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1.
《Palaeoworld》2015,24(4):383-388
The early history on the discovery of the first Chinese crinoid calyx of “Cupressocrinus abbreviatus” (now Halocrinites schlotheimii Steininger, 1831) remains unclear. The first record of “C. abbreviatus” was reported by Fritz Frech in 1911. It was included in the fifth and the last volume of the series titled China by the German traveler and explorer Ferdinand Freiherr von Richthofen. The cover page, title page, and prologue are informative; thus, they are explained and translated in detail. Richthofen's specimen is still the oldest documented cupressocrinitid calyx known in China today. Discovery of a second cupressocrinitid specimen confirms the existence of this family in China. Current taxonomic positions of the Chinese specimens are discussed. 相似文献
2.
One new genus of the spider subfamily Coelotinae, Flexicoelotes
gen. n., with five new species is described from southern China: Flexicoelotes
huyunensis
sp. n. (female), Flexicoelotes
jiaohanyanensis
sp. n. (male and female), Flexicoelotes
jinlongyanensis
sp. n. (male and female), Flexicoelotes
pingzhaiensis
sp. n. (female), Flexicoelotes
xingwangensis
sp. n. (male and female). 相似文献
3.
Longleaf pine (Pinus palustris) savanna is a biodiverse ecosystem native to the southeastern United States. Due to fire suppression and timber harvest, longleaf pine has declined to 3% of its original range. The extant forest provides habitat for many threatened and endangered species, including the endangered Red-cockaded Woodpecker (Picoides borealis; RCW), a cavity-nesting bird that co-evolved with fire-maintained forest, resulting in savanna-like old-growth forest as the bird’s preferred habitat. Our study site, the Oakmulgee Ranger District of the Talladega National Forest, harbors the largest RCW population in Alabama and is managed with an emphasis on RCW conservation. The United States Forest Service (USFS) also manages the Oakmulgee for uses such as wildlife conservation, recreation, and timber harvest. Despite efforts to restore RCW habitat and install artificial cavities in the Oakmulgee, the number of RCW groups has not exceeded 123, although the Recovery Plan objective is 394 groups. Our project was motivated by the USFS expressing interest in determining why the RCW population has not exceeded 123 groups. We proposed using structured decision making (SDM) with the USFS and other stakeholders to address this problem. Our goals were to explicitly define management objectives, build a Bayesian belief network with a model of how decision alternatives are believed to affect management objectives, and use a sensitivity analysis to determine the part of the model to which RCW population growth was most sensitive. Therefore, results from the analysis were expected to give insights into 1) ecological factors limiting RCW population growth, 2) how management can overcome these limits, plus 3) the relative expected ability of different decision alternatives to satisfy multiple objectives in addition to increasing RCW group number. We held four SDM workshops with representatives from the USFS, the Animal and Plant Health Inspection Service, the Longleaf Alliance, the Birmingham Audubon Society, and local residents. Stakeholder objectives consisted of maximizing the following: RCW group number, forest health, recreational enjoyment, community economic health, and aesthetics. Cavity insert installation had the greatest probability of increasing the number of RCW groups. The number of RCW groups was most affected by cavity availability, adult survival, reproductive output, food availability, and herbaceous understory. Prescribed burning was most likely to meet the combination of stakeholder objectives, followed by midstory removal. Our findings suggest that cavity installation efforts may need to be increased in the Oakmulgee to increase RCW group number. Also it could be beneficial to investigate how RCWs select cavity tree locations with the goal of increasing the chance that RCWs use artificial cavities to form new groups. The Bayesian belief network provided insights into factors limiting RCW population growth and how management can overcome these limits. The Bayesian belief network also can be used to prioritize management methods in the Oakmulgee given stakeholder objectives and time constraints. 相似文献
4.
Alan B. Darlington Anna Halinska James F. Dat T. J. Blake 《Trees - Structure and Function》1997,11(4):223-228
Plant responses to saturation vapour pressure deficit (SVPD) were studied by subjecting black spruce [Picea mariana (Mill) B.S.P.] and jack pine seedlings (Pinus banksiana Lamb.) to humid (0.3 – 0.8 kPa) or dry (2.0 – 2.5 kPa SVPD) regimes for 4 weeks using a computer-controlled environmental
system to control diurnal variation in SVPD. Dry matter accumulation in needles was not altered by increasing SVPD. However,
root growth declined by 60% which increased shoot to root ratio and reduced total seedling dry weight in both black spruce
and jack pine. Relative growth rate of jack pine also declined to about half the rate of plants grown under humid conditions.
In situ root marking studies showed that the decline in root growth of jack pine under the high SVPD was the result of reduced
lateral root initiation, whereas root elongation was unaffected by humidity. A 4-week exposure to dry air increased abscisic
acid (ABA) levels in needles, but not roots, of jack pine whereas ABA levels in black spruce were not altered. A short (3-day)
exposure failed to increase needle ABA levels in either species. These results suggest that the responses of conifers to dry
air were not the result of ABA accumulation.
