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1.
This study reviews the trends in the lifestyle, habitat distribution and trophic diversity of the 2377 described species of dinoflagellates (Dinophyceae). Most of the dinoflagellates inhabit marine waters, whereas 17% of the total species have colonized continental waters. Dinoflagellates are dominated by planktonic species, while benthic forms represented 8% of the species. From the total number of species, 49% are heterotrophic (devoid of plastids), while 51% of the species have been reported with plastids (that does not strictly imply autotrophy). All the basal dinoflagellates (ellobiopsids, Duboscquodinida, Syndiniales) are heterotrophic, with the exception of a few Noctilucales (Spatulodinium). The continental waters are highly dominated by plastid-containing species (88%), while in marine environments there is a slight dominance of heterotrophic species (58%). Most of the dinoflagellates are free-living forms; only 7% of the total species are parasites. The dinokaryotic parasites appear in separate clades, and about 40% of them contain plastids. The beneficial or mutualistic symbionts (21 species, 1%) are photosynthetic species dispersed into at least three clades.  相似文献   

2.
《农业工程》2021,41(6):524-536
This study was conducted during 2018–19 to evaluate the floristic composition and ecological characteristics of vegetation of Pashat valley, Bajaur. Floristic list of the valley contains 385 species distributed in 291 genera and 102 families. The dicotyledons having 83 families with 311 species and monocotyledons with 12 families contains 61 species. Pteridophytes having 05 families with 11 species and gymnosperm with a single family of two species. The leading family was Asteraceae with 42 species (10.90%) followed by Poaceae with 39 species (10.10%), Papilionaceae (Fabaceae) with 24 species (6.23%), Lamiaceae with 20 species (5. 19%) and Rosaceae with 15 species (3.90%). Therophytes 180 species (46.80%), hemicryptophytes 53 species (13.80%), nanophanerophytes 51 species (13.20%) and geophytes 35 species (9.09%) were the dominant life form groups. Leaf size class was dominated by microphylls (138 species, 35.84%) followed by nanophylls (124 species, 32.21%) and mesophylls (89 species, 23.12%). Habit wise the vegetation was mostly herbs (289 species) followed by shrubs (54 species), trees (38 species) and lianas (4 species). According to flowering phenology, most plants (62.30%) bloomed in spring followed by in summer (34%), in autumn (1.82%), in the whole year (1.30%) and in winter (0.52%). Based on chorological affinities, most of the species were bioregional in distribution (170 species, 44.15%) followed by mono-regional (157 species, 40.78%), pluri-regional (43 species, 11.17%) and cosmopolitan (15 species, 3.89%). The ecological characteristics like life form and leaf size spectra of the vegetation have a strong correlation with the prevailing environmental conditions such as altitude, slope, precipitation and temperature.  相似文献   

3.
Floristic inventory of village Sherpao, District Charsadda comprised of total 104 plant species belonging to 46 families and 95 genera. The leading families included Fabaceae, Asteraceae, Poaceae and contributed by 8 species one (7.69%).The most pre-dominant life form was therophytes having 35 species (33.65%). Most dominant habit of flora were herbs having 77 species (74%) followed by trees contributed by 18 species (17.30%) and shrubs having 9 species (8.65%). Leaf size spectra of the flora showed that the most dominant leaf size class were microphyll having 38 species (36.53%) followed by nanophyll contributed by 32 species (30.76%), mesophyll represented 22 species (21.15%) and leptophyll contributed by 12 species (11.53%). Based on habitat 77 species (74%) were xerophytic in nature followed by 14 species (13.46%) in wet condition and 13 species (12.5%) were present in both conditions. In 104 plant species 85 were non spiny and 19 were spiny. Plant growth and distribution are having strong correlation with environment. Therefore, it is important to understand the environmental aspects that affect plant growth and distribution.  相似文献   

