Showing papers on "Nonpoint source pollution published in 2000"

Assessing Watershed-Scale, Long-Term Hydrologic Impacts of Land-Use Change Using a GIS-NPS Model

Abstract: Land-use change, dominated by an increase in urban/impervious areas, has a significant impact on water resources. This includes impacts on nonpoint source (NPS) pollution, which is the leading cause of degraded water quality in the United States. Traditional hydrologic models focus on estimating peak discharges and NPS pollution from high-magnitude, episodic storms and successfully address short-term, local-scale surface water management issues. However, runoff from small, low-frequency storms dominates long-term hydrologic impacts, and existing hydrologic models are usually of limited use in assessing the long-term impacts of land-use change. A long-term hydrologic impact assessment (L-THIA) model has been developed using the curve number (CN) method. Long-term climatic records are used in combination with soils and land-use information to calculate average annual runoff and NPS pollution at a watershed scale. The model is linked to a geographic information system (GIS) for convenient generation and management of model input and output data, and advanced visualization of model results. The L-THIA/NPS GIS model was applied to the Little Eagle Creek (LEC) watershed near Indianapolis, Indiana, USA. Historical land-use scenarios for 1973, 1984, and 1991 were analyzed to track land-use change in the watershed and to assess impacts on annual average runoff and NPS pollution from the watershed and its five subbasins. For the entire watershed between 1973 and 1991, an 18% increase in urban or impervious areas resulted in an estimated 80% increase in annual average runoff volume and estimated increases of more than 50% in annual average loads for lead, copper, and zinc. Estimated nutrient (nitrogen and phosphorus) loads decreased by 15% mainly because of loss of agricultural areas. The L-THIA/NPS GIS model is a powerful tool for identifying environmentally sensitive areas in terms of NPS pollution potential and for evaluating alternative land use scenarios for NPS pollution management.

Hydrologically sensitive areas: Variable source area hydrology implications for water quality risk assessment

Abstract: A conceptual approach to assessing water quality risk in the context of variable source area hydrology was developed and applied to the New York City (NYC) water supply watersheds. The term hydrologically sensitive area (HSA) was used to refer to areas in a watershed especially prone to generating runoff that are, therefore, potentially susceptible to transporting contaminants to perennial surface water bodies. As an example, a cost benefit method for quantifying HSAs was developed and applied such that water quality protection was balanced with agricultural needs for NYC watersheds. In accordance with the variable source area concept, the spatial extent of HSAs vary throughout the year. On an annual average, approximately 10% of the watershed is designated HSA and about 20% of the total annual runoff originates on these HSAs. This study is meant to illustrate an approach to dealing with water quality risk assessment.

Ability of restored wetlands to reduce nitrogen and phosphorus concentrations in agricultural drainage water

Abstract: Runoff from artificially drained agricultural lands is a common source of excessive nitrogen and phosphorus to downstream waters. Restored wetlands receiving crop field drainage water are shown to lower concentrations of both nitrogen and phosphorus. Case studies in Maryland, Illinois, and Iowa indicate that wetlands can remove up to 68% of nitrate-nitrogen and 43% of phosphorus from drainage water, although performance varies considerably. Performance comparison across sites indicates that large wetlands relative to the contributing drainage area most effectively improve water quality. Time series data representing periods of both relatively high and low inflow indicate that performance is highly sensitive to retention time, with greatest nutrient removal during flow conditions that facilitate retention times of at least one to two weeks. Where wetlands are incorporated into forested riparian buffer strips, additional water quality benefits are shown.

The use of remote sensing and GIS in watershed level analyses of non-point source pollution problems

Abstract: Basin characteristics such as land use/land cover, slope, and soil attributes affect water quality by regulating sediment and chemical concentration. Among these characteristics, land use/land cover can be manipulated to gain improvements in water quality. These land use/land cover types can serve as nutrient detention media or as nutrient transformers as dissolved or suspended nutrients move towards the stream. This study examines a methodology to determine nitrate pollution ‘contributing zones’ within a given basin based on basin characteristics. In this process, land use/land cover types were classified and basins and ‘contributing zones’ were delineated using geographic information system (GIS) and remote sensing (RS) analysis tools. A ‘land use/land cover-nutrient-linkage-model’ was developed which suggests that forests act as a sink, and as the proportion of forest inside a contributing zone increases (or agricultural land decreases), nitrate levels downstream will decrease. In the model, the residential/urban/built-up areas have been identified as strong contributors of nitrate. Other contributors were orchards; and row crops and other agricultural activities.

