Trophic state indexes (TSI) guide management strategies regarding eutrophication control worldwide. Such indexes usually consider chlorophyll-a (Chl-a), total phosphorus (TP), and Secchi disk depth (SDD) as independent variables for estimating aquatic productivity and the degree of impairment. TSIs for each of these components are frequently averaged to produce a single TSI value associated with a trophic state classification (e.g., oligotrophic, mesotrophic, or eutrophic). The potential divergence among equations and classification systems originally developed for temperate lakes or tropical/subtropical reservoirs might be particularly relevant in the tropics, where there is a lack of data and the use of equations originally developed for temperate systems may be inappropriate. We calculated two widely used TSIs for temperate lakes (TSItemp) or tropical reservoirs (TSItrop) and explored the deviations among TSI components in Brazilian reservoirs. When applied to our tropical/subtropical reservoirs, the TSItemp provided a conservative approach, with lower limits anticipating increasing trophic state classification. TSI components for Chl-a and SDD significantly deviated for both sets of equations, and these discrepancies were related to turbidity, water temperature, and cyanobacterial biomass. For TSItemp, but not for TSItrop, TSI values in relation to Chl-a and TP were also significantly different. All such deviations have important management implications especially when Chl-a, TP, and SDD are averaged in a single TSI, representing loss of information and less useful trophic state classifications. Our results demonstrate that tropical water bodies may respond to drivers of eutrophication differently than temperate systems, highlighting the need for more data to better inform management of these understudied ecosystems. As managers collect data from more tropical water bodies, regional models may offer even better understanding of factors influencing trophic state.

Individual Secchi disk measurements (975,760) were gathered from across the United States to understand regional distribution inwater transparency. Compiled Secchi diskmeasurements represented 14,421 US waterbodies. Average water transparency ranged from <0.1 to 31.6 m withwater transparencies <1.1 min 25% of the sampled waterbodies, <2.0 m in 50% of the waterbodies, and <3.3 m in 75% of the waterbodies. Of the population of examined waterbodies, 10% had mean Secchi measurements exceeding 4.8 m. US states with the lowest water transparency (<0.7 m) were Delaware, Louisiana, Mississippi, Nebraska, Oklahoma, and South Dakota, while the greatest water transparencies (>3.5 m) were in Alaska, Maine, Montana, New Hampshire, and Vermont. Regional differences in water transparency were identified across the US Environmental Protection Agency ecoregions (Level III), with lower water transparencies occurring in nutrient-rich regions and higher water transparencies occurring in nutrient-poor regions. Regional variability should be considered in the management of waterbodies at local to national levels.

