Mowers versus growers: Riparian buffer management in the Southern Blue Ridge Mountains,USA

Despite long-standing knowledge of the benefits of riparian buffers for mitigating nonpoint source pollution, many streams are unprotected by buffers. Even landowners who understand ecological values of buffers mow riparian vegetation to the streambank. Do trends in rural riparian conditions reflect the development of riparian forest science? What motivates residential riparian management actions? Using high-resolution orthoimagery, we quantified riparian conditions and trends between 1998 and 2015 in the rural upper Little Tennessee River basin in Macon County, North Carolina and explored how landowners view riparian zone management and riparian restoration programs. Buffer composition in 2015 was as follows: no buffer (32.5%), narrow (19.3%), forested (26.7%), shrub (7.2%), and intermediate (7.0%). Relative to 1998, the greatest decrease occurred in the no buffer class (−17.7%, 46 km) and the largest increases occurred in the shrub (+72.5%, 20 km) and narrow (12.6%, 14 km) classes. Forested buffer marginally increased. Semi-structured interview data suggest that landowners prioritize recreational and scenic aspects of riparian buffers over ecological functions such as filtration and bank stabilization. Riparian restoration programs might be made more enticing to non-adopters if outreach language appealed to landowner priorities, design elements demonstrated intentional management, and program managers highlighted areas where ecological goals and landowner values align.     

The value of virtual conferencing for ecology and conservation

The objectives of conservation science and dissemination of its research create a paradox: Conservation is about preserving the environment, yet scientists spread this message at conferences with heavy carbon footprints. Ecology and conservation science depend on global knowledge exchange—getting the best science to the places it is most needed. However, conference attendance from developed countries typically outweighs that from developing countries that are biodiversity and conservation hotspots. If any branch of science should be trying to maximize participation while minimizing carbon emissions, it is conservation. Virtual conferencing is common in other disciplines, such as education and humanities, but it is surprisingly underused in ecology and conservation. Adopting virtual conferencing entails a number of challenges, including logistics and unified acceptance, which we argue can be overcome through planning and technology. We examined 4 conference models: a pure‐virtual model and 3 hybrid hub‐and‐node models, where hubs stream content to local nodes. These models collectively aim to mitigate the logistical and administrative challenges of global knowledge transfer. Embracing virtual conferencing addresses 2 essential prerequisites of modern conferences: lowering carbon emissions and increasing accessibility for remote, time‐ and resource‐poor researchers, particularly those from developing countries.     

Research on Methods for Building Volcano Disaster Information System--taking Changbai Mountain as an example

1IntroductionAs a many-volcano-distributed country,China is covered with many volcanoes and lava rocks.A-mong the one-thousand-or-so volcanoes,Changbai Mountain Volcano,Wudalianchi Volcano,Tengchong Volcano and Ashikule Volcano of West Kunlun are the mostlatentcatastrophic erup-tive active volcanoes.In recent years,the activity of the earth' s crust in some volcanic areas isobviously becoming increasing violent.Butfew scholars have monitored and evaluated volcano inChina.So building VDI…     

广州市环境监测管理信息化建设中若干问题探讨

以广州市环境监测中心站推进信息化的实践为例，重点对环境监测管理信息化规划、开发和应用3个环节所涉及的信息化进程路线、应用系统开发的需求分析和推广应用等问题进行了一些探讨，提出切合自身的解决思路或办法。     

Combined Effects of Levels of Protection and Environmental Variables at Different Spatial Resolutions on Fish Assemblages in a Marine Protected Area

Abstract: The links between species–environment relations and species’ responses to protection are unclear, but the objectives of marine protected areas (MPAs) are most likely to be achieved when those relations are known and inform MPA design. The components of a species’ habitat vary with the spatial resolution of the area considered. We characterized areas at two resolutions: 250 m² (transect) and approximately 30,000 m² (seascape). We considered three categories of environmental variables: substrate type, bottom complexity, and depth. We sought to determine at which resolution habitat characteristics were a better predictor of abundance and species composition of fishes and whether the relations with environmental variables at either resolution affected species’ responses to protection. Habitat features accounted for a larger proportion of spatial variation in species composition and abundances than differences in protection status. This spatial variation was explained best by habitat characteristics at the seascape level than at the transect level. Species’ responses to protected areas were specific to particular seascape characteristics, primarily depth, and bottom complexity. Our method may be useful for prioritizing marine areas for protection, designing MPAs, and monitoring their effectiveness. It identified areas that provided natural shelter, areas acting as buffer zones, and areas where fish species were most responsive to protection. The identification of such areas is necessary for cost‐effective establishment and monitoring of MPAs.     

