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231.
Sari HämäläinenAuthor Vitae Annukka Näyhä Author VitaeHanna-Leena Pesonen Author Vitae 《Journal of Cleaner Production》2011,19(16):1884-1891
Bioenergy and biomass-based products offer the greatest new opportunities for diversifying business in the forest cluster. In particular, biorefineries, which can be integrated into the pulp and paper industry, seem to have immense future potential. This article aims to explore the biorefinery concept and related new products and business operations, as well as new business strategies and company models, which are part of the biorefinery value chain. These factors, which contribute to the establishment and success of forest biorefineries, were examined using internet survey responses and compared between Scandinavia, North America and South America. This article looks at the results of the survey - primarily from the Finnish perspective - to help identify competitive advantages upon which successful business operations in the Finnish forest cluster can be built.According to the survey, the outlooks for technical and raw material choices, as well as barriers to biorefinery diffusion, are very similar in all the studied areas. Biorefineries and related energy products are considered the way to sustainably guarantee the forest cluster’s success. An increase in the price of oil motivates the development of forest biorefineries and wood-based biofuels; however, it is obvious that there is a need to revaluate from a fresh perspective the utilisation of wood and the wood-refining chain in the forest cluster.The survey respondents consider wood-based biofuel and chemical production a serious business opportunity for the forest cluster. In Finland, there is a strong confidence in the production of biofuels. However, all the countries included in the study trust in their own national strengths and in their chance to be a leading actor in the forest biorefinery business worldwide. The forest biorefinery business seems to have market potential, and global competition can thus be expected. 相似文献
232.
Impact of fertilization on chestnut growth, N and P concentrations in runo
water on degraded slope land in South China 总被引:2,自引:0,他引:2
Growing fruit trees on the slopes of rolling hills in South China was causing serious environmental problems because of heavy application of chemical fertilizers and soil erosion. Suitable sources of fertilizers and proper rates of applications were of key importance to both crop yields and environmental protection. In this article, the impact of four fertilizers, i.e., inorganic compound fertilizer, organic compound fertilizer, pig manure compost, and peanut cake (peanut oil pressing residue), on chestnut (Castanea mollissima Blume) growth on a slope in South China, and on the total N and total P concentrations in runoff waters have been investigated during two years of study, with an orthogonal experimental design. Results show that the organic compound fertilizer and peanut cake promote the heights of young chestnut trees compared to the control. In addition, peanut cake increases single-fruit weights and organic compound fertilizer raises single-seed weights. All the fertilizers increased the concentrations of total N and total P in runoff waters, except for organic compound fertilizer, in the first year experiment. The observed mean concentrations of total N varied from 1.6 mg/L to 3.2 mg/L and P from 0.12 mg/L to 0.22 mg/L, which were increased with the amount of fertilizer applications, with no pattern of direct proportion. On the basis of these experiment results, organic compound fertilizer at 2 kg/tree and peanut cake at 1 kg/tree are recommended to maximize chestnut growth and minimize water pollution. 相似文献
233.
南黄海南部海域表层沉积物重金属来源解析及风险评价 总被引:3,自引:1,他引:2
基于2012年夏季对南黄海南部海域的调查资料,分析了表层沉积物中7种重金属元素的含量分布特征;采用多元统计分析,揭示了研究区表层沉积物重金属污染的主要来源及各元素之间的相关性;应用地质累积指数法和Hakanson潜在生态风险指数法对重金属元素进行了污染及风险分析.结果表明:Cd、Pb的含量均符合国标规定的一类沉积物标准,Zn、Cu、Cr在绝大部分站位也都低于国标规定的一类沉积物的最高标准,仅在个别站位处达到二类或三类沉积物标准;除Cr、Cd、Mn外,其余各重金属与Al2O3、平均粒径之间有显著的相关性,表明它们均以自然来源为主,并受到沉积物粒度的控制,遵循"元素的粒度控制律";Cr、Cd、Mn与Al2O3的相关系数较小,表明其可能受到人为污染源的影响.通过主成分分析和聚类分析可将7种重金属元素辨识为2个主成分,PC1(Zn、Cu、Pb、Fe、Mn)为自然源因子,PC2(Cr、Cd)为工农业源因子;其中,Cr、Cd在PC1和PC2上均具有一定的正载荷,受自然地质背景和人类活动的共同控制.地质累积指数法评价结果表明,Zn、Cu、Cd、Pb整体均处于清洁级别,而Cr则处于轻微污染水平,污染程度排序依次为CrPbCdZnCu;潜在生态风险评价结果表明,各元素潜在生态危害等级排序依次为CdPbCuCrZn,Cr、Zn、Cu和Pb均为低生态危害等级,Cd以低中等生态危害等级为主,局部出现较重生态危害等级,综合潜在生态风险评价为低度. 相似文献
234.
