Environmental and sustainability indicators and the concept of situational indicators. A systems approach

Through a systems approach indicators are shown to have the nature of variables, adopting different values or states, while other associated terms allude to special meanings assigned to specific values of the indicators. Practical implications are discussed. The concept of situational indicators of sustainability is introduced, representing a non-numerical function of both “pressures” or “driving forces” and “state” variables. A cost-effective multi-tiered approach to situational indicators is proposed. The concept of situational indicators is shown to be a particular case of indicators of systems behavior. A general systems formulation of the problem of sustainability highlights the importance of indicators of systems behavior and the central role of models in their definition.     

The efficacy of a limestone doser to mitigate stream acidification in a Maryland coastal plain stream: Implications for migratory fish species

The objective of this two-year study was to determine the efficacy of an automated limestone slurry doser to neutralize acidic pulses and improve water quality conditions for enhancing survival of early life stages of migratory fish species in a Maryland coastal plain stream. Implications for survival of early life stages of migratory fish species such as yellow perch (Perca flavescens), white perch (Morone americana), blueback herring (Alosa aestivalis) and alewife (Alosa pseudoharengus) are discussed based on the improved chemical conditions in the dosed area of the stream. Despite problems with overdosing in 1991 and failure of the stage transducer to work properly in 1992, the doser was generally effective in neutralizing acidic pulses (pH depressions) in the stream during three major rain events in both years. Chemical conditions (pH and inorganic monomeric aluminum) reported in the non-dosed area during major rainfall events were potentially stressful to both alewife and blueback herring although neither species was reported spawning in the stream during either year. Mitigating the potential impact of acidic conditions on early life stages of important migratory fish species was not sufficient to ensure spawning. It is therefore recommended that habitat improvement measures and well designed fish stocking programs be implemented concurrently with doser operations if the goal is to create optimum spawning conditions for migratory species.     

The need for long-term stream monitoring programs in forest ecosystems of the Pacific Northwest

Concepts, planning and design procedures are examined that are needed in the development of long-term stream monitoring programs in forested regions. A long-term stream monitoring program is viewed as the key component for bringing together management organizations, researchers and decision-makers to improve the management of natural resources. The keystones of such ecosystem monitoring are long-term data records that provide the basis for analysis of environmental assessment objectives, predictions and analysis of outcomes which in-turn can be used to modify and improve future projects. Management organizations that initiate long-term monitoring programs are urged to use monitoring actions and information to facilitate decision-making processes that pertain to conserving and allocating resources for future beneficial uses. Recommendations are provided for careful planning and definition of interactive activities of monitoring programs and that should provide information feedbacks that can be used to evaluate issues pertaining to beneficial uses of resources. Procedural requirements and literature sources are suggested for developing long-term stream monitoring programs. They include reviews of background and historical information to provide precise definitions of long-term objectives, planning considerations and monitoring methods. Examples are given of specific procedures that need to be identified during the planning process. They include the application of management standards to variable conditions encountered within natural ecosystems and the detection of the timing of recovery phases of stream ecosystem development following a disturbance. These procedures are viewed as being essential for improving applications of management standards and perceived thresholds to stream and watershed ecosystems monitoring programs.     

Empowering women. The solution to a global crisis

Norway's Prime Minister Gro Harlem Brundtland holds a medical degree from the University of Oslo and a Master's degree in Public Health from Harvard University. She served as Norway's Minister of the Environment during 1974-79, and was elected to the Norwegian parliament in 1977. Brundtland is currently chairperson of the World Commission on Environment and Development with ten years of experience as a physician and twenty years as a politician. An edited version of her keynote address to the 1994 International Conference on Population and Development is presented. The Minister's experience has taught her that improved life conditions, a greater range of choices, access to unbiased information, and true international solidarity are the signs of human progress. She stresses the need to empower people, educate them, care for their health, and provide them with equal opportunity to achieve economically. Available combined resources need to be used more efficiently through a reformed and better coordinated UN system, policies must be changed, the role and status of women strengthened, safe, comprehensive reproductive health services provided, and measures taken to achieve a balance between population size and sustainable development in keeping with available global resources.     

Genetic population structure of the recently introduced Asian clam,Potamocorbula amurensis,in San Francisco Bay

The genetic population structure of the recently introduced Asian clam, Potamocorbula amurensis, in San Francisco Bay was described using starch gel electrophoresis at eight presumptive loci. Specimens were taken from five environmentally distinct sites located throughout the bay. The population maintains a high degree of genetic variation, with a mean heterozygosity of 0.295, a mean polymorphism of 0.75, and an average of 3.70 alleles per locus. The population is genetically homogeneous, as evidenced from genetic distance values and F-statistics. However, heterogeneity of populations was indicated from a contingency chi-square test. Significant deviations from Hardy-Weinberg equilibrium and heterozygote deficiencies were found at the Lap-1 locus for all populations and at the Lap-2 locus for a single population. High levels of variability could represent a universal characteristic of invading species, the levels of variability in the source population(s), and/or the dynamics of the introduction. Lack of differentiation between subpopulations may be due to the immaturity of the San Francisco Bay population, the general purpose phenotype genetic strategy of the species, high rates of gene flow in the population, and/or the selective neutrality of the loci investigated.     