FigureSAN FRANCISCO—Women with ductal carcinoma in situ (DCIS) can be reassured that radiotherapy does not appear to increase their risk of cardiovascular disease, according to research presented here at this year's Breast Cancer Symposium. But, another study shows that perioperative MRI does not reduce the risk of recurrence in women with DCIS. The two studies were featured in a presscast held in advance of the symposium, which is co-sponsored by the American Society of Breast Disease, American Society of Breast Surgeons, American Society of Clinical Oncology, American Society for Radiation Oncology, National Consortium of Breast Centers, and the Society of Surgical Oncology. No Increase in Risk of Cardiovascular Disease with RT for DCIS Recent concerns about potential overdiagnosis of DCIS make evaluation of the late effects of treatment such as cardiovascular disease (CVD) of great importance, according to the researchers, from the Netherlands. So it is reassuring, they said, that a large study showed that women receiving radiation therapy to treat DCIS had no increased risk of CVD compared with women in the general population or those treated for DCIS with surgery alone. The study data (Abstract 58) involved 10,468 Dutch women diagnosed with DCIS before age 75 between the years 1989 and 2004: 71 percent were treated with surgery alone (43 percent with mastectomy) and 28 percent with surgery plus radiotherapy. The first author, Naomi B. Boekel, MSc, a doctoral student in the Department of Epidemiology at the Netherlands Cancer Institute, reported that there was no difference at a median of 10 years in the risk of cardiovascular disease between the surgery-alone and the surgery-radiotherapy groups—nine percent vs. eight percent, respectively.STEVEN O'DAY, MD. STEVEN O'DAY, MD: “As new technologies are used, this [MRI] study grounds us to make sure we are actually making a difference. It's not that MRI can't be used—there are cases where it is important to obtain perioperative information with the sensitivity that MRI may give—but these data suggest its routine use in DCIS is not warranted.”Similarly, no difference in diagnosis of CVD was seen between women receiving left- vs. right-sided radiotherapy—seven vs. eight percent, respectively. She said that interestingly, DCIS survivors had a 30 percent lower risk of cardiovascular mortality compared with the general public, speculating that this might be due to lifestyle adaptation among women diagnosed with breast cancer, or conflicting risk factors between DCIS and CVD such as age at menopause, or that DCIS patients are perhaps more health conscious after a DCIS diagnosis. The moderator of the teleconference, Steven O'Day, MD, a member of the ASCO Communications Committee and Clinical Associate Professor of Medicine at the University of Southern California Keck School of Medicine and Director of Clinical Research at Beverly Hills Cancer Institute, said that older radiation studies clearly showed a correlation between radiation and cardiovascular toxicity when the fields were overlapping over the heart. But radiation therapy has been refined over the years, he said, and the strength of this study is that the data are relatively recent, 1998-2004, a time when more modern techniques of radiation therapy were being used. “What's reassuring about this study is that with aggressive treatment with radiotherapy there was not an increased risk of death and no increased risk of cardiovascular death,” he said. “This study allows us to feel comfortable continuing our aggressive treatment of DCIS.” Long-term Outcomes in DCIS Not Improved by MRI Adding MRI to mammography before or immediately after surgery was not associated with reduced local recurrence or reduced contralateral breast cancer rates among women with DCIS treated with lumpectomy, said researchers from Memorial Sloan-Kettering Cancer Center.NAOMI B. BOEKEL, MSC. NAOMI B. BOEKEL, MSC: “Compared with the general population, DCIS patients have a decreased risk of cardiovascular death, independent of treatment.”Their findings, from a large retrospective study, were presented by Melissa L. Pilewskie, MD, a breast surgeon there (Abstract 57 ). She said that MRI has a high false-positive rate, which can result in additional biopsies and delay in surgery. The report also noted that in a recent survey of U.S. surgeons, 37 percent routinely used MRI for patients with DCIS. Among 2,321 women who underwent a lumpectomy for DCIS between 1997 and 2010 at Memorial, 596 had received an MRI either before (81%) or immediately after surgery, and 1,725 had conventional imaging alone. After a median follow-up of 59 months, there was no statistically significant difference in five-year locoregional recurrence—8.5 percent with MRI vs. 7.2 percent without MRI. In the cohort of women who did not undergo radiotherapy, locoregional recurrence rates were about 10 and 13 percent, respectively. There was no statistically significant difference in five-year contralateral breast cancer either, at 3.5 percent for each group. Among women who did not receive radiation, the rates were 3.5 and 4.6 percent, respectively. Pilewskie said the difference in recurrence rates might be due to the fact that women who received MRI were younger, more likely to be premenopausal, to have a family history of breast cancer, and to receive radiation and endocrine therapy—all factors associated with higher-risk disease. These data, which were collected prospectively, along with previous studies showing that use of MRI does not decrease re-excision rates for women with DCIS, suggest that MRI is not associated with either improved short-term or long-term outcomes.MELISSA L. PILEWSKIE, MD. MELISSA L. PILEWSKIE, MD, said that the data from her prospective study, along with previous studies showing that use of MRI does not decrease re-excision rates for women with DCIS, suggest that MRI is not associated with either improved short-term or long-term outcomes.