Characterization of phosphate rock and phosphogypsum from Gabes phosphate fertilizer factories (SE Tunisia): high mining potential and implications for environmental protection

Environmental Science and Pollution Research - Since the establishment of the coastal industrial complex in Gabes city (Gulf of Gabes, SE Tunisia), hundred million tons of untreated phosphogypsum...     

Potential of Eucalyptus globulus for the phytoremediation of metals in a Moroccan iron mine soil—a case study

Environmental Science and Pollution Research - The contamination left by abandoned mines demands sustainable mitigation measures. Hence, the aim of this study was to examine the phytoremediator...     

Living within fallen palm leaves: the discovery of an unknown Blommersia (Mantellidae: Anura) reveals a new reproductive strategy in the amphibians of Madagascar

We describe a new mantelline frog of the genus Blommersia found in rainforest in North East Madagascar, from the protected areas of Ambatovaky, Betampona, Masoala, and Zahamena. Blommersia angolafa n.sp. is a small frog, with a body size of 17–21 mm, expanded finger and toe tips, and colouration ranging from yellow to dark brown, with pale-bluish spots on the flanks and light tips of fingers and toes. A peculiar aspect characterising this new species is its novel life history and reproductive mode. Both sexes live and breed in a phytotelmic habitat of water accumulated within fallen prophylls and fallen leaf sheaths of at least three species of Dypsis palms. Within these phytotelmata, egg laying and complete larval development occur. Thus, B. angolafa n.sp. represents a new evolutionary lineage of Malagasy frogs in which phytotelmy is known. Up to now, reproduction in phytotelmata in Malagasy frogs has been reported for many cophyline microhylids, most species of Guibemantis, Mantella laevigata, and possibly in a still-undescribed species belonging to the genus Spinomantis. We consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding strategy. The new species, being specialised to a habitat represented by a few selected Dypsis species, potentially suffers the selective exploitation of these palms.     

The Adaptive Capacity Wheel: a method to assess the inherent characteristics of institutions to enable the adaptive capacity of society

Climate change potentially brings continuous and unpredictable changes in weather patterns. Consequently, it calls for institutions that promote the adaptive capacity of society and allow society to modify its institutions at a rate commensurate with the rate of environmental change. Institutions, traditionally conservative and reactive, will now have to support social actors to proactively respond through planned processes and deliberate steps, but also through cherishing and encouraging spontaneous and autonomous change, as well as allowing for institutional redesign. This paper addresses the question: How can the inherent characteristics of institutions to stimulate the capacity of society to adapt to climate change from local through to national level be assessed? On the basis of a literature review and several brainstorm sessions, this paper presents six dimensions: Variety, learning capacity, room for autonomous change, leadership, availability of resources and fair governance. These dimensions and their 22 criteria form the Adaptive Capacity Wheel. This wheel can help academics and social actors to assess if institutions stimulate the adaptive capacity of society to respond to climate change; and to focus on whether and how institutions need to be redesigned. This paper also briefly demonstrates the application of this Adaptive Capacity Wheel to different institutions.     

MAP沉淀法目标产物最优形成条件及分析方法

为了确定鸟粪石(MAP：MgNH₄PO₄·6H₂O)形成的最优条件,引入化学剖析法,利用酸溶液将鸟粪石沉淀法中所得沉淀物溶解后进行相应的元素分析;提出一种根据沉淀物中的NH⁺₄-N含量间接计算确定鸟粪石含量(即纯度)的分析方法.根据这种计算分析方法,分别得出了不同pH条件下以自来水(主要为地下水)和超纯水作为溶剂所合成的鸟粪石纯度,并对pH和Ca²⁺在鸟粪石形成过程中的影响进行了评估.结果表明,该计算分析方法能够有效实现对MAP沉淀法目标产物的定量分析,弥补了国内外目前普遍依靠XRD技术定性判断所得沉淀物中鸟粪石是否存在的缺陷.以超纯水作为溶剂时,使鸟粪石纯度>90%的最佳pH范围在7.5～9.0,而以自来水为溶剂时,获得相同鸟粪石纯度最佳pH范围则是7.0～7.5.实际污水中常常含有相当数量的Ca²⁺,实施碱性条件(pH>8.0)的MAP沉淀势必大幅降低鸟粪石的纯度.因此,对实际污水回收磷而言,MAP沉淀法的最优pH条件应控制在中性范围(<8.0)以内.     

European scale application of atmospheric reactive nitrogen measurements in a low-cost approach to infer dry deposition fluxes

A European scale network was established in 2006 as part of the NitroEurope Integrated Project to infer reactive nitrogen (Nr) dry deposition fluxes, based on low-cost sampling of gaseous and aerosol species and inferential modelling. The network provides monthly measurements of NH₃, NH₄⁺, HNO₃ and NO₃⁻, as well as SO₂, SO₄²⁻, HCl, Cl⁻ and base cations at 58 sites. Measurements are made with an established low-cost denuder methodology (DELTA) as a basis to: (1) examine temporal trends and spatial patterns across Europe, (2) improve and calibrate inferential modelling techniques to estimate exchange of Nr species, (3) provide best estimates of atmospheric dry N deposition, and (4) permit an analysis of net GHG exchange in relation to atmospheric and agricultural N inputs at the European scale. Responsibility for measurements is shared among seven European laboratories. An inter-comparison of the DELTA implementation by 6 laboratories at 4 test sites (Montelibretti, Italy; Braunschweig, Germany; Paterna, Spain and Auchencorth, UK) from July to October 2006 provided training for the laboratories and showed that good agreement was achieved in different climatic conditions (87% of laboratory site-means within 20% of the inter-laboratory median). Results obtained from the first year of measurements show substantial spatial variability in atmospheric Nr concentrations, illustrating the major local (NH₃) and regional (HNO₃, NO₃⁻, and NH₄⁺) differences in Nr concentrations. These results provide the basis to develop future estimates of site-based Nr dry deposition fluxes across Europe, and highlight the role of NH₃, largely of agricultural origin, which was the largest single constituent and will dominate dry Nr fluxes at most sites.     

