خيارات البحث
النتائج 1 - 10 من 18
Long-term changes in atmospheric nitrogen deposition and stream water nitrate leaching from forested watersheds in western Japan
2021
Chiwa, Masaaki
Japan receives nitrogenous air pollutants via long-range transport from China. However, emissions of nitrogenous air pollutants in China have stabilized or decreased in recent years. This study examined both the long-term trends in atmospheric nitrogen (N) deposition from the 1990s to the 2010s and the response of stream water nitrate (NO₃⁻) leaching from forested areas in western Japan. A long-term (1992–2018) temporal analysis of atmospheric N deposition in Fukuoka (western Japan) was conducted. Atmospheric bulk N deposition was collected at forested sites in a suburban forest (Swₑₛₜ) and a rural forest (Rwₑₛₜ) in western Japan during 2009–2018. Stream water samples were also collected from four locations at sites Swₑₛₜ and Rwₑₛₜ during the same period. Results showed that atmospheric N deposition in Fukuoka started to decrease from the mid-2000s at an annual rate of −2.5% yr⁻¹. The decrease in atmospheric N deposition was attributable mainly to decreased atmospheric ammonium (NH₄⁺) deposition, which caused greater contribution of NO₃⁻ deposition to atmospheric N deposition. Concentrations of NO₃⁻ in the stream water samples from three of the four locations decreased significantly at an annual rate of −3.7 to −0.7% yr⁻¹. However, stream water NO₃⁻ concentrations increased in one watershed where understory vegetation has been deteriorating owing to the increased deer population. This might weaken the recovery of N leaching from forested areas.
اظهر المزيد [+] اقل [-]Recent findings of halogenated flame retardants (HFR) in the German and Polar environment
2019
Dreyer, Annekatrin | Neugebauer, Frank | Lohmann, Nina | Rüdel, Heinz | Teubner, Diana | Grotti, Marco | Rauert, Caren | Koschorreck, Jan
To get an overview about distribution, levels and temporal trends of polybrominated diphenyl ethers (PBDE) and halogenated flame retardants (HFR) of emerging concern, different types of environmental samples archived in the German Environment Specimen Bank as well as fish filet samples from the Arctic (n = 13) and Antarctica (n = 5) were analysed for 43 substances (24 PBDE, 19 HFR) using a multi-column clean-up and GC-API-MS/MS or GC-MS. Sample types were herring gull egg (n = 3), blue mussel (n = 3) and eelpout filet (n = 3) from the German North- and Baltic Sea, bream filet (n = 7), zebra mussel (n = 6) and suspended particulate matter (SPM, n = 7) from German freshwater ecosystems as well as tree leaves (n = 9)/shoots (n = 10), soil (n = 4), earthworm (n = 4) and deer liver (n = 7) as representatives of German terrestrial ecosystems. PBDE and emerging HFR were present in each investigated matrices from Germany and Polar regions showing their widespread distribution. The presence in Arctic and Antarctic fish samples confirms their long-range transport potential. Average concentrations of total emerging HFR were highest in SPM (26 ng g⁻¹ dry weight (dw)), zebra mussel (10 ng g⁻¹ dw) and herring gull egg (2.6 ng g⁻¹ dw). Lowest levels were measured in fish filet samples from Antarctica (0.02 ng g⁻¹ dw). Average total PBDE concentrations were highest in bream filet (154 ng g⁻¹), herring gull egg (61 ng g⁻¹ dw), SPM (21 ng g⁻¹ dw), and zebra mussel 18 (ng g⁻¹) and lowest in deer liver (0.04 ng g⁻¹ dw). The patterns of non-fauna terrestrial samples (leaves, shoots, soil) as well as SPM were dominated by DBDPE and BDE209. Elevated proportions of DPTE and in most cases the absence of DBDPE characterized all fauna samples with the exception of Polar samples. Overall, emerging HFR appeared to be less bioaccumulative than PBDE. Temporal trends were generally decreasing with few exceptions such as DBDPE.