“As new technologies are used, this study grounds us to make sure we are actually making a difference,” O'Day commented. “It's not that MRI can't be used—there are cases where it is important to obtain perioperative information with the sensitivity that MRI may give—but these data suggest its routine use in DCIS is not warranted.” Women Not Aware of Their Breast Cancer Risk SAN FRANCISCO—In another study discussed during the pre-Symposium teleconference, more than 90 percent of women in a large-scale survey either under- or over-estimated their lifetime risk for developing breast cancer. And 40 percent said they had never discussed their personal breast cancer risk with a doctor (Abstract 4). Jonathan D. Herman, MD, an obstetrician-gynecologist at Hofstra North Shore-LIJ Medical School in New Hyde Park, NY, described a survey of 9,873 women age 35 to 70 who had undergone a mammogram at one of 21 participating centers. The women were asked to estimate their risk of developing cancer over the next five years and over their lifetime. They were also asked for demographic information and other data that could be used to calculate breast cancer risk. A woman's estimate was considered inaccurate if it differed from the calculated risk by more than 10 percent. Only 9.4 percent of women accurately estimated their risk; 44.7 percent underestimated and 45.9 percent overestimated the risk. Caucasian women were more likely to overestimate risk, Herman said, and African American, Asian, and Hispanic women were more likely to underestimate. His coauthor is his teenage daughter, Sarah M. Herman, who in 2010 when she was 13 questioned her father's contention that women did not understand their breast cancer risk. “Despite all the publicity, marches, and pink ribbons, it is disconcerting that only 9.4 percent could tell us what their breast cancer risk was,” Dr. Herman said. “We hope patients will ask their doctors what their numbers are, and that doctors will become aware of calculating risk so they can elevate the care of their patients.” The moderator of the teleconference, Steven O'Day MD, praised the study: Decisions about how best to do surveillance and potentially use chemoprevention are difficult decisions, even when we accurately know the risks. The results—not all that surprising—show that when only 10 percent of patients know their own risk, these decisions become almost impossible. Both under- and overestimations have significant consequences.”Co-researchers JONATHAN D. HERMAN, MD, and SARAH M. HERMAN. Co-researchers JONATHAN D. HERMAN, MD, and SARAH M. HERMAN, with the 15,000+ surveys in their study.O'Day pointed out that the study goes hand in hand with a recent article in the Journal of Clinical Oncology (2013;31:2942-2962), with a Clinical Practice Guideline on the use of pharmacologic interventions for breast cancer risk- reduction (OT, 8/10/13 issue). “In order to make final decision on chemoprevention, an accurate understanding of prognosis and risk, both from the patients' and physicians' perspectives, is going to be essential to making good, sound decisions,” he said. Dr. Jonathan Herman's co-researcher, his daughter Sarah, now 16, wrote this essay to describe their research: Breast Cancer Research Project By Sarah Herman For as long as I can remember I have had to listen to my father rant on and on about breast cancer. Just about two years ago, in the winter of 2010, I remember standing in my family's kitchen when he said that women should know more. They need to know their own risk numbers and they need to know their own risk factors. I could not believe it. With all of the publicity, walks, and the pink ribbons, how could women lack this knowledge when it's so easy to have? I jumped into the conversation. I wanted to learn if it was true what my father was telling me. It was then that my project was born. We decided to ask women what they knew about their personal risk. With a little help I put together a 25-question survey. I then went to my neighborhood radiology/mammography centers asking them to give out my survey. I was amazed when they said yes; I was all of 13 years old at the time. My goal was to collect as many as I could. At the start I only had a couple of radiology centers giving out my survey. I was excited and encouraged when I picked-up the first 50 responses. Over the next four months, I was able to add on another radiology center and then another. I began in January and by June 2011. I had 21 centers participating. Soon enough I was receiving around 1,000 surveys a month! I could not believe how much my project was growing. My dining room table was soon and still is covered with hundreds of surveys that I enter into the database daily. This work is not easy! After the first three thousand, I recruited a few friends, my parents and even my grandmother to help. I started high school in September. There was no way I would be able to enter them all. It's now two years into the project. There are more than 11,000 surveys entered. As the surveys were entered, I kept an eye on the results and I have really been surprised at what I saw. I asked women, “when was the last time they spoke with their doctor about their personal breast cancer risk?” Forty percent of women replied they never have. My data shows that more than 85 percent of women either underestimate, overestimate, or way overestimate their risk of getting breast cancer. It's true; we need to change how we educate because knowledge is power!

