Areawide Trace Metal Concentrations Measured by Multielement Neutron Activation Analysis

A suite of 24 hour high volume air particulate samples, collected June 11–12,1969, at 25 locations in the Northwest Indiana area, has been analyzed by nondestructive neutron activation analysis for 30 trace elements. The use of Ge(Li) gamma-ray spectrometry and computer assisted data reduction, combined with 2-4 replications of each analysis, yielded precise results which allowed a study of the geographical distribution patterns of the elements. Some elements, such as Na, K, Ti, Al, Sm, and Eu, show only minor concentration variations over the area,while others, such as Cu, W, Cr, Zn, Sb, Ga, Br, Ag, Fe, and Ce, show large variations, indicative of important local sources. Similar distribution patterns and high correlation coefficients suggest common sources for several elements. The variations of most heavy elements significantly exceed previously reported variations of total particulate, indicating the latter to be an unsatisfactory guide for elemental distribution, especially near pollution sources. Three representative locations for measurement of elemental abundances in the area are suggested. The influence of meteorological conditions and the potential Lake Michigan pollution hazard are discussed     

Mercury Concentration in the Atmosphere in Chicago A New Ultrasensitive Method Employing Amalgamation

During the past two years, the Chicago Department of Environmental Control chemistry laboratory has developed a prototype sensor for measuring low levels of mercury found in the free or ambient atmosphere. Earlier studies of mercury in the Chicago area postulated that most of the mercury in the atmosphere should condense onto particulates and be collectable on filters. The results of the work presented here show that this may not occur. Analysis of composites of Chicago high volume particulate filters results in an average of 4 nanograms/m³ (range 2-10 nanograms/m³). This compared with a typical average of elemental mercury measurements of 22 nanograms/m³ (range 5-60 nanograms/m³). Thus, it is obvious that particulate borne mercury, at least as analyzed from a high volume filter paper, is not as significant as the total or elemental mercury existing in the metropolitan area. A direct method for collecting mercury and measuring in a flameless atomic absorption unit yields very good results.     

Characterization and Classification of Atmospheric Sulfates

Atmospheric sulfates are currently a topic of considerable interest. This arises primarily from their possible association with adverse health effects,1 and from their undoubted importance in the acid rain problem.²

Knowledge of the sulf ate species present in airborne particulates is essential to a full appreciation of the sources of aerosol sulfate constituents and to an understanding of respiratory health hazards. Charlson and coworkers³ have recently reviewed the current state of knowledge of the chemical nature of tropospheric Sulfur aerosols. It is clear from Charlson’s review that firm evidence exists for the presence of only a very few specific sulfate compounds in the atmosphere, and that much of our current thought is based upon inference and supposition.³     

A Life-Cycle Inventory Model of Municipal Solid Waste Combustion

ABSTRACT

Evaluation of alternate strategies for municipal solid waste (MSW) management requires models to calculate environmental emissions as a function of both waste quantity and composition. A methodology to calculate waste component-specific emissions associated with MSW combustion is presented here. The methodology considers emissions at a combustion facility as well as those avoided at an electrical energy facility because of energy recovered from waste combustion. Emission factors, in units of kg pollutant per metric ton MSW entering the combustion facility, are calculated for CO₂-biomass, CO₂-fossil, SO_x , HCl, NO_x , dioxins/furans, PM, CO, and 11 metals. Water emissions associated with electrical energy offsets are also considered. Reductions in environmental emissions for a 500-metric-ton-per-day combustion facility that recovers energy are calculated.     

Climate Change and Water Resources in Arid Mountains: An Example from the Bolivian Andes

Climate change is projected to have a strongly negative effect on water supplies in the arid mountains of South America, significantly impacting millions of people. As one of the poorest countries in the region, Bolivia is particularly vulnerable to such changes due to its limited capacity to adapt. Water security is threatened further by glacial recession with Bolivian glaciers losing nearly half their ice mass over the past 50 years raising serious water management concerns. This review examines current trends in water availability and glacier melt in the Bolivian Andes, assesses the driving factors of reduced water availability and identifies key gaps in our knowledge of the Andean cryosphere. The lack of research regarding permafrost water sources in the Bolivian Andes is addressed, with focus on the potential contribution to mountain water supplies provided by rock glaciers.     

Perspectives on area-based conservation and its meaning for future biodiversity policy

During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of “living in harmony with nature.” We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision.     

Prospects of inspection and maintenance of two-wheelers in India.

