Concurrent exposure of bottlenose dolphins (Tursiops truncatus) to multiple algal toxins in Sarasota Bay, Florida, USA

Sentinel species such as bottlenose dolphins (Tursiops truncatus) can be impacted by large-scale mortality events due to exposure to marine algal toxins. In the Sarasota Bay region (Gulf of Mexico, Florida, USA), the bottlenose dolphin population is frequently exposed to harmful algal blooms (HABs) of Karenia brevis and the neurotoxic brevetoxins (PbTx; BTX) produced by this dinoflagellate. Live dolphins sampled during capture-release health assessments performed in this region tested positive for two HAB toxins; brevetoxin and domoic acid (DA). Over a ten-year study period (2000–2009) we have determined that bottlenose dolphins are exposed to brevetoxin and/or DA on a nearly annual basis (i.e., DA: 2004, 2005, 2006, 2008, 2009; brevetoxin: 2000, 2004, 2005, 2008, 2009) with 36% of all animals testing positive for brevetoxin (n = 118) and 53% positive for DA (n = 83) with several individuals (14%) testing positive for both neurotoxins in at least one tissue/fluid. To date there have been no previously published reports of DA in southwestern Florida marine mammals, however the May 2008 health assessment coincided with a Pseudo-nitzschia pseudodelicatissima bloom that was the likely source of DA observed in seawater and live dolphin samples. Concurrently, both DA and brevetoxin were observed in common prey fish. Although no Pseudo-nitzschia bloom was identified the following year, DA was identified in seawater, fish, sediment, snails, and dolphins. DA concentrations in feces were positively correlated with hematologic parameters including an increase in total white blood cell (p = 0.001) and eosinophil (p<0.001) counts. Our findings demonstrate that dolphins within Sarasota Bay are commonly exposed to two algal toxins, and provide the impetus to further explore the potential long-term impacts on bottlenose dolphin health.

Wave forecasts associated with hurricane landfalls in the vicinity of Cape Lookout, North Carolina

Hurricanes can cause extensive damage to the coastline and coastal communities due to wind-generated waves and storm surge. While extensive modeling efforts have been conducted regarding storm surge, there is far less information about the effects of waves on these communities and ecosystems as storms make landfall. This report describes a preliminary use of NCCOS’ WEMo (Wave Exposure Model; Fonseca and Malhotra 2010) to compute the wind wave exposure within an area of approximately 25 miles radius from Beaufort, North Carolina for estuarine waters encompassing Bogue Sound, Back Sound and Core Sound during three hurricane landfall scenarios. The wind wave heights and energy of a site was a computation based on wind speed, direction, fetch and local bathymetry. We used our local area (Beaufort, North Carolina) as a test bed for this product because it is frequently impacted by hurricanes and we had confidence in the bathymetry data. Our test bed conditions were based on two recent Hurricanes that strongly affected this area. First, we used hurricane Isabel which made landfall near Beaufort in September 2003. Two hurricane simulations were run first by passing hurricane Isabel along its actual path (east of Beaufort) and second by passing the same storm to the west of Beaufort to show the potential effect of the reversed wind field. We then simulated impacts by a hurricane (Ophelia) with a different landfall track, which occurred in September of 2005. The simulations produced a geographic description of wave heights revealing the changing wind and wave exposure of the region as a consequence of landfall location and storm intensity. This highly conservative simulation (water levels were that of low tide) revealed that many inhabited and developed shorelines would receive wind waves for prolonged periods of time at heights far above that found during even the top few percent of non-hurricane events. The simulations also provided a sense for how rapidly conditions could transition from moderate to highly threatening; wave heights were shown to far exceed normal conditions often long before the main body of the storm arrived and importantly, at many locations that could impede and endanger late-fleeing vessels seeking safe harbor. When joined with other factors, such as storm surge and event duration, we anticipate that the WEMo forecasting tool will have significant use by local emergency agencies and the public to anticipate the relative exposure of their property arising as a function of storm location and may also be used by resource managers to examine the effects of storms in a quantitative fashion on local living marine resources.

