Mitigation of global greenhouse gas emissions from waste: conclusions and strategies from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report. Working Group III (Mitigation).

Greenhouse gas (GHG) emissions from post-consumer waste and wastewater are a small contributor (about 3%) to total global anthropogenic GHG emissions. Emissions for 2004-2005 totalled 1.4 Gt CO2-eq year(-1) relative to total emissions from all sectors of 49 Gt CO2-eq year(-1) [including carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and F-gases normalized according to their 100-year global warming potentials (GWP)]. The CH4 from landfills and wastewater collectively accounted for about 90% of waste sector emissions, or about 18% of global anthropogenic methane emissions (which were about 14% of the global total in 2004). Wastewater N2O and CO2 from the incineration of waste containing fossil carbon (plastics; synthetic textiles) are minor sources. Due to the wide range of mature technologies that can mitigate GHG emissions from waste and provide public health, environmental protection, and sustainable development co-benefits, existing waste management practices can provide effective mitigation of GHG emissions from this sector. Current mitigation technologies include landfill gas recovery, improved landfill practices, and engineered wastewater management. In addition, significant GHG generation is avoided through controlled composting, state-of-the-art incineration, and expanded sanitation coverage. Reduced waste generation and the exploitation of energy from waste (landfill gas, incineration, anaerobic digester biogas) produce an indirect reduction of GHG emissions through the conservation of raw materials, improved energy and resource efficiency, and fossil fuel avoidance. Flexible strategies and financial incentives can expand waste management options to achieve GHG mitigation goals; local technology decisions are influenced by a variety of factors such as waste quantity and characteristics, cost and financing issues, infrastructure requirements including available land area, collection and transport considerations, and regulatory constraints. Existing studies on mitigation potentials and costs for the waste sector tend to focus on landfill CH4 as the baseline. The commercial recovery of landfill CH4 as a source of renewable energy has been practised at full scale since 1975 and currently exceeds 105 Mt CO2-eq year(-1). Although landfill CH4 emissions from developed countries have been largely stabilized, emissions from developing countries are increasing as more controlled (anaerobic) landfilling practices are implemented; these emissions could be reduced by accelerating the introduction of engineered gas recovery, increasing rates of waste minimization and recycling, and implementing alternative waste management strategies provided they are affordable, effective, and sustainable. Aided by Kyoto mechanisms such as the Clean Development Mechanism (CDM) and Joint Implementation (JI), the total global economic mitigation potential for reducing waste sector emissions in 2030 is estimated to be > 1000 Mt CO2-eq (or 70% of estimated emissions) at costs below 100 US$ t(-1) CO2-eq year(-1). An estimated 20-30% of projected emissions for 2030 can be reduced at negative cost and 30-50% at costs < 20 US$ t(-) CO2-eq year(-1). As landfills produce CH4 for several decades, incineration and composting are complementary mitigation measures to landfill gas recovery in the short- to medium-term--at the present time, there are > 130 Mt waste year(-1) incinerated at more than 600 plants. Current uncertainties with respect to emissions and mitigation potentials could be reduced by more consistent national definitions, coordinated international data collection, standardized data analysis, field validation of models, and consistent application of life-cycle assessment tools inclusive of fossil fuel offsets.     

Estimating reduction of nitrogen leaching from arable land and the related costs

The EU Water Framework Directive will require river-basin management plans in order to achieve good ecological status and find the most cost-efficient nitrogen (N) leaching abatement measures. Detailed scenario calculations based on modeling methods will be valuable in this regard. This paper describes the approach and an application with a coefficient method based on the simulation model SOILNDB for quantification of N leaching from arable land and for prediction of the effect of abatement scenarios for the R?nne? catchment (1900 km2) in southern Sweden. Cost calculations for the different measures were also performed. The results indicate that the individual measures-cover crop and spring plowing, late termination of ley and fallow, and spring application of manure-would only reduce N leaching by between 5% and 8%. If all measures were combined and winter crops replaced by their corresponding spring variants, a 21% reduction in N leaching would be possible. However, this would require total fulfillment of the suggested measures.     

