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1.
内蒙古中南部轮藻植物以温带成分占绝对优势,有较多的中国特有植物;种类以轮藻属为主,其中丛刺轮藻、灰色轮藻为本地的广布和优势种;分布以上河套平原的种类、数量最多;另外,轮藻植物的形态结构、种类组成及分布均与其生长的环境紧密相关。  相似文献   

2.
欧洲东南部巴尔干轮藻植物由于其产地生境的差异及以镶嵌状分布的模式,具有较高的生物分异度,计有44种,归属于现生属Nitella(10),Tolypella(4),Nitellopsis(1),Lychnothamnus(1),Lamprothamnium(1) and Chara(27).巴尔干半岛产有4种土著类型Chara rohlenae,Chara ohridana,Chara corfuensis and Chara visianii.建立1新种Chara hydropitys.该地区轮藻植物分布不均衡,部分类型例如Chara strigosa,Chara kokeilii,Chara muscosa,Chara fragifera,Chara imperfecta,Lychnothamnus barbatus为稀有品种,仅在少数地点发现.巴尔干地区轮藻植物之丰富多彩远远超过已知的程度,有待于深入研究.  相似文献   

3.
迷迭香幼芽诱导产生的愈伤组织转移至B5培养基中,振荡培养3d后进入对数生长期。每g细胞约增加5g多。最适植物生长调节物质量为:NAA0.25mg/L、2,4-D1mg/L、KT0.5mg/L。此种细胞也能产生类似于原植物的挥发油,其组分主要有十六烷酸、2,6-二异丁基-4-甲基苯酚、樟脑、桉油精以及在原植物中未曾发现的柳杉烯。  相似文献   

4.
1mg/mL KCl促进荷叶离褶伞菌丝生长;5或10mg/mL NaCl、5或10mg/mL MgSO4、5或10mg/mLKCl、10mg/mL H2PO4和1mg/mL CaSO4抑制菌丝生长;0.8mg/mL的MnSO4和CuSO4以及0.5mg/mL FeSO4、0.2或0.5mg/mL CoCl2和0.2、0.5或0.8mg/mL ZnSO4促进菌丝生长;0.5或0.2mg/mL CuSO4、0.2或0.5mg/mL MnSO4及0.8或0.2mg/mL FeSO4对菌丝生长的影响不显著;维生素B6、维生素C、维生素PP和维生素B1可促进菌丝生长,在含有10μg/L维生素B6的培养基上菌丝生长速度最快,但维生素C试用浓度较低(50μg/L)时对菌丝生长的影响不显著;吲哚丁酸、吲哚乙酸、奈乙酸对菌丝生长具有促进作用,但0.1、0.5或1.0μg/L赤霉素对菌丝生长的影响不显著。  相似文献   

5.
一种用于盐度测量的光纤传感器   总被引:3,自引:0,他引:3  
制作了智能水凝胶PDA—C12。根据凝胶的溶胀性质设计制作了一种盐度光纤传感器探头,并实测了在不同盐度溶液中的输出光强,可测范围达到了1.0mol/L以上,为在一般要求下的盐度测量提供了一种新的方法。  相似文献   

6.
日本茄F1离体快速繁殖   总被引:3,自引:0,他引:3  
R8pidPfopsgstiollofEggplslltFIIrtMtTOCHENLi-Pin,CHENZhu-Jung,DONGWeiMin(几W训MOfHonk?1’LI;,7w,出。山wApe2,7YllUn。吻,H哗哗m310029)1植物名称茄(Sdri肌_),来源于日本的杂交1代(F;),松岛制种。2材料类别无菌种子苗的茎尖和带芽茎段。z培养条件培养基:(川/ZMS;Q)Ms+KTI~7mg/L(单位下同);(3)MS+6-BAI~7;(4)l/2MSuNAA0.l。以上培养基均加蔗糖30g/L,琼脂8g/L,PH值为5.8左右。高压灭菌,培养温度23~26C,光照12h/d,光照度1000IX左右。4生长与分化情况4.1…  相似文献   