Larval development of the sidestriped shrimp (Pandalopsis dispar Rathbun) (Crustacea, Decapoda, Pandalidae) reared in the laboratory

Larval development of the sidestriped shrimp (Pandalopsis dispar) is described from larvae reared in the laboratory. The species has five zoeal stages and one postlarval stage. Complete larval morphological characteristics of the species are described and compared with those of related species of the genus. The number of setae on the margin of the telson in the first and second stages is variable: 11+12, 12+12, or 11+11. Of these, 11+12 pairs are most common. The present study confirms that what was termed the fifth stage in the original study done by Berkeley in 1930 was the sixth stage and that the fifth stage in the Berkeley’s study is comparable to the sixth stage that is described in the present study. The sixth stage has a segmented inner flagellum of the antennule and fully developed pleopods with setae. The ability to distinguish larval stages of P. dispar from larval stages of other plankton can be important for studies of the effect of climate change on marine communities in the Northeast Pacific and for marine resource management strategies.

松杉类植物花粉发育和传粉生物学的研究

本文用光学显微镜结合荧光技术对青扦花粉的发育过程进行了观察;用共聚焦显微镜观察了白扦生长花粉管细胞内的游离Ca2+分布;利用原子力显微镜对雪松和水杉花粉外壁的亚结构进行了研究：用透射电镜、扫描电镜及解剖镜等技术研究了侧柏、北美香柏、红豆杉、粗榧和白皮松的传粉机制，结果如下。 青扦花粉的发育过程与松科其它一些植物花粉的发育模式相似。从小孢子母细胞到成熟花粉约二十天左右。小孢子母细胞进入减数分裂前彼此分开，但在某些部位仍有连接。细胞质内有大量淀粉粒，在减数分裂过程中减少或消失，没有观察到明显的淀粉粒带。减数分裂中的胞质分裂为同时型，四分体为四面体型。小孢子刚从四分体释放出来时，气囊已开始形成，细胞中含大量淀粉粒。随着小孢子的发育，其体积增大，并出现液泡，细胞核移向一侧。小孢子第一次不对称分裂产生一个大的中央细胞和一个小的原叶细胞。中央细胞不久就进行第二次分裂产生精子器原始细胞和第二原叶细胞。原叶细胞形成后，其与中央细胞或精子器原始细胞之间的壁逐渐沉积胼胝质，以后随着原叶细胞的退化，胼胝质壁消失。精子器原始细胞分裂形成管细胞和生殖细胞，生殖细胞在散粉前分裂形成体细胞（精原细胞）和柄细胞（不育细胞）。成熟花粉为5细胞，但两个原叶细胞已退化消失。 白扦花粉在10%蔗糖+0.01%硼酸的液体培养基内培养12小时后开始萌发。在正常生长的花粉管中，其顶端有一个透明区，而透明区后则含有大量的贮藏物质颗粒。在停止生长的花粉管中透明区消失，而整个花粉管顶端也被储藏物质颗粒充满。正常生长的花粉管顶端有一个较高的Ca2+浓度。在停止生长的花粉管内不具有这样一个Ca2+梯度。 雪松和水杉二种花粉外壁中由孢粉素构成的亚结构单位形态相似，均呈颗粒状，但大小略有不同。雪松的长56-99 nm，宽42-74;水杉的长81-118 nm，宽43-98 nm。在雪松中这些亚单位紧密排列组成短棒状或球状的花粉外壁结构单位，再由几个到十几个这样的结构单位组成较大的岛屿状结构。在这些岛屿状结构之间有大小不一的空隙存在，整个花粉外壁由这样一些岛屿状结构交互连接形成。水杉花粉外壁的亚单位排列也较紧密，且有3-10个成群分布的趋势，但各群之间界限不明显。此外，雪松和水杉的花粉外壁亚单位均无螺旋状排列趋势，这一结果倾向于支持Southworth关于花粉外壁亚单位颗粒状并呈网状排列的观点。 白皮松胚珠倒生，其发育过程与松属的其它种相似，成熟胚珠珠孔端具两手臂状结构，有利于接收花粉。花粉具气囊。传粉期间，没有观察到传粉滴产生，但珠心顶端细胞解体形成花粉室。花粉室内可接受一至几个花粉，花粉在花粉室内的位置无明方向性。传粉时，胚珠处于大孢子线细胞时期。花粉在花粉室内萌发形成花粉管进入珠心组织，花粉管在珠心内生长一段时间后停止生长，并于次年春天重新启动生长。离体生长的花粉管顶端常有胼胝质产生，但顶端区域后的花粉管壁上却无胼胝质沉积。 侧柏、北美香柏、红豆杉和粗榧均为直生胚珠。传粉时胚珠产生传粉滴。在红豆杉胚珠发育早期，珠心表面细胞轮廓清晰;而在后期，其珠心表面则形成了一层膜状结构。这层膜状结构在传粉前随珠心细胞的解体而破裂，珠心细胞的降解产物参与了传粉滴形成。在传粉前和传粉期，珠心细胞内含大量的线粒体、内质网、高尔基体和小泡。传粉滴主要由珠心细胞分泌形成。这四种植物的花粉均无气囊，属可湿性花粉。红豆杉和粗榧的花粉水合时，内壁膨胀，外壁开裂。通常情况下，红豆杉花粉的外壁保留在传粉滴的表面，而花粉的其它部分沉入传粉滴内。侧柏和北美香柏的传粉滴授粉后，花粉进入传粉滴导致传粉滴的明显收缩。在侧柏中传粉滴授粉后100分钟内就完全收缩进入珠孔。传粉滴收缩的速率与所授花粉数量和花粉的种类有关。与侧柏亲缘关系较近植物花粉引起传粉滴的收缩速率和侧柏自身花粉引起的传粉滴收缩速率相似;反之，收缩速率变慢。侧柏传粉滴的收缩可能主要是由于花粉减弱胚珠分泌的结果。但授粉不引起红豆杉和粗榧传粉滴的明显收缩。在红豆杉和粗榧中，从授粉到传粉完全收缩需要20-24小时。这两种植物传粉滴的收缩可能主要是蒸发引起的非代谢性过程，与侧柏和美香柏属于不同的传粉滴收缩机制。

