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61.
Rhinopithecus roxellana’s habitat condition is directly related to its long-term survival and reproduction. Research, with large-scale, on R. roxellana’s habitat selection of seasonal changes is conducive to the protection and construction of its habitat, and it is essential protecting the rare species. Our research is based on the results of previous studies in biological and behavioral ecological field. With the support of GIS and RS technology, we conducted a lot of field investigations. In addition, we also took R. roxellana’s selection bias of seven kinds of ecological factors into consideration. Through the above efforts, we got a selection intensity distribution layer about R. roxellana’s habitat selection of seasonal changes. Our study shows that in spring, the area of weak intensity is 1507.96 hm2 while less weak area is 33868.72 hm2. The strong intensity area is 266 hm2 while the less strong area is 36818.84 hm2.
In summer, the area of weak intensity is 4683.4 hm2 while less weak area is 28392.4 hm2. The strong intensity area is 4078.52 hm2 while the less strong area is 35307.2 hm2.
In autumn, the area of weak intensity is 1972.08 hm2 while less weak area is 33254.72 hm2. The strong intensity area is 1516.84 hm2 while the less strong area is 35717.88 hm2.
In winter, the area of weak intensity is 542.76 hm2 while less weak area is 28230.84 hm2. The strong intensity area is 392.44 hm2 while the less strong area is 43295.48 hm2.
The results show that the most forestry areas of the Shennongjia Mt. lie in strong intensity area and these areas provides optimal habitat for the Snub-nosed Monkey.
The distribution layer analyses show that eastern part of the Shennongjia area is coincidence with the current natural distribution of the Snub-nosed Monkey, whereas north-western, south-western and southern part of the area is located in the weak intensity areas and is unfit for the Snub-nosed Monkey. In the central part, the strong intensity areas are fragmented by the highways and no Snub-nosed Monkey is found in this highly disturbed area. However, it is probably a potential habitat for the Snub-nosed Monkey.
Survival and reproduction of the Snub-nosed Monkey was ensured by large and continuous habitat in the eastern part of the Shennongjia Mt. Much effort is needed to intensify the connection of the fragmented central area of the Shennongjia Mt.  相似文献   
62.
1983年7月至9月期间,刘祖尧和金根桃二位同志在鄂西兴山县大神农架地区采集,从其中21个点共采到原尾虫140头,逐一进行鉴定后,共计有16种,分隶5个科,其中有3个新种和1个新记录,现列名录如下:  相似文献   
63.
湖北省神农架林区野猪分布与传播非洲猪瘟风险分析   总被引:1,自引:0,他引:1  
野猪是非洲猪瘟(ASF)传播的重要媒介,神农架林区野猪种群数量高、分布广,调查野猪分布对ASF防控有着重要意义.本研究首先通过布设红外相机117台、样线287条调查神农架林区野猪实体和痕迹位点后,应用最大熵模型预测林区野猪分布,再根据野猪、居民区、交通要道的空间分布数据,应用核密度估计法分析神农架林区各地野猪传播ASF...  相似文献   
64.
川金丝猴(Rhinopithecus roxellana)是我国特有珍稀濒危物种,了解其种群遗传结构和关键影响因素,对该物种的保护具有重要意义。以我国分布最东端的湖北神农架川金丝猴种群为研究对象,基于非损伤性DNA技术和微卫星DNA遗传标记等分子生物学方法及景观遗传参数,探讨了神农架川金丝猴的遗传多样性和遗传结构,旨在为川金丝猴的研究及川金丝猴种群的可持续发展提供理论基础。利用12个多态性微卫星位点,在455份川金丝猴粪便样品中,共检测到62个微卫星等位基因;共鉴定出316个不同川金丝猴个体;种群的平均期望杂合度、平均观察杂合度和多态性信息含量分别为0.626、0.559和0.650;群体间的Nei's遗传距离为0.046—0.139,分化系数为0.015—0.046。结果表明与其他地区川金丝猴种群相比,神农架川金丝猴种群具有较低的遗传多样性水平,种群内部存在遗传分化趋势;结合景观参数分析表明地理距离不是影响神农架川金丝猴群体间遗传距离的主要因素,而生境中的灌丛和草地以及人类活动干扰可能是影响川金丝猴遗传交流的主要因素。  相似文献   
65.