Two-wheeler vehicles in Delhi, India--roughly 70% of the total vehicle fleet--are responsible for a significant portion of the city's vehicle emissions and petroleum consumption. An inspection and maintenance (I/M) program that ensures vehicle emission control systems are well maintained can complement other emission reduction strategies. This paper presents the initial findings of extensive data collected on vehicle characteristics and emissions for two-wheeler vehicles operating in Delhi in a series of I/M camps conducted by the Society of Indian Automobile Manufacturers and various partners in late 1999. The analysis shows idle HC and CO emissions [measured in terms of parts per million (ppm) and volume % (vol %), respectively] in a slow declining trend with subsequent model years, reflecting tighter emission standards and more advanced emission technologies. The I/M benefits--3 vol % and 39% reduction in idle and mass CO, respectively; 40 vol % and 22% reduction in idle and mass HC, respectively; and a 10-20% increase in fuel efficiency--were higher than those reported in the literature. Although these benefits are substantial, any implementation strategy needs to consider cost-effectiveness. In the present study, only 10% of vehicles--contributing 22% of the total vehicle emissions--failed the idle CO standard. Fleet emissions data variability necessitates a large sample size to develop a baseline for the vehicle fleet, but a smaller, scientifically designed sample and better data collection quality could periodically track the benefits at future camps.     

Landholder Profiling and Typologies for Natural Resource–Management Policy and Program Support: Potential and Constraints

The use of landholder typologies to aid the development, implementation, and monitoring natural-resource management (NRM) policies and programs has increased considerably during the past decade. This article explores the potential for using such typologies for a variety of NRM and rural and regional development applications. Review of typology use further suggests that there is potential to refine the way that typologies are developed and applied to better aid NRM, farming systems analyses, and rural and regional development. Before typologies will be adopted more widely, a number of theoretical and methodologic issues must be addressed. These include the following questions: (1) Which criteria and methods should or can be used to classify landholders? (2) How should studies across spatial and temporal scales be integrated? (3) How should multiple and single industry studies be integrated to gain the most value from research? We argue that quantitative research techniques are well suited to provide an underlying structure for landholder typologies, and qualitative research techniques are useful for developing understanding of the nature of variation within and between landholder types. We argued further that because of the potential utility and breadth for the application of landholder typologies, a nested set of landholder typologies could be developed that are coordinated at the national, regional, and local geographic levels, with repeated measures used to track the evolution with time of landholder practices, management values, and socioeconomic characteristics.     

Impacts of hunting on tropical forests in Southeast Asia

Although deforestation and forest degradation have long been considered the most significant threats to tropical biodiversity, across Southeast Asia (Northeast India, Indochina, Sundaland, Philippines) substantial areas of natural habitat have few wild animals (>1 kg), bar a few hunting‐tolerant species. To document hunting impacts on vertebrate populations regionally, we conducted an extensive literature review, including papers in local journals and reports of governmental and nongovernmental agencies. Evidence from multiple sites indicated animal populations declined precipitously across the region since approximately 1980, and many species are now extirpated from substantial portions of their former ranges. Hunting is by far the greatest immediate threat to the survival of most of the region's endangered vertebrates. Causes of recent overhunting include improved access to forests and markets, improved hunting technology, and escalating demand for wild meat, wildlife‐derived medicinal products, and wild animals as pets. Although hunters often take common species, such as pigs or rats, for their own consumption, they take rarer species opportunistically and sell surplus meat and commercially valuable products. There is also widespread targeted hunting of high‐value species. Consequently, as currently practiced, hunting cannot be considered sustainable anywhere in the region, and in most places enforcement of protected‐area and protected‐species legislation is weak. The international community's focus on cross‐border trade fails to address overexploitation of wildlife because hunting and the sale of wild meat is largely a local issue and most of the harvest is consumed in villages, rural towns, and nearby cities. In addition to improved enforcement, efforts to engage hunters and manage wildlife populations through sustainable hunting practices are urgently needed. Unless there is a step change in efforts to reduce wildlife exploitation to sustainable levels, the region will likely lose most of its iconic species, and many others besides, within the next few years.     

Comparison of methods for the analysis of dissolved urea in seawater

A comparison between the diacetyl monoxime and urease methods for measuring dissolved concentrations of urea in seawater was conducted in artificial seawater, phytoplankton-culture filtrate and both natural and ureaspiked field samples from coastal and oceanic enviroments during 1984. The urease technique underestimated urea concentrations in unbuffered photoplankton-culture filtrate as a result of the inhibition of the urease enzyme, causing the incomplete hydrolysis of urea in these samples. Factors responsible for inhibiting urease included pH, seawater ions, and possibly extracellular metabolites produced in unialgal cultures. Seawater type and time of sample collection were important variables affecting urea measurement by the urease method, and recovery of internal standards ranged from 40 to 100%. Increasing the heating time of the urease assay, or the concentration of urease added to the seawater samples increased the amount of urea determined by the urease method. However, measured values were still less than the concentration of the urea internal standards. The diacetyl monoxime method was suitable for urea determinations in all the seawater samples we examined; it was easily automated, and the results were accurate and reproducible. This modified technique is recommended for measuring disolved concentrations of urea in seawater.