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1.
针对我国华南沿海特别是海南东寨港大面积红树林遭受团水虱(Sphaeroma sp.)为害,且目前尚无快速有效无污染、环境友好的团水虱防治方法,本研究提出了一种利用烟熏方法快速防治团水虱的技术。该技术采用两种烟剂混合,反应放热产生大量烟雾,通过神经毒和窒息作用快速(2 h以内)致死团水虱,从而实现红树林团水虱的快速有效防治,且环境友好、无污染。  相似文献   

2.
[目的]我国多地多次发生有孔团水虱(Sphaeroma terebrans)造成红树林死亡的事件。目前国内关于该团水虱的研究较少,国外有较长的研究历史但是研究时间和地点比较分散,通过借鉴前人的研究成果,以方便我们了解并防控该虫。[方法]查询中外文献、专利,并结合本人已开展的研究,主要针对有孔团水虱的形态、分布和分类、生物学特征、天敌,对红树林的危害特征和红树林对其的响应,以及目前的防治手段等方面着手进行总结。[结果]有孔团水虱分布范围很广,其形态特征存在地理性差异,基因研究表明有孔团水虱种群间不是一个单一物种而是一个复杂的分类群。国外有孔团水虱主要蛀孔于红树林气生根,国内除了气生根外还蛀孔于红树植物基干,且前者鲜有致死红树林的报道。对于蛀孔的生物学意义争议很大,既有可引起的"生态灾难",也有可给红树林带来的益处,但前者的支持者较多。团水虱一生至少蜕皮4次,两年可育3代。红树林气生根上团水虱空洞若数量较少,可自行愈合。有文献记录几种海洋生物可捕食团水虱,但天敌种类较少;国内已有关于团水虱的控制方法,但操作性差,且不能从根本上解决问题,仍需加强团水虱的防控相关研究,另外,开展团水虱灾害预警技术和灾后重建技术也迫在眉睫。  相似文献   

3.
团水虱对东寨港红树林的危害及防治对策   总被引:1,自引:0,他引:1  
近年来,团水虱大量繁殖引起东寨港红树林大面积死亡.文章描述了团水虱对红树林的危害,分析了团水虱繁殖泛滥的原因,提出了解决该问题的防治对策.  相似文献   

4.
海洋底栖生物团水虱(Sphaeroma sp.)于2010-2014年首次在我国红树林个别主要林区爆发成灾,引起了我国政府管理部门和学术界的极大关注,相关部门采取了一系列行动计划和相关防治研究等措施。从分布特点、生物学特性、爆发原因及其对红树林生境的危害等方面对我国的团水虱研究进行了综合分析,针对人为污染这一导致团水虱爆发的触发因子,就如何进一步提高我国团水虱治理效率提出了加强周边管理、建立监测机制以及多种防治方式相结合的几点建议。  相似文献   

5.
为预测团水虱的数量,减轻其对红树林植物的危害,采用多层感知器神经网络分析方法,对2021年3月至9月团水虱发生地的水温、风速、大气压、pH值、溶解氧、高锰酸盐指数、氨氮、总磷、总氮含量等因素进行分析。结果表明,总磷、水温是团水虱数量的主要因子,其拟合精度较好,平均绝对百分误差(MAPE)为0.120 2,均方误差(MSE)为85.486 1。使用该模型对2022年10月团水虱数量进行预测,其预测值为34.42/dm3,结果较为精确。  相似文献   

6.
我国红树林有害生物研究综述   总被引:5,自引:0,他引:5  
随着生态环境的破坏,大量有害生物侵入,给红树林造成严重威胁。红树林病害主要为真菌病害,如炭疽病、煤烟病以及锈病等;危害红树林的害虫种类多,危害重,主要是食叶性的蛾类,而且不断有新害虫出现,有严重危害广西红树林的可能;对于其它有害生物,螃蟹主要啃食幼苗,团水虱蛀干危害,藤壶虽不直接危害红树林,但因其在红树植物表面的附着性与营生性,影响了红树林的正常生长而成为危害红树林大面积的污染生物,也对红树林构成严重威胁。针对广西红树林有害生物防治中存在的问题,提出了解决办法。  相似文献   

