Interceptions of Nonindigenous Plant Pests at US Ports of Entry and Border Crossings Over a 17-year Period

Despite the substantial impacts of nonindigenous plant pests and weeds, relatively little is known about the pathways by which these organisms arrive in the U.S. One source of such information is the Port Information Network (PIN) database, maintained by the U.S. Department of Agriculture, Animal and Plant Health Inspection Service (APHIS) since 1984. The PIN database is comprised of records of pests intercepted by APHIS personnel during inspections of travelers’ baggage, cargo, conveyances and related items arriving at U.S. ports of entry and border crossings. Each record typically includes the taxonomic identify of the pest, its country of origin, and information related to the commodity and interception site. We summarized more than 725,000 pest interceptions recorded in PIN from 1984 to 2000 to examine origins, interception sites and modes of transport for nonindigenous insects, mites, mollusks, nematodes, plant pathogens and weeds. Roughly 62% of intercepted pests were associated with baggage, 30% were associated with cargo and 7% were associated with plant propagative material. Pest interceptions occurred most commonly at airports (73%), U.S.-Mexico land border crossings (13%) and marine ports (9%). Insects dominated the database, comprising 73 to 84% of the records annually, with the orders Homoptera, Lepidoptera and Diptera collectively accounting for over 75% of the insect records. Plant pathogens, weeds and mollusks accounted for 13, 7 and 1.5% of all pest records, respectively, while mites and nematodes comprised less than 1% of the records. Pests were intercepted from at least 259 different locations. Common origins included Mexico, Central and South American countries, the Caribbean and Asia. Within specific commodity pathways, richness of the pest taxa generally increased linearly with the number of interceptions. Application of PIN data for statistically robust predictions is limited by nonrandom sampling protocols, but the data provide a valuable historical record of the array of nonindigenous organisms transported to the U.S. through international trade and travel.     

惠州西湖磷模型的初级研究

国家4A旅游景区之一的惠州西湖地处亚热带地区,属于典型的浅水型城市湖泊.在西湖水体完全混合的假设和西湖实地调查和2003年～2005年监测数据的基础上,对惠州西湖建立了零维总磷模型.文中对总磷模型进行了参数的率定、校正,并用模型对2003年10月到2004年9月一周年进行总磷浓度的模拟预测,从而验证了该模型在惠州西湖水质预测中的适用性和可行性.根据西湖底泥磷释放率的特征提出修正模型,大大降低了原模型模拟误差,更精确拟合惠州西湖的总磷浓度的动态变化,有助于西湖的长期预测工作的进一步开展.     

惠州市景观格局空间分异特征的梯度分析

本文将景观指数、梯度分析和移动窗口法相结合,分析了惠州市景观格局的空间分异特征。以中心城区为起点,向外等距设置辐射状梯度带;同时结合研究区的特点,设置了4个不同方向的样带。综合运用景观指数粒度效应分析和土地面积变化评价指数模型,确定适合研究区的分析粒度;考虑到景观格局的各向异性,计算不同方向的半变异函数和相应的块基比,确定不同方向样带的分析幅度;采用移动窗口法分析不同方向样带的景观格局特征。结果表明:(1)50 m的栅格大小为适合研究区景观格局分析的粒度值,4条样带上移动窗口的适宜分析尺度分别为750、850、1350、1150 m;(2)从中心城区到外围区域,可将惠州市依次划分为城市中心区、农业区、城市副中心区、过渡区和生态保育区;(3)高强度城市化地区和远郊区的景观组分类型单一,优势度特征明显,城市边缘区或城乡过渡带的景观异质性增加,破碎化程度高;(4)不同方向的样带能够反映景观格局的方向分异特征,是城市景观梯度分析的有效手段。     

Enhancing Port State Control in Polar Waters

Abstract

In recent years, the role of Port State Control (PSC) with respect to polar navigation has become increasingly important. However, international rules for PSC of fishing vessels plying polar waters are incomplete and uniform inspection guidelines have not yet been adopted, nor has a coordinated mechanism been created. This article argues that fishing vessels should be incorporated into the Polar Code and that at the practical level, states should promote the application of the Port State Control Officer Guidelines adopted under the Paris Memorandum of Understanding and encourage cooperation among the different PSC organizations that cover polar waters.     

Edge effects in patchy seagrass landscapes: The role of predation in determining fish distribution

Predation is often described as an underlying mechanism to explain edge effects. We assessed the importance of predation in determining edge effects in seagrass using two approaches: a video survey to sample predators at small scales across seagrass edges, and a tethering experiment to determine if predation was an underlying mechanism causing edge effects. Underwater videos were placed at four positions: middle of seagrass patches; edge of seagrass; sand immediately adjacent to seagrass and sand distant from seagrass. Fish abundances and the time fish spent in view were measured. The main predatory fish (Australian salmon, Arripis spp.) spent more time over adjacent sand than other positions, while potential prey species (King George whiting, Sillaginodes punctata (Cuvier), recruits) were more common in the middle of seagrass patches. Other species, including the smooth toadfish, Tetractenos glaber (Freminville), and King George whiting adults, spent more time over sand adjacent to seagrass than distant sand, which may be related to feeding opportunities. King George whiting recruits and pipefish (Stigmatopora spp.) were tethered at each of the four positions. More whiting recruits were preyed upon at outer than inner seagrass patches, and survival time was greater in the middle of shallow seagrass patches than other positions. Relatively few pipefish were preyed upon, but of those that were, survival time was lower over sand adjacent to seagrass than at the seagrass edge or middle. Video footage revealed that salmon were the dominant predators of both tethered King George whiting recruits and pipefish. The distribution of predators and associated rate of predation can explain edge effects for some species (King George whiting) but other mechanisms, or combinations of mechanisms, are determining edge effects for other species (pipefish).     

