首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
大型海藻类光合无机碳利用研究进展   总被引:14,自引:1,他引:14  
概述了大型海藻类光合作用无机碳利用近年来的研究进展。大型海藻类除能利用CO2作为光合作用外在无机碳源外,许多大型海藻还能利用HCO^3作为光合作用外在碳源。HCO^3的利用主要为胞外CA催化的HCO^3与CO^2的相互转化及HCO^3的直接吸收两种方式。在三类大型海藻中,地机碳利用各有其独特性。无机碳浓度增高对大型海藻光合无机碳利和产生很大影响。  相似文献   

2.
定量研究黄渤海近海大型经济海藻的面积、产量及其固碳能力和空间分布,对海洋牧场建设和海藻固碳强度研究具有重要意义。基于2001—2016年《中国渔业统计年鉴》和2016年《山东渔业统计年鉴》数据,对2001—2015年黄渤海近海和全国近海养殖大型经济海藻的产量、面积及结构进行了对比分析,采用CCI指数计算了黄渤海近海及全国近海大型经济海藻的固碳能力,并分析了2016年山东省养殖海藻的空间分布特征。研究表明:2001—2015年海藻养殖面积、产量整体呈上升趋势,其中全国海藻养殖面积在2005—2007年,产量在2006—2007年出现间断性下降,黄渤海海藻养殖面积在2005—2007年,产量在2001—2003年、2005—2008年出现阶段性下降;黄渤海近海海藻养殖产量占全国近海海藻养殖产量年均约45.53%,固碳总量占全国海藻固碳总量年均约51.75%,其中裙带菜,海带及紫菜为黄渤海海藻养殖的主要经济藻类;以山东省为典型省份的海藻固碳强度在海岸带间表现出明显的空间分布差异,其中威海市荣成区域人工养殖海藻固碳总量最多。  相似文献   

3.
邵魁双  巩宁  王立军  曲翊  杜念东 《海洋学报》2019,41(12):113-120
底栖海藻是海洋生态系统中重要的初级生产力,开展其固碳和储碳机制研究,有利于提高对我国海域海洋固碳和储碳潜力的认识。本文基于海区条件的模拟,开展了大连海域潮间带优势海藻的日固碳量、日呼吸量和日有机碳释放量的测定,结合海区生物量的调查,阐述了3个海藻床潮间带海藻固碳和储碳的季节变化规律。结果显示:在海藻固碳能力方面,绿藻类的固碳能力最强,褐藻类次之,红藻类最低。大连海域潮间带海藻的固碳量、储碳量和有机碳释放量在12月至5月处于较高水平,6月至11月较低,平均每个海藻床潮间带区域年固碳量和年有机碳释放量分别为1.72×105 g/a和2.1×104 g/a。潮间带海藻月固碳量是储碳量的1.7倍。  相似文献   

4.
海洋碳循环是全球碳循环的重要组成部分,是影响全球变化的关键控制环节。海洋是地球最大的碳库,是地球吸纳CO2的重要缓冲器。海水中溶解无机碳是海洋CO2系统的重要参数,利用AS-C3型溶解性无机碳分析仪进行不同盐度海水溶解无机碳的测量,利用t检验法检验使用仪器的测量精度,探寻盐度与海水总溶解无机碳的关系。实验结果表明:AS-C3型溶解性无机碳分析仪的测量精度在±0.3μmol/L左右,测量过程中无系统差异;海水盐度与总溶解无机碳呈正相关关系,即盐度增大,海水总溶解无机碳增加。最后总结了海水总溶解无机碳测量时的影响因素,如N2纯度、气流状况、实验过程中的温度控制等。  相似文献   

5.
丙酮酸羧化酶(pyruvate carboxylase, PYC)在非光合生物中催化丙酮酸羧化生成草酰乙酸(oxaloacetate, OAA), 作为糖异生的第一步, 在动物维持代谢稳态中具有重要作用。研究发现, PYC在光合生物中也发挥重要作用。为了探究PYC在潮间带大型海藻中的作用, 我们从条斑紫菜叶状体中扩增获得PYC基因全长序列(命名为PyPYC), 并分析了其序列特征。通过对系统进化树分析表明PyPYC与来自细菌的PYC具有较近亲缘关系。针对条斑紫菜叶状体生长环境所面临的碳源变化, 设置了不同类型和不同浓度的无机碳培养条件, 采用实时荧光定量(RT-qPCR)检测了该基因对这些无机碳源的响应。结果表明, 高浓度的CO2能显著上调PyPYC基因的表达, 而高浓度的HCO3?对其影响较小。由此, 我们初步认为, 当紫菜叶状体暴露在空气中时, PYC在其无机碳利用中发挥一定作用。  相似文献   

