Territorial vocal behavior in hybrid smooth froglets, Geocrinia laevis complex (Anura: Myobatrachidae)

Males of the parapatically distributed myobatrachid frogs Geocrinia laevis and G. victoriana have highly divergent advertisement calls. Furthermore, the two species differ strongly in the complexity of their vocal repertoires, with males of G. victoriana possessing, and those of G. laevis lacking, a distinct territorial vocalization (encounter call). We investigated the territorial vocal behavior of males in a persistent natural hybrid population. Most hybrid males possessed encounter calls functionally equivalent to those of G. victoriana, that were produced following exposure to playback of recorded advertisement calls presented at >110 dB peak sound pressure level. The territorial acoustic responses were not associated with an index of hybridity derived from the structure of the advertisement call, suggesting genetic and functional decoupling of the two components of the vocal repertoire; i.e., advertisement calls and encounter calls. This decoupling may be the result of sexual selection favouring those hybrids with pronounced territorial behavior and the associated vocalization, regardless of the structure of their advertisement calls.Communicated by A. Mathis     

Trace metals: Inputs, sedimentation and accumulation in San Vicente Bay, Chile

The present study deals with sediment dynamics affecting sediment-associated metal distributions in an embayment system experiencing pollution from coastal industries. Sedimentary metal content may originate from diagenetic processes of foundation rock on the bottom, allochthonous minerals from natural sources, and metals from industrial effluents along the coast. The study presents experimental estimations of quantities of metals entering the bay in industrial wastewater, measurements of metal content in particulate material captured in sediment traps, and metals distribution in surface sediments. Quantitative estimations of metals entering the system in industrial effluent showed the relation Pb Zn > Cu > Cr Ni > Cd. That of metals associated with particulate material from traps was Zn > Cr Cu > Pb > Ni > Cd and the abundance of metals in sediments was Zn > Cr > Cu > Pb > Ni > Cd. Finally, rates of bottom sediment accumulation are estimated in relation to the time of residence of water in the bay. The experimental data on sedimentation and sediment abundance were consistent with field observations on distribution and accumulation at sites of major sedimentation in this bay.     

Southern California's marine monitoring system ten years after the National Research Council evaluation

In 1990, the National Research Council (NRC) published two in-depth assessments of marine environmental monitoring effectiveness. The first of these, Managing Troubled Waters: The Role of Marine Environmental Monitoring, provided a national perspective and the second, Monitoring Southern California's Coastal Waters, examined the specifics of monitoring design and implementation in a densely populated, highly urbanized coastal region. The reports include explicit recommendations about the need for greater regionalization of monitoring efforts, supported by greater standardization of field, laboratory, and data analysis methods. They also identified the need for centralized data management and for greater flexibility in the language of standard discharge permits, flexibility that would permit discharge agencies to more readily participate in regional monitoring and research programs. Other recommendations identified a need for EPA and NOAA to focus on creating a national monitoring program structured as a network of coordinated local and regional efforts. Finally, the NRC emphasized the need for better reporting and for periodic review of monitoring's relevance to management concerns. In this paper, we use southern California as a test case to assess progress made in implementing the NRC's recommendations. We review progress made on each recommendation and discuss the features of the regulatory and management climate that contributed to or impeded this progress. We also consider whether, and to what extent, the NRC's recommendations remain relevant in the present context.     

