Energy transition and its implications for environmentally sustainable development in Africa

SUMMARY

Energy transition is the process whereby there is an increase in the volume and proportion of commercial energy, to the extent that it replaces traditional fuels as the main source of energy and having enormous implications for the physical and biotic environment. This energy-environment process has rarely been the focus of research investigation in Africa. Using cross-national data drawn from the African continent, this paper examines and accounts for intercountry variations in the nature and extent of the energy transition process. The empirical analysis reveals that, for the continent as a whole, the extent to which commercial energy replaces traditional fuels is quite low. It varies between 33% and 39%. However, inter-country variations were found to be as high as 90% in countries such as Algeria, Egypt, Libya, Mauritania, Morocco and South Africa; and less than 15% for such countries as Benin, Burkina Faso, The Central African Republic, Ethiopia, Lesotho and Uganda. The key factors explaining intercounty variations in the energy transition process are the level of urbanization and the extent of forest and woodland resources. Other factors of secondary importance include economic growth, incidence of poverty, affordability of electrical appliances, energy trade status of the country in question and the price of commercial fuel. Finally, the paper shows that the identification of these key energy transition-inducing variables is a necessary prerequisite to an effective energy and environmentally sustainable development policy formulation in Africa.     

Behavioural,emotional, and cognitive responses in European disasters: results of survivor interviews

In the European multi‐centre study BeSeCu (Behaviour, Security, Culture), interviews were conducted in seven countries to explore survivors’ emotional, behavioural, and cognitive responses during disasters. Interviews, either in groups or one‐to‐one, were convened according to type of event: collapse of a building; earthquake; fire; flood; and terror attack. The content analysis of interviews resulted in a theoretical framework, describing the course of the events, behavioural responses, and the emotional and cognitive processing of survivors. While the environmental cues and the ability to recognise what was happening varied in different disasters, survivors’ responses tended to be more universal across events, and most often were adaptive and non‐selfish. Several peri‐traumatic factors related to current levels of post‐traumatic stress were identified, while memory quantity did not differ as a function of event type or post‐traumatic stress. Time since the event had a minor effect on recall. Based on the findings, several suggestions for emergency training are made.     

Singing onstage: female and male common nightingales eavesdrop on song type matching

In bird communication, listening individuals may obtain information on the quality and motivation of a male not only from solo-singing, but also from song interactions and listeners base their future decisions in territorial and mating contexts on such public information. Eavesdropping on male interactions may thus have a strong influence on sexual selection. In singing interactions, temporal coordination (e.g. overlapping vs. alternating) of two singers as well as structural interaction patterns (e.g. song type matching or repertoire matching) have been described, but the latter is far less studied. By conducting dual-speaker playback experiments with common nightingales Luscinia megarhynchos, we simulated an interaction where one singer was repeatedly song–type matching his counterpart. Playbacks were broadcast to male and female nightingales, and their approach behaviour and singing responses (in the case of male focals) were analysed. We found that both, males and females, spent more time with the matched bird, whereas males additionally sang more songs towards the matching bird. This can be taken as strong hint that eavesdropping occurs in nightingale communication and that listening to male vocal contests might be an important strategy for both sexes to adjust their behavioural output. With regard to the function of song matching, we assume that song-matching is not an aggressive signal per se in nightingales. We rather conclude that vocal leaders within an interaction, here the matched bird, may elicit stronger responses in conspecifics than vocal followers, here the matching bird.     

夏季珠江口叶绿素a和营养盐分布特征及其与环境因子的关系

本研究基于2019年夏季珠江口附近海域的现场调查数据,分析了珠江口叶绿素a（chlorophyll a,Chl a）和营养盐的分布特征,并结合环境因子进行了探讨。结果表明:夏季珠江口海域表层Chl a和溶解氧（dissolved oxygen,DO）浓度分别为4.192～88.209 μg/L和4.610～10.586 mg/L;溶解无机氮（dissolved inorganic nitrogen,DIN）、活性磷酸盐（PO₄-P）和活性硅酸盐（SiO₃-Si）浓度分别为0.168～1.247 mg/L、0.011～0.044 mg/L和0.694～6.916 mg/L。夏季珠江口浮游植物生长旺盛,依据美国河口营养状况评价（NEEA-ASSETS）标准,44.4%的站位处于高度富营养化（20 μg/L60 μg/L）。珠江径流量是夏季珠江口浮游植物空间分布的主要驱动因素,珠江口口门内浮游植物生长受光限制和径流稀释影响并未出现高值,珠江口口门外浮游植物旺发消耗了大量磷酸盐,磷成为浮游植物生长的限制因子。Chl a与盐度、PO₄-P呈显著负相关性,与DIN、DIN/P呈显著正相关性,表明河口冲淡水对浮游植物生长影响显著。     

天津地区冬季总悬浮颗粒物中PAHs污染特征

采集并分析了天津不同区县13个样点冬季总悬浮颗粒物(TSP)中16种优控多环芳烃(PAHs)含量.结果表明不同样品间PAHs含量差异明显,东部开发区和中北部区县含量明显高于其它地区,大港油田的颗粒物中PAHs含量很低,市区、南部区县和北部山区居中.根据毒性等效因子计算了等效浓度,不同样品PAHs总等效浓度差异不大,占总浓度50%的高环PAHs毒性贡献达90%.     

