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1.
Texto & contexto enferm ; 29: e20180310, Jan.-Dec. 2020.
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: biblio-1101979

RESUMO

ABSTRACT Objective: to analyze adherence to the nursing guidelines for home care of bone marrow transplant recipients from an ecosystem perspective. Method: descriptive, exploratory study with a qualitative approach, using Content Analysis for data analysis, with theoretical and philosophical ecosystem support. The interviews, carried out in bone marrow transplant services, in Brazil and Spain, were guided by an instrument developed by the researchers which contained 25 closed and ten open questions. 40 users participated who met the inclusion criteria. Data collection was carried out from July 2016 to October 2017. Results: the Orientations category emerged from the data which then gave rise to the subcategories: Interactive relational actions; and, actions and behaviors that interfered in the success of the transplant. Some users, due to excessive information at the time of discharge, were unable to assimilate or carry out the guidelines received; others, during the hospitalization phase, apprehended them and absorbed them in order to use them in the home ecosystem space after transplantation. Conclusion: part of the users followed only the guidelines that best adapted to their daily lives and, for others, after hospital discharge, they caused doubts and insecurities regarding the care to be performed at home. It is necessary for the user to identify the constituent elements of their home ecosystem and learn, through communication and information, how they interfere in post-hospital discharge care. Therefore, it is necessary to create communication and information mechanisms that enable the dynamic process between the constituent elements of the ecosystem, biotic and abiotic, so that they have interaction and sustainability and can be practiced by the user.


RESUMEN Objetivo: analizar el cumplimiento de las directrices de la enfermera para el cuidado domiciliario de los receptores de trasplante de médula ósea en una perspectiva ecosistémica. Método: descriptivo, exploratorio, con un enfoque cualitativo, utilizando el análisis de contenido para el análisis de datos, con soporte teórico y filosófico del ecosistema. Las entrevistas, realizadas en los servicios de trasplante de médula ósea, en Brasil y España, fueron guiadas por un instrumento desarrollado por los investigadores, que contenía 25 preguntas cerradas y diez abiertas. Participaron 40 usuarios que cumplieron con los criterios de inclusión. La recolección de datos se realizó entre julio de 2016 y octubre de 2017. Resultados: la categoría Orientaciones surgió de los datos y originó las subcategorías: acciones relacionales interactivas, acciones y comportamientos que interfirieron en el éxito del trasplante. Algunos usuarios, debido a la información excesiva al momento del alta, no pudieron asimilar y llevar a cabo las pautas recibidas, otros, en el curso de la fase de hospitalización, los detuvieron para absorberlos para su atención en el espacio del ecosistema del hogar en el pos trasplante. Conclusión: parte de lós usuários siguió solo las pautas que mejor se adaptaron a su vida diaria y para otros, después del alta hospitalaria, causaron dudas e inseguridades com respecto a La atención que se practica em elhogar. Es necesario que el usuario identifique los elementos constitutivos del ecosistema de su hogar y aprenda, a través de la comunicación y la información, cómo interfieren en la atención hospitalaria posterior al alta. Por lo tanto, es necesario crear mecanismos de comunicación e información que permitan el proceso dinámico entre los elementos constitutivos del ecosistema, bióticos y abióticos, para que tengan interacción y sostenibilidad y puedan ser practicados por el usuario.


RESUMO Objetivo: analisar a adesão às orientações do enfermeiro para o cuidado domiciliar do transplantado de medula óssea na perspectiva ecossistêmica. Método: descritivo, exploratório, com abordagem qualitativa, utilizando-se para a análise dos dados a Análise de Conteúdo, com apoio teórico-filosófico ecossistêmico. As entrevistas, realizadas em serviços de transplante de medula óssea, no Brasil e Espanha, foram norteadas por um instrumento elaborado pelas pesquisadoras, contendo 25 questões fechadas e dez abertas. Participaram 40 usuários que cumpriram os critérios de inclusão. A coleta de dados foi realizada de julho de 2016 a outubro de 2017. Resultados: a categoria Orientações emergiu dos dados e originou as subcategorias: Ações relacionais interativas; e, ações e comportamentos que interferiram no sucesso do transplante. Alguns usuários, por excesso de informações no momento da alta, não conseguiram assimilar e desempenhar as orientações recebidas; outros, no transcorrer da fase de internação, as apreenderam absorvê-las para o cuidado no espaço ecossistêmico domiciliar no pós-transplante. Conclusão: parte dos usuários seguiu somente as orientações que melhor se adaptaram ao seu cotidiano e, para outros, no pós-alta hospitalar, ocasionaram dúvidas e inseguranças em relação ao cuidado a ser praticado no domicílio. Faz-se necessário que o usuário identifique os elementos constituintes do seu ecossistema domiciliar e conheça, por meio da comunicação e informação, como interferem no cuidado pós alta hospitalar. Portanto, é preciso criar mecanismos de comunicação e informação que possibilitem o processo dinâmico entre os elementos constituintes do ecossistema, bióticos e abióticos, para que tenham interação e sustentabilidade e possam ser praticados pelo usuário.