4.
In this study, we survey the plant diversity of Wadi Hassan, which is located in the Northeastern Badia of Jordan, about 120 km east of Amman. All plant species were collected and herbarium specimens have been prepared, identified and deposited at the University of Jordan herbarium(Department of Biology,Faculty of Science). The final plant checklist includes 206 species belonging to 138 genera and 35 families.The most diverse families are Compositae(20.5%), Cruciferae(10.2%), Leguminosae(8.3%) and Boraginaceae(6.8%), followed by Caryophyllaceae and Gramineae(5.4%). These six families represent 60% of the total families recognized in the study area, while nine families each are represented by only one species. Most plants recorded are annual plants(61%), some plants are hemicryptophtes(18%) and camaephytes(15%), while the least frequent life form class was the phanerophyte shrub and perennial(0.5%). Chorological characteristics of the recorded flora show that Saharo-Arabian Region elements, IranoTuranian elements and Mediterranean elements constitute(58%) of the total flora. This research shows that even small portion of the Jordan Badia such as the Wadi Hassan plant community has high species diversity. Thus, we recommended further of the unexplored Wadi plants communities of the Jordan Badia.  相似文献   

5.
《农业工程》2020,40(3):221-236
The floristic study carried out during 2015–2018 revealed that the flora of Koh-e-Safaid Range comprised of 654 species, 401 genera from 116 families. Leading families were Poaceae 72 species (11.07%), Asteraceae 56 species (8.61%), Rosaceae 43 species (6.61%), Lamiaceae 41 species (6.25%), Papilionaceae 38 species (5.84%), Brassicaceae 32 species (4.92%), Ranunculaceae 17 species (2.61%), Apiaceae and Polygonaceae each with 16 species (2.41%). The largest genera were: Prunus (9 species), Potentilla and Astragalus (8 species each), Artemisia, Allium (7 species) Euphorbia and Amaranthus (6 species each), Lepidium, Nepeta and Cotoneaster (5 species each). Therophytes with 257 species (39.23%) were the dominant life form, followed by nanophanerophytes 104 species (15.92%), geophytes 100 species (15.31%), hemicryptophytes 98 species (15.00%). Cuscuta reflexa, Viscum album and Viscum articulatum were three of the shoot parasites. The leaf spectrum was dominated by nanophylls 246 species (37.67%) followed by microphylls 140 species (21.43%) and mesophylls 128 species (19.54%). Eleven species (1.68%) were aphyllous. Majority of the species (459 species, 70.29%) had simple lamina while seven species (1.07%) had spiny leaves. Present report also listed the some of the endemic species while Cleome amblycarpa and Salvia reflexa are reported as a new addition to the list of Flora of Pakistan.  相似文献   

6.
汪书丽  罗建 《西北植物学报》2018,38(8):1534-1541
为了摸清色季拉山蕨类植物资源的种类和资源特征,为该区蕨类开发利用提供依据。该研究通过查阅《西藏植物志》和标本,结合色季拉山多年植物调查名录,对该区野生蕨类植物进行统计分析,并对其用途进行了描述。结果显示:(1)色季拉山共有蕨类植物资源29科、57属、196种(包括变种和变型),分别占西藏蕨类植物总科、属、种的65.91%、45.24%、41.70%;优势科为鳞毛蕨科(3属/50种)、水龙骨科(9属/31种)、蹄盖蕨科(7属/22种)、中国蕨科(6属/14种),优势属为鳞毛蕨属(27种)、耳蕨属(19种)。(2)色季拉山蕨类植物的地理成分以热带类型的科和属占优势(分别占非世界分布科、属的80.00%、68.18%),具有明显的热带性质;生态分布类型以陆生为主(118种,占60.20%),其次为附生(45种,占22.96%)。(3)色季拉山共有药用蕨类植物66种,且以清热药种类最多(30种);观赏蕨类植物共有71种(其中新增加23种);食用蕨类植物共有14种,且多以嫩叶或嫩茎或根状茎为食;少数蕨类还具有指示、工业原料、饲料和绿肥等方面的作用。研究表明,色季拉山蕨类植物资源种类丰富,在西藏蕨类植物区系中占很大比例,具有很高的开发利用价值。  相似文献   

