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Regeneration ecology and population status of a critically endangered and endemic tree species (Ilex khasiana Purk.) in north-eastern India 被引量:2
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作者 Upadhaya Krishna Barik Saroj Kanta +2 位作者 Adhikari Dibyendu Baishya Ratul Lakadong Nigyal John 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第3期223-228,共6页
Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillo... Detailed studies on population structure and regeneration ecology ofllex khasiana were carried out at five representative natural populations i.e. Mylliem (Population - I), Upper Shillong (Population - II), Shillong Peak (Population -III), Laitkor (Population - IV) and Nongpiyur (Population - V) to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions (full sunlight (100%), intermediate sunlight (50%) and low sunlight (30%)) showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees (〉Scm dbh) exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species. 展开更多
关键词 Ilex khasiana endangered species population status REGENERATION north-eastern India
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Regeneration ecology and population status of a critically endangered and endemic tree species (Ilex khasiana Purk.) in north-eastern India
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作者 Upadhaya Krishna Barik Saroj Kanta +2 位作者 Adhikari Dibyendu Baishya Ratul Lakadong Nigyal John 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A3期223-228,286,共7页
Detailed studies on population structure and regeneration ecology of Ilex khasiana were carried out at five representative natural populations i.e. Mylliem (Population–I), Upper Shillong (Population–II), Shillong Pe... Detailed studies on population structure and regeneration ecology of Ilex khasiana were carried out at five representative natural populations i.e. Mylliem (Population–I), Upper Shillong (Population–II), Shillong Peak (Population–III), Laitkor (Population–IV) and Nongpiyur (Population–V) to probe into the responsible affecting factors for its population structure and regeneration ability in these populations. Experimental observation under three controlled light conditions (full sunlight (100%), intermediate sunlight (50%) and low sunlight (30%)) showed that the growth status and survival rates of seedlings under intermediate and low light were better than those under the high light condition. The density-diameter distribution in population of adult trees (≥5cm dbh) exhibited a typical character of a regenerating population. A higher seedling mortality rate in natural populations of I. khasiana was most probably due to increase in light intensity following vegetation destruction and other anthropogenic disturbances that cause opening of forest canopy. The findings of the present study would be of immense value in formulating appropriate conservation measures for the species. 展开更多
关键词 Ilex khasiana endangered species population status REGENERATION north-eastern India
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Population Status, Threats and Conservation of the Spotted Pond Turtle;Geoclemys Hamiltonii (Gray, 1830) (Geoemydidae) of Pakistan
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作者 Amtyaz Safi Muhammad Zaheer Khan +1 位作者 Roohi Kanwal Hans-Volker Karl 《Journal of Zoological Research》 2021年第1期29-37,共9页
In the present work on population status,threats and conservation of the spotted pond turtle;Geoclemys hamiltonii(Gray,1830)(Geoemydidae)was conducted in Thatta,Sujawal and Badin districts of Sindh province of Pakista... In the present work on population status,threats and conservation of the spotted pond turtle;Geoclemys hamiltonii(Gray,1830)(Geoemydidae)was conducted in Thatta,Sujawal and Badin districts of Sindh province of Pakistan.A total number of 277 live specimens of G.hamiltonii from southeast province(Sindh)of Pakistan have been collected from different water bodies and sites in three consecutive year’s i.e 2015-2017.The population status of G.hamiltonii has recorded as decreasing in Sindh due to habitat destruction,eutrophication,agricultural farming and some other anthropogenic activities.This species is mostly used as pet and the poachers mostly carrying this species for trade in East Asian countries.The globally illegal trading hubs of this species are Bangkok,Taiwan and Hong Kong.More and powerful actions and efforts are needed to raise awareness of smuggling of wildlife,with a specific need of formal memorandums of understanding(MOUs)are strongly encouraged south Asian and east Asian countries to control illegal trade between the countries and territories along the trade route of Bangladesh,India,Pakistan,Thailand,Hong Kong and Taiwan to improve cross border enforcement. 展开更多
关键词 population status Threats CONSERVATION Geoclemys hamiltonii
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Population Status and Trend of the Maasai Ostrich in the Mid Kenya—Tanzania Borderland
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作者 Moses Makonjio Okello John Warui Kiringe +12 位作者 Lekishon Kenana Fiesta Warinwa Hanori Maliti Noah Wasilwa Sitati Erastus Kanga Samwel Bakari Stephen Ndambuki Philip Muruthi Nathan Gichohi Edeus Massawe David Kimutai Machoke Mwita Daniel Muteti 《Natural Resources》 2016年第10期558-579,共22页
