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1.
Three desert Artemisia tridentata communities in Rush Valley, Utah, were trapped for small rodents during the summer of 1970, and population densities were estimated for each population category using Lincoln's index. Animals were weighed and rodent biomass calculated by species throughout the summer. Population, biomass, and other data were then analyzed to gain an understanding of the community relationships of the three study areas to each other as well as to the A. tridentata community types of the Great Basin. Peromyscus maniculatus, Eutamias minimus, and Reithrodontomys megalotis were common to area 1, whereas P. maniculatus, E. minimus, and Perognathus parvus were common to areas 2 and 3. The peak estimated standing crops were 182.8 (74.0). 143.1 (57.9), and 129.7 g/acre (52.5 g/ha) for areas 2, 1, and 3 respectively. The population and biomass of area 2 peaked in midsummer, area 1 early summer, and area 3 late summer.  相似文献   

2.
The sagebrush biotype is the largest in the western United States. This vast sagebrush community is thought to harbor equally vast and diverse arthropod communities, but these remain little explored. Our objective was to examine the diversity, abundance, and seasonal phenology of arthropod taxa found on the dominant shrub of the sagebrush ecosystem, big sagebrush ( Artemisia tridentata ). We wanted to improve understanding of this little-studied arthropod assemblage that may play significant roles in the dynamics of sagebrush populations and the sagebrush ecosystem. We sampled free-living and gall-forming arthropods from a stratified random sample of sagebrush plants at the Barton Road Ecological Research Area, Idaho, resulting in a sample of over 8000 individuals and 232 morphospecies. Species richness and abundance declined from May to August, and abundance of most taxa similarly declined over the summer. A few taxa, including Acari (mites), were notably more abundant in August. Fluid feeders were the most diverse and abundant free-living feeding guild during all months and comprised up to 79% of morphospecies. The gall formers included 4713 individuals of 12 species of gall flies ( Rhopalomyia spp.), primarily (97%) R. ampullaria. Abundance of galls increased from small to large (presumably young to old) plants. Overall, A. tridentata was host to a high diversity of arthropods, some of which have potential to cause or mitigate significant damage to their host plant. Arthropods seem likely to have the greatest impact on sagebrush early in the growing season, when they are most diverse and abundant. Documentation of the full diversity of arthropods associated with sagebrush required samples taken throughout the growing season, but a single sample early in the growing season captured a high proportion of taxa.  相似文献   

3.
This study compared the abilities of two cool-season bunchgrasses to extract moisture from a drying soil and compared photosynthetic and stomatal responses of the two species as soil moisture supplies were depleted. When grown in 49-L pots in a greenhouse, Leymus cinereus extracted more water from the soil and maintained higher gas exchange rates to lower absolute amounts of soil water than did Agropyron desertorum . The soil water content at the lower limit of extraction was 10.3% for L. cinereus and 13.3% for A. desertorum . When soil moisture was expressed as extractable soil water, there was little difference between the species in pattern of water use. Both species maintained high stomatal conductances (g w ) and photosynthetic rates (A) until extractable soil moisture was reduced to about 15%. For field-grown plants under severe water stress, A was higher in L. cinereus than in A. desertorum at comparable leaf water potentials. The relationship between A and g w was similar for the two species; higher A in L. cinereus was a consequence of higher g w . Thus, higher A in L. cinereus is achieved through some sacrifice of water-use efficiency.  相似文献   

