Can Export-Oriented Aquaculture in Developing Countries be Sustainable and Promote Sustainable Development? The Shrimp Case

Industrial shrimp farming has been promoted by international development and financial institutions in coastal indebted poor countries as a way to obtain foreign exchange earnings, reimburse external debt, and promote development. The promotion of the shrimp industry is a clear example of a more general trend of support of export-oriented primary products, consisting in monocultures of commodities, as opposed to the promotion of more diverse, traditional production directed to feed the local population. In general, it is assumed that export-oriented aquaculture and agriculture, in a framework of liberalization policies, facilitates economic growth and this is associated with poverty reduction and the improvement of food security. However, it has been shown that the promotion of export-oriented production, mostly in the hands of big corporations, can have detrimental consequences for the livelihoods of local populations and the environment. As a result, international institutions, NGOs, and the industry aim to minimize these impacts by promoting sustainable export-oriented production. But some impacts may remain, since the main issue is the primary focus on international deregulated markets and the search for cheap primary products. To illustrate the relationships between the mainstream concept of development, the environmental and social impact of industrial farming systems, and the promotion of export-oriented production in developing countries, this article analyzes the case of the shrimp aquaculture industry.     

硫酸锰渣污染土壤中重金属的形态分布及生物活性

测定了硫酸锰渣污染土壤中Cu,Zn,Cd,Pb,Mn的总量和各形态含量.结果表明重金属总量远超过环境背景值和土壤环境二级标准.重金属各形态分布特征:Cu,有机态>残渣态>铁锰氧化态>碳酸盐态>可交换态;Zn,残渣态>铁锰氧化态>有机态>碳酸盐态>可交换态;Cd,铁锰氧化态>可交换态>碳酸盐态>残渣态>有机态;Pb,铁锰氧化态>残渣态>有机态>碳酸盐态>可交换态;Mn,铁锰氧化态>残渣态>可交换态>有机态>碳酸盐态.重金属的生物可利用性系数和迁移系数均为Cd>Mn>Pb>Cu>Zn.     

Effects of low concentrations of the phenylurea herbicide diuron on biofilm algae and bacteria

A system of recirculating channels was used in this study to examine the long-term effects (29 d) of environmentally realistic concentrations of the herbicide diuron (from 0.07 to 7 μg L⁻¹) on biofilm communities. The autotrophic activity of biofilms was affected by this herbicide, as reflected by a marked decrease in the photosynthetic efficiency. Diuron exposure also increased chlorophyll-a content and reduced the biovolume of diatom taxa at low concentrations. The effects on bacteria were also remarkable. Bacterial abundance was reduced after a week of exposure to the herbicide at a range of concentrations. Effects were on the number of live bacteria and on the increase in the leucine-aminopeptidase activity. It is suggested that inputs of herbicides to the river ecosystem at low concentrations may cause a chain of effects in the biofilm, which include inhibitory effects on algae but also indirect effects on the relationships between biofilm components.     

T型氧化沟提高脱氮效率的技术改造

采用延长边沟闷曝时间的方法对BOD降解模式T型氧化沟进行提高脱氮效率的改造。结果表明,边沟闷曝时间由0.5 h增至1 h,系统反硝化和硝化运行时间比t_DN/t_N由0.56调整至0.50时,提高了系统的NH₃-N的硝化效率,强化了脱氮能力。工艺改造后出水NH3-N浓度由改造前15.5 mg/L显著降低至10.4 mg/L,达到了广东省地方标准（DB 44/26-2001）第一时段的二级排放要求;系统脱氮效率由改造前52.1%显著提高到68.3％,有效地解决了污水厂出水NH₃-N浓度过高的问题;具有投资少、效果明显的特点,有一定的推广价值。     

“日全食经济”：掀起观天风暴

2009年7月22日上午8时左右,在我国长江中下游地区就将迎来近2000年来持续时间最长的一次日全食奇观。随着这一“美妙而壮丽”时刻的临近,长江流域30多个中城市掀起了有史以来最大的“观天”风暴,由此也带动了与日全食有关的旅游、食饮、住宿、交通、数码产品等行业和消费经济的快速升温。中国是最佳观测地也引起了世界关注。     

Concentrations of PCDD/Fs,PCBs and PBDEs in breast milk of women from Catalonia,Spain: A follow-up study