7.
生物多样性的编目和分类以及生物多样性监测是全球生物多样性研究的两个核心内容。物种编目是了解物种多样性的基础, 只有掌握物种分布格局及物种与环境的关系, 才能为物种监测和科学管理提供依据。作为浙江种子植物研究的“家底”, 本文在《浙江植物志(新编)》编研的基础上, 系统整理了浙江种子植物的物种名录。结果显示, 浙江共有种子植物212科1,469属4,430种, 其中野生植物有190科1,085属3,347种。所含种数多于100种的科有禾本科(285种)、莎草科(216种)、菊科(186种)、蔷薇科(153种)、兰科(126种)、蝶形花科(109种)和唇形科(108种); 含20种以上的属有15属, 包括薹草属(Carex, 126种)、刚竹属(Phyllostachys, 44种)、悬钩子属(Rubus, 44种)、冬青属(Ilex, 35种)、蓼属(Polygonum, 34种)、珍珠菜属(Lysimachia, 32种)、铁线莲属(Clematis, 31种)、景天属(Sedum, 28种)、槭属(Acer, 26种)、荚蒾属(Viburnum, 26种)、飘拂草属(Fimbristylis, 26种)、蒿属(Artemisia, 25种)、堇菜属(Viola, 22种)、葡萄属(Vitis, 21种)和山矾属(Symplocos, 21种)。其区系特点主要反映在: 物种丰富, 其科属组成多样; 保存了较多古老孑遗植物; 地理成分多样, 联系广泛, 由热带向温带过渡; 中国特有科2科、中国特有属45属、浙江(准)特有种近500种(含亚种和变种), 珍稀濒危植物丰富, 96种为国家重点保护植物; 外来植物多, 入侵风险大, 有些种已形成明显的危害。  相似文献   

8.
The freshwater crabs of the Neotropics comprise 311 species in two families (Pseudothelphusidae and Trichodactylidae) and one or both of these families are found in all of the countries in the Neotropical region (except for Chile and some of the Caribbean islands). Colombia (102 species, 81% endemic) and Mexico (67 species, 95% endemic) are the biodiversity hotspots of freshwater crab species richness and country-level endemism for this region. The results of the IUCN Red List conservation assessments show that 34% of pseudothelphusids and 10% of trichodactylids have an elevated risk of extinction, 29% of pseudothelphusids and 75% of trichodactylids are not at-risk (Least Concern), and although none are actually extinct, 56% of pseudothelphusids and 17% of trichodactylids are too poorly known to assess (Data Deficient). Colombia (14 species), Venezuela (7 species), Mexico (6 species), and Ecuador (5 species) are the countries with the highest number of threatened species of Neotropical freshwater crabs. The majority of threatened species are restricted-range semiterrestrial endemics living in habitats subjected to deforestation, alteration of drainage patterns, and pollution. This underlines the need to prioritize and develop conservation measures before species decline to levels from which they cannot recover. These results represent a baseline that can be used to design strategies to save threatened Neotropical species of freshwater crabs.  相似文献   

9.
Phytoplankton species collected from the limnetic to euryhaline sections of Tehuantepec River were identified, classified and compared with regional information from Mexico and South America. We collected 15 samples every three months from July 1997 through August 1998 with a 20 microm net and a Van Dorn bottle. Indicator values and a code checklist are included. A total of 58 families, 121 genera, 273 species, one subspecies, 75 varieties, 13 forms and one morphotype were identified in the taxa Bacillariophyta (42.0 %), Chlorophyta (29.0 %), Cyanoprocaryota (18.0 %), Euglenophyta (5.0 %), Dinophyta (3.0 %), Cryptophyta (2.0 %) and Chrysophyta (1.0 %). The predominant families were Scenedesmaceae (24 species), Oocystaceae (22), Bacillariophyceae (21), Chaetocerotaceae (15) and Euglenaceae (14). Five families, eight genera, 72 species, 45 varieties and eight forms are first records for Mexico. The species Chroococcus turgidus, Microcystis flosaquae and Pseudanabaena limnetica (which produce massive blooms or red tides) are important in this river of moderate water quality.  相似文献   

