南岳衡山种子植物区系地理分析——南岳衡山植物区系研究(二)

采用查阅资料和线路调查与样地调查相结合的方法,研究南岳衡山种子植物区系的地理成分,结果表明:南岳衡山有种子植物164科中有12个分布型8个变型,692属中有14个分布型18个变型,1 572种中有14个分布型和非中国特有种的11个变型以及中国特有种的13个变型;类群分布型及变型组成复杂,联系广泛,以属的分布型组成的复杂性和联系的广泛性最明显;不同分布型对不同分类群区系地理属性的影响程度不一样;14、9、3、7和8分布型的属,15、8和14分布型的种对植被组建影响较大。种子植物区系科、属、种的世界广布成分由科的33.54%到属的8.52%,再到4.58%;除世界广布以外,热带成分占总类群数的比例由科的62.38%到属的46.29%,再到种的25.67%;温带成分由科的37.61%,到属的53.71%,再到种74.33%。区系中科以热带成分为主,属的热、温带成分基本平衡,种以温带成分为主。现代种子植物区系为典型亚热带性质,表现出华东植物区西部地区的植物区系特点;区系中有1个中国特有科16个中国特有属533个中国特有种,其中湖南特有11种,衡山特有1种。     

日本北海道北部寒温带森林流域林冠层凋落物及其养分归还量的景观格局(英文)

Within a forested watershed at the Uryu Experimental Forest of Hokkaido University in northern Hokkaido, overstory litterfall and related nutrient fluxes were measured at different landscape zones over two years. The wetland zone covered with Picea glehnii pure stand. The riparian zone was deciduous broad-leaved stand dominated by Alnus hirsuta and Salix spp., while the mixture of deciduous broadleaf and evergreen conifer dominated by Betula platyphylla, Quercus crispula and Abies sachalinensis distributed on the upland zone. Annual litterfall averaged 1444, 5122, and 4123 kg.hm^-2·a^-1 in the wetland, riparian and upland zones, respectively. Litterfall production peaked in September-October, and foliage litter contributed the greatest amount （73.4%-87.6 %） of the annual total litterfall. Concentrations of nutrients analyzed in foliage litter of the dominant species showed a similar seasonal variation over the year except for N in P glehnii and A. hirsuta. The nutrient fluxes for all elements analyzed were greatest on riparian zone and lowest in wetland zone. Nutrient fluxes via litterfall followed the decreasing sequence： N （11-129 kg.hm-2.aq） 〉 Ca （9-69） 〉 K （5-20） 〉 Mg （3-15） 〉 P （0.4-4.7） for all stands. Significant differences were found in litterfall production and nutrient fluxes among the different landscape components. There existed significant differences in soil chemistry between the different landscape zones. The consistently low soil C：N ratios at the riparian zone might be due to the higher-quality litter inputs （largely N-fixing alder）.     

Altitudinal patterns of the flora of seed plants of Dawei Mountain in Yunnan Province, south China

Altitudinal gradient incorporates multiple resource gradients, which vary continuously in different fashions. It is important to study the mountain floristic patterns along altitudinal gradients, which reveal the regular pattern of the flora along the environmental gradients, the changing trend of biodiversity patterns along the altitudinal gradient, and relevance of biological fitness. To explore the compositional characteristics and ecological significance of floristic patterns along altitudinal gradient in China National Nature Reserve of Dawei Mountain in the southeast of Yunnan Province, field investigations have been made to the flora along the two routes of the southwest slope and the northeast slope of the said reserve, including a vertical vegetation transect. Meanwhile, further investigations have also been made to the flora of Dawei Mountain, which has been accounted for in the literature, as Flora Yunnan, The Seed Plant in Yunnan, and so on. The structural characteristics of the flora and the altitudinal distribution pattern of its floristic components were analyzed. By applying systematic cluster analysis, the altitudinal position of the dividing line of floristic changes along altitudinal gradient was detected, and the effects of the montane climate on the vertical variation of floristic composition were studied. Conclusions were put forward. This paper can be summarized as follows: (1) The obvious boundary that differentiates tropical floristic elements is located at the altitude of approximately 1,500 m; it is reasonable to stipulate the boundary line between tropical rain forests and the evergreen broad-leaved forests. (2) The vertical vegetation spectrum made by cluster analysis shows that humid rain forests are below 700 m a.s.l, montane rain forests are between 700 and 1,500 m, monsoon evergreen broad-leaved forests are between 1,300 and 1,800 m, and montane mossy evergreen broad-leaved forests are above 1,800 m a.s.l. Nonrepresentative montane mossy dwarf forests (above 2,100 m) in the area are distributed in windward sides and in barren land on the mountain slopes. __________ Translated from Acta Phytoecologica Sinica, 2005, 29(6): 894–900 [译自: 植物生态学报]     

柠条锦鸡儿组培苗继代培养中矿质元素的吸收规律

比较柠条锦鸡儿在MS、WPM、B5三种基本培养基中对P、K、Ca、Mg、Mn、Cu等主要矿质元素的吸收规律,用向量分析方法找出三种基本培养基中的限制因子.结果表明:矿质养分整体供应水平是影响柠条锦鸡儿组培苗吸收矿质元素的关键因子;除此之外,MS培养基的Ca、P水平偏低,WPM和B5培养基的主要限制因子分别为K、Mn和Ca、P、K.     

