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1.
The population dynamics of trout (Salmo trutta L.) were studied in two high-altitude streams flowing westwards into the River Eden in northern England. The results from one (Knock Ore Gill), which is accessible to spawners from downstream, were compared with published data from an isolated population in a nearby stream which flows eastward into the River Tees. The Knock Ore Gill trout had a population density of 0.4–0.9 fish m–2, a biomass of 12.4 g m–2, annual production of 12–14 g m–2 year–1 and an instantaneous mortality rate of 0.97 year–1. Comparable values from the Tees tributary were 0.2, 3.3, 2.3 and 0.66 respectively. The Knock Ore Gill population also contrasted with that of the Tees tributary in having reliable recruitment from year to year. These differences were related to differences in the chemistry and spate characteristics of the two streams and to the fact that immigrants from downstream were responsible for over 30% of the annual oviposition in Knock Ore Gill.  相似文献   

2.
The age, growth, population densities and annual production of an isolated population of brown trout ( Salmo trutta L.) and bullhead ( Coitus gobio L.) were investigated over a 5 year period in Trout Beck in the northern Pennines. Additional data were obtained from two other sites; Great Dodgen Pot Sike and the River Tees.
Trout growth rates were low, particularly in Dodgen Pot Sike, but ages up to VIII were recorded. Bullhead growth rates were similar to those in the Tees at Cow Green (Crisp et al. , 1974), though the Moor House bullheads had a higher survival rate. Population densities of trout ranged from 0.10–0.22/m2, with a fry contribution of 0.80%. The bullhead population in Trout Beck was sparse, generally 0.1/m2, though an 0 group value of 0.46/ma was estimated in 1967. At Tees Bridge values ranged from 2.5–7/8/m2. Most trout matured by age III, though in Great Dodgen Pot Sike only half of the females were mature at age IV.
Annual production was estimated from Allen graphs. Trout production ranged from 1.02–3.50 g/m2/year, the fry contributing up to 51.5% of the total. A value of 0.48 g/m2/year was obtained for bullheads in the Trout Beck system in a year of good recruitment, whilst bullhead production at Tees Bridge was 7.43 g/m2/year, with fry and I group contributing 48.7 and 37.5% respectively. The high survival rate, irregular recruitment, and poor growth of these high altitude populations is discussed. Growth and reproductive peculiarities of the Great Dodgen Pot Sike trout are also discussed.  相似文献   

3.
Guanshan National Nature Reserve (GNNR) is located in the middle reach of the Jiuling Mountain Range in the southern China and the first national nature reserve within Jiangxi Province. The fish fauna of mountain streams in the GNNR was investigated from September 2006 to August 2007. A total of 379 fish were collected and classified into two families and seven species. Acrossocheilus parallens [relative abundance (RA) 44.3%] was the most abundant fish species. Subdominant species were Onychostoma barbata (RA, 20.3%), Zacco platypus (RA, 14.2%) and Opsariichthys bidens (RA, 12.4%).A greater number of species (7 vs. 2) and individuals (295 vs. 84) were collected from the West Stream compared to the East Stream. Among the seven fish species collected in the GNNR, Acrossocheilus parallens, Onychostoma barbata and Vanmanenia stenosoma are endemic to the Chinese mountain streams. This study suggests that mountain streams in the nation reserves including GNNR are very important for freshwater fish diversity and conservation in Jiangxi Province.  相似文献   

4.
鼎湖山药用植物资源调查分析   总被引:4,自引:1,他引:4  
张宏伟  马骥   《广西植物》2005,25(6):539-543
经调查,鼎湖山国家自然保护区共有药用植物193科677属1 077种,含蕨类植物32科55属85种1 变种,裸子植物7科10属12种,被子植物154科612属979种;对其中具有特色的中草药作了重点介绍,并提 出合理开发利用及保护建议。  相似文献   

5.
2016年12月至2019年8月,利用红外相机技术在贵州大沙河国家级自然保护区内对陆生大中型兽类和鸟类进行调查.本次调查设置85个1 km×1 km的公里网格和114个相机位点,共计19950个相机工作日和10767张独立有效照片.鉴定出鸟兽12目35科86种,其中兽类有5目14科25种和鸟类有7目21科61种,有4种...  相似文献   