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5.
Patterns of colonization by macroinvertebrates were examined in two streams that differ in flow regime: a snowmelt system and a mesic groundwater system. Experiments were conducted during spring runoff, summer baseflow, and winter baseflow using artificial substrata. Colonization patterns reflected seasonal changes in benthic macroinvertebrate assemblages and life histories in each stream. The density and biomass of benthic organisms were approximately 3X greater in winter than in either spring or summer for both streams. Similarly, colonization was greater in winter than in spring or summer for both streams. In spring, colonization patterns were different between streams, with colonization being imperceptible in the snowmelt stream. Macroinvertebrate abundance fluctuated during the summer colonization experiment at both sites, resulting from a complex interplay among population emergence, recruitment, and/or movement. Assemblages in the snowmelt system primarily comprised mobile or ruderal taxa, such as Beatis tricaudatus and Chironomidae, whereas relatively sessile taxa, such as Glossoma nigrior , were predominant in the mesic groundwater system. Seasonal patterns of colonization differed among stream types primarily because of the profound interplay of flow regime and temperature on benthic community structure and organism life history.  相似文献   

6.
Herbaceous vegetation pattern and soil properties around individual Juniperus pinchotii Sudw. trees were studied on a grazed and a relict grassland in western Texas. Herb standing crop and soil samples were obtained under the canopy, at canopy edge, and beyond the canopy edge of three to five trees on each of four dates. Standing crop was lowest midway between the bole and canopy edge. Soil organic matter was highest under juniper canopies on both sites. Soil pH and P were not related to distance from tree bole on either site. Herbaceous pattern from under the canopy to canopy edge apparently depended primarily on individual tree size. However, trees had little influence on herbaceous vegetation pattern 3-5 m beyond canopy edge, a response attributed to distance-independent interaction between J. pinchotii and herbaceous vegetation. Given a shallow soil underlain by indurated caliche and tree densities ranging from 288 (relict size) to 2123 (grazed site) trees/ha, the interaction between J. pinchotii and herbaceous vegetation did not change over a distance of 3-5 m from tree canopy edge in our study area.  相似文献   

7.
An earthworm inventory was conducted on three islands (Hon Tre, Lai Son and An Son) in the southernmost part of Vietnam. A total of 13 species and subspecies belonging to four genera and two families were collected from 49 sampling sites. The genus Metaphire Sims & Easton, 1972 is dominant with six species and subspecies, Metaphire anomala (Michaelsen, 1907), Metaphire bahli (Gates, 1945), Metaphire houlleti (Perrier, 1872), Metaphire mangophila (Nguyen, 2011), Metaphire kiengiangensis Nguyen & Trinh, 2015, Metaphire peguana laisonensis subsp. nov. Two new species, Polypheretima dorsotheca sp. anov. and Polypheretima insularis sp. nov., and a new subspecies Metaphire peguana laisonensis subsp. nov. are described. Additionally, Amynthas alteradamae (Michaelsen, 1934) and Amynthas tertiadamae (Michaelsen, 1934) are re-described based on fresh material. An identification key to species is also provided.

http://zoobank.org/urn:lsid:zoobank.org:pub:4EA4C2C0-BEC2-45BF-8B72-388302A53F51  相似文献   


8.
ABSTRACT

Two species of bopyrid isopods of the Bopyrinae subfamily are recorded from new localities and hosts in northeastern Brazil. Parabopyrella lata (Nierstrasz and Brender à Brandis, 1929) was recorded from the state of Ceará, found for the first time parasitising the caridean shrimp Alpheus packardii Kingsley, 1880. In addition, Probopyrus cf. pandalicola (Packard, 1879) is recorded from the state of Bahia, parasitising the palaemonid shrimp Palaemon northropi (Rankin, 1898). Taxonomic comments are provided for each species.  相似文献   

9.
《Journal of Natural History》2012,46(9):1849-1863
Based on morphometric and allozyme data of a large sample of black-chinned tilapia, Sarotherodon melanotheron, originating from over its entire geographical distribution range, the subspecific classification of this species has been revised. One subspecies, S. m. paludinosus, is synonymized with S. m. heudelotii. The validity of another subspecies, S. m. leonensis, is questioned. The remaining three subspecies, S. m. melanotheron, S. m. heudelotii and S. m. nigripinnis are clearly distinguished as separate taxa.  相似文献   

