EFFECTS OF WATERSHED BEST MANAGEMENT PRACTICES ON HABITAT AND FISH IN WISCONSIN STREAMS1

ABSTRACT: We evaluated the effectiveness of watershed‐scale implementations of best‐management practices (BMPs) for improving habitat and fish attributes in two coldwater stream systems in Wisconsin. We sampled physical habitat, water temperature, and fish communities in multiple paired treatment and reference streams before and after upland (barnyard runoff controls, manure storage, contour plowing, reduced tillage) and riparian (stream bank fencing, sloping, limited rip‐rapping) BMP installation in the treatment subwatersheds. In Spring Creek, BMPs significantly improved overall stream habitat quality, bank stability, instream cover for fish, abundance of cool‐ and coldwater fishes, and abundance of all fishes. Improvements were most pronounced at sites with riparian BMPs. Water temperatures were consistently cold enough to support coldwater fishes such as trout (Salmonidae) and sculpins (Cottidae) even before BMP installation. We observed the first‐time occurrence of naturally reproduced brown trout (Salmo trutta) in Spring Creek, indicating that the stream condition had been improved to be able to partially sustain a trout population. In Eagle Creek and its tributary Joos Creek, limited riparian BMPs led to localized gains in overall habitat quality, bank stability, and water depth. However, because few upland BMPs were installed in the subwatershed there were no improvements in water temperature or the quality of the fish community. Temperatures remained marginal for coldwater fish throughout the study. Our results demonstrate that riparian BMPs can improve habitat conditions in Wisconsin streams, but cannot restore coldwater fish communities if there is insufficient upland BMP implementation. Our approach of studying multiple paired treatment and reference streams before and after BMP implementation proved effective in detecting the response of stream ecosystems to watershed management activities.     

ECOLOGICAL MANAGEMENT PROBLEMS CAUSED BY HEATED WASTE WATER DISCHARGE INTO THE AQUATIC ENVIRONMENT1

Discharge of heated waste water may affect the entire aquatic ecosystem–the interrelated biological, chemical, physical system–and, if the temperature change is large, may destroy the capacity of the ecosystem to serve a variety of beneficial purposes. However, it is possible to discharge heated waste water in carefully controlled amounts without seriously degrading the aquatic ecosystem. There are four basic alternatives which are open to us with regard to the heated waste water problem which we may choose singly or in various combinations: (1) Placing all heated, waste water in streams, lakes, and oceans without regard to the effects. Thus considering the environmental damage as a necessary consequence of our increased power demand. (2) Using, but not abusing, existing ecosystems. This means regulating the heated waste water discharge to fit the receiving capacity of the ecosystem. (3) Finding alternative ways to dissipate or beneficially use waste heat. (4) Modifying ecosystems to fit the new temperature conditions. We are all dependent upon a life-support system which is partly industrial and partly ecological. Unfortunately, we have reached a stage of development where the non-expandable, ecological portion of our life-support system is endangered by the expanding industrial portion. Optimal function and full beneficial use of both portions of our life-support system will only be possible if a variety of disciplines and diverse points of view can cooperate and work together effectively. Since wastes in amounts that are acceptable taken one at a time may be lethal collectively, environmental management should be on a regional basis.     

Sustainable Development in Small Island Developing States

This paper explores the status of sustainable development in small island developing states (SIDS), through the presentation of a case study on the Maldives, which is a typical small island developing state in the Central Indian Ocean. At the outset, a brief history of sustainable development as related to SIDS on the international agenda is outlined, starting from Rio to Barbados to Johannesburg. SIDS are expected to face many challenges and constraints in pursuing sustainable development due to their ecological fragility and economic vulnerability. It is the position of this paper that issues related to environmental vulnerability are of the greatest concern. A healthy environment is the basis of all life-support systems, including that of human well-being and socio-economic development. Priority environmental problems are: climate change and sea-level rise, threats to biodiversity, threats to freshwater resources, degradation of coastal environments, pollution, energy and tourism. Among these, climate change and its associated impacts are expected to pose the greatest threat to the environment and therefore to sustainable development. For small islands dependent on fragile marine ecosystems, in particular on coral reefs, for their livelihoods and living space, adverse effects of climate change such as increased frequency of extreme weather events and sea-level rise will exacerbate the challenges they already face. It is concluded that the paper path from Rio to Barbados to Johannesburg has made significant progress. However, much remains to be done at the practical level, particularly by the developed countries in terms of new and additional efforts at financial and technical assistance, to make sustainable development a reality for SIDS.     

Developing a Standardized Water Quality Index for Evaluating Surface Water Quality1

Abstract: There is a significant need for a science‐based approach to interpret water‐monitoring data and to facilitate the rapid transfer of information to water resource managers and the general public. The water quality Index (WQI) is defined as a single numeric score that describes the surface water quality condition at a particular time and location. The objective of this paper is to describe the WQI concept and the approach for developing an ecoregion‐specific standardized WQI that meets the needs described above. The premise of the proposed WQI is based on categorizing scientifically documented aquatic life responses to changes in instream water chemistry. The method uses an aggregated procedure that matches the entire range of standardized probable biological responses to standardized narrative water quality evaluation categories and standardized rank score categories. The calculation of WQI and decision‐making process are performed within an Excel spreadsheet software program. The article includes examples of the proposed WQI applications that could enhance effective water resource management and facilitate timely communication of water quality conditions to water resource managers and the general public.     

