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Seasonal Abundance and Diversity of Birds of Prey and Owls in Al Wathba Wetland Reserve in Abu Dhabi, UAE
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作者 Shakeel Ahmed Salim Jáved +3 位作者 Shahid B. Khan Eissa Al Hammadi Abdullah Al Hammadi Nouf Sameer Alqadi 《Open Journal of Ecology》 2024年第3期228-244,共17页
Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 20... Inland wetlands in Abu Dhabi Emirate are wintering and stopover sites for migratory birds of prey. We conducted long-term regular monitoring surveys in Al Wathba Wetland Reserve (AWWR) from January 1995 to December 2022. Both diurnal and occasionally nocturnal surveys were undertaken to record the migratory raptors and owls in the Wetland Reserve. During the study, a total of 1282 regular monitoring visits were undertaken and 27 species of diurnal raptors and owls representing five families and three orders were detected. These represent 57% of the total species of birds of prey recorded in the UAE. Overall, 63% of all the species that we observed were Accipitriformes followed by 26% Falconiformes and 11% Strigiformes. We found that changes in mean daily temperature have a positive effect on raptor species diversity and abundance in the Wetland Reserve. The species encounter rate was higher in low temperature as compared to high temperature and overall regression equation was statistically significant F (4, 1126) = 8.49), p = 0.00). However, the numbers of raptors did not vary significantly across the years (p = 0.51). Western Marsh-harrier (Circus aeruginosus) and Greater Spotted Eagle (Clanga clanga) were recorded to be the most abundant species in the wetland reserve followed by Common Kestrel (Falco tinnunculus). However, the encounter rate of globally threatened Greater Spotted Eagle was detected to have significantly decreased since 2016. Moreover, 63% of the species detected were uncommon and rarely recorded such as 1) Saker Falcon 2) Lanner Falcon 3) Long-eared Owl & Merlin, which were the rare records from the wetland reserve. Furthermore, 27 years of regular monitoring in the wetland have yielded diverse diurnal raptors and owl fauna (H) = 0.83, (E) = 1.43 (Shannon Diversity Index). The results demonstrate that long-term monitoring surveys in arid environments are essential to determine the trends in the raptor populations and to document rare and globally important species. 展开更多
关键词 Wetland Reserve RAPTORS abundance diversity Abu Dhabi Inland Wetland AWWR Greater Spotted Eagle
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Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan
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作者 Abdallah Gordon Shazali Joseph Mayindo Mayele +1 位作者 Joel Emmanuel Saburi Jubara Nadlin 《Open Journal of Ecology》 2024年第5期483-507,共25页
Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habi... Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the Kruskal Wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-Weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human footprints and tree cutting combined accounted for 9%, indicating the practice of livestock grazing, poaching, encroachment, and fuelwood collection by local communities. However, these activities did not appear to significantly impact the diversity, abundance, and distribution of large mammals in Nimule National Park. Therefore, it is crucial to foster shared responsibilities and engage relevant stakeholders in the management and conservation of large wildlife species. Regular community awareness programs should be implemented to cultivate a sense of ownership. Moreover, it is recommended that a comprehensive survey be conducted on the population status of all mammal species in Nimule National Park, including its surrounding Buffer Zone. Monitoring the impact of human activities on their behavior and habitats using satellite images should also be carried out at least every five to ten years. 展开更多
关键词 diversity of Large Mammals abundance and Distribution IMPACTS Biodiversity Conservation Human Activities Nimule National Park South Sudan
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Impacts of Human Activities and Season on Species Diversity and Abundance of Butterflies in Mpanga Kipengere Game Reserve and Surrounding Farmlands, Tanzania
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作者 Privatus M. Kasisi Nsajigwa Mbije Paul Lyimo 《Open Journal of Ecology》 2024年第4期274-291,共18页
Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing distur... Maintaining natural habitats is crucial for the preservation of insects and other species that indicate environmental changes. However, the Mpanga/Kipengere Game Reserve and its surrounding farmlands are facing disturbance due to human activities, which is putting many wildlife species, particularly larger mammals, at risk. To determine the impact of human activities on butterfly species diversity and abundance in the reserve and its surrounding areas, we conducted a study from November 2021 to October 2023. We collected butterfly data using transect walks and baited traps in two habitat types. Our study yielded 2799 butterfly Individuals ranging in 124 species divided into five families habitat, season, and anthropogenic factors are significant environmental variables influencing species diversity and abundance of butterflies. Therefore, it’s important to protect habitat and dry-season water for the conservation of invertebrates such as butterflies. Our study findings provide essential information for ecological monitoring and future assessment of the Mpanga/Kipengere Game Reserve ecosystem health. 展开更多