6.
Data from the long-term experiment on sheep grazing versus zero sheep grazing (i.e. in an enclosure) on the composition of the Juncus squarrosus grassland at the Moor House NNR are presented. The data have been analysed to assess change in (1) the abundance of individual species, (2) higher plant and bryophyte communities, and (3) vegetation structure. The higher plant data suggested that both the enclosed-and grazed plots were changing in the same direction, but the enclosed plot was moving much faster. The general tendency was towards a blanket bog vegetation dominated by Eriophorum vaginatum and Calluna vulgaris. Juncus squarrosus has declined very quickly in the enclosed plot, but there has also been a slower decline in the grazed one. A significant increase in Calluna vulgaris has occurred only in the enclosed plot. In contrast, the bryophyte data showed completely different successional trajectories in the two treatment plots.The vegetation structure changed markedly after release from grazing, with a decrease in phytomass, but increase in necromass in the lowest height strata. There was no noticeable change in structure over the 18 year period in the grazed plot.Particular problems found in this study were that some species either fluctuated widely in response, or changed in a curvilinear manner.  相似文献   

7.
正子午岭国家级自然保护区(35°45'–36°01'N,108°30'–108°41'E)位于陕西和甘肃两省交界的子午岭陕西境内,占地面积406.21 km~2,海拔1,100–1,687 m,地带性植被类型属华北暖温带落叶阔叶林。保护区内春季多风,夏季炎热,秋季多雨,冬季干旱。年均降水量588.7 mm,且主要集中在6–9月。年平均气温9.2℃,气温年较差25.9℃(刘淑明,  相似文献   

8.
2017年1月至2019年9月, 我们在广东云开山国家级自然保护区3个观测样区布设61台红外相机, 对兽类和鸟类多样性进行调查。共记录到野生兽类4目7科9种, 鸟类6目14科34种, 其中广东省新记录1种, 为蓝绿鹊(Cissa chinensis), 记录国家II级重点保护动物2种, 为原鸡(Gallus gallus)和白鹇(Lophura nycthemera)。相对多度较高的5种兽类依次为赤腹松鼠(Callosciurus erythraeus)、赤麂(Muntiacus vaginalis)、鼬獾(Melogale moschata)、野猪(Sus scrofa)和果子狸(Paguma larvata), 相对多度较高的3种鸟类分别是紫啸鸫(Myiophoneus caeruleus)、虎斑地鸫(Zoothera dauma)和红嘴相思鸟(Leiothrix lutea)。通过对相对多度指数前三的鸟兽日活动节律观察分析, 共发现4种典型昼行性动物(赤腹松鼠、紫啸鸫、虎斑地鸫和红嘴相思鸟)和1种典型夜行性动物(鼬獾)。赤麂日活动呈现两个高峰时段, 分别为12:00-14:00和18:00-20:00。本研究评估了广东云开山国家级自然保护区部分兽类和鸟类资源现状, 为保护区野生动物保护与管理提供了数据支持。  相似文献   

9.
刘芳  李迪强  吴记贵 《生态学报》2012,32(3):730-739
红外相机是监测野生动物的有效工具,目前广泛用于兽类资源调查以及动物损害、鸟巢生态学、种群评估、行为生态学等研究领域。为了调查北京松山国家级自然保护区的野生动物,于2010年5—12月采用红外相机进行系统调查,在210个位点放置了红外相机,每台相机在每个地点上放置一个月。研究期间共拍摄到照片2203张,其中73%为兽类,12%为鸟类,13%为工作人员,2%为其它人员。共鉴定出17种兽类(分属5目10科)以及36种鸟类(分属5目17科)。兽类中拍摄率最高的前5种动物分别是岩松鼠(Sciurotamias davidianus)、猪獾(Arctonyx collaris)、豹猫(Prionailurus bengalensis)、狗獾(Meles meles)和貉(Nyctereutes procyonoides),鸟类中拍摄率最高的前5种动物分别是紫啸鸫(Myophonus caeruleus)、雉鸡(Phasianus colchicus)、松鸦(Garrulus glandarius)、勺鸡(Pucrasia macrolopha)和宝兴歌鸫(Turdus mupinensis)。红外相机在不同海拔、不同植被类型以及不同月份所拍摄动物的拍摄率不同:在1000—1400m的海拔段,拍摄率显著高于低海拔(600—1000m)以及中高海拔(1400—1700m);在阔叶林中的拍摄率最高,在针叶林、针阔混交林和灌丛中的拍摄率相似;秋季(8—10月)拍摄率较高,夏季(6—7月)次之,冬季(11—12月)最低。红外相机拍摄到的累积物种数与相机放置的时间成上升曲线,但曲线的增长速率逐渐变缓。研究表明红外相机适合于调查和监测大中型兽类和部分鸟类,所采集的动物数据以及拍摄的图片和视频资料将为保护区的监测、科研和环境教育提供资料。讨论了应用红外相机调查和监测野生动物的技术细节。  相似文献   