A Biological Assessment of Streams in the Eastern United States Using a Predictive Model for Macroinvertebrate Assemblages1

Abstract: A predictive model (RIVPACS‐type) for benthic macroinvertebrates was constructed to assess the biological condition of 1,087 streams sampled throughout the eastern United States from 1993‐2003 as part of the U.S. Geological Survey’s National Water‐Quality Assessment Program. A subset of 338 sites was designated as reference quality, 28 of which were withheld from model calibration and used to independently evaluate model precision and accuracy. The ratio of observed (O) to expected (E) taxa richness was used as a continuous measure of biological condition, and sites with O/E values <0.8 were classified as biologically degraded. Spatiotemporal variability of O/E values was evaluated with repeated annual and within‐site samples at reference sites. Values of O/E were regressed on a measure of urbanization in three regions and compared among streams in different land‐use settings. The model accurately predicted the expected taxa at validation sites with high precision (SD = 0.11). Within‐site spatial variability in O/E values was much larger than annual and among‐site variation at reference sites and was likely caused by environmental differences among sampled reaches. Values of O/E were significantly correlated with basin road density in the Boston, Massachusetts (p < 0.001), Birmingham, Alabama (p = 0.002), and Green Bay, Wisconsin (p = 0.034) metropolitan areas, but the strength of the relations varied among regions. Urban streams were more depleted of taxa than streams in other land‐use settings, but larger networks of riparian forest appeared to mediate biological degradation. Taxa that occurred less frequently than predicted by the model were those known to be generally intolerant of a variety of anthropogenic stressors.     

ACUTE RESIDUAL TOXICITY OF SEVERAL DISINFECTANTS IN DOMESTIC AND INDUSTRIAL WASTE WATER1

ABSTRACT: This study determined the acute toxicity of waste water disinfected with chlorine, bromine chloride, or ozone. The residual toxicity of effluent dechlorinated with sulfur dioxide was also tested. Toxicity tests were conducted with cyprinid, salmonid, and centrarchid fishes, as well as several species of fresh water macroinvertebrates. Residual chlorine exhibited the greatest toxicity of the disinfectants tested; dechlorination with sulfur dioxide effectively eliminated the toxicity of chlorinated effluent. Residual ozone produced mortality in test animals only under special conditions where subjects were exposed to effluent immediately after it was contacted with ozone, and chlorobrominated effluent was more toxic to salmonids than chlorinated effluent.     

METABOLIC RESPONSES OF AQUATIC BACTERIAL POPULATIONS TO SELECTED INSECTICIDES1

ABSTRACT: Indigenous bacterial populations from a fresh water reservoir were treated by adding five mg/1 Sevin or Malathion to the water at 23, 28, and 33 C. The degradation of Sevin was evidenced by the increased uptake of O₂ as measured by Warburg manometry. The principal degradation product of Sevin, 1-naphthol, appeared to stimulate metabolic activity of these populations to the same extent as the parent compound. The addition of Malathion to this system appeared, on the other hand, to suppress metabolic activity to some degree. Warburg manometry was shown to be a useful, rapid method for detecting effects of insecticides on aquatic microbial populations.     

CHANNELIZATION AND INVERTEBRATE DRIFT IN SOME IOWA STREAMS1

ABSTRACT: Habitat diversity and invertebrate drift were studied in a group of natural and channelized tributaries of the upper Des Moines River during 1974 and 1975. Channelized streams in this region had lower sinuosity index values than natural channel segments. There were significant (P=O.05) positive correlations between channel sinuosity and the variability of water depth and current velocity. Invertebrate drift density, expressed as biomass and total numbers, also was correlated with channel sinuosity. Channelization has decreased habitat variability and invertebrate drift density in streams of the upper Des Moines River Basin and probably has reduced the quantity of water stored in streams during periods of low flow.     

Energy analysis and the coupling of man and estuaries

New concepts and insights concerning human and natural systems in the coastal zone are emerging from recent energy analysis and synthesis studies. By using new concepts for measuring the quality of energy, one can express the work of ecosystems and human economies in equivalent terms. From energy models and new energy quality evaluations, one can learn what kinds of coastal systems maximize power, are competitive, economically vital, and likely to have a survival advantage.Energy analysis and synthesis is aided by energy circuit diagrams. Models of the coastal zone that emphasize the change in external driving functions related to world energy sources provide insights and some predictive abilities that are not found in economic studies, since money flows alone do not evaluate external driving energies.This paper suggests four procedures for coastal planning: 1) calculation of investment ratio in units of equal quality to determine which projects are economic in a broad sense, 2) development of energy signatures for coastal ecosystems, 3) determination of which interface ecosystems develop the best energy flows, and 4) development of regional models that include the main features of human and natural ecosystems.     

Spatiotemporal Associations of Reservoir Nutrient Characteristics and the Invasive,Harmful Alga Prymnesium parvum in West Texas

Golden alga (Prymnesium parvum) is a harmful alga that has caused ecological and economic harm in freshwater and marine systems worldwide. In inland systems of North America, toxic blooms have nearly eliminated fish populations in some systems. Modifying nutrient profiles through alterations to land or water use may be a viable alternative for golden alga control in reservoirs. The main objective of this study was to improve our understanding of the nutrient dynamics that influence golden alga bloom formation and toxicity in west Texas reservoirs. We examined eight sites in the Upper Colorado River basin, Texas: three impacted reservoirs that have experienced repeated golden alga blooms; two reference reservoirs where golden alga is present but nontoxic; and three confluence sites downstream of the impacted and reference sites. Total, inorganic, and organic nitrogen and phosphorus and their ratios were quantified monthly along with golden alga abundance and ichthyotoxicity between December 2010 and July 2011. Blooms persisted for several months at the impacted sites, which were characterized by high organic nitrogen and low inorganic nitrogen. At impacted sites, abundance was positively associated with inorganic phosphorus and bloom termination coincided with increases in inorganic nitrogen and decreases in inorganic phosphorus in late spring. Management of both inorganic and organic forms of nutrients may create conditions in reservoirs unfavorable to golden alga.