采用植物社会学调查方法,对神农架国家级自然保护区川金丝猴栖息地植物群落进行了调查,并对127个植物样方调查资料进行了聚类分析。综合数量分类及植物社会学的分类标准,将神农架川金丝猴栖息地植被划分为13个群丛和4个群落;分析了各群丛的结构特征、地理分布特征(海拔、地形等)以及不同群丛的植物组成和食源植物状况,同时对各群丛乔木层的胸径等级和高度进行了分析。结果表明:群丛Ⅰ(华山松-金佛山箬竹-湖北大戟)、群丛Ⅵ(巴山冷杉+红桦-箭竹+兴山五味子-抱茎风毛菊)、群丛Ⅸ(华山松-鄂西绣线菊-中日金星蕨)以及群丛Ⅻ(巴山冷杉+华山松-鞘柄菝葜+鄂西绣线菊-中日金星蕨)4个群丛所含物种数最多,其中群丛Ⅰ、Ⅵ、Ⅸ所含食源植物种数也最多;群丛Ⅳ(红桦-湖北花楸-离舌橐吾)胸径大于30 cm的树木所占比例及乔木层平均高度均最大;这5个群丛是神农架国家级自然保护区川金丝猴栖息地的主要植被类型。该研究可为神农架国家级自然保护区川金丝猴栖息地的植被保护与恢复提供重要参考。  相似文献   
66.
Aims: It is important to study the effects of land use change and reduced precipitation on greenhouse gas fluxes (CO2, CH4 and N2O) of forest soils. Methods: The fluxes of CO2, CH4 and N2O and their responses to environmental factors of primary forest soil, secondary forest soil and artificial forest soil under a reduced precipitation regime were explored using the static chamber and gas chromatography methods during the period from January to December in 2014. Important findings: Results indicate that CH4 uptake of primary forest soil ((-44.43 ± 8.73) μg C·m-2·h-1) was significantly higher than that of the secondary forest soil ((-21.64 ± 4.86) μg C·m-2·h-1) and the artificial forest soil ((-10.52 ± 2.11) μg C·m-2·h-1). CH4 uptake of the secondary forest soil ((-21.64 ± 4.86) μg C·m-2·h-1) was significantly higher than that of the artificial forest ((-10.52 ± 2.11) μg C·m-2·h-1). CO2 emissions of the artificial forest soil ((106.53 ± 19.33) μg C·m-2·h-1) were significantly higher than that of the primary forest soil ((49.50 ± 8.16) μg C·m-2·h-1) and the secondary forest soil ((63.50 ± 5.35) μg C·m-2·h-1) (p < 0.01). N2O emissions of the secondary forest soil ((1.91 ± 1.22) ug N·m-2·h-1) were higher than that of the primary forest soil ((1.40 ± 0.28) μg N·m-2·h-1) and the artificial forest soil ((1.01 ± 0.86) μg N·m-2·h-1). Reduced precipitation (-50%) had a significant inhibitory effect on CH4 uptake of the artificial forest soil, while it enhanced CO2 emissions of the primary forest soil and the secondary forest soil. Reduced precipitation had a significant inhibitory effect on CO2 emissions of the artificial forest soil and N2O emissions of the secondary forest (p < 0.01). Reduced precipitation promotes N2O emissions of the primary forest soil and the artificial forest soil. CH4 uptake of the primary forest and the secondary forest soil increased significantly with the increase of soil temperature under natural and reduced precipitation. CO2 and N2O emission fluxes of the primary forest soil, secondary forest soil and artificial forest soil were positively correlated with soil temperature (p < 0.05). Soil moisture inhibited CH4 uptake of the secondary forest soil and the artificial forest soil (p < 0.05). CO2 emissions of the primary forest soil were significantly positively correlated with soil moisture (p < 0.05). N2O emissions of primary forest soil and secondary forest soil were significantly correlated with the nitrate nitrogen content (p < 0.05). It was implied that reduced precipitation and land use change would have significant effects on greenhouse gas emissions of subtropical forest soils.  相似文献   
67.