This article builds on a growing literature about collaborative environmental policymaking and assesses its use in relation to a major element of American water pollution policy—the total maximum daily load (TMDL) program. It extends current literature by tying collaborative policymaking to a key element of the federal Clean Water Act and by compiling information on the implementation of actions recommended in TMDL reports. We find that recommendations contained in TMDL reports are being implemented in many—but not all—of the TMDL-limited watersheds in Ohio and West Virginia. In addition, we find that the presence of a collaborative watershed group is positively associated with perceived progress in TMDL implementation. However, we also find that current efforts are far from sufficient, and we suggest that future efforts to understand collaborative watershed management should take account of TMDL processes and the federal policy structures in which they are embedded.

We used three different sizes of trap nets (small, medium, and large sizes of both mesh and throats) sampled at 6-h intervals to determine peak activity time(s) for fish along the deep vegetation line in Sandy Lake, Portage County, Ohio. Over 90% of the total catch comprised bluegill Lepomis macrochirus, largemouth bass Micropterus salmoides, pumpkinseed L. gibbosus, and black crappie Pomoxis nigromaculatus. All four species had their lowest catch per unit effort (CPUE) at night (2200-0400 hours). Different length-classes of pumpkinseeds and black crappies had peak CPUE during different times of the day. Smaller length-classes of all species (i.e., those captured in small and medium trap nets) had peak CPUE during either dawn (0400-1000 hours) or midday (1000-1600 hours), whereas the only piscivores captured in high abundance (black crappies 150-303 mm total length captured in large trap nets) had higher CPUE at dusk (1600-2200 hours) than during any other time of the day. It is possible that these activity patterns are affected by predation risk or food availability. These findings indicate that individual species or length-classes do not typically interact directly even though they use the same habitat. Therefore, when predicting potential species interactions in natural systems, it is important to consider diel changes in behavior. When possible, sampling schedules should take into account the activity patterns of the species of interest to ensure that information is obtained from the most appropriate time(s) of day to more accurately assess species interactions.

The Great North American Secchi Dip-In has continuously collected transparency data in North America since 1994. Volunteers collect the data during two weeks spanning Canada Day (July 1) and July 4th. More than 31,000 transparency records have been collected on 6,200 waterbodies. The Dip-In works through existing volunteer monitoring programs, which provides assurance that the data comes from trained volunteers. Transparency values obtained during this “snapshot” event are found to have a low year-to-year within-lake variability (5-6% RSD) and even lower if the data were detrended (3-4% RSD). Using data from waterbodies with five years or more of data, we used a Kendall’s Tau-b to detect temporal trends. Only 54 of 1,362 waterbodies were found to have significant (P = 0.5) decreases in transparency, while 61 had significant increases in transparency. An Ohio volunteer database was used to detect weekly variability throughout the season. The highest weekly variability occurred during the early spring. The second peak (3-4% RSD) occurred in late June, decreasing thereafter into the fall. Year-to-year transparency trends varied throughout the season in slope and significance throughout the season, suggesting that “snapshot” monitoring can provide an estimate of change for a specific seasonal period. The comparability of trends obtained by “snapshot” monitoring and whole-season monitoring will be discussed.

Trap nets of varying design are commonly used to assess fish populations, but the effect of the design on gear selectivity is not well known. In particular, it may be advantageous to use multiple net designs with different mesh and throat sizes to maximize the catch of specific length-classes and to minimize the risk of predation on small fish by larger fish. We compared the species composition, catch rate, and length distribution of fishes caught by three trap net designs with dimensions differing only in mesh size and throat size (0.6-cm delta mesh and 3.8-cm X 3.8-cm square throats, 1.3-cm square mesh and 7.6-cm X 7.6-cm square throats, or 2.5-cm square mesh and 12.7-cm X 12.7-cm square throats). A total of 3,473 fish of 18 species were captured from Sandy Lake, Portage County, Ohio, during 24 sample dates from June to August 1999. The large net design had a significantly higher average number of species captured (mean = 11) than the medium or small net design (means = 9 and 8, respectively). Whereas nets with larger mesh and throat size combinations typically caught larger fish for the six most commonly captured species, only rarely did nets capture fish as large or as small as possible based on their physical dimensions. Specific length-classes of some species were not captured in the nets or were very net design specific, indicating a possible difference in trap net vulnerability of different ontogenetic stages. We conclude that data from trap nets with different mesh and throat sizes should not be directly compared with each other, and that multiple net mesh and throat sizes (or even multiple gear types) should be used when a more complete picture of fish length and abundance is desired.

