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1.
植物能直接释放甲烷(CH4)一直被质疑。为了验证活体植物的CH4源汇功能,利用改装的便携式光合仪(Li-6400)采集植物叶片释放的CH4,并通过气象色谱分析甲烷体积分数,初步研究了14种植物叶片的CH4排放情况,并比较了原位和离体枝条叶片CH4排放差异,以及海拔变化对部分植物叶片CH4排放的影响。结果表明,华南地区14种植物叶片CH4排放情况随植物种类而异,无忧树(Saraca dives)、树菠萝(Artocarpus heterophyllus)和海南菜豆树(Radermachera hainanensis)的叶片能直接排放CH4,垂叶榕(Ficus benjamina)则吸收CH4,其他种类植物则有吸收和排放CH4的双重现象。而且,原位和离体枝条采集植物叶片排放CH4的气体浓度没有显著差异,表明离体枝条法采集叶片CH4排放气体适合野外采样。海拔梯度引起的小幅度增温抑制了被测4种植物叶片的CH4排放,并在30 m海拔(增温3℃)的环境中表现出显著的CH4吸收。可见,植物叶片在有氧的环境中可直接排放或吸收CH4,然而其CH4的释放与植物种类和环境因子(如海拔、温度)密切相关。在今后的植物CH4排放清单编制时,应充分考虑环境因子对植物CH4源汇功能的影响,以准确评估森林生态系统的CH4源汇功能。  相似文献   

2.
交通污染区城市绿化植物硫含量分布   总被引:7,自引:1,他引:7  
为探讨城市绿化植物对交通环境中SO2的响应,以远离城市道路的相对清洁区公园生长的植物为对照植物,采集了广东省被广泛栽种的18种园林绿化植物的不同方位的叶片和树皮样品,用硫酸钡比浊法测定了每种植物样品在交通污染区面向机动车行驶方向、面向人行道方向及相对清洁区的植物样品等不同方位的植物叶片和树皮硫含量,分析了绿化植物在同一株植物的不同生长部位和不同环境中硫含量的分布特征。结果表明,交通污染区所有样品的叶片硫和树皮硫含量均高于相对清洁区的样品。其中,远离工厂的交通污染区生长的同一株植物,离机动车道越近,硫含量越高;靠近工厂的交通污染区的同一植物,离工厂近的部位的植物树皮硫含量高于面向机动车道一侧的植物硫含量。  相似文献   

3.
植物根系吸收土壤水分是土壤-植物-大气连续体中水分运动的一个重要环节.本文从土壤-植物-大气连续体入手,对植物根系吸收土壤水分的影响因素,植物根系吸收土壤水分的微观模型及植物根系吸收土壤水分的宏观模型等,进行了介绍和评述.  相似文献   

4.
中国生物入侵的生态分布   总被引:17,自引:3,他引:17  
生物入侵已被列为当今世界最为棘手的三大环境难题(生物入侵、全球气候变化和生境破坏)之一。文章阐述了我国生物入侵的现状,以时间和地理区域为尺度,初步探讨了生物入侵的生态分布特征。指出其特征是:生物入侵对生物多样性造成重大影响,入侵生物的数量逐年增加,具有时间动态性;生物入侵的分布具有纬度地带性规律,纬度越低生物入侵的现象越严重;入侵生物的数量具有地理区域性。  相似文献   

5.
简要介绍了日本的植物遗传资源数据管理系统,以及植物遗传数据的产生过程与管理,该系统以关系数据模型为基础,在UNIX操作系统下运行,主要有身份数据库、存贮数据库和评估数据库三大类。  相似文献   

6.
火力发电厂灰渣场地理化性质对植物生长的影响   总被引:1,自引:0,他引:1  
经实地考察分析,对芜湖火力发电厂灰渣场地理化性质和植物生长的关系进行了研究。结果表明,芜湖发电厂灰渣汤地自然定居的植物仅30种,大部分定居物种适于风力传播的繁殖体,它和渣汤周边的植物繁殖体源有重要关系。灰渣汤地理性质不良,养分不平衡而贫癠和重金属浓度过高是限制植物定居的主要因素。  相似文献   

7.
苯并噻二唑(简称BTH),英文通用名为acibenzolar-S-methyl,是Novatis(现Syngenta)开发的新型植物激活剂,该类药剂的成功开发突破了人们对新农药创制的传统认识.BTH本身无离体杀菌活性,对植株的保护作用表现在该化合物完全降解之后,因此,这一保护作用必定是激活了植物抗性机制的结果.为更好地了解BTH的环境行为,本文研究了BTH在甲醇中降解的动力学。  相似文献   

8.
植物根圈污染生态研究进展   总被引:8,自引:0,他引:8  
阐述了植物根圈的概念,根圈三大结构主成份是(1)植物根系,(2)微生物,(3)土壤或水等,并从它们的相互关系出发讨论了国内外有关根圈污染生态的研究情况,同时提出了根圈污染生态的研究前景和意义。  相似文献   