اظهر المزيد [+] اقل [-]Temporal and spatial trends of perfluoroalkyl substances in liver of roe deer (Capreolus capreolus)
2012
Falk, Sandy | Brunn, Hubertus | Schröter-Kermani, Christa | Failing, Klaus | Georgii, Sebastian | Tarricone, Kathrin | Stahl, Thorsten
For more than 50 years perfluoroalkyl substances (PFASs) have found worldwide industrial and household uses. Some PFASs are presumed to be persistent and bioaccumulative. Roe deer (Capreolus capreolus) are thought to be a suitable bioindicator for the accumulation of organic xenobiotics. Due to the ubiquitous nature of PFASs in the environment a retrospective study on temporal trends was carried out. A total of 110 deer liver pools collected from 1989 to 2010 in Germany were analyzed for their levels of PFASs. The highest concentrations were measured for perfluorooctane sulfonate (PFOS) (median 6.3 μg/kg). Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were detected with median concentrations of 0.5 μg/kg, 1.2 μg/kg and 0.3 μg/kg, respectively, while concentrations of the other PFASs were below the limit of quantification. PFOS concentrations decreased significantly (rₛ = −0.741; p = <0.0001) from 9.2 μg/kg in 2000 to 1.8 μg/kg in 2010.
اظهر المزيد [+] اقل [-]Chronic effects of lead (Pb) on bone properties in red deer and wild boar: Relationship with vitamins A and D3
2013
Rodríguez-Estival, Jaime | Álvarez-Lloret, Pedro | Rodríguez-Navarro, Alejandro B. | Mateo, Rafael
Here we study the occurrence of abnormalities on bone tissue composition and turnover mechanisms through the Pb-mediated disruption of vitamins A and D in wild ungulates living in a lead (Pb)-polluted mining area. Red deer (Cervus elaphus) and wild boar (Sus scrofa) from the mining area had significantly higher liver and bone Pb levels than controls, which were associated with the depletion of liver retinyl esters and the corresponding increase of free retinol levels both in deer and boar from the mining area. Pb-exposed adult deer had lower carbonate content in bone mineral than controls, which was associated with the increased free retinol percentage. In wild boar, the degree of bone mineralization was also positively associated with higher burdens of retinyl esters. These results suggest that Pb-associated changes in bone composition and mineralization is likely influenced by the depletion of vitamin A in wildlife exposed to environmental Pb pollution.
اظهر المزيد [+] اقل [-]Antimicrobial resistant Escherichia coli in Scottish wild deer: Prevalence and risk factors
2022
Elsby, Derek T. | Zadoks, Ruth N. | Boyd, Kenneth | Silva, Nuno | Chase-Topping, Margo | Mitchel, Mairi C. | Currie, Carol | Taggart, Mark A.
Antimicrobial resistance (AMR) is a recognised threat to global health. Obtaining data on the prevalence of AMR in environmental bacteria is key to understanding drivers and routes of transmission. Here, 325 Shiga toxin negative deer faecal samples—gathered from across the Scottish mainland—were screened for the presence of AMR Escherichia coli and investigated for potential risk factors associated with AMR occurrence. E. coli with resistance to antimicrobials of clinical health concern, including carbapenems and 3rd generation cephalosporins, were targeted. Ninety-nine percent of samples yielded E. coli, and the prevalence of resistant E. coli at the level of faecal samples was 21.8% (n = 71) for tetracycline, 6.5% (n = 21) for cefpodoxime, 0.3% for ciprofloxacin (n = 1), with no recorded resistance to meropenem. Potential risk factors for tetracycline and cefpodoxime resistance were investigated. The presence of broadleaved woodlands was significantly associated with both AMR phenotypes, which may relate to land use within or around such woodlands. Associated risk factors varied across resistance phenotype and deer species, with proximity or density of horses an indicator of significantly decreased and increased risk, respectively, or tetracycline and cefpodoxime resistance in E. coli from roe deer, but not from red deer. Distance from wastewater treatment plants was a significant risk factor for tetracycline resistance in E. coli from red deer but not from roe deer. Data indicated that AMR E. coli can occur in wild deer populations that are not directly exposed to the selective pressure exerted by antimicrobial treatment. Overall, resistance to critically important antimicrobials was found to be low in the studied population, suggesting no immediate cause for concern regarding human health. Utilising existing culling frameworks, wild deer in Scotland could function well as a sentinel species for the surveillance of AMR in the Scottish environment.