Assuntos
Humanos , Adulto , Adulto Jovem , Transplante , Medula Óssea , Transplante de Medula Óssea , Transplantes , Cuidados de Enfermagem , Enfermagem , Ecossistema , Transplantados , Cooperação e Adesão ao Tratamento , Habitação
2.
Environ Monit Assess ; 192(11): 670, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33009644

RESUMO

Antarctica is considered as one of the most pristine areas on Earth. However, increasing intensity of human presence on the sixth continent (scientific operations, functioning of the numerous scientific stations, tourism activities) makes it crucial to investigate the level of environmental pollution within the vulnerable ecosystem of Antarctica. Soils play a significant role in processes of accumulation, mobilization, redistribution of chemical elements within landscapes, and ecosystems. The aim of this work was to analyze the levels of 17 polycyclic aromatic hydrocarbons and eight trace elements in soils of King George and Ardley islands, Western Antarctica. Moreover, our work was aimed to determine the trends and reasons of anthropogenic pollution of Antarctic soils and characterization of accumulation levels of trace elements and PAHs. Results showed the predominance of light PAHs in all studied sites. The content of benzo(a)pyrene does not exceed the threshold concentration (adopted by different national environmental legislation systems). At the same time, the content of benzo(a)pyrene, which is a marker of anthropogenic contamination, is relatively low or equal to 0 in soils of reference landscapes. Cu and Zn were found as most abundant elements in all studied soils. The highest lead concentration content has been described in soil from Bellingshausen station. In general term, obtained Igeo values for trace elements in all samples were under or slightly above the 0 level, indicating low to moderate pollution of the studied soils. This study also contributes new data on trace element accumulation in soils strongly influenced by ornithogenic factor. Principal component analysis allowed to estimate the probable sources of specific trace metals and their relationship with soil variables. Ornithogenic factor has been also revealed as a driver for some trace element accumulation especially in breeding penguin colonies. High contents of organic matter in ornithogenic habitats could increase trace metal mobility, environmental risks for surrounding terrestrial environments should be considered.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Oligoelementos/análise , Regiões Antárticas , Ecossistema , Monitoramento Ambiental , Humanos , Ilhas , Solo
3.
J Environ Qual ; 49(1): 61-73, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016353

RESUMO

Land reclamation in the Athabasca oil sands region requires construction of entire soil profiles from materials salvaged during mining. Although much attention has been paid to the limited supply of suitable topsoil materials and their impact on ecosystem recovery, suitable clean subsoil materials are also in limited supply, and their efficient and effective use is an important consideration for land managers in the region. Using data from an oil sands reclamation site in northern Alberta, Canada, we compared soil and foliar nutrients to a wildfire-impacted reference ecosystem with a similarity index. Specifically, we evaluated the similarity of forest floor-mineral mix (FFM) and peat-mineral mix (PM) as topsoil, as well as the effect of different depths of salvaged B and C horizon subsoil with PM on top. All reclamation treatments were planted with jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.), which were used to examine foliar nutrient concentrations. Individual macronutrient concentrations were different among treatments in total soil nutrients, but differences decreased in soil bioavailable nutrients and disappeared altogether in foliar nutrients. The similarity index revealed that distinct differences existed between treatments, with FFM being the most similar to the wildfire site. It also revealed a potential deficiency in foliar and soil bioavailable Mn on PM, and that increased water content of deeper subsoils had little to no effect. With use of this nutrient profile similarity index, reclamation practitioners may be able to determine if different soil prescriptions lead to higher levels of similarity to natural ecosystems more quickly.


