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1.
为了解娘娘山国家湿地公园苔藓植物区系特点,对苔藓植物的物种组成和中国特有种的迁移特点进行了研究.结果表明,湿地公园共有苔藓植物51科106属266种(含12变种),易危苔藓植物2种.苔藓植物区系可划分为17种类型,以北温带分布(17.37%)占优势,其次是热带亚洲分布(14.83%).属于热带(73种.R)区系类型的物...  相似文献   

2.
选取北京松山国家级自然保护区开展兰科植物多样性调查和分析,评估其保护现状。松山共有兰科植物12属18种,其中北方盔花兰为北京新记录种。在生活型方面,以地生兰为主,计14种(77.78%),腐生兰4种(22.22%);在分布区类型方面,属的区系成分以北温带分布为主(6属,5000%),兼有旧世界温带分布(3属,25.00%)、世界分布(2属,16.67%)和旧世界热带分布(1属,8.33%);种的区系成分以东亚分布为主(9种,50.00%),兼有旧世界温带分布(5种,27.78%)和北温带分布(4种,22.22%)。松山兰科植物集中分布于北沟和小海坨山。通过综合分析松山兰科植物保护现状,提出生境评估、种群动态监测、建立迁地保护资源圃和加大宣传等都是切实加强兰科植物保护工作的可行措施。  相似文献   

3.
《农业工程》2020,40(3):197-203
This study was conducted to assess the floristic composition, biological spectra and phenology of Tehsil Balakot. Frequent visits were made in different seasons during 2012–13. Field notebook was used to record the data within field. Biological spectrum and leaf sizes classes were determined. The floristic diversity revealed 228 plant species belonged to 184 genera and 72 families. Asteraceae family contributed maximum number of species (27) followed by Rosaceae (18), Apiaceae and Lamiaceae (12) species each, Papilionaceae (11) species while remaining 67 families contributed less than 10 species. Herbaceous growth form was the most leading one (71%), followed by shrub (15%) and tree (14%), respectively. Biological spectrum revealed that hemicryptophytes (32.45%) were the most prevalent, followed by therophytes (31.57%), nanophanerophytes (15.35%), megaphanerophytes (13.59%) and chamaephytes (4.38%). Leaf spectra showed that microphyll (28.94%) were dominant, followed by nanophyll (27.19%), leptophyll (22.80%), mesophyll (14.03%) and megaphyll (7.01%). The flora was influenced by two flowering seasons i.e. March to August and September to February. In the first spell, 193 species were recorded, of these 15.54% trees, 15.02% shrubs, 63.21% herbs, 3.62% grasses and 2.59% ferns; while in the second spell, there were 35 species having 2.85% trees, 17.14% shrubs, 74.28% herbs, and 5.71% grasses. The flowering data shows that June and July were the utmost flowering months with 28.50% in 65 and 20.17% in 46 plant species.  相似文献   