Urban road-traffic noise and blood pressure and heart rate in preschool children

Night time noise exposure has very rarely been used in previous studies on the relationship between community noise and children's blood pressure, although children spend a larger part of their night time sleeping at home than adults. For this reason, we focused on night time noise exposure at children's residences and daytime noise at kindergartens. The aim of this study was to investigate the effects of urban road-traffic noise on children's blood pressure and heart rate. A cross-sectional study was performed on 328 preschool children (174 boys and 154 girls) aged 3-7 years, who attended 10 public kindergartens in Belgrade. Equivalent noise levels (Leq) were measured during night in front of children's residences and during day in front of kindergartens. A residence was regarded noisy if Leq exceeded 45 dB (A) during night and quiet if the Leq was < or =45 dB (A). Noisy and quiet kindergartens were those with daily Leq>60 dB (A) and < or =60 dB (A), respectively. Children's blood pressure was measured with mercury sphygmomanometer. Heart rate was counted by radial artery palpitation for 1 min. The prevalence of children with hypertensive values of blood pressure was 3.96% (13 children, including 8 boys and 5 girls) with higher prevalence in children from noisy residences (5.70%), compared to children from quiet residences (1.48%). The difference was borderline significant (p=0.054). Systolic pressure was significantly higher (5 mm Hg on average) among children from noisy residences and kindergartens, compared to children from both quiet environments (p<0.01). Heart rate was significantly higher (2 beats/min on average) in children from noisy residences, compared to children from quiet residences (p<0.05). Multiple regression, after allowing for possible confounders, showed a significant correlation between noise exposure and children's systolic pressure (B=1.056; p=0.009).     

Tree species diversity and its relationship to stand parameters and geomorphology features in the eastern Black Sea region forests of Turkey

We studied the effects of stand parameters (crown closure, basal area, stand volume, age, mean stand diameter number of trees, and heterogeneity index) and geomorphology features (elevation, aspect and slope) on tree species diversity in an example of untreated natural mixed forest stands in the eastern Black Sea region of Turkey. Tree species diversity and basal area heterogeneity in forest ecosystems are quantified using the Shannon-Weaver and Simpson indices. The relationship between tree species diversity basal area heterogeneity stand parameters and geomorphology features are examined using regression analysis. Our work revealed that the relationship between tree species diversity and stand parameters is loose with a correlation coefficient between 0.02 and 0.70. The correlation of basal area heterogeneity with stand parameters fluctuated between 0.004 and 0.77 (R2). According to our results, stands with higher tree species diversity are characterised by higher mean stand diameter number of diameter classes, basal area and lower homogeneity index value. Considering the effect of geomorphology features on tree species or basal area heterogeneity we found that all investigated relationships are loose with R < or = 0.24. A significant correlation was detected only between tree species diversity and aspect. Future work is required to verify the detected trends in behaviour of tree species diversity if it is to estimate from the usual forest stand parameters and topography characteristics.     

Atmospheric mercury at mediterranean coastal stations

Mercury in air has been measured at five coastal Mediterranean sites, involving measurements in Spain, France, Italy, Slovenia and Israel. Four two-weeks long measurements campaigns were performed at the five sites. The measurements were carried out during autumn 2003 and winter, spring and summer 2004. Total gaseous mercury/elemental gaseous mercury, particulate mercury and divalent gaseous mercury were measured in parallel at the five sites. The activities constituted a subtask of the EU funded MERCYMS research project, which also included Mediterranean Sea cruises where both mercury in air and water were measured. The result from an evaluation of all the coastal air data is presented. Mercury concentrations from the different sites are compared with similar data obtained in northern Europe and elsewhere. The result shows that the background concentration of mercury in Mediterranean coastal air is lower than earlier anticipated. Background concentrations of TGM, RGM and TPM corresponded to 1.75–1.80 ng m⁻³, 1–13 and 3–23 pg m⁻³, respectively. The measurements also showed that the mercury concentration occasionally can be very high in some areas due to local anthropogenic emissions. It is proposed that diurnal variation in RGM concentrations observed during situation with nocturnal inversion merely is an effect of meteorology rather than due to local photochemistry.     

