Connectivity in priority area selection for conservation

The spatial relations of sites within networks of priority areas for conservation is critical to the long-term maintenance of key genetic, population and ecosystem processes. However, these relations have received relatively little attention in the development of mathematical methods for objectively identifying such networks. Here we present a novel heuristic for incorporating connectivity explicitly as part of the model constraints, provide an integer linear programming formulation for the same problem, describe an integer cutting procedure which defines a sequence of non-decreasing lower bounds on the optimal solution and report the results of some computational experiments using these algorithms.     

Screening for Selected Human Pharmaceuticals and Cocaine in the Urban Streams of Manaus,Amazonas, Brazil

Pharmaceuticals and illicit drugs are contaminants that are generally ubiquitous in wastewater treatment plant effluents with their release into the environment being well understood in North America, Europe, and Asia. There is, however, less information on the release of human pharmaceuticals and illicit drugs from regions undergoing rapid land use, economical, and social changes, such as Brazil. This encompasses many areas in the tropical zone where releases of emerging contaminants may impact pristine, bio‐diversity rich ecosystems. In this study, the occurrence of human pharmaceuticals and the illicit drug cocaine was determined in the Rio Negro and two of its tributaries that receive large amounts of untreated sewage, the Igarapé Mindu and the Igarapé do 40, passing through the city of Manaus, Brazil. In addition to cocaine and its metabolite, benzoylecognine, propranolol, diclofenac, amitriptyline, carbamazepine, carbamazepine‐epoxide, citalopram, metoprolol, carisoprolol, and sertraline were all detected in two urban tributaries at low ng/l concentrations similar to those typically found in urban surface waters. Concentrations in the Rio Negro were typically lower than detection limits due to the large level of dilution, although traces of a range of pharmaceuticals were detected in the Rio Negro in proximity of the confluence of the urban streams. The data represent new information on the emissions of pharmaceuticals from a newly industrialized region of Brazil.     

Assessing the Potential Effects of Fungicides on Nontarget Gut Fungi (Trichomycetes) and Their Associated Larval Black Fly Hosts

Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far‐reaching consequences within aquatic ecosystems.     

Western Land Managers will Need all Available Tools for Adapting to Climate Change,Including Grazing: A Critique of Beschta et al.

In a previous article, Beschta et al. (Environ Manag 51(2):474–491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and their publication is more of an opinion article. Their conclusions do not reflect the complexities associated with herbivore grazing. Because grazing is a complex ecological process, synthesis of the scientific literature can be a challenge. Legacy effects of uncontrolled grazing during the homestead era further complicate analysis of current grazing impacts. Interactions of climate change and grazing will depend on the specific situation. For example, increasing atmospheric CO₂ and temperatures may increase accumulation of fine fuels (primarily grasses) and thus increase wildfire risk. Prescribed grazing by livestock is one of the few management tools available for reducing fine fuel accumulation. While there are certainly points on the landscape where herbivore impacts can be identified, there are also vast grazed areas where impacts are minimal. Broad scale reduction of domestic and wild herbivores to help native plant communities cope with climate change will be unnecessary because over the past 20–50 years land managers have actively sought to bring populations of native and domestic herbivores in balance with the potential of vegetation and soils. To cope with a changing climate, land managers will need access to all available vegetation management tools, including grazing.     

Testosterone upregulates lipoprotein status to control sexual attractiveness in a colorful songbird

A salient feature of many secondary sexual characteristics in animals is that their expression is controlled by sex-steroid hormones. However, for only a few types of ornaments do we know the precise molecular mechanism by which androgens like testosterone (T) enhance trait production. We studied the red carotenoid-based beak of male zebra finches (Taeniopygia guttata), which serves as a sexually selected trait and is thought to be T dependent. In previous research, we demonstrated that the extent to which male finches produce lipoproteins in the bloodstream, which bind carotenoid pigments acquired from the diet and transport them to peripheral tissues, regulates the accumulation of carotenoids in the body and beak pigmentation. Here we show that T acts to upregulate lipoprotein production and allows male zebra finches to display flashy, sexually attractive coloration. Levels of circulating T in blood positively and significantly predicted lipoprotein profile (as measured by cholesterol levels), blood carotenoid concentration, and beak color. Exogenous T administration elevated cholesterol and carotenoid status as well as beak redness. Last, experimental inhibition of T (using the anti-androgen flutamide) downregulated lipoprotein production and carotenoid circulation and faded the beak. This androgen- and lipoprotein-mediated system represents one of the more detailed physiological mechanisms underlying the development of a sex-steroid-dependent trait in animals.     