7.
本文报道了红树林病原真菌8种,有害昆虫5种和海生生物2种及鸟类。论述了它们对红树林的为害程度和分布情况。对重要有害生物棉古毒蛾(OrgyiaposticaWalker)、红树林豹蠹蛾(Zeuzerasp.)、海生生物团水虱(Sphaeromasp.)、螃蟹及鸟类的发生特点、为害规律及与周围环境的关系进行了重点论述,并提出了初步的防治措施。  相似文献   

8.
东寨港红树林退化动态初步分析   总被引:1,自引:0,他引:1  
针对团水虱爆发导致海南东寨港红树林大面积退化的现象,对退化红树林群落的退化特征与林下土壤理化性质进行调查研究。结果表明:(1)相比2012年,2014年东寨港红树林退化程度加深,表现为:活立木株数明显减少、死亡率明显增高、群落郁闭度明显降低;(2)团水虱Sphaeroma sp.对红树林树种的蛀蚀具有选择性。长宁河沿岸不同红树树种退化程度不同,退化程度由重到轻依次为:木榄Bruguiera gymnorrhiza(26.47%)尖瓣海莲Bruguiera sexangula var.rhynchopetala(10.71%)海莲Bruguiera sexangula(10.42%)秋茄Kandelia candel红海榄Rhizophora stylosa;(3)退化红树林区域土壤沙粒含量2012年和2014年呈显著差异,2014年土壤沙粒含量比2012年显著减少;粘粒含量呈极显著差异,2014年土壤粘粒含量比2012年显著增加,而土壤粉粒含量和土壤容重则差异不显著。各样地土壤的化学性质包括p H值、速效钾含量在2012年和2014年呈现极显著差异,全盐量、碱解氮、有效磷呈显著差异,相比2012年,2014年土壤p H值、全盐量显著降低,土壤碱解氮、有效磷、速效钾显著增加。  相似文献   

9.
广州小斑螟Oligochroa cantonella Caradja是红树植物白骨壤Avicennia marina最主要食叶害虫之一。通过室内饲养和野外调查相结合方式对该虫进行形态学观察和生物学特性研究。以浸叶饲喂法和喷雾法对广州小斑螟进行7种药剂室内药效试验,3种药剂林间防治试验,并对灯光诱杀进行了研究。结果表明:广州小斑螟在广西红树林1 a发生6代,以低龄幼虫在白骨壤嫩芽内越冬。室内条件下棉铃虫核型多角体病毒对低龄幼虫致死率达100%,浸叶饲喂法较喷雾法效果好,林间试验采用棉铃虫核型多角体病毒、苦参碱和氯虫苯甲酰胺3种药剂防治,死亡率分别为90%,75%,30%;林间灯诱效果较好。  相似文献   

10.
<正>作为海陆交界处的特殊森林湿地生态系统,红树林在防风消浪、促淤保滩、固岸护堤、净化环境、维护生物多样性和沿海生态安全等方面发挥着重要作用。"红树林快速恢复与重建技术"项目针对红树林恢复重建中存在的主要问题,以红树林群落的快速形成为切入点,系统地研究并提出红树林快速恢复与重建的一系列关键技术及其评价指标体系。  相似文献   