Litter dynamics of six multipurpose trees in a homegarden in Southern Kerala, India

Multipurpose trees, the integral components of homegardens, contribute significantly to the closed nutrient cycling processes and sustainability of the ecosystem. Although, the litter production and probable nutrient returns via litter in homegardens have been documented, quantification and characterization of the decomposition and bioelement release from the litter have received relatively little scientific attention. The objective of the present study is to explore the litter dynamics of six locally important multipurpose trees (Mangifera indica L., Artocarpus heterophyllus Lamk., Anacardium occidentale L., Ailanthus triphysa Dennst., Artocarpus hirsutus L. and Swietenia macrophylla L.), in an agroforestry homegarden in Southern Kerala, India. Litterfall and nutrient additions in the six species ranged from 383 to 868 g m⁻² yr⁻¹, nitrogen, 6.4 to 8.8, phosphorus, 0.17 to 0.42 and potassium, 1.1 to 2.8 g m⁻² yr⁻¹. The annual litter output in the homegarden was 425 kg with A. hirsutus, M. indica, A. heterophyllus and A. occidentale recording significantly higher litter and nutrient additions. Leaf litter decay studies revealed A. heterophyllus and A. occidentale to be the most labile litter species and S. macrophylla the most recalcitrant. The decay rate coefficients varied significantly among the species. Foliage decomposition rates related to the initial chemical composition of the litter revealed best correlation with lignin. NPK release was almost complete by the end of decay in all species inspite of the initial phases of accumulation observed for nitrogen and phosphorus. Two-way analysis of variance test revealed significant differences in the contents of the three elements as a function of species and time elapsed. Macronutrients were released in the order K>N/P. The higher rates of decay and nutrient turnover in M. indica, A. heterophyllus and A. occidentale foliage indicated the potential of using these species’ litter as nutrient inputs in agriculture while A. triphysa, A. hirsutus and S. macrophylla perform better as organic mulches taking a longer time for decay and hence nutrient release.     

9种壳斗科树种坚果3种矿质元素及Vc含量分析

壳斗科(Fagaceae)主要分布在亚洲东南部,全球约900种。我国大多数地区通常把壳斗科植物的坚果都称为橡实,有些省区仅将栎属(Qucercus L.)树种的坚果称之为橡实,而李世华等认为橡实又叫橡子;显然,橡实或橡子均指壳斗科植物的坚果。     

Productivity and nutrient cycling in an agroforestry ecosystem for interplant of pineapple and coconut

lntroductionCoconut(Cocosnucifera)isanimportanteconomicplantinthetropicalareas.Butinthetraditionalcoconutplantation,theroutinespaceintherowsis7.5mX7.5m.Sothefieldareasabout75%werenotefficientlyused.Inrecentyears,Indonesiahasmadegreateffortstodevelopanagroforestrysystemofcoconutinterplantedwithpineapple(Satyabalan1986).Asthepineapplehasacertainamountofshade-resistance,thissystemcannotonlymakefulluseofthesoilresources,butalsogreatlyimprovethebiomassproductivityofthewholesystem.Buttheresearchab…     

THE CHARACTERISTICS OF THE NUTRIENT CYCLING IN BIRCH STANDS WITH DIFFERENT AGE STAGES

SuccessionisthedynanucdeveloPInentofecosystemswhichcanbecharactetindbyenergyandndneralcyclings.Eachsuccessionstagehasitscharaceristicsofelementcycling.SomeschOlarshaveStatedbutbrieflawsofnutrienCyclinginsuccessionstagesI"3I.InthespaPer,thenutrientcyclingcharacterishcsofbirchsuccessionseriesinXiaokinganlingwerediscussed.SwrYAasAroarernoDSThestUdyareaislocatedinLiangshniNatUralReservesinthendddieofXiaox-ing'anlilg(l28"53,2o'rE,47olo'5O"N).Theclimat6belongstocontinentalmonsoonclimate,W…     

土壤养分分布特征研究

本试验以黑龙江省宾县三宝乡幸福村耕地土壤为研究对象,基于在研究区域选取的20个地块,根据野外调查采样和室内分析的方法进行土壤养分测定。测定养分为土壤有机质、全磷、速效氮、速效钾、速效磷及土壤pH值。试验目的为研究耕地土壤养分分布特征和供肥特性,并进行对比分析,以期为指导合理施肥和培肥土壤提供依据。结果表明:幸福村耕地土壤养分中P、K空间分布特征较为明显,土壤N含量普遍较高,有机质含量不高。因此,幸福村大田作物施肥方案中N可采用同一标准,均量管理,磷肥、钾肥应分区施用。