10.
2015年1月至2017年12月, 在陕西佛坪国家级自然保护区57条巡护样线上布设130台红外相机, 对兽类和鸟类多样性进行调查。累计相机工作日101,220天, 共捕获独立有效事件36,100次, 其中兽类独立照片30,563张, 鸟类3,244张。共记录到野生兽类6目15科29种, 相对多度较高的前5个物种依次是秦岭羚牛(Budorcas bedfordi, RAI = 11.53)、野猪(Sus scrofa, RAI = 4.80)、小麂(Muntiacus reevesi, RAI = 4.35)、大熊猫(Ailuropoda melanoleuca, RAI = 1.81)和中国豪猪(Hystrix hodgsoni, RAI = 1.13)。共记录到鸟类8目14科54种, 相对多度最高的前5个物种依次是红腹锦鸡(Chrysolophus pictus, RAI = 0.97)、红腹角雉(Tragopan temminckii, RAI = 0.74)、紫啸鸫(Myophonus caeruleus, RAI = 0.51)、红嘴蓝鹊(Urocissa erythrorhyncha, RAI = 0.13)、黑领噪鹛(Garrulax pectoralis, RAI = 0.12)。保护区鸟类新记录4种, 包括白眉地鸫(Geokichla sibirica)、白眉鸫(Turdus obscurus)、长尾地鸫(Zoothera dixoni)和灰脸鵟鹰(Butastur indicus); 保护区兽类新记录1种, 为亚洲狗獾(Meles leucurus)。本研究利用红外相机技术客观记录了佛坪国家级自然保护区兽类和鸟类的本底情况, 不仅初步了解了保护区内的野生动物分布, 而且更新了保护区鸟类资源数据库, 为保护区未来的保护和管理工作提供了数据基础。  相似文献   

11.
基于实地考察、文献资料和标本数据,借助GIS技术构建桂西黔南生物多样性保护优先区的39种国家重点保护植物空间地理分布格局,结合30m空间分辨率遥感影像解译的植被与地表覆盖数据,研究该优先区内的国家重点保护物种的生境与植被类型的关系及保护现状,并就优先区国家重点保护植物的地理分布格局分析优先区以外的保护空缺。此外,对优先区近二十年来的植被与地表覆盖特征的时空变化进行分析研究,结果优先区的人居用地、湿地(包括水库)面积分别增加67.75km2和371.11km2,森林面积相对稳定,灌丛和草丛面积分别减少230.69km2和174.70km2。该地区的国家重点保护植物正面临着生境退化和丧失的威胁。在此基础上对国家重点保护植物今后的保护及监测提出了对策和建议,为生物多样性研究、保护空缺分析、植被时空变化研究以及动态监测等方面的工作提供借鉴。  相似文献   

12.
<正>新疆布尔根河狸国家级自然保护区位于新疆阿勒泰地区青河县境内,东与蒙古国接壤,西至青格里河与布尔根河交汇处,地理坐标为90o27'–91o00'E,46o05'–46o15'N。地势东北高西南低,地形为河谷平原,河谷两侧为山地,山地之间是狭窄较平坦且闭塞的凹地,整个山麓平原区由东南向西北倾斜。年降水80–130 mm,年平均气温3℃左右,7月平均气温20.7℃,1月平均气温–15.8℃。布尔根河狸国家级自然保护区植被主要由河谷草地植物群  相似文献   

13.
李锐  李生才  梁娟  张伟 《蛛形学报》2010,19(2):99-103
在经过多年野外调查、采集、室内显微鉴定的基础上,本课题组将采自山西历山国家级自然保护区已定名的蜘蛛种类名录整理于下,共包括18科45属71种,其中包括2个大陆新记录种,1个山西新纪录科,9个山西新纪录属,26个山西新记录种.  相似文献   

14.
红外相机监测是了解野生动物多样性和威胁因素的重要手段。本研究采用网格法和分层抽样调查法, 在贵州赤水桫椤国家级自然保护区内选取20个监测位点布设红外相机, 对区内鸟兽物种多样性进行监测。2015年8月至2017年8月, 红外相机累计工作6,370个工作日, 共拍摄45,953张照片, 独立有效照片1,936张。准确鉴定出兽类4目8科19种, 鸟类4目11科28种, 其中, 国家II级重点保护野生动物7种。相对丰富度指数(RAI)排前五位的兽类依次是毛冠鹿(Elaphodus cephalophus)、鼬獾(Melogale moschata)、藏酋猴(Macaca thibetana)、小麂(Muntiacus reevesi)和野猪(Sus scrofa); 鸟类依次是紫啸鸫(Myophonus caeruleus)、红腹角雉(Tragopan temminckii)、灰胸竹鸡(Bambusicola thoracicus)、黑喉噪鹛(Garrulax chinensis)和棕颈钩嘴鹛(Pomatorhinus ruficollis)。物种积累曲线结果表明, 兽类稀疏化曲线在300天后趋于稳定, 表明监测取样已较充分, 而鸟类监测物种数随时间积累依旧保持增长趋势。  相似文献   

