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891.
892.
在广西柳州市选择7个本地树种和15个外地树种进行引种试验,测定树种的光合效率、净化空气效率、生长量等指标,评价树种的适应性和抗逆性.结果选择出9个柳州市最佳的行道树种:广玉兰(Magnolia grandiflora L.)、狭叶杜英(Elaeocarpus lanceaefolius Roxb.)、乐昌含笑(Michelia chapensis Dandy)、大叶樟[Cinnamomum parthenoxylon (Jack) Nees]、海南蒲桃[Syzygium cumini (L.) Skeels]、美丽异木棉(Chorisia speciosa A.St.Hil.)、菩提树(Ficus religiosa L.)、仪花(Lysidice rhodostegia Hance)和栾树(Koelreuteria paniculata Laxm.),其中:大叶樟、海南蒲桃、仪花可作建群种,在营建行道树群落时作上层乔木的主体. 相似文献
893.
衡水湖自然保护区藻类植物资源初步研究 总被引:4,自引:0,他引:4
首次报道了衡水湖国家级湿地自然保护区藻类植物的种类组成、生态类群及常见群落.经初步调查和鉴定,衡水湖国家湿地自然保护区藻类植物共有9门、11纲、22目、31科、59属、119种(含种下分类单位),4种生态类群和8个常见藻类群落.主要类群中以绿藻门最多,共计49种,占保护区藻类总种数的4 1.2%;其次是硅藻门,31种(含1变种)占26.1%;再次是蓝藻门,22种(含1个变型)占18.5%.对衡水湖自然保护区水体环境质量、藻类资源进行了初步评价. 相似文献
894.
张学范 《南京林业大学学报(自然科学版)》1992,35(1):53
<正>本文记述了采自皖南竹链蚧属蚧虫一新种Bambusaspis huichowensis sp.nov.。 相似文献
895.
针对目前我国生态系统关键种生存受到严重威胁的问题,阐述了关键种的概念、起源及关键种在生态系统中的重要地位。同时从关键种在生态系统中所具有的理论和实践价值等多角度进行了分析,以及对怎样有效保护生态系统关键种进行了有益的探讨。为促进我国生态系统保护具有一定的理论指导和现实意义。 相似文献
896.
随着北京地区人口的增多,人类活动范围越来越大,野生维管束植物的分布也逐渐发生了变化.依据北京地区实地野外调查数据及相关文献,对15个调查单元的野生维管束植物进行统计分析.结果表明:北京地区野生维管植物共计1505种,国家重点保护野生维管束植物3种,北京市保护野生维管束植物98种,受危胁野生维管束植物36种,中国特有野生维管束植物199种,且主要分布于门头沟区、密云县、延庆县、怀柔区、海淀区、房山区、昌平区.本文的研究对北京市各县(区)进行生物多样性评价及生物多样性保护等提供了最新最基础的数据. 相似文献
897.
Artur Osikowski Sebastian Hofman Aleksandra Rysiewska Boris Sket Simona Prevorčnik 《Journal of Natural History》2018,52(5-6):323-344
Belgrandiella A. J. Wagner, 1927 is a genus comprising minute snails with conic or turriform shells that are facultative stygobionts, inhabiting subterranean waters and springs. Few specimens or even empty shells of this taxon can be found, so the taxonomy is based mostly on the shell morphology and geographic distribution. Anatomy is known for a few taxa, and its usefulness is restricted. This, coupled with a popular idea that isolation is the first factor shaping divergence and speciation of the spring/cave fauna, resulted in dozens of nominal species of Belgrandiella, known from shells at a given locality. Herein we present shells, anatomy and four molecular markers (nuclear H3, 18S and 28S and mitochondrial cytochrome oxidase subunit I) in Belgrandiella from 16 localities in Slovenia, northern Croatia, and Bosnia and Herzegovina. Five sites are type localities of Boleana umbilicata, Belgrandiella kusceri, Belgrandiella krupensis, Belgrandiella zermanica and Belgrandiella robusta, respectively. Considering the shell and geographic distribution, we have determined B. cf. robusta Belgrandiella cf. croatica, Belgrandiella cf. fontinalis, Belgrandiella cf. kuesteri, Belgrandiella cf. pageti and Belgrandiella cf. koprivnensis The shells of all, as well as penes and female reproductive organs of two putative, species have been illustrated. Molecular analysis indicates four distinct clades, most probably of species rank for B. kusceri, B. cf. kuesteri, B. cf. fontinalis and B. cf. koprivnensis. Four nominal species (B. krupensis, B. robusta, B. umbilicata and B. zermanica) and one genus (Boleana) must be synonymised with Belgrandiella kusceri, and there are no more than four valid, biological species in the studied Belgrandiella. The molecular divergence is completely unmirrored by high morphological variability. Hence the level of endemism is markedly overestimated in these snails. 相似文献
898.
