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541.
Emerging Tools for Continuous Nutrient Monitoring Networks: Sensors Advancing Science and Water Resources Protection 下载免费PDF全文
Brian A. Pellerin Beth A. Stauffer Dwane A. Young Daniel J. Sullivan Suzanne B. Bricker Mark R. Walbridge Gerard A. Clyde Jr. Denice M. Shaw 《Journal of the American Water Resources Association》2016,52(4):993-1008
Sensors and enabling technologies are becoming increasingly important tools for water quality monitoring and associated water resource management decisions. In particular, nutrient sensors are of interest because of the well‐known adverse effects of nutrient enrichment on coastal hypoxia, harmful algal blooms, and impacts to human health. Accurate and timely information on nutrient concentrations and loads is integral to strategies designed to minimize risk to humans and manage the underlying drivers of water quality impairment. Using nitrate sensors as the primary example, we highlight the types of applications in freshwater and coastal environments that are likely to benefit from continuous, real‐time nutrient data. The concurrent emergence of new tools to integrate, manage, and share large datasets is critical to the successful use of nutrient sensors and has made it possible for the field of continuous monitoring to rapidly move forward. We highlight several near‐term opportunities for federal agencies, as well as the broader scientific and management community, that will help accelerate sensor development, build and leverage sites within a national network, and develop open data standards and data management protocols that are key to realizing the benefits of a large‐scale, integrated monitoring network. Investing in these opportunities will provide new information to guide management and policies designed to protect and restore our nation's water resources. 相似文献
542.
浅谈我国推行排污许可制度难点及对策 总被引:2,自引:2,他引:0
我国排污许可制度推行已有二十余年,但由于在政策设计层面、技术支撑层面及配套保障层面尚有不足之处,排污许可制度在推行过程中遇到很多阻碍,排污许可制度的应用范围、实施效果和改革举措实际落地都还不尽如人意,依然处于难以推广的境地。本文基于对以上各层面存在问题的深入分析,进而指出目前阻碍排污许可制度推行的难点问题及具体成因,其中难点问题主要包括专项法律法规缺失、管理要求落地难、各方权责落实难、多套数据并行、排放标准滞后、部分行业标准缺失、与环境目标未建立响应关系、管理方式落后、数据支撑和人员配备不足等方面。根据前述问题的论证,本文相应提出了推进排污许可制度改革的各项对策措施,并建议排污许可制度应形成上下联动的工作格局,进一步夯实技术支撑基础和完善配套保障措施,以期助力排污许可制度各项改革举措的实际落地,更好地推进排污许可制度的有效实施,建立系统完整、权责清晰、监管有效的管理格局,最终实现排污许可"一证式"管理模式。 相似文献
543.
F. Bouhamed Z. Elouear J. Bouzid B. Ouddane 《Environmental science and pollution research international》2016,23(16):15801-15806
The removal of Cu2+, Ni2+, and Zn2+ ions from their multi-component aqueous mixture by sorption on activated carbon prepared from date stones was investigated. In the batch tests, experimental parameters were studied, including solution pH, contact time, initial metal ions concentration, and temperature. Adsorption efficiency of the heavy metals was pH-dependent and the maximum adsorption was found to occur at around 5.5 for Cu, Zn, and Ni. The maximum sorption capacities calculated by applying the Langmuir isotherm were 18.68 mg/g for Cu, 16.12 mg/g for Ni, and 12.19 mg/g for Zn. The competitive adsorption studies showed that the adsorption affinity order of the three heavy metals was Cu2+?>?Ni2+?>?Zn2+. The test results using real wastewater indicated that the prepared activated carbon could be used as a cheap adsorbent for the removal of heavy metals in aqueous solutions. 相似文献
544.
Jianxin Shou Huaping Dong Jianfa Li Jiaxing Zhong Saijun Li Jinhong Lü Yimin Li 《Environmental science and pollution research international》2016,23(19):19156-19163
Biochars’ properties will change after application in soil due to the interactions with soil constituents, which would then impact the performance of biochars as soil amendment. For a better understanding on these interactions, two woody biochars of different surface areas (SA) were physically treated with aluminum oxide (Al-oxide) to investigate its potential influence on biochars’ sorption property. Both the micropore area and mesopore (17~500 Å in diameter) area of the low-SA biochar were enhanced by at least 1.5 times after treatment with Al-oxide, whereas the same treatment did not change the surface characteristics of the high-SA biochar due partly to its well-developed porosity. The enhanced sorption of the pesticide isoproturon to the Al-oxide-treated low-SA biochar was observed and is positively related to the increased mesopore area. The desorption hysteresis of pesticide from the low-SA biochar was strengthened because of more pesticide molecules entrapped in the expanded pores by Al-oxide. However, no obvious change of pesticide sorption to the high-SA biochar after Al-oxide treatment was observed, corresponding to its unchanged porosity. The results suggest that the influence of Al-oxide on the biochars’ sorption property is dependent on their porosity. This study will provide valuable information on the use of biochars for reducing the bioavailability of pesticides. 相似文献
545.