7.
高效液相色谱法测定蒲公英提取物中咖啡酸含量   总被引:2,自引:0,他引:2  
建立了一种高效液相色谱法测定蒲公英提取物中咖啡酸的含量。色谱柱为Diamonsil^TM(钻石)C18(4.6mm×150mm,5μm),流动相为甲醇-磷酸盐缓冲液(1.56g磷酸二氢钠/1000mL水,磷酸调节pH值3.8—4.0)(体积比为23:77);检测波长为323nm,柱温为40℃。研究结果表明:线性范围为2.44—14.64mg/L,回归方程为y=41742x+2287.9相关系数为R^2=0.9996,加标平均回收率为97.5%。本方法具有灵敏度高、重现性好、准确度高、操作简便等特点。  相似文献   

8.
盐度和温度对中华虎头蟹(Orithyia sinica) 存活和摄饵的影响   总被引:9,自引:0,他引:9  
廖永岩  吴蕾  蔡凯  潘传豪 《生态学报》2007,27(2):627-639
进行盐度和温度对中华虎头蟹存活和摄饵影响的试验,结果发现,盐度骤变时,盐度15—408d后蟹存活率100%。盐度10—45蟹能摄饵,日平均摄饵量达1.31g以上;盐度20—40是蟹适宜摄饵盐度,日平均摄饵量达3.65g以上;盐度30—35蟹摄饵最佳,日平均摄饵量达5.24g以上。盐度渐变时,盐度15—55蟹8d后存活100%;盐度5—50蟹能摄饵;盐度25—35为蟹摄饵适宜盐度,日平均摄饵量达4.13g以上;盐度30为最佳盐度,日平均摄饵量达4.53g。温度骤变时,10—30℃7d后蟹100%存活。10—35℃蟹能摄饵,日平均摄饵量达1.10g以上;20—30℃蟹摄饵最佳,日平均摄饵量逐渐增加,达8.76g以上。温度渐变时,0—30℃蟹7d后100%存活,35℃蟹存活率达80%。10—35℃蟹能摄饵;20—30℃蟹摄饵较佳,日平均摄饵量达12.61g以上;250C蟹摄饵最佳,13平均摄饵量达14.35g。  相似文献   

9.
氮饥饿补糖分批培养小克银汉霉产γ-亚麻酸的研究   总被引:3,自引:0,他引:3  
对小克银汉霉C2(Cunninghamella sp.C2)发酵生产γ-亚麻酸工艺进行研究,发现氮饥饿补糖能有效地积累γ-亚麻酸,在第5、6、7d每天补糖15g/L,培养10d后生物量、油脂和γ-亚麻酸的产量分别达到47.4g/L、19.74g/L和1.86g/L,为分批培养的2.85、2.08和2.07倍。  相似文献   

10.
环境条件及摇瓶补糖策略对谷胱甘肽发酵的影响   总被引:19,自引:1,他引:18  
研究了酵母摇瓶发酵中pH、装液量、初糖浓度、碳氮磷比和补糖方式对谷胱甘肽(GSH)发酵的影响。结果表明,GSH发酵适宜的初始pH和装液量分别为6 0和500ml锥形瓶内装液量60m1。初糖浓度对GSH发酵有较大的影响,超过12g/l,的初糖浓度将减少胞内GSH含量。应用计算得出的一种以控制比生长速率为目的的摇瓶补糖策略,在总糖浓度为26.2g/L下发酵12h,最终细胞浓度和胞内GSH含量分别达到8.78g/L和13.6mg/g,发酵液内GSH总量达到119.4mg/L,细胞对糖产率达到0.335g/g。  相似文献   