关键词 Mpanga Kipengere Game Reserve Species diversity HABITAT Butterflies SEASON Human Activities
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Species Diversity and Abundance Distribution of Pelagic Siphonophores in Nan Wan Bay of Taiwan, China, in Late Autumn and Early Winter
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作者 张金标 黄将修 +1 位作者 连光山 唐森铭 《Marine Science Bulletin》 CAS 2005年第2期30-40,共11页
Zooplankton surveys were carried out on November 2-3 and December 8-10, 2001 at 12 stations in the Nan Wan Bay of Taiwan, China. Altogether 92 quantitative zooplankton samples were collected from subsurface water and ... Zooplankton surveys were carried out on November 2-3 and December 8-10, 2001 at 12 stations in the Nan Wan Bay of Taiwan, China. Altogether 92 quantitative zooplankton samples were collected from subsurface water and bottom water layers with two conical plankton nets (180 cm in length, 45 cm in opening diameter, 333μm and 200 larn in mesh size). A total of 31 species of Siphonophores were identified, among them 7 species are new records in the waters around Taiwan Island, of which Rocacea cymbiformis is a new record in China. Dominated by Chelophyes appendiculata, Bassia bassensis, Diphyes bojani, Diphyes dispar, Abylopsis eschscholtzi and Chelophyes contorta, these species accounted for over 76 % and 63 % of the total abundance in November and December. The species number and Siphonophores abundance in December (25 species, 1.99 inds/m3) were more than those in November (19 species, 0.438 inds/m3), and they were more in the surface water layer than in the bottom layer at most sampling stations. In early winter, the offshore high salinity water mass was a main factor influencing the distribution. The sampling efficiency for two plankton nets is discussed and the seasonal variation of species number and abundance in the Nan Wan Bay is compared with that in the neighboring waters. 展开更多
关键词 marine zooplankton Siphonophores species diversity abundance distribution TAIWAN Nan Wan bay
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An ecological survey of the abundance and diversity of benthic macrofauna in Indonesian multispecific seagrass beds 被引量:3
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作者 LIN Junhui HUANG Yaqin +7 位作者 ARBI Ucu Yanu LIN Heshan AZKAB Muhammad Husni WANG Jianjun HE Xuebao MOU Jianfeng LIU Kun ZHANG Shuyi 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第6期82-89,共8页
Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant spec... Seagrasses are one of the most productive ecosystems in coastal areas and support a wide variety of associated fauna. The tropical Indo-Pacific region is considered to have the highest diversity of seagrass plant species and the largest distribution areas of seagrass, yet the seagrass macrofauna in this region are poorly understood. To help fill this gap in our knowledge, an ecological survey was conducted to describe the abundance and diversity of benthic macrofauna from tropical seagrass beds and to determine between-station variations within a transect and between-site variations in macrofaunal abundance, taxa richness and community structure. Benthic macrofaunal samples associated with seagrass beds were collected with a core sampler on the east coast of North Sulawesi in May 2014 and on the west coast in October 2015. A total of 149 species from 14 higher taxa was collected. The most species-rich groups were polychaetes(56 species, 26% of total individual numbers), decapods(20 species, 9% of total numbers) and amphipods(18 species, 35% of total numbers). Between-station variations within a transect displayed different patterns between the east coast and the west coast. On the east coast, there were marked variations in abundance between stations within a transect for the macrofauna and amphipod assemblages. Both taxa richness and abundance varied with station for the macrofauna and polychaete assemblages on the west coast, resulting from the heterogeneity of the substrate along a transect. One-way ANOSIM together with MDS ordination indicated that macrofaunal community structure in seagrasses differed significantly between the east coast and the west coast, corresponding with the division of seagrasses into two broad categories of habitats, i.e.,mangrove-seagrass-reef continuum and seagrass-reef continuum. Compared with other studies in tropical areas,the abundance and diversity of benthic macrofauna in the present study were moderate. The reason for the two markedly distinct macrofaunal communities might be attributed to multiple factors, including sediment pattern,seagrass structure and temporal changes. 展开更多
关键词 benthic macrofauna diversity abundance community structure seagrass bed North Sulawesi
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Impact of Removal of Copper Leaf (<i>Acalypha fruticosa</i>Forssk.) on Plant Species Diversity and Abundance at Chemeron, Baringo County, Kenya 被引量:1
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作者 George Morara Ogendi Rhoda N. Ondieki Tabitha W. Njoroge 《Open Journal of Ecology》 2020年第6期341-355,共15页
Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. ... Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. The direct effects may include a reduction in the abundance and diversity of palatable plant species that constitute important forage for livestock, wildlife, and medicines for the local communities. Declines in ecosystem resilience are of the notable indirect effects of invasive species. The aim of this study was to assess the impacts of a plant species, copper leaf (<em>Acalypha fruticosa</em>) on floral diversity and abundance at Chemeron, Baringo County in Kenya. The study was guided by three questions: What is the plant composition in terms of grasses, herbs, shrubs, and trees in the study area? Are there any variations in plant abundance between the two sites (sites with and without <em>Acalypha fruticosa</em>)? Are there variations in plant species diversity between the two study sites? Two sites (one with <em>A. fruticosa</em> and another two without this invasive species) were selected within the Chemeron Research Centre. Two belt transects measuring 100 m × 20 m on each site were laid parallel to each other. Plant samples were collected from five 1 m × 1 m quadrats that were laid at intervals of 20 m. The plant species or specimens were identified to the species level using available taxonomic keys. Various indices including Shannon-Wiener (<em>H</em>’), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (SDI) were calculated. All the diversity, richness and evenness indices were considerably higher in the site without <em>A. fruticosa</em> compared to that where this invasive species was present. Higher <em>H’</em> (3.14 to 3.21) and SDI (0.93 to 0.94) values were noted in sites without the invasive species compared to <em>H</em>’ (2.11 to 2.20) and SDI (0.77 to 0.85) in sites with <em>A. fruticosa</em> present. Out of the 47 plant species identified, 39 and 20 of them occurred in the site without and with <em>A. fruticosa</em>, respectively. Further, there were more grasses (<em>Aristida keniensis</em>, <em>Cynodon dactylon</em>, <em>Brachiaria lucrantha</em>, <em>Eragrostis racemosa</em>, and <em>Enteropogon macrostachyus</em>) in the site without <em>A. fruticosa</em> compared to that with the invasive plant. The plants were also more evenly distributed in the site without <em>A. fruticosa</em> compared to that where the invasive plant was present. We conclude that <em>A. fruticosa</em> has a significant effect on plant species abundance and diversity as well as distribution. Its removal created a favourable environment for the growth of a variety of grasses. We therefore recommend to the agro-pastoralists and rangeland managers that <em>A. fruticosa</em> be mechanically removed by uprooting from grazing lands so as to increase forage availability and quality in the rangelands of South-Baringo. 展开更多
关键词 Baringo Copper Leaf diversity Indices Invasive Species Plant diversity
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Archaeal diversity and abundance within different layers of summer sea-ice and seawater from Prydz Bay,Antarctica
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作者 MA Jifei DU Zongjun +4 位作者 LUO Wei YU Yong ZENG Yixin CHEN Bo LI Huirong 《Advances in Polar Science》 2014年第1期54-60,共7页
Fluorescence in-situ hybridization (FISH) and 16S rRNA gene clone library analyses were used to determine the abundance and diversity of archaea in Prydz Bay, Antarctica. Correlation analysis was also performed to a... Fluorescence in-situ hybridization (FISH) and 16S rRNA gene clone library analyses were used to determine the abundance and diversity of archaea in Prydz Bay, Antarctica. Correlation analysis was also performed to assess links between physicochemical parameters and archaeal abundance and diversity within the sea-ice. Samples of sea-ice and seawater were collected during the 26th Chinese National Antarctic Research Expedition. The results of FISH showed that archaea were relatively abundant within the top layer of the sea-ice, and correlation analysis suggested that the concentration of 4NH+ might be one of the main factors underlying this distribution pattern. However, using 16S rRNA gene libraries, archaea were not detected in the top and middle layers of the sea-ice. All archaeal clones obtained from the bottom layer of the sea-ice were grouped into the Marine Group I Crenarchaeota while the archaeal clones from seawater were assigned to Marine Group I Crenarchaeota, Marine Group II Euryarchaeota, and Marine Group III Euryarchaeota. Overall, the ifndings of this study showed that the diversity of archaea in the sea-ice in Prydz Bay was low. 展开更多
关键词 ANTARCTICA summer sea-ice ARCHAEA diversity abundance
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Population Density, Diversity and Abundance of Antelope Species in Kainji Lake National Park, Nigeria
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作者 Olajesu Sunday Oladipo Akinyemi Abiodun Folorunso +1 位作者 Lateef Funmilayo Lewiska Lameed Gbolagade Akeem 《Open Journal of Ecology》 2019年第4期107-116,共10页
Habitat degradation and fragmentation are eating deep into conservation areas and this is a serious threat to species diversity and abundance. Species like the antelopes have a sedentary and docile nature which makes ... Habitat degradation and fragmentation are eating deep into conservation areas and this is a serious threat to species diversity and abundance. Species like the antelopes have a sedentary and docile nature which makes them highly vulnerable to habitat degradation or human intrusion. The effect becomes complex as the remaining flora and fauna communities can be significantly impacted by changes in ecosystem structure and function. Population density, diversity and abundance of fauna species will either increase or decrease over time depending on the quality of the environment/habitat and the level of human interference or disturbance. Hence an updated checklist of species diversity and abundance is necessary to enable management and other stakeholders make pragmatic plans and policy towards sustainable species conservation. With the aid of a Global Positioning System (GPS), a 5 km transect was established per site and censured for Antelope species using the King Census method of enumeration. Descriptive statistics and ANOVA was used