Transition of human and livestock waste management in rural Hanoi: a material flow analysis of nitrogen and phosphorus during 1980–2010

Journal of Material Cycles and Waste Management - Human and livestock waste, i.e., excreta, were intensively used in crop cultivation in Asia over the years. However, rapid economic growth induced...     

Deposition and Storage of Spheroidal Carbonaceous Fly-Ash Particles in European Mountain Lake Sediments and Catchment Soils

Spheroidal carbonaceous particles(SCPs) are produced only from high temperaturecombustion of fossil-fuels. In mountain lakesystems, they provide an unambiguous indicator ofatmospheric deposition. In order to comparedepositional fluxes of SCPs between mountainareas experiencing various pollutant regimes,intensive bulk deposition sampling was undertakenat five sites across Europe. Catchment soil coresand lake sediment cores were also taken at eachsite to compare SCP storage over the post-industrial period. Atmospheric, sediment and soilSCP data showed similar patterns. Highestcontamination was found in Scotland, Slovakia andSpain with the Austrian site intermediate and themid-Norwegian site least contaminated. A highproportion of accumulated SCPs were found to bestored in catchment soils at each site.Therefore, a significant increase in soilerosion, possibly as a result of future climatechange, could lead to the input of largequantities of catchment stored SCPs and, byimplication, other atmospherically depositedcontaminants to the lake ecosystem.     

Trends in the Water Chemistry of High Altitude Lakes in Europe

Here we present the chemical trends of seven high altitude lakes, analysed within the AL:PE and MOLAR Projects of the EU (1999) and selected on the basis of the availability of complete and reliable data for the period 1984–1999. The lakes are representative of the Scandinavian Alps, the Cairngorm Mountains in Scotland, the Alps and the Pyrenees. Significant trends were identified for some indicators of acidification, for instance pH and alkalinity, but not all lakes reacted similarly to decreasing depositions of sulphate and base cations. Differences in lake response are discussed in relation to recent variations of atmospheric deposition chemistry and associated changes in climatic conditions. Beside individual variations of the studied lakes, depending, among other things, on altitude and morphology, catchment characteristics and climate trends play a major role for the reaction of high altitude lakes on changes in atmospheric depositions.     

Exposure Programme on Atmospheric Corrosion Effects of Acidifying Pollutants in Tropical and Subtropical Climates

Many national exposure programmes have been performed in tropical and subtropical climates during the last 50 years. However, ambitious programmes involving more than a few countries are scarce. In this paper a recently formed network of test sites is described involving 12 test sites in Asia (India, Vietnam, Thailand, Malaysia and China including Hong Kong) and four test sites in Africa (South Africa, Zambia and Zimbabwe). This effort is part of the 2001–2004 Swedish International Development Agency (SIDA) funded Programme on Regional Air Pollution in Developing Countries (RAPIDC). Corrosion attack after one (2002–2003) year of exposure (carbon steel, zinc, copper, limestone and paint coated steel) are presented together with environmental data (SO₂, NO₂, HNO₃, O₃, particles, amount and pH of precipitation, temperature and relative humidity) for all the test sites. The obtained corrosion values are substantially higher than expected for limestone, higher than expected for carbon steel and lower than expected for zinc compared to values calculated using the best available dose–response functions.     

Recovering Food Commons in Post Industrial Europe: Cooperation Networks in Organic Food Provisioning in Catalonia and Norway

This paper explores food commoning through an ethnographic case study in Catalonia as our primary site while the Norwegian case is juxtaposed as a comparison, two agriculturally and economically different European countries. The ethnography analyses cooperation networks between organic food producers’ and consumers’ involving different nodes of community gardening initiatives, self-employed growers, local farmers and all of them under a unique cooperative integrating a community economy. The result it is a myriad of exchange practices ranging from reciprocity and barter to market exchange without intermediaries through on-line platforms. Along these exchanges different options of currency intervene giving rise to novel social and cooperative relations. Similar initiatives in Norway show less variation and are less experimental regarding forms of payment but share similarities in relation to material articulations, concerns and forms of alternative practice. Although these novel forms do not represent a complete break from the more standardized supply chains, and hence from the oppositions/contradictions of production and consumption, the participants see themselves as contributing to a more general process of de-commodification of food. We explore the extent to which the meaning and moral values are mutually constituted in relation to socioeconomic exchanges and environmental caring that each person experiences based on different forms of cooperation and reciprocity. Food, we suggest, is more than a commodity on the market that we may influence through our role as consumers. It is a significant focal point connecting our lives to those of others that articulates one’s relations to society in a political manner.     