ZhiYing Yan XiuLi Wei YueXiang Yuan ZhiDong Li Dong Li XiuFeng Liu 《Journal of the Air & Waste Management Association (1995)》2016,66(4):420-428
Odor pollution is a big environmental problem caused by large-scale livestock production in China, and developing a practical way to reduce these odors is pressing. In this study, a combination of 0.2–1.0 U/mL lignin peroxidase (LiP) and one of three peroxides (H2O2, CaO2, 2Na3CO3·3H2O2) was examined for its efficiency in reducing the release of eight chemicals (propionic acid, isobutyric acid, isocaproic acid, isovaleric acid, phenol, p-cresol, indole, and skatole), NH3, H2S, and odor intensity from pig manure. The results showed an approximately 90% reduction in p-cresol, 40–60% reduction in odor intensity, 16.5–40% reduction in indolic compounds, and 25–40% reduction in volatile fatty acids. Being the electron acceptors of LiP, 2Na3CO3·3H2O2 and CaO2 performed better than H2O2 in reducing the concentration of eight chemicals, NH3, H2S, and odor intensity from pig manure. The effect of deodorization can last for up to 72 hr.
Implications: In China, one of the major environmental problems caused by confined feeding is odor pollution, which brings a major threat to the sustainability, profitability, and growth of the livestock industry. To couple the LiP with the electron acceptors, a low–cost, simple, and feasible method for odor removal was established in this study. Based on the study results, a practical treatment method was provided for odor pollution and supply the farm operators a more flexible time to dispose treated manure. 相似文献
546.
Eomecon chionantha Hance, the only species in the genus Eomecon, is an angiosperm species endemic to China. Here we investigated the pollination syndrome, pollinator generalization of E. chionantha. Our results showed that the individual flower longevity of E. chionantha was 3–5 days. The flowering phenology of E. chionantha can be divided into five phases. We found significant differences in the pollination efficiency of the different insects visiting E. chionantha with bees and flies being the most efficient pollinators. This, in addition to floral morphology and phenology, suggests that E. chionantha is generalized on bees and flies and possesses an outcrossing, partially self-compatible and pollinator-dependent breeding system. 相似文献
547.
L. P. Agulova N. S. Moskvitina N. P. Bol’shakova L. B. Kravchenko N. V. Ivanova V. N. Romanenko 《Russian Journal of Ecology》2016,47(5):460-466
The dynamics and correlations of ecophysiological parameters have been studied in two spatially separated multispecies communities of murine rodents and ixodid tick larvae and nymphs that parasitize them. It has been shown that all the processes under consideration have nonstationary, oscillatory dynamics. The long-term dynamics of connectivity of ecophysiological characteristics within communities and their synchronization by weather–climatic factors are, by nature, wavelike processes of transitions between the states with stronger and weaker linkage between parameters, which, along with nonstationarity, can contribute to the maintenance of stability and integrity of communities. 相似文献
548.
Kerns Becky K. Kim John B. Kline Jeffrey D. Day Michelle A. 《Regional Environmental Change》2016,16(7):2129-2140
Regional Environmental Change - We examined landscape exposure to wildfire potential, insects and disease risk, and urban and exurban development for the conterminous US (CONUS). Our analysis... 相似文献
549.
Thomas M. Lewinsohn José Luiz Attayde Carlos Roberto Fonseca Gislene Ganade Leonardo Ré Jorge Johannes Kollmann Gerhard E. Overbeck Paulo Inácio Prado Valério D. Pillar Daniela Popp Pedro L. B. da Rocha Wesley Rodrigues Silva Annette Spiekermann Wolfgang W. Weisser 《Ambio》2015,44(2):154-162
Ecological science contributes to solving a broad range of environmental problems. However, lack of ecological literacy in practice often limits application of this knowledge. In this paper, we highlight a critical but often overlooked demand on ecological literacy: to enable professionals of various careers to apply scientific knowledge when faced with environmental problems. Current university courses on ecology often fail to persuade students that ecological science provides important tools for environmental problem solving. We propose problem-based learning to improve the understanding of ecological science and its usefulness for real-world environmental issues that professionals in careers as diverse as engineering, public health, architecture, social sciences, or management will address. Courses should set clear learning objectives for cognitive skills they expect students to acquire. Thus, professionals in different fields will be enabled to improve environmental decision-making processes and to participate effectively in multidisciplinary work groups charged with tackling environmental issues. 相似文献
550.
农业面源污染是水体中COD、氮、磷等指标的主要来源。它包括农药化肥施用、畜禽养殖和农村生活污水排放。对农业源水污染物进行削减是实现污染物总量控制的重要手段。通过详细总结国内外现有农业源水污染物削减技术方法,分析对比其优缺点和实用性,筛选出适用于不同农业污染来源的污水处理技术。结果表明,畜禽养殖废水的适宜处理技术有厌氧/缺氧/好氧(A/A/O)、序批式活性污泥法(SBR)、膜生物反应器(MBR)、升流式厌氧污泥床(UASB)、厌氧沼气池;农地施肥污水的适宜处理技术有SBR、MBR、UASB;农村生活污水的适宜处理技术有厌氧沼气池、生物滴滤池、人工湿地、稳定塘。 相似文献