REMM: The Riparian Ecosystem Management Model

Abstract: Riparian buffer zones are effective in mitigating nonpoint source pollution and have been recommended as a best management practice (BMP). The Riparian Ecosystem Management Model (REMM) has been developed for researchers and natural resource agencies as a modeling tool that can help quantify the water quality benefits of riparian buffers under varying site conditions. Processes simulated in REMM include surface and subsurface hydrology; sediment transport and deposition; carbon, nitrogen, and phosphorus transport, removal, and cycling; and vegetation growth. Management options, such as vegetation type, size of the buffer zone, and biomass harvesting also can be simulated. REMM can be used in conjunction with upland models, empirical data, or estimated loadings to examine scenarios of buffer zone design for a hillslope. Evaluation of REMM simulations with field observations shows generally good agreement between simulated and observed data for groundwater nitrate concentrations and water table depths in a mature riparian forest buffer. Sensitivity analysis showed that changes that influenced the water balance or soil moisture storage affected the streamflow output. Parameter changes that influence either hydrology or rates of nutrient cycling affected total N transport and plant N uptake.

Agricultural Nonpoint Source Pollution : Watershed Management and Hydrology

Abstract: Hydrology Soil Erosion and Sedimentation Nitrogen and Water Quality Phosphorus and Water Quality Impacts Pesticides and Water Quality Impacts Nonpoint Source Pollution and Livestock Manure Management Irrigated Agriculture and Water Quality Impacts Agricultural Drainage and Water Quality Water Quality Models Best Management Practices for Nonpoint Source Pollution Control Monitoring

Nonpoint-source pollutant load reductions associated with livestock exclusion

Abstract: Cattle (Bos taurus) grazing on unimproved pastures can be a significant, yet often overlooked, source of pollutants to surface waters, especially when the cattle have unlimited access to streams in the pastures. Livestock exclusion from streams has been demonstrated to reduce sediment and possibly nutrient yield from streams draining pastures. The purpose of this study was to evaluate the effects of excluding dairy cows from, and planting trees in, a 335-m-long and 10- to 16-m- wide riparian corridor along a small North Carolina stream. Analysis of 81 wk of pre-exclusion and 137 wk of post-exclusion fencing data documented 33, 78, 76, and 82% reductions in weekly nitrate + nitrite, total Kjeldahl nitrogen (TKN), total phosphorus (TP), and sediment loads, respectively, from the 14.9-ha pasture area adjacent to the fenced section of stream. Statistical analyses by t-tests and analysis of variance suggested that the reductions in mean weekly loads post-fencing were significant (P < 0.05) for all pollutants except nitrate + nitrite. Thus, the results indicated that livestock exclusion and subsequent riparian vegetation establishment was effective at reducing pollutant export from an intensively grazed pasture.

Water quality trends and management implications from a five-year study of a eutrophic estuary

Abstract: The Neuse River and Estuary, a major tributary of the second largest estuary on the United States mainland, historically has sustained excessive blooms of algae and toxic dinoflagellates, hypoxia, and fish kills. Previous attempts have been made to use short-term databases of 2–3 years, or data sets from infrequent (monthly) sampling, to assess whether nutrient inputs to the Neuse are increasing and supporting higher algal production. These previous efforts also have relied on single-point-determined flow velocity data, at upstream sites remote from the estuary, to estimate the volume of flow in quantifying nutrient loading to the estuary. We completed a five-year study of the Neuse, including a comparative inventory of nutrients to the watershed from point sources and from concentrated animal operations (CAOs) as recent nonpoint sources, as well as an intensive assessment of water quality over time in the mesohaline estuary. Estimates of nutrient loads were based on volume of flow data from shore-to-shor...

Performance of a Constructed Wetlands in Treating Urban Stormwater Runoff

Abstract: An investigation was conducted on the pollutant removal performance of a constructed wetlands treating stormwater runoff from a residential townhome complex in northern Virginia. Constituent event mean concentrations for 33 runoff events between April 1996 and May 1997 were measured based on flow-weighted composite samples collected at the facility's inlet and outlet. With the results from a limited number of grab samples representing ungauged overland drainage from an adjacent wooded area, estimated removals were positive for most constituents and typically exceeded those obtained at a nearby companion wetland study site, consistent with expectations based on the relative ratios of wetland area to drainage area at the two sites. Median load removals of all constituents were greater for a subset of 22 storms that had inflow volumes less than the maximum volume of the marsh. Orthophosphate phosphorus and ammonia removals were significantly better during spring of 1996 than spring of 1997. Lysimeter data suggest a possible explanation for this, which is development of anaerobic conditions in the shallow sediments in 1997. Outlet concentrations of oxidized nitrogen were consistently lower in base flow than in storm samples, suggesting that removal of this constituent occurred primarily between, rather than during, storm events. Water Environ. Res., 72, 295 (2000).