11.
A dramatic decline in forest cover in eastern Africa along with a growing population means that timber and poles for building and fuelwood are in short supply. To overcome this shortage, the region is increasingly turning to eucalyptus. But eucalyptus raises environmental concerns of its own. Fears that it will deplete water supply, affect wildlife and reduce associated crop yields have caused many countries in the region to discourage farmers from planting this exotic. This paper is part of a series of investigations on the growth and water use efficiency of faster growing eucalyptus hybrids, which was introduced from South Africa to Kenya. The hypothesis is that the new hybrids are more efficient in using water and more suitable for the semi-arid tropics than existing eucalyptus and two popular agroforestry species. Gas exchange characteristics of juvenile Eucalyptus grandis (W. Hill ex Maiden), two eucalyptus hybrids (E. grandis × Eucalyptus camaldulensis Dehnh.), Grevillea robusta (A. Cunn) and Cordia africana (Lam) was studied under field and pot conditions using an infrared gas analyzer was used to measure photosynthetic active radiation (PAR), net photosynthetic rate (A), stomatal conductance (g s) and transpiration rate (E) at CO2 concentrations of 360 μmol mol−1 and ambient humidity and temperature. A, E and g s varied between species, being highest in eucalyptus hybrid GC 15 (24.6 μmol m−2 s−1) compared to eucalyptus hybrid GC 584 (21.0 μmol m−2 s−1), E. grandis (19.2 μmol m−2 s−1), C. africana (17.7 μmol m−2 s−1) and G. robusta (11.1 μmol m−2 s−1). C. africana exhibited high E values (7.0 mmol m−2 s−1) at optimal soil moisture contents than G. robusta (3.9 mmol m−2 s−1) and eucalyptus (5.3 mmol m−2 s−1) in field experiment and G. robusta (3.2 mmol m−2 s−1) and eucalyptus (4.2 mmol m−2 s−1) in pot-grown trees. At very low soil moisture content, extremely small g s values were recorded in GC 15 and E. grandis (8 mmol m−2 s−1) and G. robusta (14 mmol m−2 s−1) compared to GC 584 (46.9 mmol m−2 s−1) and C. africana (90.0 mmol m−2 s−1) indicating strong stomatal control by the species. Instantaneous water use efficiency ranged between 3 and 5 μmol mmol−1 and generally decreased with decline in soil moisture in pot-grown trees but increased with declining soil moisture in field-grown trees.  相似文献   

12.
Zusammenfassung Einige der wichtigsten gegenwärtigen Probleme hinsichtlich der landwirtschaftlichen Schädlinge in Finnland sind folgende:Bei Getreide die Schäden durchCalligypona pellucida am Hafer sowie die Schäden durch die Fritfliege(Oscinella frit) an Saat von Winter- und Sommergetreide, die durch Blasenfüßer(Thysanoptera) u. a. Arten verursachte Weißährigkeit und Schmachtkörnigkeit, deren Bekämpfung noch nicht befriedigend entschieden ist. — Beim RotkleePhytonomus nigrirostris, Apion apricans undA. assimile, Sitona spp. undDitylenchus dipsaci, deren Biologie und Bekämpfung weiterhin fortgesetzt werden, — Bei ÖlpflanzenCeuthorrhynchus assimilis undC. quadridens sowieDasyneura brassicae, deren Bekä mpfung zu ermitteln ist. — Bei Zuckerrübe sowie einigen anderen Kulturpflanzen Bedeutung und Bekä mpfung vonLygus-Arten (besondersL. rugulipennis undL. pratensis). Bekämpfung der Rübenfliege(Pegomyia hyoscyami) bei Zuckerrübenkulturen. — Bei den Wurzelschädlingen von Gemüse und Hackfrüchten Klären von Biologie und Bekämpfung der Kohlfliegen (Hylemyia brassicae undH. floralis), der Fliegenschädlinge von Zwiebeln (Hylemyia antiqua, Eumerus tuberculatus undE. strigatus) und der Möhrenfliege. — Die Wirkung der Spritzungen in Obstgärten auf die wichtigsten Schä dlinge(Metatetranychus pilosus, Doralina pomi, Psylla mali, Carpocapsa pomonella, Argyresthia conjugella) und ihre wirksamsten Feinde.— In Beerengärten bei den ArtenTarsonemus fragariae, Eriophyes ribis undPachynematus pumilio sowie in Obstgärten bei der ArtAnisandrus dispar Intensivierung der Bekä mpfung. — Älchen(Anguillulidae), besondersdas Kleeälchen und Klärung von Lebensbedingungen und Bekämpfung desKartoffelälchens. — Bedeutung und Bekämpfung der Wühlmäuse (besondersMicrotus agrestis, M. arvalis undArvicola terrestris). — Untersuchung der Bedeutung von virusverbreitenden Insektenarten. — Erforschung der Nachteile von Bekämpfungsmitteln für die Pflanzen.  相似文献   

