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161.
外秦淮河生态护坡挺水植物适应性试验研究 总被引:3,自引:0,他引:3
针对外秦淮河的污染状况,采用挺水植物菖蒲和狭叶香蒲进行试验,对外秦淮河的污染水质进行净化;同时进行两种挺水植物在外秦淮河当前水质下的耐淹没性试验.通过试验研究得出,在深秋季节,虽然菖蒲和狭叶香蒲两种植物已经处于生长周期的最后阶段,但是对外秦淮河污染水质仍然有较好的净化效果,对TP、TN、氨氮等的去除率能达到80%以上,对CODMn的去除率偏低.而且通过净化和耐淹试验中两种植物的对比,菖蒲比狭叶香蒲更能适应外秦淮河的水质状况. 相似文献
162.
IntroductionTheScheldeRiveroriginatesinSaint Quentin(NorthernFrance) ,passesthroughBelgiumandtheNetherlandsandthenflowsintotheNorthSeainVlissingen .ItistheonlytrueestuaryleftintheDeltaarea(Herman ,1999) .TheBelgiangovernmentapprovedtheso calledSIGMAplanfollow… 相似文献
163.
Effectsofsulfurdioxideongrowth,gasexchangerateandleafsulfurcontentofmassionpineseedlingsYangLiangUnitedGraduateSchool,TokyoUn... 相似文献
164.
Freddie-Jeanne?RichardEmail author Abraham?Hefetz Jean-Philippe?Christides Christine?Errard 《Chemoecology》2004,14(1):9-16
Summary. Neotropical Fungus-growing leaf-cutting ants (tribe Attini) live in
obligatory symbiosis with a fungus, which they grow on fresh leaves harvested by
workers. Colonial recognition is likely based on chemical cues provided by cuticular
hydrocarbons that have been found to be partly influenced by environmental odor
sources. The diet breadth of Acromyrmex
subterraneus subterraneus enabled us to test
the impact of different plant diets on colonial recognition. The intermediary of the
fungus in the ants feeding habit adds a special angle to the question.
From a queenright (QR) mother colony of A. s. subterraneus
we formed several groups of queenless (QL) workers with fungus (approx. 700 ants). The QR
colony and two of the QL-groups were fed with the same diet of fresh bramble leaves. Two other
QL-groups were fed with privet leaves and two with rose flowers. After 4 months, QR workers were
significantly more aggressive towards the QL-group fed with rose flowers or privet
leaves than towards workers of the QL-groups fed with fresh bramble leaves. Rose-fed
QL workers were aggressive towards privet-fed QL workers and vice versa, but never towards
workers of their counterpart group that fed on the same diet. These results suggest
that the absence of the queen or the separation time between groups played a minor
role in shaping nestmate recognition cues as compared to the diet. The behavioral
studies were supplemented by chemical analyses of cuticles, postpharyngeal glands
(PPG) and plant-food extracts revealing profiles variations that were correlated
with the dietary changes. However, although the plant extract contained several
hydrocarbons there was no congruency between the plant profile and the respective
diet-group ants. These results support the hypothesis that the diet influences
indirectly the chemical profiles and consequently the recognition cues in
A. s. subterraneus. 相似文献
165.
广州白云山风景区阔叶植物叶片中的多环芳烃 总被引:1,自引:0,他引:1
多环芳烃(PAHs)在环境中分布极广,作为持久性亲脂有机污染物,具有很强的生物累积性。植物对周围环境有着高度的依赖性,阔叶植物由于叶面巨大的表面积,容易吸收富集环境中的多环芳烃。采集了白云山9种阔叶植物叶片样品,利用GC-MS对样品中的多环芳烃进行了定量分析。结果表明,白云山阔叶植物叶片样品中的PAHs以芘所占比例最高,总PAHs为460.2~1303.5ng·g-1(干质量)。从组成上看,白云山阔叶植物叶片中多环芳烃以3环、4环为主,比较发现这种组成特征与大气中PAHs相似。运用分子标志物比值法分析PAHs的来源,发现阔叶植物样品中PAHs主要是热成因来源。广州市工业发达,环境中含有较高PAHs在白云山阔叶植物叶片中已有明显的反映,应加强对环境中PAHs监控和治理。 相似文献
166.
梅树经氟化氢熏气后,离区纤维素酶活力升高,这可能是某些植物受大气氟污染后产生非正常落叶的原因。熏气前喷洒生长调节物质,可以相对降低纤维素酶活力,有效地抑制大气氟污染产生的落叶效应。 相似文献
167.