Assuntos
Ecossistema , Campos de Petróleo e Gás , Alberta , Animais , Nutrientes , Ovinos , Solo
4.
J Environ Qual ; 49(1): 106-118, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016362

RESUMO

Plant nursery runoff commonly contains pesticides and nutrients that often threaten aquatic ecosystems. Constructed wetlands could be a tool to remove pesticides and nutrients from nursery runoff but have not been extensively studied in this setting. Two field-scale constructed wetlands (one subsurface-flow constructed wetland [SFCW] and one free-surface constructed wetland [FSCW]) were implemented and monitored for water quality improvement. The SFCW demonstrated significant mass reduction of 78% or greater for nitrate, orthophosphate, total nitrogen, total phosphorus, and total suspended solids. The SFCW also demonstrated significant mass reduction of 79% or greater for 10 of the 12 pesticide compounds detected in over half of the collected samples. The FSCW demonstrated significant mass reduction of 46% or greater for all nonpesticide analytes except total nitrogen. Loading rate and actual storage volume compared with inflow volume likely affected performance. Reduced size and increased loading rate of the FSCW likely reduced its ability to effectively reduce pesticides. Results from this study indicate that constructed wetlands are likely an effective tool for nursery runoff management. When designing and implementing constructed wetlands, it is important for practitioners to consider the tradeoff between system size (additional cost and land otherwise dedicated to production) and performance.


Assuntos
Poluentes Ambientais , Áreas Alagadas , Ecossistema , Nitrogênio , Fósforo
5.
J Environ Qual ; 49(1): 236-245, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016366

RESUMO

Antimicrobials used in livestock production can be present in manure via excretion in the feces and/or urine. Application of raw or processed (composted or stockpiled) manure to crop and pasture land as a plant nutrient source can result in antimicrobial transport to surface waters via rainfall or snowmelt runoff. Little is known regarding antimicrobial persistence in aquatic ecosystems. Consequently, dissipation of environmentally relevant concentrations of three veterinary antimicrobials (lincomycin, chlortetracycline, and sulfamethazine) was studied in three wetlands on the Canadian Prairies. Study wetlands were fortified in the fall to simulate antimicrobial transport via rainfall runoff from fall manure applications to the wetland catchments. After fortification, water column concentrations of all three antimicrobials decreased through September and October. Plotting natural logarithm values of antimicrobial concentration against time resulted in linear relationships for all three antimicrobials, indicating that the summation of all dissipation processes for each antimicrobial could be described by first-order kinetics. The slopes of the three plots were significantly different, indicating that the order of dissipation was lincomycin < sulfamethazine < chlortetracycline. Consequently, the dissipation DT50 (time required for 50% antimicrobial dissipation) values for lincomycin (14.0 d), sulfamethazine (7.0 d), and chlortetracycline (3.3 d) were significantly different. The longer DT50 values of lincomycin and sulfamethazine suggest that environmentally relevant concentrations of these antimicrobials may affect bacterial production in prairie wetlands.


Assuntos
Anti-Infecciosos , Clortetraciclina , Canadá , Ecossistema , Pradaria , Lincomicina , Sulfametazina , Áreas Alagadas
6.
J Environ Qual ; 49(3): 582-592, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016386

RESUMO

We developed a GIS-based tool that values, in a spatially explicit way, the ecosystem services generated by water quality improvements resulting from adoption of agricultural best management practices (BMPs). The tool is calibrated for watersheds in the Chesapeake Bay drainage and includes the benefits from water quality improvements within targeted watersheds, water quality improvements downstream from targeted watersheds, and reductions in pollutant loadings to Chesapeake Bay. The tool is used to investigate specific BMP scenarios adopted within specific watersheds. The results show that (i) BMP adoption generates large positive net benefits to society, with benefit/cost ratios ranging from 22 to 276; (ii) by selecting cost effective BMPs and placing them in the most appropriate places, the cost of meeting pollutant reduction targets would be reduced by 34-71%; and (iii) net benefits from BMP adoption are higher when they are implemented close to or upstream from population centers.