Increasing land pressure in East Africa: The changing role of cassava and consequences for sustainability of farming systems

Increasing land pressure during the past three to four decades has transformed farming systems in the mid-altitude zone of East Africa. Traditional millet-, cotton-, sugarcane- and/or banana-based farming systems with an important fallow and/or grazing component have evolved into continuously cultivated cassava or cassava/maize-based systems. Within three to four decades, cassava cultivation increased from 1–11 to 16–55% of cropped fields in our six study sites. Declining soil fertility, and not labour or food shortage, was apparently the primary trigger for this transformation. The land use changes have increased nutrient offtakes and reduced nutrient recycling rates. Cassava and maize now account for 50–90% of nutrient removal. Whereas single-season fallows were the most important source of nutrient recycling on cropped fields in the past, currently cassava litterfall and maize stover contribute roughly 70% of nutrient recycling, with 50–70% of N, P and K recycled in cassava litterfall. This may explain why many farmers reason that cassava ‘rests’ the soil. With increasing land use pressure farmers progressively use cassava as an ‘imitation fallow’ throughout their farm. Farmers increasingly target cassava to poor fertility fields characterized by low pH and available P. High cassava intensities are nonetheless maintained on more fertile fields, probably to guarantee regeneration of soil fertility on all fields. Once cassava is targeted to poor fertility soils, farmers have run out of low-input management options and need to intensify management to maintain system productivity. As cassava is now used by more farmers and on a larger acreage than fallowing in the studied farming systems, cassava cropping could perhaps serve as an excellent entry point to strengthen system sustainability.     

石油污染土壤物化修复前后生物毒性效应

采用作物种子的发芽率作为生态指标对石油污染土壤进行毒性分析,并以蚯蚓为实验生物,研究了石油污染物的生物效应及其对土壤生态系统的影响.结果表明,不同的作物种子对石油污染表现出不同的耐受性,对照清洁土壤,大多数作物种子的萌发都明显受到石油污染的抑制,其中受石油污染影响最严重的是黄豆、蚕豆、玉米.相比之下,在不同石油污染水平下绿豆具有较高的耐受性,且种子发芽率均在90%以上.蚯蚓在受到污染胁迫时,在生理水平上会发生明显的变化,进而影响其存活和生长能力,实验观测到随着石油污染加重蚯蚓存活时间显著下降.在高污染水平石油污染的土壤中(石油污染水平>30 000 mg.kg-1),蚯蚓的耐性降低,仅可以存活5 d左右,说明石油烃对蚯蚓的毒性较大,主要是因为蚯蚓直接与石油接触导致其中毒脱水而死亡.处理后油田污染土,即使在污染水平很低(≈30 mg.kg-1)的情况下,蚯蚓存活时间依然很短(3 d左右),是因为经过石油醚处理过的土壤,其营养物质也随着石油而被处理掉,而土壤中有机质等营养物对蚯蚓的生存具有很大影响.     

Climate change and economic consequences for inland waterway transport in Europe

Future climate conditions are likely to affect inland waterway transport in Europe. According to some climate scenarios, in summer, in the river Rhine, periods with low water levels are likely to occur more often and become more serious. Then inland waterway transport carriers will experience more severe restrictions on the load factor of their inland ships, which implies a stronger reduction in transport capacity in the market. Transport prices will rise under such conditions. Some studies reviewed in this paper find that at extremely low water levels, the price per tonne for inland waterway transport in the river Rhine area will almost double. These increased transport prices result in welfare losses. For the dry summer in 2003, the losses for North West Europe are estimated to sum up to around €480 million. Increased transport prices trigger adaptation. Inland waterway carriers may use smaller vessels, and shippers have the opportunity to shift from inland waterway transport to alternative transport modes in periods with low water levels. This effect is probably rather modest, however, with a modal shift to road and rail smaller than 10 %. Also, changes in transport costs may lead to relocation of certain economic activities in the long run.     

Adaptation options for marine industries and coastal communities using community structure and dynamics

Identifying effective adaptation strategies for coastal communities dependent on marine resources and impacted by climate change can be difficult due to the dynamic nature of marine ecosystems. The task is more difficult if current and predicted shifts in social and economic trends are considered. Information about social and economic change is often limited to qualitative data. A combination of qualitative and quantitative models provide the flexibility to allow the assessment of current and future ecological and socio-economic risks and can provide information on alternative adaptations. Here, we demonstrate how stakeholder input, qualitative models and Bayesian belief networks (BBNs) can provide semi-quantitative predictions, including uncertainty levels, for the assessment of climate and non-climate-driven change in a case study community. Issues are identified, including the need to increase the capacity of the community to cope with change. Adaptation strategies are identified that alter positive feedback cycles contributing to a continued decline in population, local employment and retail spending. For instance, the diversification of employment opportunities and the attraction of new residents of different ages would be beneficial in preventing further population decline. Some impacts of climate change can be combated through recreational bag or size limits and monitoring of popular range-shifted species that are currently unmanaged, to reduce the potential for excessive removal. Our results also demonstrate that combining BBNs and qualitative models can assist with the effective communication of information between stakeholders and researchers. Furthermore, the combination of techniques provides a dynamic, learning-based, semi-quantitative approach for the assessment of climate and socio-economic impacts and the identification of potential adaptation strategies.