Little is known about nocturnal habitat selection by fishes under the risk of predation. Using a photoperiod of 15 h light: 9 h dark, we quantified the diel use of artificial macrophytes and open water by two size-classes of bluegill Lepomis macrochirus when the open water was empty (control), contained food, or contained both a caged predator and food. Small bluegills (6.2-7.7 cm total length) spent significantly more time in macrophytes in the predator and food treatment than in the control, followed by the food-only treatment, In addition, small bluegills spent significantly more time in macrophytes during the day than at night in all treatments. The frequency with which small bluegills were found in the same location in subsequent observations was significantly higher in the predator and food treatment during the day than in any other treatment and light combination. Large bluegills (10.2-13.0 cm total length) showed no difference in habitat use among treatments but spent significantly less time in macrophytes at night than during the day. There was no difference in the frequency with which large bluegills were found in the same location in subsequent observations among treatments or light levels. This suggests the potential for a diel littoral -pelagic habitat change by juvenile bluegills that would have important implications for the role of bluegills in lake food webs, including the possibility of nutrient translocation that could generate alternate stable states in lakes.

The ecoregion concept is a popular method of understanding the spatial distribution of the environment', however, it has yet to be adequately demonstrated that the environment is distributed in accordance with these bounded units. In this paper, we generated a testable hypothesis based on the current usage of ecoregions: the ecoregion classification will allow for discrimination between lakes of different water quality. The ecoregion classification should also be more effective better than a comparably scaled classification based on political boundaries, land-use class, or random grouping. To test this hypothesis we used the Environmental Monitoring and Assessment Program (EMAP) lake water chemistry data from the northeast United States. The water chemistry data were reduced to four components using principal component analysis. For comparison to an optimal grouping of these data we used K-means cluster analysis to define the extent at which these lakes could be segregated into distinct classes. Jackknifed discriminant analysis was used to determine the classification rate of ecoregions, the three alternative spatial classification methods, and the clustering algorithm. The classification based on ecoregions was successful for 35% of the lakes included in this study, in comparison to the clustered groups accuracy of 98%. These results suggest that the large scale spatial distribution of ecosystem types is more complicated than that suggested by the present ecoregion boundaries. Further tests of ecoregion delineations are needed and alternative large-scale management strategies should be investigated.

This study considered changes in the plankton communities of 50 Adirondack Mountain lakes, along an acidity gradient from pH 7.3 to 4.2. The objective was to test the hypothesis that changes in the biomass of certain species are compensated by opposite changes in the biomass of other species having similar ecosystem functions. This hypothesis was proposed by Frost et al. (1995); Linking Species and Ecosystems. Chapman and Hall, NY, pp. 224–239.) and referred to as `complementarity'. Results from the multi-lake survey, as well as data from two experimental studies, provide support for the hypothesis. With increasing acidity, there were declines in the number of plankton species, and pronounced changes in taxonomic composition. There were also reductions in food web complexity, measured as number of trophic links per species. The most acidic lakes displayed extreme dominance of a few taxa per trophic level, and characteristic acid-tolerant species such as Diaptomus leptopus (a calanoid copepod), Keratella taurocephala (a rotifer), and Chlamydomonas sp. (a chlorophyte alga). In contrast, the total biomass of producers and herbivores was unrelated to lakewater acidity. Acid lakes contained levels of phytoplankton biomass (chlorophyll a) consistent with measured levels of nutrients, and zooplankton biomass was consistent with its resource base (the phytoplankton). Experimental results indicated that complementary changes can occur rapidly at lower trophic levels when replacement species are already present in the community.

