首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 218 毫秒
1.
本文通过对嘉陵江上游低山暴雨区不同植被类型的初步研究。不同植被类型的氮库总储量分别为:6 787.27 kg.hm-2、7 115.39 kg.hm-2、6 951.06 kg.hm-2。其中不同植被类型中活体生物量分别为:136.43 kg.hm-2、210.40 kg.hm-2、169.66 kg.hm-2,凋落物层分别为:31.06 kg.hm-2、38.96 kg.hm-2、40.05 kg.hm-2,土壤(0-40cm)中分别为:6 619.73 kg.hm-2、6 866.03 kg.hm-2、6 741.35 kg.hm-2。不同植被类型土壤中的氮分别占总储量的97.53%、96.50%、96.98%,活体生物量分别占2.01%、2.96%、2.44%,而凋落物层分别仅占0.46%、0.55%、0.58%。结果表明,低山暴雨区3种不同植被类型的N主要分布在土壤中,而在活体生物量和凋落物层中只占很少的一部分。3种不同植被类型树干径流的氮含量分别为:0.44 kg.hm-2、0.553 kg.hm-2、0.851kg.hm-2,林分穿透雨氮含量分别为:12.649 kg.hm-2、12.551 kg.hm-2、13.291 kg.hm-2,地表径流氮的输出量分别为:0.55 kg.hm-2、0.55 kg.hm-2、1.27 kg.hm-2。不同植被类型氮的生物循环:湿地松林吸收量、存留量、归还量、循环系数分别为:37.561 kg.hm-2.a-1、6.497 kg.hm-2.a-1、31.064 kg.hm-2.a-1、82.703%,刺槐林吸收量、存留量、归还量、循环系数分别为:48.976 kg.hm-2.a-1、10.019 kg.hm-2.a-1、38.957 kg.hm-2.a-1、79.543%,混交林吸收量、存留量、归还量、循环系数分别为48.127 kg.hm-2.a-1、8.079 kg.hm-2.a-1、40.048kg.hm-2.a-1、83.213%。吸收量、存留量均是刺槐林〉混交林〉湿地松林,归还量是混交林〉刺槐林〉湿地松林。结果表明,3种植被类型处于良好的养分积累状态,有利于系统的稳定持续发展。  相似文献   

2.
河南铁线莲属植物分类学研究(英文)   总被引:1,自引:0,他引:1  
铁线莲属(Clematis L.)是一个在分类上较困难的类群,种类多,形态变化大。全球铁线莲属植物有350余种,中国有150余种。2006年7~8月我们对河南四大山区的铁线莲属植物种类进行了调查、采集和鉴定,标本存放于河南农业大学标本馆(HEAC),此外我们还认真观察了中国科学院植物研究所标本馆(PE)等国内各大标本馆的铁线莲属植物标本。结果表明河南铁线莲属植物24种和11变种,按照王文采等的铁线莲属新分类系统分别隶属于4亚属、7组、11亚组、15系,其中首次报道了半钟铁线莲(C.sibiricavar.ochotensis)和长冬草(C.hexapetalavar.tchefouensis)为河南铁线莲属植物新记录,首次报道了Clematis honanensisS.Y.WangC.L.Chang’作为Clematis pseudootophoraM.Y.Fang in W.T.Wang的新异名。增补《河南植物志》(1981)中未记录的有5种5变种:女萎(C.apiifoliaDC.)、毛萼铁线莲(C.hancockianaMaxim.)、大花威灵仙(C.courtoisiiHand.-Mazz.)、芹叶铁线莲(C.aethusifoliaTurcz.)、巴山铁线莲(Clematis pashanensis(M.C.Chang)W.T.Wang)、扬子铁线莲(C.puberulaHook.f.et Thoms.var.ganpiniana(Levl.et Vant.)W.T.Wang)、狭裂太行铁线莲(C.kirilowiiMaxim.var.chanetii(Levl.)Hand.-Mazz.)、大花绣球藤(C.montanaBuch.-Ham.ex DC.var.grandifloraHook.)、毛叶威灵仙(C.chinensisOsbeck.var.vestita(Rhed.Wils.)W.T.Wang)、狭卷萼铁线莲(Clematis tubulosaTurcz.var.ichangensis(Rehd.Wils.)W.T.Wang)。订正了《河南植物志》(1981)中6个分类群的学名:将C.uncinataChamp.var.biternataW.T.Wang作为C.uncinataChamp.的异名,C.brevicaudataDC.var.filipesRhed.作为C.puberulaHook.f.et Thoms var.tenuisepala(Maxim.)W.T.Wang的异名,C.brevicaudataDC.var.tenuisepalaMaxim.作为C.puberulaHook.f.et Thoms.var.tenuisepala(Maxim.)W.T.Wang的异名,C.argentilucida(Levl.et Vant.)W.T.Wang作为C.grandidentata(Rehd.et Wils.)W.T.Wang的异名,C.obtusidentata(Rhed.et Wils.)H.Eichler作为C.apiifoliaDC.var.argentilucida(Levl.et Vant.)W.T.Wang的异名;将Clematis ternifloraDC.var.latisepalaM.C.Chang作为Clematis pashanensisvar.latisepala(M.C.Chang)W.T.Wang.的异名。  相似文献   