Received: 24 March 1996 / Accepted: 30 May 1996 相似文献
5.
Efforts to restore ponderosa pine ecosystems to open, park‐like conditions that predominated prior to European‐American settlement result in altered stand structure and increased landscape heterogeneity, potentially altering habitat suitability for invertebrates and other forest organisms. We examined the responses of two butterfly species, Colias eurytheme and Neophasia menapia, to microclimatic changes at structural edges created by experimental restoration treatments in northern Arizona. We monitored microclimate, including air temperature, light intensity, and vapor pressure deficit (VPD), on several mornings during butterfly releases. We placed adult butterflies at east‐ and west‐facing edges approximately one half‐hour before dawn to determine their behavioral response to microclimatic differences between east‐ and west‐facing edges. After sunrise, all three microclimatic variables were higher at east‐facing edges, and the difference in microclimate between the two edge orientations increased through early morning. For both species, butterflies placed at east‐facing edges flew earlier than butterflies at west‐facing edges. Colias eurytheme, an open‐habitat species, tended to move toward the treated forest during initial flight, while movements of Neophasia menapia, a forest‐dwelling species, did not differ from random flight. Our results indicate that butterflies respond to microclimatic factors associated with restoration treatments, while responses to structural changes in habitat vary among species, based on habitat and food plant preferences. These changes in forest structure and microclimate may affect the distribution of many mobile invertebrates in forested landscapes undergoing restoration treatments. 相似文献
6.
Loblolly pine (Pinus taeda L.) produces an induced defensive hypersensitive response in inner bark colonized by the southern pine beetle, Dendroctonus frontalis Zimm. (Coleoptera: Scolytidae), and its associated fungi. Adult beetles forced to colonize the induced response tissue in a laboratory study constructed galleries that were the same length as adults boring in normal phloem. However, each female laid fewer eggs in the induced tissue. Larval and pupal mortality were also higher in this tissue when compared to surrounding phloem. Beetles colonizing trees in response to pheromone baits constructed less gallery and laid fewer eggs in induced tissue than in surrounding normal phloem. These results suggest that the lesions produced by the induced defense system in conifers may not only contain the growth of fungi inoculated into trees during the attack phase of beetle colonization, but may also affect survival of bark beetle progeny.
Résumé Une réaction hypersensible de défense a été induite dans les couches profondes de l'écorce de P. taeda colonisée par D. frontalis et le champignon qui lui est associé. Au laboratoire, des adultes, contraints de coloniser les tissus où une réaction hypersensible e été induite, ont foré des galeries de même longueur que celles creusées dans du phloème sain. Cependant les femelles ont pondu moins d'oeufs dans les tissus induits; les mortalités larvaires et nymphales étaient aussi plus fortes dans ce tissu que dans le phloème voisin. Les scolytes, ayant colonisé les arbres après attraction par des pièges à phéromones, forent moins de galeries et pondent moins d'oeufs dans le tissu induit que dans le phloème sain voisin. Ces résultats suggèrent que les lésions, provoquées par le système de défense induit des conifères, peuvent non seulement limiter la croissance du champignon inoculé dans l'arbre au cours de la colonisation des scolytes, mais aussi affecter la survie des descendants dans l'écorce.相似文献
7.
8.
9.
D. R. Gustafsson L. Lei K. Luo X. Chu X. Zhao Q. Zhang F. Zou 《Medical and veterinary entomology》2019,33(3):407-419
In total, 366 birds representing 55 species in 24 families and eight orders, were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera) in two high‐altitude localities in Yunnan Province, China. In Ailaoshan, almost all of the birds examined were resident passeriforms, of which 36% were parasitized by chewing lice. In Jinshanyakou, most birds were on migration, and included both passerine and non‐passerine birds. Of the passerine birds caught in Jinshanyakou, only one bird (0.7%) was parasitized by chewing lice. The prevalence of Myrsidea and Brueelia‐complex lice on birds caught in Ailaoshan was higher than in previous reports. Of the chewing lice identifiable to species level, three represent new records for China: Actornithophilus hoplopteri (Mjöberg, 1910), Maculinirmus ljosalfar Gustafsson & Bush, 2017 and Quadraceps sinensis Timmermann, 1954. In total, 17 new host records are included, of which we describe two as new species in the Brueelia‐complex: Guimaraesiella (Cicchinella) ailaoshanensis sp. nov. ex Schoeniparus dubius dubius (Hume, 1874) and G. (C.) montisodalis sp. nov. ex Fulvetta manipurensis tonkinensis Delacour & Jabouille, 1930. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:9FC3D8EE‐2CED‐4DBE‐A1DB‐471B71260D27 . 相似文献
10.
Foliar uptake and release of inorganic nitrogen compounds in Pinus sylvestris L. and Picea abies (L.) Karst. 总被引:2,自引:0,他引:2
E.J. WILSON 《The New phytologist》1992,120(3):407-416