15.
Entomological records for the Island of Rhum have been brought together to form an inventory of 2158 species of insects. It is the result of intense surveys conducted in the 1960s combined with casual collecting by visiting and resident entomologists and includes documented records since 1895.
The diversity of insects recorded is, perhaps, greater than might have been anticipated in a bleak and windswept Hebridean island. Man-made habitats in the form of mixed woodland, farmland and gardens support the greatest range of species present though most of the resident insect rarities occur in coastal or upland habitats.
The island is a National Nature Reserve owned by the Nature Conservancy Council whose management policies include a large scale woodland restoration programme aimed at recreating forest formations composed of native trees and shrubs, as well as studies on the effects of red deer Cervus elaphus and other grazing animals on existing vegetation communities outwith the planting areas. This catalogue serves as a baseline by which changes resulting from these management activities, as well as cyclical population changes, can be measured.  相似文献   

16.
2017年8月至2018年8月,在甘肃祁连山国家级自然保护区内布设3个监测样区60台红外相机,累计14 999个相机日,获得野生动物独立有效照片1619张,鉴定19种哺乳动物隶属于5目9科,还记录到3种家畜.国家Ⅰ级重点保护动物3种,国家Ⅱ级重点保护动物5种.中国特有种2种.被IUCN红色名录评估为"濒危(EN)"的1...  相似文献   

17.
<正>安徽天马国家级自然保护区(31°10′–31°20′N,115°20′–115°50′E)位于皖西大别山腹地皖、鄂、豫三省交界处,由原天堂寨、马鬃岭两个省级自然保护区以及鲍家窝、窝川、九峰尖和康王寨4个国有林区组建而成,属森林生态系统类型自然保护区。该保护区处于亚热带向暖温带的过渡区,主要的植被类型有亚热带常绿阔叶林和暖温带落叶阔叶林。气候属华东湿润亚热带大陆性季风气候,年平均气温12.5℃,平均降水量为1,832.8 mm(方元平等,  相似文献   

18.
花坪保护区鸟兽物种的红外相机初步监测   总被引:3,自引:0,他引:3  
<正>广西花坪国家级自然保护区位于广西东北部,地跨临桂、龙胜两县,是南岭支脉越城岭山地南延的主要组成部分,地理位置为109°49′07″–109°58′10″E,25°28′55″–25°39′15″N,总面积151.33km2,海拔600–1,800 m。该区属中亚热带气候,年均降水量2,000–2,200 mm,年平均气温12–14℃,常出现阴湿多雨雾大的天气,林间相对湿度经常保持在85–90%。区内保存有完整的中亚热带典型常绿阔叶林和完整的植被垂直带谱,分布有我国著名的孑遗  相似文献   

19.
Liu P  Huang XF  Gu SS  Lu CH 《动物学研究》2012,33(2):170-176
2009年10月—2010年11月在江西官山国家级自然保护区对白颈长尾雉、白鹇、勺鸡和灰胸竹鸡4种雉类的生境选择进行了研究:共调查了6条样线上的388个样方,选取了与这四种雉类栖息地相关的17个生态因子进行观测和测量。结果显示,4种雉类均偏好阔叶林和针阔混交林、阳坡或半阴半阳坡的生境。Kruskal-Wallistest检验表明,4种雉类在海拔、坡度、乔木盖度、灌木盖度、灌木数量、灌木高度、草本盖度、草本种类、草本数量、落叶层盖度和水源距离11个生态因子上存在极显著差异(P<0.01),乔木种类存在显著差异(P<0.05),其余生态因子无显著差异(P>0.05)。典则判别函数图显示,4种雉类在生境选择上存在一定程度的重叠,又有比较明显的差异。逐步判别表明在区分4种雉类生境选择差异方面有一系列的生态因子发挥作用,依照贡献值的大小依次为海拔、草本数量、灌木高度、水源距离、灌木盖度、乔木盖度、坡度、落叶层盖度、灌木数量、草本盖度。由这10个变量构成的方程对4种雉类生境选择差异的正确区分率为74.7%。  相似文献   

20.
2017年4月至2019年10月,利用红外相机在四川雪宝顶国家级自然保护区开展了野生动物调查工作.共在152个位点上布设了红外相机,累积30,792个相机日,共获得独立照片6,316张.共鉴定出野生动物105种,包括27种兽类(隶属于4目13科)和78种鸟类(隶属于5目20科).其中,属于国家Ⅰ级重点保护的野生动物有7...  相似文献   

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