to analyze the data. Seven (7) species of Antelopes were recorded. Kobs (Kobus kob) were the most abundant (2019), while Reedbuck (Redunca redunca) was the least abundant with twenty-five (25) individuals. Kob is the most observed species in Oli Complex with 24.13%, ranking about 50% of kob in proportion. This was followed by roan antelope (Hippotragus equinus), and Red Flanked duiker, 4.02% and 3.63% respectively. Kobs had the highest density of 40.38 per square km followed by roan antelope (3.32) and RF duiker (2.36). Relative density followed a similar trend. The least encounter rate was observed in Sylvicapra grimmia (0.02) and increse further to Hippotragus equinus (0.4), Redunca redunca (0.06) and Alcelaphus buselaphus (0.09) respectively. It was low amongst Tragelaphus scriptus (0.2), and moderate, while it was very high amongst the kobs (5.0). The rate of encountering an antelope in the park is very high at a rate of 6.2 animals per kilometer. Species of antelopes are almost not found in other ranges due to anthropogenic activities around the park. These activities are fast entering into the core area of the park. Hence management should take effective measure to curb this fast-rising problem. 展开更多
关键词 Kainji LAKE National PARK ANTELOPES Density diversity abundance
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Avian Abundance, Diversity and Conservation Status in Etago Sub-County Kisii County Kenya
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作者 Mokono M. Isaac Shadrack M. Muya +1 位作者 Winnie Kiiru Muchane Muchai 《Open Journal of Ecology》 2019年第5期157-170,共14页
Bird’s species diversity and abundance are being threatened due to agricultural activities and anthropogenic practices which causes habitat destruction and fragmentation. Understanding how avian species respond to ha... Bird’s species diversity and abundance are being threatened due to agricultural activities and anthropogenic practices which causes habitat destruction and fragmentation. Understanding how avian species respond to habitat destruction is important towards development of effective measures to ensure that the environment is protected. A study on avian abundance, diversity and conservation status was conducted in Etago Sub-County, Kisii County Kenya from September 2018 to February 2019. Point counts and time species counts were used to carry out birds’ survey to determine their abundance and diversity in the secondary forest, sugarcane plantations, human settlement and mixed firms. A total of 4992 individuals were observed and recorded in the entire study area. The human settlement had the highest density of 1.664 ± 0.18 birds/ha followed by sugarcane plantation with 1.092 ± 0.16 birds/ha and Nyangweta secondary forest was third with 0.0819 ± 0.13. Mixed firms had the least density of 0.95 ± 0.017 bird/ha. Further Dunn’s multiple comparisons test showed that Mixed farming and forest had no significant difference and had mean rank difference of 11.37. In mixed farming vs human settlement there was a significant difference with a mean rank difference of 57.38;in mixed farming vs sugarcane farms there was no significant difference;in the four habitats, 114 species of birds were cumulatively recorded. Out of these, 106 species were recorded in the secondary forests, 98 human settlement and 87 species in the sugarcane plantations and 55 in mixed farms. There was a significant difference in bird diversity in the four habitats where Secondary forest had the highest diversity of 3.85 and sugarcane plantations had a diversity of 3.71 while human settlement and mixed firms had lower diversities of 2.6 and 2.5 respectively (df1 = 2, df2 = 0.0 F = 0.00001, P = 0.00001). 展开更多
关键词 Density SIMILARITY diversity abundance Richness
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Species Distribution, Diversity, and Abundance of Sea Cucumbers in Tropical Intertidal Zones of Aurora, Philippines
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作者 Maria Cristina B. Cañada Michelle A. Resueño Eusebio V. Angara 《Open Journal of Ecology》 2020年第12期768-777,共10页
The distribution, diversity, and abundance of sea cucumbers in intertidal zones of Aurora were studied from February to June 2013 to obtain baseline data. A one-hour timed-search survey covering an approximate one kil... The distribution, diversity, and abundance of sea cucumbers in intertidal zones of Aurora were studied from February to June 2013 to obtain baseline data. A one-hour timed-search survey covering an approximate one kilometer over a ten-meter wide area was conducted in six coastal municipalities to obtain a comprehensive list of sea cucumber species found in the zones. Only four sampling stations (Baler, Dipaculao, Dilasag, and Dingalan) were selected for belt transect survey, 50 × 50 m, based on the availability of coralline, sandy, muddy sand, and rocky habitats which were laid perpendicular and parallel to each intertidal zone. Timed-search survey revealed a total of 15 species of sea cucumbers distributed among two Orders (Order Aspidochirotida and Order Apodida) and four Families (Family Holothuriidae, Family Stichopodidae, Family Synaptidae, and Family Chirotidae) were recorded. <em>Synapta maculata</em> is most common and has widespread distribution. Belt-tranect surveys showed <em>Holothuria leucospilota</em> is among the most frequently occurring species both during day time (58%) and night time (75%). The Dilasag sampling station had the most diverse species (0.71) while the Dipaculao sampling station had the densest species of <em>Holothuria leucospilota</em> (10,014 in<span style="white-space:nowrap;">&#8729;</span>ha<sup><span style="white-space:nowrap;">&#8722;</span>1</sup>) and abundant (95.91%) species. 展开更多