苏南经济快速发展区土壤有效态镉含量影响因素及分布特征 总被引:11,自引:0,他引:11
研究了农田土壤有效态镉含量的影响因素及分布特征。结果表明:① 土壤有效态Cd含量总体较高,平均值为0.092 mg/kg,最大值高达0.354 mg/kg,且土壤Cd的平均活化率高达53%,Cd是该区主要的重金属污染物之一;②土壤表层有效态Cd含量与全Cd含量呈极显著正相关,回归分析表明该区农田土壤有效态Cd含量主要受全Cd含量的影响;③在不同经济功能区,有效态Cd和土壤Cd的活化率均以化工区为高,在不同地貌区,二者均以中部平原区最高,中部平原区Cd的活化率显著高于北部洼区;④在土壤剖面上,土壤有效态Cd含量和土壤Cd的活化率均以表层为高,表明土壤Cd的环境风险主要集中在表层20 cm。 相似文献
235.
Abstract: At present most of the large rivers of South America are impounded. Management plans historically have relied on the construction of fish passages, specifically ladders, to mitigate the impact of these waterway blockages on fisheries and biodiversity. Nevertheless, the design of these facilities is not ecologically sound and they are not monitored continually. Consequently, the real role of South American fish passages in fisheries and biodiversity management is unclear and the results of some studies suggest that ladders are problematic in fish conservation. We examined the characteristics and negative aspects of fish passages within a larger context and considered the notion that these facilities are ecological traps in some Brazilian impoundments. Four conditions are required to characterize a fish passage as an ecological trap: (1) attractive forces leading fish to ascend the passage; (2) unidirectional migratory movements (upstream); (3) the environment above the passage has poor conditions for fish recruitment (e.g., the absence of spawning grounds and nursery areas); and (4) the environment below the passage has a proper structure for recruitment. When these conditions exist individuals move to poor-quality habitats, fitness is reduced, and populations are threatened. To exemplify this situation we analyzed two case studies in the upper Paraná River basin, Brazil, in which the four conditions were met and migratory fish populations were declining. If passages work as ecological traps, regional fisheries will be in danger of collapse and conservation policies toward biodiversity will become more difficult and ineffective. The situation demands the closing of the passage in conjunction with alternative management actions to preserve system functionality, especially the conservation of critical habitats downstream and the restoration of damaged habitats in the region. 相似文献
236.
天津市南运河河道整治景观设计 总被引:1,自引:0,他引:1
依据天津南运河河道沿岸的场地特征,确定了南运河河道整治景观设计的目标和原则,重点探析南运河线形文化景观遗存和滨河环境空间利用的实现形式,并认为南运河河道整治景观设计应建立沿岸连续的步行系统。依据道路与河面的高度差,建立6个不同的景观节点,采取生态护堤措施,保护和完善生态廊道,建立统一完善的历史文化传承体系。 相似文献
237.
Huanyu Chang Yong Zhao Qingming Wang Jianhua Wang Haihong Li Jiaqi Zhai Jingyan Han Shan Jiang 《Journal of the American Water Resources Association》2020,56(2):230-246
Since its implementation in 2015, the Middle Route of the South‐to‐North Water Diversion Project (MR‐SNWDP) has transferred an average of 45 billion cubic meters of surface water per year from the Yangtze River in southern China to the Yellow River and Hai River Basin in northern China, but how that supply is able to cope with droughts under different scenarios has not been explored. In this study, using the water demand for 2020 as the guaranteed water target, a Water Evaluation and Planning system was used to simulate available water supplies in Beijing under different drought scenarios. In the case of a single‐year drought, without the MR‐SNWDP, Beijing’s water shortage ratio was 16.7%; with the MR‐SNWDP, this ratio reduced to 7.3%. In the case of a multi‐year drought, without the MR‐SNWDP, Beijing’s water shortage ratio was 25.3%; with the MR‐SNWDP, this ratio reduced to 7.4% and domestic water supply was improved. Our research suggests that to prepare for multi‐year drought in the Beijing area, the SNWDP supports increased supplies to the region that would mitigate drought effects. This study is, however, mostly focused on water supply provision to Beijing and does not comprehensively evaluate other potential impacts. Multiple additional avenues could be pursued that include replenishing groundwater, increasing reservoir storage, and water conservation methods. Further research is needed to explore the relative costs and benefits of these approaches. 相似文献
238.
