Reactive nitrogen and the world: 200 years of change

This paper examines the impact of food and energy production on the global N cycle by contrasting N flows in the late-19th century with those of the late-20th century. We have a good understanding of the amounts of reactive N created by humans, and the primary points of loss to the environment. However, we have a poor understanding of nitrogen's rate of accumulation in environmental reservoirs, which is problematic because of the cascading effects of accumulated N in the environment. The substantial regional variability in reactive nitrogen creation, its degree of distribution, and the likelihood of increased rates of reactive-N formation (especially in Asia) in the future creates a situation that calls for the development of a Total Reactive Nitrogen Approach that will optimize food and energy production and protect environmental systems.     

After 35 years,have we made progress: A government perspective

The use of irradiation to improve the safety, protect the nutritional benefits, and preserve the quality of fresh and processed foods is a well established and proven technology. Over the past 35 years, the United States Government has invested in the science to confirm safety and in the technology to show application. The United States Department of Agriculture (USDA) and the Food and Drug Administration have approved sources of ionizing radiation for the treatment of foods, and their application to most meats, fruits, vegetables, and spices. Despite the value of this technology to the food industry and to the health and welfare of the public, only minimal application of this technology occurs. This underscores the importance of increasing the public's understanding of radiation risks relative to other hazards. Accordingly, in 1995, the Committee on Interagency Radiation Research and Policy Coordination of the Executive Office of the President made recommendations for the creation of a centralized National Radiation Information Center that would work closely with Federal departments and agencies in responding to public queries about radiation issues and Federal programs. This article updates a commentary published in 1996 (Young 1996). In the past six years, some progress has been made, including the establishment of a government operated Food Irradiation Information Center, and the completion of final rule making by USDA, thus permitting the safe treatment of meats and poultry. Despite these actions, little progress has been made on the public acceptance of this technology. The need for an informed public and for a better understanding of risks, i.e., risk communication, is noted.     

The Swedish monitoring of surface waters: 50 years of adaptive monitoring

For more than 50 years, scientific insights from surface water monitoring have supported Swedish evidence-based environmental management. Efforts to understand and control eutrophication in the 1960s led to construction of wastewater treatment plants with phosphorus retention, while acid rain research in the 1970s contributed to international legislation curbing emissions. By the 1990s, long-time series were being used to infer climate effects on surface water chemistry and biology. Monitoring data play a key role in implementing the EU Water Framework Directive and other legislation and have been used to show beneficial effects of agricultural management on Baltic Sea eutrophication. The Swedish experience demonstrates that well-designed and financially supported surface water monitoring can be used to understand and manage a range of stressors and societal concerns. Using scientifically sound adaptive monitoring principles to balance continuity and change has ensured long-time series and the capability to address new questions over time.     

Thirty years of land-cover change in Bolivia

Land-cover change in eastern lowland Bolivia was documented using Landsat images from five epochs for all landscapes situated below the montane tree line at approximately 3000 m, including humid forest, inundated forest, seasonally dry forest, and cloud forest, as well as scrublands and grasslands. Deforestation in eastern Bolivia in 2004 covered 45,411 km2, representing approximately 9% of the original forest cover, with an additional conversion of 9042 km2 of scrub and savanna habitats representing 17% of total historical land-cover change. Annual rates of land-cover change increased from approximately 400 km2 y(-1) in the 1960s to approximately 2900 km2 y(-1) in the last epoch spanning 2001 to 2004. This study provides Bolivia with a spatially explicit information resource to monitor future land-cover change, a prerequisite for proposed mechanisms to compensate countries for reducing carbon emissions as a result of deforestation. A comparison of the most recent epoch with previous periods shows that policies enacted in the late 1990s to promote forest conservation had no observable impact on reducing deforestation and that deforestation actually increased in some protected areas. The rate of land-cover change continues to increase linearly nationwide, but is growing faster in the Santa Cruz department because of the expansion of mechanized agriculture and cattle farms.     

Kosetice, Czech Republic--ten years of air pollution monitoring and four years of evaluating the origin of persistent organic pollutants

The regional observatory Kosetice is a central European background station. Unique continuous monitoring from 1988 on is held here. POP (persistent organic pollutant) concentration values of air samples from Kosetice taken between 1996 and 2005 were statistically processed. Values of Czech ambient air quality standards were not exceeded. Concentrations of polycyclic aromatic hydrocarbons reached two maxima, in 1996 and 2001-2002. Polychlorinated biphenyls concentrations reached the highest values in 1997 and 1998 and hexachlorocyclohexanes concentrations in 1998. DDTs, hexachlorobenzene and pentachlorobenzene were analysed as well. Long-range transport of pollutants between 2002 and 2005 was evaluated using the Potential Source Contribution Function hybrid receptor model. Indicated potential source areas of PCBs coincide with many well-known urban and industrialised areas, while the indicated potential source areas of HCHs and DDTs coincide with many agricultural and/or forested regions and the potential source areas of HCB comprise all land use types.     

