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281.
Mikael Larsson Carl-Erik Grip Hans Ohlsson Staffan Rutqvist Jan-Olov Wikström Sten Ångström 《International Journal of Green Energy》2013,10(2):171-183
During the years 2001–2002, a comprehensive study regarding CO2 emissions related to the steel production for the integrated steel making production route, was carried out. The study was financed by SSAB and carried out by a research group with members from SSAB, MEFOS and LTU. The aim was to study the emissions from the existing system and how these could be influenced by process changes and by process modifications. The calculations were made using a global spreadsheet model for calculating the CO2 emissions, developed from an existing Energy and Process Integration model of the same system. The calculated cases included the existing BF/BOF route as well as integration of other processes, e.g., an electric arc furnace, DR processes, COREX and a new future smelting reduction process concept (Sidcomet). All new existing alternative ore based process technologies would increase the specific CO2 emission from the system. A technology transfer to scrap based metallurgy would significantly decrease the emission level, but is not feasible for SSAB, due to the future product mix and the structure of scrap availability. In a 5–20 year perspective, the existing steel making process route with the use of magnetite ore for pellet production has the lowest specific CO2 emission. In a long-term perspective, 20–50 years, alternative process routes, e.g., based on H2 and DRI, could be of interest. Studies on such changes are, however, big projects and should be carried out as joint European and/or international efforts. 相似文献
282.
Stored-product moths cause large economic damage in food processing industries and storage facilities. Control of indoor pests is currently dealt with locally, and control strategies seldom include different mills or cooperative industries in joint efforts to reduce infestations. In colder climates where conditions hinder flight dispersal of stored-product moths, we hypothesize that human transport between mills will facilitate dispersal. Albeit considered intuitive, this hypothesis has so far never been tested. Male moths from three mills (populations) in southern Sweden and Denmark were collected and by using amplified fragment length polymorphism (AFLP) pair-wise F(st) values were calculated. Cluster (population) origins of the genotypes were computed by using a model-based method, structure. The results suggest that known transportation of flour between two mills generate genetically more similar populations of the economically important stored-product moth, Ephestia kuehniella (Zell.) (Lepidoptera; Pyralidae), compared to the third mill, with another distribution area, but situated geographically in between the other mills. The structure model placed the sampled genotypes to belong to either two or five original populations, with a higher probability of two original populations. The third mill was consistently different from the other two mills independent of the models' calculated number of populations. Although the study was restricted to three mills and one transportation route, it highlights the possibility that transportation of food products promotes genetic mixing (i.e. dispersal) of insect pest populations. Including cooperating mills in control (or monitor) strategy schemes against stored-product pest insects would therefore be a more effective action, rather than to treat each mill separately. 相似文献
283.
Jacob D. Wiseman Michael R. Burchell Garry L. Grabow Deanna L. Osmond T.L. Messer 《Journal of the American Water Resources Association》2014,50(3):653-664
Riparian buffers have been used for many years as a best management practice to decrease the effects of nonpoint pollution from watersheds. The NC Conservation Reserve Enhancement Program (NC CREP) has established buffers to treat groundwater nitrate‐nitrogen (NO3?‐N) from agricultural sources in multiple river basins. A maturing 46 m wide riparian buffer enrolled in NC CREP was studied to determine its effectiveness in reducing groundwater NO3?‐N concentrations from a cattle pasture fertilized with poultry litter. Three monitoring blocks that included groundwater quality wells, water table wells, and soil redox probes, were established in the buffer. NO3?‐N concentrations decreased significantly across the buffer in all of the monitoring blocks with mean reductions of 76‐92%. Many biological processes, including denitrification and plant uptake, may have been responsible for the observed NO3?‐N reductions but could not be differentiated in this study. However, mean reductions in Cl? concentrations ranged from 48‐65% through the blocks, which indicated that dilution was an important factor in observed NO3?‐N reductions. These findings should be carefully considered for future buffer enrollments when assigning nitrogen removal credits. 相似文献
284.
Analytical methods for the determination of brominated flame retardants (BFRs), with a special emphasis on polybrominated diphenyl ethers (PBDEs) are reviewed. A number of procedures, which can be applied to the analysis of PBDEs and polybrominated biphenyls (PBBs), and in some cases for hexabromocyclododecane (HBCD), in environmental and human samples are described. Because several BFRs, such as tetrabromobisphenol-A (TBBP-A), BDE 209 and, to some extent, HBCD, may require a different approach, specific advice on their analysis is given separately when needed. Sample pretreatment, extraction, cleanup and fractionation, injection techniques, chromatographic separation, detection methods, quality control and method validation are discussed. For each topic, an overview is given of the current status of the field and recommendations for an appropriate analytical approach are presented. 相似文献
285.