10.
Staines CL 《ZooKeys》2011,(157):45-65
Survey work from 1992-2001 identified 139 species of hispines at the lowland part of La Selva Biological Station, Costa Rica. The tribe Cephaloleiini was the most speciose with 58 species (41.7%) followed by the Chalepini with 55 (39.5%). The fauna is most closely related to that in South America but with some genera which are more speciose in the Nearctic Region. Plant associations are known for 88 (63.3%) of the species but many of these are merely collecting records, not host plant associations. The first plant associations are reported for Alurnus ornatus, Alurnus salvini, and Acentroptera nevermanni.  相似文献   

11.
Seven helminth species were obtained from 12 wild boars (Sus scrofa) during a survey from 2000 to 2001 in Luristan province, western Iran. These species include the cestode larvae Cysticercus tenuicollis (25%), C. cellulosae (8.3%), the nematodes Metastrongylus apri (41.6%), M. pudendotectus (16.6%), M. salmi (8.3%), Trichuris suis (8.3%) and the acanthocephalan Macracanthorhynchus hirudinaceus (41.6%). No trematodes were found. Seven wild boars (58.3%) were identified as having at least one helminth species. A single infection was detected in 16.6% of cases, but a three species infection covered the highest rank (25%). All these helminths have been reported from other areas of Iran including the north, northeast and southwest, but not in Luristan. Among seven helminths identified, at least three species are transmissible to humans. The public health significance of these helminths is discussed.  相似文献   

12.
The hoverfly fauna of the northwestern Caucasus comprises 257 species of 72 genera. They possess 32 types of ranges that could be united into 11 groups of ranges. Widespread species from the basis of the hoverfly fauna in the region: species with narrower ranges, those distributed in more than one zoogeographical region, and those distributed in more than one dominion, constitute 12.9%, 63.1%, and 24% of the fauna, respectively. The hoverfly fauna of the northwestern Caucasus is composed of nemoral species common for Europe and Mediterranean basin, and also by species widespread in the Palaearctic (92.9%). Autochthomous species constitute 5.5%, and species of the eastern Palaearctic origin, 1.6%. Hoverfly species with zoophagous larvae are the most widespread. The fraction of such species is low among species with narrowly local ranges (12.5%) and high among species with ranges including more than one dominion. Phytophagous species are wider represented among hoverflies with narrowly local ranges (44.7%) than among flies with interdominion ranges (8%). Ranges of dendrobiontic saprophagous species are determined by the presence of arboreal vegetation and no widespread polytopic hoverflies are found in this group. The distribution of mycetophagous species, commensals, and terrestrial saprophagous species is determined by the presence of fungi, ranges of some hymenopterans, and the presence of decaying plant remnants.  相似文献   

13.
生物多样性编目与监测是我国各级自然保护区的基础工作。本研究收集整理了四川王朗国家级自然保护区2004-2019年基于实地调查与观测的鸟类记录,数据来源包括公众科学活动、红外相机调查和自动录音记录。共记录鸟类16目55科271种,其中,东洋界物种147种(54.24%),古北界物种94种(34.69%),广布种30种(11.07%);留鸟165种(60.89%),冬候鸟14种(5.17%),夏候鸟67种(24.72%),旅鸟22种(8.12%),迷鸟3种(1.11%);国家Ⅰ级重点保护野生动物5种:鸡形目Galliformes雉科Phasianidae斑尾榛鸡Tetrastes sewerzowi、红喉雉鹑Tetraophasis obscurus、绿尾虹雉Lophophorus lhuysii和鹰形目Accipitriformes鹰科Accipitridae胡兀鹫Gypaetus barbatus、金雕Aquila chrysaetos;国家Ⅱ级重点保护野生动物23种;列入世界自然保护联盟红色名录的10种,列入中国脊椎动物红色名录的34种。结果表明,保护区鸟类区系组成总体上具有南北混杂的过渡特征,兼具东洋界与古北界成分,物种多样性丰富,记录鸟种数占四川省有记录鸟种总数(708种)的38.28%,在鸟类多样性保护中有重要价值。本研究为保护区管理以及未来的鸟类监测和研究提供了基础资料。  相似文献   