滨岸带水华堆积与消散特征及其营养盐效应

为了解滨岸带植被、地形等地貌要素对蓝藻水华堆积及消散过程的影响,在太湖滨岸带设置不同形式的围格和植被实验区,通过逐日监测水体叶绿素a（Chl-a）的消长过程及同步营养盐变化,研究夏季蓝藻水华在湖泊滨岸带堆积与消散特征和营养盐效应.结果表明,滨岸带的地形地貌及植被状况对蓝藻水华的堆积程度及消散过程影响较大,软围隔营造的滨岸带静水环境,以及不同植被所形成的不同滞水区,显著加剧了蓝藻水华的局部堆积,从岸边挺水和浮叶植被区到开敞水域对照区,蓝藻水华的堆积程度依次递减;近岸挺水和浮叶植被区蓝藻水华堆积最严重,堆积时间最早,持续时间长;蓝藻水华堆积对营养盐等水质指标影响极大,堆积严重时该区域Chl-a含量达到了457.42μg/L,总氮（TN）达到11.04mg/L,总磷（TP）达到1.32mg/L;橡胶围格内浮叶植物区藻类堆积程度与近岸区类似,而浮叶植物与沉水植物混合区藻类堆积程度低于单一浮叶植物区;水体围隔能够加剧蓝藻水华的堆积,没有围隔的浮叶植物区藻类堆积程度最低.在蓝藻水华堆积过程中,蓝藻细胞仍在继续增殖,水体Chl-a仍会明显增加,而同期的水体营养盐的增幅小于Chl-a,甚至随着藻类生长消耗及生态系统的脱氮效应,溶解态氮磷下降明显.蓝藻水华消散过程中,TN、TP与Chl-a同步下降,但藻体中的氮磷释放到水中,导致堆积区的溶解态氮、磷有所增加,显示出明显的营养盐效应.本研究定量刻画了蓝藻水华局部堆积并快速致灾的地形地貌要素特点,揭示了蓝藻水华的水质与生态效应,为科学评估富营养化水体蓝藻水华的生态灾害风险提供科学依据.     

陆面模式Noah-MP模拟地表热通量的物理过程不确定性分析

陆面过程中的热量交换对于确定生态系统中的水文循环、边界层发展、天气和气候至关重要,然而目前陆面模式Noah-MP对地表热通量模拟的偏差在-180~180 W·m^-2之间,为明确模拟不确定性来源,本研究基于FLUXNET全球热通量观测数据,在5种气候类型、9类下垫面系统定量评估了Noah-MP感热和潜热通量模拟的不确定性.结果表明：Noah-MP在不同类型下对感热和潜热通量模拟的平均误差主要分布在-80~10 W·m^-2和-30~10 W·m^-2之间,模型在气候类型为热带和干旱气候以及下垫面类型为草地、针叶林、落叶阔叶林的模拟误差最大.研究发现植被过程是热通量模拟不确定性的主要来源,其次是水文过程和土壤过程;其中动态植被模型（DVEG）是植被过程模拟的主导因子,其次是湍流输送过程（SFC）、冠层气孔阻抗（CRS）和冠层辐射传输（RAD）.     

两种不锈钢在港口海水环境中的腐蚀行为和规律研究

目的研究304和316L不锈钢在我国不同港口海水全浸区浸泡不同周期后的腐蚀规律。方法进行港口海域实海全浸试验,利用三维视频拍摄、质量损失分析及图像处理等手段,对比分析不锈钢在青岛、舟山、三亚港口海水全浸区的腐蚀形貌、腐蚀速率、腐蚀深度和海生物附着面积。结果两种不锈钢表面以点蚀和缝隙腐蚀为主,304不锈钢表面还产生严重的隧道腐蚀。不同港口海水中,304和316L不锈钢的腐蚀速率均较低,316L不锈钢的耐蚀性优于304不锈钢。三港口海域不锈钢表面形貌的差异明显,三亚试样表面海生物附着最多,舟山试样表面附着大量泥沙,三亚港口海域不锈钢的腐蚀速率小于舟山港口海域。结论不同港口海水环境对不锈钢表面海生物种类及附着面积的影响显著,而不锈钢表面状态直接影响其腐蚀形貌。     