Arbuscular mycorrhizal fungi can decrease the uptake of uranium by subterranean clover grown at high levels of uranium in soil

Subterranean clover inoculated or not with the arbuscular mycorrhizal (AM) fungus Glomus intraradices was grown on soil containing six levels of 238U in the range 0-87 mg kg(-1). Increasing U concentration in soil enhanced the U concentration in roots and shoots of both mycorrhizal and nonmycorrhizal plants but had no significant effects on plant dry matter production or root AM colonization. Mycorrhizas increased the shoot dry matter and P concentration in roots and shoots, while in most cases, it decreased the Ca, Mg and K concentrations in plants. The AM fungus influenced U concentration in plants only in the treatment receiving 87 mg U kg(-1) soil. In this case, U concentration in shoots of nonmycorrhizal plants was 1.7 times that of shoots of mycorrhizal plants. These results suggested that mycorrhizal fungi can limit U accumulation by plants exposed to high levels of U in soil.     

High-level arsenite removal from groundwater by zero-valent iron

The objectives of this study were to conduct batch and column studies to (i) assess the effectiveness of zero-valent iron for arsenic remediation in groundwater, (ii) determine removal mechanisms of arsenic, and (iii) evaluate implications of these processes with regard to the stability of arsenic and long-term remedial performance of the permeable reactive barrier (PRB) technology. A high concentration arsenic solution (50 mg l(-1)) was prepared by using sodium arsenite (arsenic (III)) to simulate groundwater at a heavily contaminated Superfund site in the USA. Batch studies indicate that the removal of arsenic is a two-step reaction with fast initial disappearance of arsenite followed by a slow subsequent removal process. Flow-through columns were conducted at a flow rate of 17 ml h(-1) under reducing conditions for 6.6 mo. Kinetic analysis suggested that arsenic removal behaves as a zero-order reaction at high arsenic concentrations. Arsenic removal rate constants decreased with time and arsenic breakthrough was observed in the column study. Arsenic removal capacity of zero-valent iron was determined to be approximately 7.5 mg As/g Fe. Carbonate green rust was identified from the analysis of surface precipitates; arsenite uptake by green rust may be a major mechanism responsible for arsenic remediation by zero-valent iron. Analysis of HCl-extractable arsenic from iron samples indicated that approximately 28% of arsenic was in the form of arsenate suggesting that a surface oxidation process was involved in the arsenic removal with zero-valent iron.     

Bimetallic iron-aluminum particles for dechlorination of carbon tetrachloride

Bimetallic iron-aluminum (Fe/Al) particles were synthesized and tested for their reactivity toward carbon tetrachloride using batch reactors and a flow-through column at near neutral pH. Preparation of bimetallic Fe/Al particles was conducted under acidic conditions under which iron was readily deposited onto the aluminum surface. The SEM image showed clusters of iron on the aluminum surface at the measured Fe:Al molar ratio of about 2:3. Results showed that the presence of zero-valent aluminum successfully prevented the formation of a passive layer at the iron surface and maintained the reactivity of iron. The dechlorination of carbon tetrachloride by bimetallic Fe/Al particles produced chloroform (9%), dichloromethane (17%) and methane (38%). Kinetic analysis suggests that bimetallic Fe/Al particles increased the reactivity toward carbon tetrachloride degradation by a factor of 10 compared to zero-valent iron and possessed a comparable reactivity with nano-sized Fe. The effectiveness of bimetallic Fe/Al particles was further confirmed by the continuous flow column study from which an ageing of bimetallic particles was also observed.     

On-site rainwater harvesting and treatment for drinking water supply: assessment of cost and technical issues

Environmental Science and Pollution Research - This study assessed the performance of rainwater-harvesting systems installed for selected public utilities in the northern provinces of Vietnam where...     

Norwegian farmers ceasing certified organic production: Characteristics and reasons

This article examines the characteristics of and reasons for Norwegian farmers’ ceasing or planning to cease certified organic production. We gathered cross-sectional survey data in late 2007 from organic farmers deregistering between January 2004 and September 2007 (n = 220), and similar data from a random sample of farmers with certified organic management in 2006 (n = 407). Of the respondents deregistering by November 2007, 17% had quit farming altogether, 61% now farmed conventionally, and 21% were still farming by organic principles, but without certification. Nearly one in four organic farmers in 2007 indicated that they planned to cease certification within the next 5–10 years. From the two survey samples, we categorised farmers who expect to be deregistered in 5–10 years into three groups: conventional practices (n = 139), continuing to farm using organic principles (uncertified organic deregistrants, n = 105), and stopped farming (n = 33). Of the numerous differences among these groups, two were most striking: the superior sales of uncertified organic deregistrants through consumer-direct marketing and the lowest shares of organic land among conventional deregistrants. We summarised a large number of reasons for deregistering into five factors through factor analysis: economics, regulations, knowledge-exchange, production, and market access. Items relating to economics and regulations were the primary reasons offered for opting out. The regression analysis showed that the various factors were associated with several explanatory variables. Regulations, for example, figured more highly among livestock farmers than crop farmers. The economic factor strongly reflected just a few years of organic management. Policy recommendations for reducing the number of dropouts are to focus on economics, environmental attitudes, and the regulatory issues surrounding certified organic production.