Assuntos
Ecossistema , Qualidade da Água , Agricultura , Água , Abastecimento de Água
7.
J Environ Qual ; 49(3): 569-581, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016400

RESUMO

Urbanization alters the delivery of water and sediment to receiving streams, often leading to channel erosion and enlargement, which increases loading of sediment and nutrients, degrades habitat, and harms sensitive biota. Stormwater control measures (SCMs) are constructed in an attempt to mitigate some of these effects. In addition, stream restoration practices such as bank stabilization are increasingly promoted as a means of improving water quality by reducing downstream sediment and pollutant loading. Each unique combination of SCMs and stream restoration practices results in a novel hydrologic regime and set of geomorphic characteristics that interact to determine stream condition, but in practice, implementation is rarely coordinated due to funding and other constraints. In this study, we examine links between watershed-scale implementation of SCMs and stream restoration in Big Dry Creek, a suburban watershed in the Front Range of northern Colorado. We combine continuous hydrologic model simulations of watershed-scale response to SCM design scenarios with channel evolution modeling to examine interactions between stormwater management and stream restoration strategies for reducing loading of sediment and adsorbed phosphorus from channel erosion. Modeling results indicate that integrated design of SCMs and stream restoration interventions can result in synergistic reductions in pollutant loading. Not only do piecemeal and disunited approaches to stormwater management and stream restoration miss these synergistic benefits, they make restoration projects more prone to failure, wasting valuable resources for pollutant reduction. We conclude with a set of recommendations for integrated planning of SCMs and stream restoration to simultaneously achieve water quality and channel protection goals.


Assuntos
Conservação dos Recursos Naturais , Qualidade da Água , Colorado , Ecossistema , Chuva
8.
J Environ Qual ; 49(3): 688-699, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016403

RESUMO

Ecosystem reconstruction after mining disturbance is a challenge considering the multitude of factors that affect soil formation and revegetation. In the boreal forest of western Canada, peat material is often used as the organic amendment for land reclamation to upland forest. Carbon and water dynamics of peat-dominated ecosystems differ from natural upland forest soils. The objective of this work was to evaluate the evolution of soils reconstructed after mining disturbance using 13 C and 2 H analyses of n-alkane tracers. Ten soils from natural ecosystems were sampled (0-10 cm) and compared with 11 soils from novel ecosystems ranging in age from 0 to 30 yr, as well as a fresh peat sample. Soils supported different vegetation, including pine (Pinus spp.), aspen (Populus spp.), and white spruce [Picea glauca (Moench) Voss]. Despite overlaps for some individual n-alkanes, we found a dominance of n-C25 in reconstructed soils, also dominant in the peat material, and a dominance of n-C27 in natural soils, one of the dominant n-alkanes in natural forest vegetation. In addition, there was a significant difference in odd n-alkane δ2 H and δ13 C values between natural and reconstructed soils (p < .05). Differences in δ2 H values, more negative for reconstructed soils than for natural soils, were attributed to changes in soil moisture, from wetter peat-dominated soils to drier upland forests; among forest types, δ2 H values were most negative under pine vegetation. The δ13 C composition of odd n-alkanes, in particular n-C27 , was significantly related to tree age (p < .05). Overall, both 2 H and 13 C isotopic signatures of odd n-alkanes exhibited differences between natural and reconstructed soils. However, within the reconstructed soils, neither isotopic signature showed a clear evolution with age since reclamation.


Assuntos
Carbono , Solo , Alcanos , Canadá , Ecossistema , Hidrogênio , Isótopos
9.
J Environ Qual ; 49(2): 314-323, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016430

RESUMO

Soil freeze-thaw cycles (FTCs) profoundly influence biophysical conditions and modify biogeochemical processes across many northern-hemisphere and alpine ecosystems. How FTCs will contribute to global processes in seasonally snow-covered ecosystems in the future is of particular importance as climate change progresses and winter snowpacks decline. Our understanding of these contributions is limited because there has been little consideration of inter- and intrayear variability in the characteristics of FTCs, in part due to a limited appreciation for which of these characteristics matters most with respect to a given biogeochemical process. Here, we introduce the concept of effective FTCs: those that are most likely linked to changes in key soil processes. We also propose a set of parameters to quantify and characterize effective FTCs using standard field soil temperature data. To put these proposed parameters into effective practice, we present FTCQuant, an R package of functions that quantifies FTCs based on a set of user-defined parameter criteria and, importantly, summarizes the individual characteristics of each FTC counted. To demonstrate the utility of these new concepts and tools, we applied the FTCQuant package to re-analyze data from two published studies to help explain over-winter changes to N2 O emissions and wet-aggregate stability. We found that effective FTCs would be defined differently for each of these response variables and that effective FTCs provided a 76 and 33% increase in model fit for wet-aggregate stability and cumulative N2 O emission, respectively, relative to conventional FTC quantification methods focusing on fluctuations around 0 °C. These results demonstrate the importance of identifying effective FTCs when scaling soil processes to regional or global levels. We hope our contributions will inform future deductions, hypothesis generation, and experimentation with respect to expected changes in freeze-thaw cycling globally.