10.
《Journal of Natural History》2012,46(47-48):2897-2918
Leaf-litter thrips were much more common and diverse in dry sclerophyll forest than in wetter forest types in subtropical southeast Queensland, Australia. In dry sclerophyll forest, the species composition of thrips in leaf-litter was strongly differentiated from the thrips fauna associated with bark of the trees Eucalyptus major and Acacia melanoxylon (4 of 34 species in common). The species composition of bark-dwelling thrips was similar across the two tree species and also across two eucalypts with different bark types, Eucalyptus major (flaky) and Eucalyptus siderophloia (rough). The diversity of thrips from the leaf-litter was not differentiated across all of these tree species. Virtually all thrips collected were Phlaeothripidae, subfamilies Idolothripinae and Phlaeothripinae. Idolothripinae were associated almost exclusively with leaf-litter, but Phlaeothripinae were in leaf-litter and bark. The association of fungal-feeding thrips with dry sclerophyll forest raises questions about their ecological requirements and the role they play in nutrient cycling.  相似文献   

11.
Yearly variation in numbers of cones produced by western white pine was found to affect the population level of the mountain pine cone beetle. In years when cone production is moderate to heavy, beetle populations increase. Increasing beetle populations are ultimately limited by poor cone crops, which increase competition for nutrients and oviposition sites. Variability in western white pine cone production is regarded as the most important factor regulating populations of the mountain pine cone beetle.     相似文献   

12.
Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A general analysis of the populations of Crotaphytus wislizeni in the Great Basin is presented. A new subspecies, C. wislizeni maculosus, for the Lahontan Basin, Nevada, is described and comparisons of color pattern, some scale patterns, and skull measurements are presented.  相似文献   

13.
14.
15.
Two genera, 12 species and one species complex of the polychaete family Glyceridae are described and figures from the North East Atlantic and Mediterranean. Diagnostic taxonomic features are described and keys to genera and species are included. Material from other parts of the world is also considered where relevant to the taxonomy of the species concerned. Of the 12 recorded species, one is reestablished for European waters after submersion in synonomy, a species complex is described and two new species are erected.  相似文献   

16.
《Journal of Natural History》2012,46(29-30):1867-1893
The contents of swollen-thorn domatia of three Acacia species are given. Lepidoptera bred from swollen thorns of Acacia are listed; two new genera, Endotera gen. nov. and Kenyatta gen. nov., and six new species: Phthoropoea chalcomochla sp. nov., Endotera nodi sp. nov., Hystrichophora vittana sp. nov., Hystrichophora griseana sp. nov., Hystrichophora bopprei sp. nov. and Kenyatta iodes sp. nov., are described.  相似文献   

17.
The gall-forming psylloid fauna associated with the temperate Neotropical plant genus Schinus (Anacardiaceae) is revised, and keys are provided for adults, larvae and galls. Fourteen species are recognized in the genus Calophya (Calophyidae), 10 of which are described as new; C. gallifex and C. schini are reinstated from former synonymy with C. rubra. An additional closely related new species, C. clavuligera sp. n., is described from Lithrea spp. In the genus Tainarys (Psyllidae, Rhinocolinae), six species are recognized and, for five of these, Schinus species are confirmed hosts. Two of them are described as new and one is recombined from Leurolophus. A new Leurolophus species is described from Lithrea molleoides. Based on a cladistic analysis Pelmatobrachia, Microceropsylla and Neocalophya are synonymized with Calophya, producing five new and one revised species combinations as well as one nomen nov. A list of the 59 currently recognized species is provided with information on synonymy, distribution and host plants. The cladistic analyses suggest that the Schinus inhabiting calophyids form two monophyletic groups, the C. rubra and C. hermicitae groups, respectively. A discriminant analysis of 15 variables for both males and females provides morphometric characters for separating the morphologically very homogenous adults of the C. rubra group. The phylogenetic relationships of the Rhinocolinae are re-evaluated, and the genera Tainarys and Leurolophus are redefined. Notophyllura is transferred from the Euphyllurinae to the Rhinocolinae. Tainarys forms the sister group of Leurolophus + Notophyllura. Based on mapped distributions four areas of endemism (distribution) are defined: A (Eastern temperate South America), B (Central and Southern Chile, including adjacent parts of Argentina), C (Central Argentina) and D (Peru, Far Northern Chile, and Eastern Bolivia). Cladistic biogeographical analyses with TAS, COMPONENT and an algorithm by Enghoff yielded the general area cladogram (A +(C +(B +D))); the one calculated with BPA differed in the position of D: (D +(A +(B +C))). The reconstruction of vicariant events using a protocol by Hovenkamp, corroborates the former general area cladogram, which is compared to competing hypotheses. The history of dispersal and vicariance events is reconstructed with the programme DIVA. Evidence for cospeciation of Schinus with its associated psylloids is evaluated with COMPONENT and TREE MAP. The likelihood for cospeciation is high in the Calophya hermicitae group, but low in the Calophya rubra group and in Tainarys. The gall shape depends partly from the psylloid, partly from the Schinus phylogeny.  相似文献   