Immunity in children with exposure to environmental lead: II. Effects on humoral immunity

Lead has been found to depress the immune system in animal studies at levels far below those responsible for overt toxicity. Literature studies in animal systems most clearly showed an effect of lead on response to a specific immunogenic stimulus. Data are sparse concerning the effects of lead on the immune system in the human population at greatest risk for exposure-children up to six years of age. This portion of the Phase I study reports concentrations of IgG, IgM, IgA, and IgE, as well as antibody titers to the specific antigenic stimuli provided by the vaccines against diphtheria, tetanus, and Rubella. The study population consisted of a group of 193 children, ages 9 months to 6 years, who participate in the WIC (Women, Infants and Children) and Lead Poisoning Prevention Programs in the urban area of Springfield-Greene County Missouri. Blood lead levels ranged from 1 to 50 g dL^–1. Total Ig levels were determined and the data were analysed. No consistent significant differences were observed among the risk categories in the five age groups examined. A single Ig class in each of three age groups showed apparent significant differences among the various risk categories, but these differences were not correlated with blood lead. An analysis of specific antibody titers to diphtheria, tetanus, and Rubella was performed. Regression analyses of current data in Phase I of this study suggest a detrimental effect of lead on the antibody titres to diphtheria and Rubella.     

Polycyclic aromatic compounds in Northwest Atlantic COD (Gadus morhua)

Twenty-seven polycyclic aromatic compounds (PAC) including polycyclic aromatic hydrocarbons (PAH) and polycyclic aromatic sulphur heterocycles were analysed in muscle, liver and ovaries of cod (Gadus morhua) from the Northwest Atlantic. These PAC include the 16 PAH priority pollutants (EPA recommendation), alkylated naphthalenes, phenanthrene-anthracenes as well as dibenzothiophenes (DBT). Aromatics were undetectable in muscle. One of the analysed PAC was detected in one ovary and six in another ovary sample. Liver samples contained between 1 and 9 PAC. Of the parental PAH, only acenapthene (18 ng/g, dry weight), fluorene (28 ng/g) and chrysene (22 ng/g) were detected once each in two liver samples, while fluorene (72 ng/g) was detected once in one of the ovaries. C-2 DBT was the major component in ovaries and liver (8-86 ng/g), while C-3 and C-4 alkylated phenanthrene-anthracene (12-78 ng/g) were the next major components detected in the liver samples. This is the first detailed study of PAH and PAC in finfish from the Northwest Atlantic.     

Declines in organochlorines in eggs of red-breasted mergansers from Lake Michigan, 1977–1978 versus 1990

From 1977–1978 to 1990, concentrations of polychlorinated biphenyls (PCBs) and most organochlorine pesticides declined in eggs of red-breasted mergansers (Mergus serrator) nesting on islands in northwestern Lake Michigan. Total PCBs decreased 60% (from 21 ppm in 1977–1978 to 8.5 ppm in 1990) and p,p-DDE decreased 66% (from 6.5 to 2.2 ppm). Dieldrin decreased only 16% (from 0.82 to 0.69 ppm). In 1990, 79.1% of incubated eggs hatched, which was not significantly different from the 83.5% that hatched in 1977–1978.The U.S. Government right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged.     

Comparison of allozyme and mitochondrial DNA spatial differentiation in the limpet Patella vulgata

Allozyme and restriction enzyme analysis of mtDNA was used to study variation in samples from British populations of the marine limpet Patella vulgata in two regions. South Wales and Northeast England. Allozyme analysis revealed significant differences in allele frequencies among samples. However F _ST (population differentiation) values were no higher between than within regions, indicating that genetic heterogeneity was localised and not related to geographic separation. For mtDNA, samples from South Wales exhibited higher haplotype diversity values than samples from Northeast England. In addition there were substantial differences in the haplotype distribution between regions. The value of , the haploid analogoue of F _ST , was low within regions (=0.09) but high between regions (=0.44). The estimated difference in migration rate for allozymes and mtDNA exceed the neutral expectation, unless it is assumed that there are influential differences in the magnitude of female and male gametic dispersal.     

Interactions between copper and cadmium modify metal organ distribution in mature tilapia, Oreochromis mossambicus

Sexually mature female tilapia were exposed to sublethal concentrations of waterborne Cu and/or Cd over 6 days, and subsequent body concentrations of these metals were determined in several organs. The results show that the distribution of Cu and Cd was metal and organ specific. This is demonstrated, for example, by the observation that in tilapia, Cu exposure did not result in Cu accumulation in the liver, whereas in the intestinal wall, notably high concentrations of Cu and Cd were measured in metal exposed fish. In addition to single metal exposed fish, we also determined Cu and Cd body distribution in Cu?Cd co-exposed fish. The observed interactions in metal accumulation were most pronounced in the organs of fish exposed to low, environmentally realistic, metal concentrations.