اظهر المزيد [+] اقل [-]Impacts of marine debris on wild animals in the coastal area of Korea
2013
Hong, Sunwook | Lee, Jongmyoung | Jang, Yong Chang | Kim, Yŏng-jun | Kim, Hee Jong | Han, Donguk | Hong, Sang Hee | Kang, Daeseok | Shim, Won Joon
Over the last decade, marine debris has become a major factor affecting the coastal ecosystem of Korea. This study compiled information regarding how marine debris impacts wildlife in Korea. Cases of marine debris impacting wildlife were collected from experts of various fields and from local participants through an open access website from February 2010 to March 2012. A total of 21 species were affected by marine debris: 18 species of birds, 2 species of mammals, and 1 species of crustacean. Five threatened or protected species were identified: black-faced spoonbill, finless porpoise, water deer, whooper swan, and greater painted snipe. Recreational fishing gears were the types of debris that most frequently impacted wildlife, especially birds. Black tailed gulls were the most vulnerable species to recreational fishing hooks and lines. Although it was preliminary, this study revealed that recreational fishing activities should be prioritized when managing marine debris in Korea.
اظهر المزيد [+] اقل [-]Marsh Soils as Potential Sinks for Bacteroides Fecal Indicator Bacteria, Waccamaw National Wildlife Refuge, Georgetown, SC, USA
2014
A soil core collected in a tidal freshwater marsh in the Waccamaw National Wildlife Refuge (Georgetown, SC) exuded a particularly strong odor of cow manure upon extrusion. In order to test for manure and determine its provenance, we carried out microbial source tracking using DNA markers for Bacteroides, a noncoliform, anaerobic bacterial group that represents a large proportion spectrum of the fecal population. Three core sections from 0–3 cm, 9–12 cm, and 30–33 cm were analyzed for the presence of Bacteroides. The ages of core sediments were estimated using²¹⁰Pb and¹³⁷Cs dating. All three core sections tested positive for Bacteroides DNA markers related to cow or deer feces. Because cow manure is stockpiled, used as fertilizer, and a source of direct contamination in the Great Pee Dee River/Winyah Bay watershed, it is very likely the source of the Bacteroides that was deposited on the marsh. The mid-points of the core sections were dated as follows: 0–3 cm, 2009; 9–12 cm, 1999, and 30–33 cm, 1961. The presence of Bacteroides at different depths/ages in the soil profile indicates that soils in tidal freshwater marshes are, at the least, capable of being short-term sinks for Bacteroides and, may have the potential to be long-term sinks of stable, naturalized populations.
اظهر المزيد [+] اقل [-]Investigation of technology for composting mixed deer manure and straw
2021
Wang, Hanxi | Yao, Difu | Xu, Jianling | Liu, Xuejun | Sheng, Lianxi
Composting is an effective method for utilizing agricultural straw waste and livestock manure resources. Using deer manure and corn straw as raw materials, the changes in various indexes were studied during composting under different initial C/N ratios, initial moisture contents, and particle sizes of corn straw, and compost maturity was evaluated. Moisture content, total organic carbon content, and C/N ratio all declined during composting, while total nitrogen, total phosphorus, total potassium, pH, germination index, and electrical conductivity increased. The grey relational analysis method was used to evaluate maturity. The results showed that a mixture of stalk and deer manure with initial moisture content of 55%, initial C/N ratio of 30:1, and a straw particle size of 1.5–3.5 cm constituted the optimal experimental conditions. Taguchi analysis indicated that initial moisture content exerted the greatest influence on compost maturity, followed by initial C/N ratio and crushed straw particle size. This study provides an important reference for the utilization of compost derived from a mixture of livestock manure and straw.
