期刊文献+
共找到295篇文章
< 1 2 15 >
每页显示 20 50 100
悬铃木方翅网蝽:一种正在迅速扩张的城市外来入侵害虫 被引量:38
1
作者 鞠瑞亭 李博 《生物多样性》 CAS CSCD 北大核心 2010年第6期638-646,共9页
悬铃木方翅网蝽(Corythucha ciliata)是新近入侵我国城市生态系统的外来害虫,严重危害城市行道树悬铃木(Platanus spp.),自2002年该虫在湖南长沙首度报道以来,已在我国11个省(直辖市)的25个城市发生,尤其在长江流域呈现爆发态势。本文... 悬铃木方翅网蝽(Corythucha ciliata)是新近入侵我国城市生态系统的外来害虫,严重危害城市行道树悬铃木(Platanus spp.),自2002年该虫在湖南长沙首度报道以来,已在我国11个省(直辖市)的25个城市发生,尤其在长江流域呈现爆发态势。本文系统介绍了悬铃木方翅网蝽的生活史、生活习性、繁殖潜力等生物学特性,以及扩散速度与方式、影响发生的主要环境因素、种群的耐寒耐热能力等生态学特性。最后,在分析该虫的寄主及危害特点的基础上,对其控制与管理对策进行了综述,以为其管理提供参考。 展开更多
关键词 Corythucha ciliata 入侵 生物学 生态学
原文传递
七姊妹山保护区红椿种群动态与谱分析 被引量:8
2
作者 汪洋 张敏 +5 位作者 陈霞 周火明 操英南 肖创伟 梁国章 李新枝 《湖北农业科学》 2015年第22期5632-5636,共5页
为研究红椿(Toona ciliata Roem)种群动态,将林木径级代表年龄结构,分析了龄级与种群数量动态,编制了静态生命表,绘制并分析了存活曲线、死亡率曲线和种群损失度曲线,对种群进行了谱分析。结果表明,七姊妹山红椿种群衰退动态指数Vpi=32.... 为研究红椿(Toona ciliata Roem)种群动态,将林木径级代表年龄结构,分析了龄级与种群数量动态,编制了静态生命表,绘制并分析了存活曲线、死亡率曲线和种群损失度曲线,对种群进行了谱分析。结果表明,七姊妹山红椿种群衰退动态指数Vpi=32.32%,稳定动态指数Vpi′=4.039%,属于增长型稳定种群,风险敏感度较高。存活曲线接近DeeveyⅡ型,各龄级个体具有大体相等的死亡率。死亡率qx与损失率Kx均在1、4、6级出现高峰,说明不同阶段红椿生理特性、环境筛与人为干扰因素对种群的影响较大。波谱分析基波A1=0.752 8,A3出现明显小周期,表明红椿种群天然更新存在着周期性,且有小周期的多谐波叠加。 展开更多
关键词 红椿(Toona ciliata Roem) 种群动态 谱分析 七姊妹山
下载PDF
白洋淀的纤毛虫及与水质污染的关系 被引量:8
3
作者 冯建社 《重庆环境科学》 1999年第5期33-35,共3页
对白洋淀纤毛虫的种类组成、优势种进行了初步调查,同时对水质进行理化监测,共鉴定出纤毛虫48 种。根据Marsson 引出的污水生物体系法分析,白洋淀纤毛虫主要由耐有机污染的种群组成,说明白洋淀主要受有机污染。纤毛虫的种... 对白洋淀纤毛虫的种类组成、优势种进行了初步调查,同时对水质进行理化监测,共鉴定出纤毛虫48 种。根据Marsson 引出的污水生物体系法分析,白洋淀纤毛虫主要由耐有机污染的种群组成,说明白洋淀主要受有机污染。纤毛虫的种类数与水体中TN、TP、BOD5 有着密切关系。 展开更多
关键词 白洋淀 纤毛虫 有机污染 水质污染 湖泊
下载PDF
原生动物监测及预测评价污水处理厂运行状况的研究 被引量:8
4
作者 聂维明 孔秀琴 《给水排水》 CSCD 北大核心 2007年第12期50-52,共3页
在兰州雁儿湾污水处理厂采用微型生物群落监测方法——PFU法,以曝气池微型生物种群——纤毛虫类为研究对象,通过PFU监测及同期BOD5检测,发现污水处理厂曝气池纤毛虫物种丰富,以钟虫等固着缘毛目类为优势类群。纤毛虫类微型生物种数及数... 在兰州雁儿湾污水处理厂采用微型生物群落监测方法——PFU法,以曝气池微型生物种群——纤毛虫类为研究对象,通过PFU监测及同期BOD5检测,发现污水处理厂曝气池纤毛虫物种丰富,以钟虫等固着缘毛目类为优势类群。纤毛虫类微型生物种数及数量丰度随时间季节有明显的变化特性。数据显示,纤毛虫数量丰度和种数与出水BOD5有一定的线性规律,证明了纤毛虫类优势种属能够指示出水水质的发展趋势,同时预测评价污水处理厂的运行状况。 展开更多
关键词 原生动物 PFU法 纤毛虫 预测评价 污水处理厂
下载PDF
三种楝科植物的挥发物成分分析 被引量:4
5
作者 卢进 刘志韬 +2 位作者 李莉玲 温秀军 李奕震 《湖北农业科学》 2016年第2期461-464,共4页
为了探究红椿(Toona ciliata Roem.)、毛麻楝[Chukrasia tabularis var.velutina(Wall)King]和非洲桃花心木[Khaya senegalensis(Desr.)A.Juss]3种楝科植物挥发物组分,采用动态顶空采集法利用气相色谱/质谱(GC/MS)联用法分析了这3种植... 为了探究红椿(Toona ciliata Roem.)、毛麻楝[Chukrasia tabularis var.velutina(Wall)King]和非洲桃花心木[Khaya senegalensis(Desr.)A.Juss]3种楝科植物挥发物组分,采用动态顶空采集法利用气相色谱/质谱(GC/MS)联用法分析了这3种植物挥发性有机物(Volatile organic compounds,VOCs)的主要成分。结果表明,3种楝科植物挥发物组分有萜烯类、芳香烃类、醇类、醛类、烷烃类、酮类、酯类、酸类和酚类,且均以萜烯类为主,以(1R)-(+)-α蒎烯为主要成分。红椿释放22种化合物,萜烯类含量占67.41%;毛麻楝释放19种化合物,萜烯类含量占55.96%;非洲桃花心木释放21种化合物,萜烯类含量占81.27%。 展开更多
关键词 植物挥发性有机物(VOCs) 红椿(Toona ciliata Roem.) 毛麻楝[Chukrasia tabularis var.velutina(Wall)King] 非洲桃花心木[Khaya senegalensis(Desr.)A.Juss] 气相色谱/质谱(GC/MS)联用
下载PDF
Establishment of high frequency shoot regeneration system in Himalayan poplar(Populus ciliata Wall. ex Royle) from petiole explants using Thidiazuron cytokinin as plant growth regulator 被引量:4
