Impact of marine heatwaves for sea turtle nest temperatures

There are major concerns about the ecological impact of extreme weather events. In the oceans, marine heatwaves (MHWs) are an increasing threat causing, for example, recent devastation to coral reefs around the world. We show that these impacts extend to adjacent terrestrial systems and could negatively affect the breeding of endangered species. We demonstrate that during an MHW that resulted in major coral bleaching and mortality in a large, remote marine protected area, anomalously warm temperatures also occurred on sea turtle nesting beaches. Granger causality testing showed that variations in sea surface temperature strongly influenced sand temperatures on beaches. We estimate that the warm conditions on both coral reefs and sandy beaches during the MHW were unprecedented in the last 70 years. Model predictions suggest that the most extreme female-biased hatchling sex ratio and the lowest hatchling survival in nests in the last 70 years both occurred during the heatwave. Our work shows that predicted increases in the frequency and intensity of MHWs will likely have growing impacts on sea turtle nesting beaches as well as other terrestrial coastal environments.     

福建南日群岛秋季海洋生态环境诊断与评价

根据2007年9月和10月福建南日岛生态调查资料,从海水水质、海水营养结构与营养水平、生物多样性等3个方面诊断与评价了南日群岛海域环境现状,利用综合质量指数法对海洋生态环境质量进行综合评价,并探讨了不同评价指数的关系及合理性.结果表明:海域的pH、溶解氧(DO)、化学需氧量(COD)、Pb、Cd、Hg、As含量均符合第二类海水水质标准.71%站位的磷酸盐、14%站位的无机氮和7%站位的石油类污染物超第二类海水水质标准.海水水质总体属于较好等级,营养结构表现为氮限制,大部分海域处于富营养化状态,依据浮游生物的多样性指数评价结果为轻污染-清洁水平.生态环境综合质量指数评价结果表明南日群岛海域生态环境总体处于良好水平.利用不同的评价指数对海域环境健康状况进行诊断的结果存在一定差异.在实际评价中应综合运用化学指标和生物指标,才能得到相对客观的结论.     

A mesoscale analysis of floristic patterns in the south-west Finnish Archipelago

Aim To identify the ecological gradients based on the flora on a mesoscale in an archipelago. To interpret the results of the ordination and the classification of a grid cell‐based botanical data set, with several environmental and geographical attributes. To compare the mesoscale distribution patterns of vascular plants with patterns previously observed on an island scale, and to develop a floristic zonation of the study area. Location The south‐west Finnish Archipelago. Methods Vascular plant species‐lists from over 1500 localities were assigned to 5 × 5 km grid cells. The grid cell‐based floristic data were subjected to both unconstrained [detrended correspondence analysis (DCA)] and constrained [detrended canonical correspondence analysis (DCCA)] gradient analyses. The results of DCA were interpreted with calculated weighted averages of Ellenberg's indicator values for vascular plants, the number of occurring taxa and indices for the strength of human influence and the occurrence of limestone. The results of DCCA were interpreted with geographical attributes of the grid cells and the occurrence of limestone. The grid cells were clustered using two‐way indicator species analysis (twinspan ). Results Both the unconstrained and the constrained ordinations gave consistent and interpretable results. The main ecological gradient runs from the grid cells containing species‐rich islands with high human impact to grid cells containing species‐poor islands with low human impact. This gradient also represents the continuum from areas with large islands near the mainland, to the outermost areas at the edge of the open sea. The secondary gradient was shown to be a gradient of soil reaction. twinspan gave a clustering primarily based on the location of the grid cells on an inner–outer archipelago gradient, but the occurrence of limestone also influenced the classification. The archipelago was divided into five non‐homogeneous areas based on the twinspan clusters. The detected gradients correspond well with the gradients detected in a similar island‐level analysis. Main conclusions The two major ecological gradients in the study area seem to be robust, which is indicated by the similar results obtained both on an island and on a mesoscale. A shift from local and regional processes to broader geographical gradients probably starts to occur at the applied scale. The distribution patterns are strongly affected by the inner–outer archipelago gradient and the occurrence of limestone.     

Prasiolales (Trebouxiophyceae,Chlorophyta) of the Svalbard Archipelago: diversity,biogeography and description of the new genera Prasionella and Prasionema

Species of Prasiolales (Trebouxiophyceae, Chlorophyta) are among the most common terrestrial and freshwater algae in polar regions. Comprehensive molecular studies of this group are available for Antarctica, but not yet for Arctic regions. We examined the diversity of the Prasiolales in the Svalbard Archipelago combining morphological observations of field-collected material, culture studies, molecular data (plastid rbcL and tufA sequences) and literature records. We confirmed the widespread occurrence of Prasiola crispa and P. fluviatilis, species recorded from Spitsbergen since the 19th century. Molecular phylogenetic analyses led to the discovery of two new genera of Prasiolales. Prasionema payeri is morphologically identical to filamentous stages of P. crispa, but represents an early-diverging lineage in the order. Prasionella wendyae is a colonial alga reproducing by aplanospores; its phylogenetic position is among the basal lineages of the order, but it could not be reliably reconstructed due to weak statistical support. The inclusion of P. wendyae in the prasiolalean phylogeny determined the paraphyly of Rosenvingiella, requiring the establishment of the new genus Rosenvingiellopsis for R. constricta. A poorly known species described from Spitsbergen, Ulothrix discifera, is transferred here to Rosenvingiella. Whereas some species of Prasiolales have bipolar distribution (P. crispa), others appear to be restricted to one or other of the poles. Our results suggest that polar regions are still a major repository of unknown algal diversity and highlight the importance of continued field surveys and the use of molecular data.     