14.
Namibia's extant mammal fauna of 250 species represents about 75% of the southern African region's species richness, 83% of generic richness and 98% of familial richness. Fourteen species are presently recognized as endemic (75% or more of the global population occurring within Namibian borders). These endemics occur in the Namib Desert, pro-Namib transition zone and adjoining escarpment, and are primarily rupicolous. The Namibian endemic mammal fauna is characterized by the monotypic Petromuridae, and the rodent genera Gerbillurus and Petromyscus. The distribution of smaller species has probably not changed significantly over the past 200 years, but species such as lion and plain zebra have undergone range reductions of 95% or more, and five species are listed as recently extinct. Approximately 50% of all Namibian mammal species are provisionally listed as 'secure'. However, due to patchy data, 94 species (38%) are classified as under possible or probable threat. Nineteen species (8%) are classified as under definite threat. Over 13% of Namibia is set aside by the state for conservation purposes. Ninety-five percent of mammal species occur in at least one park, over 80% occur in three or more parks, and 59 species (28%) occur in ten or more parks, although for most species nothing is known of their population viability there. Major threats to mammals in Namibia are invasive aliens, including the risk of genetic pollution, and habitat alteration, especially wetland degradation.  相似文献   

15.
西双版纳尚勇亚洲象的食物组成与取食生态   总被引:2,自引:0,他引:2  
陈进  邓晓保  张玲  白智林 《生态学报》2006,26(2):309-316
于1998—2000在西双版纳国家级自然保护区尚勇子保护区的自然生境中,通过对亚洲象取食植物调查和粪便分析,了解亚洲象的食物组成与取食习性。结果显示,野外跟踪调查共记录有106种植物被亚洲象所取食。其中有83种出现在象的粪便中,这些种类分别属于:禾本科8种(10.0%)、桑科7种(9.9%)、蝶形花科4种(8.4%)、五加科3种(6.6%)、葡萄科3种(5.7%)、夹竹桃科3种(4.6%)、芭蕉科1种(4.2%)、姜科3种(3.7%)、紫金牛科3种(3.6%)、蔷薇科3种(3.6%)、大戟科5种(3.3%)、榆科2种(3.O%)、含羞草科4种(2.9%)13个植物科。根据食物中所占的比率,桑科的榕属(Ficus)、禾本科的竹类(Bambusoideae)、小果野芭蕉(Musa acuminate)和莠竹(Microstegium ciliatum)是亚洲象的主要食物资源。在觅食过程中,亚洲象取食包括乔木、藤本灌木和草本等各种生活型的植物,其中先锋种所占比率(59%)高于后续种;选择性啃食枝条的植物种类(77种)高于牧草式取食的种类(6种)。亚洲象取食植物种类的月变化与月平均温度和月降雨量成负相关,旱季取食植物种类高于雨季。本研究对制定保护区野生动物管理策略,以及解决保护区周边日趋恶化的人象矛盾,具有一定的参考价值。  相似文献   

16.
本研究于2017至2019年对广东石门台国家级自然保护区的翼手目动物资源进行调查,调查方法主要为日栖息地与夜栖息地调查、网捕调查,共调查到翼手目动物4科9属31种.其中,菊头蝠科1属7种,占比22.6%,蹄蝠科1属4种,占比12.9%,假吸血蝠科1属1种,占比3.2%,蝙蝠科6属19种,占比61.3%.31种蝙蝠的区系...  相似文献   

