Evidence of fish population responses to acidification in the Eastern United States

The hypothesis that acidification has reduced or eliminated fish populations in certain areas of the eastern United States was investigated by examining present and historical fishery survey records. The causes of acidification (e.g., atmospheric deposition) were not specifically considered, although instances of obvious alternative explanations (e.g., acid mine drainage, organic acids) were avoided. The number of usable data sets located was small. Trend analyses are severely limited by the lack of high quality historical data. The strongest evidence for fisheries declines associated with acidification is provided by data for the Adirondack Mountain region of New York. In some lakes, fish populations have declined or disappeared; lakes experiencing fishery declines are now acidic. Alternative explanations for changes in fish communities over time were examined. In 49 lakes, some or all fish populations have apparently been lost with no available explanation other than acidification. Extrapolation of these data to the entire Adirondack Mountain region suggests that perhaps 200 to 400 lakes may have lost fish populations as a result of acidification. Streams in Pennsylvania and Massachusetts also had documented declines in fish populations that were associated with acidity; however, the data are fewer and less complete than those for New York. Acidification effects on fishery resources in other regions of the eastern United States are apparently minimal. The extent of the damage to date appears small relative to the total resource.     

The role of organic acids in the acidification of surface waters in the Eastern U.S.

There is considerable uncertainty concerning the role of naturally occurring organic solutes in the acidification of surface waters. To provide a preliminary assessment of this process, we evaluated water chemistry data obtained from the US EPA Eastern Lake Survey (ELS). A wide range of dissolved organic carbon (DOC) and organic anion concentrations were evident across acid-sensitive lake districts in the Eastern US. In particular, lakes in Maine, the Upper Midwest and Florida contained high concentrations (greater than 1000 gmol C · L^?1) of DOC. High concentrations of organic anions, estimated by discrepancy in charge balance in several subregions, suggest that dissociation of naturally occurring organic acids could significantly reduce the ANC of dilute surface waters. Unfortunately, analysis of acidification by organic solutes is complicated by uncertainty in H⁺ dissociation characteristics. Input of organic acids with weakly acidic pK _a values do not alter acid neutralizing capacity (ANC), while strongly acidic organic functional groups dissociate completely and decrease ANC. As a first step to assess the acid/base characteristics of naturally occurring organic solutes, we calibrated the Oliver et al. (1983) model, using a reduced version of the ELS data set. This model explained 94% of the observed variability in organic anion concentration in this data set. However, model parameters obtained from the ELS calibration were somewhat different than values provided by Oliver et al. (1983), based on potentiometric titrations of pre-concentrated organic acids. The discrepancy in model parameters has implications for estimating organic anion concentrations in water using the Oliver et al. (1983) model. Finally, data from the ELS indicates that across glaciated regions of the eastern US, concentrations of DOC and organic ions were negatively correlated with SO _inf2? ^p4 . This trend would appear to be consistent with the hypothesis that inputs of strong acids immobilize organic acids, resulting in a shift of surface water acidification by organic acids to strong acids.     

Regional chemical characteristics of lakes in North America Part II: Eastern United States

A survey of 1592 lakes ( >4 ha and ≤ 2,000 ha) was conducted in Fall, 1984. The study area was three regions of the eastern United States (Northeast, Upper Midwest, and Southeast) expected to contain the most lakes with acid neutralizing capacity (ANC) ≤400 μeq/L. The design of the survey provides statistically reliable estimates of the number, location and chemical characteristics of lakes in the study area. Frequency distribution statistics are presented for pH, ANC, sulfate and organic anion. The highest percentages and numbers of acidic lakes occurred in Florida, the Adirondaks, and the Upper Peninsula of Michigan. The highest percentages and numbers of lakes with high sulfate concentrations occurred in the Poconos/Catskills, Southern New England and Florida. The highest percentages and numbers of lakes with high organic anion concentrations occurred in Northeastern Minnesota, the Upper Great Lakes Area and Florida. The percentage of acidic lakes by sulfate concentration class revealed no discernable pattern across subregions. In contrast, the acidic lakes occur with the highest frequency in the lowest organic anion concentration class. The complex distribution of low ANC lakes cannot be explained simply by sulfate concentrations or organic acids.     

