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青岛地区大气沉降物中碳水化合物初步研究   总被引:1,自引:0,他引:1  
青岛地区大气沉降物中溶解态碳水化合物平均浓度为3.3mg/L,明显高于河水与海水。1991年6-12月DCHO通过大气向海洋输送的通量为840.9mg/m^2,DCHO浓度与降雨量呈岁相关,且DCHO浓度及沉降量的季节变化明显。酸雨使得DCHO浓度升高,改变了碳水化合物在液固相间的分配。  相似文献   
2.
于1989年1月—1989年8月,用连续培养和半连续培养方法进行了伪矮海链藻碳水化合物、蛋白质和生化组成比率的日变化同光强、营养盐关系的研究。结果表明,碳水化合物、碳水化合物同叶绿素a和蛋白质的比值均呈现光照期升高而黑暗期降低的昼夜节律;蛋白质在光照期和黑暗期均有合成,但是,光照期的增长速率大于黑暗期的;蛋白质同叶绿素a的比值无明显的日变化。各指标的日变化幅度均随光强的增强和营养盐供应速率的增加而升高,因此,光和营养盐是影响各指标日变化的重要因素。  相似文献   
3.
Sedimentation and density are important factors influencing the growth of wetland plants. The aim of this study was to elucidate the role of plant density in acclimation to burial stress by investigating the growth, biomass allocation, and carbohydrate contents of Polygonum hydropiper L. var. flaccidum, one of the dominant species in the Dongting Lake wetland, China. Experimental treatments, conducted in a greenhouse, combined three plant densities (16, 144, and 400 plants m−2) with two burial depths (0 and 15 cm) in a factorial design. Greater burial depth and higher plant density had negative effects on biomass accumulation and plant height with some exceptions. Plant growth, although lower at higher densities in general, was unaffected by burial depth at medium and high densities, indicating that the negative effect of burial stress was ameliorated by increased plant density. Deeper burial led to higher stem mass fraction only in the low-density treatment. Belowground mass fraction increased significantly with increasing density in both burial treatments. Moreover, higher density and deeper burial led to higher soluble sugar content but lower starch content. These data indicate that higher density facilitates acclimation of P. hydropiper to burial stress through increased soluble sugar content.  相似文献   
4.
Suspended particulate organic matter (SPOM) both from the oligotrophic Mediterranean and from the more productive Black Sea has been analysed by pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) and by such conventional techniques as elemental analysis and fluorometry. The data achieved by the two approaches generally confirmed and complemented each other. The relative concentrations of pyrolysis products (termed markers) characteristic of chlorophyll (CHL), lipid, carbohydrate (CBH), and protein (PROT) components of SPOM have been determined. The vertical distribution of lipid markers was more uniform in the Mediterranean surface waters. Their relative abundance increased rapidly in the oxycline of the Black Sea, reaching their highest levels in the suboxic zone, where the protein composition of the SPOM changed significantly. In both seas, the relative concentrations of CHL markers increased consistently within the CHL maximum zone where the CBH markers were less abundant. No lignin markers from terrestrial vegetation were detected at significant levels in the pyrograms.  相似文献   
5.
1995年5月-1996年3月,通过一次(分批)培养实验研究了中肋骨条藻和新月菱形藻部分生化组成和性质随培养介质中硝酸盐和磷酸盐水平的变化。结果表明,在氮限制条件下,藻体叶绿素α含量和碱性磷酸酶活力较低,与生长速率呈正相关;碳水化合物含量先随硝酸盐浓度增加而升高,当叶绿素α含量较低时降低。在磷限制条件下,藻体叶绿素α、碳水化合物含量和碱性磷酸酶活力均升高。碳水化合物的积累较氮限制时显著。各生化指标  相似文献   
6.
不同氮磷比对中肋骨条藻生长特性的影响   总被引:29,自引:0,他引:29  
本文对在不同氮磷比(1:1,4:1,16:1,80:1,160:1)的培养条件下,中肋骨条藻的生长和营养生理特征进行了研究。结果表明:中肋骨条藻生长和生理状态受氮磷化的影响比较明显。在N/P=16:1的状态下,其生长速度最快,细胞数量最高;在氮磷比大于16状态下的生长速度要优于氮磷比小于16的营养状态,说明其生长主要受到氮的限制。叶绿素a浓度受氮磷比的影响与细胞的生长基本相一致。相反,藻细胞内碳水化合物和蛋白质的合成和积累量在氮磷比≤16的状态下高于氮磷比大于16的状态。  相似文献   
7.