Bycatch in the tuna purse-seine fisheries of the western Indian Ocean

Bycatch taken by the tuna purse-seine fishery from the Indian Ocean pelagic ecosystem was estimated from data collected by scientific observers aboard Soviet purse seiners in the western Indian Ocean (WIO) during 1986–92. A total of 494 sets on free-swimming schools, whale-shark-associated schools, whale-associated schools, and log-associated schools were analyzed. More than 40 fish species and other marine animals were recorded. Among them only two species, yellow-fin and skipjack tunas, were target species. Average levels of bycatch were 0.518 metric tons (t) per set, and 27.1 t per 1000 t of target species. The total annual purse-seine catch of yellowfin and skipjack tunas by principal fishing nations in the WIO during 1985–94 was 118,000–277,000 t. Nonrecorded annual bycatch for this period was estimated at 944–2270 t of pelagic oceanic sharks, 720–1877 t of rainbow runners, 705–1836 t of dolphinfishes, 507–1322 t of triggerfishes, 113–294 t of wahoo, 104–251 t of billfishes, 53–112 t of mobulas and mantas, 35–89 t of mackerel scad, 9–24 t of barracudas, and 67–174 t of other fishes. In addition, turtle bycatch and whale mortalities may have occurred. Because the bycatches were not recorded by some purse-seine vessels, it was not possible to assess the full impact of the fisheries on the pelagic ecosystem of the Indian Ocean. The first step to solving this problem is for the Indian Ocean Tuna Commission to establish a pro-gram in which scientific observers are placed on board tuna purse-seine and longline vessels fishing in the WIO.