Salmonella spp. and Fecal Coliform Loads in Coastal Waters from a Point vs. Nonpoint Source of Pollution

Abstract: Coastal areas are often contaminated by the dissemination of pathogenic bacteria from terrestrial inputs. In this study, we compared fecal coliforms (FC) and Salmonella spp.loads from a coastal Mediterranean river and from the submarine outfall of a coastal wastewater treatment station. A stratified sampling strategy was used to analyze storm events. Bacterial fluxes were estimated during a 16-mo period. Salmonella spp. loads from the river were high during storm events, and the annual loads were higher than those estimated from the coastal outfall. Bacterial loads from the river represented 3.0 × 10 16 FC yr -1 and 6.9 × 10 12 Salmonella yr -1 with at least 95% occurring during high waterflow (21% of the year). Those from the submarine outfall represented 4.3 × 10 16 FC yr -1 and 4.7 × 10 10 Salmonella yr -1 , with a regular temporal discharge. Bacterial loads from the river were associated with small clay particles (<2 μm), which originate from different reservoirs. These particles-sediment-trapped bacteria accumulated in the river-bed during the lowest water levels in the downstream part of the river and were resuspended during storm events. The quantitative relationship between both bacterial parameters vary depending on the source point of contamination. Salmonella spp.loads from the river are of great sanitary concern since high loads were recorded in summer (bathing activities) and autumn (oyster production and consumption). Our results should help water quality managers to define priorities to improve the bacterial quality of river discharges.

Export coefficient modeling to assess phosphorus loading in an urban watershed.

Abstract: An export coefficient modeling approach was used to assess the influence of land use on phosphorus loading to a Southern Ontario stream. A model was constructed for the 1995–1996 water year and calibrated within ± 3 percent of the observed mean concentration of total phosphorus. It was found that runoff from urban areas contributed most to the loading of phosphorus to the stream. When the model was assessed by running it for the 1977–1978 water year, using water quality and land use data collected independently, agreement within ± 7 percent was obtained. The model was then used to forecast the impact of future urban development proposed for the watershed, in terms of phosphorus loading, and to evaluate the reduction in loading resulting from several urban best management practices (BMP). It was determined that phosphorus removal will have to be applied to all the urban runoff from the watershed to appreciably reduce stream phosphorus concentration. Of the BMP designs assessed, an infiltration pond system resulted in the greatest phosphorus load reduction, 50 percent from the 1995–1996 baseline.

SPECIAL ISSUE THE VALUES OF WETLANDS: LANDSCAPE AND INSTITUTIONAL PERSPECTIVES Economic criteria for using wetlands as nitrogen sinks under uncertainty

Abstract: If the environmental damages that are caused by excessive nitrogen load to the sea depend on the timing of emissions, then monitoring the stochastic variation of emissions is crucial for controlling eutrophication damages. A significant problem of nonpoint source (NPS) nitrogen pollution is that emissions are stochastic and difficult to control. The main purpose of this paper is to examine under what criteria wetlands are economically rational to use for controlling stochastic NPS pollution. Three criteria are identified using a simplified stochastic watershed model. It is suggested that wetlands are economically rational to use, especially when monitoring the uncertainty of emissions is a part of the decision problem. The theoretical findings are illustrated with an example from southwestern Sweden. © 2000 Elsevier Science B.V. All rights reserved.

Runoff nutrient and fecal coliform content from cattle manure application to fescue plots.

