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51.
Colleen J. Howell Kurt A. Schwabe Azizan Haji Abu Samah 《Environment, Development and Sustainability》2010,12(1):1-18
Non-timber forest products (NTFP) represent key sources of cash and subsistence income for millions of rural and indigenous
peoples living in tropical developing countries throughout the world. The current study investigates the use and significance
of NTFP within a sample of Peninsular Malaysia’s Orang Asli (indigenous people). Data collected via household surveys across
three sampling phases reveals that more than 75% of the population is actively engaged in NTFP collection. Household responses
indicate diversity in both the types and uses of products collected. NTFP collection participation, frequency of collection,
and collection reliance are found to be significantly negatively related to village proximity to the market, as well as to
income level relative to the Malaysian poverty line. When collection variables are examined by different product categories,
relationships with market access and income group are variable. Implications for different approaches to forest conservation
and rural development are discussed. 相似文献
52.
This paper seeks to contribute to understanding of the factors associated with an effective emergent emergency response organisation and to provide new insights into this understudied area. It examines, through an analysis of a range of textual resources, the emergence and re‐emergence of the Student Volunteer Army (SVA) during the devastating earthquakes in Canterbury, New Zealand, in 2010–11. This evaluation is conducted in relation to the four key features of an effective emergency response organisation: adaptability; direction; leadership; and communication. In addition, the paper aims to further understanding of ‘emergency entrepreneurship’ and thus of the values and strategies that underpin social entrepreneur organisations in times of normalcy. The paper concludes that the unique position of the SVA as a ‘repeat emergent’ emergency response organisation enabled it to innovate continually and to improve repeatedly its systems, relationships, and image, such that it exhibited features common to emergent and established emergency response organisations. 相似文献
53.
54.
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
55.
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
56.
Seymour Colleen L. Gillson Lindsey Child Matthew F. Tolley Krystal A. Curie Jock C. da Silva Jessica M. Alexander Graham J. Anderson Pippin Downs Colleen T. Egoh Benis N. Ehlers Smith David A. Ehlers Smith Yvette C. Esler Karen J. O’Farrell Patrick J. Skowno Andrew L. Suleman Essa Veldtman Ruan 《Ambio》2020,49(6):1211-1221
Ambio - A horizon scan was conducted to identify emerging and intensifying issues for biodiversity conservation in South Africa over the next 5–10 years. South African biodiversity... 相似文献
57.
A series of laboratory experiments was conducted with a multiple-component immiscible liquid, collected from the Picillo Farm Superfund Site in Rhode Island, to examine liquid-vapor mass-transfer behavior. The immiscible liquid, which comprises solvents, oils, pesticides, PCBs, paint sludges, explosives, and other compounds, was characterized using gas chromatography and gas chromatography/mass spectrometry to determine mole fractions of selected constituents. Batch experiments were conducted to evaluate equilibrium phase-partitioning behavior. Two sets of air-stripping column studies were conducted to examine the mass-transfer dynamics of five selected target compounds present in the immiscible-liquid mixture. One set of column experiments was designed to represent a system with free-phase immiscible liquid present; the other was designed to represent a system with a residual phase of immiscible liquid. Initial elution behavior of all target components generally appeared to be ideal for both systems, as the initial vapor-phase concentrations were similar to vapor-phase concentrations measured for the batch experiment and those estimated using Raoult's law (incorporating the immiscible-liquid composition data). Later-stage removal of 1,2-dichlorobenzene appeared to be rate limited for the columns containing free-phase immiscible liquid and no porous medium. Conversely, evaporative mass transfer appeared to be ideal throughout the experiment conducted with immiscible liquid distributed relatively uniformly as a residual phase within a sandy porous medium. 相似文献
58.
Nitrogen uptake, distribution, turnover, and efficiency of use in a CO2-enriched sweetgum forest 总被引:2,自引:0,他引:2
The Progressive Nitrogen Limitation (PNL) hypothesis suggests that ecosystems in a CO2-enriched atmosphere will sequester C and N in long-lived biomass and soil organic pools, thereby limiting available N and constraining the continued response of net primary productivity to elevated [CO2]. Here, we present a six-year record of N dynamics of a sweetgum (Liquidambar styraciflua) stand exposed to elevated [CO2] in the free-air CO2 enrichment (FACE) experiment at Oak Ridge, Tennessee, USA. We also evaluate the concept of PNL for this ecosystem from the perspective of N uptake, content, distribution, and turnover, and N-use efficiency. Leaf N content was 11% lower on a leaf mass basis (NM) and 7% lower on a leaf area basis (NA) in CO2-enriched trees. However, there was no effect of [CO2] on total canopy N content. Resorption of N during senescence was not altered by [CO2], so NM of litter, but not total N content, was reduced. The NM of fine roots was not affected, but the total amount of N required for fine-root production increased significantly, reflecting the large stimulation of fine-root production in this stand. Hence, total N requirement of the trees was higher in elevated [CO2], and the increased requirement was met through an increase in N uptake rather than increased retranslocation of stored reserves. Increased N uptake was correlated with increased net primary productivity (NPP). N-use efficiency, however, did not change with CO2 enrichment because increased N productivity was offset by lower mean residence time of N in the trees. None of the measured responses of plant N dynamics in this ecosystem indicated the occurrence of PNL, and the stimulation of NPP by elevated [CO2] was sustained for the first six years of the experiment. Although there are some indications of developing changes in the N economy, the N supply in the soil at this site may be sufficient to meet an increasing demand for available N, especially as the roots of CO2-enriched trees explore deeper in the soil profile. 相似文献
59.
60.
Organic compounds derived from coal-tar wastes in a contaminated aquifer in St. Louis Park, Minnesota, were identified, and their partition coefficients between the tar phase and aqueous phase were determined and compared with the corresponding n-octanol/water partition coefficients. Coal tar contains numerous polycyclic aromatic compounds, many of which are suspected carcinogens or mutagens. Groundwater contamination by these toxic compounds may pose an environmental health hazard in nearby public water-supply wells. Fluid samples from this aquifer developed two phases upon settling: an upper aqueous phase, and a lower oily-tar phase. After separating the phases, polycyclic aromatic compounds in each phase were isolated using complexation with N-methyl-2-pyrrolidone and identified by fused-silica capillary gas chromatography/mass spectrometry. Thirty-one of the polycyclic aromatic compounds were chosen for further study from four different classes: 12 polycyclic aromatic hydrocarbons, 10 nitrogen heterocycles, 5 sulfur heterocycles, and 4 oxygen heterocycles. Within each compound class, the tar/water partition coefficients of these compounds were reasonably comparable with the respective n-octanol/water partition coefficient. 相似文献