6
作者 G. Aggarwal A. Gaur D. K. Srivastava 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第3期651-656,共6页
Populus species are important resources for industry and in scientific study on biological and agricul- tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar (Populus cil... Populus species are important resources for industry and in scientific study on biological and agricul- tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar (Populus ciliata wall. ex Royle). The effect of TDZ alone and in combi- nation with adenine and NAA was studied on the regen- eration potential of petiole explants. The explants were excised from Himalayan poplar plants grown in glass- houses. After surface sterilization the explants were cul- tured on shoot induction medium. High percentage shoot regeneration (86 %) was recorded on MS medium sup- plemented with 0.004 mg L-1 TDZ and 79.7 mg L-1 adenine. The regenerated shoots for elongation and multi- plication were transferred to MS + 0.5 mg L-1 BAP + 0.2 mg L-1 IAA + 0.3 mg L-1 GA3. Root re- generation from shoots developed in vitro was observed on MS medium supplemented with 0.10 mg L-1 IBA. Hi- malayan poplar plantlets could be produced within 2 months after acclimatization in a sterile mixture of sand and soil. We developed a high efficiency plant regeneration protocol from petiole explants of P. ciliata. 展开更多
关键词 In vitro regeneration Petiole explants Growth regulator THIDIAZURON Populus ciliata
下载PDF
凿贝才女虫形态与结构观察 被引量:4
7
作者 高燕 张涛 +1 位作者 杨红生 张晓芳 《海洋科学》 CAS CSCD 北大核心 2011年第10期103-109,共7页
应用石蜡切片和电镜技术对凿贝才女虫(Polydora ciliata)的形态结构进行了详细观察,以期为多毛类分类学积累更多资料。结果显示凿贝才女虫背刚毛、腹刚毛和疣足上的刚毛围绕身体形成一个刚毛环;第五刚节刚毛变形,形成爪状结构。体表有... 应用石蜡切片和电镜技术对凿贝才女虫(Polydora ciliata)的形态结构进行了详细观察,以期为多毛类分类学积累更多资料。结果显示凿贝才女虫背刚毛、腹刚毛和疣足上的刚毛围绕身体形成一个刚毛环;第五刚节刚毛变形,形成爪状结构。体表有大量腺细胞。身体结构相对简单,主要由表皮、肌肉层、消化系统组成。肌肉层发达,每一体节具一对疣足,疣足上生有刚毛,运动能力比较强。 展开更多
关键词 凿贝才女虫(Polydora ciliata) 形态 结构
下载PDF
九宫山红椿种群结构和空间分布格局分析 被引量:6
8
作者 张华香 汪洋 +2 位作者 冷艳芝 杨旭 尹茜 《湖北农业科学》 2017年第14期2685-2689,共5页
对九宫山保护区惟一红椿(Toona ciliata Roem.)群落设立2个样地,研究了T1和T2样地种群空间分布格局。通过龄级划分研究种群年龄结构和动态量化分析,以探讨不同样地红椿种群空间结构与分布格局的成因。结果显示,2个样地的种群分布格局在1... 对九宫山保护区惟一红椿(Toona ciliata Roem.)群落设立2个样地,研究了T1和T2样地种群空间分布格局。通过龄级划分研究种群年龄结构和动态量化分析,以探讨不同样地红椿种群空间结构与分布格局的成因。结果显示,2个样地的种群分布格局在16、25、50、100 m^2时,均为泊松分布;取样面积越大,Lloyd平均拥挤度(m*)和丛生指数(I)越大;T2样地的Lloyd平均拥挤度(m*)和丛生指数(I)值均高于T1样地。T1和T2样地Ⅰ龄级数量分别占总量的41.86%和48.18%,Ⅳ、Ⅴ龄级环境筛与竞争作用加强。2个样地种群动态指数变化差异较大,T1样地为10个龄级,V_Ⅳ、V_Ⅴ、V_Ⅵ为波动;T2样地12个龄级,V_Ⅳ、V_Ⅴ、V_Ⅸ、V_Ⅹ为波动。2个样地种群V_(pi1)=40.83%,V′_(pi1)=2.041,V_(pi2)=49.72%,V′_(pi2)=4.144,均属于增长性种群,天然更新较好,但种群老龄化趋势明显。因此,加强森林抚育,人为制造林窗,将更有利于红椿种群的更新和稳定发展。 展开更多
关键词 红椿(Toona ciliata Roem.) 种群结构 空间分布格局 九宫山
下载PDF
恩施不同红椿群落α多样性与种群分布格局相关分析 被引量:3
9
作者 江雄波 张敏 +2 位作者 汪洋 刘芳芳 陈政 《湖北农业科学》 2016年第15期3923-3928,共6页