甲藻孢囊在长山群岛海域表层沉积物中的分布

2007年10月,在大连长山群岛海域采集了25个站点的表层沉积物,研究了甲藻孢囊的水平分布。在沉积物样品中共检测出甲藻孢囊46种,其中Pentaphasodinium dalei和Warowia rosea,在我国是首次报道。各站位孢囊种类数在7-20之间,平均14种;丰度在182-2960 个/g干重之间,平均为1201 个/g干重。香农-威纳指数(H')的变化范围为2.4-3.4。麻痹性贝毒藻--亚历山大藻的孢囊在调查海域分布广泛,最高密度达829个/g干重,可能是造成该海域虾夷扇贝贝毒超标的原因之一。     

A study on the community analysis using three-factorial data (time x site x species)

1. This study is to demonstrate that the analysis of biological communities using scaling unstandardized squared Euclidean distance is extremely effective to deal with data which are quite generally collected by 3 factors (time x site x species).
2. The main part of this study has been explained in detail byWilliams andStephenson (1973). We have conducted some discussion introducing mathematic complementary explanation as well as expansive interpretation.
3. The dissimilarity measure based on squared Euclidean distance is used to classify clusters from a dendrogram obtained by cluster analysis. The outline of the community structure can be known by comparing the values of mean variance per comparison and interaction.
4. The table of mutual comparison among clusters introduces dynamic pattern expression for community. Contributions by species to time and site are capable of expressing a concrete role of the species.
5. We apply the technique above to the demersal fish community in Shijiki Bay, Hirado Island, Nagasaki Pref. Number of individuals caught with Gochi trawls at 11 fixed stations in 1975–1984 are used as material for analysis. 84 species is accounted.

     

Wallace's Line and plant distributions: two or three phytogeographical areas and where to group Java?

Wallace's Line or its variants divide the Malay Archipelago or Malesia into a western and eastern area, but is this suitable for plant distributions? Indeed, all boundaries satisfactorily divide Malesia into two parts, stopping far more species east or west of a line than disperse over the boundary. However, phenetic analyses (principal components analysis, nonmetric multidimensional scaling analysis and the unweighted pair group method with arithmetic mean) of 7340 species distributions revealed a stronger partitioning of Malesia into three instead of two regions: the western Sunda Shelf minus Java (Malay Peninsula, Sumatra, Borneo), central Wallacea (Philippines, Sulawesi, Lesser Sunda Islands, Moluccas, with Java), and the eastern Sahul Shelf (New Guinea). Java always appears to be part of Wallacea, probably because of its mainly dry monsoon climate. The three phytogeographic areas equal the present climatic division of Malesia. An everwet climate exists on the Sunda and Sahul Shelves, whereas most of Wallacea has a yearly dry monsoon. During glacial maxima, the Sunda and Sahul Shelves became land areas connected with Asia and Australia, respectively, whereas sea barriers remained within Wallacea. Consequently, the flora of the two shelves is more homogeneous than the Wallacean flora. Wallacea is a distinct area because it comprises many endemic, drought tolerant floristic elements. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 531–545.     

The importance of historical ecology for interpreting evolutionary processes in plants of oceanic islands

Oceanic islands and archipelagos are natural laboratories for investigating patterns and processes of evolution. Islands change with the course of time, resulting in a dynamic ontogeny over millions of years. The combined forces of tectonic plate subsidence and erosion from waves, wind, and rainwater bring about substantial geomorphological change over millions of years, until islands eventually disappear under the sea. Added to these long‐term natural changes to the environment of the islands are the changes caused by human activities in recent centuries. After humans reach a previously unpopulated island, they utilize the natural resources for their own survival, cutting forests for making houses, boats, and firewood. The size of the human population and the length of time on the island determine the degree of environmental impact. Evolutionary processes in plants of oceanic islands take place during ontogeny of the islands, resulting in population divergence, speciation, and hybridization. Due to the dramatic alterations suffered by many islands over millions of years, the present patterns of distribution and ecology of species within endemic groups may have little to do with the patterns when the species originated. Understanding these environmental changes is fundamental to infer a founder effect, reasons for levels of genetic variation within and among populations, and modes of speciation. Special caution must be exercised while making comparisons between groups located on islands of different geological ages and that have endured differing environmental modifications from humans. Examples are provided from the Juan Fernández Archipelago and Lord Howe Island.     

浙江韭山列岛的黑嘴端凤头燕鸥繁殖群调查初报

2004年7月28日～8月2日,在考察浙江象山韭山列岛省级海洋生态自然保护区时,发现了正处于繁殖中期的黑嘴端凤头燕鸥(Sterna bernsteini)的群体混群于大凤头燕鸥(S．bergii)的繁殖群中。据估测,大凤头燕鸥的种群数量为3500～4500只,黑嘴端凤头燕鸥的种群数量为10～20只。这是目前继2000年马祖群岛发现黑嘴端凤头燕鸥繁殖群之后的第2个繁殖群体。