6.
正《南海常见大型海藻图鉴》和《黄、渤海及东海常见大型海藻图鉴》套书日前由海洋出版社出版发行。该套书鉴定我国南海海域大型海藻101种,黄、渤海及东海海域大型海藻118种,首次详细记录我国海域常见大型海藻的外观形态以及组织和细胞结构,是目前该领域少有的、较全面的图鉴。大型海藻是海洋生态系统重要的初级生产力,在光合固碳和生物地球化学循环等方面具有重要的生态  相似文献   

7.
文章介绍了大型海藻作为一种新的生物质能源,生长速度快、繁殖周期短,不与粮争地,对农产品的产量和价格没有影响,所以以大型海藻为主的生物质能成为生物质能研究的新焦点。大型海藻对水环境的适应能力强,对维持海洋生态系统的平衡有很重要的意义。分析和探讨在三沙市海域进行大型海藻养殖,可以充分利用海洋资源,发展新能源。  相似文献   

8.
采用色谱法分析获得了10种常见海藻中的 F–、Cl–、组成特征,并初步探讨了其阴离子组成与海水环境的初步关系.结果表明,主要无机阴离子总含量褐藻高于绿藻和红藻,且存在显著性差异;褐藻和绿藻门的羽藻容易富集碘,是良好的生物碘源.通过多元统计分析显示 Cl–与 I–相关程度最密切(r=0.681),其次是主要是F–、SO ?和缩因子与海水中该元素逗留时间的对数相关统计表明,孔石莼、浒苔和鼠尾藻的相关系数大于0.9,说明某些海藻与海水中的非金属无机元素的分布迁移有密切的联系,研究近岸区域海藻中无机非金属元素的组成可为揭示元素生物地球化学循环提供重要讯息.PO ?与 I–以及34 PO ?与 Cl–;主成分 1 34 24 NO?贡献比较大,主成分2主要是3 PO ?、Cl–及I–贡献比较大.海藻中阴离子的浓34 SO ?、24 PO ?、34 NO?、I–等无机阴离子的3  相似文献   

9.
我国近海藻类养殖的碳汇强度估算   总被引:4,自引:0,他引:4       下载免费PDF全文
从海藻养殖群落的碳汇强度和近岸碳循环过程的角度出发,对当前海藻养殖碳循环的研究现状进行总结陈述,并根据最新公布的FAO数据,在综合考虑藻类产量和进入水体和沉积物中POC和DOC的基础上,对2009年全球和中国主要养殖藻类的固碳能力进行了初步估算.研究结果显示,2009年中国的海水藻类养殖固碳总量为78.38×104 t...  相似文献   

10.
辽东湾柱状沉积物中无机碳的形态   总被引:1,自引:1,他引:0  
根据沉积物中无机碳的结合强度,运用连续浸取的方法将沉积物中的无机碳分成5种不同的形态:NaCl相、氨水相、NaOH相、盐酸羟胺相、HCl相。并以渤海辽东湾柱状沉积物为例,探讨了各形态无机碳的含量特征及其控制因素。研究表明,辽东湾不同层次沉积物中各形态无机碳的含量特征比较明显:氨水相>盐酸羟胺相≈盐酸相>NaOH相>NaCl相。氨水相、盐酸羟胺相和盐酸相无机碳占沉积物中总无机碳的绝大部分,大于80%;NaCl相和NaOH相无机碳只占总无机碳的一小部分。沉积物中各形态无机碳含量的变化受沉积环境如pH、Eh、Es、含水率、Fe3 /Fe2 、有机碳含量等因素的影响。其中NaCl相无机碳受pH、Eh影响较大;氨水相无机碳主要由含水率、Fe3 /Fe2 、pH、Eh控制;NaOH相无机碳主要由含水率、Eh和pH控制;盐酸羟胺相无机碳主要受含水率、Eh、有机碳的影响;HCl相无机碳的控制因素和盐酸羟胺相的相似,但它受pH和Eh的影响更显著。虽然有机碳和各个形态的无机碳都呈负相关关系,但它对每一形态的影响都不相同,其作用受其它环境因素的制约。环境的氧化能力越强,pH值越小,越不利于盐酸羟胺相和盐酸相无机碳的保存,而有利于NaCl相、氨水相和NaOH相无机碳的形成;环境的还原能力越强,pH值越大,越有利于盐酸羟胺相和盐酸相无机碳的保存,而不利于NaCl相、氨水相和NaOH相无机碳的形成。辽东湾沉积物的弱氧化-还原环境有利于盐酸羟胺相和盐酸相无机碳的保存。  相似文献   