为研究恩施地区红椿(Toona ciliata Roem.)群落α多样性与红椿种群空间分布格局的相关性,采用样方法对恩施4个不同红椿天然群落样地进行调查。对群落α多样性指数与种群空间分布格局相关性分析表明,群落草本与灌木层α多样性指数相关性... 为研究恩施地区红椿(Toona ciliata Roem.)群落α多样性与红椿种群空间分布格局的相关性,采用样方法对恩施4个不同红椿天然群落样地进行调查。对群落α多样性指数与种群空间分布格局相关性分析表明,群落草本与灌木层α多样性指数相关性较低;草本与乔木层α多样性指数之间存在较强负相关;灌木与乔木层α多样性表现为显著或极显著正相关。红椿群落群层间α多样性与种群分布格局相关性表明,群落草本层的多样性与红椿种群分布格局间相关性较低;种群分布格局与灌木和乔木α多样性呈高度负相关。研究表明,群层间α多样性存在较为不同的相关性,可能是由于竞争中不平等的资源分配,影响红椿群落物种的演替方向;红椿群落乔灌层的α多样性指数越高,对红椿种群的分布格局影响越大,促使红椿种群分布格局趋于泊松分布。 展开更多
关键词 红椿(Toona ciliata Roem.) Α多样性 种群格局 相关分析 恩施
下载PDF
红椿天然种群分布格局的检验方法 被引量:3
10
作者 汪洋 汪林波 +3 位作者 余春前 张小勇 张琴琴 陈松 《湖北农业科学》 2016年第13期3383-3386,共4页
为研究濒危物种红椿(Toona ciliata Roem.)的种群分布格局,在谷城南河流域对发现的仅有两个红椿种群(T1、T2)以相邻格子法设置5 m×5 m、3 m×3 m的样方,精确到1 m格子。通过χ2验、Cx的t检验、Morisita I_δ的F检验,对种... 为研究濒危物种红椿(Toona ciliata Roem.)的种群分布格局,在谷城南河流域对发现的仅有两个红椿种群(T1、T2)以相邻格子法设置5 m×5 m、3 m×3 m的样方,精确到1 m格子。通过χ2验、Cx的t检验、Morisita I_δ的F检验,对种群分布格局进行判断是否符合泊松分布。结果表明,T1种群在5 m×5 m、3 m×3 m样方尺度下,C_x和I_δ均为泊松分布,5 m×5 m尺度χ2验为集群分布,3 m×3 m尺度为泊松分布;干扰种群T2种群密度较大,3种检验均为集群分布。因此,分布格局满足χ2验的泊松分布,样方设置应注重尺度和数量;df越大,理论值与观测值更可能越接近正态分布,种群分布格局的检验更加真实可信。 展开更多
关键词 红椿(Toona ciliata Roem.) 天然种群 分布格局 检验方法
下载PDF
Discovery and preclinical development of ⅢM-160, a Bergenia ciliatabased anti-inflammatory and anti-arthritic botanical drug candidate 被引量:3
11
作者 Sandip B.Bharate Vikas Kumar +8 位作者 Sonali S.Bharate Bikarma Singh Gurdarshan Singh Amarinder Singh Mehak Gupta Deepika Singh Ajay Kumar Surjeet Singh Ram A.Vishwakarma 《Journal of Integrative Medicine》 SCIE CAS CSCD 2019年第3期192-204,共13页
Objective: Bergenia ciliata(Haw.) Sternb. is used in the Indian traditional system of medicine to treat various ailments including rheumatism and to heal wounds. The objective of the present study was to perform a pre... Objective: Bergenia ciliata(Haw.) Sternb. is used in the Indian traditional system of medicine to treat various ailments including rheumatism and to heal wounds. The objective of the present study was to perform a preclinical characterization of the B. ciliata-based botanical extract IIIM-160.Methods: ⅢM-160 was chemically standardized and analyzed for heavy metal content, aflatoxins,pesticides and microbial load. The in vitro and in vivo efficacies were determined in suitable models of inflammation, arthritis and nociception. An acute oral toxicity study was performed in Swiss albino mice.A suitable oral formulation was developed and characterized.Results: Bergenin was found to be the major component(9.1% w/w) of ⅢM-160. The botanical lead displayed inhibition of lipopolysaccharide-induced production of proinflammatory cytokines in THP-1 cells, with selectivity toward interleukin-6(IL-6) and had an excellent safety-window. It showed anti-inflammatory, anti-arthritic and antinociceptive activity in animal models and was not toxic at oral doses up to 2 g/kg in Swiss-albino mice. The gastroretentive, sustained-release capsule formulation showed sustained-release of the bergenin over the period of 24 h, resulting in improved plasma-exposure of bergenin in Sprague–Dawley rats.Conclusion: The dual-activity of IL-6 inhibition and antinociception marks the suitability of ⅢM-160 for treating rheumatoid arthritis. This study will serve as the benchmark for further research on this botanical formulation. 展开更多
