衣藻对Cu2+生物积累过程及其效应的研究

以莱茵衣藻为材料，研究了Cu^2 的生物积累／吸附过程以及Cu^2 对衣藻光合作用的影响，并对两的关系进行了初步讨论。结果表明，衣藻对Cu^2 的生物吸收／吸附速率在10分钟内达平衡；1．0mg/L的Cu^2 对衣藻光合作用的影响较小，5．0、10．0、20．0mg/L的Cu^2 对衣藻光合作用的影响较大，40．0mg/L的Cu^2 可完全抑制衣藻的光合作用。Cu^2 在衣藻细胞内的生物积累和由此引起的生理功能的变化是同步进行的。     

三峡水库香溪河库湾拟多甲藻(Peridiniopsis)水华对环境中磷的响应机制

于2015年春季拟多甲藻水华暴发期在香溪河支流高岚河、南阳河与干流设置9个采样点,探讨浮游植物种群与水体总磷浓度等环境因子的相关性;同时,分离纯化拟多甲藻后,设置5个不同磷浓度(0、0.005、0.020、0.100、0.600 mg/L)对其进行实验室培养,分别测定其比生长速率;在对数生长期,检测不同磷浓度培养下的藻细胞的快速光曲线及其参数;检测不同磷浓度培养下的藻细胞对外源无机碳的吸收效率及其参数.结果表明,水体中总磷浓度越高的河段,拟多甲藻细胞密度越高;培养基中磷浓度越高,拟多甲藻的比生长速率越大,光合效率越高,其对外源无机碳的吸收能力越强.这些结果表明高磷的水环境可能是促使拟多甲藻形成水华的关键因素之一.     

不同温度培养下莕菜(Nymphoides peltata)生长与光合作用特征

以太湖东山与西山之间水域的莕菜根茎为实验材料,在室内分别进行3种温度(28、30、32℃)处理,利用Li-6400便携式光合作用测量系统,分别测定3种温度处理下莕菜的光响应曲线和CO2响应曲线,并且利用非直角双曲线法进行拟合,得到相关参数.结果表明,3种温度下,莕菜的光合能力大小顺序表现为30℃>32℃>28℃,羧化效率为32℃>30℃>28℃,蒸腾速率、气孔导度均为30℃>28℃>32℃;28、30和32℃下的单位叶片生物量分别为0.0019±0.0002、0.0021±0.0003、0.0020±0.0003 g(DW)/cm2,叶片及其单位面积生物量为30℃>28℃>32℃,但差异不显著;30℃下的根、茎干重显著高于另外2个温度下的.在低于30℃的温度条件下,随着温度的升高,莕菜的光合能力均明显升高,促进了植物的生长;而当温度超过30℃后,光合作用效率降低,植物的生长则受到抑制.在适宜温度范围内(<30℃),小幅度的升温(2℃)产生了显著的积温效应(200℃.d),促进了莕菜的生长.因此推断,1998 2006年太湖地区平均气温升高约1.0℃的现象对近年来太湖莕菜的大面积扩张可能具有促进作用.     

经济海藻羊栖菜（Sargassum fusiforme）幼体对镉胁迫的响应特性

镉(Cd)是水生生态环境中常见的重金属污染物,通常会抑制植物的生长,减少生物量,对植物产生毒害作用。为了研究羊栖菜幼苗对海水中Cd胁迫的抗氧化响应特性,我们在天然海水和Cd加富(100 μmol·L^-1)海水两种不同的Cd浓度下培养羊栖菜幼体。实验结果表明:Cd加富胁迫显著抑制了羊栖菜幼苗生长,使藻体颜色变暗。此外,高Cd处理显著降低了羊栖菜中的色素含量,生长速率,过氧化物酶(POD)活性,脱氢抗坏血酸(DHA)含量和谷胱甘肽还原酶(GR)活性。相反,高Cd处理显著促进了藻体内的Cd元素积累、对Cd₂⁺吸收速率,并增加了其暗呼吸/净光合速率比值(R_d/P_n),抗坏血酸(Vc)含量,可溶性蛋白质(SP)含量,且还原型谷胱甘肽(GSH)以及羊栖菜的超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性均显著增加,但对丙二醛(MDA)的影响不显著。虽然羊栖菜幼苗增加了其抗氧化活性并促进AsA-GSH循环,以产生H₂O₂并维持健康的新陈代谢,但高Cd胁迫显著限制了幼苗的光合作用,降低了其光合色素,抑制了其生长,并使其藻体颜色发生变化。海水中高浓度的Cd对羊栖菜幼苗具有毒性作用,并且极大地增加了这种海藻的食用风险。     

