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1.
华南阔叶树种幼苗叶片的养分特征   总被引:6,自引:0,他引:6  
研究了阔叶树种幼苗山杜英、红锥、海南红豆、火力楠、红花油茶、枫香、黎蒴、米老排和樟树的N、P、K浓度和单位叶面积含量。结果表明,海南红豆、黎蒴和樟树的N、P、K浓度较高,而红花油茶、黎蒴和樟树的单位叶面积N、P、K含量较高,9种树种的上部和下部叶片的平均养分浓度分别为N16.67和17.09g·kg^-1,P1.29和0.84g·kg^-1,K11.77和6.65g·kg^-1,平均养分含量分别为N0.871和1.069g·m^-2,P0.065和0.052g·m^-2,K0.608和0.426g·m^-2,各树种上部叶片的P和K浓度和含量大于下部叶片,从养分含量的角度考虑,红花油茶与其他8种树种混交,红锥或米老排与山杜英、枫香、海南红豆、黎蒴、樟树混交,火力楠与黎蒴、樟树混交是合理的。  相似文献   

2.
一、螺旋藻富含矿物质、维生素、蛋白质、必需氨基酸和必需脂肪酸,特别是α-亚麻酸。也是β-胡萝卜素的良好来源。螺旋藻中的铁特别容易被人体吸收。最近的研究证明,螺旋藻可有效地改善免疫功能,降低血清中的胆固醇水平,改善肝功能。经常食用螺旋藻还可增加胃肠道中的有益细菌。二、小球藻富含叶绿素、蛋白质和矿物质(包括磷、钾、镁、硫、铁、钙、铜、锌、碘、钻和其他微量元素、。还含有卜胡萝卜素,以及维生素C、E、K、B1、B2、B6、和B12,烟酸,泛酸,叶酸,生物素,胆碱和肌醇。营养价值很高。可调节胆固醇,有强烈的抗肿瘤和…  相似文献   

3.
中国葡萄属植物形态学聚类分组研究   总被引:3,自引:1,他引:2       下载免费PDF全文
对《中国葡萄志》描述的38个中国葡萄属野生种和1个栽培种,按照《葡萄种质资源描述规范和数据标准》的要求,对18个描述符用代码数量化并进行聚类分析,根据形态特征的相似程度,将我国葡萄属野生种和欧亚种划分为8个组和5个亚组。第1组包含毛葡萄、腺枝葡萄、龙泉葡萄、美丽葡萄和庐山葡萄,第2组包含麦黄葡萄和小叶葡萄,第3组包含5个亚组21个种类,其中亚组1包含山葡萄、陕西葡萄、浙江蘡薁、蘡薁和湖北葡萄,亚组2包含绵毛葡萄和勐海葡萄,亚组3包含小果葡萄、云南葡萄和葛藟葡萄,亚组4包含毛脉葡萄、华东葡萄、武汉葡萄和井冈葡萄,亚组5包含刺葡萄、秋葡萄、桦叶葡萄、网脉葡萄、蒙自葡萄、凤庆葡萄和河口葡萄,第4组仅包含欧洲葡萄,第5组包含温州葡萄、红叶葡萄、复叶葡萄、乳源葡萄和狭叶葡萄,第6组包含东南葡萄、罗城葡萄和闽赣葡萄,第7组仅包含菱叶葡萄,第8组仅包含鸡足葡萄一个种。  相似文献   

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湖北省纽荷尔脐橙果实品质状况的研究   总被引:2,自引:0,他引:2  
以纽荷尔脐橙为试材,分析了湖北省13个产地果实的常规品质和果皮色差值。结果显示,不同产地纽荷尔脐橙果实品质差异明显。系统聚类结果表明,秭归县、巴东县和兴山县的常规品质聚为第一类,长阳县、郧县、公安县、枝江市和宜都市聚为第二类,而丹江口市、阳新县、通城县、天门市和京山县聚为第三类;就果皮色差值来看,长阳县、郧县、兴山县和宜都市聚为第一类,巴东县、京山县、枝江市、丹江口市、阳新县、公安县、秭归县聚为第二类,天门市和通城县聚为第三类。综合分析常规品质和果皮色差值可以看出,三峡库区的兴山县、秭归县、巴东县纽荷尔脐橙综合品质最好,邻近三峡库区的长阳县、宜都市、枝江市,丹江库区的郧县和卷桥库区的公安县次之,丹江口市、阳新县、京山县,尤其是天门市和通城县的品质表现不如上述各个产地。因此湖北省纽荷尔脐橙应重点集中在三峡库区这一优势区域内优先发展,同时向其邻近的适宜地区辐射,而在其它产地宜选择小气候适宜地区适当发展。  相似文献   