11.
娘子关泉域藻类植物的初步研究   总被引:11,自引:0,他引:11  
1984~2000年间,对娘子关泉域的藻类植物进行了15次采集,共采得藻类植物标本200余号。经鉴定,有107种,隶属7门,32科,49属。其中,以绿藻门的种类最多,有13科,19属,45种。其次是裸藻门,有2科,7属,26种。排在最后的是轮藻门,有1科,1属,3种。群落主要包括8类,即刚毛藻-红毛菜群落(Cladophora Bangia community),刚毛藻群落(Cladophora community),拖拉藻-轮藻群落(Chara Thorea community),弯枝藻-拖拉藻群落(Composopogon-Thorea community),水绵-双星藻群落(Spirogyra Zygnema community),无隔藻群落(Vaucheria community),串珠藻群落(Batrachospermum community)和泡状饶氏藻群落(Jaoa community)。其中,有的群落类型已趋于消失或消失,许多种类已成为濒危物种,其原因主要是人为因素造成藻类植物生存环境的改变或破坏。本文也提出了相应的保护对策。  相似文献   

12.
Based on the perennial monitoring (1995–2010) of hyperhaline water reservoirs in the south of Western Siberia with salinity from 28 to 417 g/L, four seasons in the development of biocoenoses are distinguished and integrated results of studies of the effect of environmental factors on the species composition and productivity of biocoenoses are presented. The decisive role of temperature on the seasonal cycles of hydrocole development and salinity on the productivity and composition of biocoenoses are revealed. The highest species diversity is observed in summer at temperatures above 12°C; the fauna is represented only by artemia cysts at negative temperatures. With an increase of salinity from 28 to 100 g/L the number of species declines. For salinity 100 g/L the fauna is represented only by brine shrimp Artemia. Hyperhaline biocoenoses are the most productive at salinity 150–180 g/L.  相似文献   

13.
The effects of increased salinity on plant growth were examined in a greenhouse experiment with four species common to oligohaline marshes of the northern Gulf of Mexico: Eleocharis palustris, Panicum hemitomon, Sagittaria lancifolia, and Scirpus americanus. Effects of final salinity reached (6 or 12 g/L), salinity influx rate (3 d or 3 wk), and duration of exposure (1, 2, or 3 mo) were investigated. Sagittaria lancifolia was the first species to show visible signs of stress, with browning and curling of older leaf edges. The salt effect was delayed for 6-8 wk in P. hemitomon, but this species had the highest aboveground tissue mortality rate at 12 g/L as exposure continued. Final salt concentration affected all species to a greater degree than did salinity influx rate. No aboveground mortality occurred at 6 g/L, but growth suppression was apparent and varied with species. The magnitude of growth suppression in response to salinity increased for all species as the duration of exposure increased. Overall, we ranked the species as follows, in order from least to most salt tolerant: Panicum hemitomon < Sagittaria lancifolia < Eleocharis palustris < Scirpus americanus. This ranking reflects the field occurrence of these species along a gradient of increasing salinity in northern Gulf of Mexico coastal habitats from freshwater wetlands through oligohaline areas to mesohaline wetlands.  相似文献   

14.
The combined effect of salinity and temperature on Spirorbis spirorbis L. and Circeus spirillum L. larvae from the White Sea was studied in the laboratory experiments. In the White Sea, S. spirorbis is distributed through the depth of 1-20 m and is affected by all varieties of fluctuations in salinity and temperature. C. spirillum lives in more wide range of depths 1-55 m and is more stenohaline. S. spirorbis larvae are sufficiently more resistant to the low salinity (10‰) than C. spirillum larvae. Both species are stenothermic. Highest survivorship of S. spirorbis larvae was marked under 5 °C in all experimental salinities. Under temperature treatments of 10-15 °C, the larval survivorship was sufficiently restricted in all salinities. Highest survivorship of C. spirillum larvae was also marked under 5 °C but in more narrow salinity range.The number of larvae undergoing metamorphosis in both species was very low, only about 10% of the total number. Highest number of successful attachments in both species was marked in high salinities (25-30‰) and does not exceed 25% of survivors. Experimental data suggests that salinity and temperature affect directly general survivorship of the larvae and secondary-attachment and metamorphosis processes.  相似文献   