اظهر المزيد [+] اقل [-]An Analysis of Leachate Constituents and Pathogen Destruction in Deer Mortality Static Windrow Composting
2013
Donaldson, Bridget M. | Smith, Garrett P. | Kweon, Young-Jun | Sriranganathan, Nammalwar
Approximately 1.1 million deer–vehicle collisions occur in the United States each year. The predominant methods of disposing of these carcasses (landfill and burial) have several costly disadvantages, including long travel distances to landfills, increasing landfill restrictions, and lack of viable burial areas. Some states have found static compost windrows to be an easy and cost-effective carcass management technique. This type of composting involves the construction of passively aerated static piles, which do not require the materials turning needed with more traditional composting methods. In this study, deer mortality static compost windrows were monitored for 1 year. Windrows were analyzed for pathogen destruction and the degree to which underlying soil filtered leachate contaminants. In response to high windrow temperatures, indicator pathogens Escherichia coli and Salmonella were reduced by 99.99 % the first sampling day (day 7) and ascarids were deemed non-viable by day 77. Soil filtration of leachate was effective in reducing concentrations of ammonia, chloride, and total organic carbon. Nitrate, a contaminant of particular regulatory concern, had an estimated mass contaminant loss of 2.1 kg/ha, compared to the estimated 9 to 50 kg/ha loss from fertilizer application of common agronomic crops. Results of this study indicate that with properly constructed static compost windrows, (1) high temperatures effectively destroy indicator pathogens; (2) the natural filtration of leachate through soil reduces deer mortality contaminant concentrations; and (3) the low volume of leachate (i.e., two percent of the precipitation that fell on windrows) results in nominal losses of nitrate and other contaminants.
اظهر المزيد [+] اقل [-]Lead exposure in consumers of culled invasive alien mammals in El Palmar National Park, Argentina
2021
Tammone, Agostina | Caselli, Andrea Elsa | Condorí, Walter Ezequiel | Fernandez, Valentina | Estein, Silvia Marcela | Vanstreels, Ralph Eric Thijl | Sosa, Cristian | Delaloye, Aldo | Uhart, Marcela María
Consumption of meat from animals hunted with Pb ammunition can cause toxic accumulation with consequent health risks, even if relatively small amounts are consumed in each exposure. In El Palmar National Park, Argentina, invasive alien mammals, wild boar (Sus scrofa) and axis deer (Axis axis), are culled with Pb ammunition and their meat is consumed. In this study, we evaluated blood Pb concentrations in 58 consumers of culled game and examined Pb exposure risk according to their demographics, duty, and consumption habits. Likewise, the likelihood of exposure was evaluated by quantifying Pb concentrations in meat samples of seven culled axis deer. Twenty-seven participants (46%) had detectable blood Pb levels (limit of detection = 3.3 μg/dL), with an average 4.75 ± 1.35 μg/dL (geometric mean ± geometric S.D.); the average for all participants was 3.25 ± 1.51 μg/dL. Blood Pb concentrations were significantly higher in hunters, in participants who reported consuming game meat more than 5 times per week, and in participants who reported frequently consuming cured game meat (compared to cooked or pickled). Pb concentration varied significantly along the trajectory of the bullet in deer muscle, being highest at mid-point but with detectable Pb levels even in distant tissue samples (control), suggesting potential for dietary intake by consumers. These findings provide evidence of Pb exposure risk in consumers and emphasize the relevance of replacing Pb ammunition with non-toxic alternatives. This change would reduce dietary exposure in frequent consumers and allow the use of game meat as safe food for people whilst eliminating collateral risks to wild animals and the environment.
اظهر المزيد [+] اقل [-]