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An optimal management strategy for stochastic population dynamics of released Plecoglossus altivelis in rivers

International Journal of Modeling, Simulation, and Scientific Computing 2017年第2期8卷 204-219页

作者： Yuta Yaegashi Hidekazu Yoshioka Koichi Unami Masayuki Fujihara Graduate School of Agriculture Kyoto University Kitashirakawa Oiwake-choSakyo-kuKyoto City Kyoto Prefecture606-8502Japan Faculty of Life and Environmental Science Shimane university Nishikawatsu-cho 1060 Matsue CityShimane Prefecture690-8504Japan Graduate School of Agriculture Kyoto UniversityKitashirakawa Oiwake-cho Sakyo-kuKyoto CityKyoto Prefecture606-8502Japan

Excessive predation pressure from the waterfowl Phalacrocorax carbo(Great Cormorant)on Plecoglossus altivelis(Ayu)has recently been a severe problem of river environment in *** fishery cooperatives are currently suffering from economic difficulties due to decrease of the fish catch of *** fishery cooperatives and municipalities have been enthusiastically trying to develop countermeasures that can effectively reduce the predation pressure;however,their effectiveness and efficiency have not been systematically quantified *** aim can be achieved with the help of an appropriate mathematical *** this paper,based on a pure death process,a practical stochastic control model for population dynamics of released *** in river environment under predation pressure from ***,harvesting by human,and environmental fluctuations is *** an optimal management strategy ultimately reduces to solving a 2D Hamilton–Jacobi–Bellman equation,which is performed with a finite element *** application to a Japanese river environment successfully computes the optimal management strategy that is consistent with the *** sensitivity analysis of the presented mathematical model is also performed for comprehension of dependence of the optimal strategy on the model parameters.

关键词： Optimal fishery resources management inland fishery resources waterfowl Hamilton-Jacobi-Bellman equation finite element approximation.

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Species richness estimations of the megadiverse scuttle fly genus Megaselia （Diptera： Phoridae） in a wildfire-affected hemiboreal forest

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Insect Science 2011年第3期18卷 325-348页

作者： James Bonet Sven-Olof Ulefors Bert Viklund Thomas Pape Department of Zoology Stockholm University Stockholm Fargerivagen 9 Alsterbro Sweden Natural History museum of Denmark Copenhagen Denmark Swedish museum of Natural History Stockholm Sweden

The species richness of the scuttle fly （Diptera： Phoridae） genus Megaselia was estimated by various non-parametric estimators from EstimateS, Species Prediction And Diversity Estimation （SPADE） and Ws2m, based on material from a Swedish hemiboreal forest area recently affected by major wildfires, Yyresta National Park and Nature Reserve （TNPNR）, south of Stockholm. A total of 21 249 individuals were collected in Malaise traps, of which males constituted 16 976 and females 4 273. The analysed dataset represents 37 samples containing 18 549 specimens sorted into 330 species （184 described, 146 are either undescribed or of unsettled taxonomic status）. It was not possible to estimate the total species richness using all samples due to heterogeneity caused by inclusion of different communities and temporal incoherencies between samples within and between years. Even with material obtained from a sampling program that was not designed for species richness estimates, it was possible to obtain reliable results when sample heterogeneity was minimized. By dividing the data into community-specific datasets - for bog, forest and wildfire - it was possible to obtain asymptotic curves for the smaller of the two wildfire datasets. A total estimate of 357~439 （95% CI） was attained by using the smaller wildfire dataset and adding the 85 unique species from the samples not included in the estimation analysis. TNPNR has one of the richest known scuttle fly communities in Europe, consisting of almost 50% of the currently named Megaselia species; 48 of these species are reported as new records for Sweden in this study.

关键词： hemiboreal forest morphospecies sample heterogeneity scuttle flies species richness estimations

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Intercontinental and intracontinental biogeography——patterns and methods

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Journal of Systematics and Evolution 2009年第5期47卷 327-329页

作者： Stefanie M. ICKERT-BOND UA museum of the North Herbarium and Department of Biology and Wildlife University of Alaska Fairbanks

The study of biogeography has benefited from the exponential increase of DNA sequence data from recent molecular systematic studies

关键词： DIVA patterns and methods

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A new resource for China

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Zoological Research 2016年第1期37卷 2-3页

作者： David B.WAKE the Graduate School in Integrative Biology the museum of Vertebrate Zoology,university of California at Berkeley museum of Vertebrate Zoology University of California. wakelab@berkeley.edu.

n my country, as elsewhere nformation about animals. n the world, when one wants such as amphibians, one typically seeks out a field guide or a monograph. As the amphibian fauna around the world has grown （from about 4 000 species in 1985 to nearly 7 500 today）, the books, too, have become thicker, heavier, and more and more unwieldy. These books might contain features to assist identification-- written descriptions, keys, photographs and maps of the polygon variety and encompass known sites of occurrence. But the books quickly become out-of-date as knowledge increases and they rarely have information about phylogenetic relationships or display trees. But, we now live in a digital age, and young people, in particular, view books as old-fashioned and inadequate for their needs. The time is ripe for a new approach.