Inter-regional comparison of patterns and trends in surface water acidification across the United States

Temporal trends in acid-base chemistry are reported for surface waters in 6 regions of the United States. The lakes and streams are low ANC, dilute systems, selected to represent acid-sensitive aquatic resources in the 6 regions. The predominant trends observed were decreases in lake and stream SO₄ ^2? concentrations in sites east of the Mississippi River, and increases in NO₃ ^? in the Adirondack lake and Catskill stream sites (both located in eastern New York State). Correlations of trend results from all sites with other factors indicated that trends in precipitation volume were highly correlated with the observed trend patterns. From the surface water trend results, three distinct clusters were identified that corresponded to three trend patterns: ‘dilution,’ ‘recovery,’ and ‘acidification.’ These were distributed across the LTM regions, with no particular geographic patterns.     

Frequency distributions for durations and volumes of rainfalls in the Eastern United States in relation to acidic precipitation

A significant percentage (between 17 and 40%) of all showers recorded on Long Island, NY, Urbana, IL, Franklin, NC, and Seaside Park, NJ, had durations less than 20 min. Similarly, a large percentage had durations less than 40 min (50, 46, and 32% for 3 yr at Urbana, IL, 65% at Coral Gables, FL, 50% at Franklin, NC, and 54% at Seaside Park, NJ). When all data from the six growing seasons were pooled, over 88% of all rainfalls were less than 160 min. Similar results were observed when volume measurements were made. Between 38 and 57% of all recorded showers had less than 1 mm at all five stations in the eastern United States. When all data were pooled, over 65% of all rainfalls were less than 3 mm. These data demonstrate that plant foliage is wetted during the growing season by numerous showers which are of short duration and low volume.     

Effect of several production factors on two varieties of rapeseed in the central United States

Two varieties of winter rapeseed (Brassica napus) (Cobra and Liborius) were planted at Brownstown, IL to evaluate the effect of planting date, nitrogen (N) rate, N application timing, and tillage on grain yield and oil content of the grain, grain moisture, plant lodging, winter survival, and plant N content. Results indicated that planting rapeseed approximately one to two weeks prior to winter wheat in this region is preferable to planting earlier. Grain yield showed a significant linear increase with delayed planting date from 25 August to 24 September. Grain yield also increased quadratically with increasing N rate (with an optimum of about 250 kg N/ha) and increased (0.15 Mg/ha) due to splitting the N fertilizer into two even applications. An increase in grain yield was accompanied by an increase in grain moisture with Liborius (late maturing) having significantly greater grain moisture than Cobra. Winter survival increased linearly with delayed planting date but, was accompanied by a significant quadratic increase in plant lodging. Chisel, as compared to disk tillage, increased plant lodging slightly, but decreased winter survival slightly. Neither delayed planting, N rate, nor splitting of spring N affected oil content. Liborius produced significantly more oil than did Cobra.     

Agricultural Composting in the United States

In the United States, more farms are composting than municipalities, commercial/institutional establishments, and other private sector groups combined. To obtain an overview of agricultural composting in the United States, industry, government, and university representatives from the top 10 beef and dairy cattle, poultry, and swine producing states were contacted between January and April of 1995. These states represent at least 70 percent of the nation's production of these commodities (except for beef cattle at 52 percent). The representatives provided information about the number of farms composting, the materials composted, composting methods, how the compost is used, and motivating and impeding factors for farms to compost. In addition, information was gathered concerning composting crop residues. In this case, specific applications of crop residue composting were identified and individuals knowledgeable about the applications were contacted for background information.

Note the estimated numbers of composting operations presented here represent a best attempt to quantify the composting activity taking place on various types of farms. In many cases, the numbers are rough estimates, based on the assessments of the representatives contacted in each state. Also, they only include the composting operations in the top 10 producing states. A considerable amount of composting occurs outside of these states. Therefore, Tables 1 and 2 underestimate the number of farms that compost.     