Assuntos
Ecossistema , Solo , Mudança Climática , Congelamento , Neve
10.
J Environ Qual ; 49(2): 404-416, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016431

RESUMO

Biogeochemical processes in northern peatland ecosystems are influenced by seasonal temperature fluctuations that are changing with the climate. Methylmercury (MeHg), commonly produced in peatlands, affects downstream waters; therefore, it is important to understand how temperature transitions affect mercury (Hg) dynamics. We investigated how the freeze-thaw cycle influences belowground peat pore water total Hg (THg), MeHg, and dissolved organic carbon (DOC). Four large, intact peat columns were removed from an ombrotrophic peat bog and experimentally frozen and thawed. Pore water was sampled across seven depths in the peat columns during the freeze-thaw cycle and analyzed for THg, MeHg, and DOC concentrations. Freezing results showed increased concentrations of THg below the ice layers and limited change in MeHg concentrations. During thawing, THg concentrations significantly increased, whereas MeHg concentrations decreased. Limited bromide movement and depth decreases in THg and DOC concentrations were associated with increased bulk density and degree of humification in the peat. The experiment demonstrates the effects of the freeze-thaw cycle on Hg concentrations in northern peatlands. Changes to freeze-thaw cycles with climate change may exacerbate Hg cycling and transport processes in peatland environments.


Assuntos
Mercúrio/análise , Compostos de Metilmercúrio , Ecossistema , Congelamento , Solo
11.
J Environ Qual ; 49(5): 1081-1091, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016440

RESUMO

Terrestrial ecosystems, both natural ecosystems and agroecosystems, generate greenhouse gases (GHGs). The chamber method is the most common method to quantify GHG fluxes from soil-plant systems and to better understand factors affecting their generation and mitigation. The objective of this study was to review and synthesize literature on chamber designs (non-flow-through, non-steady-state chamber) and associated factors that affect GHG nitrous oxide (N2 O) flux measurement when using chamber methods. Chamber design requires consideration of many facets that include materials, insulation, sealing, venting, depth of placement, and the need to maintain plant growth and activity. Final designs should be tailored, and bench tested, in order to meet the nuances of the experimental objectives and the ecosystem under study while reducing potential artifacts. Good insulation, to prevent temperature fluctuations and pressure changes, and a high-quality seal between base and chamber are essential. Elimination of pressure differentials between headspace and atmosphere through venting should be performed, and designs now exist to eliminate Venturi effects of earlier tube-type vent designs. The use of fans within the chamber headspace increases measurement precision but may alter the flux. To establish best practice recommendations when using fans, further data are required, particularly in systems containing tall plants, to systematically evaluate the effects that fan speed, position, and mixing rate have on soil gas flux.


Assuntos
Ecossistema , Metano/análise , Dióxido de Carbono/análise , Monitoramento Ambiental , Óxido Nitroso/análise
12.
J Environ Qual ; 49(5): 1322-1333, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016441