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华南地区花镜植物资源筛选评价及应用研究   总被引:2,自引:0,他引:2       下载免费PDF全文
为营造物种多样、季相丰富、景观优美的生态经济型花镜,筛选出一批适合于华南地区花镜景观营造的植物种类,并采用层次分析法进行综合评价。结果表明,适合华南地区花镜景观营造的植物305种,隶属于84科221属,主要有爵床科(Acanthaceae)、豆科(Fabaceae)、菊科(Asteraceae)、石蒜科(Amaryllidaceae)等,小乔木、灌木、草本和藤本植物分别有16、127、134和28种;乡土植物100种,占32.79%,外来植物205种,占67.21%。综合评价分析表明,Ⅰ级、Ⅱ级和Ⅲ级花镜植物分别有148、151和6种;层次分析表明,前景植物、中景植物和背景植物分别有106、162和157种;季节分析表明,春、夏、秋和冬季植物分别有216、232、195和128种。这表明可用于华南地区花镜景观营造的灌木和草本植物资源丰富,应用形式多样。  相似文献   

6.
李超荣 《化石》2004,(3):38-40,F003
法国位于欧洲西部,陆地和比利时、卢森堡、德国、瑞士、意大利、西班牙、安道尔和摩纳哥等国家接壤,西北部隔海与英国相望。法国大陆呈六边形,三边临水,三边靠陆,是西欧最大的国家。该国历史悠久而辉煌,是最受欢迎的旅游胜地。秀丽的风光,美丽的历史名城和举世无双的佳肴与美酒,以及独特的文化韵味和一流的购物环境,无不使游客流连忘  相似文献   

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生活史对策   总被引:13,自引:0,他引:13  
1概念和意义生活史是生物学家很熟悉的概念,它可定义为物种的生长、分化、生殖、休眠和迁移等各种过程的整体格局。不同的物种具有不同的生活史特征,例如一年生、二年生和多年生的,一年中只生殖一次的和多次的,有休眠的和无休眠的等等。有卵、幼虫、蛹和成虫各个阶段的完全变态昆虫,有多寄生和复杂生活史的寄生虫,有改变栖息地的候鸟,彼此间生活史的差别是很明显的。比较各个物种的生活史特征,揭示其相似性和分异性,进而联系其栖息地环境条件,探讨其适应性,联系物种的分类地位,探讨各种类型和亚类型生活史在生存竞争中的意义,…  相似文献   

8.
基于MSIASM方法的中国省级行政区体外能代谢分析   总被引:1,自引:0,他引:1  
刘晔  耿涌  赵恒心 《生态学报》2011,31(11):3133-3142
通过社会代谢多尺度综合分析方法,采用社会不同层次人类活动时间、体外能代谢率与人类活动的社会开支和体外能的社会开支等指标,评价我国30个北京、天津、河北、山西、内蒙古自治区、辽宁、黑龙江、上海、福建、山东、河南、湖南、陕西、甘肃、宁夏回族自治区、新疆维吾尔自治区、吉林、江苏、浙江、安徽、江西、湖北、广东、广西壮族自治区、海南、重庆、四川、贵州、云南和青海30个省级行政区的社会代谢状况,识别出限制区域可持续发展的关键因素可持续发展水平,并通过因子分析和相关分析方法,识别限制区域可持续发展的因素。结果表明,该方法社会代谢多尺度综合分析方法适合于中国省级行政区的可持续发展评价;与2003年相比,2007年我国各省级单位的社会生产和消费水平普遍提高。在内蒙古自治区,矿业的迅速发展及其对工业和服务业的剧烈带动作用,造成了体外能代谢改善水平高于全国其他省级行政区。在海南省,整体工业化水平不高,以农业和旅游业为主的产业特点,使其体外能代谢的改善水平低于全国其他省级行政区。在江西和贵州,生产性行业发展过快,而服务业发展的和民生的工程人民生活水平改善发展的滞后,导致生产部门体外能代谢水平提高,而消费部门体外能代谢水平下降。在河北、青海和新疆维吾尔自治区,社会各行业均发展较快,而人民生活水平的改善较慢,使其付薪部门体外能代谢水平提高,而家庭部门体外能代谢水平下降。在安徽和广西壮族自治区,农业生产发展和消费水平提高较快,而工业生产水平和服务业发展有所降低,使其非农生产部门体外能代谢水平下降,而农业和家庭部门的体外能改善水平提高。在山西和上海地区,工业、服务业的发展和人民生活水平改善较叫快,而农业生产发展较慢,导致非农部门和家庭的体外能代谢水平提高,而农业部门的体外能代谢水平有所降低,这为地区可持续发展政策的制定提供了科学依据。与2003年对比,2007年资本和技术聚集是我国大部分地区社会发展的重要影响因素。北京、天津、河北、山西、内蒙古自治区、辽宁、黑龙江、上海、福建、山东、河南、湖南、陕西、甘肃、宁夏回族自治区和新疆维吾尔自治区仍需加大力度调整地区产业结构;吉林、江苏、浙江、安徽、江西、湖北、广东、广西壮族自治区、海南、重庆、四川、贵州、云南和青海继续加大资本技术的引进力度,以解决个省级行政区经济发展中的资本技术聚集与区域产业结构的不协调问题。而且,2007年中国省级行政区社会代谢表现异常,大多数省级行政区社会开支并未随社会发展而增加,社会负担表现为自南方向北方转移的倾向;内蒙古、宁夏和新疆3个矿产资源丰富的省级行政区的经济发展使当地环境承压过重。30个省级行政区中只有上海接近中等发达国家水平,北京、天津、河北等16个省级行政区仍需着力调整区域的产业结构,吉林、江苏、浙江等14个省级行政区仍需着力资本技术的引进力度,中国的社会负担出现南方转移到北方的倾向;与其他国家和地区相比,大部分省级行政区仍处于发展中国家水平,对这些国家和地区曾遇到的不可持续发展问题我们应引以为戒。  相似文献   