关键词 BOTANICAL PRECLINICAL candidate UIM-160 Bergenia ciliata Arthritis GASTRORETENTIVE sustained release formulation BERGENIN
原文传递
中国土壤原生动物纤毛亚门Ciliophora 2新记录 被引量:1
12
作者 宋碧玉 《武汉水利电力大学学报》 CSCD 1993年第6期718-720,共3页
报道了土壤原生动物纤毛亚门Ciliophora2个中国新记录种;伊丽肾形虫Colpoda elliotti Bradburg et Outka 1967和快速肾形虫Colpoda fastigata Kahl 1931,并予以描述。
关键词 土壤原生动物 纤毛纲 新记录
原文传递
红椿嫩枝扦插繁殖技术 被引量:1
13
作者 陈琴 陈仕昌 +4 位作者 黄开勇 程琳 梁瑞龙 蓝肖 姜英 《林业科技通讯》 2023年第4期72-76,共5页
以红椿(Toona ciliata)为研究材料,采用L9(34)正交试验设计开展控制试验,研究母树类型、插穗长度、GGR6浓度和扦插基质对红椿嫩枝扦插效果的影响,为红椿扦插繁殖提供科学依据。结果表明:母树类型对插穗保存率有极显著影响,对生根率有显... 以红椿(Toona ciliata)为研究材料,采用L9(34)正交试验设计开展控制试验,研究母树类型、插穗长度、GGR6浓度和扦插基质对红椿嫩枝扦插效果的影响,为红椿扦插繁殖提供科学依据。结果表明:母树类型对插穗保存率有极显著影响,对生根率有显著影响,1年生截干母树的插穗保存率和生根率最高,其次为2年生截干母树,最后为3年生幼树;GGR6浓度对插穗生根率及根系发育指标有极显著影响,500mg/L和1000mg/L处理极显著优于100mg/L处理,500mg/L和1000mg/L处理二者之间差异不显著。插穗长度和扦插基质对各指标的影响不显著。红椿嫩枝扦插的最佳处理水平组合为:从2年生截顶母树采集插穗,将插穗修剪成10cm长度,采用由浓度为1000mg/LGGR6溶液制备而成的生根泥浆速蘸插穗1min,并将插穗置于红心土中培养,扦插70d后插穗保存率为100.00%,生根率为94.44%。 展开更多
关键词 红椿 Toona ciliata 无性繁殖 扦插 母树类型 生根率
原文传递
Study on the Difference between Volatile Constituents of the Different Parts from <i>Elsholtzia ciliata</i>by SHS-GC-MS 被引量:2
14
作者 Xiaoming Wang Lili Gong Haiqiang Jiang 《American Journal of Analytical Chemistry》 2017年第10期625-635,共11页
In this study, the comparison of Elsholtzia ciliata volatile compounds from the stem (with leaf) and flower was acquired. The volatile compounds of these two parts from Elsholtzia ciliata aerial parts were respectivel... In this study, the comparison of Elsholtzia ciliata volatile compounds from the stem (with leaf) and flower was acquired. The volatile compounds of these two parts from Elsholtzia ciliata aerial parts were respectively analyzed by a rapid and convenient static headspace injection technique coupled with gas chromatography-mass spectrometry and the relative contents of each constituent between the two different parts were determined by peak area normalization. 61 compounds were identified in the stem (with leaf) and flower, among which 39 components simultaneously exist. 47 and 53 compounds were separated and identified in the volatile compounds from the different parts of Elsholtzia ciliata, respectively. There were differences among some volatile constituents of the two parts, but the main constituents were all Elsholtzia ketone, caryophyllene, 3-octanol and Dehydroelsholtzia ketone. The most abundant components in the stem (with leaf) included Elsholtzia ketone (84.20%), caryophyllene (4.3%) and 3-octanol (3.11%), while Elsholtzia ketone (88.03%), caryophyllene (3.33%) and 3-octanol (1.53%) were the main components in the flower. 