Abstract: Grazed pastures represent a potential source of non-point pollution. In comparison to other nonpoint sources (e.g., row-cropped lands), relatively little information exists regarding possible magnitudes of pollution from grazed pasture; how that pollution is affected by weather, soil, management and other variables; and how the pollution can be minimized. The objective of this study was to assess how the quality of runoff from fescue plots is influenced by duration of cattle manure application (4–12 weeks) and manure application strategy (none, weekly application of 1.4 kg/plot, and monthly application at 5.6 kg/plot). Additional analyses were performed to relate runoff quality to the timing of sample collection. The study was conducted at the University of Kentucky Maine Chance Agricultural Experiment Station north of Lexington. Plots (2.4 m wide by 6.1 m long) were constructed and established in Kentucky 31 fescue (Festuca arundinacea Schreb.) to represent pasture. Grazing was simulated by application of beef cattle manure to the plots. Runoff was generated by applying simulated rainfall approximately 4, S and 12 weeks following initiation of manure application. Runoff samples were collected and analyzed according to standard methods for nitrogen (N), phosphorus (P) and fecal coliforms (FC). Runoff concentrations of N and P from manure-treated plots were low and generally not consistently different from control plot concentrations or related to manure application strategy. Runoff FC concentrations from manure-treated plots were higher than from control plot concentrations. Runoff concentrations of ammonia N, total Kjeldahl N, ortho-P and FC decreased approximately exponentially in response to increasing time of sample collection. These findings suggest that manure deposition on well-managed pasture at the rates used in this study might have a negligible impact on nutrient content of runoff.

Phosphorus Flow in a Watershed-Lake Ecosystem

Abstract: Cultural eutrophication of lakes caused by excess phosphorus (P) loading from agricultural areas is a persistent and serious environmental problem. We quantified P flows in a watershed-lake ecosystem using a simple mathematical model that coupled in-lake and upland processes to assess and compare the long-term impacts of various management strategies. Our model compares abatement by in-lake strategies (such as increasing the flux of P from algae to consumers and alum application) with riparian management to decrease P flow and with balancing P budgets at the watershed scale. All of these strategies are effective to some extent. However, only reducing the amount of fertilizer P imported to the watershed will decrease the total P in the system at steady state. Soil P—a large reservoir with slow turnover rate—governs long-term flux to the lake and must be decreased in size to maintain long-term control of eutrophication.

Erosion Control at Construction Sites: The Science–Policy Gap

Abstract: To test the effectiveness of Michigan's soil ero- sion control law, 30 construction sites were evaluated in the east-central part of the state. The analytical framework lumped nine best management practices (BMPs) most closely related to the law into three categories: slope stabili- zation, soil stabilization, and water management. All sites were in the land clearing or foundation/framing stage of con- struction and were evaluated within 2 days after a rainfall event. Only four of the sites performed above the mean of the scoring scale, with the categorical scoring of BMPs indi- cating the worst performance for slope stabilization mea- sures. The poor results suggest a failure to integrate scien- tific knowledge of erosion control with policy. A fundamental problem is the lack of basic site data on soil, topography, and hydrology, resulting in the incorrect application of BMPs, such as staging, filter fences, and berms. The current institu- tional framework for soil erosion control also provides disin- centives to mitigate local erosion problems. Soil erosion and stream sedimentation are persistent problems in and around construction sites. Though minor compared to cropland in terms of total sediment yield for the United States as a whole, individual construc- tion sites can contribute massive loads of sediment to small areas in short time periods. Although soil loss rates have generally declined in most construction areas since Wolman and Schick (1967) reported loss rates over 100,000 tons/mi 2 /year, many modern construc- tion sites suffer substantial loss rates despite regulation. The effects of soil erosion and sedimentation on streams, lakes, and wetlands are well documented (Graf 1975, Booth 1990). These impacts are expensive in terms of dollar costs and aesthetic costs (Pimentel and others 1995). Sediment is widely considered the princi- pal pollutant in our water systems, a point explicitly recognized in the Clean Water Acts (CWAs) enacted in 1972 and the Food Security Act of 1985. The Food Security Act established a Conservation Reserve Pro- gram, providing an opportunity for farmers to enter into 10-year contracts with the Department of Agricul- ture to take highly erodible land out of production and receive annual rental payments for returning the land to permanent vegetative cover. In the 1987 reauthorization of the CWA all states were required to conduct an assessment of nonpoint sources and develop mitigation strategies. The state of Michigan responded quickly and in 1987 conducted an assessment of nonpoint sources. In 1988, a mitigation plan was developed, which promoted the identification of nonpoint pollution sources at the watershed level, and the implementation of best management practices (BMPs) (MDNR 1988). BMPs are structural, vegetative, or managerial practices used to treat, prevent, or reduce water pollution. In 1992, a revised version of the 1987 BMP list was prepared with yearly updates (MDEQ 1992). Erosion control procedures in Michigan are gov-