Interactions between climatic variables controlling subalpine tree growth: implications for climatic history of the Sierra Nevada, California

EXTRACT (SEE PDF FOR FULL ABSTRACT): Tree-ring records from foxtail pine (Pinus balfouriana) and western juniper (Juniperus occidentalis) growing near tree line in the eastern Sierra Nevada, California, show strong correlations with summer temperature and winter precipitation. Response surfaces portraying tree growth as a function of summer temperature and winter precipitation indicate a strong interaction between these variables in controlling growth. ... Above average growth for both foxtail pine and western juniper from AD 1480 to 1570 can be interpreted as indicating an extended period of warm, moist conditions unequalled during the 20th century.

东灵山森林生态系统若干水分问题的研究

东灵山地区年均降水量659.7mm，单次降水以雨量小、雨强低的降水为主。水汽压（年均17.7mb）、相对湿度（年均66％）的季节变化呈现生长季高、冬季低的趋势。年均蒸发量1019.5mm;气温、风速、日照时间和水压与月蒸发量和日蒸量相关显著;气温、日照时间和水压分别在11-6月、7－8月和9－10月为决定蒸发量的首要因子。枯枝落叶层、土壤层湿度主要受前十日降水量和坡向影响。 植物体含水量生长季节较高，冬季较低;含水量随径级的增大而降低。六个灌木树种的平均含水量大小顺序为：毛榛（48.62%）最高荆条（36.32%）最低;七个乔木树种水分含量为油松，56.14%;蒙椴，54.19%;华北落叶松，52.91%;五角枫，43.64%;辽东栎，41.87%;棘皮桦，41.13%;大叶白腊，37.79%。几种植被类型的储水量为：辽东栎林，82.08mm;华北落叶松林，47.35mm;混交林，34.60mm;油松林，31.33mm;灌丛，12.40mm。各树种叶片日最低水势的季节均值为：辽东栎，-16.1bar;五角枫，-15.8bar;大叶白腊，-15.1bar;糠椴，-13.4bar;棘皮桦，-12.3bar;蒙椴，-12.2bar。叶片水势的日间变化均呈一“V”形曲线;光照在叶片水势的日间变化中起着决定性作用。 96年各树种平均单株树干茎流量为辽东栎，30.3mm(4.19%);华北落叶松，16.1mm(2.22%);油松，8.9mm(1.23%);棘皮桦，2.9mm(0.40%)。两个生长季各林分冠层的水量平衡为：辽东栎林，树干流茎量101.87mm(9.18%)，穿透降水量823.08mm(74.15%)，截留量185.05mm(16.67%);华北落叶松林，树干径流量66.88mm(6.03%)，穿透降水量836.92mm(75.40%)，截留量206.20mm(18.58);混交林，树干径流量50.13(4.52%)，穿透降水量846.78mm(76.29%)，截留量212.20mm(19.12%);油松林，树干径流量33.90mm(3.05%)，穿透降水量934.88mm(84.22%)，截留量141.22mm(12.72%)。多元回归分析表明，树干流茎量S与降水量P和前24小时降水量P_1呈显著正相关关系;穿透降水量T与降水量P和最大雨强M正相关显著。附加截留量与降水时间成正比。 枯枝落叶层的生物量为：油松林，25.56t/hm~2;华北落叶松林20.01t/hm~2;辽东栎林，8.31t/hm~2;混交林，7.98t/hm~2。枯枝落叶层的平均实际持水量和有效持水量均以油松林最大，其次是华北落叶松林，而混交林和辽东栎林较低;枯枝落叶层的实际持水量和有效持水量的季节变化分别与前十日降水量P10成正相关和负相关关系。枯枝落叶层的截留量为油松林＞华北落叶松林＞辽东栎林＞混交林;油松林（145.632mm和90.800mm）混交林(61.816mm和54.504mm)。油松林、辽东栎林、混交林和华北落叶松林去除枯枝落叶层后，土壤入渗量比对照平均降低100mm以上;表层土壤含水量分别比对照土壤下降了6.26、18.26、15.06和15.07个百分点。地表径流量分别增加了，辽东栎林34.299mm(603%)和15.816mm(525%);油松林14.593mm(732%)和10.584mm(1321%);混交林12.004mm(181%)和7.275mm(364%);华北落叶松林3.555mm(118%)，3.275mm(229%)。