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301.
Ian?H.?RowlandsEmail author 《Mitigation and Adaptation Strategies for Global Change》2011,16(7):749-773
This article analyses the debate associated with the ancillary impacts of climate change mitigation options in developing
countries, with a particular focus upon Africa’s 34 least developed countries. While these countries’ emissions of greenhouse
gases are relatively small (and they do not have emission limitation commitments in the current international regime), inattention
to the mitigation agenda would mean that developing countries both miss potential funding opportunities and fail to ‘climate-proof’
their development strategies. A focus, therefore, upon the short-term, local, developmental impacts that serve to change the
relative attractiveness of different mitigation options from the perspective of the developing country is in these countries’
current strategic interests. In this article, I examine three energy-related climate change mitigation options: improved cookstoves,
carbon-free electricity and improved energy efficiency in industry. Key ancillary impacts are better indoor air quality, better
outdoor air quality and job creation (respectively). Further work to strengthen the evidence base regarding these impacts
needs to be undertaken, potentially drawing upon broader work that has already been completed. Thus, in conclusion, a call
for cross-fertilisation of information between heretofore disparate research communities is made. Additionally, the development
of an integrated research agenda, forging linkages among cookstoves, indoor air quality and climate change mitigation research
communities in Africa’s least developed countries, is identified as a priority. 相似文献
302.
Ian C. Hewitt Alexander G. Fernald Zohrab A. Samani 《Journal of the American Water Resources Association》2018,54(4):962-973
Currently, there is no agreed upon method for estimating evapotranspiration (ET) across large regions such as the state of New Mexico. Remote sensing methods have potential for providing a solution, but require validation. A comparison between field‐scale ET measurements using a portable chamber ET measurement device and modeled ET using the remote sensing Regional Evapotranspiration Estimation Model (REEM) was performed where the model had not been previously evaluated. Data were collected during the growing season of 2015 in three irrigated agricultural valleys of northern New Mexico in agricultural and nonagricultural settings. No statistically significant difference was observed in agricultural datasets between means of measured (M = 3.7 mm/day, SE = 0.31 mm/day) and modeled (M = 4.0 mm/day, SE = 0.01 mm/day) daily ET; t(17) = ?1.50, p = 0.15, α = 0.05. As there was no statistical difference observed between agricultural datasets, results support the use of REEM in irrigated agricultural areas of northern New Mexico. A statistically significant difference was observed in nonagricultural datasets between means of measured (M = 1.7 mm/day, SE = 0.22 mm/day) and modeled (M = 0.0 mm/day, SE = 0.00 mm/day) daily ET; t(9) = 1.79, p = 5.7 × 10?6, α = 0.05. With additional calibrations and air temperature sensors placed outside of agricultural areas, REEM may be suitable for use in nonagricultural areas of northern New Mexico. 相似文献
303.
Emma R. Wilson Kelly L. Smalling Timothy J. Reilly Elmer Gray Laura Bond Lance Steele Prasanna Kandel Alison Chamberlin Justin Gause Nicole Reynolds Ian Robertson Stephen Novak Kevin Feris Merlin M. White 《Journal of the American Water Resources Association》2014,50(2):420-433
Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far‐reaching consequences within aquatic ecosystems. 相似文献
304.
Kristen M. Hart Autumn R. Sartain Zandy-Marie Hillis-Starr Brendalee Phillips Philippe A. Mayor Kimberly Roberson Roy A. Pemberton Jr. Jason B. Allen Ian Lundgren Susanna Musick 《Marine Biology》2013,160(10):2567-2580
Surveys of juvenile hawksbills around Buck Island Reef National Monument, US Virgin Islands from 1994 to 1999 revealed distributional patterns and resulted in a total of 75 individual hawksbill captures from all years; turtles ranged from 23.2 to 77.7 cm curved carapace length (CCL; mean 42.1 ± 12.3 cm SD). Juveniles concentrated where Zoanthid cover was highest. Length of time between recaptures, or presumed minimum site residency, ranged from 59 to 1,396 days (mean 620.8 ± 402.4 days SD). Growth rates for 23 juveniles ranged from 0.0 to 9.5 cm year?1 (mean 4.1 ± 2.4 cm year?1SD). Annual mean growth rates were non-monotonic, with the largest mean growth rate occurring in the 30–39 cm CCL size class. Gastric lavages indicated that Zoanthids were the primary food source for hawksbills. These results contribute to our understanding of juvenile hawksbill ecology and serve as a baseline for future studies or inventories of hawksbills in the Caribbean. 相似文献
305.
Alistair?ChealEmail author Michael?Emslie Ian?Miller Hugh?Sweatman 《Marine Biology》2012,159(5):1143-1154
The composition and functionality of ecologically important herbivorous fish assemblages were examined throughout much of
Australia’s Great Barrier Reef (GBR). Diversity and abundance of surgeonfishes (Acanthuridae), parrotfishes (Labridae) and
rabbitfishes (Siganidae) were strongly associated with position on the continental shelf, whilst effects of latitude were
weaker and inconsistent. Species distributions varied considerably amongst taxonomic groups; parrotfishes were mostly widespread
whilst distributions of surgeonfishes were often restricted. Most inshore environments supported depauperate herbivore assemblages
dominated by different taxa and functional groups compared with assemblages in offshore environments. There were also strong
cross-shelf transitions in the main taxa performing each functional role. Overall, this study show that the functional contributions
of herbivorous fish assemblages to important ecosystem processes and the contributing taxa vary considerably amongst different
GBR environments. Additionally, the two most numerically dominant herbivores actively select detritus, not algae, supporting
increasing evidence for the importance of detritus in coral reef ecology. 相似文献
306.