13.
重庆酸雨区缙云山典型林分冠层酸雨淋洗特征   总被引:2,自引:1,他引:2       下载免费PDF全文
选取重庆缙云山的针阔混交林、常绿阔叶林、毛竹林、灌木林4种典型林分,观测酸性降水过程中林外雨、穿透雨及干流等林内水分转换分量中的主要离子含量变化,分析林分冠层对雨水化学组成的影响,结果表明:(1)降雨中的离子当量浓度大小依次是SO42->Ca2+> NH4+>Mg2+>K+>Na+>NO3-;(2)降雨经过林冠层后pH值降低,干流的酸化程度增加最大;(3)降雨经林冠层后离子浓度明显增加(除灌木林),穿透雨中通量增加最大的阴离子和阳离子分别为SO42-(2.19×103~6.47×103 eq·hm-2)和Ca2+(1.41×103~3.39×103 eq-hm-2),离子来源主要为大气沉降和植物分泌物或淋出;(4)同一离子在不同林分的干流和穿透雨中的通量变化不同,反映出不同林分冠层的离子交换性差异.在针阔混交林中,林下降雨净淋溶量大小顺序为SO42->Ca2+> NO3->K+>NH4+>Mg2+> Na+;常绿阔叶林为SO42-> Ca2+> K+>NO3-> NH4+> Mg2+ >Na+;毛竹林为Ca2+> SO42-> K+>NO3-> NH4+>Na+>Mg2+;灌木林为Ca2+> NO3-> K+> Na+>Mg2+> NH4+> SO42-.  相似文献   

14.
广州市酸雨对不同森林冠层淋溶规律的研究   总被引:20,自引:2,他引:20       下载免费PDF全文
1998年4月至1999年3月对广州市白云山马尾松林和常绿阔叶林、广州市龙眼洞马尾松林两试验点进行了酸雨的监测,并测定和分析了林内穿透雨物理量及化学量,旨在探讨酸雨对不同森林冠层养分淋溶规律的影响。结果表明:(1)广州市酸雨占次数的79.7%或占降雨量的95.1%。(2)酸雨通过林冠层后,pH值明显增加。(3)在马尾松林和常绿阔叶林中,某些单次降雨出现SO4^2-、NO3^-、NH4^+Al^3+、Na^+的负淋溶现象,说明森林对这些离子(特别是NO3^-、Aa^3+)具有吸收作用;阔叶林全年的NO3^-和Al^3+净淋溶为负值,说明阔叶林比马尾松林对这两种离子具有更强的吸收能力。(4)雨水酸度增加(即pH值减小),明显提高阳离子Ca^2+、Mg^2+、K^+和Na^+冠层淋溶面分率。(5)NH4^+、SO4^  相似文献   