RESUMO

Antibiotics and estrogens are recognized as emerging contaminants in the water environment because of their potentially adverse effects on aquatic ecosystems. The concentrations of four steroid estrogens (17α-estradiol, 17ß-estradiol, estrone, and estriol) and eight antibiotics (norfloxacin, levofloxacin, ciprofloxacin, enrofloxacin, metronidazole, sulfapyridine, doxycycline, and sulfamethoxazole) in the Chaohu Lake basin in Anhui province, China, were analyzed along with adjacent wastewater. The levels of the target antibiotics and estrogens were below detection limits (not detected [nd])-89.86 and nd-118.09 ng L-1 , respectively, in the lake water. All of the target antibiotics and estrogens were detected in sediment, and the concentrations ranged widely (nd-35,544 and nd-16,344 ng kg-1 , respectively). Antibiotics and estrogens varied spatially in the study area and mostly came from untreated wastewater. Antibiotics and estrogens were associated with water parameters such as pH and total nitrogen. A significant positive correlation was observed between estriol and levofloxacin concentrations (r = .65; p < .01), indicating that levofloxacin from the same source might have inhibited the microbiological degradation of estriol in the surface water. Overall, the estrogens pose a more severe risk than antibiotics to the Chaohu Lake system. However, co-occurrence of antibiotics may affect the fate of estrogens in the same lake media. More attention should be given to estrogens than to antibiotics in wastewater-affected lake systems.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Antibacterianos/análise , China , Ecossistema , Monitoramento Ambiental , Estrogênios/análise , Lagos/análise
13.
J Environ Qual ; 49(5): 1435-1444, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016451

RESUMO

Chlortetracycline (CTC), an antimicrobial administered as a feed additive to cattle, swine, and poultry, is present in the corresponding manure. Land application of raw or processed (composted or stockpiled) manure provides a mechanism by which CTC (and other antimicrobials) enters the environment and becomes available for transport to surface receiving waters via rainfall or snowmelt runoff. Chlortetracycline has been detected in Canadian surface waters, but little has been reported on its fate in aquatic ecosystems. To address this knowledge gap, the dissipation of CTC-enol was monitored in deionized water and water typical of wetlands within the prairie region of Canada. In deionized water, CTC-enol tautomerized to CTC-keto, and both tautomers epimerized to 4-epi-CTC-enol and 4-epi-CTC-keto, respectively. Irreversible isomerization to iso-CTC occurred, which then epimerized to 4-epi-iso-CTC. In wetland water, although tauterization of CTC-enol to CTC-keto occurred, there was no evidence of the formation of the 4-epimers of either CTC-enol or CTC-keto. The major product formed in the wetland water was iso-CTC, some of which epimerized to 4-epi-iso-CTC. Although CTC-enol was shown to tautomerize to CTC-keto, the concentration of CTC-keto remained low in both deionized and wetland water, suggesting that the isomerization of CTC-enol to iso-CTC most likely occurred via CTC-keto. The dissipation of CTC-enol in wetland water was described by pseudo first-order kinetics with a DT50 (time required for 50% dissipation) value of 4.8 h. The short DT50 value of CTC and reduced antimicrobial activity of iso-CTC and 4-epi-iso-CTC suggest a lower probability for selection for CTC-resistant bacteria in Canadian Prairie aquatic ecosystems.


Assuntos
Clortetraciclina , Animais , Canadá , Bovinos , Ecossistema , Pradaria , Isomerismo , Suínos , Áreas Alagadas
14.
J Environ Qual ; 49(4): 793-811, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016486

RESUMO

This review examines the impact of prescribed fire on the water quality variables (a) sediment load and (b) limiting macronutrients in forested environments globally. We aim to characterize the forested environments subject to prescribed fire, to discuss factors of the fire regime that contribute to water quality concerns, and to offer insight into the effect of precipitation timing and study scale on constituent exports. High fuel consumption during fire increases the risk of erosion and constituent export during precipitation, though high fuel consumption during prescribed fire is uncommon in forested environments. Small-scale studies examining sediment yield after prescribed fire may fail to capture the effect of landscape-scale spatial variability, and watershed-scale studies accounting for such variability are lacking. Although small-plot studies confirm that prescribed fire can alter hydrologic inputs, the environmental impact of these increases is minimal, particularly when compared with other land-use systems. Generally, prescribed fire is a beneficial and low-impact disturbance that likely improves fire-adapted forest health. However, gaps in knowledge exist at various spatial and temporal scales; this review suggests two avenues of future research, including (a) greater understanding of fire regime interactions that control surface runoff and erosion at the watershed scale, and (b) monitoring forest health and ecological function after prescribed fire rather than direct nutrient exports.


