exhibit high rates of spread and fire intensity. This ISI-based indicator was developed using the grass fuel model of
the FBP System, along with a standard grass fuel load and curing level estimated from previous Indonesian studies. Very high
fire intensity is expected in grasslands when ISI ≥ 6. To provide early warning, the FDRS identifies classes of increasing
fire danger as the FFMC, DC, and ISI approach these key threshold values. The Indonesian FDRS is now operated nationally at
the Indonesian Meteorological and Geophysical Agency. The Malaysian Meteorological Service operates the Malaysian FDRS and
displays regional outputs for the Association of Southeast Asian Nations. The FDRS are being used by forestry, agriculture,
environment, and fire and rescue agencies to develop and implement fire prevention, detection, and suppression plans. 相似文献
83.
84.
Colleen Jacob Tim McDaniels Scott Hinch 《Mitigation and Adaptation Strategies for Global Change》2010,15(8):859-876
This paper provides a culturally-informed understanding of the impacts of climate change on a highly important subsistence
activity that has been practiced by First Nations of central British Columbia for thousands of years. The paper begins with
a review of the science regarding sockeye salmon and climate change. It discusses harvest patterns, and how the timing of
runs has changed. A survey was conducted by the first author regarding St’át’imc traditional fishing at a historic site on
the Fraser River, in 2005. The results show that the impacts of climate change are apparent to those conducting traditional
fishing practices, in terms of changed timing and abundance of salmon runs. These perceptions fit closely with the information
available from scientists and management agencies. These changes are highly problematic for the St’át’imc, in that the preservation
method (drying) is tied to seasonal weather patterns. The whole cultural setting, and the relevance of salmon for subsistence
would be highly altered by climate change that leads to changes in the timing and abundance of sockeye salmon. The paper discusses
mitigation and adaptation alternatives, but also indicates the scope of these seem limited, given the resource systems and
the context of these activities. 相似文献
85.
Nina Bhola Helen Klimmek Naomi Kingston Neil D. Burgess Arnout van Soesbergen Colleen Corrigan Jerry Harrison Marcel T. J. Kok 《Conservation biology》2021,35(1):168-178
During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of “living in harmony with nature.” We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision. 相似文献
86.
This paper focuses on efforts to produce an operational definition of the concept of ‘sustainable development’ as articulated by the 1992 United Nations Conference on Environment and Development (UNCED). ‘Sustainability’ has become an increasingly significant environmental issue; the problems in articulating a workable concept will differ among nations and international organizations attempting to define the term. Additionally, the term encompasses the varied fields of ecology, philosophy, and economics; every discipline imparts its own bias. Various definitions are provided and the significance and difficulty of developing an operational definition of Sustainable development is discussed. For example, sustainable development has become a ‘needs'-oriented term, an entitlement that priority should be given to the needs of the world's poor. Some argue that living standards which go beyond the basic minimum are sustainable only if consumption standards everywhere have regard for long-term sustainability. Scientifically, sustainability involves replicability and regeneration through an unforeseeable future. When prices reflect social cost and there are no externalities, optimal choices will be made between present and future consumption. Much of the debate involving sustainability involves deep-rooted fears or phobias, e.g. resource depletion, ‘energy crises’ and ‘timber crises’. 相似文献
87.
James L. Krumhansl Patrick V. Brady Howard L. Anderson 《Journal of contaminant hydrology》2001,47(2-4)
137Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137Cs from soils and groundwaters is exceedingly difficult. Because the half-life of 137Cs is only 30.2 years, remediation might be more effective (and less costly) if 137Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135Cs (half-life 2.3×106 years) in addition to 137Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention, Cs desorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO3 and LiCl washes. Washed clays were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F-Ill were similar; 0.017% to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12% to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were Cs-doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake. However, the residual loading was greatest on K-Mbt (0.33 wt.% Cs). Thus, this clay would be the optimal material for constructing artifical reactive barriers. 相似文献
88.
Phylogeny, niches, and relative abundance in natural communities 总被引:3,自引:0,他引:3
Community structure refers to the number of species in a community and the pattern of distribution of individuals among those species. We use a novel way of representing community structure to show that abundance within closely related pairs of co-occurring tree species in a highly diverse Mexican forest is more equitable than is abundance within more distantly related pairs. This observation is at odds with the fundamental assumption of neutral models of community structure, i.e., that species are interchangeable. The observed patterns suggest niche apportionment, in which interaction is focused pairwise between congeners but falls away from the phylogenetic structure above the genus level. Thus niche processes may significantly affect community structure through regulating relative abundance in a substantial proportion of species, which in turn potentially enhances community stability. One such mechanism of stable coexistence has already been shown to be active in this forest. 相似文献
89.
This paper systematically reviews the literature on how to reduce nutrient emissions to the Baltic Sea cost-effectively and considerations for allocating these costs fairly among countries. The literature shows conclusively that the reduction targets of the Baltic Sea Action Plan (BSAP) could be achieved at considerably lower cost, if countries would cooperate to implement the least costly abatement plan. Focusing on phosphorus abatement could be prudent as the often recommended measures—wastewater treatment and wetlands—abate nitrogen too. An implication of our review is that the potential for restoring the Baltic Sea to good health is undermined by an abatement strategy that is more costly than necessary and likely to be perceived as unfair by several countries. Neither the BSAP nor the cost-effective solution meet the surveyed criteria for fairness, implying a need for side-payments.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01580-4. 相似文献
90.
Environmental Management - Grizzly bears (Ursus arctos) appear to be attracted to natural and anthropogenic forage along railways, which may increase collision vulnerability, but also potentially... 相似文献