4.
Aim We provide the first in‐depth study of the Branchiopoda of the rain forests of Cameroon and also of the African continent. Location Surface water environments, Cameroon. Methods Qualitative plankton samples were collected in all types of surface water environments present, ranging from big lakes to water collected in rock crevices or fallen fruit cavities. A tow or hand‐held plankton net of mesh size 100 μm was used, and water volumes filtered were at least several m3 in large water bodies, or half to whole water volume in small water bodies. Results We recorded 61 species (53 first records for the country), based on 700+ samples collected between September 1998 and March 2002. Anomopoda (92%) was the dominant order, followed by Ctenopoda (6.5%) and Cyclestherida (1.5%). Chydoridae (67%) was the most speciose family followed by Macrothricidae (6.5%) and Daphniidae (5%). Alona (11%) was the dominant genus followed by Chydorus (10%) and Pleuroxus (8%). Several species of Chydorinae, especially of the genus Pleuroxus, are shared with continental Eurasia–North America, but are absent from the Mediterranean and desert–steppe–savanna zones of Africa (boreal–tropical disjunction). Daphnia was absent, as in most tropical lowlands. No single species was really abundant, and a majority were rare to very rare, and of restricted occurrence within the rain forest patches. Comparing Africa, South America and Southeast Asia, we found a current total of 196 species for the combined rain forest areas, out of a world total of 500+ species. Systematic trends in richness at three taxonomic levels were the same for all continents: Anomopoda–Ctenopoda–Cyclestherida at ordinal level, Chydoridae–Daphniidae–Macrothricidae–Sididae at family level and Alona–Chydorus–Macrothrix–Diaphanosoma at genus level. Southeast Asia was richest (111 species, 14 endemics) with South America a close second (110 species, 27 endemics). Africa was the most species‐poor (95 species, of which only 5 are endemics). Main conclusions We hypothesize that the post‐Miocene cooling and aridization of the world climate hit the freshwater biota of Africa particularly hard, with more extinction here than elsewhere, and little recolonization. Most extinction occurred in the savanna‐desert belt, and eight disjunct boreal species (four Pleuroxus, Picripleuroxus laevis, Kurzia latissima, Alonella exigua, and Monospilus dispar) survive morphologically unchanged since pre‐Pleistocene times in the Cameroon rain forest. Slow evolution thus appears typical of these cyclic parthenogenetic branchiopods in which sexual recombination occurs only at intervals. Illustrative of the same slow evolution is the fact that the two endemic cladocerans of Cameroon (Nicsmirnovius camerounensis and Bryospilus africanus) belong to tropicopolitan genera of Gondwanan age.  相似文献   

5.
《农业工程》2019,39(5):372-379
The Himalayas are one of the youngest and richest ecosystems on earth with a variety of species and forest types due to the varying altitude, topographic, and climatic conditions. The present study was aimed to investigate the floristic composition and biological spectrum of Keran valley, a region nestled in the northwestern frontiers of Himalayan biodiversity hotspot. Floristically, a total of 183 species were recorded, out of which 55 were aliens. Herbaceous growth form was dominant (67%) and therophytes were the dominant (37%) life form. Likewise, mesophylls (34%) followed by nanophylls (29%) and microphylls (27%) were major leaf size categories; and the simple leaf lamina type was recorded in majority of the species (65%). Almost 1/3rd of the total species pool was growing in the forest habitats, while as the 2/3rd occur within the rest 9 habitat types which were largely human-modified. The vegetation phenology observed during different seasons revealed that most of the species were dominant in summer season (37%), followed by spring (29%), autumn (21%) and winter (13%). The present study provides baseline information on the plant diversity in this hitherto unexplored region of northwestern Himalaya.  相似文献   

6.
《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   

7.
Rebecca Hsu  Jan H.D. Wolf 《Flora》2009,204(8):612-627
We present the first checklist of vascular epiphytes in Taiwan, based on herbarium specimens, literature records, and field observations. Epiphyte phytogeography was analyzed using Takhtajan's modified division in floristic regions. We ascertain the presence of 336 species of vascular epiphytes (24 families, 105 genera) in Taiwan. Pteridophytes contribute most species (171 species), followed by orchids (120 species). Epiphytes contribute 8% to Taiwanese floristic diversity and epiphyte endemism is near 21.3%. The extensive mountain system is probably the most effective driver for epiphyte diversification and endemicity in Taiwan. Phytogeographically, Taiwanese epiphytes exhibit equal affinity to the Malesian region, southern China and Indo-China and Eastern Asiatic regions. However, some species have a disjunctive distribution between Taiwan and SW China and/or E Himalaya, presumably related to low habitat similarity with adjacent China and/or the legacy of Late Quaternary climate change. Vascular epiphyte distribution patterns corroborate the phytogeographical separation of the island of Lanyu from the main island of Taiwan along Kanto's Neo-Wallace Line.  相似文献   