Conservation of Lepidoptera in the United States

The need to conserve United States populations of Lepidoptera has been recognised for a century, but intensive programmes to do so have only recently come into being. The evolution of the butterfly and moth conservation movement in the United States is followed from the earliest instances to the present state of progress. The origin and growth of the Xerces Society as the chief body for terrestrial arthropod conservation in America are described. Currently, ecological research and political action aimed at specific lepidopteran protection issues are under way. Several of these are examined and the most acute needs for further study and action indicated. Habitat alteration emerges dramatically as the chief problem in the decline of butterfly and moth populations. The relative importance of pesticides and overcollecting is discussed and reinforces the conclusion that the habitat is paramount. Introductions of organisms for purposes of conservation likewise receive consideration, showing this strategy to be problematical and subject to careful review prior to its use. The various levels of government as well as private bodies and individuals have distinct roles in insect conservation. Greater public awareness of beneficial insects must precede optimal effectiveness of conservation schemes. The appointment of an official federal insect conservator is announced along with his initial proposal for endangered species listings for certain North American butterflies. The prognosis for a national programme is suggested. Lepidoptera conservation in the United States has become a fully fledged movement with numerous successes and with many difficult problems to face. The situation is viewed with immediate alarm but cautious long-term optimism as well.     

A paradox of cooling winter soil surface temperatures in a warming northeastern United States

Climate model projections indicate that wintertime temperatures will warm and change snowfall patterns in the northeastern U.S. Snow provides insulation for soils from air temperature fluctuations. Therefore, these snowfall changes will have consequences, particularly for soil surface temperatures. Changes in minimum soil surface temperatures were investigated using a heat flow soil temperature model, driven using daily average air temperature and snow depth data. Two scenarios of three coupled atmosphere-ocean circulation models were used to run the soil temperature model. Modeled projections of minimum soil surface temperatures in the northeastern U.S. indicate that warming will occur over the majority of the region over the 2000-2099 period. In contrast, soil surface temperature projections in the northernmost and snowiest regions of the Northeast indicate minimum soil surface temperatures will be colder. In these northern regions, the coldest soil surface temperatures are also projected to occur later in winter, but show little change in other regions. Most trends throughout the Northeast are enhanced using the higher emission scenario A1fi. Changes to snow depth drive the changes in the minimum soil surface temperatures where snow persists during winter, whereas average air temperatures drive changes in the rest of the northeastern U.S.     

Acidity status of surface waters in Massachusetts

The Massachusetts Acid Rain Monitoring project surveyed 80.5% of the state's 5294 named water bodies between 1983 and 1985. PH and acid neutralizing capacity (ANC) were measured monthly the first 14 mo and semi-annually afterwards. Sample collection and analysis were performed by volunteers. The majority of surface waters in Massachusetts were found to be sensitive to possible long term acidification, with 63% exhibiting ANC less than 200 μeq L^?1 and 22% with ANC less than 40 μeq L^?1. Seasonal patterns in ANC were observed, the median ANC being 384 μeq L^?1 in summer/fall and 134 μeq L^?1 in winter/spring. Geographical differences were also found across the state: the streams and lakes with lowest pH and ANC were located in the southeastern and north-central parts of the state, while the most alkaline surface waters were found in the western-most part of the state, which is the only area of the state with significant limestone deposits.     