神农架生物圈保护区植物多样性及其保护现状的研究   总被引:8,自引:1,他引:7  
对神农架生物圈保持区森林生态系统多样性、植物物种多样性、植物遗传多样性及其保护现状作了较斩研究,结果如下:1.神农架生物圈保护区海拔差异大,生态环境相当复杂,植被垂直分布差异明显。根据植被现状,其自然植被可划分为3个植被带,海拔420-1800m为常绿、落叶阔叶混交林带;海拔1800-2600m为温性针叶和落叶阔叶林带;海拔2600-3105.4m为寒性常绿针叶林带。  相似文献   
68.
神农架维管植物区系初步研究   总被引:28,自引:9,他引:19  
本文为神农架维管植物区系的初步研究结果,扼要报道了本区系现知的2638种(包括种下等级),分隶193科850属;粗略分析了850属的分布区类型,表明本区系以温带分布特别是北温带分布为主要成份的性质;介绍了本区系一些主要的古老属种,世界单种属47属,在中国为单种属的有33属,分布于该地区的中国特有属43属及中国列入珍稀保护植物49种。通过对木本植物的统计(有99科290属1103种,其中乔木属128属),显示出该地区是中国北温带木本植物,特别是乔木属种最丰富的地区之一。  相似文献   
69.
中国神农架地区的植被制图及植物群落物种多样性   总被引:3,自引:0,他引:3  
在野外调查、资料搜集的基础上 ,辅以全球定位系统 (GPS)、GIS软件及 TM影像数据 ,绘制了该地区 1∶ 2 0万的植被类型图。制图结果表明 :1)制图区总面积 3476 .6 7km2 ,共计 5 0 4个斑块。 2 )神农架地区林地面积 2 ,6 0 7.4 5 km2 ,占该地区总面积的 75 % ;山地灌丛及亚高山灌丛总面积 35 8.6 2 km2 ,占总面积的 10 .3% ;草甸面积 15 6 .84 km2 ,占 4 .5 1%。 3)自然植被划分为8个植被型 ,4 6个群系以及农田 (居民点 )和茶园两种农业土地利用类型。其中针叶、落叶阔叶混交林面积最大 ,为 90 8km2 ,占总面积的 37.88%。 4 )对神农架地区 8个植被型中的 4 6个群系进行的群落物种 Shannon- Wiener多样性指数 (H′)及 Pielou均匀度指数 (J)的测定结果表明 ,1各群落物种多样性总趋势是 :灌木层 >草本层 >乔木层 (个别群落除外 ) 2与天然林相比 ,人工林群落内各层次结构相对简单 ,物种多样性较低。3针叶林 (7个群系 )和针阔叶混交林 (6个群系 )中 ,低海拔人工林群落各层次及高海拔天然林乔木层结构简单 ,伴生种类较少 ,物种多样性低。高海拔天然林群落灌木层和草本层物种多样性相对高 ,H′值一般在 1.2~ 2之间 ,J值在 0 .5~ 1之间。草本层物种多样性变化明显 ,低海拔区域较低。4分布于低海拔峡谷地带的常绿  相似文献   
70.
应用样方调查法,分析了湖北神农架自然保护区川金丝猴栖息地植被乔木层物种多样性和群落结构随海拔梯度的变化。结果如下:(1)调查样方160个,总面积64000m^2,共记录木本植物37科123属289种,其中乔木25科90属198种,灌木7科29属84种,木质藤本5科4属7种。优势科主要有蔷薇科、忍冬科、樟科、壳斗科和杜鹃花科等。(2)根据不同海拔乔木层物种组成的差异,该区植被类型可分为落阔叶林(1900~2100m)、针阔叶混交林(2200~2400m)和暗针叶林(2500~2600m)3种。(3)随着海拔升高,多样性指数(Shannon—Wie—ner指数)在3种植被类型中旱下降趋势;均匀度指数(Pielou指数)在针阔叶混交林和暗针叶林中呈下降趋势,在落叶阔叶林中变化不明显。(4)随着海拔升高,各乔木层所占比例,乔木l层(〉20m)逐渐减小,乔木Ⅱ层(10~20m)无明显变化,乔木Ⅲ层(〈10m)呈上升趋势。(5)以树高替代年龄,分析了9种优势乔木村种的种群年龄结构,结果表明该区植被的乔木层呈现稳定增长趋势。  相似文献   
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