9.
城市绿地类型的划分及其在生态城市建设中的意义和作用   总被引:4,自引:1,他引:3  
根据生境和绿地功能把城市绿地划分为10个类型,并阐述了这些类型的组建和管护问题。10个绿地类型包括保护区,植物园,城市公园,城市片林,街心花园、草坪和花坛,道路两旁绿化区,庭园绿地,房顶、墙壁、凉台和室内的绿化,村落生态经济园及生态农业景观。根据归属部门、管理级别、保护对象、管理对象及监控类型的不同,对保护区进行了进一步的划分。城市绿地分类系统的建立既能把城市建设与生物多样性保护相结合,也有助于生物多样性公约的实施,并在维护城市生态安全、美化城市环境、建立具有特色的生物多样性产业、开展生态旅游和生态教育培训、繁荣地方经济和提高当地人民生活水平等方面有重要意义。  相似文献   

10.
98.55W/cm2脉冲微波辐照对大鼠血清生化指标影响的研究   总被引:3,自引:0,他引:3  
二级雄性Wistar大鼠35只,随机分为7组,每组5只,1组为空白对照,其余6组为辐照组以98.55W/cm^2的脉冲微波辐照动物,辐照后1、6、24h和7、14、28d分别采血,用Coulter-JTIR全自动生化仪进行测定,所有数据经Spss8.0统计软件处理,辐射后1h,CRE明显增高(P<0.01),而TP、ALB、AST、LD1、CK、ALP及CHOL均明显降低(P<0.05);辐射后6h,春CRE明显增高(P<0.05),而TP、ALB、LD1、ALP及CHOL均明显降低(P<0.05);辐照后24h,其ALT、GLU、BUN、CRE、AST、LD和HBDH明显升高(P<0.05),而LB和CHOL则明显降低(P<0.05);辐照后7d,其ALT、ALB、GLU、CRE、CK-MB和GGT明显升高(P<0.05),而P和CHOL则明显降低(P<0.05);辐照后14d,其CRE、LD、CK-MB和GGT明显升高(P<0.05),而P和CHOL则明显降低(P<0.01);辐照后28d,其ALT、TP、BUN和CRE明显升高(P<0.05),而ALB、AST、LD1、CK、ALP和CHOL则明显降低(P<0.01)。提示HPPMW可引起大鼠血清多种酶、蛋白及代谢产物的紊乱,即有早期影响,也表现为一定的持续效应。HPPMW可能引起大鼠多系统、多脏器的损伤。  相似文献   

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On the origin of the Hirudinea and the demise of the Oligochaeta   总被引:10,自引:0,他引:10  
The phylogenetic relationships of the Clitellata were investigated with a data set of published and new complete 18S rRNA gene sequences of 51 species representing 41 families. Sequences were aligned on the basis of a secondary structure model and analysed with maximum parsimony and maximum likelihood. In contrast to the latter method, parsimony did not recover the monophyly of Clitellata. However, a close scrutiny of the data suggested a spurious attraction between some polychaetes and clitellates. As a rule, molecular trees are closely aligned with morphology-based phylogenies. Acanthobdellida and Euhirudinea were reconciled in their traditional Hirudinea clade and were included in the Oligochaeta with the Branchiobdellida via the Lumbriculidae as a possible link between the two assemblages. While the 18S gene yielded a meaningful historical signal for determining relationships within clitellates, the exact position of Hirudinea and Branchiobdellida within oligochaetes remained unresolved. The lack of phylogenetic signal is interpreted as evidence for a rapid radiation of these taxa. The placement of Clitellata within the Polychaeta remained unresolved. The biological reality of polytomies within annelids is suggested and supports the hypothesis of an extremely ancient radiation of polychaetes and emergence of clitellates.  相似文献   