Agricultural production and bird conservation in complex landscapes of the dry Chaco

The South American dry Chaco is a mosaic of woody vegetation and grasslands with high deforestation rates in recent decades. Considering forests and grasslands as the main natural habitats, we assessed the trade-offs between bird populations and agricultural production to compare the potential consequences of different land use strategies (‘sharing’, ‘sparing’, and intermediate) for populations of bird species sensitive to agriculture, while attaining a regional production target. We evaluated how populations responded to scenarios with different proportions of forest and grasslands, considering three reference states (100% forest, 80:20% and 50:50% forest and grasslands, respectively); and scenarios capable of meeting three after-farming scenarios, with land destined to reach a regional production target with three variations of forest:grasslands within spared land. We fitted curves to relate bird abundance to agricultural yield along a gradient of meat production intensity; and we classified bird species as ‘losers’ (if their populations were lower than the baseline population in the reference state, at any level of production) and ‘winners’ (if their current populations were higher than the baseline population). At the ‘current’ (c. 2010) level of regional agricultural production, we found a similar number of loser species maximized by land-sparing and land-sharing strategies; while intermediate strategies were the least favourable to balance production and bird populations. Under the most probable scenarios of increases in regional meat production, most loser bird species populations were maximized by a land-sparing strategy, suggesting that if meat production targets are going to increase in the region, this can be more efficiently achieved by combining well-protected forests and grasslands, and high-yielding mechanized agriculture (e.g. soybean). Our results highlight the importance of assessing all the important natural habitats (e.g. forests and grasslands) of a region to explore conservation strategies at a regional scale.     

Perfluorooctanoic acid and perfluorooctane sulfonate released from a waste water treatment plant in Bavaria, Germany

Purpose

Perfluorooctanoate (PFOA), perfluorooctane sulfonate (PFOS), and precursors and derivatives thereof have been employed as surfactants and anti-adhesives. PFOA and PFOS are environmentally persistent and the discharge of municipal waste waters is one of the principal routes of these compounds into the aquatic environment. In a previous study, the concentrations of PFOA and PFOS in grab samples collected from the waste water treatment plant (WWTP) of Bayreuth, a city of 72,000 inhabitants in Bavaria, Germany, during two periods showed considerable variability. For a better estimate of average mass flows, the surfactants were monitored (five samplings) from 16 March to 18 May 2007. In a second campaign, river water receiving the WWTP effluent was sampled twice a day for five consecutive days.

Methods

Quantitative analysis was done by stable-isotope dilution, pre-cleaning, and pre-concentration by solid-phase extraction, and liquid chromatography followed by electrospray ionization/tandem mass spectrometry.

Results

The mass flows of PFOA and PFOS through the WWTP were determined. PFOA is fully discharged into the river, while about half of PFOS is retained in the sewage sludge. The average daily mass load of the river Roter Main by the WWTP of Bayreuth is about 1.2?±?0.5 g PFOA and 5?±?2 g PFOS, with variations of up to 140% within one day.

Conclusion

Overall, the total annual release to the rivers of Germany may be in the range of several hundred kilograms of PFOA and several tons of PFOS.     

A theory of chemicals regulation and testing

Risk management of chemicals requires information about their adverse effects such as toxicity and persistence, for example. Testing of chemicals allows for improving the information base for regulatory decision‐making on chemicals' production and use. Testing a large number of chemicals with limited time and resources forces a prioritization of chemicals. This paper proposes a decision model that provides a ranking of chemicals according to “urgency to test”. The model adopts a value‐of‐information approach describing the expected welfare gains from regulatory actions that respond to test information. We determine the value‐of‐information of tests revealing chemicals' levels of toxicity and persistence. We compare our findings to the prioritization of chemicals in the new European Chemicals Regulation “REACH”, where several tens of thousands of chemicals are to be tested in order to fill existing information gaps and to implement more effective risk management. We find that the main lines of chemicals' prioritization under REACH receive backing from our decision model. However, prioritization for testing can be further improved by accounting for testing costs and the sensitivity of regulatory action with respect to the test information.     

中国太阳能热水器成本分析方法与应用研究

太阳能热水器在中国已经商业化,是较为成熟的可再生能源利用技术。中国幅员辽阔,各地区自然、社会经济条件差异较大,其经济可行性需进一步分析。本文针对户用太阳能热水器,建立了基于有效利用热量的总成本现值分析方法、净成本现值分析方法,计算了中国27个省会城市(或直辖市)太阳能热水器热水供应成本和净成本现值为零的初始投资。结果表明,中国太阳能热水器热水供应成本地区间差异大,推广政策应当因地制宜;太阳能热水器与风电、光伏发电、生物质能发电相比成本较低,其大规模应用有利于以低成本实现既定的可再生能源目标;贴现率和生活电价对太阳能热水器初始投资选择影响显著;收入水平低是农村地区太阳能热水器应用的重要制约因素。本文的结论对中国太阳能热水器推广政策体系设计具有重要启示。     

协同学视角下的生态工业园结构研究

首先,按照协同学划分子系统的要求,将生态工业园划分成推力子系统、内部子系统及拉力子系统.然后,从各子系统对生态工业园稳定性的作用力角度,进一步研究了各子系统的组成结构.研究表明推力子系统作用力由政府支持、经济支持、资源支持及市场支持构成,内部子系统作用力由技术充足、成员多样、关键种企业、合作距离、信息平台、空间距离、领导因素及企业关联度组成,生态效率为拉力子系统作用力.