三种大型钙化绿藻仙掌藻对海水变化的生理响应

The effects of seawater temperature on the physiological performance of three Halimeda species were studied for a period of 28 d. Five treatments were established for Halimeda cylindracea, Halimeda opuntia and Halimeda lacunalis, in triplicate aquaria representing a factorial temperature with 24°C, 28°C, 32°C, 34°C and 36°C,respectively. The average F_v/F_m of these species ranged from 0.732 to 0.756 between 24°C and 32°C but declined sharply between 34°C(0.457±0.035) and 36°C(0.122±0.014). Calcification was highest at 28°C, with net calcification rates(Gnet) of(20.082±2.482) mg/(g·d),(12.825±1.623) mg/(g·d) and(6.411±1.029) mg/(g·d) for H.cylindracea, H. opuntia and H. lacunalis, respectively. Between 24°C and 32°C, the specific growth rate(SGR) of H.lacunalis(0.079%–0.110% d~(–1)) was lower than that of H. cylindracea(0.652%–1.644% d~(–1)) and H. opuntia(0.360%–1.527% d~(–1)). Three Halimeda species gradually bleached at 36°C during the study period.Malondialdehyde(MDA) and proline levels in tissues of the three Halimeda were higher in 34–36°C than those in24–32°C. The results indicate that seawater temperature with range of 24–32°C could benefit the growth and calcification of these Halimeda species, however, extreme temperatures above 34°C have negative impacts. The measured physiological parameters also revealed that H. cylindracea and H. opuntia displayed broader temperature tolerance than H. lacunalis.     

Influence of non-photosynthetic pigments on light absorption and quantum yield of photosynthesis in the western equatorial Pacific and the Subarctic North Pacific

Regional variations in the contribution of non-photosynthetic pigments (ā _np^*) to the total light absorption of phytoplankton (ā _ph^*) and its influence on the maximum quantum yield of photosynthesis (φ _m) were investigated. In the western equatorial Pacific, the surface ā _np^* : ā _ph^* ratio was higher in the western warm pool than that in the upwelling region. This difference appears to be attributable to severe nitrate depletion and higher percentage of prokaryotes, which can accumulate very high concentrations of zeaxanthin in the western warm pool. In the subarctic North Pacific, the ā _np^* : ā _ph^* ratio was expected to be higher in the Alaskan Gyre where the thermocline is sharper and iron limitation may possibly be more severe than in the Western Subarctic Gyre. However, the ratio was actually higher in the Western Subarctic Gyre, contradictory to our expectations. This east-west variation appears to be attributable to changes in the taxonomic composition; cyanobacteria were more abundant in the Western Subarctic Gyre. The values of ā _np^* : ā _ph^* and its vertical variations were relatively small in the subarctic North Pacific compared to those in the western equatorial Pacific. These inter-regional variations appear to be attributable to the lower solar radiation intensity, smaller percentage of cyanobacteria, and relatively strong vertical mixing in the subarctic North Pacific. The spatial variations in ā _np^* : ā _ph^* significantly influence φ _m. In comparison with φ _m based on the total light absorption (φ _{m ph}), the values corrected for the contribution of non-photosynthetic pigments (φ _{m ps}) showed an increase in both the western equatorial Pacific and the subarctic North Pacific.     

阳光紫外辐射对羊栖菜人工幼苗生长和光合电子传递速率的影响

为探讨经济褐藻羊栖菜人工幼苗对阳光紫外辐射变化的响应,在全波段阳光辐射省(PAB,280～700nm)、去除UV-B辐射(PA,320～700nm)和光合有效辐射PAR(P,400～700nm)三种辐射处理及不同辐射水平下培养羊栖菜幼苗,并测定了其生长与光合作用的变化。结果表明,无论在紫外辐射(UVR)存在情况下(PA,PAB)还是滤除UVR(PAR)时,高辐射水平条件下(55%),羊栖菜幼苗都具有较高的生长速率,而低辐射水平下羊栖菜的生长速率较低。在不同辐射处理之间,随着辐射水平的增高,UVR的抑制效应逐渐突显。UVR降低羊栖菜幼苗的光合电子传递速率。     

台湾海峡西部海域水体中的二氧化碳体系

据１９８４年５月至１９８５年２月的调查资料，计算了该水体中二氧化碳体系各要素的统计值，着重研究了它们的季节变化及其与水文，化学和生物因子的关系。结果表明该水体中ＰＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，ＨＣＯ３，∑ＣＯ２，ＣＯ＾２＾－３／∑ＣＯ２，ＨＣＯ３／∑ＣＯ２，ＨＣＯ２，ＣＯ２（Ｔ），ＣＯ＾２＾－３，∑ＣＯ２／Ｃｌ，Ωｃ，Ωａ和Ｃ：Ｎ：Ｐ平均值依次分别为２５１ｄＰａ，８．４３μｍｏｌ／ｄｍ×３     

不同地下水埋深下骆驼刺幼苗叶片生理参数光响应特性

为探讨地下水位变化对骆驼刺(Alhagi sparsifolia Shap.)幼苗生长发育的影响,2008年9月在塔克拉玛干沙漠南缘绿洲外围,利用Li-6400光合作用仪测定了人工控制1,1.5,2.0,2.5 m地下水埋深下骆驼刺幼苗叶片净光合速率(Pn),蒸腾速率(Tr),水分利用效率(WUE)等生理参数对有效光辐...