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1.
目的:通过测定刺参养殖池表层沉积物的理化、生物指标含量,分析它们之间的相关性及对刺参生长的影响。方法:采用标准养殖环境沉积物检测规范。结果:沉积物中总氮含量范围291~360μg·g^-1,平均含量为300μg·g^-1,均未超过生态毒性值(550μg·g^-1);总磷含量较高,达到408~631μg·g^-1,平均含量为543μg·g^-1,有3个养殖池总磷含量超标;硫化物含量范围174~456μg·g^-1,平均含量298μg·g^-1;有机质含量达到2.10%~4.60%;底栖硅藻含量为5.50~44.5×10^6cells·m^-2,平均含量18.6×10^6cells·m^-2;总异养菌含量平均范围在1.33×10^6~100×10^6cfu·g^-1;其中总氮含量与含水率、有机质的相关性达到0.946、0.956,硫化物含量与底栖硅藻相关性为0.827,总磷含量与其它物质含量无明显相关性。结论:总氮含量与含水率、有机质含量呈极显著正相关;硫化物含量分别与底气硅藻含量和总异养菌含量呈显著正相关;其他本底值之间相关性不显著。刺参生长受环境影响明显,如果底栖硅藻含量丰富,其他营养盐含量较低,则刺参生长良好。  相似文献   

2.
寡盐水鱼池藻菌土腥异味化合物研究   总被引:1,自引:0,他引:1  
徐立蒲  潘勇  曹欢  殷守仁  熊邦喜 《生态学报》2008,28(10):5173-5178
通过利用固相微萃取-气质联用色谱测定天津市寡盐水养鱼池中浮游藻类和放线菌的次生代谢产物——土腥异味化合物(土臭味素和二甲基异莰醇)浓度,感官评价养殖鱼土腥异味程度,同时测定浮游藻类和放线菌生物量,探讨鱼池中土臭味素和二甲基异莰醇浓度、浮游藻类和放线菌生物量以及养殖鱼异味之间的相互关系。结果表明,寡盐水养鱼池水体中普遍存在土臭味素和二甲基异莰醇,其中二甲基异莰醇是鱼池中的主要异味物质,浓度0.33—5302.70ng·L^-1,土臭味素浓度相对较低,0.29~12.10ng·L^-1。养鱼池中共测到6门94属的浮游藻类,生物量0.07~186.48mg·L^-1,以蓝藻Cyanophyta、裸藻Euglenophyta等种类为主。放线菌共测到3个属,总生物量0.01×10^4-1.50×10^4个·L^-1,以链霉菌属Streptomyces为主。巨颤藻Oscillatoria princeps和放线菌是天津地区寡盐水养鱼池中能够产生二甲基异莰的主要产源。水体异味和鱼肉发生异味不同步。  相似文献   

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三种重金属在克氏原螯虾体内的富集特征   总被引:4,自引:0,他引:4  
2005年5月在合肥市、肥东县、肥西县的池塘河沟采集雌雄组克氏原螯虾共30只,分离出几丁质外骨骼、肝脏和腹部肌肉组织样品84份,用原子吸收法测定其中Cd、Pb、Cr的残留量。结果表明:克氏原螯虾体内Cr、Cd和Pb的平均检出率分别为100%,91.7%和94.1%;平均含量分别为4.03、0.38和7.14μg·g^-1。Cr的富集量在3种组织之间的差异不显著,cd和Pb在3种组织中差异极其显著。外骨骼中Cr、Cd、Pb的平均含量分别为4.03、0.12和12.31μg·g^-1,合肥市、肥西、肥东三地之间除Cr的富集量差异极显著外,其他2种重金属的富集量差异都不显著;肝脏中Cr、Cd、Pb的平均含量分别为3.88、1.04和9.12μg·g^-1,3个地区重金属的富集量的差异都极其显著;肌肉中Cr、Cd、Pb的平均含量分别为4.16、0.09和0.72μg·g^-1,3个地区除重金属Cr的富集量差异极显著外,Cd和Pb的差异都不显著。3种重金属污染物的富集量与体质量没有明显的相关性。3种重金属在雌雄个体之间的富集差异不显著。  相似文献   

4.
杨松  王志香  周光益 《生态科学》2009,28(4):305-310
选择三种乡土树种樟树、大头茶和红鳞蒲桃,喷洒含有不同浓度的Cu和Pb溶液,同时设置一个没有喷洒重金属的空白实验。设置的浓度梯度Cu为0mg·L^-1、50mg·L^-1、150mg·L^-1、250mg·L^-1;Pb为0mg·L^-1、10mg·L^-1、20mg·L^-1、30mg·L^-1。培育期结束后测量三个树种的树高;根、茎、叶的生物量和总生物量;以及叶片生物膜的透性和SOD的活性。结果表明(1)随着重金属浓度的增加,三种乡土树种的高生长和生物量的增加都受到了显著的抑制,浓度越高抑制越明显。相较而言红鳞蒲桃长势较好。(2)随着Cu、Pb浓度的升高,植物叶片的质膜透性变强,受到的伤害增大。Cu250mg·L^-1下樟树叶片生物膜受到伤害最大,而在Pb30mg·L^-1下大头茶叶片质膜受到伤害最大。(3)SOD活性在Cu的胁迫下呈现随着浓度的增加,先升高后下降的规律,但大头茶的SOD活性在一直增加。(4)在Pb的胁迫下,SOD的活性随胁迫的浓度的升高一直下降,只有红鳞蒲桃在后期表现出了增长的趋势。  相似文献   