In the present study, the subfamily Cardiochilinae (Hymenoptera: Braconidae) is revised. This study is based on specimens deposited in Egyptian repositories. Many of them were collected during Priesner’s trips to Gebel Elba (extreme south-west of Egypt). The subfamily Cardiochilinae is represented in Egypt by 11 species in three genera, Bohayella Belokobylskij, 1987 (one species), Cardiochiles Nees, 1819 (three species) and Schoenlandella Cameron, 1905 (seven species). The cardiochiline species C. pseudofallax Telenga, 1955 and S. deserta (Telenga, 1955) are recorded here as new records in the fauna of Egypt. The females of previously known male C. weidholzi Fischer, 1958, S. acrenulata (Fischer, 1958) and S. obscuriceps (Fischer, 1958) as well as the male of the previously known female S. glabra (Fischer, 1958) are described. Schoenlandella pseudoglabra sp. nov. is also described and illustrated.
www.zoobank.org/urn:lsid:zoobank.org:pub:C134A1AA-81F6-4661-9C7B-12A7CAE08F67 相似文献
899.
Philippe J. R. Kok Mátyás A. Bittenbinder Joris K. van den Berg Sergio Marques-Souza Pedro M. Sales Nunes Alexandra E. Laking 《Journal of Natural History》2018,52(13-16):1029-1066
ABSTRACTThe gymnophthalmid lizard genus Neusticurus Duméril and Bibron, 1839 currently contains six described species. One of them, Neusticurus rudis Boulenger, 1900 has a long history of taxonomic confusion, and uncertainty remains about the number of species involved under that name, especially in the Pantepui region. Our molecular phylogenetic (concatenation and species tree) and morphological (morphometrics, external and hemipenial morphology) analyses confirm Neusticurus rudis as a species complex with several candidate species in the eastern Pantepui region. Neusticurus rudis is here redescribed based on the re-examination of the holotype and 10 specimens from the vicinity of the type locality (ca. 15 km airline) in Guyana. The geographic distribution of N. rudis sensu stricto is restricted to east of the Venezuelan Gran Sabana, extending from the slopes of Mount Roraima in Venezuela through the slopes of Maringma-tepui and Wayalayeng to Mount Ayanganna in Guyana, between 678 and 1500 m elevation. Populations tentatively assigned to N. rudis also occur from Mount Wokomung in the Pakaraima Mountains of Guyana to the Iwokrama Forest Reserve in Guyana, between 159 and 1234 m elevation. A new Neusticurus species is described from the uplands and highlands of the eastern Pantepui region, west of the Venezuelan Gran Sabana in Brazil and Venezuela, between 900 and 2200 m elevation. Populations provisionally assigned to the new species were also found from the La Escalera region to Chivatón, the summit of Abakapá-tepui and the slopes and summit of Auyán-tepui, Venezuela, between 1100 and 2203 m elevation. Our results suggest the Gran Sabana as a possible recent biogeographical barrier for the genus in the region and indicate that tepui-summit Neusticurus populations derive from uplands populations that shifted their habitat preference.www.zoobank.org/lsid:zoobank.org:pub:33DCF862-11CF-4FD0-B4D6-706E2C6A339E 相似文献
900.
Takafumi Nakano Ko Tomikawa Zhonge Hou Hiroshi Morino 《Journal of Natural History》2018,52(17-18):1181-1199
A new landhopper talitrid, Myanmarorchestia nunomurai Nakano and Morino, sp. nov., from Yunnan Province, China is described. Since species of Myanmarorchestia were known only from Mt. Victoria of the Arakan Mountains of Myanmar, this is the first record of the genus from China. Myanmarorchestia nunomurai is characterised by its coxal gills on gnathopod 2 to pereopod 6 without filamentous projections while the other congeners from Myanmar possess some/all of the coxal gills with filamentous projections. Additionally, M. nunomurai can be diagnosed by the sexually dimorphic uropod 2, of which the outer ramus bears a robust seta on the midlateral surface and a few rows of small teeth on the middle to distodorsal surface.
http://zoobank.org/urn:lsid:zoobank.org:pub:3C014FFC-F4D6-4F18-8188-33672367ABB1 相似文献