锆-十六烷基三甲基氯化铵改性活性炭对水中硝酸盐和磷酸盐的吸附特性

采用锆(Zr)和阳离子表面活性剂十六烷基三甲基氯化铵(CTAC)对活性炭进行联合改性,考察了所制备的Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐的吸附去除作用,并探讨了相关的吸附去除机制.结果表明,Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐均具备较好的吸附去除能力.Zr-CTAC改性活性炭对硝酸盐和磷酸盐吸附动力学过程满足准二级动力学模型.Langmuir、Freundlich和Dubinin-Radushkevich(D-R)等温吸附模型可以较好地描述Zr-CTAC改性活性炭对水中硝酸盐的等温吸附过程,Langmuir和D-R等温吸附模型可以较好地描述Zr-CTAC改性活性炭对水中磷酸盐等温吸附过程,通过Langmuir模型计算得到吸附剂对硝酸盐和磷酸盐的最大单位吸附量分别为7.58 mg·g-1和10.9 mg·g-1.高的p H会抑制Zr-CTAC改性活性炭对水中硝酸盐和磷酸盐的吸附.水中共存的Cl-、HCO-3和SO2-4等阴离子均会抑制Zr-CTAC改性活性炭对硝酸盐和磷酸盐的吸附,且对吸附硝酸盐的抑制作用较强而对吸附磷酸盐的抑制作用较弱.水中共存的磷酸盐对Zr-CTAC改性活性炭吸附硝酸盐的抑制作用较强,而水中共存的硝酸盐对Zr-CTAC改性活性炭吸附磷酸盐的抑制作用较弱.1 mol·L-1Na Cl溶液可以使90%左右被吸附到Zr-CTAC改性活性炭表面上的硝酸盐解吸下来.1 mol·L-1的Na OH溶液可以使78%左右被吸附到Zr-CTAC改性活性炭表面上的磷酸盐解吸下来.Zr-CTAC改性活性炭对硝酸盐的吸附机制主要包括阴离子交换作用和静电吸引作用,对磷酸盐的吸附机制主要包括配位体交换作用、阴离子交换作用和静电吸引作用.上述结果说明Zr-CTAC改性活性炭适合作为一种吸附剂去除废水中的硝酸盐和磷酸盐.     

SBR加载不同粒径磁性活性炭对其污泥颗粒化进程的影响机制

在相同序批式活性污泥反应器(SBR)中分别加载1.5 g·L~(-1)的80、140、200、和300目不同粒径的磁性活性炭(反应器编号依次为2、3、4、5号),同时以不投加磁性活性炭的SBR反应器(1号)作为对照组,研究各反应器污泥体积指数(SVI)、粒径分布特征、胞外聚合物(EPS)中胞外蛋白(PN)、胞外多糖(PS)的含量变化规律以及除污性能.结果表明,不同粒径磁性活性炭对污泥颗粒化进程有一定的影响,粒径过大、过小对促进污泥颗粒化进程的强化作用不明显,当磁性活性炭的粒径为140目和200目时,活性污泥很容易以其作为"成核"载体快速形成好氧颗粒污泥,并且形成的颗粒污泥结构紧密,沉降速率快.采用高斯函数分析污泥粒径分布和标准偏差发现,反应器运行的第50 d,3号和4号反应器内污泥平均粒径均达到了780μm以上,明显高于其他反应器,标准偏差分别为318.9μm和362.3μm,两反应器内形成的颗粒污泥粒径较均匀,处理系统较稳定.与此同时,投加不同粒径的磁性活性炭均有利于促进污泥胞外蛋白质PN含量的增加,对胞外多糖PS的含量影响不大;但合适的磁性活性炭粒径(140目和200目)越有利于污泥PN的分泌,颗粒化程度明显的3号和4号反应器的PN/PS比值均高于其他3个反应器.磁性炭基好氧颗粒污泥的形成符合"惰性内核模型".此外,3号、4号反应器对废水TN和TP的去除率分别达到50%和60%以上,均高于其他反应器.     