Transactions of the American Fisheries SocietyVolume 121, Issue 1 p. 141-141 Book Reviews Global Freshwater Quality: A First Assessment Robert Carlson, Robert Carlson Department of Biological Sciences, Kent State University, Kent, Ohio, 44242-0001 USASearch for more papers by this author Robert Carlson, Robert Carlson Department of Biological Sciences, Kent State University, Kent, Ohio, 44242-0001 USASearch for more papers by this author First published: January 1992 https://doi.org/10.1577/1548-8659-121.1.141AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume121, Issue1January 1992Pages 141-141 RelatedInformation

BACKGROUND Many water utilities that use surface water supplies have occasional-in some cases, frequent-problems with taste, odor, color, or high trihalomethane (THM) concentrations in their finished water. Regulatory agencies have set standards that are difficult and expensive to meet, and these standards most likely will be tightened in the future. The pollutants that cause these problems continue to enter surface water supplies, and may be doing so at greater rates as population increases and as agricultural production rises. Utilities may have to meet costly and difficult standards with increasingly deteriorated raw water quality.

ABSTRACT A continuous dose of aluminum sulfate was applied to the Cuyahoga River 500 m upstream of Lake Rockwell, a northeastern Ohio reservoir, to decrease phosphorus loading. After one week of treatment benthic invertebrates were eliminated at a site 60 m downstream from the application site, possibly through toxicity of intermediate forms of aluminum, and/or from oxygen depletion in the floe, catastrophic drift induced by low pH or aluminum toxicity and the treatment acting as a partial barrier to drift. Small numbers of invertebrates returned to the site three weeks after the application was terminated. The alum floe accumulation seemed to favor the re-establishment of oligochaetes. Downstream sites had reduced numbers of invertebrates, particularly chironomids, after five weeks of treatment, perhaps caused by the alum treatment. Continuous applications of alum may be more toxic than single-dose treatments because of the continuous presence of transitory forms of aluminum.

ABSTRACT Eutrophication in lakes and reservoirs is a recreational problem and a drinking water quality problem. A major concern is trihalomethane (THM) formation from the reaction of chlorine, a disinfectant, with organic matter in natural water during drinking water treatment. Trihalomethanes, such as chloroform, are known or suspected carcinogens. Algae and allochthonous humic substances are known contributors to the THM precursor pool. Other in-reservoir precursor sources, macrophytes, and sediments, have not been investigated. The authors examined precursor generation in an Ohio water supply reservoir. A three-year input-output study demonstrated that 30 percent of the precursors entering the treatment plant were generated within the reservoir. Laboratory experiments revealed that macrophytes and sediments produce THM precursors. Estimated THM precursor contributions to the reservoir from macrophyte growth and sediment release were small, but algal productivity and macrophyte decomposition may contribute more than one-third of the precursors during the summer.

ABSTRACT Lake Rockwell provides drinking water to Akron, Ohio. Algae and macrophytes cause increased treatment costs, user complaints, and concerns about water quality standards. The reservoir is very eutrophic. A diagnostic study performed in the laboratory with intact cores taken from littoral and anoxic sediments determined that oxic and anoxic sediments have a very high potential for phosphorus release. Only 19 percent of annual phosphorus external loading occurs between May and October, but apparently this summer loading triggers algal blooms in the upper reservoir that are transported downstream. Winter loading contributes to sediment phosphorus, and thus, to summer internal loading. Preliminary evaluations of proposed management steps revealed that harvesting of Myriophyllum spicatum that included root crown removal produced summer-long biomass control after a single harvest. Water quality deteriorated afterwards, however, suggesting that a late summer harvest might intercept senescence, and would be more appropriate. Soluble reactive phosphorus (SRP) entering the reservoir in September 1985 was intercepted with alum; apparently, this is the first reported use of alum for SRP removal. The treatment was successful, and 100 percent removal of SRP seems possible with higher alum doses.