Thomas?HartmannEmail author H?kan?H?ggstr?m Claudine?Theuring Rainer?Lindigkeit Martine?Rahier 《Chemoecology》2003,13(3):123-127
Summary. The harvestman Mitopus morio (Phalangidae) is
a generalist predator. It is known to prey on larvae of the
chrysomelid leaf beetle Oreina cacaliae defended by plant
acquired pyrrolizidine alkaloids (PAs). Tracer feeding
experiments were performed to determine how harvestmen
tolerate protoxic PAs. Minced meat containing either
[14C]senecionine or [14C]senecionine N-oxide was fed to
M. morio and subsequently feces and bodies were analyzed.
Labeled alkaloid N-oxide remained stable and was eliminated
almost unaltered with the feces; only 10% was recovered
as tertiary PA. In contrast, approximately 80% of
labeled tertiary alkaloid (senecionine) ingested with the diet
was N-oxidized and eliminated; the remaining 20% consisted
of unchanged senecionine and a polar metabolite
of unknown structure. Harvestmen process their diet by
excreting digestive juice, indicated by bleaching of the meat
color. Analysis of the processed diet revealed some N-oxidation
of [14C]senecionine, suggesting the gut as the site of Noxidation.
Analysis of the bodies of harvestmen 80 hours
after the tracer feeding pulse revealed only trace amounts of
the polar metabolite. Neither senecionine nor its N-oxide
could be detected in the body extracts. The results are discussed
in relation to the strategies of PA adapted insects to
avoid accumulation of tertiary PAs in living tissues. 相似文献
168.
Kentaro Hayashi Takeshi TokidaToshihiro Hasegawa 《Agriculture, ecosystems & environment》2011,144(1):117-123
The present study aimed to investigate the potential ammonia (NH3) emission from flag leaves of paddy rice (Oryza sativa L. cv. Koshihikari). The study was conducted at a paddy field in central Japan that was designed as a free-air CO2 enrichment (FACE) facility for paddy rice. A dynamic chamber method was used to measure the potential NH3 emissions. The air concentrations of NH3 at two heights (2 and 6 m from the ground surface) were measured using a filter-pack method, and the exchange fluxes of NH3 of the whole paddy field were calculated using a gradient method. The flag leaves showed potential NH3 emissions of 25-38 ng N cm−2 h−1 in the daytime from the heading to the maturity stages, and they showed potentials of approximately 22 ng N cm−2 h−1, even in the nighttime, at the heading and mid-ripening stages. The exchange fluxes of NH3 of the whole paddy field in the daytime were net emissions of 0.9-3.9 g N ha−1 h−1 whereas the exchange fluxes of NH3 in the nighttime were approximately zero. 相似文献
169.
Megat Hanafiah Megat Ahmad Kamal Wan Mat Khalir Wan Khaima Azira Mohamed Kasmawati Zakaria Haslizaidi Wan Ngah Wan Saime 《环境科学学报(英文版)》2010,22(2)
Rubber leaf powder(an agricultural waste) was treated with potassium permanganate followed by sodium carbonate and its performance in the removal of Pb(Ⅱ) ions from aqueous solution was evaluated.The interactions between Pb(Ⅱ) ions and functional groups on the adsorbent surface were confirmed by Fourier transform infrared(FT-IR) spectroscopy,scanning electron microscopy(SEM) coupled with X-ray energy dispersive spectroscopy(EDX).The effects of several important parameters which can affect adsorption capacity such as pH,adsorbent dosage,initial lead concentration and contact time were studied.The optimum pH range for lead adsorption was 4-5.Even at very low adsorbent dosage of 0.02 g,almost 100% of Pb(Ⅱ) ions(23 mg/L) could be removed.The adsorption capacity was also dependent on lead concentration and contact time,and relatively a short period of time(60-90 min) was required to reach equilibrium.The equilibrium data were analyzed with Langmuir,Freundlich and Dubinin-Radushkevich isotherms.Based on Langmuir model,the maximum adsorption capacity of lead was 95.3 mg/g.Three kinetic models including pseudo first-order,pseudo second-order and Boyd were used to analyze the lead adsorption process,and the results showed that the pseudo second-order fitted well with correlation coefficients greater than 0.99. 相似文献
170.
应用火焰原子吸收光谱法,对长春市14条主要街路交通密集地段两侧绿化带中采集到的12种代表性植物叶片的铅含量进行了分析。结果表明,植物叶片的铅含量范围在8.20 mg/kg~58.5 mg/kg之间,平均值为19.7 mg/kg。木本植物叶片的平均铅富集能力略低于草本植物,并且木本植物叶片平均铅含量的空间变异性较大;木本植物中杨树叶片的平均铅富集能力最强而榆树最低,草本植物中绣线菊的叶片平均铅富集能力最强而八宝景天最低;草本植物中绣线菊的叶片在所有供试植物叶片中平均铅富集能力最强,其次为木本植物中杨树的叶片,而草本植物中八宝景天的叶片平均铅富集能力最低。不同植物在同一街路以及同种植物在不同街路之间其叶片的铅含量都不同。 相似文献