15.
A typhoon event catastrophically destroyed a 45-year-old Japanese larch plantation in southern Hokkaido, northern Japan in September 2004, and about 90% of trees were blown down. Vegetation was measured to investigate its regeneration process and CO2 flux, or net ecosystem production (NEP), was measured in 2006–2008 using an automated chamber system to investigate the effects of typhoon disturbance on the ecosystem carbon balance. Annual maximum aboveground biomass (AGB) increased from 2.7 Mg ha−1 in 2006 to 4.0 Mg ha−1 in 2007, whereas no change occurred in annual maximum leaf area index (LAI), which was 3.7 m2 m−2 in 2006 and 3.9 m2 m−2 in 2007. Red raspberry (Rubus idaeus) had become dominant within 2 years after the typhoon disturbance, and came to account for about 60% and 50% of AGB and LAI, respectively. In comparison with CO2 fluxes measured by the eddy covariance technique in 2001–2003, for 4.5 months during the growing season, the sum of gross primary production (GPP) decreased on average by 739 gC m−2 (64%) after the disturbance, whereas ecosystem respiration (RE) decreased by 501 gC m−2 (51%). As a result, NEP decreased from 159 ± 57 gC m−2 to −80 ± 30 gC m−2, which shows that the ecosystem shifted from a carbon sink to a source. Seasonal variation in RE was strongly correlated to soil temperature. The interannual variation in the seasonal trend of RE was small. Light-saturated GPP (Pmax) decreased from 30–45 μmol m−2 s−1 to 8–12 μmol m−2 s−1 during the summer season through the disturbance because of large reduction in LAI.  相似文献   

16.
Dissolved inorganic nitrogen (DIN) (as ammonium nitrate) was applied monthly onto the forest floor of one old-growth forest (>400 years old, at levels of 50, 100 and 150 kg N ha−1 yr−1) and two young forests (both about 70 years old, at levels of 50 and 100 kg N ha−1 yr−1) over 3 years (2004–2006), to investigate how nitrogen (N) input influenced N leaching output, and if there were differences in N retention between the old-growth and the young forests in the subtropical monsoon region of southern China. The ambient throughfall inputs were 23–27 kg N ha−1 yr−1 in the young forests and 29–35 kg N ha−1 yr−1 in the old-growth forest. In the control plots without experimental N addition, a net N retention was observed in the young forests (on average 6–11 kg N ha−1 yr−1), but a net N loss occurred in the old-growth forest (−13 kg N ha−1 yr−1). Experimental N addition immediately increased DIN leaching in all three forests, with 25–66% of added N leached over the 3-year experiment. At the lowest level of N addition (50 kg N ha−1 yr−1), the percentage N loss was higher in the old-growth forest (66% of added N) than in the two young forests (38% and 26%). However, at higher levels of N addition (100 and 150 kg N ha−1 yr−1), the old-growth forest exhibited similar N losses (25–43%) to those in the young forests (28–43%). These results indicate that N retention is largely determined by the forest successional stages and the levels of N addition. Compared to most temperate forests studied in Europe and North America, N leaching loss in these seasonal monsoon subtropical forests occurred mainly in the rainy growing season, with measured N loss in leaching substantially higher under both ambient deposition and experimental N additions.  相似文献   

17.
Five new ursane-type triterpenoidal saponins (15), together with five known ones (610), were isolated from the EtOH extract of the roots of Ilex cornuta. The structures of saponins 15 were elucidated as 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside (1), 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside-6-O-ethyl ester (2), 19α-hydroxyurs-12-en-28-oic acid 3β-O-α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranoside (3), 3β-O-[α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranosyl]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (4) and 3β-O-[α-L-arabinopyranosyl-(1  2)-β-D-glucuronopyranoside-6-O-methyl ester]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (5), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 110 against H2O2-induced H9c2 cardiomyocyte injury were tested. Compounds 15, 7, and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 110.  相似文献   