3.
外担子菌属(Exobasidium)的真菌引起树木的细胞增生性和肥大性病害.本研究基于PSA培养基上菌落的形态和性状的模糊解析,以及分离菌株在不同温度、pH值、氮源、碳源下生长曲线的模糊解析和28S rDNA-PCR-RFLP解析,分布于日本的12个种和1个变种的外担子菌属真菌的35个分离菌株被分类为18个菌群.其中9个菌群和传统分类的种是一致的,这些种包括:坏损外担子菌(E.vexans Mass)、网状外担子菌(E.reticulatum Ito et Sawada)、山茶外担子菌(E.camelliae Shirai)、E.cylindrosporium Ezuka、E.shiraianum P.Heen.、E.hachijoense Otani, Kakishima et Iijima、E.bisporum Sawada et Ezuka、E.pievidis-ovalifoliae Sawada和E.symploci-japonicae Kusano et Tokubuchi;细丽外担子菌(E.gracile (Shirai)Sydow)的7个菌株分化为4个菌群,表现了种内的地理、寄主分化;日本外担子菌(E.japonicum Shirai)的7个菌株分化为5个菌群,表现了种内的寄主分化;E.yoshinagai P.Heen.和E.otanianum Ezuka var. satsumense Zhang et Arai的菌株以及E.japonicum的3个菌株被分类为1个菌群.  相似文献   

4.
苏铁镰刀菌球茎腐烂病化学防治技术研究   总被引:1,自引:0,他引:1  
林间调查结果表明:德葆苏铁Cycas debaoensis、四川苏铁C.szechuanensis、十万大山苏铁C.shiwandashanica为苏铁镰刀菌Fusarium solani球茎腐烂病易发病种类;海南苏铁C.hannanensis、元江苏铁C.parvulus和叉叶苏铁C.micholitzii是中等感病品种;越南苏铁C.tonkinensis、贵州苏铁C.guizhouensis、叉孢苏铁C.segmentifida、攀枝花苏铁C.panzhihuaensis、仙湖苏铁C.fairylakea、石山苏铁C.miquelii、单羽苏铁C.simplicipinna、多羽苏铁C.mutltiflrondis为较抗病品种;苏铁C.revoluta和鳞秕苏铁Zamia purouracea是高度抗病品种.在空气干燥的月份,以切除病部+75%酒精表面消毒+涂上含有杀虫剂的50%多菌灵WP处理最好,防治效果100%.在雨水多的月份,以切除病部+75%酒精表面消毒+涂上含有杀虫剂的50%多菌灵粉剂+透光防雨罩处理最好,防治效果83.3%.在化学防治过程中,关键要做到病部切除彻底、表面消毒彻底、防治用的药剂充足,避免后期新伤口产生,才能有效地治疗发病苏铁.  相似文献   