潮白河冲洪积扇典型包气带剖面反硝化强度垂向空间分布规律

以北京市潮白河冲洪积扇区域为研究区,选取两个典型剖面(S6和S8),通过测定不同采样深度(0～10 m)包气带反硝化强度值,分析了包气带反硝化强度的垂向空间分布特征,并识别了包气带反硝化强度垂向分布规律的影响因素.结果表明,典型剖面上各包气带土样的反硝化过程NO_3~--N浓度经历了上升、下降、上升这3个主要阶段; S6和S8剖面包气带反硝化强度取值分别为0. 002 6～0. 018 5 mg·(kg·d)~(-1)和0. 001 7～0. 023 3 mg·(kg·d)~(-1),总体反硝化强度水平较低;剖面垂向空间的反硝化强度总体呈现"S"型变化趋势; S6和S8剖面包气带反硝化强度的主控因素包括黏粒、硝酸盐、亚硝酸盐,并与以ACE和Shannon指数为代表的微生物多样性及反硝化菌亚硝酸盐还原酶基因nir K在一定深度范围内相关性显著.     

污染地下水零价铁原位反应带修复技术:理论·应用·展望

ZVI-IRZ(零价铁原位反应带)是一种新兴的地下水原位修复技术,具有工程造价低、施工简单、环境扰动小、修复效果好等优势, 而ZVI(零价铁)自身理化性质、场地的水文地球化学特征以及场地的污染状况等是影响修复效果的主要因素. 当前的研究内容主要包括IRZ(原位反应带)中ZVI的反应活性、稳定性、迁移性、生物毒性以及注入方式等方面. 在修复工程中存在的问题主要体现在:①ZVIs(细粒径零价铁)在含水介质中的迁移性较差,并且多采用Fe2+、pH等间接指标考察含水层中ZVIs的分布情况;②ZVIs表面钝化而诱发介质反应活性下降;③ZVIs的潜在生物环境效应尚不明确. 因此,需要加强对ZVIs表面改性手段、作用机制、老化特性、使用寿命、解钝化及钝化抑制技术等方面的理论与应用研究,还应关注ZVIs在环境中的归趋、转化机制和暴露路径,建立生态系统尺度上的评估体系; 同时,在实际应用中,需要在系统评估污染场地水文地质条件的基础上,加强对注入含水层中ZVIs及其反应产物的原位监测技术研发和监测体系完善.      

高等级公路采动变形破坏数值模拟研究

以南屯矿区及其上方的邹济公路为背景,采用FLAC~(3D)软件,对采动影响下的高等级公路破坏机理和破坏过程进行了研究。研究表明:高等级公路采动变形经历先"上凸"后"下凹"过程,且破坏程度随着公路级别的降低而增加。应尽量使公路位于采空区正上方,且延伸方向和工作面推进的方向一致;若公路位于采空区一侧时,路面向采空区一侧整体滑移和倾斜;若公路延伸方向与工作面推进方向垂直,应注意采空区公路两端的上凸变形;应避免公路与采空区斜交。在相同地质采矿条件下,随着深厚比的增加,路面破坏程度减小,且在一定范围内,路面最大下沉值与深厚比存在非线性关系。研究成果为邹济公路下开采方案和公路维修治理提供必要的理论和技术支持。     

黄土高原关键带土壤水分空间分异特征

地球关键带是人类生存和发展的关键区域。关键带发生的一系列物理、化学和生物过程与人类活动密切相关。土壤水分是黄土高原关键带的关键要素,同时又是黄土高原植被恢复与生态环境重建的决定因子。为揭示黄土高原关键带土壤水分的空间分异特征,采用网格(50m×50m)布点,雨季结束后采集0~500cm深度土壤样品,结合室内分析,结果表明:黄土高原小流域中73个样点0~500cm的土壤含水量分布范围介于1%~23%之间,降水对0~100cm土层的土壤水分补充明显;土壤水分在水平和垂直方向都表现出明显的空间异质性,在不同方向上的水分控制过程有所不同,是对土地利用方式、植被类型、地形要素、土壤质地等多因素综合响应的结果。充分理解关键带土壤水分空间的分异规律及其主控因素有助于该区小流域综合治理中的植被建造与布局,也有助于对该区土壤水文和生物地球化学过程的理解。