Operational liming of surface waters in Sweden

From 1977 to 1982, liming of acidified waters was performed for a trial period using governmental subsidies. Based on the experience gained, an operational liming program was started in 1982 by the National Environmental Protection Board of Sweden. All waters with pH of less than 6 and/or an alkalinity of less than 0.05 meq L^?1 have been eligible for subsidies. Individual water owners as well as organizations and federal agencies may apply for subsidies. Normally 85% of the costs are covered by government grants. Each county administration draws up a 5 yr liming plan and applies yearly for subsidies on a county basis. Since 1977, SEK (Swedish Kroner) 373 million have been spent on liming operations and SEK 33 million on administration and follow-up studies. A yearly budget of about SEK 110 to 130 million has been proposed for 1988 to 1991. The liming agent used has been powdered CaCO₃ with a particle size normally of 0 to 0.2 mm. At present, about 4,000 lakes have been treated. The results of the treatments are normally evaluated by analyzing water samples taken twice a year. These are analyzed for pH, alkalinity, conductivity, color, Ca and Mg. In addition, biological surveys are carried out in selected lakes and streams.     

Impacts of mercury contamination in the southeastern United States

Mercury (Hg) contamination from a variety of point and non-point sources, including atmospheric inputs, is currently considered to be the most serious environmental threat to the well being of fish and wildlife resources in the southeastern United States. Fish consumption advisories have been issued in all ten states comprising the U.S. Fish and Wildlife Service's Southeast Region. Both freshwater and marine species have been affected with levels ranging as high as 7.0 ppm in some individuals. Many other species, including various species of reptiles, birds and mammals (including humans) are also contaminated. Impacts noted range from reproductive impairment to mortality.     

Mortality and morbidity in agriculture in the United States

This article summarizes the trends in agricultural injuries and illnesses in the past decade, as well as the needs for surveillance in the future. Agriculture is one of the most hazardous industries in the U.S. The fatality rate in agriculture remained high (about 22/100,000 workers) through the 1990s. and tractors remained the leading source of death, causing approximately 300 fatalities each year. Non-fatal injuries and illnesses decreased in the employed agricultural worker population. There are no adequate injury and illness data for self-employed farmers and family members to show trends over time. The reported injury rates have been 0.5 to 16.6/100 workers, based on the source of information. Many studies have shown high rates of respiratory and musculoskeletal symptoms, hearing loss, and skin disorders in agriculture. The overall cancer rate is lower; however, certain cancers are elevated in farmers. Surveillance information has not improved significantly in the past decade; however, many studies have provided more insight into the prevalence, incidence, and risk factors for injury and illness. Further efforts are needed to better define the populations at risk, including farmers and ranchers, family members, workers, migrant and seasonal workers, and others exposed to farm hazards. Fatalities are well documented, and it is important to continue existing surveillance in the future. Surveillance systems should be developed to collect information on agriculture-related non-fatal injuries and illnesses.     

Perchlorate in the feed-dairy continuum of the southwestern United States

Perchlorate has the potential to cause thyroid dysfunction by inhibiting iodide uptake by the sodium iodide symporter. Perchlorate-contaminated waters may lead to human exposure through drinking water and food chain transfer in crops by way of irrigation water. Perchlorate has been found in dairy milk collected nationally and internationally. This study was conducted to evaluate perchlorate in the feed-dairy continuum in the southwestern United States. All feed products collected at dairies in this study had detectable levels of perchlorate as analyzed by ion chromatography-tandem mass spectrometry. The calculated total perchlorate intake across dairies ranged from 1.9 to 12.7 mg/cow per day. The variation in total perchlorate intake across dairies was largely associated with variation in forage and silage products. Alfalfa products were the single most important source of perchlorate intake variability among dairies. The estimated perchlorate intake from drinking water ranged from 0.01 mg per cow per day and was generally less than 2% of the total perchlorate intake. The perchlorate content of milk ranged from 0.9 to 10.3 microg/L and was similar to levels reported by the Food and Drug Administration's Total Diet Study. The perchlorate content of milk was significantly related to the presence of perchlorate in feed but the variation of perchlorate in milk could not be explained by feed intake alone.     