96年生长季，各土壤流失量分别增加了：油松林172.751t/hm~2(124倍);辽东栎林836.500t/hm~2(119倍);混交林172.499t/hm~2(47倍);华北落叶松林11.557t/hm~2(11倍)。表层土壤容重分别增加了：油松林15.0%和20.6%，辽东栎林18.4%和28.2%，混交林11.5%和38.5%，华北落叶松林4.3%和17.1%。 0-60cm深度土壤容重平均值的大小顺序为：草地>灌丛>辽东栎林>油松林>混交林>华北落叶松林;而土壤孔隙度的大小顺序为华北落叶松林>混交林>油松林>辽东栎林>灌丛>草地。两个生长季为土壤实际储水量的均值：油松林，124.45mm，78.62mm;辽东栎林，131.23mm，87.72mm;混交林，180.41mm，113.90mm;华北落叶松林，165.53mm，127.95mm;灌丛，172.50mm，89.81mm;草地，152.92mm，89.59 mm分别比干旱年份97年高出45.83mm、43.51mm、51.63mm、37.58mm、82.69mm和63.33mm。两个生长季的地表径流量为草地，30.930mm(2.79%);灌丛，16.321mm(147%);油松林，2.911mm(0.26%);辽东栎林，8.703mm(0.78%);混交林，8.625mm(0.78%);华北落叶松林，4.447mm(0.40%)。油松林、混交林和华北落叶松林地表径流量与降水量P(mm)和最大雨强(mm/h)正相关显著;而辽东栎林、灌丛和草地的地表径流量则与降水量P(mm)、平均雨强Q(mm/hr)和最大雨强M(mm/hr)三者之间呈显著正相关关系。与草地相比(1220.093kg/hm~2，100％)，灌丛、辽东栎林、混交林、油松林和华北落叶松林96年生长季的土壤流失量分别降低了85.05%、94.26%、96.99%、98.86和99.14%。 降水量是影响小流域径流量时间变化的主要因素;南沟和马牙石沟96年的径流量分别是97年的8.19倍和7.87倍，而径流深(46.25mm，52.75mm)分别比97年(5.65mm,6.70mm)高出40.60mm和46.05mm。两个小流域由于面积的差异而使南沟两年的径流量分别比马牙石沟高出2773.136m~3(13.15%)和235.434m~3(8.79%)。96年和97年马牙石沟径流深比南沟高出6.5mm(14.05%)和1.05mm(18.58%)。在地处大陆性季风气候区的东灵山地区，用0.010m~3/min/km~2/hr能较好地分割小流域的洪峰和基流。在五次暴雨水文曲线中，马牙石沟的快速径流量分别比南沟高出25.00%到143.33%。五次洪水水文响应R的平均值南沟为0.218%，马牙石沟为0.404%;与海洋性气候地区相比，东灵山地区小流域的R值要低一到两个数量级。马牙石沟洪峰流量Qp的平均值为418.772L/min要比南沟(281.191L/min)大48.9%。东灵山地区小流域的洪水径流过程可分为三种类型。

Radiolarian flux in the Santa Barbara Basin as an index of climate variability

Annual radiolarian flux (1954-1986) extrapolated from varved Santa Barbara Basin sediments was compared to instrumental data to examine the effect of interannual climate variability. Paleo-reconstructions over large geographic areas or 10^3 years and longer typically rely on changes in species composition to signal environment or climate shifts. In the relatively short period studied, climate fluctuations were insufficient to significantly alter the assemblage, but there was considerable variability in the total flux of radiolarians. This variability, greatest on 5- to 25-year time scales, appears to be linked to regional climate variability. Total flux correlates to regional California sea surface temperature and the composite of sea level pressure over the Northern Hemisphere for years of high radiolarian flux resembles positive PNA circulation.