18.
In this study, 192 samples were collected and analyzed from diverse water bodies in the Tiantong National Forest Park and Dongqian lake in Zhejiang Province, China. Twenty living ostracod species were identified, belonging to four families, eight subfamilies and 15 genera. Among them, two species are new, belonging to the genera Ilyocypris and Schellencandona; seven species, including Dolerocypris ikeyai Smith and Kamiya, 2006, Pseudocandona abei Smith and Janz, 2008, Stenocypris hirutai Smith and Kamiya, 2006, S. viridis Okubo, 1990, Tanycypris alfonsi Nagler et al., 2014, T. centa Chang et al., 2012 and Vestalenula cornelia Smith et al., 2006, are new records for China; nine species are reported only from Asia: Candonopsis (Candonopsis) transgrediens Brehm, 1923, Chrissia dongqianhuensis Kong et al., 2014, Dolerocypris ikeyai Smith and Kamiya, 2006, Ilyocypris dui n. sp., Pseudocandona abei Smith and Janz, 2008, Schellencandona dui n. sp., Stenocypris hirutai Smith and Kamiya, 2006, S. viridis Okubo, 1990 and Vestalenula cornelia Smith et al., 2006. Of the above species, the two new species, Schellencandona dui n. sp. and Ilyocypris dui n. sp., are described and illustrated, and Stenocypris viridis is re-described.

www.zoobank.org/urn:lsid:zoobank.org:pub:2D679051-CBA2-4B09-BCF0-E0152EBC2694  相似文献   


19.
《Journal of Natural History》2012,46(11-12):737-768
A list of newly collected and identified oribatids from Kenya is presented, two of them represent new genera; Sceletoppia gen. nov. (Oppiidae) and Mahnertozetes gen. nov. (Haplozetidae). Twelve species, belonging to the families Steganacaridae, Lohmanniidae, Tetracondylidae, Microzetidae, Zetomotrichidae and Galumnidae are new to science. Taxonomical notes on two other species are given.  相似文献   

20.
《Journal of Natural History》2012,46(12):1739-1765
Six species of the genus Antarctoscyphus Peña Cantero, García Carrascosa and Vervoort, have been studied, two of which are new to science (Antarctoscyphus admirabilis sp. nov. and A. fragilis sp. nov.). The material studied originates from the Weddell Sea and was collected by several French and German Antarctic expeditions with the R.V. Polarstern. Each species is described and figured, the systematic position amongst allied species discussed and available data concerning autecology and geographical distribution given. The type material of two badly known species, A. grandis (Blanco) and A. gruzovi (Stepan'yants), has been re-examined, re-described and figured. A comparative table listing main features of known species of Antarctoscyphus is presented. Finally, a general survey of biogeographical distribution of the known species is given.  相似文献   

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