关键词： A new resource for China maps more

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The Flight Dynamics of Tapejara,a Pterosaur From the Early Cretaceous of Brazil with a Large Cranial Crest

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Acta Geologica Sinica(English Edition) 2012年第6期86卷 1377-1388页

作者： Sankar CHATTERJEE R.Jack TEMPLIN Department of Geosciences Museum of Texas Tech University Aerodynamic Laboratory National Research Council

Tapejara wellnhoferi, a small azhdarchoid pterodactyloid from the Early Cretaceous Santana Formation of Brazil, provides critical information about the aerodynamic function of its spectacular head crest. The cranial crests in pterodactyloids were sexually dimorphic and are thought to have evolved in adult males in response to female mate choice. However, the location of cranial crests in front of the center of gravity would create instability in the yaw axis during flight and may seem like a handicap. Vertically aligned webbed feet probably suppressed the yawing rotations and instability from the crest. Here we show that the crest functioned as a front rudder to make agile turn and mediate flight control. A computer simulation model suggests that Tapejara had a large excess of muscle power available above the power required for continuous flapping flight. It could easily takeoff from a perch, ground, or water surface and land safely on the ground. It was an excellent glider with a gliding angle close to 4~ and a cruising speed of 27 km/h. Tapejara could soar efficiently on the windward side of cliffs or circle on rising thermals over tropical waters for efficient long-distance flight. Various control surfaces in the wings of Tapejara analogous to the slat, aileron, elevator, fin, rudder, and horizontal stabilizer of an aircraft made pterodactyloids versatile flyers.

关键词： Tapejara Cretaceous pterodactyloids cranial crest flight Brazil

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A New Species of Odorrana Inhabiting Complete Darkness in a Karst Cave in Guangxi, China

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Asian Herpetological Research 2015年第1期6卷 11-17页

作者： Yunming MO Weicai CHEN Huaying WU Wei ZHANG Shichu ZHOU Natural History museum of Guangxi School of Life Sciences East China Normal University

A new species of the genusOdorrana is described from a completely dark karst cave of northeastern Guangxi, southern China. The new species,Odorranalipuensissp. nov., can be distinguished from its congeners by a combination of the following characters： medium size （SVL： 40.7–47.7 mm in males, 51.1–55.4 mm in females）;tips of all but ifrst ifnger expanded with circummarginal grooves; smooth, grass-green dorsum with irregular brown mottling; pineal body invisible; throat to upper abdomen with gray mottling; dorsal surfaces of limbs with brown bands; dorsolateral fold absent; tiny spinules on lateral body, temporal region, and anterior and posterior edge of tympanum;white nuptial pad present on ifnger I; males lacking vocal sacs; females having creamy yellow eggs, without black poles. Uncorrected sequence divergences ***. nov. and all homologous 16S rRNA sequences ofOdorrana available on GenBank is equal to or greater than 4.9%. Currently, the new species is only known from the type locality.

关键词： Odorrana lipuensis sp. nov. karst cave Guangxi southern China

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A fossil-calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America

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Journal of Systematics and Evolution 2009年第5期47卷 444-456页

作者： Stefanie M.ICKERT-BOND Catarina RYDIN Susanne S.RENNER university of Alaska UA Museum of the North Herbarium and Institute of Arctic Biology Institute of Systematic Botany University of Zurich university of Munich Systematic Botany and Mycology

Ephedra comprises approximately 50 species,which are roughly equally distributed between the Old and New World deserts,but not in the intervening regions(amphitropical range).Great heterogeneity in the substitution rates of Gnetales(Ephedra,Gnetum,and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra,such as the timing of the Beringian disjunction in the genus and the entry into South ***,we use data from as many Gnetales species and genes as available from GenBank and from a recent study to investigate the timing of the major divergence *** of the tradeoff between the amount of missing data and taxon/gene sampling,we reduced the initial matrix of 265 accessions and 12 loci to 95 accessions and 10 loci,and further to 42 species(and 7736 aligned nucleotides) to achieve stationary distributions in the Bayesian molecular clock *** from a relaxed clock with an uncorrelated rates model and fossil-based calibration reveal that New World species are monophyletic and diverged from their mostly Asian sister clade some 30 mya,fitting with many other Beringian *** split between the single North American and the single South American clade occurred approximately 25 mya,well before the closure of the Panamanian ***,the biogeographic history of Ephedra appears dominated by long-distance dispersal,but finer-scale studies are needed to test this hypothesis.

关键词： biogeography Ephedra relaxed molecular clock dating uncorrelated rates model.