9.
对蕃茄基因转化的受体系统进行了研究结果表明:在蕃茄离体子叶(或子叶切段)培养中,只加细胞分裂素(Zt或BA)即可使不定芽充分分化,而少量生长素对不定芽的分化反而有抑制作用;在所试验过的多种外植体中,以2/3子叶片处切割子叶所产生的外植体用作转化受体最好;不同蕃茄品种、同一品种的不同外植体及同一外植体的不同培养方式等均对转化频率有一定的影响;通过生长素短期刺激诱导,可解决转基因植物生很困难的问题.  相似文献   

10.
Vc二步发酵离体实验系统的建立   总被引:1,自引:1,他引:0  
以氧化葡萄糖酸杆菌和巨大芽孢杆菌混合培养物的无细胞抽提液为基本反应液,在试管中建立了Vc二步发酵离体实验系统,将底物山梨糖加入反应体系后在pH7.0,35℃下保温24h,2-酮基-L-古龙酸生成,加入巨大芽孢杆菌胞外活性物质对离体系统的产酸没有影响,一定量的L-山梨糖脱氢酶可促进产酸,试验了pH、θ/℃、金属离子、电子受体、去污剂等对该系统产酸的影响,并就其作用机理进行了探讨,结果表明离体系统产酸的最适pH和θ/℃分别是8和.40℃,Fe^3 促进产酸,Co^2 抑制产酸2,6-二氯酚定酚作为电子受体促进细胞膜组分产酸,但对细胞质组分没有影响,Triton X-100和Tween80抑制产酸。  相似文献   

11.
TDZ和CPPU在虎杖组织培养中的应用   总被引:9,自引:0,他引:9  
将高活性细胞分裂素类物质TDZ和CPPU应用于虎杖的组织培养研究.经实验筛选发现,虎杖茎段比叶柄、叶片更容易诱导愈伤组织的形成,其诱导愈伤组织较适的培养基组成为MS 0.5mg/LCPPU 0.2mg/LNAA,适宜的愈伤组织增殖培养基为SH 0.05mg/LTDZ 1.0mg/LNAA;诱导芽分化的适宜培养基为MS 0.05mg/LTDZ 0.5mg/LNAA;促进幼苗生长的培养基为MS 0.1mg/LCPPU 1.0mg/LNAA 0.5%活性炭;快速生根及壮苗的培养基为1/2MS 1.0mg/LNAA 0.5%活性炭.TDZ和CPPU在愈伤组织的诱导、不定芽的分化及组培苗的生长等方面表现出不同的效果.以此方式进行虎杖人工快速繁殖,繁殖系数可达到5~7,繁殖时间缩短为2~3wk.图4表2参12  相似文献   

12.
建立了水生单子叶植物水浮连(Pistia stratiotes Linn.)通过器官发生途径的体久高效再生与繁殖方法.采用叶、茎节和匍匐茎为外植体诱导愈伤组织,只有茎节能够在添加2,4-D和6-BA的MS基本培养基上形成合愈伤组织,而叶和茎在含有不同组合植物激素的培养基上都不能够诱导愈伤产生.将愈伤组织转到添加6-BA和NAA的MS固体分化培养基可以在2wk内形成小苗,将小苗移至含NAA的MS固体生根培养基形成完整的植株.将生根苗转入无植物激素的不同基本液体培养基里比较其生长效果,其中含有2倍大量元素的SH培养基最适合其生长繁殖,在2wk内可由1个小苗每秒殖出10个新的植株.本研究是关于该植物体外再生的首次报道.水浮莲体外再生及繁殖系统的建立不公可以用于在无菌条件下进行基础生理生化研究,还可以用于该植物遗传达室转化系统的建立.由于该植物生长迅速且为无性繁殖,生产成本低,通过基因工程方法表达外源基因将可以用于重组药用蛋白的生产及污染水体的转基因植物修复.  相似文献   

13.
Abstract:  Rural indigenous people are often very knowledgeable about plant and animal species, including their identification and ecology. The use of indigenous knowledge has increasingly attracted attention in scientific circles. The Dai people, a dominant nationality in southwestern Yunnan, China, have developed their own traditional plant classification system. In a case study in Xishuangbanna, we compared the differences in number of plant species identified between scientific and Dai folk classification. The Dai people identified more than 80% of the plant species, and the correspondence between folk and scientific plant species was 87.7%. Our results indicate that folk plant classification could be used in rapid assessment of plant species in certain regions. The use of folk systems of plant classification for rapid biodiversity assessment will contribute to conservation of both indigenous knowledge and regional biodiversity.  相似文献   

14.
Research on interactions among wave, current, and vegetation has received increasing attention. An explicit depth-averaged hydrodynamic model coupled with a wave spectral model (CMS-wave) was proposed in this study in order to simulate the wave and wave-induced current in coastal waters. The hydrodynamic model was based on the finite volume method while the intercell flux was computed by employing the Harten–Lax–van Leer approximate Riemann solver to investigate the dry-to-wet interface, and the drag force of vegetation was modeled as the sink terms in the momentum equations. The CMS-wave model was used to investigate the non-breaking and the breaking random waves propagation in vegetation fields. Afterwards, an empirical wave energy dissipation term with plant effect was derived to represent the resistance induced by aquatic vegetation in the wave-action balance equation. The established model was calibrated and validated with both the experimental and field data. The results showed that the wave height decreased significantly along the wave propagation direction in the presence of vegetations. The sensitivity analysis for the plant density, the wave height, and the water depth were performed by comparing the numerical results for the wave height attenuation. In addition, wave and wave-induced current through a finite patch of vegetation in the surf zone were investigated as well. The strong radiation stress gradient could be produced due to the variation of the energy dissipation by vegetation effect in the nearshore zone, which impacted the direction and amplitude of the longshore current. The calculated results showed that the coupling model had good performance in predicting wave propagation and the current over vegetated water regions.  相似文献   

