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凤眼莲根对东海原甲藻生长的抑制作用及机制研究 总被引：8，自引：0，他引：8
观察凤眼莲Eichhornia crassipes根粉末及丙酮提取物对东海原甲藻Prorocentrum donghaiense生长的影响,比较分析根系丙酮提取物中的化学成分以及不同成分抑藻效果,探讨凤眼莲根对藻类生长的抑制作用及其化学基础。结果显示,1.5g.L-1以上的凤眼莲根粉末可完全抑制东海原甲藻的生长。实际浓度0.019g.L-1的凤眼莲根丙酮提取物对东海原甲藻可产生50%的抑制率。N-苯基-2-萘胺浓度为1mg.L-1时,第6天对东海原甲藻的抑制率超过60%。浓度50μl.L-1时,亚油酸对东海原甲藻的抑制率超过80%。气相色谱-质谱联用(GC-MS)或高效液相色谱(HPLC)检测显示,凤眼莲根丙酮提取物中含有一定量的亚油酸和N-苯基-2-萘胺,同时还有大量的长链脂肪酸如十六酸、9-十六碳烯酸等。结果表明,凤眼莲根可显著抑制东海原甲藻的生长,N-苯基-2-萘胺、亚油酸可能是凤眼莲根抑藻的主要因子。 相似文献
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福建闽江水口水库凤眼莲空间分布特征及其动态 总被引：1，自引：1，他引：0
为研究闽江水口水库凤眼莲空间分布特征及动态变化,根据2001-2009年水口库区无云覆盖的24幅卫星遥感影像,构建研究区域凤眼莲干流-支流分布的空间结构,并通过建立端元的混合象元线性分解模型,对福建省水口水库不同时间、不同区域的凤眼莲分布特征进行系统分析,结果表明,随着时间的推移,凤眼莲的暴发区逐渐向下游迁移,同时,支流对研究区域凤眼莲的面积有重要影响,特别是河流较长、周边有人口居住的支流是凤眼莲源头治理的重点;各种人为或自然原因造成的水体富营养化、河流流速变缓等是凤眼莲泛滥的重要原因.建议针对研究区域上游及其周边进行养殖污染、工业污染整治,强化对污染源的监督管理,推进生态环境建设与保护,建设生态功能保护区等.本研究可为了解水口水库的凤眼莲时空分布规律,进而制定相应的预防与控制管理措施提供必不可少的数据基础和理论依据. 相似文献
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本文通过凤眼莲等水生植物对含银废水的净化与资源化的生产性应用试验,提出了工程实施的基本工艺,阐述了该工艺方案的特点和运行控制要求,分析了这一废水净化与资源化生态工程的环境效益和经济效益。这对我国感光材料工业和其它有关行业净化低浓度含银废水,并从中回收白银具有重要的意义。 相似文献
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喀斯特湿地水葫芦(Eichhornia crassipes)生长及表型可塑性特征对不同富营养化水体的响应 总被引：1，自引：0，他引：1
选择桂林会仙喀斯特湿地,以不同富营养化水体中生长时期为6月(生长旺盛期)和8月(暴发高峰期)的水葫芦(Eichhornia crassipes)为研究对象,探讨不同富营养化条件下水葫芦的生长及表型可塑性响应特征,以揭示水葫芦对不同富营养化水体的生态适应机制.结果表明:水葫芦的株高、根长和叶绿素含量均随水体富营养化程度的增加而降低,叶柄数、叶柄宽、叶片数、叶长、叶宽、匍匐茎数和分株速率随着水体富营养化程度的增加而升高;各性状参数在暴发高峰期均略高于生长旺盛期;根生物量、茎生物量、叶生物量和总生物量均随水体富营养化程度的加深而增加,茎生物量高于根生物量和叶生物量;水葫芦生物量的分配以及性状间的权衡关系(根生物量比、茎生物量比、叶生物量比和茎叶比等)因生长时期的不同而呈现差异性,表现出较强的表型可塑性特征;水体总有机碳、总氮、总磷、硝态氮、氨氮和叶绿素a浓度分别与水葫芦的茎生物量、叶宽、匍匐茎数和分株速率间存在显著的正相关关系,与根长、株高、叶生物量比和茎叶比间存在显著的负相关关系;水葫芦的表型可塑性指数在0.009~0.792之间,叶重比的可塑性指数最大,根冠比最小,重度富营养化水体下的可塑性指数最大.在会仙喀斯特湿地不同富营养化水体环境中,水葫芦通过外部形态结构调节和生物量的配比关系,产生了有利于其入侵和存活的较强的表型可塑性,是其生存繁殖的重要响应机制之一. 相似文献
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凤眼莲凋落物及其残体的沉降 总被引：6，自引：0，他引：6
水生植物凋落物和残体的沉降在水体生态系统物质循环和能鼍流动中具有重要作用,在有凤眼莲生长的自然水体中,利用沉降物捕获器原位采集凤眼莲生长、衰亡及腐烂分解等不同阶段的沉降物,分析测定其沉降量、沉降通量、有机碳、总氮和总磷的动态变化,结果显示:自凤眼莲死亡至残体从水面消失的4个月中,沉降瓶内的沉降量呈明显上升趋势,在残体从水面完全消失时(4月中旬)沉降量达到最大值579.59g/m2,同时,沉降通量亦达到最高值7.54g/(m2·d),二者与水温呈极显著正相关(P＜0.01);在凤眼莲生长期,沉降物的有机碳、总氮、总磷含量较低,而随着风眼莲衰亡,残体的不断沉降,至次年4月中旬残体基本沉降进入水体底部时,沉积物的有机碳、总氮、总磷含量达到最大值,分别为40.29%、3.66%、0.90%,之后逐渐下降,并趋于稳定. 相似文献
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植物根系在地球生物圈物质循环中起到关键性作用.陆生植物中目前基于根系具有对称性和自相似性假设建立的L系统已经做了较好研究,但在水生植物中相关的研究较少,更缺乏根系动态生长模型的构建.本文拟通过发展L系统来模拟水生植物从初生结构到次生结构,从简单根系到复合根系的动态生长过程.根系动态生长模型主要包含根系伸长规则和根系分支规则,并包含由主根与侧根的夹角θ和径向角γ确定初始根系生长方向.特别地,系统建立了2种代表性水生植物——世界上入侵严重的水生植物凤眼莲(Eichhornia crassipes)和被研究较多的水生植物穗状狐尾藻(Myriophyllum spicatum)根系动态生长模型.结果表明凤眼莲成熟根系总长度可达到2042.78 m,可能有利于其占据较多的空间和资源,使得凤眼莲在与本地植物的竞争中占有优势.穗状狐尾藻的总根系长度为73.08 m,由于穗状狐尾藻表现出最为典型的叉状分支构型,表明其对沉水生长环境有较好的适应性. 相似文献
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In situ hyperspectral reflectance data were studied at 50 bands (10 nm bandwidth) over the 400–900 nm spectral range to determine their potential for distinguishing among nine aquatic plant species: American lotus [Nelumbo lutea (Willd.) Pers.], American pondweed (Potamogeton nodusus Poir.), giant duckweed [Spirodela polyrrhiza (L.) Schleid.], Mexican waterlily (Nymphaea mexicana Zucc.), white waterlily (Nymphaea odorata Aiton), spatterdock [Nuphar lutea (L.) Sm.], giant salvinia (Salvinia molesta Mitchell), waterhyacinth [Eichhornia crassipes (Mart.) Solms] and waterlettuce (Pistia stratiotes L.). The species were studied on three dates: 30 May, 1 July and 3 August 2009. All nine species were studied in July and August, while only eight species were studied in May; giant duckweed was not studied in May due to insufficient availability. Two procedures were used to determine the optimum bands for discriminating among species: multiple comparison range tests and stepwise discriminant analysis. Multiple comparison range tests results for May showed that most separations among species occurred at bands 795–865 nm in the near-infrared (NIR) spectral region where up to six species could be distinguished. For July, few species could be distinguished amongthe 50 bands; most separations occurred at the 715 nm red-NIR edge band where four species could be differentiated. The optimum bands in August occurred in the green (525–595 nm), red (605–635 nm) and red-NIR edge (695–705 nm) spectral regions where up to six species could be distinguished. Stepwise discriminant analysis identified 11 bands in the blue, green, red-NIR edge and NIR spectral regions to be significant to discriminate among the eight species in May. For July and August, stepwise discriminant analysis identified 15bands and 13 bands, respectively, from the blue to NIR regions to be significant for discriminating among the nine species. 相似文献
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环太湖地区经济发达,人口密集,近年来面临严重的富营养化、生境退化和外来水生物种入侵等环境问题.为明确环太湖地区河道和湖泊沿岸带水生植物多样性现状,于2018年开展本地和外来水生植物多样性调查.结果表明:(1)在环太湖地区共计进行65个群落样方调查分析,记录到38种水生植物,分属22科29属;(2)环太湖地区31个河道样方中入侵沉水植物水盾草重要值最高,其次为另一种入侵漂浮植物凤眼蓝,在34个湖泊沿岸带样方中凤眼蓝重要值最高;(3)环太湖地区河道和湖泊沿岸带样方生物多样性分别随着水盾草和凤眼蓝盖度的增加而降低,表明外来入侵植物影响水生植物生物多样性.环太湖地区湖泊需加强防范凤眼蓝漂浮生长分布范围扩大和水盾草沿河道入侵太湖湖区.这一地区同时面对水生植物覆盖面积减少和外来植物入侵问题,建议进行全太湖流域水生植物分布区域和生物多样性摸底普查,加强对外来入侵植物传播的监控,建立水生植物自然保护区. 相似文献
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The dynamic model of physical-biological engineering for purifying water quality in Lake Taihu needs the parameter of sedimentation rate (SR). Especially, it is seldom reported how SR is influenced by interactions between algae and aquatic plant. So 6 enclosures with each area of 5×5 m2 were constructed in Wulihu with 2 m depth, a small hypereutrophic bay of Taihu Lake, China. Enclosures, in which the original water quality was the same as that in surrounding lake, were input Eichhomia crassipes at various original densities from 0-6 kg·m-2 on August 9, 1996. SR had been measured separately at depths of 0.6, 1.2f 1.8 m in each enclosure during 20 days. Main results were as follows:1) SR average in enclosures (17.3g·m-2 d-1) was as much as about 1/14 that in the surrounding lake; 2) The deeper was it, the higher rate was it in each enclosure, generally; 3) SR cures versus original densities of Eichhomia crassipes (ODE) in enclosures had the ship of "V" at different depths; SR minimuma were observed in the enclosure with original meso-density of Eichhomia crassipes (EMESO, 4kg·m-2), the average of SR minimuma was about 8.55 g ·m-2 d-1) SR in enclosures with original hypo-density (EHYPO, 0-3kg·m-2) were mainly negative related with water temperature and light intensity;while those with original hyperdensity (EHYPR, 5-6kg·m-2) were mainly negative related with transparency (SD) instead.These SR-distribution characteristics may be explained by interactions between dead algae and relics of Eichhomia crassipes. 相似文献
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