Using phytoremediation technologies to upgrade waste water treatment in Europe

Goal, Scope and Background One of the burning problems of our industrial society is the high consumption of water and the high demand for clean drinking water. Numerous approaches have been taken to reduce water consumption, but in the long run it seems only possible to recycle waste water into high quality water. It seems timely to discuss alternative water remediation technologies that are fit for industrial as well as less developed countries to ensure a high quality of drinking water throughout Europe. Main Features The present paper discusses a range of phytoremediation technologies to be applied in a modular approach to integrate and improve the performance of existing wastewater treatment, especially towards the emerging micro pollutants, i.e. organic chemicals and pharmaceuticals. This topic is of global relevance for the EU. Results Existing technologies for waste water treatment do not sufficiently address increasing pollution situation, especially with the growing use of organic pollutants in the private household and health sector. Although some crude chemical approaches exist, such as advanced oxidation steps, most waste water treatment plants will not be able to adopt them. The same is true for membrane technologies. Discussion Incredible progress has been made during recent years, thus providing us with membranes of longevity and stability and, at the same time, high filtration capacity. However, these systems are expensive and delicate in operation, so that the majority of communities will not be able to afford them. Combinations of different phytoremediation technologies seem to be most promising to solve this burning problem. Conclusions To quantify the occurrence and the distribution of micropollutants, to evaluate their effects, and to prevent them from passing through wastewater collection and treatment systems into rivers, lakes and ground water bodies represents an urgent task for applied environmental sciences in the coming years. Recommendations Public acceptance of green technologies is generally higher than that of industrial processes. The EU should stimulate research to upgrade existing waste water treatment by implementing phytoremediation modules and demonstrating their reliability to the public.     

Picophytoplankton responses to changing nutrient and light regimes during a bloom

The spring bloom in seasonally stratified seas is often characterized by a rapid increase in photosynthetic biomass. To clarify how the combined effects of nutrient and light availability influence phytoplankton composition in the oligotrophic Gulf of Aqaba, Red Sea, phytoplankton growth and acclimation responses to various nutrient and light regimes were recorded in three independent bioassays and during a naturally-occurring bloom. We show that picoeukaryotes and Synechococcus maintained a “bloomer” growth strategy, which allowed them to grow quickly when nutrient and light limitation were reversed. During the bloom picoeukaryotes and Synechococcus appeared to have higher P requirements relative to N, and were responsible for the majority of photosynthetic biomass accumulation. Following stratification events, populations limited by light showed rapid photoacclimation (based on analysis of cellular fluorescence levels and photosystem II photosynthetic efficiency) and community composition shifts without substantial changes in photosynthetic biomass. The traditional interpretation of “bloom” dynamics (i.e., as an increase in photosynthetic biomass) may therefore be confined to the upper euphotic zone where light is not limiting, while other acclimation processes are more ecologically relevant at depth. Characterizing acclimation processes and growth strategies is important if we are to clarify mechanisms that underlie productivity in oligotrophic regions, which account for approximately half of the global primary production in the ocean. This information is also important for predicting how phytoplankton may respond to global warming-induced oligotrophic ocean expansion.     

A novel method for reducing acid mine drainage using green liquor dregs

When exposed to the weather, sulfidic minerals release sulfuric acid, metals and metalloids. This leachate can devastate nearby ecosystems for centuries. This article reports a novel barrier system based on green liquor dregs that reduces acid generation, is inexpensive, and is practical for implementation at operational mines. Two waste rock piles were constructed. One pile was left open to the atmosphere, and the other was sealed with green liquor dregs and partially capped with a polyethylene liner. This test was designed in collaboration with personnel from Boliden Mineral AB, a Swedish mining company in order to ensure that the results would be practical to implement at an operational mine. Leachate flow and chemistry were monitored in both piles over a period of 12 months. Effluent volume was 40 % lower in the test pile, while thirteen of the twenty elements assessed showed average concentrations that were 50 % lower in the test pile than in the control pile. For the most environmentally toxic elements As, Cd, Pb and Hg, reductions were even more significant, ranging between 67 and 87 %. These positive results are hypothesized to be primarily due to the chemical and physical characteristics of the green liquor dregs. The novelty of this result is that it is the first barrier system that fulfills the multiple needs of the Swedish mining industry: It is effective in reducing acid mine drainage while remaining both economical and practical. No other barrier system meets these requirements.     

Ecological Impact of Economic Development on Sardinian Herpetofauna

The link between ecology and economies is manifest over the world as a result of long-term processes. But because these processes are long term, it is hard to prove the link. On Sardinia serious economic development was late to arrive, having occurred only over the last few decades. As a case study, research was carried out for 10 years on the state of nature as well as the economic growth in one of the least developed areas abutting the Gulf of Orosei on the east coast. Based on research and lasting attention to political affairs concerning the project, we formulate general recommendations for the area. In 1995, the Italian Government will be asked by the European Government to undertake serious steps to save endemics (especially herpetofauna) of Europe's last pristine areas.     

Costs of food waste along the value chain: Evidence from South Africa

In a previous paper (Nahman et al., 2012), the authors estimated the costs of household food waste in South Africa, based on the market value of the wasted food (edible portion only), as well as the costs of disposal to landfill. In this paper, we extend the analysis by assessing the costs of edible food waste throughout the entire food value chain, from agricultural production through to consumption at the household level. First, food waste at each stage of the value chain was quantified in physical units (tonnes) for various food commodity groups. Then, weighted average representative prices (per tonne) were estimated for each commodity group at each stage of the value chain. Finally, prices were multiplied by quantities, and the resulting values were aggregated across the value chain for all commodity groups. In this way, the total cost of food waste across the food value chain in South Africa was estimated at R61.5 billion per annum (approximately US$7.7 billion); equivalent to 2.1% of South Africa’s annual gross domestic product. The bulk of this cost arises from the processing and distribution stages of the fruit and vegetable value chain, as well as the agricultural production and distribution stages of the meat value chain. These results therefore provide an indication of where interventions aimed at reducing food waste should be targeted.     

Real-time monitoring of water quality using fish and crayfish as bio-indicators: a review

Water quality monitoring using fish and crayfish as bio-indicators requires an understanding of the state of pollution of waters, choice of bio-indicators, physiological and behavioral endpoints of fish and crayfish, and principles of the methodology and their potential applications. Here, we discuss telemetry, acoustic monitoring, vision-based monitoring, measures of ventilatory activity, electrocardiography, and fiber-optic plethysmography. Assessment of water quality must be based, not only on physicochemical characteristics of the current environment as determined by chemical analyses, but also on observations of the physiology and behavior of its inhabitants. Real-time biomonitoring is suggested as the most reliable method, since it incorporates living organisms into the system to serve as biosensors. The potential application of the methods discussed includes use at water treatment plants and water supply stations for prevention of hazardous toxicological events, and, for aquaculture, in ponds, lakes, and aquariums for monitoring growth, population size, and behavior traits.