15.
Abstract: Flying foxes are animals of extraordinary ecological and economic importance throughout forests of the Old World tropics Nearly 200 species play an essential role as forest pollinators and seed dispersers, yet they are frequently misunderstood intensely persecuted and exceptionally vulnerable to extinction Their role in the propagation of numerous important plants remains virtually uninvestigated. However, our review of already available literature demonstrates that at least 289 plant species rely to vatying degrees on large populations of flying foxes for propagation. These plants, in addition to their many ecological contributing produce some 448 economically valuable products. The fact that flying foxes are increasingly threaten and that few baseline data exist on population trends is cause for concern Many appear to be in severe decline, and several species are already extinct. We present initial observations on flying fox importance and survival threats in hopes of highlighting research and conservation needs.  相似文献   

16.
VA菌很是由球囊霉目的结合菌与植物根组织形成的一类共生联合体,在农林业生产中具有巨大的应用前景.众多研究表明,VA菌根真菌是一种亟待开发利用的微生物资源.本文详细介绍了VA菌根真菌的繁殖方法,探讨了VA菌根菌剂的生产途径;文中还讨论了测定菌剂接种潜力的评价方法,重点介绍了最或然数测定法.  相似文献   

17.
Abstract: Compatibility between the belowground mutualists of resident species and the needs of immigrant species will strongly influence the successful transition from one perennial plant community to another during climate change. A hiatus in the overlap between plant species that maintain a positive link with the soil ecosystem could result in site capture by weeds and rapid degradation of the productive capacity of soils. We discuss instances in which such rapid degradation has occurred and argue for the crucial importance of protecting plant-soil links in the coming decades through maintaining biodiversity and utilizing management practices that help plants keep a firm grip on the soil. Examples of the latter include partial and dispersed cutting in forestry, use of green cover crops in agriculture and grazing intensities that permit degraded range to rebuild.  相似文献   

18.
Ecological Correlates of Extinction Proneness in Tropical Butterflies   总被引:7,自引:0,他引:7  
Abstract:  Widespread and rapid losses of natural habitats and biodiversity have made the identification of extinction-prone species a major challenge in conservation biology. We assessed the relative importance of biologically relevant species traits (e.g., body size, ecological specialization) obtained from published records to determine the extinction probability of butterflies in a highly disturbed tropical landscape (i.e., Singapore). We also developed a taxon-specific model to estimate the extinction proneness of butterflies in Southeast Asia. Logistic regression analyses showed that adult habitat specialization, larval host plant specificity, geographical distribution, sexual dichromatism, and congenor density were significant and independent determinants of butterfly extinctions in Singapore. Among these traits, specificity of larval host plant and adult habitat specialization were the best correlates of extinction risks. We used this phenomenological extinction-regression model to estimate the relative extinction proneness of 416 butterfly species in Southeast Asia. Our results illustrate the utility of available taxon-specific data for a localized area in estimating the extinction proneness of closely related species on a regional scale. When intensive field studies are not forthcoming, especially in regions suffering from rapid biodiversity losses (e.g., Southeast Asia), similar approaches could be used to estimate extinction threats for other taxonomic groups.  相似文献   

19.
生物快滤池深度处理城市污水的性能及pH值变化规律   总被引:1,自引:0,他引:1  
采用生物快滤池对城市污水厂二级出水进行深度处理的试验表明,生物快滤池对进水水质变化有很大的适应性,除卫生学指标外,其它指标出水绝大部分时间可满足生活杂用水水质标准(CJ25.1-89)中的洗车标准。随着进水水质的不同,生物快滤池中生化反应类型也随之变化,相应地滤池出水pH值也有不同的变化规律。可以通过生物快滤池进出水pH值的变化情况来判断滤池内生化反应类型和COD或氨氮指标的去除效果。  相似文献   

20.
The objectives of this study were to examine the effect of TDZ and BAP on shoot proliferation and to develop a satisfactory rooting procedure for in vitro propagation of caper (Capparis spinosa L). TDZ was found to be more effective than BAP in shoot production. The highest shoot number per explant (45.7) was achieved on the media that contained 4.54 microM TDZ in the absence of IAA. TDZ at 4.54 microM alone or in combination with 0.57 microM IAA did not inhibit shoot elongation, although they produced the most shoots. Dipping the caper shoots in the solution of IBA at 24.6 microM for 10 minutes before planting on MS media, improved the rooting percentage up to 80.5% under a 16 hr photoperiod.  相似文献   

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