8.
Conservation planning in the face of global change is still in its infancy. A suggested approach is to incorporate environmental gradients into conservation planning as they reflect the ecological and evolutionary processes generating and maintaining diversity. Our study provides a framework to identify the dominant environmental gradients determining floristic composition and pattern. Nonmetric multidimensional scaling was used on 2155 sampling plots in savanna and grassland habitat located across the province of KwaZulu‐Natal, South Africa (94 697 km2), a floristically rich region having steep environmental gradients, to determine the dominant gradients. Hierarchical cluster analysis was used to group similar plots which were then used in a Classification and Regression Tree analysis to determine the environmental delimiters of the identified vegetation clusters. Temperature‐related variables were the strongest delimiters of floristic composition across the province, in particular mean annual temperature. Frost duration was the primary variable in the Classification and Regression Tree analysis with important implications for savanna/grassland dynamics. Soil properties (base, pH status) and moisture variables accounted for most of the variation for the second and third axes of floristic variation. Given that climatic and edaphic variables were well correlated with floristic composition, it is anticipated that a changing climate will have a marked influence on floristic composition. We predict warmer temperatures may facilitate the spread of frost sensitive savanna species into previously cooler, grassland areas. Species associated with specific soil types will not easily be able to move up the altitudinal gradient to cooler climes because geology is aligned in an approximately north‐south direction compared with increasing altitude from east‐west. Future conservation planning should take cognisance of these gradients which are surrogates for ecological and evolutionary processes promoting persistence.  相似文献   

9.
This first ever study was carried out to explore the floristic composition of protected and unprotected forests of Sathan Gali, District Mansehra, KP, Pakistan. The study area being the part of the Western Himalayas harbours rich floristic diversity. In the current investigation, an effort was made to record primary data about floral diversity of the area. The study area was visited recurrently during 2013 and 2014. Plants were collected from different sampling sites, identified, preserved and deposited in Herbarium of Hazara University, Mansehra. A total of 127 plants species including 59 common and 68 different were found in 13 stands of reserved forest. The different species were only confined with this forest whereas common plant species were distributed in both forests. The dominant family was Asteraceae (13 species, 10.7%) followed by Labiateae (10 species, 7.75%), Poaceae and Rosaceae (8 species, 6.2%) each, Polygonaceae and Pteridaceae by (5 species, 3.87%) each. Angiosperms were represented by 118 (92.91%), plant species, Pteridophytes 5(3.93%) species and Gymnosperms 4 (3.14%) species were recorded in reserved forest. Only single species of climber was documented. The number of herbs, shrubs and trees species recorded were 73.64%, 13.17% and 10.07% respectively. A total of 103 plant species of 55 families including 61 common in both forest types and 42 species different to guzara Forest. These plant species were recorded from 22 sampling stands. Angiosperms by (92.3%) plant species, Gymnosperms (2.88%) and Pteridophytes (4.8%) were recorded. The dominant family was Poaceae by 11 plant species followed by Asteraceae and Rosaceae each represented by 10 species and Pteridaceae by 5 plant species. Habit wise 69.23% were herbs, 14.42% shrubs and 16.34% species of tree were reported. This study will assist ecologists, botanists, taxonomist, conservationists and policy makers to mend, and manage the current vegetation status and sustainability for upcoming generations. The present investigation will also serves as base line for future researches on the Himalaya regions.  相似文献   

10.
We updated the floristic checklist of the Nizanda region, Isthmus of Tehuantepec (southern Mexico), characterized the occurring plant communities based on dominant species, and described the region’s flora according to life form, growth form, growth type, and growth habit spectra. Ten years of botanical exploration, along with surveys in 188 100-m2 samples from different vegetation types, provided the baseline floristic information. Ordination and classification analyses were performed to examine the degree of differentiation between communities. Geographical ranges of all species were used to assess biogeographical relationships of this flora. The inventory includes 920 species (553 genera, 124 families). More than one-third of the families were represented by a single species, whereas the 10 richest families had 43% of the species richness. Dendrograms showing plot classification at three taxonomic levels (species, genus and family) revealed savannah as the most strongly differentiated community amid seven vegetation types. Regarding growth forms, forbs and trees prevailed. Phanerophytes were the most common life form category, whereas herbs and woody plants were the dominant growth types. The largest richness for all taxonomic levels was recorded in the tropical dry forest. The expanded floristic knowledge gained for the Nizanda region provided better criteria to revise the classification scheme of its vegetation. Our preliminary biogeographical analysis illustrates the role of the Isthmus of Tehuantepec as a corridor for thermophilous floras between two oceanic watersheds, and as a natural distributional limit for several Mesoamerican plant species.  相似文献   

