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311.
Tim Caro Jeffrey Andrews Matthew Clark Monique Borgerhoff Mulder 《Conservation biology》2023,37(1):e14011
We considered a series of conservation-related research projects on the island of Pemba, Tanzania, to reflect on the broad significance of Beier et al.’s recommendations for linking conservation science with practical conservation outcomes. The implementation of just some of their suggestions can advance a successful coproduction of actionable science by small research teams. Key elements include, first, scientists and managers working together in the field to ensure feedback in real time; second, questions jointly identified by managers and researchers to facilitate engaged collaboration; third, conducting research at multiple sites, thereby broadening managers’ abilities to reach multiple stakeholders; and fourth, establishing a multidisciplinary team because most of the concerns of local managers require input from multiple disciplines. 相似文献
312.
313.
Brian D. Fox Brian P. Bledsoe Eleanor Kolden Matthew C. Kondratieff Christopher A. Myrick 《Journal of the American Water Resources Association》2016,52(2):420-442
Whitewater parks (WWPs) typically consist of instream structures that enhance recreational boating by constricting flow into a steep chute that generates a hydraulic jump in a downstream pool. Concerns have been raised that high velocities resulting from WWPs may be inhibiting fish movement during critical life stages. We evaluated the effects of WWPs on upstream fish passage by concurrently monitoring fish movement and hydraulic conditions at three WWP structures and three adjacent natural control (CR) sites in a wadeable river in northern Colorado. Fish movement was tracked with a network of Passive Integrated Transponder antennas over a 14‐month period. Individual fishes (n = 1,639), including brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss), were tagged and released within WWP and CR sites. Detailed hydraulic conditions occurring during the study period were evaluated with a fully 3D model. Results reveal the WWPs monitored in this study are not a complete barrier to upstream salmonid movement, but differences in passage efficiency from release location range from 29 to 44% in WWP sites and 37 to 63% for CR sites and the suppression of movement is related to body length. Small numbers of monitored nonsalmonids were inadequate to directly observe effects on their movement; however, it is highly probable that movement of smaller native fishes is also suppressed. Hydraulic modeling helps in the design of WWP structures that protect fish passage. 相似文献
314.
Daren R. Harmel Laura E. Christianson Matthew W. McBroom Douglas R. Smith Kori D. Higgs 《Journal of the American Water Resources Association》2016,52(5):1275-1279
The “Measured Annual Nutrient loads from AGricultural Environments” (MANAGE) database was published in 2006 to expand an early 1980s compilation of nutrient export (load) data from cultivated and pasture/range land at the field or farm scale. Then in 2008, MANAGE was updated with 15 additional studies, and nitrogen (N) and phosphorus (P) concentrations in runoff were added. Since then, MANAGE has undergone significant expansion adding N and P water quality along with relevant management and site characteristic data from: (1) 30 runoff studies from forested land uses, (2) 91 drainage water quality studies from drained land, and (3) 12 additional runoff studies from cultivated and pasture/range land uses. In this expansion, an application timing category was added to the existing fertilizer data categories (rate, placement, formulation) to facilitate analysis of 4R Nutrient Stewardship, which emphasizes right fertilizer source, rate, time, and place. In addition, crop yield and N and P uptake data were added, although this information was only available for 21 and 7% of studies, respectively. Inclusion of these additional data from cultivated, pasture/range, and forest land uses as well as artificially drained agricultural land should facilitate expanded spatial analyses and improved understanding of regional differences, management practice effectiveness, and impacts of land use conversions and management techniques. The current version is available at www.ars.usda.gov/spa/manage-nutrient . 相似文献
315.
Weeberb J. Réquia Petros Koutrakis Henrique Llacer Roig Matthew D. Adams 《Journal of the Air & Waste Management Association (1995)》2016,66(12):1284-1293
Exposure to traffic emission is harmful to human health. Emission inventories are essential to public health policies aiming at protecting human health, especially in areas with incomplete or nonexistent air pollution monitoring networks. In Brazil, for example, only 1.7% of municipal districts have a monitoring network, and only a few studies have reported data on vehicle emission inventories. No studies have presented emission inventories by municipality. In this study, we predicted vehicular emissions for 5570 municipal districts in Brazil during the period 2001–2012. We used a top-down method to estimate emissions. Carbon dioxide (CO2) is the pollutant with the highest emissions, with approximately 190 million tons per year during the period 2001–2012). For the other traffic-related pollutants, we predicted annual emissions of 1.5 million tons for carbon monoxide (CO), 1.2 million tons of nitrogen oxides (NOx), 209,000 tons of nonmethane hydrocarbons (NMHC), 58,000 tons of particulate matter (PM), and 42,000 tons for methane (CH4). From 2001 to 2012, CO, NMHC, and PM emissions decreased by 41, 33, and 47%, respectively, whereas those CH4, NOx, and CO2 increased by 2, 4, and 84%, respectively. We estimated uncertainties in our study and found that NOx was the pollutant with the lowest percentage difference, 8%, and NMHC with the highest one, 30%. For CO, CH4, CO2, and PM, the values were 22, 14, 21, and 20%, respectively. Finally, we found that during 2001 and 2012 emissions increased in the Northwest and Northeast. In contrast, pollutant emissions, except for CO2, decreased in the Southeast, South, and part of Midwest. Our predictions can be critical to efforts developing cost-effective public policies tailored to individual municipal districts in Brazil.