17.
Twenty-six species of gastropods (terrestrial, shell-bearing snails and slugs) were recorded at the 'Evolution Canyon' microsite, lower Nahal Oren, Mount Carmel, Israel. Twenty-five species were recorded at the temperate, mesic north-facing slope (NFS) and 20 species at the xeric south-facing slope (SFS). Out of these species, six were NFS specific ( Pilorcula raymondi hebraica , Euchondrus septemdentatus , Monacha crispulata , Pyramidula rupestris hierosolymitana , Truncatellina haasi , and Vitrea contracta ) and one was SFS specific ( Prolimax eustrictus ). The interslope difference was probably partly due to missing forest species at the SFS in comparison with the NFS. Twenty-two species were Levantine endemics (84.6%) and four species were more widely distributed in the Palaearctic region (15.4%). The Levantine species are inhabitants of the mesic and mainly mountainous regions, but four species ( Granopupa granum , Calaxis hierosolymarum , Cecilioides acicula , and Helix engaddensis ) also penetrate the deserts. Seven species ( Buliminus labrosus , H. engaddensis , Levantina spiriplana caesareana , Metafruticicola fourousi , Monacha syriaca , Sphincterochila cariosa , and Xeropicta vestalis joppensis ) were significantly more abundant on the SFS than on the NFS. The local physical microclimatic sharp divergence leads to gastropod adaptive interslope biotic divergence caused by natural selection.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 147–155.  相似文献   

18.
Eighty-one herbal drug species in 51 families and 77 genera are documented. These plants are represented by 3 families of pteridophytes (3.8%), 3 families of Monocotyledons (4.9%) and 45 families of Dicotyledons (91.3%). The medicinal value of 30 species (37%) has not been previously reported from other parts of Nepal. The preparation, utilization and Nepali names along with the scientific names and their role in local culture for healthcare are discussed.  相似文献   

19.
The Asteraceae family has been broadly studied, but the values of genome size of only 3.5% of their species are known. To expand these data, we carried out a flow cytometric study of nuclear DNA content in a wide range of taxa of this family, filling gaps in some less studied groups. In addition, some chromosome counts have been performed (46 taxa, including the first one in two species and one subspecies). We provide genome size data for 167 taxa (184 accessions). Of these, data are new for 128 species and subspecies (141 accessions), 40 genera, three tribes (Barnadesieae, Gochnatieae and Nassauvieae) and two subfamilies (Barnadesioideae and Gochnatioideae). Most values (about 75%) are small or very small (1C ≤ 3.5 pg). The second reports on 17 species previously studied with other methods (i.e. first flow cytometric assessments) are also given. Finally, we contribute results for 22 species for which a first flow cytometric assessment has been published during the preparation of this article. The current data-set moves the percentage of coverage approximately from 3% to 4.7% at the specific level, from 6% to 11.6% at the generic level, from 34.9% to 41.9% at the tribal level and from 33% to 50% at the subfamily level.  相似文献   

20.
T Kumazaki  H Hori  S Osawa  N Ishii    K Suzuki 《Nucleic acids research》1982,10(21):7001-7004
The nucleotide sequences of 5S rRNAs from a rotifer, Brachionus plicatilis, and two nematodes, Rhabditis tokai and Caenorhabditis elegans have been determined. The rotifer has two 5S rRNA species that are composed of 120 and 121 nucleotides, respectively. The sequences of these two 5S rRNAs are the same except that the latter has an additional base at its 3'-terminus. The 5S rRNAs from the two nematode species are both 119 nucleotides long. The sequence similarity percents are 79% (Brachionus/Rhabditis), 80% (Brachionus/Caenorhabditis), and 95% (Rhabditis/Caenorhabditis) among these three species. Brachionus revealed the highest similarity to Lingula (89%), but not to the nematodes (79%).  相似文献   

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