关键词 Sea Cucumber DISTRIBUTION diversity abundance Intertidal Zone
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Seasonal variations in diversity and abundance of surface ichthyoplankton in the northern South China Sea
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作者 LI Kaizhi YIN Jianqiang +1 位作者 HUANG Liangmin LIN Zhaojin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第12期145-154,共10页
The objective of this study was to investigate the seasonal variations of ichthyoplankton diversity and abun-dance in the northern South China Sea based on the data collected during summer, winter and spring. In total... The objective of this study was to investigate the seasonal variations of ichthyoplankton diversity and abun-dance in the northern South China Sea based on the data collected during summer, winter and spring. In total, 95 taxa of larval fishes were identified. The greatest number of species was recorded in spring, followed by summer and winter. The number of species was distributed mainly in the coastal waters from the east of Leizhou Peninsula to the southeast of Hainan Island during the surveyed periods of summer and spring, but in the offshore waters during winter. The abundance of larval fish was lowest in winter, increased in spring, and reached the maximum in summer. High abundance of larval fish was generally restricted to coastal waters with the isobaths less than 50 m. Seasonal variations of larval fish richness, abundance and diversity index were significant (P〈0.001). Carangidae was the most common and abundant taxon in summer and winter, whileSardinella sp.,Thrissa mystax andLeiognathus sp. were dominant in spring. High diversity and abundance of larval fish might be attributed to increased temperature and coastal upwelling in spring and summer. 展开更多
关键词 species composition abundance ICHTHYOPLANKTON CARANGIDAE northern South China Sea
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Assessment of Tree Diversity and Abundance in Rashad Natural Reserved Forest, South Kordofan, Sudan
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作者 Khalid A E Eisawi Hong He +1 位作者 Tayyab Shaheen Emad H. E. Yasin 《Open Journal of Forestry》 2021年第1期37-46,共10页
This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> ... This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> </b><span style="font-family:Verdana;">m) were taken randomly, and parameters were determined: </span><span style="font-family:Verdana;">trees</span><span style="font-family:Verdana;"> species diversity, composition, relative density, dominance, important value index, and species richness in the Rashad forest reserve. The results show that a total of 237 and 56 tree species, including 22 families, have been identified in the study area. Fabaceae family and species numbers have the highest number of 13 species in 8 genera, followed by Combretaceae with 8 species belonging to 3 different genera, Malvaceae with 5 species belonging to 4 different genera, Apocynaceae with 3 species belonging to 3 different genera. The Arecaceae, Burseraceae, Capparaceae, Euphorbiaceae, Meliaceae, and Rubiaceae families each had two species, and all the other 11 families had one species each. Among the 56 different tree species found within the reserve. The results also indicated that </span><i><span style="font-family:Verdana;">Tamarindus indica</span></i><span style="font-family:Verdana;"> L</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Ziziphus </span><span style="font-family:Verdana;">spina</span></i><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">christi</span><span style="font-family:Verdana;"> (L.) Desf. had the highest relative density and dominance of 4.64% and 11% respectively. </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Grewia </span><span style="font-family:Verdana;">villosa</span></i><span style="font-family:Verdana;"> Willd, </span><i><span style="font-family:Verdana;">Vepris </span><span style="font-family:Verdana;">nobilis</span></i><span style="font-family:Verdana;"> (Delile) Mziray had density and dominance of 4.80% and 9%.</span><b> </b><span style="font-family:Verdana;">Followed by </span><i><span style="font-family:Verdana;">Anogeissus </span><span style="font-family:Verdana;">leiocarpa</span></i><span style="font-family:Verdana;"> (DC.) Guill. & Perr, </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Catunaregam </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Tirveng. (Syn: </span><i><span style="font-family:Verdana;">Xeromphis </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Keay, </span><i><span style="font-family:Verdana;">Vangueria madagascariensis</span></i><span style="font-family:Verdana;"> J. F. Gmel. with 3.38% and 8%, respectively.</span><b> </b><span style="font-family:Verdana;">Eleven species recorded the least relative dominance of 0.42%.</span><b> </b><span style="font-family:Verdana;">Shannon-Weiner diversity index (H’) value stood at 3.82. And as diversity indices varied with location depending on the species available within an ecological zone, </span><span style="font-family:Verdana;">Rashad</span><span style="font-family:Verdana;"> forest reserve is blessed with a moderate diversity index. 展开更多
关键词 ASSESSMENT Tree Species diversity Rashad Natural Reserved Forest Relative Density Relative Dominance Importance Value Index
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Butterfly Species Diversity and Abundance in University of Ibadan Botanical Garden, Nigeria 被引量:3
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作者 Abideen Abiodun Alarape James Kehinde Omifolaji Georgina Samuel Mwansat 《Open Journal of Ecology》 2015年第8期352-360,共9页
