Formation and weathering assessment of oil-suspended sediment aggregates through a laboratory investigation

Environmental Science and Pollution Research - Formation of oil-suspended sediment aggregates (OSAs) is believed to be one of the natural cleaning processes in the marine environment. In this...     

Biodiversity Differences between Managed and Unmanaged Forests: Meta-Analysis of Species Richness in Europe

Abstract: Past and present pressures on forest resources have led to a drastic decrease in the surface area of unmanaged forests in Europe. Changes in forest structure, composition, and dynamics inevitably lead to changes in the biodiversity of forest‐dwelling species. The possible biodiversity gains and losses due to forest management (i.e., anthropogenic pressures related to direct forest resource use), however, have never been assessed at a pan‐European scale. We used meta‐analysis to review 49 published papers containing 120 individual comparisons of species richness between unmanaged and managed forests throughout Europe. We explored the response of different taxonomic groups and the variability of their response with respect to time since abandonment and intensity of forest management. Species richness was slightly higher in unmanaged than in managed forests. Species dependent on forest cover continuity, deadwood, and large trees (bryophytes, lichens, fungi, saproxylic beetles) and carabids were negatively affected by forest management. In contrast, vascular plant species were favored. The response for birds was heterogeneous and probably depended more on factors such as landscape patterns. The global difference in species richness between unmanaged and managed forests increased with time since abandonment and indicated a gradual recovery of biodiversity. Clearcut forests in which the composition of tree species changed had the strongest effect on species richness, but the effects of different types of management on taxa could not be assessed in a robust way because of low numbers of replications in the management‐intensity classes. Our results show that some taxa are more affected by forestry than others, but there is a need for research into poorly studied species groups in Europe and in particular locations. Our meta‐analysis supports the need for a coordinated European research network to study and monitor the biodiversity of different taxa in managed and unmanaged forests.     

Fecundity of the freshwater fish Channa punctatus (Bloch) from three aquatic bodies

The fecundity studies on Channa punctatus revealed that there is a relationship between length of the fish with fecundity, weight of the fish and ovary with fecundity. The length and fecundity exhibit curvilinear relationship and a straight line relationship is observed between fecundity and body weight. Fecundity and ovary weight also exhibited linear relationship. The comparative degree of fecundity of the fish is Jagat tank > Kadaganchi tank > Kagina river. Although fish collected from Jagat tank exhibits higher fecundity, all the other three aquatic bodies provide proper environmental conditions for the growth and reproductive activity of the fish.     

The Evolution and Role of Non-OPEC Production in the International Oil Market

In 1982, for the first time since OPEC was founded in 1961, its production was surpassed by the non-OPEC countries in the world excluding the centrally planned economies. In that year, for the world as a whole, OPEC provided 35% of the oil consumed. The decline was brought about by a decrease in consumption and by a marked increase in production from non-OPEC sources. It is expected that non-OPEC producers will have the capacity to meet more than half of the world's oil requirements until the early 1990s, at which time OPEC producers will again assume the role of providing over 50% of the world's oil.     

Algae Biomass Based Media for Poly(3-hydroxybutyrate) (PHB) Production by Escherichia coli

In addition to biodiesel production from algae, the production of other valuable bioproducts facilitates the development of an algae-based biorefinery platform. The goal of this study was to utilize the aqueous fraction from a novel algal wet lipid extraction procedure as the medium for the production of a bio product, poly(3-hydroxybutyrate) (PHB), via the growth of recombinant Escherichia coli. PHB yield was measured at 34 % of the E. coli dry cell mass, and was increased to 51 % when the algae aqueous medium was supplemented with glucose. While the addition of inorganic nutrients to the aqueous phase did not increase PHB production or growth of E. coli, growth of E. coli was observed to increase with the supplementation of carbon substrate (glucose). The addition of carbon rich waste to the aqueous fraction of wastewater-derived algae may in the future provide a sustainable alternative. Future research will be directed at evaluating this concept to develop a sustainable process for the production of bioplastics through an algae-based biorefinery platform.     