8 single constituents were identified in the stem (with leaf) volatiles including 3-heptanone and linalool, while 14 constituents only including 2-methylbutanoic acid and Perillene have been found in the flower volatiles. Elsholtzia ketone was the main compound, and its concentration was significantly higher than other substances (>80% of the total oils in Elsholtzia ciliata). The study provided an important scientific base for the further utilization of Elsholtzia ciliata resources and may be helpful for systematically understanding the constituents of volatile compounds of Elsholtzia ciliata. 展开更多
关键词 ELSHOLTZIA ciliata VOLATILE Constituents Static HEADSPACE Injection Technique Gas Chromatography-Mass SPECTROMETRY
下载PDF
Research on Genetic Physiological Ecology of Precious Species: Toona ciliata and Toona ciliata var. pubescens 被引量:2
15
作者 赵伯金 甄爱国 +2 位作者 贺润轩 程德华 汪洋 《Agricultural Science & Technology》 CAS 2015年第5期997-1001,共5页
Toona ciliata and Toona ciliata var. pubescens are timber species of national second-class protective plants. In China, Toona ciliata and Toona ciliata var.pubescens distribute sporadically with small population size ... Toona ciliata and Toona ciliata var. pubescens are timber species of national second-class protective plants. In China, Toona ciliata and Toona ciliata var.pubescens distribute sporadically with small population size but with great development potential. Plus selection on phenotype of Toona ciliata and Toona ciliata var.pubescens, molecular genetic marker of Toona ciliata var. pubescens, research progress in physiology and ecology of Toona ciliata and Toona ciliata var.pubescens were summarized in this paper. Suggestions and prospect forecast were proposed for relative research and utilization. 展开更多
关键词 Toona ciliata Toona ciliata var. pubescens HEREDITY PHYSIOLOGY ECOLOGY
下载PDF
马鹿河红椿群落α多样性与种群格局分析 被引量:2
16
作者 冷艳芝 汪洋 +5 位作者 陈益娴 张敏 宋菲 付翠林 谢昌兵 白琳 《湖北农业科学》 2016年第9期2265-2268,共4页
选择恩施马鹿河完整天然红椿(Toona ciliata)群落设置400 m2样地,建立了16个5 m×5 m样方,采用相邻格子法进行调查,研究群落α多样性和红椿种群格局。结果表明,群落α多样性指数表现为灌木﹥草本﹥乔木,各林层α多样性呈显著正相关... 选择恩施马鹿河完整天然红椿(Toona ciliata)群落设置400 m2样地,建立了16个5 m×5 m样方,采用相邻格子法进行调查,研究群落α多样性和红椿种群格局。结果表明,群落α多样性指数表现为灌木﹥草本﹥乔木,各林层α多样性呈显著正相关。25、50、100 m2取样,7个种群空间分布数学模型表明,红椿的天然种群以泊松分布为主要特征,100 m2尺度上为均匀分布。Iwao回归模型:m*=-2.412+1.868 x,和上述7个模型结论一致。保护红椿群落物种α多样性有利于促进红椿种群稳定;红椿天然种群以泊松分布为基本分布特征。 展开更多
关键词 红椿(Toona ciliata) 群落 种群 Α多样性 种群格局
下载PDF
Effects of water stress on growth phenology photosynthesis and leaf water potential in Stipagrostis ciliata(Desf.)De Winter in North Africa
17
作者 Lobna MNIF FAKHFAKH Mohamed CHAIEB 《Journal of Arid Land》 SCIE CSCD 2023年第1期77-90,共14页