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Plant food sources and stone tools' function at the site of Shunshanji based on starch grain analysis

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Science China Earth Sciences 2016年第8期59卷 1574-1582页

作者： YANG YuZhang LI WeiYa YAO Ling CHENG ZhiJie LUO WuHong ZHANG JuZhong LIN LiuGen GAN HuiYuan YAN Long Department for the History of Science and Scientific Archaeology University of Science and Technology of China Faculty of Archaeology Leiden University Institute of Archaeology Nanjing Museum

The upper-middle Huai River valley(HRV) is located in the transition zone in the middle of eastern China. Previous studies have shown that the past populations in the upper HRV obtained plant food through gathering and cultivation of both rice and millet during the middle Neolithic. However, for the middle HRV it is not very clear what methods were used by humans to obtain plant food in that time. In this paper, starch grain analysis was carried out on 17 stone tools and 29 cauldron pottery sherds unearthed at Shunshanji(8.5–7.0 kyr BP), which is known as the earliest Neolithic site in the middle HRV excavated so far. Here, ancient starches from Coix lacryma-jobi, Triticeae, Oryza sativa, Trichosanthes kirilowii and one unidentified specie were recovered. This study contributes to the limited knowledge of food strategies as observed in the middle HRV. It demonstrates that both gathering and cultivation of rice took place during the middle-Neolithic. Among the identified species, Coix lacryma-jobi appears to have been the main plant food at Shunshanji. Moreover, it is clear that Oryza sativa was not consumed as much as other plant species according to the occurrence frequency of different starch grains. Starch grains were also found on the used surfaces of grinding stone implements as well as pestles, which means that these stone tools were used for food processing. In addition, axes from Shunshanji may also have been used for food processing as well as wood working because starches were also found on the edge of axes. Information about subsistence strategies and tool use at Shunshanji will also be helpful to understanding the utilization of plants and agricultural development in the middle HRV during the early-middle Neolithic period.

关键词： Shunshanji Starch grain analysis Utilization of plants Development of agriculture Function of stone tools

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Toward understanding Cretaceous climate An updated review

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Science China Earth Sciences 2017年第1期60卷 5-19页

作者： William W. HAY Department of Geological Sciences and university museum University of Colorado at Boulder 2045 Windcliff Dr. Estes Park CO 80517 USA

New data and ideas are changing our view of conditions during the *** of the continents was lower than originally thought,eliminating the'cold continental interior paradox'of fossils of plants that could not tolerate freezing occurring in regions indicated by climate models to be well below freezing in *** controversy over the height of Cretaceous sea levels has been resolved by knowledge of the effects of passage of the subducted slab of the Farallon Plate beneath the North American *** cause of shorter term sea level changes of the order of 30 to 50 meters is not because of growth and decay of ice sheets,but more likely the filling and release of water from groundwater reservoirs and lakes although there may have been some ice in the Early and latest *** dioxide was not the only significant greenhouse gas;methane contributed significantly to the warmer *** of very warm tropical ocean temperatures(>40℃)have implications for the nature of plant life on land limited by Rubisco *** land surfaces were much wetter than has been thought,with meandering rivers and many oxbow lakes providing habitat for large dinosaurs.A major rethinking of the nature of conditions on a warmer Earth is underway,and a new suite of paleoclimate simulations for the Cretaceous is needed.

关键词： Cretaceous Paleogeography Paleotopography Sea level Greenhouse Paleohydrology Paleoclimate

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Food Habits and Distribution of the Lake Taal Sea Snake(Hydrophis semperi Garman 1881) and the Sympatric Little File Snake(Acrochordus granulatus Schneider 1799) in Lake Taal, Philippines

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Asian Herpetological Research 2014年第4期5卷 255-262页

作者： Vhon Oliver S.GARCIA Rey Donne S.PAPA Jonathan Carlo A.BRIONES Norman MENDOZA Noboru OKUDA Arvin C.DIESMOS The Graduate School University of Santo Tomas Research Center for the Natural and Applied Sciences University of Santo Tomas Department of Biological Sciences University of Santo Tomas Department of Science and Technology Philippine Nuclear Research Institute Center for Ecological Research Kyoto University Herpetology Section Zoology Division National Museum of the Philippines

Our knowledge about the food habits of sea snakes and how it is associated with their distribution has seen much development through its description across a number of species available through published literature except for the key threatened species such asHydrophis semperi. This paper aims to describe the food habits ofH. semperi through gut content and stable isotope analyses. We also compared data with the Little File Snake,Acrochordus granulatus, sympatric withH. *** captures ofH. semperi suggest that the sea snake tends to occur in the littoral zones and the shallower portions of the limnetic zone. Gut content analysis ofH. semperi have shown that gobies and eels are primary prey items. Halfbeaks （Family Hemiramphidae） were recorded as one of the Lake Taal Sea Snake＇s prey items which is considered as a new prey record for sea snakes. These extracted gut contents are conifrmed to be the temporal food preference ofH. semperi given our detected stable isotope signatures. It appears thatA. granulatus and H. semperi share common prey items suggesting possible diet overlap and resource *** study reports the ifrst account of the endemic Lake Taal Sea Snake＇s distribution and food habits which poses implications towards its conservation as it occurs in a restricted ecosystem that has undergone considerable habitat alteration.

关键词： freshwater diet feeding Hydrophis semperi Hydrophiidae

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