15.
This study analyses the complicated patterns of vertical distribution of the macroalgal vegetation in an area where brackish and marine waters meet and mix. Variables used to record vegetation characteristics are algal cover, species composition and diversity. The data set includes 64 diving profiles, all from sites exposed to wave action, along a ca. 260 km long coastline. The profiles belong to four categories: coastal sites in the Skagerrak (more marine), coastal sites in the Kattegat (more brackish), coastal sites in the Kattegat after a toxic phytoplankton bloom, and submerged offshore stone reefs in the Kattegat. The highest species diversity was found at the reefs, which are not affected directly by land runoff. At the reefs the 18 most common perennial species penetrate 2–11 m (on average 5.5 m) deeper than at the coastal sites. The virtual absence of sedimentation, and thus the availability of substratum, at the reefs may explain the differences so that the lower limit for the algae is determined by light penetration or by recruitment problems caused by strong currents at the reefs, whereas sedimentation limits the settlement of algae in coastal sites. Ordination analysis based on species composition reveals that the major environmental gradients structuring the algal vegetation in the Kattegat and the Skagerrak are salinity and water depth. The large data set of this study made it possible to quantify the downward dislocation of Atlantic intertidal species to the sublittoral along the Swedish west coast. For example, the mean upper limit of Corallina officinalis is 2 m in the Skagerrak but 12.5 m in the Kattegat and the mean occurrence interval of Fucus serratus is 0.9–2.7 m in the Skagerrak, but 1.1–6.3 m in the Kattegat. This downward dislocation is suggested to be the result of decreased competition when species successively disappear with lower salinity. Comparisons of the present study's results with those of previous investigations show that eight common red algal species have moved upwards compared to the situation before the large-scale eutrophication started in the 1960s, e.g. Cystoclonium purpureum and Polysiphonia elongata by ca. 8 m, Phycodrys rubens and Delesseria sanguinea by ca. 5 m. A toxic phytoplankton bloom affected macroalgal community composition on the whole only slightly, but it had a negative effect on algal cover and species richness below a water depth of ca. 5 m, the algae were visibly damaged and the lower vegetation limit temporarily moved upwards.  相似文献   

16.
白鹤湖作为莫莫格湿地保护区内的代表性湖泊, 正面临着盐碱化和富营养化的风险, 现存沉水植物种类稀少, 为了减缓白鹤湖盐碱化趋势, 为当地沉水植被恢复及物种多样化存续提供研究依据, 以在白鹤湖生物量相对大的金鱼藻(Ceratophyllum demersum)为对象, 研究了其在不同碱度(0、7、10、17 mmol/L)和混合盐碱(盐度0.3、0.6、1、2、4 g/L, 相应碱度1.9、3.8、6.3、12.6、25.2 mmol/L)条件下的生理指标变化。结果表明, 盐度在1.5 g/L以下时, 碱度变化没有对金鱼藻造成影响, 在实验设置的碱度梯度范围内, 金鱼藻均能正常生长, 尽管金鱼藻过氧化物酶(POD)、脯氨酸等均显示出梯度变化, 但依旧能够耐受17 mmol/L以下的碱度条件。随着混合盐碱浓度的升高, 金鱼藻长势呈现由盛至衰败的趋势, 在盐度0.6 g/L、碱度3.8 mmol/L的条件下, 金鱼藻长势最好, 表现出低促高抑的效应。随着盐度升高至2 g/L、碱度12.6 mmol/L, 金鱼藻能耐受胁迫并存活一部分, 尽管此时碱度<17 mmol/L, 也有部分金鱼藻死亡, POD含量急剧升高且植株间差异较大; 当盐度升高到4 g/L、碱度达到25.2 mmol/L时, 金鱼藻21天后全部死亡。在对水培液水质的检测中发现, 混合盐碱的浓度越高, 水中氮磷的去除率越低, 两者呈负相关关系。研究结果为盐碱化湖泊的沉水植被恢复提供了一定的参考。  相似文献   