Understanding the significance of butterflies in an ecosystem as an environmental healthy indicator and pollination of flowering plants is crucial to achieving sustainability and conservation of floral diversity. The ... Understanding the significance of butterflies in an ecosystem as an environmental healthy indicator and pollination of flowering plants is crucial to achieving sustainability and conservation of floral diversity. The aim of the study was to investigate the butterfly species diversity and abundance and compare the relationship between physical factor and butterfly species. Line transect were used to survey three habitats around botanical garden with scooped-net between June and July, 2010. Diversity varied from habitat to habitat. A checklist was made comprising a total of 57 butterfly species that were surveyed belonging to 9 families. There was a relationship between temperature and butterfly species diversity and abundance. There was no correlation between physical factors (relative humidity and temperature) and the total number of species and families. Moreover, butterfly numbers were not related to relative humidity in any species and family. However, temperature was significantly correlated with species. Therefore, understanding of the factors that affect butterfly species diversity and abundance in University of Ibadan Botanical Garden is important for conservation. 展开更多
关键词 BUTTERFLY Species BOTANICAL GARDEN diversity
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Invasive Species <i>Echinochloa colona</i>Reduces Abundance and Diversity of Resident Plant Communities in Tropical Wetland
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作者 Samora M. Andrew 《Open Journal of Ecology》 2018年第9期483-494,共12页
Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species ... Although the relationship between invasive alien species (IAS) and plant community structure has attracted considerable interest, the impacts of IAS on abundance and diversity of resident plant communities in species rich-ecosystems, such as tropical wetlands are poorly understood. Consequently, this has impeded development of improved management strategies and successful restoration of invaded tropical wetlands. Therefore, data on vegetation were collected from 60 plots of 20 × 50 m to study the impacts of alien invasive grass Echinochloa colona (L.) Link abundance on plant community abundance, richness, evenness and diversity of resident plant species within grasslands of the Kilombero Valley wetland, Tanzania. Moreover, the impacts of abundance of E. colona on plant functional groups (i.e. graminoids, forbs and shrubs) richness were also explored. Generalized linear models showed that community richness, evenness, diversity and abundance of resident species were negatively related to the E. colona abundance. There was a negative relationship between richness of graminoids and shrubs and the abundance of E. colona. Similarly, the abundance of graminoids, forbs and shrubs is related negatively to the abundance of E. colona. Given that most of the community and functional group attributes of resident plants is related negatively to E. colona abundance, improved management strategies should be developed to minimize the abundance and further spread of E. colona to restore and conserve wetland biodiversity. 展开更多
关键词 Native SPECIES EVENNESS Richness diversity Functional Groups RESIDENT SPECIES
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Abundance and Fluctuation in Spider Diversity in Citrus Fruits from Located in Vicinity of Faisalabad Pakistan
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作者 Maqsood I Mohsin S B +6 位作者 Li Yi-jing Tang Li-jie Saleem K M Khalil U R Shahla A Aoun Bukhari S S Jamal 《Journal of Northeast Agricultural University(English Edition)》 CAS 2016年第2期59-64,共6页
Spiders for the present study were collected from different fruit gardens(i.e. citrus) located at various localities(i.e., Tehsil Samundri, Jaranwala, Tandlianwala and Faisalabad) of District Faisalabad, Pakistan.... Spiders for the present study were collected from different fruit gardens(i.e. citrus) located at various localities(i.e., Tehsil Samundri, Jaranwala, Tandlianwala and Faisalabad) of District Faisalabad, Pakistan. Spiders belonging to six families and 33 species were captured from the two fruit gardens during the one year of this study. The citrus fruits garden was found to be best populated habitat as compared to other fruit garden. These sites were sampled by using pitfall traps; each month for five consecutive days from September 2010 to March 2011. As a result, 1 054 specimens were captured representing six families viz: lycosidae, thomosidae, gnaphosidae, saltisidae, araneidae and clubionidae. Lycosidae was more abundant, while clubionidae was less diverse during the study. Maximum population fluctuation among the spider specimens showed during the months from September and October, while the least abundance of spider specimens was reordered during June, November and December. Maximum taxonomic diversity was recorded from September to November, with the peak in September. It was concluded during these three months, when the citrus and guava gardens were attacked by the most of the pest insects. During the months of July and November diversity was moderate and mutually comparable, while in June and December, it was the least. This study contributed to the identification of spider diversity in the agro-ecosystem which could be used in the biological pest control. 展开更多
关键词 diversity spider citrus population Pakistan gardens
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Diversity, Abundance and Distribution Patterns of Epibenthic Echinoderms in Dungonab Bay, Red Sea, Sudan