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选取三江平原典型沼泽湿地植物小叶章为对象,通过野外控制试验(2004-2007年),研究了4个不同氮素输入水平[0(对照,CK)、6(N6)、12(N12)和24(N24)g·m^-2·a^-1]对小叶章叶片形态、叶绿素和生物量累积等的影响.结果表明:不同氮处理间小叶章叶长和叶宽未出现显著差异,比叶面积在N。:处理时最小[(149.54±18.27)cm^2·g^-1],即此氮处理水平下叶片的厚度最大.叶片的叶绿素含量均呈单峰型变化,峰前,随着氮输入量的增大而增大,且N12和N24处理下峰值出现的时间早于N6和CK处理;峰后,N24处理下叶绿素含量迅速降低,N6处理则降低缓慢,说明适量的氮输入延缓了叶片衰老.连续的高氮(N24)输入使小叶章的生长发育有所提前,在成熟后叶片出现早衰现象.2005和2007年生长季末,小叶章地上部分生物量均随着外源氮输入量的增加而增大,但是经过4年(2007年)连续高氮(N24)处理的小叶章地上部分生物量较输入2年(2005年)时降低了53.72%.  相似文献   

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马蹄金叶片中铜、铅含量及其对生理指标的影响   总被引:15,自引:0,他引:15  
研究了草坪草马蹄金对不同污染土壤的Cu、Pb含量.结果表明,马蹄金体内Cu含量(44.8mg.kg^-1)高于Pb含量(25.59mg·kg^-1).两种元素在体内的分布特征是根、茎>叶(P<0.05),并随着土壤内重金属含量增加而增加,但富集系数呈下降趋势;马蹄金对Cu的富集系数(0.784)高于Pb的富集系数(0.465).自然状态下不同程度Cu、Pb复合污染对马蹄金叶片细胞膜及细胞保护系统的影响结果表明,随着Cu、Pb浓度增加,叶片内叶绿素a、叶绿素a/b分别由1.610mg·g^-1 FW和4.100.下降到1.017mg·g^-1 FW和2.299;SOD活性先升高至106.494U·g^-1 FW,随后下降至86.258U·g^-1 FW;POD活性则逐渐增加;而细胞膜透性变化不明显。  相似文献   

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利用正交试验L16(4^5)对影响獐(Hydropotes inermis)ISSR-PCR反应的TaqDNA聚合酶浓度、dNTP浓度、引物浓度、Mg^2+浓度及模板DNA浓度5个因素在4个水平上进行优化,同时对退火温度进行梯度PCR反应,以建立适合于獐ISSR-PCR反应的最佳体系。最终确定獐25gLISSR-PCR反应体系为:Taq酶1.25U&#183;25μL^-1、Mg^2+浓度2.5mmol&#183;L^-1、引物浓度0.3μmol&#183;L^-1、DNA模板量350ng&#183;25μL^-1、dNTP浓度0.15mmol&#183;L^-1。在此基础上,利用优化的反应体系成功筛选出10条用于獐相关研究的ISSR引物并确定了各自的最佳退火温度,为今后利用ISSR技术进行獐的物种鉴定与分类、亲缘关系、系统发育和生理病理学研究奠定了技术基础,也为开展其它大型资源动物如黑麂的保护遗传学研究提供理论基础。  相似文献   

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喀斯特石漠化地区土壤温室气体的地气交换特征   总被引:2,自引:0,他引:2  
利用密闭箱一气相色谱法于2006-2007年对黔中喀斯特地区土壤二氧化碳、氧化亚氮和甲烷的释放通量进行原位观测,研究我国南方喀斯特石漠化地区土壤温室气体地气交换特征。结果表明:喀斯特石漠化地区土壤是大气C02、N20的释放源,CH4的吸收汇。土壤CO2的释放通量介于450.8&#177;50.8—1281.3&#177;214.7mg&#183;m^2&#183;h^-1在之间,夏秋季节高于冬春季节;N2O的释放通量介于.25.4&#177;4.1~105.8&#177;31.2μg&#183;m^-2&#183;h^-1之间,在夏季最高,在9月、11月和12月出现土壤对大气N2O的吸收;全年CH4交换通量介于.0.27&#177;0.18-0.81&#177;0.26mg&#183;m^-2&#183;h^-1之间,随季节的变化不明显。气候条件对土壤CO2和CH4交换通量的影响较小,土壤水分对N2O释放通量的影响效应在不同的季节不同。相关分析结果显示,土壤N2O和CH4地气交换通量受到土壤硝态氮含量的调控。  相似文献   