Brose U Jonsson T Berlow EL Warren P Banasek-Richter C Bersier LF Blanchard JL Brey T Carpenter SR Blandenier MF Cushing L Dawah HA Dell T Edwards F Harper-Smith S Jacob U Ledger ME Martinez ND Memmott J Mintenbeck K Pinnegar JK Rall BC Rayner TS Reuman DC Ruess L Ulrich W Williams RJ Woodward G Cohen JE 《Ecology》2006,87(10):2411-2417
It has been suggested that differences in body size between consumer and resource species may have important implications for interaction strengths, population dynamics, and eventually food web structure, function, and evolution. Still, the general distribution of consumer-'resource body-size ratios in real ecosystems, and whether they vary systematically among habitats or broad taxonomic groups, is poorly understood. Using a unique global database on consumer and resource body sizes, we show that the mean body-size ratios of aquatic herbivorous and detritivorous consumers are several orders of magnitude larger than those of carnivorous predators. Carnivorous predator-prey body-size ratios vary across different habitats and predator and prey types (invertebrates, ectotherm, and endotherm vertebrates). Predator-prey body-size ratios are on average significantly higher (1) in freshwater habitats than in marine or terrestrial habitats, (2) for vertebrate than for invertebrate predators, and (3) for invertebrate than for ectotherm vertebrate prey. If recent studies that relate body-size ratios to interaction strengths are general, our results suggest that mean consumer-resource interaction strengths may vary systematically across different habitat categories and consumer types. 相似文献
286.
PAH-contaminated soil from a former gasworks site was treated with Fenton's reagent in a number of lab-scale slurry reactors. The degradation result obtained by traditional Fenton oxidation and Fenton oxidation preceded by ethanol treatment were compared. The ethanol pre-treatment enhanced the depletion of all PAHs in the soil by facilitating their desorption from the soil matrix. However, some PAHs, especially anthracene, benzo[a]pyrene and perylene, were more extensively depleted than other PAHs with fewer or equal numbers of fused rings, indicating that the hydroxyl radicals react faster with these PAHs than with other kinds. The ethanol present in the slurry also appeared to influence the relative reactivity of the PAHs. Furthermore, the enhanced oxidation that occurred in the ethanol pre-treated soil resulted in the accumulation of oxidation products. For example, 1-indanone, anthracene-9,10-dione, 1-methylanthracenedione, 2-methylanthracenedione, 1,8-naphthalic anhydride, benz[a]anthracene-7,12-dione and two compounds tentatively identified as hydroxy-9-fluorenones were found at higher concentrations after the treatment than before it. The accumulation was most evident for the quinones, and in many cases it could be attributed to extensive oxidation of their parent PAHs, although the total oxidation efficiency in this study was relatively poor. 相似文献
287.
Pablo V. Prieto Jacob J. Bukoski Felipe S. M. Barros Hawthorne L. Beyer Alvaro Iribarrem Pedro H. S. Brancalion Robin L. Chazdon David B. Lindenmayer Bernardo B. N. Strassburg Manuel R. Guariguata Renato Crouzeilles 《Conservation biology》2022,36(3):e13842
Natural forest regrowth is a cost-effective, nature-based solution for biodiversity recovery, yet different socioenvironmental factors can lead to variable outcomes. A critical knowledge gap in forest restoration planning is how to predict where natural forest regrowth is likely to lead to high levels of biodiversity recovery, which is an indicator of conservation value and the potential provisioning of diverse ecosystem services. We sought to predict and map landscape-scale recovery of species richness and total abundance of vertebrates, invertebrates, and plants in tropical and subtropical second-growth forests to inform spatial restoration planning. First, we conducted a global meta-analysis to quantify the extent to which recovery of species richness and total abundance in second-growth forests deviated from biodiversity values in reference old-growth forests in the same landscape. Second, we employed a machine-learning algorithm and a comprehensive set of socioenvironmental factors to spatially predict landscape-scale deviation and map it. Models explained on average 34% of observed variance in recovery (range 9–51%). Landscape-scale biodiversity recovery in second-growth forests was spatially predicted based on socioenvironmental landscape factors (human demography, land use and cover, anthropogenic and natural disturbance, ecosystem productivity, and topography and soil chemistry); was significantly higher for species richness than for total abundance for vertebrates (median range-adjusted predicted deviation 0.09 vs. 0.34) and invertebrates (0.2 vs. 0.35) but not for plants (which showed a similar recovery for both metrics [0.24 vs. 0.25]); and was positively correlated for total abundance of plant and vertebrate species (Pearson r = 0.45, p = 0.001). Our approach can help identify tropical and subtropical forest landscapes with high potential for biodiversity recovery through natural forest regrowth. 相似文献
288.
Elizabeth J. Golebie Miriam Aczel Jacob J. Bukoski Sophia Chau Natali Ramirez-Bullon Mimi Gong Noah Teller 《Conservation biology》2022,36(1):e13850
Management of mangrove ecosystems is complex, given that mangroves are both terrestrial and marine, often cross regional or national boundaries, and are valued by local stakeholders in different ways than they are valued on national and international scales. Thus, mangrove governance has had varying levels of success, analyzed through concepts such as principles of good governance and procedural justice in decision-making. Although there is substantial research on case studies of mangrove management, global comparisons of mangrove governance are lacking. This research aims to fill this gap by comparing relationships among qualities of governance across mangrove social-ecological systems worldwide. Through a systematic literature search and screening process, we identified 65 articles that discussed mangrove governance and conservation. Case studies in these articles, drawn from 39 countries, were categorized as top-down, bottom-up, or comanaged and thematically coded to assess the influence of eight principles of good governance in mangrove conservation success. Across all three governance systems, the principles of legitimacy, fairness, and integration were most important in determining conservation success or failure. These principles are closely related to the concept of procedural justice, highlighting the importance of stakeholder inclusion throughout all stages of mangrove management. Thus, we recommend clearly defined roles for all governance actors, transparent communication of policy development to stakeholders, fairness in both process and outcome, and careful consideration of sustainable access to conservation resources. 相似文献