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Data on the ontogeny of the posterior haptor of monogeneans were obtained from more than 150 publications and summarised. These data were plotted into diagrams showing evolutionary capacity levels based on the theory of a progressive evolution of marginal hooks, anchors and other attachment components of the posterior haptor in the Monogenea (Malmberg, 1986). 5 + 5 unhinged marginal hooks are assumed to be the most primitive monogenean haptoral condition. Thus the diagrams were founded on a 5 + 5 unhinged marginal hook evolutionary capacity level, and the evolutionary capacity levels of anchors and other haptoral attachement components were arranged according to haptoral ontogenetical sequences. In the final plotting diagram data on hosts, type of spermatozoa, oncomiracidial ciliation, sensilla pattern and protonephridial systems were also included. In this way a number of correlations were revealed. Thus, for example, the number of 5 + 5 marginal hooks correlates with the most primitive monogenean type of spermatozoon and with few sensillae, many ciliated cells and a simple protonephridial system in the oncomiracidium. On the basis of the reviewed data it is concluded that the ancient monogeneans with 5 + 5 unhinged marginal hooks were divided into two main lines, one retaining unhinged marginal hooks and the other evolving hinged marginal hooks. Both main lines have recent representatives at different marginal hook evolutionary capacity levels, i.e. monogeneans retaining a haptor with only marginal hooks. For the main line with hinged marginal hooks the name Articulon-choinea n. subclass is proposed. Members with 8 + 8 hinged marginal hooks only are here called Proanchorea n. superord. Monogeneans with unhinged marginal hooks only are here called Ananchorea n. superord. and three new families are erected for its recent members: Anonchohapteridae n. fam., Acolpentronidae n. fam. and Anacanthoridae n. fam. (with 7 + 7, 8 + 8 and 9 + 9 unhinged marginal hooks, respectively). Except for the families of Articulonchoinea (e.g. Acanthocotylidae, Gyrodactylidae, Tetraonchoididae) Bychowsky's (1957) division of the Monogenea into the Oligonchoinea and Polyonchoinea fits the proposed scheme, i.e. monogeneans with unhinged marginal hooks form one old group, the Oligonchoinea, which have 5 + 5 unhinged marginal hooks, and the other group form the Polyonchoinea, which (with the exception of the Hexabothriidae) has a greater number (7 + 7, 8 + 8 or 9 + 9) of unhinged marginal hooks. It is proposed that both these names, Oligonchoinea (sensu mihi) and Polyonchoinea (sensu mihi), will be retained on one side and Articulonchoinea placed on the other side, which reflects the early monogenean evolution. Except for the members of Ananchorea [Polyonchoinea], all members of the Oligonchoinea and Polyonchoinea have anchors, which imply that they are further evolved, i.e. have passed the 5 + 5 marginal hook evolutionary capacity level (Malmberg, 1986). There are two main types of anchors in the Monogenea: haptoral anchors, with anlages appearing in the haptor, and peduncular anchors, with anlages in the peduncle. There are two types of haptoral anchors: peripheral haptoral anchors, ontogenetically the oldest, and central haptoral anchors. Peduncular anchors, in turn, are ontogenetically younger than peripheral haptoral anchors. There may be two pairs of peduncular anchors: medial peduncular anchors, ontogentically the oldest, and lateral peduncular anchors. Only peduncular (not haptoral) anchors have anchor bars. Monogeneans with haptoral anchors are here called Mediohaptanchorea n. superord. and Laterohaptanchorea n. superord. or haptanchoreans. All oligonchoineans and the oldest polyonchoineans are haptanchoreans. Certain members of Calceostomatidae [Polyonchoinea] are the only monogeneans with both (peripheral) haptoral and peduncular anchors (one pair). These monogeneans are here called Mixanchorea n. superord. Polyonchoineans with peduncular anchors and unhinged marginal hooks are here called the Pedunculanchorea n. superord. The most primitive pedunculanchoreans have only one pair of peduncular anchors with an anchor bar, while the most advanced have both medial and lateral peduncular anchors; each pair having an anchor bar. Certain families of the Articulonchoinea, the Anchorea n. superord., also have peduncular anchors (parallel evolution): only one family, the Sundanonchidae n. fam., has both medial and lateral peduncular anchors, each anchor pair with an anchor bar. Evolutionary lines from different monogenean evolutionary capacity levels are discussed and a new system of classification for the Monogenea is proposed.In agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. EditorIn agreeing to publish this article, I recognise that its contents are controversial and contrary to generally accepted views on monogenean systematics and evolution. I have anticipated a reaction to the article by inviting senior workers in the field to comment upon it: their views will be reported in a future issue of this journal. Editor  相似文献   

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