Trends in seasonal precipitation and temperature in Slovenia during 1951–2007

A quality-controlled and enhanced database of 38 temperature and 52 precipitation stations was developed for Slovenia, a transitional area between Mediterranean, Alpine and continental climatic regimes, covering the period 1951–2007. Mean annual temperatures significantly increased in nearly all of Slovenia (except western areas) at rates between 0.15 and 0.36 °C/decade. Warming was most intense strongest in summer and spring in north-eastern Slovenia (0.3–0.4 °C/decade) and weakest in autumn. Precipitation trends were heterogeneous. Annual precipitation decreased significantly in the north-western part, at 3–6 % per decade. During spring and summer, decrease in rainfall by 3–6 % was detected in western Slovenia. No significant trends were found for the autumn season. In winter, precipitation decreased, by 3–12 % per decade, in particular in north-western Slovenia. As observed also elsewhere in Central Europe, changes in large-scale atmospheric circulation patterns may have contributed to the observed long-term warming and drying in Slovenia. However, the strong warming in summer and spring, that is almost twice the trend observed in neighbouring countries, could be enhanced by drier soils caused by the decrease in winter precipitation in Slovenia.     

Imazethapyr persistence in sandy loam detected using white mustard bioassay

Field experiments were conducted during two years at Srem region to investigate the influence of meteorological conditions, time and rate of application on soil persistence of imazethapyr in sandy loam type of soil. Imazethapyr was applied PRE- and POST-EM and in both cases in three application rates: 80, 120 and 160 g a.i./ha. Soil samples were collected from the day of herbicide application in predetermined intervals up to one year after application and residual concentrations were determined with a white mustard root bioassay. Imazetapyr persistence was significantly influenced by meteorological conditions with average half-life being 6 days longer in season with lower precipitation level. Time of application induced slower imazethapyr dissipation resulting in higher average t_1/2 (seven and nine days in first and second year of examination, respectively). Application rates had no consistent effect on imazethapyr persistence. Imazethapyr residue level one year after application caused no visible injuries on white mustard shoots, while root growth reduction ranged from 4.6 to 27.7%. Obtained residue levels were further compared with known data on crop sensitivity in order to assess possibility of crop injuries one year after imazethapyr application.     

A landscape vulnerability analysis method proposal and its integration in the EIA

Landscape is the area primarily affected by proposed human projects. The prediction and evaluation of the potential anthropogenic impacts under Environmental Impact Assessment (EIA) is therefore one of the major environmental tools for prevention of any deteriorative or destructive actions. To conduct EIA properly requires inclusion of a determination of landscape vulnerability which expresses the possible landscape reaction to impacts of any exogenous factors. When it is designated correctly, the suitable human activities are determined more accurately. Even though many techniques for this have been suggested worldwide, lots of deficiencies have surfaced in their application. This paper presents a method for landscape vulnerability analysis which consists of qualitative evaluation of landscape receptors, their scoring, the vulnerability degree calculation, and overall reliability evaluation. The method proposed can improve the impact objectivity of prediction and evaluation and the suggestion of precise mitigation measures with the purpose of achieving sustainable landscape management.     

Cost-Effective Control of Interdependent Water Pollutants

Excess nutrient loads to coastal waters lead to increased production of algae, which when decaying cause oxygen depletion in bottom sediments, which in turn leads to major changes in marine ecosystems. A cost-minimization model was investigated in which nitrogen and phosphorus were assumed to interact with respect to algae production. It was investigated under what conditions only a single nutrient should be decreased and when it is cost-effective to decrease both nutrients. The model was applied to the Baltic Proper, which is the largest of the seven major basins in the Baltic Sea. Results showed that the stringency of the environmental target, as well as assumptions regarding substitutability between nutrients, are important factors to determine the nutrient on which to focus. Uniform decrease rates for emissions are often used in international agreements, and the results of this model showed that the costs of making such proportional decreases could be substantial.