Effects of ozone on grain quality of wheat grown in open-top chambers: three years of experimentation

Field trials with winter wheat (Triticum aestivum L.) grown in open-top chambers and exposed to either ambient filtered (F) or unfiltered (NF) air were carried out for 3 years in northern Italy. The experiments were performed at two places, a rural and an urban site in the Po Plain. The data obtained show no significant difference in protein, starch and glucose contents between the treatments; nevertheless, a tendency towards an increase in glucose and a decrease in starch contents was observed in the F chambers compared with NF. In addition, potassium levels were lower in F than in NF treatment, while calcium were higher. Ozone levels observed in the Po Valley are not sufficiently high to cause significant differences in quality parameters of winter wheat.     

Acid rain and air pollution: 50 years of progress in environmental science and policy

Because of its serious large-scale effects on ecosystems and its transboundary nature, acid rain received for a few decades at the end of the last century wide scientific and public interest, leading to coordinated policy actions in Europe and North America. Through these actions, in particular those under the UNECE Convention on Long-range Transboundary Air Pollution, air emissions were substantially reduced, and ecosystem impacts decreased. Widespread scientific research, long-term monitoring, and integrated assessment modelling formed the basis for the policy agreements. In this paper, which is based on an international symposium organised to commemorate 50 years of successful integration of air pollution research and policy, we briefly describe the scientific findings that provided the foundation for the policy development. We also discuss important characteristics of the science–policy interactions, such as the critical loads concept and the large-scale ecosystem field studies. Finally, acid rain and air pollution are set in the context of future societal developments and needs, e.g. the UN’s Sustainable Development Goals. We also highlight the need to maintain and develop supporting scientific infrastructures.

     

Cancer and occupational exposure to pesticides: a bibliometric study of the past 10 years

Environmental Science and Pollution Research - Occupational exposure to pesticides has been identified as a major trigger of the development of cancer. Pesticides can cause intoxication in the...     

Still present after all these years: persistence plus potential toxicity raise questions about the use of atrazine

As one of the worlds’ most heavily applied herbicides, atrazine is still a matter of controversy. Since it is regularly found in ground and drinking water, as well as in sea water and the ice of remote areas, it has become the subject of continuous concern due to its potential endocrine and carcinogenic activity. Current findings prove long-held suspicions that this compound persists for decades in soil. Due to the high amount applied annually all over the world, the soil burden of this compound is considered to be tremendous, representing a potential long-term threat to the environment. The persistence of chemicals such as atrazine has long been underestimated: Do we need to reconsider the environmental risk?     

Cold start extra emissions as a function of engine stop time: Evolution over the last 10 years

Cars with catalysts show a significant increase in exhaust emissions at engine start. These extra emissions are expressed as the difference, over a particular driving cycle, between emissions generated when the vehicle is started and when the engine or the catalyst are stably warm. Experimental data, suitable for the assessment of cold start emissions, are usually available for completely cooled engines. Most results originate from tests at ambient temperature of 20–30 °C and with an engine stop time of at least 12 h. On the other hand, data including shorter stop times are very rare.The present work investigates the influence of exhaust emissions with shorter stop times, i.e. 0.5, 1, 2 and 4 h. The main goal consists in the comparison of emissions exhausted by recent car models (Euro-4) against emissions assessed in the framework of a similar campaign 10 years ago (FAV1/Euro-1 vehicles).A short survey of the current extra emission estimation methods is presented in this paper. It is shown that some methods are not suited for providing correct estimations in all cases. We discuss the fact that different estimation methods can show either similar or completely different results depending on the evolution behaviour of the hot emissions.Due to new technologies, e.g. the catalyst and improved engine control algorithms, emissions have been considerably reduced over the last 10 years. In this study it is determined how the relative extra emissions, i.e. extra emissions relative to the extra emissions for the standard stop time of 12 h, expressed as a function of stop time have changed. We may claim with caution that for medium stop times of 0.5–4 h the average relative extra emissions of Euro-4 vehicles are well below the average of the relative extra emissions of Euro-1 vehicles.     

White clover clones as a cost-effective indicator of phytotoxic ozone: 10 years of experience from central Italy

Data collected at one site in central Italy using the NC-S/NC-R clover (Trifolium repens) biotype system during 1997-2007 were analysed in order to assess: (a) its performance under Mediterranean conditions; (b) variations of ozone damage linked with meteorological conditions; (c) if critical level approach is a good predictor of ozone risk on vegetation. NC-S dry biomasses were systematically lower than those of NC-R, the mean ratio being 0.7. Relevant relationship between ozone visible injury and cumulated values of AOT40 were also reported. Temperature and number of rainy days were the most important factors associated with ozone presence and, as a consequence, with leaf injury index. Photosynthetic gas exchange properties indicate that NC-S has higher values of stomatal conductance.     