海螺沟背景站地处人烟稀少、远离工业带区域,颗粒物浓度水平与美国背景区域相当,通常情况下各项污染物浓度呈周期性缓慢变化,但通过实时自动监测发现,也有部分时段出现污染物浓度急剧升高的现象,对这种情况进行统计分析,2015年共有43 d因远距离传输导致背景站浓度急剧升高现象,其间PM_(2.5)平均质量浓度为19.4μg/m~3,比其年均质量浓度(8.3μg/m~3)高1倍多。通过对2015年背景站监测数据与年气象分析资料的联合分析,结合HSPLIT 4.8轨迹模式对污染物来源进行溯源,在海螺沟国家大气背景区域的200、3 700 m 2个高度都存在南亚次大陆向中国境内输送的气流路径。后向轨迹200 m高度聚类分析结果:海螺沟背景站PM_(2.5)监测值超"正常"浓度范围时段有84%的大气污染气团主要来自南亚次大陆方向,同时,常规6项其他监测项目的浓度水平也存在协同上升效应。 相似文献
239.
Dechlorane Plus (DP) is a chemical of emerging concern due to the restrictions on brominated flame retardant formulations. However, very little information is known about the occurrence of DP in indoor and outdoor air and its associated health risk to the exposed human population. In this study, we examined the concentrations and isomer profiles of DP in archived air samples collected from 14 homes, 6 offices, and 10 public microenvironments in Guangzhou, China in 2004–2005. The average (median) value of atmospheric ΣDP (sum of anti-DP and syn-DP) concentration in the three indoor air was 5.73 ± 5.33 (3.62) for offices, 8.08 ± 5.17 (6.87) for homes, and 57.27 ± 83.08 (32.58) pg/m3 for public microenvironments, respectively. ΣDP concentration was significantly higher in the public microenvironments than those in homes and offices. The arithmetic mean and median concentrations of ΣDP in outdoor air were 36.00 and 28.76 pg/m3, respectively. Spatially and temporally consistent indoor and outdoor samples comparison suggested that outdoor air might be a relevant source of DP for indoor air. Average anti-DP fractional abundance (fanti = 0.65 ± 0.04) in all outdoor samples was similar to those reported in other studies and indistinguishable from that of the commercial mixture (fanti = 0.65). In contrast, a relatively large variation of fanti values was found in the indoor samples, suggesting a complex degradation process of DP existing in these microenvironments. The calculated average daily doses of ΣDP were in the range of 0.38–2.21 ng/day for people intake through air inhalation, which was in the same order of magnitude compared with other exposure pathways for the general publics. 相似文献
240.
Ammophila arenaria (marram or European beach grass) for dune stabilization in South Africa in the past and present, its present distribution
in South Africa, and the perceptions of coastal management agencies and the public about its further use. The planting of
A. arenaria became the most important means of dune stabilization, by human intervention, along the South African Cape coast in this
century. Its modern distribution from the semiarid west coast to the subtropical shores of the Eastern Cape extends through
various climatic zones. Although historical data are missing for some areas, there is no indication of its unaided spread.
A. arenaria occurs at most sites because of its prior planting. The South African climate appears to affect its vigor. However, concern
about the use of the alien grass has been raised since it has proved to be a highly invasive species in other parts of the
world, particularly along the North American west coast and in Tasmania. While the CSIR (Council of Scientific and Industrial
Research) promotes its use, CNC (Cape Nature Conservation) follows a policy that restricts the use of any alien plant, including
A. arenaria, and requests further research on its invasive properties. Although a questionnaire survey shows that stabilization sites
featuring large areas of A. arenaria are accepted by the South African public, current coastal management practices need to be analyzed critically. A thorough
investigation of the potential invasiveness of A. arenaria on South African coastal dunes will be essential and shed new light on the American A. arenaria problem. 相似文献