The Maasai ostrich (Struthio camelus) is a the largest avian species in East Africa and though it’s not considered to be a species of conservation concern, some populations are on the decline and this is attributed t... The Maasai ostrich (Struthio camelus) is a the largest avian species in East Africa and though it’s not considered to be a species of conservation concern, some populations are on the decline and this is attributed to bush meat activities, predation on their eggs illegal consumption by humans, habitat destruction and forage competition with other large wildlife species. Climate change is also emerging to be another major threat due to interference with food availability which in turn interferes with the breeding rhythm. Thus, this study examined the population status, trend and distribution of the Maasai ostrich in the Southern Kenya and Northern Tanzania borderland after the 2007 to 2009 drought. The results showed that the species was found across the entire borderland but the Amboseli region had the highest number and density of Maasai ostrich (726.00 ± 100.9;0.08 ± 0.01 ostriches per km<sup>2</sup>), followed by Lake Natron area (330.8 ± 69.8;0.05 ± 0.01 ostriches per km<sup>2</sup>) and the least was in West Kilimanjaro (85.5 ± 18.0;0.03 ± 0.01 ostriches per km<sup>2</sup>). Drought caused a decline in the population of the Maasai ostrich but the Amboseli area experienced the highest decline in density (?13.44 ± 12.61) compared to other borderland sectors. However, the populations increased in most sectors after the drought, and wet season numbers and densities were higher than the dry season. The highest positive increase in number and density was in Lake Natron area (+85.65 ± 91.06) followed by West Kilimanjaro (+68.39 ± 59.54), and the least was in the Magadi area (+22.26 ± 32.05). There is a need to enhance conservation of avian species like the Maasai ostrich other than just focusing on the charismatic species such as the African elephant and black rhino. We therefore recommend joint collaboration in monitoring all large wildlife populations across the Kenya-Tanzania borderland with a view of understanding their status, trend and best management actions that can enhance their conservation. 展开更多
关键词 BORDERLAND Kenya Maasai Ostrich population Trend and status Tanzania
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Post Drought Population Status and Trend of Specialized Browsers in the Mid Kenya-Tanzania Borderland
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作者 Moses Makonjio Okello John Warui Kiringe +12 位作者 Philip Muruthi Lekishon Kenana Hanori Maliti Noah Wasilwa Sitati Erastus Kanga Fiesta Warinwa Samwel Bakari Stephen Ndambuki Nathan Gichohi Edeus Massawe David Kimutai Machoke Mwita Daniel Muteti 《Natural Resources》 2016年第10期580-610,共31页
We examined the population status, trend and distribution of Gerenuk, Fringe-eared Oryx and Lesser kudu in the Northern Tanzania and Southern Kenya borderland after the 2007 to 2009 drought. The species were character... We examined the population status, trend and distribution of Gerenuk, Fringe-eared Oryx and Lesser kudu in the Northern Tanzania and Southern Kenya borderland after the 2007 to 2009 drought. The species were characterized by low numbers and sparsely distributed in the borderland but were more prevalent and abundant in the Amboseli region. However, West Kilimanjaro had the highest positive change in density between 2010 and 2013 [Gerenuk = +1650.48 ± 1150.31, lesser kudu = +912.78 ± 487.63 and Fringe-eared Oryx = +366.65 ± 233.32]. Changes in density and composition varied seasonally among the different sectors of the borderland, with Gerenuk having the highest change in the Amboseli area during the wet season. Lesser kudu had the highest change in Amboseli and Kilimanjaro during the wet season while Fringe-eared Oryx had the highest change in the wet season in West Kilimanjaro area. Spatial distribution of the species varied seasonally and across different sectors of the borderland. In the dry season, Gerenuk exhibited a clumped distribution mainly in Amboseli National Park, and between Natron and West Kilimanjaro but in the wet season, it spread out more though higher concentrations were still found Amboseli and West Kilimanjaro. Lesser concentrated in mostly in West Kilimanjaro and Amboseli during the dry season but was widely dispersed during the wet season. Similarly, during the dry season, the Fringe-eared Oryx was confined in the Amboseli and West Kilimanjaro areas but during the wet season, it much more spread out with clusters in the Mbirikani area of the Amboseli region and a few places in Magadi, Natron and West Kilimanjaro. Management implications of the findings obtained in this study area here-in discussed. 展开更多
关键词 BORDERLAND Fringe-Eared Oryx Gerenuk Kenya Lesser Kudu population Trend and status Tanzania
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Diversity, regeneration status and population structure of gum-and resin-bearing woody species in south Omo zone, southern Ethiopia
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作者 Muhamed Adem Adefires Worku +2 位作者 Mulugeta Lemenih Wubalem Tadesse Jürgen Pretzsch 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期319-328,共10页