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作者 Abdelmoneim Karamalla Gaiballa 《Open Journal of Ecology》 2024年第4期366-380,共15页
The abundance, distribution and diversity of epibenthic echinoderm were investigated at Dungonab Bay in the Red Sea coastal water of the Sudan. Four permanent line transects were chosen. Eight (30 × 2) square met... The abundance, distribution and diversity of epibenthic echinoderm were investigated at Dungonab Bay in the Red Sea coastal water of the Sudan. Four permanent line transects were chosen. Eight (30 × 2) square metre belt transects along each permanent line transect at 20 metre intervals were used to collect data. The data were subjected to univariate and multivariate analyses. Spatial variations of epibenthic echinoderm abundance were assessed with one-way analysis of variance. Hierarchical agglomerative clustering was used to identify and illustrate the similarities in echinoderm abundance between line transects and between belt transects. Indices of richness (d), diversity (H'), evenness (J') and dominance (C) were used to explain the diversity of epibenthic echinoderm species. The distribution pattern of each echinoderm species was determined in each permanent line transect. A total of 986 individuals were recorded within sixteen species of epibenthic echinoderms in the four line transects. Holothuriidae was the dominant family (5 species and 342 individuals). The most abundant echinoderms species was Pearsonothuria graeffei (77 individuals, about 7.81%). Abundances intra-transects and intra-families were insignificant (f = 1.67, p = 0.183, df = 3 and f = 3.24, p = 0.083, df = 9, respectively). The highest values of Shannon-Wiener diversity index (H'), Pielou evenness index (J'), Margalef species richness index (d), and Simpson Dominance index (C) were 2.738, 0.9875, 2.791 and 0.07159, respectively. The distribution patterns of all species in the study transects varied between clumped and uniform, with the exception of Asthenosoma varium of the Echinothuridae family, which had clumped distribution patterns in all transects. The study concluded that Dungonab Bay supports rich and diverse communities of epibenthic echinoderms. 展开更多
关键词 SUDAN Red Sea ECHINODERM diversity abundance and Distribution
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The Potential of Agroforestry Species Diversity and Abundance in a Disturbed Forest Reserve of Ogun State, Nigeria
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作者 Ibrahim Ndaginna Abdullahi Mutiu O. Bada 《Open Journal of Ecology》 2024年第11期831-844,共14页
Nigeria’s deforestation rate is at an alarming level due to weak forest governance, losing about 80 kha of natural forest cover per annum every year to agricultural land expansion, conflicts, and illegal logging. The... Nigeria’s deforestation rate is at an alarming level due to weak forest governance, losing about 80 kha of natural forest cover per annum every year to agricultural land expansion, conflicts, and illegal logging. The expansion of agricultural land over other land use is over 50% and it is increasing. Agroforestry, as an option, offers a dynamic, ecologically based, natural resource management system that integrates forest trees into the agricultural landscape for the benefit of land users at all levels. This research aimed to assess the diversity and abundance of agroforestry tree species between the forest and farm zones at Edun Forest Reserve to improve agrobiodiversity by identifying tree species richness around farms in the reserve. A systematic sampling technique was used to sample plots, and relative dominance and important value index were determined. Results showed a significant difference between the species richness between the forest zone and farm zone of Edun Forest Reserve. On the important value index, Gmelina arborea (25.04) has the highest in the forest zone, while Cedrela odorata (0.661) is the least, and Tectona grandis (39.37) is the species with the highest in the farm zone Terminalia ivorensis (2.91) recorded the least. Combretaceae was identified as the most dominant family across the two zones. This research showed that appraisal of tree stand structure on farmlands is crucial for sustainable agroforestry management decisions in the forest zones of Nigeria. 展开更多
关键词 Agroforestry Species diversity Land Use Gmelina
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Viromes of Haemaphysalis longicornis reveal different viral abundance and diversity in free and engorged ticks 被引量:1
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作者 Jian Xiao Xuan Yao +13 位作者 Xuhua Guan Jinfeng Xiong Yaohui Fang Jingyuan Zhang You Zhang Abulimiti Moming Zhengyuan Su Jiayin Jin Yingying Ge Jun Wang Zhaojun Fan Shuang Tang Shu Shen Fei Deng 《Virologica Sinica》 SCIE CAS CSCD 2024年第2期194-204,共11页