渤海湾两条河流及其近岸海域水体中DOM的光谱特征及影响因素

应用三维荧光光谱结合吸收光谱分析,研究了2019年夏季天津市大清河-独流减河水系和河北省黄骅市捷地减河及其河口区水体中溶解有机物（DOM）的空间分布特征、来源及其影响因素。紫外-可见光谱结果表明,研究区水体的SUVA₂₅₄与盐度有显著正相关关系;两条河流的下游水体中S_275-295均值均大于上游和中游。平行因子分析结果表明,两条河流均检测到两种类腐殖质组分C1（240,300/390 nm）和C3（260,335/477 nm）以及一种类蛋白质组分C2（225,275/339 nm）。在大清河-独流减河水系及其近岸海域水体中,这三种组分与盐度呈显著负相关关系,其中由于人为输入（TN和TP含量高,工业排污）影响导致C2与盐度的相关性弱于C1和C3。该水系水体在低盐度时C2的占比高于捷地减河,主要受到工农业废水输入与其支流子牙河汇入的共同影响,而捷地减河主要受农业废污水输入的影响。此外,自然因素（盐度、海水混合）和人为因素（人为输入、筑坝拦截）的不同导致渤海湾两条入海河流中有色溶解有机质（CDOM）的光学特性和混合行为出现显著差异。其中筑坝拦截导致独流减河坝前水体的CDOM平均分子量低于下游水体,并且增强了河口区陆源类腐殖质的去除作用。综上,三维荧光光谱结合平行因子分析能判别河流局部条件的差异对整体CDOM空间分布特征的影响,研究结果可为渤海湾地区河流及河口水体CDOM生物地球化学过程研究提供基础数据。     

基于游客视角的红色旅游资源开发价值共创机制

以井冈山风景名胜区作为案例地,基于价值共创理论,运用大数据分析与内容分析方法,收集并分析马蜂窝网站上井冈山景区的游记文本,构建红色旅游资源开发的价值共创机制：以历史文化遗产、自然景观资源和标志性景观符号为资源基础,游客通过红色文化体验、学习培训活动、解说服务体验和自然景观体验等实践活动,获得对红色历史文化的认知、情感的联结和价值观的塑造。另外,红色旅游景区现有的价值共创实践仍旧有限,红色旅游资源开发价值共创机制整合了游客需求、景区支持以及可能存在的价值共创实践,对创新红色旅游资源开发利用手段与产业转型升级具有实践意义。     

Developments in inherent safety: A review of the progress during 2001–2011 and opportunities ahead

This paper reviews the progress in inherent safety. A summary of the historical developments up to the year 2000 is first presented which sets the stage for a review of the key developments during the first 11 years of the 21st century. A landscape of inherent safety is developed by mapping publications on two coordinates. The first coordinate, the risk coordinate, indicates if the focus of a paper relates to inherent hazard or to the likelihood of events. The second coordinate, the management coordinate, focuses on the ways and means to understand and assess inherent safety. Out of the 187 papers that have appeared over this 11-year period, 131 pertained to developments in inherently safer design; these have been organized on the proposed landscape. The rest introduce the basic concepts of inherent safety and address its incorporation into regulation, education and accident investigation. These along with the application of inherent safety in industry are also discussed. We conclude with a discussion on recent trends in industry and suggest directions for future research.     

Nationwide indoor 222Rn and 220Rn map for India: a review

Considering the role of radon in epidemiology, an attempt was made to make a nation-wide map of indoor ²²²Rn and ²²⁰Rn for India. More than 5000 measurements have been carried out in 1500 dwellings across the country comprising urban and nonurban locations. The solid state nuclear track detectors based twin cup ²²²Rn/²²⁰Rn discrimination dosimeters were deployed for the measurement of indoor ²²²Rn, ²²⁰Rn and their progeny levels. The geometric means of estimated annual inhalation dose rate due to indoor ²²²Rn, ²²⁰Rn and their progeny in the dwellings was 0.94 mSvy⁻¹ (geometric standard deviation 2.5). It was observed that the major contribution to the indoor inhalation dose was due to indoor ²²²Rn and its progeny. However, the contribution due to indoor ²²⁰Rn and its progeny was not trivial as it was found to be about 20% of the total indoor inhalation dose rates. The indoor ²²²Rn levels in dwellings was significantly different depending on the nature of walls and floorings.