South Omo Administrative Zone in Ethiopia is home to 18 indigenous ethnic groups whose livelihood is vulnerable due to recurrent drought and degradation. Despite the preliminary observation showing the rich dry-forest... South Omo Administrative Zone in Ethiopia is home to 18 indigenous ethnic groups whose livelihood is vulnerable due to recurrent drought and degradation. Despite the preliminary observation showing the rich dry-forest resource base that, if sustainably managed could enhance livelihoods and biodiversity conservation, there is lack of empirical data on its current status. We conducted a study aiming at quantifying the population status of gum- and resin-bearing species in two randomly selected districts, Hamer and Bena-Tsemay. Seventy-five quadrats (35 at Hamer and 40 at Bena-Tsemay) each measuring 400 m2 were established along line transects to assess species diversity and equitability, density, frequency, dominance, importance value and population structure. We recorded a total of 27 woody species of 12 families and 14 genera. Fifteen species (9 at Hamer and 14 at Bena-Tsemay) of the genera Acacia, Boswellia, Commiphora and Sterculia, were identified as either major sources of commercial gums and resins or their adulterants. Gum- and resin-bearing species comprised 56% and 57% of species richness, 48% and 50% of total density per ha, 95% and 98% of basal area, and 64% and 56% of importance values at Hamer and Bena-Tsemay, respectively. Diversity of the entire woody species assemblage and of the gum- and resin-bearing species was slightly higher at Bena-Tsemay (H= 2.61, 1.4) than at Hamer (H'= 2.48, 1.28), respectively. The diversity and abundance of the resource base suggest potential for development of value-added commercialization of gum and resins to enhance livelihoods and encourage sustainable management of the forest at these study areas. We recorded, however, declining natural regeneration of most gum- and resin-bearing species, and this calls for integrated and participatory species management and landscape rehabilitation. 展开更多
关键词 ACACIA BOSWELLIA COMMIPHORA STERCULIA gum and resins population status southern Ethiopia
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Blue-eared Pheasant:a forest bird endemic to China
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作者 吴逸群 刘廼发 《Chinese Birds》 2011年第4期200-205,共6页
The Blue-eared Pheasant (Crossoptilon auritum) is an important bird species,endemic to China and is ranked as a second grade key protected wildlife species in China.These birds are only found in the mountainous region... The Blue-eared Pheasant (Crossoptilon auritum) is an important bird species,endemic to China and is ranked as a second grade key protected wildlife species in China.These birds are only found in the mountainous regions of Qinghai,Gansu and Sichuan provinces and the Ningxia Hui Autonomous Region.In order to understand systematically the existing information on the biology of the Blue-eared Pheasant,we provide updated information on its habitat,activity,nest-site features,breeding biology,feeding habits,population status and conservation of this pheasant by integrating published data with the information from our field surveys,conducted from 2006 to 2008 in the Gaihai-zecha National Nature Reserve,Gansu. 展开更多
关键词 Blue-eared Pheasant HABITAT breeding biology feeding habits population status
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Abundance and Breeding of the Common Skittering Frog(Euphlyctis cyanophlyctis)and Bull Frog(Hoplobatrachus tigerinus)at Rawal Lake,Islamabad,Pakistan
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作者 Fozia TABASSUM Muhammad RAIS +3 位作者 Maqsood ANWAR Tariq MEHMOOD Iftikhar HUSSAIN Shahid ALI KHAN 《Asian Herpetological Research》 SCIE 2011年第4期245-250,共6页
The population density and breeding of two frog species, i. e., the Skittering Frog (Euphlyctis eyanophlyctis) and the Bull Frog (Hoplobatrachus tigerinus) were studied at Rawal Lake, Islamabad, Pakistan, by using... The population density and breeding of two frog species, i. e., the Skittering Frog (Euphlyctis eyanophlyctis) and the Bull Frog (Hoplobatrachus tigerinus) were studied at Rawal Lake, Islamabad, Pakistan, by using visual encounter method from September 2009 to August 2010. Mean population density for the two frogs was 1.55 ± 0.44 frogs per ha, with that for the Skittering Frog being 1.09 ± 0.33 frogs/ha and that of the Bull Frog 0.46 ± 0.11 frog/ha, respectively. It is concluded that both frog species are explosive breeders, i. e., their breeding activities were confined to the first showers of the monsoon season. The mean spawn weight of the Skittering Frog was 1.5 g with more than 1000 eggs in each spawn, while that of the Bull Frog was 0.26 g with less than 1000 eggs in a spawn. The spawning sites of the two species were investigated in detail. Generally, no threat to their populations was observed. However, the opening of the spillway of Rawal Dam following the torrential rain destroyed the breeding sites of the frogs. It is maintained that the event did not produce any significant impact on their populations and breeding as the two species were quite common. 展开更多
关键词 RANIDAE population status BREEDING habitat destruction
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An Analysis of the Relationship Between the Education Attainment and Economic Status of the Elderly Population in the Towns and Cities of China
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作者 Sha Jicai Sha Jicai works in the Institute of Population Research,China Academy of Social Science 《China City Planning Review》 1990年第4期52-59,共8页
Viewed from a macro scope,the cultureof a community is closely related to its econ-omy.Economy being the basis,the level ofeconomic growth determines the level ofcultural development.Conversely,culturecan act as the p... Viewed from a macro scope,the cultureof a community is closely related to its econ-omy.Economy being the basis,the level ofeconomic growth determines the level ofcultural development.Conversely,culturecan act as the precursor and cultural devel-opment enhances economic growth.Likewise,the education attainment of an in-dividual reflects the same sort 展开更多
关键词 rate more An Analysis of the Relationship Between the Education Attainment and Economic status of the Elderly population in the Towns and Cities of China
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