11.
This study investigates the role of climate in determining phytogeographic regions, focusing particularly on the Irano-Turanian floristic region in SW and Central Asia. A set of simple climatic variables and bioclimatic indices were used to prepare climate-space scatter plots and climate diagrams. The climate data were also subjected to multivariate analyses (PCA and Regression tree) in order to develop a bioclimatic characterization of the Irano-Turanian region in comparison with the adjacent Mediterranean, Saharo-Sindian, Euro-Siberian, and Central-Asiatic regions. Phytogeographic regions of SW and Central Asia display distinct bioclimatic spaces with small overlaps. The Irano-Turanian region is differentiated from surrounding regions by continentality, winter temperature, and precipitation seasonality. Continentality is the most important bioclimatic factor in differentiating it from the Mediterranean and Saharo-Sindian regions and is responsible for floristic differences among sub-regions of the Irano-Turanian region. In our case study, the Irano-Turanian region is a nearly independent bioclimatic unit, distinct from its surrounding regions. Hence, it is suggested that the term “Irano-Turanian bioclimate” be used to describe the climate of most of the continental Middle East and Central Asia. Among different sub-regions, the west-central part of this floristic region (“IT2 sub-region”) is a major center of speciation and endemism. Our case study demonstrates that climate is a primary determinant of phytogeographic regionalization. Although modern climate and topography are strong control parameters on the floristic composition and geographical delimitation of the Irano-Turanian region, the complex paleogeographic and paleoclimatic history of SW Asia has also influenced the Tertiary and Quaternary evolution of the Irano-Turanian flora, with additional impacts by the long-lasting historic and present land-use in this region. Many Irano-Turanian montane species are threatened by global warming, and particular conservation measures are needed to protect the Irano-Turanian flora in all sub-regions.  相似文献   

12.
Traditional cultural and religious beliefs and practices in the form of sacred groves play a crucial role in environmental conservation and biodiversity. The present study was conducted to explore plant resources, their biological spectrum, leaf size spectrum, sacred grove conservation status, locally known as Kankabati Sitabala Than (KST) in the district of West Midnapore, West Bengal in India. The study's floristic list revealed that the KST vegetation was diverse and composed of 277 species of 238 genera distributed over 77 families under 36 orders according to APG IV classification, of which 87 species were aliens. Poales (23.40%) and Poaceae (15.38%) were the dominant order and family in terms of species wealth. Biological spectrum shows the study area was classified as “thero-crypto-chamaephytic” type of phytoclimate. Leptophyll (26.60%) and ovate (18.91%) were found to be high in the leaf size spectrum and lamina. The vulnerable climber and tree species are Cayratia pedata and Pterocarpus indicus. The vegetation phenology, observed during different seasons revealed that most of the species were dominant in rainy seasons (99.68%), followed by winter (69.87%) and summer (29.81%). The study area being a sacred grove remains fairly undisturbed. For the long-term conservation of germplasm of the grove some recommendations have been suggested.  相似文献   

13.
The aim of this study is to compare the recovery dynamics in three shrub communities subjected to experimental burning and cutting, and situated on an altitudinal gradient. Climatic features are different in each area, but all had the common characteristic of very homogeneous vegetation cover before the disturbances, with only one shrub species clearly dominant, a different taxon in each area, and with different regeneration strategies. The first area was a heathland dominated by Calluna vulgaris, situated at an altitude of 1600 m, with a continental climate (mean annual precipitation 1320 mm). The second area was a heathland dominated by Erica australis, located at an altitude of 1000 m (mean annual precipitation 840 mm). The third area was a Cistus ladanifer shrubland, located at 900 m altitude, with a Mediterranean climate similar to that of the previous area, but with lower mean annual precipitation (470 mm). Erica australis recovers by vegetative resprouting, but Cistus ladanifer is an obligate seeder, as is Calluna vulgaris in these areas. Each experimental disturbance was carried out over 100 m2 in each area. Post-fire recovery is faster in Cistus ladanifer: 2 years after burning there was 40% cover vs. less than 20% in the other two species. However, recovery after cutting was similar for Cistus ladanifer and Erica australis. Calluna vulgaris recovers very slowly, with cover values below 20% even 10 years after both disturbances. Cover of dominant shrub species is negatively correlated with cover of herbaceous species. So different recovery of dominant species lead a different community dynamic in each area.  相似文献   