河流CO2与CH4排放研究进展

河流作为连接海-陆两大碳库的主要通道,其水-气界面二氧化碳(CO_2)与甲烷(CH_4)排放构成全球碳循环的重要环节,对全球气候变暖的贡献不容小觑.明确河流水体CO_2与CH_4产排过程、时空特征以及控制因素是认识河流生态学功能以及其对变化环境响应的重要内容.基于当前河流CO_2与CH_4排放研究进展,构建河流碳排放动力学概念框架(内源代谢、陆源输入),并从全球尺度、区域尺度、流域尺度综述了河流碳排放时空变异性特征以及存在的研究不足.在理解碳排放动力学概念框架和时空变异特征的基础上,构建了河流CO_2与CH_4动力学控制因子分层框架(内部因子:有机质、温度、营养盐;外部因子:水文、地貌、人类活动),深入探讨了河流碳排放的关键影响因素.最后,根据当前研究中存在的不足,提出河流碳排放应将纳入区域陆地碳平衡过程,今后研究重点应包括流域尺度上河流CO_2与CH_4内源产生与陆源输入相对贡献的量化研究、不同界面CO_2与CH_4产生与排放过程研究、高时空分辨率的监测数据的补充以及变化环境与人类活动干扰下河流碳排放的响应过程等,为理解河流生态学过程及生态系统功能提供基础,同时为我国进一步深入开展相关研究提供借鉴.     

南京北郊黑碳气溶胶的来源解析

利用七波段黑碳仪对2015年1~12月南京北郊地区黑碳(black carbon,BC)气溶胶实时监测,并结合黑碳仪模型对该期间内BC进行来源解析,探讨化石燃料排放产生BC(BCff)与生物质燃烧产生BC(BCbb)各自的贡献大小.结果表明,观测期间BC的吸收波长指数(α)和生物质燃烧对BC的贡献百分比(BB)的变化范围都较大但趋势较为一致;冬季α值偏高而夏季α值较低,表明不同季节时间BC来源和强度的差异性.BCff在各季节BC总浓度中占比略有不同但均高于75%;BC、BCff和BCbb的日变化趋势均呈双峰特征,在07:00~09:00和18:00~21:00左右浓度有最大值;全天中,BCff对BC贡献最大,浓度值约为BCbb的3~5倍;夜晚BC浓度普遍高于白天,其平均浓度值是白天的1.2倍.由浓度权重轨迹分析的结果可知,影响南京北郊地区高浓度BC的源区主要集中在浙江、安徽以及江西和福建等地区.     

Removal of perfluorinated surfactants from wastewater by adsorption and ion exchange——Influence of material properties,sorption mechanism and modeling

Perfluorooctane sulfonate(PFOS) has attracted increasing concern in recent years due to its world-wide distribution, persistence, bioaccumulation and potential toxicity. The influence of sorbent properties on the adsorptive elimination of PFOS from wastewater by activated carbons, polymer adsorbents and anion exchange resins was investigated with regard to their isotherms and kinetics. The batch and column tests were combined with physicochemical characterization methods, e.g., N_2 physisorption, mercury porosimetry, infrared spectroscopy, differential scanning calorimetry, titrations, as well as modeling. Sorption kinetics was successfully modelled applying the linear driving force(LDF) approach for surface diffusion after introducing a load dependency of the mass transfer coefficient βs.The big difference in the initial mass transfer coefficient βs,0, when non-functionalized adsorbents and ion-exchange resins are compared, suggests that the presence of functional groups impedes the intraparticle mass transport. The more functional groups a resin possesses and the longer the alkyl moieties are the bigger is the decrease in sorption rate.But the selectivity for PFOS sorption is increasing when the character of the functional groups becomes more hydrophobic. Accordingly, ion exchange and hydrophobic interaction were found to be involved in the sorption processes on resins, while PFOS is only physisorptively bound to activated carbons and polymer adsorbents. In agreement with the different adsorption mechanisms, resins possess higher total sorption capacities than adsorbents. Hence, the latter ones are rendered more effective in PFOS elimination at concentrations in the low μg/L range, due to a less pronounced convex curvature of the sorption isotherm in this concentration range.