Assuntos
Ecossistema , Fogo , Florestas , Nutrientes , Qualidade da Água
15.
J Environ Qual ; 49(4): 961-972, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016495

RESUMO

The effects of enhanced acid deposition from the atmosphere, and associated elevated inputs of N, are widely evident, especially for forests where excess N has led to a variety of deleterious effects. These include declines in biodiversity, a response that will likely require considerable time for recovery. The purpose of this study was to determine responses of plant nutrient availability in surface mineral soil to 25 yr of experimental acidification and N addition in a central Appalachian hardwood forest ecosystem. We hypothesized that chronic additions of (NH4 )2 SO4 will increase mineral N, decrease soil pH, P, and base cations, increase micronutrients (Mn2+ and Fe2+ ), and increase levels of Al3+ . Results supported these predictions, although Mn2+ did not vary significantly. Earlier work on these plots found no response of any of the extractable nutrients to 3 yr of treatment, yet after 25 yr, our results suggest that impacts are apparent in the top 5 cm of the A horizon. We surmise that impacts in these soils may have lagged behind the onset of acidification treatments or that several years of treatment were required to overcome preexisting differences in soil ions. Generally, current findings confirm that (NH4 )2 SO4 treatments have lowered the pH, enhanced levels of exchangeable Al3+ , and increased stream-water exports of NO3 - and base cations-a process that further acidifies soil. The combination of these changes in surface soils, with their high proportion of fine roots, may contribute to the reduced growth and competitiveness of some hardwood species at the acidified site.


Assuntos
Ecossistema , Solo , Região dos Apalaches , Florestas , Concentração de Íons de Hidrogênio
16.
Environ Monit Assess ; 192(10): 666, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33001295

RESUMO

Knowledge of the background activity concentrations of anthropogenic radionuclides before the start of operation of the new nuclear power plant in Belarus, BelNPP, is an issue of great importance for neighbouring countries. In this study, we provide the pilot characterisation of the Lithuanian part of the 30-km zone of the BelNPP, emphasising the forest plants, terrestrial mosses, forest organic and mineral topsoil to describe the preoperational radioecological state of the pine forest ecosystem. Key anthropogenic radionuclides (14C, 3H, 137Cs and 239,240Pu) were analysed. The 14C specific activity varied from 97.80 ± 1.30 to 102.40 ± 0.79 pMC. The 3H specific activity in the tissue-free water tritium form varied from 13.2 ± 2.2 TU to 20.8 ± 2.3 TU, which corresponded to the 3H level of precipitation in this region. The activity concentrations of 239,240Pu in soil and moss samples did not exceed 1 Bq/kg and were mainly due to global fallout after nuclear tests. The 137Cs inventory in the pine forest soils of the Lithuanian part of the BelNPP 30-km zone varied from 930 ± 70 to 1650 ± 430 Bq/m2. High variation of the inventory and uneven distribution in the soil profile conditioned a wide range of 137Сs activity in terrestrial plants from 1.0 ± 0.5 to 40.5 ± 1.8 Bq/kg dry weight. The abundance of microorganisms in different seasons and soil depths do not exceed the natural levels. According to PCA loads, the number of microorganisms and variability of 137Cs specific activity is determined by soil abiotic parameters.


Assuntos
Centrais Nucleares , Poluentes Radioativos do Solo/análise , Ecossistema , Monitoramento Ambiental , Florestas , Solo
17.
Environ Monit Assess ; 192(11): 685, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33026535

RESUMO

The Anzali wetland (located in northern Iran) and many parts of its catchment are considered important habitats for the swan mussel (Anodonta cygnea). The habitat of this native bioindicator mussel is being threatened in many locations of the catchment due to various anthropogenic activities. The present study aimed to apply a classification tree model (J48 algorithm) to predict the habitat preferences of A. cygnea in 12 sampling sites based on various water quality and physical-habitat variables. The species was present in 50% of sampling sites, while it was absent in the remaining of the sampling sites. In total, 144 samples of A. cygnea (72 presence and 72 absence instances) were monthly measured together with the abiotic variables during 1-year study period (2017-2018). For the CT model, two-thirds of datasets (96 instances) served as a training and the remainder was employed for the validation set (48 instances). Among 25 environmental variables introduced to the model (with pruning confidence factor = 0.10, threefold cross-validation and 5 times randomization effort), the validity of 6 variables was confirmed by the model in all three subsets. Water salinity, flow velocity, water depth and water turbidity were jointly predicted by the model in three subsets. The model predicted that the absence of A. cygnea might be associated with increasing flow velocity, total phosphate and water turbidity. In contrast, the presence of A. cygnea might be related to decreased water depth and increased calcium concentration. The model also confirmed that all predicted variables for the species might be completely dependent on the water salinity. According to the chi-square test (x2 = 26.53, p < 0.05), the habitat condition of A. cygnea is influenced by significant variations in the spatio-temporal patterns.