14.
《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   

15.
Recent investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified some fossiliferous beds in the Lower Gondwana deposits. Two exposures of the Lower Kamthi Formation yielded diverse and abundant plant remains, which includeNeomariopteris, Vertebraria, and a scale leaf along with 14Glossopteris species otherwise mapped as Barren Measures and Upper Kamthi formations.Glossopteris indica dominates the flora (22.78%) followed byG. communis (17.72%) andG. browniana (13.92%). Based on megafloral assemblages, different beds exposed at Gopalpur and Laxamanpur Pahar are assigned here to the Lower Kamthi Formation (Late Permian). The floristic composition suggests that a warm and humid climate prevailed during the Late Permian. The status of the Kamthi Formation in the Ib River Coalfield has been redefined in the present study.  相似文献   

16.
Aim This study was conducted to investigate the potential of predicting alpha diversity and turnover rates of a highly diverse herbivorous insect family (Geometridae) based on vascular plant species richness and vegetation structure. Location The study was carried out on the south‐western slopes of Mount Kilimanjaro within a wide range of habitats between 1200 and 3150 m elevation. Methods The floristic and structural composition of the vegetation was recorded at 48 plots of 400 m2. Geometrid moths were sampled manually at light sources located at the plot centres. Principal components analysis, redundancy analysis and multiple linear regression were used to explore how alpha diversity and species turnover of geometrid moths are related to vegetation structure and plant species richness. Results Alpha diversity of geometrid moths was significantly correlated with species diversity patterns in the most common vascular plant families (R2 = 0.49) and with plant structural parameters (R2 = 0.22), but not with overall floristic diversity. Species turnover of geometrid moths was strongly linked to diversity changes in a range of plant families (40% explained variance), less strongly to changes in vegetation physiognomy (25%), and only weakly to overall floristic diversity (5%). Changes in elevation were a better predictor of both alpha diversity and species turnover of geometrid moths than any principal component extracted from the vegetation data. Main conclusions Vegetation composition, diversity and structure all showed significant correlations with the diversity and species composition of geometrid moth assemblages. Nevertheless, in most cases relationships were indirect, via environmental parameters such as temperature and humidity, which influenced both vegetation and moth fauna. Possible direct links between geometrid diversity and potential food plants were much weaker. The lack of a significant correlation between overall plant species richness and geometrid diversity indicates that tropical geometrid moths may not be very selective in their food plant choice. Accordingly, a clear correlation between floral diversity and herbivore species richness must be regarded as overly simplistic, and the diversity of vascular plants cannot universally be used as a suitable biodiversity indicator for diverse insect taxa at higher trophic levels.  相似文献   

17.
The current study intends to evaluate the many hazards affecting the spread of the significant fodder grass Lygeum spartum Loefl. ex. L. and its associated species in Egypt's Western Mediterranean Desert over the past 60 years (from 1958 to 2020); depending on the data of the previous literature and the current situation evaluation by recent field trips. It also aims to assess its ecosystem services. Sixty-nine stands were collected from previous studies and unpublished data, in addition to 30 stands (10 m2) were added including 5 field trips during the period from spring 2019 to spring 2020. Measurements were taken to create a classification of this vegetation and to determine the main threats that affect its distribution composition. There are 142 species associated with the distribution of the studied plant in 6 habitats. While only 107 species were recorded in the recent stands in 7 habitats. Vegetation groups (G1- G8) obtained from TWINSPAN classification indicating that G1 (wadis) is the most diverse group with a species richness 34.7 species per stand, while G6 (dune) has the highest species turnover (4.57) during the period of 1958 to 2014. But in recent stands; G5 (saline and non-saline depression) is the most diverse group (30.875), while G2 (dunes) has the highest species turnover (4.819). Medicinal plants are the most represented (79.86%), followed by grazing plants (72.9%). The most common service is sand stabilization (92% of total services), followed by windbreak (natural) (40%). Threatened species represent 92.4%; habitat loss is the most affected threat (95 species), followed by over-collecting and over-cutting (82 species). Twenty out of 99 stands (20.2% of the total stands) have been destroyed due to human activity. Continuous monitoring of remaining patches of Egypt’s northwestern Mediterranean coast was required to save its natural flora from extinction.  相似文献   