5.
在鉴定2006年以及以前调查采集、拍摄的植物中,共鉴定出湖南新记录种16个,即:卵叶卷耳Cerastium wilsonii Takeda、圆穗蓼Polygonum macrophyllum D.Don、齿裂大戟Euphorbia dentate Michx.、柳叶绣球Hydrangea stenophylla Merr.et Chun、阔叶丰花草Spermacoce latifolia Aubl.、串叶松香草Silphium perfoliatum Linn.、聚合草Symphytum officinale Linn.、三裂叶薯Ipomoea triloba Linn.、鱼黄草Merremia hederacea(Burm.F.)Hall.f.、菱叶直瓣苣苔Ancylostemon rhombifolius K.Y.Pan、江西半蒴苣苔Hemiboea subacaulis Hand.-Mazz.var.jiangxiensis Z.Y.Li、闽赣长蒴苣苔Didymocarpus heucherifolius Hand.-Mazz.、大花万寿竹Disporum megalanthum F.T.Wang et T.Tang、少花万寿竹Disporum uniflorum Baker、花格斑叶兰Goodyera kwangtungensis C.L.Tso、翘距虾脊兰Calanthe aristulifera Rchb.f..其中丰花草属Spermacoce、鱼黄草属Merremia、直瓣苣苔属Ancylostemon 3属为湖南省新记录属.  相似文献   

6.
美洲热带地区有两种名贵树木,桃花心木和巴西木. 桃花心木主要分布在西印度群岛的多米尼加、巴哈马、古马、牙买加,中美洲的洪都拉斯和南美洲的哥伦比亚、委内瑞拉和巴西等国.我国广东省已有引种. 桃花心木是热带雨林中生长的一种高大的常绿乔木,高达25米,属楝科.多米尼加人尊它为国花.叶为偶数羽状复叶,有4~12对小叶.春夏开花,白色花瓣.蒴果较大,坚硬木质.内有种子,用来榨油,在工业上应用.  相似文献   

7.
黄芩(Scutellaria baicalensis Genorgi)为唇形科的植物.别名:元芩,山茶根,黄芩茶,黄金条根.以根入药,味苦,性寒.有清热、解毒、止血作用,主治热病烦渴感冒、目赤肿痛、肺热咳嗽、肝炎、湿热黄疸、痈肿疖疮;此外,黄芩叶或嫩茎叶可代茶饮用,预防中暑.黄芩种子可供药用,用于肠癖脓血.主产黑龙江、辽宁、河北、山东、内蒙古等省区.生长于石砾、山地阳坡、山顶、丘陵坡地、砂质草地等地.  相似文献   

8.
刘灏  陈彦芹 《河北林果研究》2004,19(Z1):533-536
西藏的麻黄属(EphedraL.)资源较为丰富,有7种,是西藏植被中无叶灌丛的主要建群种之一,其山岭麻黄(E.gerardianaWall.exStapf)、西藏中麻黄(E.intermediavar.tibeticaStapf)、藏麻黄(E.saxatilisRoyleexFlorin),分别建成山岭麻黄群系(Form.E.gerardiana)、西藏中麻黄群系(Form.E.intermediavar.tibetica)、藏麻黄群系(Form.E.saxatilis),其中单子麻黄(E.monospermaGmel.exC.A.Mey.)所含的麻黄碱总量高达2.467%,是已知的麻黄碱(Ephedrine)含量最高的种类,可作为首先开发利用的种类.  相似文献   

9.
通过对贵州境内采集的植物标本鉴定和相关文献检索,报道了贵州的10个新记录种,其中1个新记录种为新记录属。它们是勿忘草Myosotis silvatica Ehrh.ex Hoffm.、短小蛇根草Ophiorrhiza pumila Champ.ex Benth.、细叶亚婆潮Hedyotis auricularia L.var.mina W.C.Ko、多刺山黄皮Fagerlindia depauperata(Drake)Tirveng、短梗乌饭Vaccinium brevipedicellatum C.Y.Wu ex Fang et Z.H.Pan、林生越橘Vaccinium sciaphilum C.Y.Wu、变叶树参Dendropanax proteus(Champ.)Benth.、滇赤杨叶Alniphyllum eberhardtii Guill、滇黄堇Corydalis yunnanensis Franch.、矮小山麦冬Liriope minor(Maxim.)Makino,新记录属为勿忘草属。  相似文献   