Ecologists trying to understand the value of habitat to animals must first describe the value of resources contained in the habitat to animals and, second, they must describe spatial variation in resource quality at a resolution relevant to individual animal foraging. We addressed these issues in a study of koalas (Phascolarctos cinereus) in a Eucalyptus woodland. We measured beneficial and deterrent chemical characteristics as well as the palatability of trees using a near-infrared spectroscopic model based on direct feeding experiments. Tree use by koalas was influenced by tree size and foliar quality but was also context-dependent: trees were more likely to be visited if they were surrounded by small, unpalatable trees or by large, palatable trees. Spatial autocorrelation analysis and several mapping approaches demonstrated that foliar quality is spatially structured in the woodland at a scale relevant to foraging decisions by koalas and that the spatial structure is an important component of habitat quality. 相似文献
307.
The aim of the present study was to assess the sonographic contour of the increased nuchal translucency (NT) and to correlate this with pregnancy outcome. Fifty sonographic images of fetuses with increased NT [>95th centile thickness of the normal range for crown–rump length (CRL) between 38 and 84 mm] were retrospectively assessed. In all the cases a complete pregnancy and even infancy follow-up (<36 months) was available. The NT appearances were subdivided into two forms: a ‘notched’ or ‘uniform’ appearance. The images were correlated with karyotype results [trisomy 21 (DS) vs euploid cases] and pregnancy outcome. Complicated outcomes were classified as being either DS fetuses, miscarriage or termination of pregnancy because of structural anomaly. Thus 30/35 (86%) of the euploid fetuses had a ‘uniformly’ increased NT, whereas 8/13 DS cases (62%) had a ‘notched’ appearance (Fisher's exact test, p=0.004). Additionally, 27/29 fetuses (93%) which had an uneventful pregnancy outcome had a ‘uniform’ increased NT, whereas 12/26 (57%) of the fetuses which had adverse pregnancy outcome had a ‘notched’ appearance of their NT (Fisher's exact test, p<0.001). Although it was not possible to correlate the sonographic data with post-evacuation microdissection findings, it is possible that a uniformly shaped, increased NT may be more representative of a developmental delay in a normal fetus. Conversely, a ‘notched’ nuchal surface may represent abnormal lymphatic or cardiovascular development more commonly seen in DS fetuses. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
308.
This paper addresses the compatibility of World Bank policies towards population growth, development and biodiversity in the Third World. The World Bank has been central to the design and implementation of the Global Environment Facility (GEF), the remit of which includes the conservation of global biodiversity. However, the Bank's influence over the facility has in itself created controversy which may undermine its effectiveness. More significantly, the Bank's commitment to the GEF is subverted by its policies in other social and economic sectors. The World Bank, together with the International Monetary Fund (IMF), directs the structural adjustment of Third World economies through economic deregulation and privatization. This approach exacerbates inequalities and further empowers large landowners who may then displace tenant farmers and claim exclusive rights to former common land. Thus, biodiversity loss occurs as large landowners reorientate the land use towards the production of export goods and dispossessed farmers invade marginal land. Population growth influences biodiversity loss through its contribution to agricultural intensification and the settlement of marginal land. The World Bank encourages this trend through its non-committal approach to population control, but more especially through structural adjustment's positive effect on fertility. 相似文献
309.
Relations of Habitat-Specific Algal Assemblages to Land Use and Water Chemistry in the Willamette Basin, Oregon 总被引:4,自引:0,他引:4
Benthic algal assemblages, water chemistry, and habitat were characterized at 25 stream sites in the Willamette Basin, Oregon, during low flow in 1994. Seventy-three algal samples yielded 420 taxa — mostly diatoms, blue-green algae, and green algae. Algal assemblages from depositional samples were strongly dominated by diatoms (76% mean relative abundance), whereas erosional samples were dominated by blue-green algae (68% mean relative abundance).Canonical correspondence analysis (CCA) of semiquantitative and qualitative (presence/absence) data sets identified four environmental variables (maximum specific conductance, % open canopy, pH, and drainage area) that were significant in describing patterns of algal taxa among sites. Based on CCA, four groups of sites were identified: streams in forested basins that supported oligotrophic taxa, such as Diatoma mesodon;small streams in agricultural and urban basins that contained a variety of eutrophic and nitrogen-heterotrophic algal taxa; larger rivers draining areas of mixed land use that supported planktonic, eutrophic, and nitrogen-heterotrophic algal taxa; and streams with severely degraded or absent riparian vegetation (> 75% open canopy) that were dominated by other planktonic, eutrophic, and nitrogen-heterotrophic algal taxa. Patterns in water chemistry were consistent with the algal autecological interpretations and clearly demonstrated relationships between land use, water quality, and algal distribution patterns. 相似文献
310.
Evaluating the vulnerability of surface waters to antibiotic contamination from varying wastewater treatment plant discharges 总被引:8,自引:0,他引:8
Effluents from three wastewater treatment plants with varying wastewater treatment technologies and design were analyzed for six antibiotics and caffeine on three sampling occasions. Sulfamethoxazole, trimethoprim, ciprofloxacin, tetracycline, and clindamycin were detected in the effluents at concentrations ranging from 0.090 to 6.0 microg/L. Caffeine was detected in all effluents at concentrations ranging from 0.19 to 9.9 microg/L. These findings indicate that several conventional wastewater management practices are not effective in the complete removal of antibiotics, and their discharges have a large potential to affect the aquatic environment. To evaluate the persistence of antibiotics coming from the wastewater discharges on the surrounding surface waters, samples were collected from the receiving streams at 10-, 20- and 100-m intervals. Ciprofloxacin, sulfamethoxazole, and clindamycin (0.043 to 0.076 microg/L) were found as far as 100 m from the discharge point, which indicates the persistence of these drugs in surface waters. 相似文献