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精胺对荇菜抗氧化酶系汞毒害的缓解作用   总被引:1,自引:0,他引:1  
研究了外施不同浓度的精胺(Spm)对15μmol&#183;L^-1汞胁迫下,荇菜(Nymphoides pehatum)叶中SOD、CAT、APX、POD保护酶的活性、O2^-产生速率、MDA、叶绿素、可溶性蛋白、游离态多胺含量的影响。结果表明:外施0.05~0.5mmol&#183;L^-1的Spn,显著提高了汞胁迫下荇菜叶内的亚精胺、精胺水平以及叶绿素和可溶性蛋白的含量;并能提高SOD、CAT和APX的活性,降低O2^-的产生速率,减缓MDA的积累;0.05~0.5mmol&#183;L^-1的外源Spm可增强植物抗氧化胁迫的能力,缓解汞对荇菜的毒害作用,其中0.05~0.1mmol&#183;L^-1的外源Spm效果最佳,但当Spm浓度达到5mmol&#183;L^-1时,却加剧了汞的毒害作用。  相似文献   

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珠江口横琴岛海域春季海洋浮游生物的初步研究   总被引:1,自引:0,他引:1  
根据2008年5月在珠江口横琴岛海域的调查采样,本文对该海域的叶绿素a、初级生产力(C)、浮游动、植物进行了初步的研究,分析了浮游动、植物的种类组成、群落结构、数量和生物量等。结果表明,叶绿素a浓度和初级生产力(C)均值分别为5.27mg&#183;m^-3和123.56mg&#183;m^-2&#183;d^-1。浮游植物共有111种,以硅藻为主,绝对优势种为中肋骨条藻Skeletonema costamm,调查海域浮游植物平均细胞丰度为6832.75&#215;10^4cell&#183;m^-3,以近海广布种为主要类群,多样性指数和均匀度均值分别为2.29和0.45。浮游动物共有41种,暖水种沿岸类群种类占大多数,以中华异水蚤Acartiella smensis为绝对优势种,平均丰度和生物量分别742.25ind&#183;m^-3和131.12mg&#183;m^-3,多样性指数和均匀度均值分别为2.54和0.67。  相似文献   

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Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.  相似文献   

12.
The lactate dehydrogenase activity in reactions of lactate oxidation and synthesis was studied in subfractions of the chicken brain, heart and liver at the embryonal, early postembryonal and adult stages of development after thyroxine administration. It has been shown that during embryogenesis thyroxine predominantly enhanced the rate of lactate oxidation in the mitochondrial tissues. A marked increase in the lactate synthesis was found in cytoplasm of the adult chicken tissues. Specificity of enzyme activity alterations was detected in the chicken brain during ontogenesis after thyroxine administration.  相似文献   

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In order to determine if the absence of vitamin C in the diet of capybaras (Hydrochoerus hydrochaeris) causes scurvy, a group of seven young individuals were fed food pellets without ascorbic acid, while another group of eight individuals received the same food with 1 g of ascorbic acid per animal per day. Animals in the first group developed signs of scurvy-like gingivitis, breaking of the incisors and death of one animal. Clinical signs appeared between 25 and 104 days from the beginning of the trial in all individuals. Growth rates of individuals deprived of vitamin C was considerably less than those observed in the control group. Deficiency of ascorbic acid had a severe effect on reproduction of another population of captive capybaras. We found that the decrease in ascorbic acid content in the diet affected pregnancy, especially during the first stages. The results obtained suggest that it is necessary to supply a suitable quantity of vitamin C in the diet of this species in captivity.  相似文献   

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Somatostatin (SST) peptide is a potent inhibitor of insulin secretion and its effect is mediated via somatostatin receptor 5 (SSTR5) in the endocrine pancreas. To investigate the consequences of gene ablation of SSTR5 in the mouse pancreas, we have generated a mouse model in which the SSTR5 gene was specifically knocked down in the pancreatic beta cells (betaSSTR5Kd) using the Cre-lox system. Immunohistochemistry analysis showed that SSTR5 gene expression was absent in beta cells at three months of age. At the time of gene ablation, betaSSTR5Kd mice demonstrated glucose intolerance with lack of insulin response and significantly reduced serum insulin levels. Insulin tolerance test demonstrated a significant increase of insulin clearance in vivo at the same age. In vitro studies demonstrated an absence of response to SST-28 stimulation in the betaSSTR5Kd mouse islet, which was associated with a significantly reduced SST expression level in betaSSTR5Kd mice pancreata. In addition, betaSSTR5Kd mice had significantly reduced serum glucose levels and increased serum insulin levels at 12 months of age. Glucose tolerance test at an older age also indicated a persistently higher insulin level in betaSSTR5Kd mice. Further studies of betaSSTR5Kd mice had revealed elevated serum C-peptide levels at both 3 and 12 months of age, suggesting that these mice are capable of producing and releasing insulin to the periphery. These results support the hypothesis that SSTR5 plays a pivotal role in the regulation of insulin secretion in the mouse pancreas.  相似文献   

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