10.
1.中耕除草结合间作.适时进行中耕除草.杨树林地间作应以矮秆作物为主,如豆类、花生等. 2.灌溉施肥.5月下旬至8月下旬是杨树材积生长旺盛时期,土壤相对含水量应保持在70%左右.为保证杨树的快速生长,在土壤含水量低于45%时应及时灌溉,并在灌溉前追施化肥,氮、磷、钾的比例为3:1:0.5.  相似文献   

11.
东台市生态农业建设研究   总被引:1,自引:0,他引:1  
总结了东台市生态农业建设所取得的成绩,深入分析了生态农业建设存在的若干问题,针对性地提出了发展东台市生态农业的对策建议。  相似文献   

12.
竹材应用的新领域--纺织工业   总被引:2,自引:0,他引:2  
通过对竹材在纺织上的应用研究现状做了客观的总结分析,指出目前存在的问题,特别对天然竹纤维开发的可行性及方法进行了探讨。结果表明:再生竹纤维的加工工艺还需不断完善;天然竹纤维的加工还存在很多问题。离工业化生产还有很长的路要走;两种纤维不可混淆。  相似文献   

13.
A region can conceptually be tessellated into polygons at differentscales or resolutions. Likewise, samples can be taken from theregion to determine the value of a polygon variable for eachscale. Sampled polygons can be used to estimate values for otherpolygons at the same scale. However, estimates should be compatibleacross the different scales. Estimates are often required forzones within a region, where a region might be a state and countiescould be the zones. A method is developed for estimating high-resolution(pixel) values that are constrained to be compatible with resultsfor lower resolution values. The high-resolution values areconstrained to sum to totals for zones within a region, wherethe totals are being simultaneously estimated from measurementstaken at a different scale. If the zone estimates are unbiased,then the pixel-based estimates for the zone will be less biased.Sums of pixels in arbitrary polygons are thereby constrainedto approach unbiased estimates. Approximate variance estimatorsare developed for the summed pixel estimates. Two example applicationsare provided. The first example is based on simulated data andverifies that the proposed variance estimators give reasonableresults. The second example estimates the volume in a circlearound a possible mill site in North Carolina. This exampleuses publicly available US Forest Service inventory data andsimulated inventory data that the mill would provide.  相似文献   

14.
The 18 species of bird studied originally are known to belong to muscicapids, robins and sylviids of passerines, but some dis- putations are always present in their classification systems. In this experiment, phylogenetic relationships of 18 species of passerines were studied using Adenylate Kinase lntron 5 (AKS) sequences and DNA techniques. Through sequences analysis in comparison with each other, phylogenetic tree figures of 18 species of passerines were constructed using Neighbor-Joining (N J) and Maximum-Parsimony (MP) meth- ods . The results showed that sylviids should be listed as an independent family, while robins and flycatchers should be listed into Musci- capidae. Since the phylogenetic relationships between long-tailed tits and old world warblers are closer than that between long-tailed tits and parids, the long-tailed tits should be independent of paridae and be categorized into aegithalidae. Muscicapidae and Paridae are known to be two monophylitic families, but Sylviidae is not a monophyletic group. AK5 sequences had better efficacy in resolving close relationships of interspecies among intrageneric groups.  相似文献   

15.
政治生态学及其在林业上的应用和发展   总被引:1,自引:0,他引:1  
简介了政治生态学的概念及其研究框架,并用其思路探讨了资源保护和经济发展的矛盾.矛盾的解决在于集中力量,高起点先发展局部和解决事物的重要方面的问题,再逐一推进.原始自然资源的价值更重要的在于它的原著性和不可替代性.生物多样性保护和生态旅游为原著性和不可替代性转变为经济价值提供了良好的机缘.我国林业的重点应由扩大森林面积转变到原始自然资源保护.在未被破坏地区实施高起点的原始自然资源保护和生态旅游,在已破坏地区实行近自然林业经营.林业的发展在于转变观念,各行各业参与,高起点先发展局部和事物的重要方面.  相似文献   