Acid rain deposition patterns in the continental United States

Acid rain has become a major environmental concern, the current extent of which is illustrated in this paper. Maps of both pH and H⁺ deposition in precipitation have been developed for the continental United States by analyzing laboratory pH data from nine precipitation chemistry networks and two single stations spread across the continental United States and southern Canada during the late 1970's. Average laboratory pH values were obtained or calculated for approximately 100 stations, and isopleths of weighted mean pH and mean annual H+ deposition in precipitation were drawn. Results of this analysis show that in spite of a wide variety of collection methods and sampling intervals, there is remarkable uniformity in the average pH among the various stations. The northeastern United States continues to exhibit the most acidic precipitation, with remaining portions of the eastern United States, states along the western coastline and a pocket in central Colorado also experiencing acid precipitation.     

Development of Soil Taxonomy in the United States of America

Soil Taxonomy was developed primarily for the practical purpose of supporting the National Cooperative Soil Survey Program in the United States. The previous system of classification was limited in its usefulness and could not be applied consistently by a large cadre of soil scientists with diverse levels of skill and experience. The first edition of Soil Taxonomy, published in 1975, was developed under the leadership of Dr. Guy Smith over a period of about 25 years. The magnitude and complexity of the information favored the use of a hierarchical system presented as a key for consistent application. Operational definitions were used to identify taxonomic limits and diagnostic horizons and features, so that each taxon conveyed the same meaning to every user. The application of Soil Taxonomy had several important impacts on the soil survey program in the United States. The emphasis on objective, measurable diagnostic horizons and features to define classes made all competent soil scientists, regardless of experience and rank, equally capable of accurately and consistently classifying soils. The use of quantitative class differentia improved the quantity and quality of the field data collection. The property ranges of soil series and their geographic distribution have generally been narrowed over time, thus, allowing more precise interpretations to be made. Soil Taxonomy has benefited the soil correlation process by grouping the nearly 22 000 series currently established in the United States in ways that allow us to efficiently compare and differentiate competing soil series and coordinates their use among survey areas. After publication in 1975, Soil Taxonomy was further refined through the work of nine international committees and many individuals. This work culminated in the publication of the second edition in 1999 and, most recently, the 9th edition of the Keys to Soil Taxonomy in 2003. Today, two international committees are considering revisions to the moisture and temperature regimes and improvements to the classification of anthropogenic soils. Published in Russian in Pochvovedenie, 2006, No. 2, pp. 161–167. This article was submitted by the authors in English.     

Factors Affecting the Use of Conservation Tillage in the United States

Conservation tillage was used on nearly 36% of planted hectares in 1996 in the U.S. This level has remained relatively unchanged since 1991. The use of conservation tillage varies by crop and is dependent on site-specific factors including soil sype, topsoil depth, and local climate conditions. A number of economic, demographic, geographic, and policy factors have affected the adsorption of conservation tillage. While it is not possible to quantify exactly the impact of these factors, it is clear that management complexities and profitability are key factors impeding the further adsorption of conservation tillage.     

Corn yields in the United States and sea surface temperature anomalies in the equatorial pacific ocean during the period 1868–1982

The yearly variation of corn yield above or below the trend in the United States is shown to be closely associated with the occurrence of warm sea-surface temperature anomalies in the equatorial Pacific Ocean. Data for the past 115 years indicate that warmer than normal sea-surface temperatures in the equatorial Pacific Ocean are likely to coincide with above average corn yields in the United States. In the period 1868–1982 there have been fifty warm sea-surface temperature years as identified by Quinn et al. (1978). Examination of the yields on a state-by-state basis shows that Illinois has the strongest association and Iowa is second. For the 115-year record, Illinois and Iowa show a statistical level of significance in a chi square test at the 0.1% level. The adjacent states are at a much lower level. For the total U.S. corn yield which includes a much larger region the results are still significant at the 1.0% level. The results of this paper suggest that during the onset of a warm sea-surface temperature event there is a southerly displacement of the storm tracks during the growing season which modifies the climate so as to produce above average growth of the corn crop. It should be emphasized that these two climate anomalies occur concurrently. In fact, the maximum deviation from normal of the sea-surface temperatures occurs in the winter season after the corn crop has grown. Therefore, these results represent a correlation. The timing of the events suggests that the cause lies elsewhere.