Cross-Media Models of the Chesapeake Bay Watershed and Airshed

Abstract: A continuous, deterministic watershed model of the Chesapeake Bay watershed, linked to an atmospheric deposition model is used to examine nutrient loads to the Chesapeake Bay under different management scenarios. The Hydrologic Simulation Program - Fortran, Version 11 simulation code is used at an hourly time-step for ten years of simulation in the watershed. The Regional Acid Deposition Model simulates management options in reducing atmospheric deposition of nitrogen. Nutrient loads are summed over daily periods and used for loading a simulation of the Chesapeake estuary employing the Chesapeake Bay Estuary Model Package. Averaged over the ten-year simulation, loads are compared for scenarios under 1985 conditions, forecasted conditions in the year 2000, and estimated conditions under a limit of technology scenario. Limit of technology loads are a 50%, 64%, and 42% reduction from the 1985 loads in total nitrogen, total phosphorus, and total suspended solids, respectively. Urban loads, which include point source, on-site wastewater disposal systems, combined sewer overflows, and nonpoint source loads have the highest flux of nutrient loads to the Chesapeake, followed by crop land uses.

Economic and Environmental Impacts of Alternative Practices on Dairy Farms in an Agricultural Watershed

Abstract: Nutrient losses from agricultural nonpoint sources are a key component of surface water impairment across the United States. Nitrogen is clearly the primary pollutant problem in many agricultural areas. However, development of management practices that reduce phosphorus loadings is becoming more important in many watersheds because phosphorus is often the limiting nutrient for fresh water eutrophication. This study presents the results of computer simulations performed to assess the impacts of various management practices on phosphorus losses from dairy farms in a watershed in north central Texas. The results show that moving from nitrogen to phosphorus-based waste application rates could significantly reduce phosphorus losses at moderate cost to producers. Composting solid manure for end uses outside the impacted watersheds provides even greater phosphorus load reductions and requires less land, but results in significantly higher cost to producers. The choice for each watershed depends on such key factors as available land area and the load reduction sought.

Integration of a Nonpoint Source Pollution Model with a Decision Support System

Abstract: This paper is a progress report of an ongoing research project from which the expected final product will be an integral system to model nonpoint source pollution in surface waters. Diffuse pollution models will be included in a decision support system with a unique platform, common interfaces and GIS capabilities. This system will accommodate pre- and postprocessing tools, model control and sensitivity analysis for the parameters in the models. Particularly, the construction of the interface for the AGNPS model and its link with the decision support system RAISON is presented. The model is described, including the input requirements, the development of tools and the procedures created to extract the necessary data from digital elevation model, soil type and landcover vectorized files.