18.
[目的] 完善江西省外来植物本底调查数据,为江西省外来入侵植物的预防和预警机制构建提供依据。[方法] 通过文献、标本研究以及野外实地调查,对江西外来植物种类、原产地、生活型、引入途径、引入时间、在各地级市的分布情况以及外来入侵植物的种类进行分析、探讨。[结果] 江西省外来植物有106科407属599种:菊科最多(85种,14.19%),其次是豆科(52种,8.68%),10种以下的科有91个,占总科的85.85%;主要源于美洲(49.25%),其次是亚洲(20.80%),欧洲第三(13.81%),地中海和大洋洲较少;外来植物中草本植物种类最多,乔木次之;大部分被用于观赏、饲料、药物等有意引入。江西省的外来入侵植物有53科168属267种;九江、赣州和南昌由于地理位置优越及经济地位突出被入侵较严重。[结论] 江西省外来植物种类丰富,引入途径多样,入侵物种较多。建议构建风险评价系统,加强外来植物监管监测,科学引种;制订和更新外来植物防控的具体政策法规;同时,加大入侵危害宣传,及时防控和阻止外来植物逃逸入侵对本省生态环境造成侵害。  相似文献   

19.
《Journal of Asia》2007,10(2):177-180
Study on the species diversity of the order Odonata was carried out during 2002 ∼ 2004 at Dholbaha dam, which has a moist deciduous forest surrounding it in district Hoshiarpur, Punjab, India. A total of 30 species belonging to 7 families of order Odonata were recorded during the study period. The family Libellulidae, represented by 18 species was the most dominant followed by Coenagrionidae (6 species), Aeshnidae (2 species) and Calopterygidae, Chlorocyphidae, Euphaeidae and Gomphidae each having 1 species. In terms of total number of individuals, family Libellulidae constituted maximum with 64.36% followed by Coenagrionidae (28.50%), Chlorocyphidae (1.83%), Gomphidae (1.62%), Euphaeidae (1.56%), Calopterygidae (1.38%) and Aeshnidae (0.75%). Pantala flavescens (Fabricius), a migratory species was the most dominant in number of individuals constituting 17.12% of the total. The least dominant species included Anax immaculifrons Rambur (0.38%) and Anax parthenope parthenope (Selys) (0.36%). Shannon-Wiener index of species diversity of Odonata was 2.988 and 3.029 during 2002–2003 and 2003–2004, respectively. Seven new species have also been reported from the Dholbaha dam during this study period thus increasing the total species number of odonates so far recorded from this area from 29 to 36.  相似文献   

20.
The soft-bottom caprellids of the Iberian Peninsula are revised. Nineteen species have been reported so far, 42 % being endemic to the Mediterranean Sea. The lateral view of all of them is provided, together with an illustrated key for all the species. An ecological study was also conducted during 2007–2010 along the Andalusian coast to explore the relationships of caprellids with abiotic data. A total of 90 stations (0–40 m deep) were sampled and 40 contained caprellids. Along the Atlantic, caprellids were present in only 20 % of the stations, while along the Mediterranean coast, caprellids were present in the 75 % of the sampling sites. Furthermore, the abundance of caprellids was also higher in the Mediterranean coast. The dominant species was Pseudolirius kroyeri (present in 24 stations and showing the highest abundances with 1,780 ind/m2), followed by Phtisica marina (22 stations) and Pariambus typicus (11 stations). According to CCA and BIO-ENV, sediment type, P, pH and oxygen were the parameters that better explained the distribution of caprellids. Although the three dominant species were found in all types of sediment, the univariate approach showed that P. kroyeri was significantly more abundant in fine sediments (silt–clay and very fine sands) than in gross sediments (coarse and very coarse sands). The majority of studies dealing with caprellids from the Iberian Peninsula have been focused on shallow waters and further efforts are needed to explore biodiversity of deeper areas.  相似文献   

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