Stipagrostis ciliata(Desf.)De Winter is a pastoral C4 grass grown in arid regions.This research work focused on assessing the growth of S.ciliata accessions derived from two different climate regions(a wet arid region... Stipagrostis ciliata(Desf.)De Winter is a pastoral C4 grass grown in arid regions.This research work focused on assessing the growth of S.ciliata accessions derived from two different climate regions(a wet arid region in the Bou Hedma National Park in the central and southern part of Tunisia(coded as WA),and a dry arid region from the Matmata Mountain in the south of Tunisia(coded as DA))under water stress conditions.Specifically,the study aimed to investigate the phenological and physiological responses of potted S.ciliata seedlings under different water treatments:T_(1)(200 mm/a),T_(2)(150 mm/a),T_(3)(100 mm/a)and T_(4)(50 mm/a).Growth phenology,net photosynthesis(Pn),stomatal conductance(gs),midday leaf water potential(Ψmd),predawn leaf water potential(Ψpd),soil water content(SWC)and soil water potential(Ψs)were observed during the water stress cycle(from December 2016 to November 2017).The obtained results showed that the highest growth potential of the two accessions(WA and DA)was recorded under treatment T_(1).The two accessions responded differently and significantly to water stress.Photosynthetic parameters,such as Pn and gs,decreased sharply under treatments T_(2),T_(3)and T_(4)compared to treatment T_(1).The higher water stress increased the R/S ratio(the ratio of root dry biomass to shoot dry biomass),with values of 1.29 and 2.74 under treatment T_(4)for accessions WA and DA,respectively.Principal component analysis(PCA)was applied,and the separation of S.ciliata accessions on the first two axes of PCA(PC1 and PC2)suggested that accession DA was detected in the negative extremity of PC1 and PC2 under treatments T_(1)and T_(2).This accession was characterized by a high number of spikes.For treatments T_(3)and T_(4),both accessions were detected in the negative extremity of PC1 and PC2.They were characterized by a high root dry biomass.Therefore,S.ciliata accessions responded to water stress by displaying significant changes in their behaviours.Accession WA from the Bou Hedma National Park(wet arid re 展开更多
关键词 Stipagrostis ciliata drought stress water deficit gas exchange arid regions Tunisia
下载PDF
Species Abundance Distribution Patterns of a Toona ciliata Community in Xingdoushan Nature Reserve 被引量:4
18
作者 WANG Yang ZHU Shengjie +3 位作者 LI Jie HE Xiuling JIANG Xiongbo ZHANG Min 《Journal of Resources and Ecology》 CSCD 2019年第5期494-503,共10页