Implications: Emission inventories may be an alternative approach to provide data for air quality forecasting in areas where air quality data are not available. This approach can be an effective tool in developing spatially resolved emission inventories. 相似文献
316.
Inna E. Popova Matthew J. Morra 《Journal of environmental science and health. Part. B》2017,52(11):817-822
Although estrogens originating from dairy manure applied to agricultural soils as a fertilizer can potentially contaminate surface water and groundwater, the variables that control transport are poorly understood. Our objective was to assess the potential for off-site movement of endogenous dairy cattle estrogens when manure is applied on fields at agronomically relevant fertilization rates. Estrone (E1), 17α-estradiol (α-E2), and 17β-estradiol (β-E2) were used in laboratory sorption, desorption, and transformation incubations with both manure and an agriculturally relevant soil. Sorption on manure containing 44% organic carbon exceeded sorption on soil containing 0.8% organic carbon by 20 to 150 times, following the pattern of β-E2 > α-E2 > E1. Approximately 20% of E1 and 17% of α-E2 were desorbed from manure, whereas only about 4% of β-E2 was desorbed. Thirty to seventy percent of α-E2 and β-E2 were converted to E1 in soil and manure, making it imperative that transformation reactions be considered when predicting transport and potential biological effects in the environment. Overall results indicate that high organic carbon concentrations and relatively low amounts of desorption inhibit the potential for off-site transport of endogenous dairy manure estrogens. 相似文献
317.
In a landscape of fragmented private ownership, the need to coordinate game management across large areas presents challenges for landowners and public agencies alike. This paper describes how a recent reorganization of moose management in Norway achieves landscape-level planning while maintaining a tradition of local management by hunting teams. These two seemingly contradictory imperatives – coordinating wildlife management across large areas while keeping benefits and control in the hands of local resource users – are resolved through a nesting of management institutions, wherein the state serves a regulatory function and mid-level government (the county) serves to facilitate inter-local cooperation. This paper documents how the system is structured and describes the balance of incentives that enable the system to work. Information was gathered via interviews with staff at the Norwegian Directorate for Nature Management (now called the Norwegian Environment Agency), with wildlife management officials at the municipal level, with hunters, and from the most recent regulatory documents. 相似文献
318.
Christopher J. Salice Jamie G. Suski Matthew A. Bazar 《Environmental pollution (Barking, Essex : 1987)》2009,157(12):3457-3464
Although anthropogenic pollutants are thought to threaten reptilian species, there are few toxicity studies on reptiles. We evaluated the toxicity of Pb as lead acetate to the Western fence lizard (Sceloporus occidentalis). The acute lethal dose and sub-acute (14-day) toxicity studies were used to narrow exposure concentrations for a sub-chronic (60-day) study. In the sub-chronic study, adult and juvenile male lizards were dosed via gavage with 0, 1, 10 and 20 mg Pb/kg-bw/day. Mortality was limited and occurred only at the highest dose (20 mg Pb/kg-bw/d). There were statistically significant sub-lethal effects of 10 and 20 mg Pb/kg-bw/d on body weight, cricket consumption, organ weight, hematological parameters and post-dose behaviors. Of these, Pb-induced changes in body weight are most useful for ecological risk assessment because it is linked to fitness in wild lizard populations. The Western fence lizard is a useful model for reptilian toxicity studies. 相似文献
319.
Matthew Littleton 《Natural resources forum》2009,33(3):233-244
Despite numerous international commitments to promote transfer of climate-change-related technologies to developing countries, such transfers are not occurring at a rate fast enough to aid these nations in mitigating and adapting to the effects of climate change. The impact of the WTO Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) on transfer of these technologies is discussed through a detailed examination of relevant TRIPS provisions. The article also addresses options for improving technology transfer through exploitation of existing TRIPS flexibilities, modification of the Agreement, and other public and private legal and policy avenues. 相似文献
320.
We estimate an individual travel cost model for Great Sand Dunes National Park and Preserve (GSD) in Colorado using on-site,
secondary data. The purpose of the on-site survey was to help the National Park Service better understand the visitors of
GSD; it was not intended for a travel cost model. Variables such as travel cost and income were estimated based on respondents’
Zip Codes. Following approaches found in the literature, a negative binomial model corrected for truncation and endogenous
stratification fit the data the best. We estimate a recreational benefit of U.S. $89/visitor/year or U.S. $54/visitor/24-h
recreational day (in 2002 U.S. $). Based on the approach presented here, there are other data sets for national parks, preserves,
and battlefields where travel cost models could be estimated and used to support National Park Service management decisions. 相似文献