Haemaphysalis longicornis ticks,commonly found in East Asia,can transmit various pathogenic viruses,includingthe severe fever with thrombocytopenia syndrome virus(SFTSV)that has caused febrile diseases among humansin ... Haemaphysalis longicornis ticks,commonly found in East Asia,can transmit various pathogenic viruses,includingthe severe fever with thrombocytopenia syndrome virus(SFTSV)that has caused febrile diseases among humansin Hubei Province.However,understanding of the viromes of H.longicornis was limited,and the prevalence ofviruses among H.longicornis ticks in Hubei was not well clarified.This study investigates the viromes of bothengorged(fed)and free(unfed)H.longicornis ticks across three mountainous regions in Hubei Province from 2019to 2020.RNA-sequencing analysis identified viral sequences that were related to 39 reference viruses belonging tounclassified viruses and seven RNA viral families,namely Chuviridae,Nairoviridae,Orthomyxoviridae,Parvoviridae,Phenuiviridae,Rhabdoviridae,and Totiviridae.Viral abundance and diversity in these ticks were analysed,andphylogenetic characteristics of the Henan tick virus(HNTV),Dabieshan tick virus(DBSTV),Okutama tick virus(OKTV),and Jingmen tick virus(JMTV)were elucidated based on their full genomic sequences.Prevalenceanalysis demonstrated that DBSTV was the most common virus found in individual H.longicornis ticks(12.59%),followed by HNTV(0.35%),whereas JMTV and OKTV were not detected.These results improve our understanding of H.longicornis tick viromes in central China and highlight the role of tick feeding status and geographyin shaping the viral community.The findings of new viral strains and their potential impact on public health raisethe need to strengthen surveillance efforts for comprehensively assessing their spillover potentials. 展开更多
关键词 TICKS Virome Haemaphysalis longicornis Phylogenetic analysis Viral abundance and diversity
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Diversity and Abundance of Amenity Trees in the Premises of International Institute of Tropical Agriculture(IITA),Ibadan,Nigeria
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作者 Yewande Owoeye Stefan Hauser 《Journal of Botanical Research》 2023年第4期1-10,共10页
Amenity trees are an essential element of most urban communities,contributing significantly to human well-being and improving environmental quality.Good knowledge of the diversity and abundance of trees in our environ... Amenity trees are an essential element of most urban communities,contributing significantly to human well-being and improving environmental quality.Good knowledge of the diversity and abundance of trees in our environment and their importance can help promote conservation,which is essential for sustainability.This study aimed at assessing the diversity and abundance of amenity trees on the premises of the International Institute of Tropical Agriculture(IITA),Ibadan Nigeria.The institute was divided into working and residential areas.The trees in the study area were identified using a walking and windshield survey.A total population of 2626 trees from 126 species and 42 families were identified on the premises of IITA.The highest tree population of 523 trees was recorded in the Tropical Crescent residential area with 321 trees of Lagerstroemia speciosa being the most frequent species.Across working and residential areas,Elaeis guineensis was the most frequent species accounting for 19.92%of the total tree population.A Shannon-Wiener Diversity Index(H’)of 3.383 and species evenness of 0.43 was obtained from the study area.The high values of diversity indices obtained indicate that IITA premises are rich in diverse tree species both indigenous and exotic hence should be referenced as a good urban landscape.The current management practices can be recommended for other institutions. 展开更多
关键词 Amenity trees Species diversity abundance IITA Ibadan
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Thriving green havens in baking deserts:Plant diversity and species composition of urban plantations in the Sahara Desert
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作者 Mohammed SOUDDI Haroun CHENCHOUNI M'hammed BOUALLALA 《Journal of Arid Land》 SCIE CSCD 2024年第9期1270-1287,共18页
Hot arid zones represent vital reservoirs of unique species and ecosystems,holding significant importance for biodiversity.This study aimed to explore the plant diversity associated with tree plantations in urban ecos... Hot arid zones represent vital reservoirs of unique species and ecosystems,holding significant importance for biodiversity.This study aimed to explore the plant diversity associated with tree plantations in urban ecosystems under hyper-arid climatic conditions in the Sahara Desert of Algeria.In May 2022,30 quadrats measuring 1 m^(2) each were established at the base of Phoenix dactylifera,Leucaena leucocephala,and Tamarix aphylla,corresponding to the dominant tree species in each of three plantations.In each quadrat,the plant quantitative inventory was conducted to measure plant diversity and similarity among the studied plantations.Based on this,we assessed the plant functional traits and rarity/abundance status of the flora.The findings revealed a diverse flora associated with the studied plantations,comprising 29 plant species grouped into 27 genera and 12 families.Notably,Poaceae(accounting for 30.8% of the flora),Asteraceae(25.0%),and Zygophyllaceae(21.6%)were well-represented.With an overall density of approximately 555 individuals/m^(2),Zygophyllum album(120 individuals/m^(2))and Polypogon monspeliensis(87 individuals/m^(2))emerged as the most abundant species.Functional trait analysis underscored the pivotal role of therophytes(constituting over 50.0% of the flora)and anemochorous species(33.0%-62.5%).Phytogeographic analysis emphasized the prevalence of the Saharo-Arabic element(constituting over 31.0% of the flora)and the Mediterranean Saharo-Arabic element(9.5%-21.5%).The Cosmopolitan element thrived under disturbance factors,recording percentages from 13.0% to 20.0% of the plant community.The rarity/abundance status of the flora emphasized the significance of rare,common,and very common species in the studied plantations.These findings could provide fundamental data for the effective control and management of biodiversity in hot hyper-arid urban ecosystems. 展开更多
关键词 urban plantations plant diversity plant functional traits rarity/abundance status Sahara Desert Algeria
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