With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,... With the goal of model fitting species abundance distribution patterns of the tree,shrub and herb layers of the natural Toona ciliata community in Xingdoushan Nature Reserve,Enshi Autonomous Prefecture,Hubei Province,we used the data collected from the field survey and employed different ecological niche models.The models tested were the broken stick model(BSM),the overlapping niche model(ONM)and the niche preemption model(NPM),as well as three statistic models,the log-series distribution model(LSD),the log-normal distribution model(LND)and the Weibull distribution model(WDM).To determine the fitted model most suitable to each layer,the fitting effects were judged by criteria of the lowest value of Akaike Information Criterion(AIC),Chi-square and the K-S values with no significant difference(P>0.05)between the theoretical predictions and observed species abundance distribution values.The result showed:(1)The fitting suitability and goodness of fit of the tree,shrub and herb layers by using the three ecological niche models were ranked as:NPM>BSM>ONM.Of the three statistical models,by accepting the fitting results of the three layers,WDM was the best fitting model,followed by LND.By rejecting the fitting tests of the herb layer,LSD had the worst fitting effect.The goodness of the statistical models was ranked as:WDM>LND>LSD.In general,the statistical models had better fitting results than the ecological models.(2)T.ciliata was the dominant species of the tree layer.The species richness and diversity of the herb layer were much higher than those of either the tree layer or the shrub layer.The species richness and diversity of the shrub layer were slightly higher than those of the tree layer.The community evenness accorded to the following order:herb>shrub>tree.Considering the fitting results of the different layers,different ecological niche models or statistical models with optimal goodness of fit and ecological significance can be given priority to in studying the species abundance distribution patterns of T.cili 展开更多
关键词 Toona ciliata community tree-shrub-herb layer niche model statistical model species abundance distribution pattern fitting model
原文传递
Species abundance distribution models of Toona ciliata communities in Hubei Province,China 被引量:4
19
作者 Yang Wang Huoming Zhou +2 位作者 Jingyong Cai Congwen Song Linzhao Shi 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期103-117,共15页
The study of plant species abundance distribution(SAD)in natural communities is of considerable importance to understand the processes and ecological rules of community assembly.With the distribution of tree,shrub and... The study of plant species abundance distribution(SAD)in natural communities is of considerable importance to understand the processes and ecological rules of community assembly.With the distribution of tree,shrub and herb layers of eight natural communities of Toona ciliata as research targets,three diff erent ecological niche models were used:broken stick model,overlapping niche model and niche preemption model,as well as three statistical