17.
Long-term sampling of intertidal macroalgae along permanently marked transects within San Francisco Bay has shown a marked decline in overall species number along the estuarine gradient from the ocean to the river, presumably as a result of decreasing salinity and a progressive lack of hard substrata in the upstream direction. Green algae penetrated further landward than either brown or red species. Seasonally, macroalgal species diversity is lowest during the winter-spring months when salinity, temperature, and irradiance are at yearly minima. Macroalgal abundance as measured by percent cover was maximum during the late spring near the mouth of the estuary and during late summer towards the head. The seasonal increase in algal abundance is related to increasing salinity, temperature, and light availability to the bottom. The summer increase in irradiance is due to the longer photoperiod, increased frequency of day-time low tides, and reduced levels of suspended sediments. The aperiodic occurrence of algal blooms in San Pablo Bay may be caused by a combination of physical factors which are ultimately associated with the river inflow. A hypothesis based on interannual differences in river inflow and the contribution of phytoplankton to nutrient cycles in the benthos is presented to explain the occurrence of nuisance algal blooms.  相似文献   

18.
Araruama Lagoon is a large, continuously hypersaline coastal lagoon (mean salinity 52 g l-1). However, during certain years the evaporation-precipitation balance is modified and results in lower salinity conditions, e.g. 1989–1990 when the mean salinity measured 41 g l-1. These atypical conditions are responsible for a different behavior of the system, normally characterized by the presence of extensive microbial algal mats, low pelagic primary production compared to benthic primary production, and low turbidity. However, during this study (1989–1990), the presence of microbial algal mats was restricted to the shallow eastern embayment of the lagoon representing c.a. 8% of the total area, the mean concentration of suspended matter was relatively high (21.2 mg l-1) when compared with a typical year, and primary production measured was 447 mg C m-2 d-1, higher than benthic primary production during hypersaline years. These conditions therefore influence the trophic state of the system, during low salinity conditions, the lagoon was meso-eutrophic.  相似文献   

19.
The study presented is an attempt to explain variance in charophyte presence for the territory of Serbia by using several environmental parameters and to find a connection between certain species of charophytes and aquatic macrophytes found growing with them. Environmental parameters used were habitat type, water depth, altitude and four bioclimatic parameters extracted from the WorldClim set of global climate layers. The data used are an outcome of gathering all available literature and herbarium data on charophytes in Serbia ending with the first decade of twenty-first century, and were not systematically collected for the purpose of this study. Of 22 analyzed charophytes, 8 of them are in endangered and 4 in vulnerable IUCN threat categories for the Balkan region. The analyses performed were indicator species analysis (ISA), canonical correspondence analysis (CCA) and partial canonical correspondence analysis (pCCA). ISA distinguished four species of Charophyta as indicators of specific habitat types. Percentages of variance explained were 18.98% and 19.91% for CCA and pCCA, respectively. Depth and altitude were shown to be the most significant environmental factors explaining charophyte occurrence.  相似文献   

20.
Salinity is an important factor influencing growth and survival of aquatic organisms such as Artemia, a valuable aquaculture species. This study evaluated the effects of salinity on A. franciscana populations from different water bodies in Mexico's Pacific Coast. With this purpose, five autochthonous bisexual Artemia populations were tested to assess their survival and growth values against salinities of 40, 60, 80, 100 and 120 g/l, under laboratory conditions (25 +/- 2 degrees C; pH 8-10; constant light and aeration). The organisms were fed with 100 mL of rice bran and 2L of Tetraselmis suecica (500 000 cel/ml). The culture experiments were made in 200L plastic tanks, and survival and growth final values were obtained after 21 culture days. Survival and growth curves were determined by a regression analysis (R2). The significant differences between salinities were determined by ANOVA test (p < 0.05). The best survival and growth rates were found at salinities of 100-120 g/l. When the Mexican Artemia populations were cultivated at 40 g/l of salinity, 100% mortality was observed in the juvenile stage. This study determined that survival and growth values of A. franciscana populations increased with salinity. The five A. franciscana populations presented significant differences in their survival rate under various salinity regimes. The studied populations experienced high mortality at salinities under 60 g/l and over 200 g/l, and especially during the metanauplius stage. The present study confirms that growth rates in Mexican A. franciscana populations from Pacific Coast habitats are not inversely proportional to salinity. These A. franciscana populations should be cultured at 100-120 g/l of salinity to obtain better survival and growth rates. This data is useful to improve culture systems in aquaculture biomass production systems.  相似文献   

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