18.
A new canker disease of Salix alba and Populus alba has been observed in Xinjiang, China. Black circular spots on dead branches and stems are the symptoms of the disease. Sixty‐seven isolates recovered from Salix matsudana, S. alba and Populus alba were identified as Cryptosphaeria pullmanensis based on morphological features and multigene phylogeny. Pathogenicity tests were performed on S. alba and P. alba stems using the C. pullmanensis isolates. Cankers on and Cryptosphaeria pullmanensis of C. pullmanensis from the stems fulfilled Koch's postulates and confirmed C. pullmanensis as the causal agent of the canker disease. C. pullmanensis is characterized by its yellow stromatic tissue surrounded by a black conceptacle with regularly arranged multiple locules sharing common walls and hyaline, allantoid, aseptate conidia (mean size 7.42 × 1.72 μm). This is the first report of C. pullmanensis causing Cryptosphaeria canker in China, and S. alba and P. alba are new host records for C. pullmanensis.  相似文献   

19.
This study was conducted to determine carbon (C) dynamics following forest tending works (FTW) which are one of the most important forest management activities conducted by Korean forest police and managers. We measured organic C storage (above- and below-ground biomass C, forest floor C, and soil C at 50 cm depth), soil environmental factors (soil CO2 efflux, soil temperature, soil water content, soil pH, and soil organic C concentration), and organic C input and output (litterfall and litter decomposition rates) for one year in FTW and non-FTW (control) stands of approximately 40-year-old red pine (Pinus densiflora S. et Z.) forests in the Hwangmaesan Soopkakkugi model forest in Sancheonggun, Gyeongsangnam-do, Korea. This forest was thinned in 2005 as a representative FTW practice. The total C stored in tree biomass was significantly lower (P < 0.05) in the FTW stand (40.17 Mg C ha−1) than in the control stand (64.52 Mg C ha−1). However, C storage of forest floor and soil layers measured at four different depths was not changed by FTW, except for that at the surface soil depth (0–10 cm). The organic C input due to litterfall and output due to needle litter decomposition were both significantly lower in the FTW stand than in the control stand (2.02 Mg C ha−1 year−1 vs. 2.80 Mg C ha−1 year−1 and 308 g C kg−1 year−1 vs. 364 g C kg−1 year−1, respectively, both P < 0.05). Soil environmental factors were significantly affected (P < 0.05) by FTW, except for soil CO2 efflux rates and organic C concentration at soil depth of 0–20 cm. The mean annual soil CO2 efflux rates were the same in the FTW (0.24 g CO2 m−2 h−1) and control (0.24 g CO2 m−2 h−1) stands despite monthly variations of soil CO2 efflux over the one-year study period. The mean soil organic C concentration at a soil depth of 0–20 cm was lower in the FTW stand (81.3 g kg−1) than in the control stand (86.4 g kg−1) but the difference was not significant (P > 0.05). In contrast, the mean soil temperature was significantly higher, the mean soil water content was significantly lower, and the soil pH was significantly higher in the FTW stand than in the control stand (10.34 °C vs. 8.98 °C, 48.2% vs. 56.4%, and pH 4.83 vs. pH 4.60, respectively, all P < 0.05). These results indicated that FTW can influence tree biomass C dynamics, organic C input and output, and soil environmental factors such as soil temperature, soil water content and soil pH, while soil C dynamics such as soil CO2 efflux rates and soil organic C concentration were little affected by FTW in a red pine stand.  相似文献   

20.
Zusammenfassung Es konnten 132Bacillus-Stämme isoliert und gegenüber7 Rhizoctonia-solani- und 6Pythium-Stämmen auf Antagonismusin vitro untersucht werden. Die gefundenen Antagonisten hemmten die Pilzisolate unterschiedlich stark, so daß Gemische von Antagonisten für die Praxis zu empfehlen sind.
Antagonismin vitro ofBacillus spp. againstRhizoctonia solani andPythium spp.
There were 132Bacillus-strains isolated and tested for antagonism against 7 strains ofRhizoctonia solani and 6 strains ofPythium spp. The isolated antagonists didn't show a uniform effect against the tested strains ofRhizoctonia solani andPythium spp. For an application in practice it will be better to use a mixture of antagonists.


Mit 4 Abbildungen und einer Tabelle  相似文献   

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