models:log-series distribution model,log-normal distribution model and Weibull distribution model,to fi t SAD of the diff erent vegetation layers based on data collected.Goodness-of-fi t was compared with Chi square test,Kolmogorov–Smirnov(K–S)test and Akaike Information Criterion(AIC).The results show:(1)based on the criteria of the lowest AIC value,Chi square value and K–S value with no signifi cant diff erence(p>0.05)between theoretic and observed SADs.The suitability and goodness-of-fi t of the broken stick model was the best of three ecological niche models.The log-series distribution model did not accept the fi tted results of most vegetation layers and had the lowest goodness-of-fi t.The Weibull distribution model had the best goodness-of-fi t for SADs.Overall,the statistical SADs performed better than the ecological ones.(2)T.ciliata was the dominant species in all the communities;species richness and diversity of herbs were the highest of the vegetation layers,while the diversities of the tree layers were slightly higher than the shrub layers;there were fewer common species and more rare species in the eight communities.The herb layers had the highest community evenness,followed by the shrub and the tree layers.Due to the complexity and habitat diversity of the diff erent T.ciliata communities,comprehensive analyses of a variety of SADs and tests for optimal models together with management,are practical steps to enhance understanding of ecological processes and mechanisms of T.ciliata communities,to detect disturbances,and to facilitate biodiversity and species 展开更多
关键词 Toona ciliata community Tree-shrubherb layers Niche models Statistical models Species abundance distribution(SAD) Model fi t
下载PDF
Study on Cutting Propagation of Toona ciliata Clones 被引量:4
20
作者 吴际友 程勇 +5 位作者 吴其军 陈明皋 李艳 黄明军 王旭军 刘球 《Agricultural Science & Technology》 CAS 2014年第11期1844-1846,共3页
Cutting propagation rhizogenesis of Toona ciliata clone cutting orchard were studied, and the results were as fol ows: Rooting type included both cal us rooting and cortex rooting. About 17 in 22 of clones were domin... Cutting propagation rhizogenesis of Toona ciliata clone cutting orchard were studied, and the results were as fol ows: Rooting type included both cal us rooting and cortex rooting. About 17 in 22 of clones were dominated by cortex rooting, accounting for the 77% of clones. There were 5 clones which occurred with both cal us rooting and cortex rooting during rooting process. The rooting efficiency index (REI) showed a positive correlation with the rooting rate. Under natural tem-perature condition, keeping moisture and shading, we found that the highest survival rate occurred in early June, September, and October. 展开更多
关键词 Toona ciliata clones Cutting propagation Rooting rate
下载PDF
上一页 1 2 15 下一页 到第
使用帮助 返回顶部