Residential Water Demand Management: Lessons from Aurora,Colorado1

Abstract: Residential water demand is a function of several factors, some of which are within the control of water utilities (e.g., price, water restrictions, rebate programs) and some of which are not (e.g., climate and weather, demographic characteristics). In this study of Aurora, Colorado, factors influencing residential water demand are reviewed during a turbulent drought period (2000‐2005). Findings expand the understanding of residential demand in at least three salient ways: first, by documenting that pricing and outdoor water restriction policies interact with each other ensuring that total water savings are not additive of each program operating independently; second, by showing that the effectiveness of pricing and restrictions policies varies among different classes of customers (i.e., low, middle, and high volume water users) and between predrought and drought periods; and third, in demonstrating that real‐time information about consumptive use (via the Water Smart Reader) helps customers reach water‐use targets.     

FTABLE Generation Method Effects on Instream Fecal Bacteria Concentrations Simulated With HSPF1

Abstract: Computer simulation models are used extensively for the development of total maximum daily loads (TMDLs). Specifically, the Hydrological Simulation Program‐FORTRAN (HSPF) is used in Virginia for the development of TMDLs for bacteria impairments. HSPF estimates discharge from a reach using function tables (FTABLES). The FTABLE relates stream stage, surface area, and volume to discharge from a reach. In this study, five FTABLE estimation methods were assessed by comparing their effect on various simulation outputs. Four “field‐based” methods used detailed cross‐sectional data collected via site surveys. A fifth “digital‐based” method used digital elevation data in combination with the Natural Resources Conservation Service Regional Hydraulic Geometry Curves. Sets of FTABLEs created using each method were used in simulations of instream bacteria concentration for a Virginia watershed. Several statistics relating to instream bacteria including long‐term average concentration, die‐off, and the violation rate of Virginia’s bacteria criterion were compared. The pair‐wise Student’s t‐test was used for the comparison. The HSPF simulations that used FTABLES estimated from digitally based data consistently produced significantly higher long‐term average instream fecal bacteria concentrations, significantly lower instream fecal bacteria die‐off, which is related to differences in residence time in the streams, and significantly higher water quality criterion violation rates.     

Urban Domestic Gardens (XIV): The Characteristics of Gardens in Five Cities

Domestic gardens make substantial contributions to the provision of green space in urban areas. However, the ecological functions provided by such gardens depend critically on their configuration and composition. Here, we present the first detailed analysis of variation in the composition of urban gardens, in relation to housing characteristics and the nature of the surrounding landscape, across different cities in the United Kingdom. In all five cities studied (Belfast, Cardiff, Edinburgh, Leicester, and Oxford), garden size had an overwhelming influence on garden composition. Larger gardens supported more of the land-use types recorded, in greater extents, and were more likely to contain particular features, including tall trees and mature shrubs, areas of unmown grass and uncultivated land, vegetable patches, ponds, and composting sites. The proportional contribution of non-vegetated land-uses decreased as garden area increased. House age was less significant in determining the land-use within gardens, although older houses, which were more likely to be found further from the urban edge of the city, contained fewer hedges and greater areas of vegetation canopy >2 m in height. Current UK government planning recommendations will ultimately reduce the area of individual gardens and are thus predicted to result in fewer tall trees and, in particular, less vegetation canopy >2 m. This might be detrimental from ecological, aesthetic, social, and economic stand points.     

A combined model–observation approach to estimate historic gridded fields of PM2.5 mass and species concentrations

This paper introduces a methodology for estimating gridded fields of total and speciated fine particulate matter (PM_2.5) concentrations for time periods and regions not covered by observational data. The methodology is based on performing long-term regional scale meteorological and air quality simulations and then integrating these simulations with available observational data. To illustrate this methodology, we present an application in which year-round simulations with a meteorological model (the National Center for Atmospheric Research/Penn State Mesoscale Model, hereafter referred to as MM5) and a photochemical air quality model (the Community Multiscale Air Quality Model, hereafter referred to as CMAQ) have been performed over the northeastern United States for 1988–2005. Model evaluation results for total PM_2.5 mass and individual species for the time period from 2000 to 2005 show that model performance varies by species, season, and location. Therefore, an approach is developed to adjust CMAQ output with factors based on these three variables. The adjusted model values for total PM_2.5 mass for 2000–2005 are compared against independent measurements not utilized for the adjustment approach. This comparison reveals that the adjusted model values have a lower root mean square error (RMSE) and higher correlation coefficients than the original model values. Furthermore, the PM_2.5 estimates from these adjusted model values are compared against an alternate method for estimating historic PM_2.5 values that is based on PM_2.5/PM₁₀ ratios calculated at co-located monitors. Results reveal that both methods yield estimates of historic PM_2.5 mass that are broadly consistent; however, the adjusted CMAQ values provide greater spatial coverage and information for PM_2.5 species in addition to total PM_2.5 mass. Finally, strengths and limitations of the proposed approach are discussed in the context of potential uses of this method.