采用"金字塔"法对瓦氏黄颡鱼幼鱼日粮中主要营养素的需要量进行了研究.试验共持续了60天.实验日粮中蛋白质、脂肪、碳水化合物设定的范围分别为30%-48%、3%-18%和26%-35%.结果表明,当日粮碳水化合物在26%-32%,脂肪6%-12%,蛋白质39%-48%,能量在15.63-16.95MJ/kg和能量蛋白比为364-435J/mg时,瓦氏黄颡鱼幼鱼均获得较好的生长率;日粮脂肪水平为12%以上时肝组织有不同程度的脂肪变性和坏死;肌肉蛋白质、脂肪和碳水化合物的沉积受日粮中的蛋白质、脂肪和碳水化合物的影响,存在显著性差异(P<0.05);肝体指数和肠脂比随日粮中脂肪含量升高而增大,肝脏中的糖原含量受到日粮中添加碳水化合物水平的影响,且有显著差异(P<0.05);日粮中可消化能显著影响肌肉中脂肪的沉积,肠脂比、肝体指数和内脏比都随日粮中可消化能水平提高而呈上升趋势.本实验结果表明,瓦氏黄颡鱼幼鱼日粮中主要营养素的适宜需要量为蛋白质39%-42%、脂肪6%-9%、碳水化合物26%-29%、能量15.63-16.95MJ/kg、能量蛋白比364-435J/mg.  相似文献   
8.
在实验室条件下,研究了氮磷比、温度、光照强度等环境因子对中肋骨条藻细胞碳水化合物,氨基酸、蛋白质含量的影响。结果表明:当介质N/P为10:1时生化组成含量比30:1高;在28℃时,其生化含量高;高光照强度下藻生化组成含量比低光照大。  相似文献   
9.
Suspended particulate matter (SPM) samples were collected from the surface seawaters at 31 stations, and from various depths (2 to 1000 m) at 9 locations in the northern Indian Ocean during various seasons. SPM samples were analyzed for total particulate carbohydrate (TPCHO), total particulate uronic acid (TPURA) and total particulate neutral carbohydrate (TPNCHO) concentrations and composition. Strong spatial, temporal and depth related variations were evident in the distribution of these compounds. In surface waters, concentrations of TPCHO, TPNCHO, and TPURA varied from 0.57 to 3.58 μM C, 0.11 to 2.34 μM C, and from 0.01 to 0.31 μM C, respectively, and accounted for 2.6 to 34.6%, 2 to 24.5%, and 0.2 to 6.3% of POC, respectively, whereas the TPURA accounted for 4.7 to 22.7% of TPCHO. Concentrations and yields of both TPNCHO and TPURA decreased rapidly in the upper 100 m of the water column suggesting their utilization by heterotrophic organisms. Glucose was the most abundant constituent of the TPNCHO. Glucose mole fraction decreased while that of other monosaccharides, especially galactose, arabinose, mannose, rhamnose and fucose increased in the upper 100 m water. Below this depth, mole fraction of glucose increased while that of other sugars decreased with the increasing water depth. Generally, high C:N ratios were associated with low yields of carbohydrates and uronic acids. Inverse correlation between the mole fractions of arabinose plus xylose and rhamnose plus fucose indicates the importance of biogenic and terrestrial organic matter input to the Bay of Bengal. TPURA are surface-active in nature and thus may play an important role in coagulation of particles and macromolecules. The observed spatial and seasonal variations of these compounds may be due to differences in phytoplankton biomass, nutrient status, and the influence of terrestrial material.  相似文献   
10.
于1989年1月—1989年8月,用连续培养和半连续培养方法进行了伪矮海链藻碳水化合物、蛋白质和生化组成比率的日变化同光强、营养盐关系的研究。结果表明,碳水化合物、碳水化合物同叶绿素α和蛋白质的比值均呈现光照期升高而黑暗期降低的昼夜节律;蛋白质在光照期和黑暗期均有合成,但是,光照期的增长速率大于黑暗期的;蛋白质同叶绿素α的比值无明显的日变化。各指标的日变化幅度均随光强的增强和营养盐供应速率的增加而升高,因此,光和营养盐是影响各指标日变化的重要因素。  相似文献   
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