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in breast milk from women living in the vicinity of a new hazardous waste incinerator (HWI) in Catalonia, Spain. The results were compared with the levels obtained in two previous surveys carried out in 1998 (baseline study) and 2002. The current concentrations of PCDD/Fs in breast milk ranged from 45 to 143 pg/g fat (2.8 to 11.2 pg WHO-TEQ/g fat), while total PCBs ranged from 114 to 617 pg/g fat (2.8 to 17.6 pg WHO-TEQ/g fat). PBDE concentrations (sum 15 congeners) ranged from 0.57 ng/g fat to 5.9 ng/g fat, with a mean value of 2.5 ng/g fat. A general decrease of the concentrations for PCDD/Fs and both planar and total PCBs was observed. Regarding to PBDE concentrations in breast milk, similar levels between the 2002 and the present study were noted. The levels of PCDD/Fs and PCBs in milk of women living in urban areas were higher than those corresponding to the industrial zones (38% and 40%, respectively). However, the current PBDE levels were slightly lower (13%) in the urban than in the industrial zone. For PCDD/Fs and PCBs, the current decreases are in accordance with the reduction in the dietary intake of these pollutants found in recent studies carried out in the same area of study.     

Development of a Methodology for Strategic Environmental Assessment: Application to the Assessment of Golf Course Installation Policy in Taiwan

Some countries, including Taiwan, have adopted strategic environmental assessment (SEA) to assess and modify proposed policies, plans, and programs (PPPs) in the planning phase for pursuing sustainable development. However, there were only some sketchy steps focusing on policy assessment in the system of Taiwan. This study aims to develop a methodology for SEA in Taiwan to enhance the effectiveness associated with PPPs. The proposed methodology comprises an SEA procedure involving PPP management and assessment in various phases, a sustainable assessment framework, and an SEA management system. The SEA procedure is devised based on the theoretical considerations by systems thinking and the regulative requirements in Taiwan. The positive and negative impacts on ecology, society, and economy are simultaneously considered in the planning (including policy generation and evaluation), implementation, and control phases of the procedure. This study used the analytic hierarchy process, Delphi technique, and systems analysis to develop a sustainable assessment framework. An SEA management system was built based on geographic information system software to process spatial, attribute, and satellite image data during the assessment procedure. The proposed methodology was applied in the SEA of golf course installation policy in 2001 as a case study, which was the first SEA in Taiwan. Most of the 82 existing golf courses in 2001 were installed on slope lands and caused a serious ecological impact. Assessment results indicated that 15 future golf courses installed on marginal lands (including buffer zones, remedied lands, and wastelands) were acceptable because the comprehensive environmental (ecological, social, and economic) assessment value was better based on environmental characteristics and management regulations of Taiwan. The SEA procedure in the planning phase for this policy was completed but the implementation phase of this policy was not begun because the related legislation procedure could not be arranged due to a few senators’ resistance. A self-review of the control phase was carried out in 2006 using this methodology. Installation permits for 12 courses on slope lands were terminated after 2001 and then 27 future courses could be installed on marginal lands. The assessment value of this policy using the data on ecological, social, and economic conditions from 2006 was higher than that using the data from 2001. The analytical results illustrate that the proposed methodology can be used to effectively and efficiently assist the related authorities for SEA.     

Study on recycled asphalt concrete for use in surface course in airport pavement

This research investigated the possibility of using recycled asphalt concrete as surface course in airport pavement. The basic properties of recycled asphalt binder after short- and long-term aging were firstly tested and compared with those of the virgin asphalt. Then, a series of laboratory tests were performed to evaluate the performance of recycled asphalt concrete (containing 40% and 70% RAP), in which the HMA mixture without RAP was used as a control. Furthermore, an experimental pavement consisting of three sections (corresponding to 0%, 40% and 70% RAP content) was constructed to verify the laboratory test results. These results indicated that the recycled asphalt could achieve the similar properties against long-term aging as virgin asphalt. Recycled asphalt concrete containing 40% RAP could be used as surface course in airport pavement as it exhibited similar performance as control mixture both from the laboratory and experimental pavement test results. On the contrary, recycled asphalt concrete containing 70% RAP was not recommended as its fatigue property was much poorer compared with that of virgin asphalt mixture.     

The Adsorption of Formaldehyde on Suspended Particles investigated on model systems

Our laboratory investigation aimed at assessing to what extent suspended particles could adsorb formaldehyde, allowing it, when inhaled, to penetrate deeper into the lung. We used two types of pure soot, N-220 and N-660 (the former being a highly active oil furnace soot with smaller particles and a larger surface area than the latter), because of their chemical inactivity and the adsorptive properties. The results obtained in experimental conditions showed that soot particles could bind 2.3 to 50.2% of formaldehyde, depending on the particle size, relative humidity, amount of particles and the duration of the contact. The recovery of formaldehyde from the particles was also tested. Further investigation is planned under realistic conditions.     

环境标准实施中的若干问题

探讨了目前环境标准在制订、发行、宣贯过程中存在的问题 ,并就规范环境标准发布、加强标准宣贯等提出建议