Assuntos
Anodonta , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Irã (Geográfico) , Poluentes Químicos da Água/análise
18.
Artigo em Inglês | MEDLINE | ID: mdl-33013700

RESUMO

The origin of the coronavirus disease 2019 (COVID-19) pandemic is zoonotic. The circadian day-night is the rhythmic clue to organisms for their synchronized body functions. The "development for mankind" escalated the use of artificial light at night (ALAN). In this article, we tried to focus on the possible influence of this anthropogenic factor in human coronavirus (HCoV) outbreak. The relationship between the occurrences of coronavirus and the ascending curve of the night-light has also been delivered. The ALAN influences the physiology and behavior of bat, a known nocturnal natural reservoir of many Coronaviridae. The "threatened" and "endangered" status of the majority of bat species is mainly because of the destruction of their proper habit and habitat predominantly through artificial illumination. The stress exerted by ALAN leads to the impaired body functions, especially endocrine, immune, genomic integration, and overall rhythm features of different physiological variables and behaviors in nocturnal animals. Night-light disturbs "virus-host" synchronization and may lead to mutation in the genomic part of the virus and excessive virus shedding. We also proposed some future strategies to mitigate the repercussions of ALAN and for the protection of the living system in the earth as well.


Assuntos
Quirópteros/fisiologia , Infecções por Coronavirus/epidemiologia , Iluminação , Pneumonia Viral/epidemiologia , Animais , Ecossistema , Meio Ambiente , Humanos , Luz , Melatonina/fisiologia , Pandemias
19.
Environ Monit Assess ; 192(11): 701, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33051711

RESUMO

Investigating the spatiotemporal trends and trade-off/synergy relationships among ecosystem services can provide effective support for urban planning and decision making toward sustainable development. With Nanjing city in China as a case study, this study assessed the spatiotemporal dynamics of six key ecosystem services from 2005 to 2030. Integration of Markov-cellular automata and ecosystem services models was realized to analyze the potential impacts of future urbanization on ecosystem services by simulating business-as-usual (BAU), cropland protection (CP), and ecological restoration (ER) scenarios. Furthermore, an innovative trade-off/synergy degree was developed to quantify the magnitude of the complex relationship among the multiple ecosystem services under the different scenarios. Due to the rapid expansion of built-up land, carbon storage, habitat quality, and air purification decreased 2.92%, 5.80%, and 7.91%, respectively. The CP scenario exhibited the highest crop production values, and the ER scenario was a better urban development strategy that enhanced the regulating ecosystem services at the expense of crop production. To promote urban ecosystem services and minimize trade-offs, we proposed certain future urban development strategies, including ecological corridor construction and compact development. The study could provide a scientific reference for the effective ecosystem management of Nanjing and other rapidly urbanized regions.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , China , Cidades , Monitoramento Ambiental
20.
J Environ Qual ; 49(3): 593-602, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016395

RESUMO

Emerging technologies and practices allow wastewater treatment facilities to recover valuable resources such as nutrients, energy, and recycled water during the wastewater treatment process. The ability to recover resources from wastewater introduces new tradeoffs in both water quality and quantity management. In particular, the fact that communities can obtain revenue from the sale of resources that are recovered from wastewater may help internalize the externalities of insufficient wastewater treatment. In this paper, we develop a theoretical model to characterize these tradeoffs within a hydroeconomic framework of optimal wastewater treatment with resource recovery, which is particularly well suited for applications in nutrient management. We use this model to derive analytical results that describe the economically optimal level of deployment, accounting for the fact that the technology or practice is costly and it generates benefits in the form of revenue from the recovered resource, as well as other societal benefits, such as improvements in human and ecosystem health. In addition, we present two examples using specific functional forms for treatment costs to demonstrate how the model can be applied to obtain general principles regarding societally optimal deployment. Our hydroeconomic framework can be used to explore the socioeconomic implications of strategies that target deployment of wastewater treatment with resource recovery, especially nutrients, at multiple scales.


Assuntos
Águas Residuárias , Purificação da Água , Ecossistema , Humanos , Eliminação de Resíduos Líquidos , Qualidade da Água
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