16.
测定研究了不同直径兰考泡桐的根材和枝桠材的各种解剖因子及其基本密度,结果表明:兰考泡桐根材和枝桠材构造区别明显,不同直径的根材和枝桠材木材解剖性和基本密度均有变异,仅少数指标差异显著,根材和枝桠材相比,基本密度和木纤维含量为枝材<根材,其余因匀为根材>枝材。进一步分析论证表明,根材和枝桠材是刨花板的好原料;而枝材适宜于生产纤维板,但根材不合适。  相似文献   

17.
Short rotation forests, consisting of various willows (Salix spp.), are suitable vegetation filters with regard to removal of nutrients from municipal sewage sludge, wastewater, leakage water and bioash (wood ash). As long as contents of heavy metals and known organic compounds are kept below accepted limit values, such waste oducts can be regarded as valuable nutrient resources, and particularly when the vegetation is produced for energy purposes instead of for direct or indirect human consumption. The benefit is three-fold: (i) purification of municipal waste using natural circulation, (ii) production of biomass for energy purposes, (iii) reduction of air pollution when burning wood instead of fossil fuels. Most Salix plantations can be used as recipients of sludge and ash as well as be irrigated with wastewater from sewage plants or with leakage water from dumps. Regarding waste and leakage water irrigation, a combined artificial wetland for winter conditions and a willow vegetation filter during the growing season can be used for the purification The welland should be planted with a suitable vegetation cover, which can be harvested in order to remove maximal amounts of nutrients from the system. This biomass can be used as fuel or in compost. There are also indications that some willow clones are capable of taking up certain heavy metals, while others are not. This is beneficial when growing willow on contaminated soils, which either could be purified or just be used for such plantations.  相似文献   

18.
新型五色草花坛从景天科植物中选出,在自然低温条件下和干旱季节中试验,比老五色草抗寒抗旱,更具有应用价值。用于花坛造型显现出红、绿、黄、粉和紫粉五种色颜动态变化,不同于老五色草的静态拼色,而且,整体越冬完好。母株冬储和繁殖均在露地进行,改变了老五色草在加温温室内越冬和需要在保护地繁殖的传统方式,花坛模纹时间提前1个月,观赏期延长60d,一年建植多年享用。新型五色草可取代现行的老五色草,在寒冷地区广泛应用。  相似文献   

19.
Principles and criteria for the objective assessment of ‘damage' are presented as a basis for objective discussion and to promote targeted research. The topic will be considered from three different viewpoints – theoretical background, silviculture, and nature conservation. Examples of methods to assess ‘damage' are given, as are the criteria and indicators for target values for growing stock.

The objective existence of damage must be established by comparing the current status against a target. Only if the present status no longer permits achievement of the desired target can damage be claimed. The same is true for verification of ‘benefit' resulting from an impact leading to a favorable status. Establishing the degree of browsing damage on forest regeneration allows forecasts of damage to be made, but the actual damage can only be determined at a future time, for example when the timber is harvested or when the function of the forest is seen to have been compromised. The earlier the forecast is made the more uncertain it is, because the compensatory responses of the forest can only be forecast to a limited extent. Silvicultural targets depend on the requirements of both, the forest owner and the public. Main indicators for assessing ungulate damage on forest regeneration are total tree density, species composition, and height structure. From the viewpoint of nature conservation the determination of target values is particularly difficult. The measurement of damage involves choosing the most relevant indicators of favorable condition of woodland habitats and assessing these in the field. With adequate resources this can be done quantitatively using a wide range of standard field measurement techniques. Alternatively, where resources are limited, it can be done qualitatively by scoring different areas for a range of indicators. As yet, such qualitative methods are in their infancy. Specific research is now being undertaken in some European countries.  相似文献   


20.
调查结果表明 ,桉树在引种驯化区域内 ,渐尖赤桉和薄皮大叶桉具有生长快、抗性强的特点 ,适合在宜昌区域内作为用材树种栽培发展 ;大叶桉、葡萄桉、细叶桉虽易受风折、雪折和冻害 ,但萌发能力强 ,适宜在本地区内进行矮林作业营造薪炭林或桉油林。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号