洋山港潮间带大型底栖动物群落结构及多样性

2009-2010年在洋山港海域大洋山岛和圣姑礁进行四个季度潮间带大型底栖动物生态学研究。共采集到大型底栖动物61种,以广布种为主,部分为河口低盐种,其中软体动物22种,环节动物16种,节肢动物12种,苔藓动物5种,腔肠动物4种,星虫动物和棘皮动物各1种。优势种为短滨螺(Littorina brevicula)、多齿围沙蚕(Perinereis nuntia)、日本笠藤壶(Tetraclita japonica)、齿纹蜒螺(Nerita yoldii)和特异大权蟹(Macromedaeus distinguendus)。丰度和生物量在不同季节明显不同(P<0.05):丰度的最高值出现在春季,为(3204.9±837.84)个/m²,最低值出现在秋季,仅为(2213.2±731.27)个/m²;生物量的最高值则出现在夏季(2233.2±1493.42)g/m²,冬季最少,仅为(819.95±484.80) g/m²。大洋山岛和圣姑礁的丰度和生物量具有较大差异(P<0.05):年均丰度以大洋山断面较高,为(3090±742.74)个/m²,圣姑礁断面较低,为(2133±372.51)个/m²;而年均生物量则以圣姑礁断面较高,为(1711.1±1180.76) g/m²,大洋山断面较低,仅为(1028.5±627.61) g/m²。运用ABC曲线、等级聚类和MDS对大型底栖动物群落结构分析发现:大洋山潮带间大型底栖动物群落尚未受到干扰或干扰较轻,群落结构相对稳定;而圣姑礁断面的潮间带大型底栖动物群落受到了中度的干扰,群落结构稳定性下降。与15年前的研究相比,圣姑礁大型底栖动物的密度和生物量均有大幅度的降低,这与洋山港海域盐度的升高、生态环境变化和人为干扰强度增加等有关。     

氮、磷对热带浅水湖泊惠州西湖蓝藻的控制

湖泊富营养化常导致蓝藻生物量的增加,水质恶化.于2011年2月至12月对热带浅水湖泊惠州西湖六个湖区的蓝藻群落结构进行研究,以了解其时空变化特征及主要影响因素.结果表明,以沉水植物为优势的元妙观湖区与南南湖蓝藻无明显的优势种;平湖蓝藻优势种为银灰平裂藻(Merismopedia glauca)和湖丝藻(Limnothrix sp.),南丰湖、北丰湖和北南湖的主要优势种均为银灰平裂藻(Merismopedia glauca).平湖、南丰湖、北丰湖和北南湖蓝藻丰度及生物量存在显著的季节变化.相关分析显示惠州西湖夏季蓝藻生物量受氮、磷盐控制.冬季温度的影响,蓝藻生物量与氮、磷的相关性不显著.     

First Australian records of Scalaronoba Powell, 1927 (Gastropoda: Aclididae?), with the description of two new species from Victoria

The marine microgastropod genus Scalaronoba Powell, 1927 (Gastropoda: Aclididae?) is recorded from Australia for the first time, with the new species Scalaronoba kryptopleurakia n. sp. and Scalaronoba arenula n. sp. described from central Victoria. Three other indeterminate Victorian specimens are illustrated and discussed. These are the first records for the genus outside New Zealand. The uncertainty of the familial placement of Scalaronoba is discussed. These species are noted as being amongst the smallest gastropods to be recorded from Victorian waters. http://www.zoobank.org/urn:lsid:zoobank.org:pub:98860E57-6EC0-4F15-93D7-34A823E41E07     

Quantitative Ecological Risk Assessment of Industrial Accidents: The Case of Oil Ship Transportation in the Coastal Tropical Area of Northeastern Brazil

Accidents such as toxic spills can cause massive damage to local ecosystems and hamper the sustainable development of hazardous industries. Models that only consider regularly occurring pollution are unable to truly quantify ecological risks (ecorisks) from these industries. This work presents a methodology capable of quantifying ecorisks related to rare and extreme events such as industrial accidents. We developed a procedure that integrates information from different studies that contributes to characterize ecorisks from industrial accidents: (1) reliability analysis, (2) fate and transport modeling, (3) individual-level toxicological assessment, and (4) population modeling. The methodology is exemplified by an application to oil ship transportation to supply Brazil's Suape industrial complex. A fish population was strategically chosen to represent the ecosystem's health of Suape beach. For the critical accidental scenarios, their frequencies of occurrence were estimated and the space–time evolution of oil simulated. The ecorisks were quantified in terms of time and population probability of fish extinction, categorized and compared against a no-accident scenario. The total ecorisks from all scenarios were presented as a FN curve, where N is the average number of deaths in the population and F the cumulative frequency of accidents with potential to cause N or more deaths.     

Some ecological observations on two agarophytes from India

The responses of Gracilaria corticata and Gelidiopsis gracilis (agarophytes) to different concentrations of sea water, pH range and lights of different colours have been studied to understand the ecological amplitudes. Both algae had a very narrow range of salinity tolerance from 29.0 to 33.1. With respect to pH also, they could thrive only under pH values from 7.0 to 8.0. Growth of these algae was retarded under all coloured lights. However, under yellow light growth was nearer to that of controls.