Two years of oil disaster in the Arabian Gulf

In January–February 1991, about 1 million m³ of crude oil were released into the Arabian Gulf as a means of ecological warfare. A stretch of 644 km along the Saudi Arabian coast was heavily polluted over a width between a few meters and more than one kilometer. In four studies performed between March 1991 and April 1993 the state of representative areas of the affected coast was examined with the result that only minor changes were found in those oiled zones which are seldom inundated by the tides. Technical measures up to 1993 did not exceed the test level. A biological regeneration process is in progress which was not recognized as such in analyses of previous coastal oil pollution. Cyanobacterial mats, containing hydrocarbon-degrading bacteria, grow on oiled sediments which are regularly reached by tidal water. Shrinking and fracturing of the stable tar crusts starts a process of loosening and degrading of aged hydrocarbons.     

Impact of vertical transport processes on the tropospheric ozone layering above Europe.: Part II: Climatological analysis of the past 30 years

Using the set of multivariate criteria described in a companion paper, ozone-rich layers detected in tropospheric soundings are clustered according to their stratospheric or boundary layer origin. An additional class for aged tropospheric air masses is also considered. This analysis is exclusively based on the measured physical properties of the layers. The database includes 27,000 ozone profiles collected above 11 European stations—two of which provide measurements since 1970. The seasonal cycle of the tropospheric ozone stratification exhibits a clear summer maximum. This increase is due to aged tropospheric air masses that are more frequently detected, suggesting an enhanced lifetime of layers in summer. In terms of ozone content, the relative impact of stratospheric ozone compared to the other sources is highest in winter while export from the boundary layer presents a uniform seasonal cycle. Altitude and thickness distributions of the layers are consistent with the dynamical processes involved in the layering. Northernmost and southernmost stations are more exposed to stratospheric air intrusions into the free troposphere. Long-term trends show that transport from the tropopause region has increased since the mid 1980s. This trend being concomitant with lower ozone content of such layers, a moderate trend of the transport efficiency from the stratosphere on total tropospheric ozone is observed. The increase of ozone detected in tropospheric layers since the mid 1980s cannot be attributed to any recent export process from either the stratosphere or the boundary layer but rather to enhanced photochemical production in aged air masses or to an increase in the lifetime of the layers.     

Variations in source apportionments of nutrient load among seasons and hydrological years in a semi-arid watershed: GWLF model results

Quantifying source apportionments of nutrient load and their variations among seasons and hydrological years can provide useful information for watershed nutrient load reduction programs. There are large seasonal and inter-annual variations in nutrient loads and their sources in semi-arid watersheds that have a monsoon climate. The Generalized Watershed Loading Function model was used to simulate monthly nutrient loads from 2004 to 2011 in the Liu River watershed, Northern China. Model results were used to investigate nutrient load contributions from different sources, temporal variations of source apportionments and the differences in the behavior of total nitrogen (TN) and total phosphorus (TP). Examination of source apportionments for different seasons showed that point sources were the main source of TN and TP in the non-flood season, whereas contributions from diffuse sources, such as rural runoff, soil erosion, and urban areas, were much higher in the flood season. Furthermore, results for three typical hydrological years showed that the contribution ratios of nutrient loads from point sources increased as streamflow decreased, while contribution ratios from rural runoff and urban area increased as streamflow increased. Further, there were significant differences between TN and TP sources on different time scales. Our findings suggest that priority actions and management measures should be changed for different time periods and hydrological conditions, and that different strategies should be used to reduce loads of nitrogen and phosphorus effectively.     

Global trends and status in waste foundry sand management research during the years 1971-2020: a systematic analysis

Environmental Science and Pollution Research - Waste foundry sand (WFS) is the by-product of the foundry industry, which is produced about 0.6 tons per 1 ton of foundry industry production. While...     

The Scottish Raptor Monitoring Scheme: objectives, achievements in the first four years, and plans for future development

The Scottish Raptor Monitoring Scheme (SRMS) comprises 7 partner organizations and was established in 2002 after i) the publication of the UK Government's Raptor Working Group Report that made recommendations for enhanced monitoring, ii) increased applied data needs (e.g., for site designation), and iii) concerns for the status of some species. The SRMS has 3 major objectives: i) to facilitate cooperation between parties; ii) to provide robust information on Scottish raptor populations by determining trends in numbers, range, survival, and productivity and understanding the causes of change; and iii) to maintain high and uniform standards for the collection, collation, auditing, and analysis of data and reporting of information. Data are collected for 19 species: 14 diurnal raptors, 4 owls, and 1 corvid, the Common Raven. Here we describe the development of the scheme, challenges, and achievements during its first 4 y, the nature and value of the data collected, and plans for the future.