Standard Handbook of Environmental Science, Health, and Technology

Abstract: Part I: The Interaction of Basic Scientific Disciplines on Contaminant Fate and Transport in the Environment. Chapter 1: Chemistry. Aquatic Chemistry Environmental Chemistry of the Atmosphere Soil Environmental Chemistry Environmental Biochemistry Toxicological Chemistry Geochemistry Chapter 2: Classes of Chemicals. Hydrocarbons Pesticides and Polychlorinated Biphenyls Chlorinated Solvents Radionuclides Chapter 3: Geology. Geologic Principles Chapter 4: Hydrology. The Hydrologic Cycle Precipitation and Runoff Streamflow and Flood Control Groundwater Flow Well Hydraulics Real-Time Soil Water Dynamics Fate and Transport Modeling - Effectively Using Isotopes of Wtaer to SOlve Practical Hydrogeological Problems Fate and Transport in Fractured Rock Chapter 5: Physical Transport. Air Pollutants and Fugitive Dust Mixing and Transport of Pollutants in Surface Water Chapter 6: Biology. Biology Chapter 7: Contaminant Effects. Toxicity Testing Ecological Risk Assessment Ecological Effects of Toxicants Air Pollutant Sources and Effects Chapter 8: Analysis and Modeling. Geochemical Modeling Groundwater Flow Modeling Solute Transport Modeling Fate and Transport in Rivers, Lakes, and Estuaries Geostatistics Pharmacokinetic/Dynamic Modeling Appendix A: Selected Computer Codes, Software Description and Availability Appendix B: Software for Compartmental Models Appendix C: Computer Codes Geographic Information Systems Computing Optimal Pumping Strategies for Groundwater Contaminant Plume Remediation Appendix A: Formation of Constraint Equations for Repsonse Matrix Models Appendix B: Unique Features of REMAX Economics Part II: Site Based Environmental Science, Health and Technology. Chapter 9: Pollution Prevention Concepts and Policies. Pollution Prevention Science and Technology Plant Operations Urban Stormwater Management and Nonpoint Source Pollution Control Chapter 10: Environmental Regulations. Basics of Environmental Law Chapter 11: Assessment Sampling and Monitoring. Site Evaluation, Auditing, and Assessment Applications of Global Positioning Systems in the Environmental Sciences Indoor Air: Sick and Healthy Buildings Stream Sampling Sediment Collection Monitoring Well Construction and Sampling Techniques Aquifer Testing Soil Vapor Principles Applications and Interpretation of Soil Vapor Data to Volatile Organic Compound Contamination Neutron Probes Direct Sensing of Soils and Groundwater Direct Push Technology Sampling Methods Borehole Geophysics Surface Geophysical Methods for Site Characterization Chapter 12: Toxicology and Risk. Decisions in the Face of Uncertainty Variability and Uncertainty Selecting Indicator and Surrogate Compounds Selecting Indicator Pathways The Dose Makes the Poison: Some Common Misconceptions Low Dose Response-Hormesis Microorganisms, Molecules, and Environmental Risk Assessment: Assumptions and Outcomes Chapter 13: Control Technologies. Hazardous Waste Handling and Disposal Hazardous Waste Dumping as it Relates to a Japanese Risk Management System Medical Waste Incineration Control Technologies: Particulate Controls Control Technologies: Gas Controls Fundamentals of Odor Management Water Supply Treatment A: Design Flow and Loads B: Screens C: Chemical Reactors Water Supply Treatment A: Coagulation, Flocculation, Mixing, and Mixers B: Sedimentation and Filtration Chapter 14: Remediation Technologies. Monitored Natural Attenuation (MNA) Passive In Situ Remediation Technologies Phytoremediation: A Promising Path to the Elimination of Heavy Metals and Radionuclides in Groudwater and Soil Bioremediation of Hazardous Wastes: History and Applications Bioremediation Pump-and-Treat Technologies Electrokinetic Treatment of Hazardous Wastes Surfactant-Enhanced Aquifer Remediation Remediation of Metals-Contaminated Soils and Groundwater DNAPL Investigation and Remediation Vertical Passive Groundwater Barrier Systems Aquifer Restoration via In Situ Air Sparging Chapter 15: Ubiquitous Environmental Contaminants. Endocrine Disruptors Radon in Air Radon and Radon Daughters Chlorofluorocarbons Methyl Bromide Subsurface Petroleum Spills Ionizing Radiation Mortality in Male and Female Capacitor Workers Exposed to Polychlorinated Biphenyls Part III: Place Based Environmental Science, Health and Technology. Chapter 16: Managing Place Scale Problems. Decision Making Ecosystem Management Brownfields Guidelines for Emergency Response Environmental Communication Ecological Engineering Chapter 17: System Level Risk Assessment. Probabilistic Safety in Government and Industry Risk Assessment in the Broader Context Risk Management in View of Economic Aspects Weighing the Risks of Remediation Chapter 18: Environmental Science in the Legal System. Environmental Science, Toxic Torts, and the Legal System Chapter 19: Sensitive Environmental Systems. Karst Systems Alpine Lakes Wetlands Plants and Population: We Have the Time. Do They Have the Will? Chapter 20: Sensitive Environmental Problems. Agricultural Runoff Test of the Validity of the Linear-No Threshold Theory of Radiation Carcinogenesis with a Survey of Radon Levels in U.S. Homes Acid Rain-The Whole Story to Date The Ozone Layer Greenhouse Warming (GHW) Controversies Surrounding the Endangered Species Chapter 21: Misconceptions About Environmental Pollution. Misconceptions about Pollution, Pesticides, and the Prevention of Cancer Science, Pesticides, and Politics Simple Truths of Environmental Facts and Fallacies Chapter 22: Global Perspectives and Trends. The Road from Rio to Kyoto: How Climate Science Was Distorted to Support Ideological Objectives Natural Forces versus Anthropogenic Change Controlling Hazardous Pollutants in a Developing Context: The Case of Arsenic in Chile Emerging Environmental Issues from the Perspective of Industry