11.
Lagoa de Araruama in the state of Rio de Janeiro, Brazil, is a hypersaline lagoon with salinity varying spatially from 45 to 56. We collected water samples during monthly cruises throughout the lagoon, and along the streams feeding the system, from April 1991 to March 1992. Nutrients and other water quality parameters exhibited great spatial and temporal variations. Mass balance calculations indicate large amounts of anthropogenic nutrient inputs. The data indicate that the lagoon currently is oligotrophic but is in a state of transition to become a mesotrophic system. Molar dissolved inorganic nitrogen:dissolved inorganic phosphorus (DIN/DIP) varied between 2.2:1 and 659:1 with a volume-weighted average of 22:1. The high DIN/DIP ratio contrasts with that found in nearby lagoons, suggesting that phytoplankton primary production is limited by phosphorus in Lagoa de Araruama. The major loss of DIP is apparently driven by biological assimilation and diagenic reactions in the sediments. Calculations indicate that the lagoon is slightly net autotrophic at +0.9 mol C m−2 yr−1. This suggests that the biomass of the primary producers is restricted by phosphorus availability. Phosphorus retention in the sediment and the hypersaline state of the lagoon prevent changes in autotrophic communities and the formation of eutrophic conditions.  相似文献   

12.
Inorganic nutrient contents of mucus released by Acropora corals and its utilization by heterotrophic bacteria at several different hour intervals in the coral mucus were investigated at a coral reef in Malaysia. The dissolved inorganic phosphate (DIP) concentration was 135‐fold higher than in the ambient seawater, probably due to inorganic P release from the coral gut cavity. We experimentally confirmed that heterotrophic bacteria rapidly (within 8 h) consumed ca. 80% of the initial concentration of DIP derived from coral mucus. High DIP concentration in coral mucus may enhance heterotrophic bacterial production and associated carbon flow in the microbial loop of reef ecosystems.  相似文献   

13.
于1998年10号台风、2000年10号台风碧利斯和2000年6月厦门地区特大暴雨影响期间。在厦门港湾对表层海水溶解无机氮(DIN)、溶解无机磷(DIP)以及盐度、DO、Chla等相关环境因子进行定点连续观测。描述了台风暴雨期间和恢复期DIN、DIP的变化特征。对水动力因素、底质再悬浮、有机物氧化降解及生物活动等因素的影响进行了初步的探讨。  相似文献   

14.
Based on a hydrodynamic-ecological model, the temperature, salinity, current, phytoplankton(Chl a),zooplankton, and nutrient(dissolved inorganic nitrogen, DIN, and dissolved inorganic phosphorous, DIP)distributions in the Beibu Gulf were simulated and the nutrient budget of 2015 was quantitatively analyzed. The simulated results show that interface processes and monsoons significantly influence the ecological processes in the gulf. The concentrations of DIN, DIP, phytoplankton and zooplankton are generally higher in the eastern and northern gulf than that in the western and southern gulf. The key regions affected by ecological processes are the Qiongzhou Strait in winter and autumn and the estuaries along the Guangxi coast and the Red River in summer.In most of the studied domains, biochemical processes contribute more to the nutrient budget than do physical processes, and the DIN and DIP increase over the year. Phytoplankton plays an important role in the nutrient budget; phytoplankton photosynthetic uptake is the nutrient sink, phytoplankton dead cellular release is the largest source of DIN, and phytoplankton respiration is the largest source of DIP. The nutrient flux in the connected sections of the Beibu Gulf and open South China Sea(SCS) inflows from the east and outflows to the south. There are 113 709 t of DIN and 5 277 t of DIP imported from the open SCS to the gulf year-around.  相似文献   

15.
长棘海星暴发对珊瑚礁生态系统产生了严重危害,而水体营养盐的补充可能是导致长棘海星暴发的一个关键因素。砂质沉积物对调控珊瑚礁区的营养盐浓度和结构起着关键作用,因此本研究通过流动式反应器对长棘海星和砂质沉积物进行模拟实验,分析长棘海星排泄活动及其死亡后有机体降解对水体营养盐的影响,并探究砂质沉积物的响应。实验结果表明:(1)长棘海星排泄的溶解无机氮(DIN)和溶解无机磷(DIP)通量分别为(83.55±4.74)μmol/(ind.·h)和(2.53±0.03)μmol/(ind.·h),这些营养盐可能给长棘海星的持续暴发提供营养条件;(2)砂质沉积物对长棘海星排泄导致的营养盐浓度升高具有缓冲作用,约70.7%的DIN和91.4%的DIP被截留在沉积物中,但沉积物界面营养盐交换导致的氮磷比升高可能不利于珊瑚生长;(3)长棘海星死后的有机体降解可促使沉积物–水界面释放营养盐,结合海星暴发密度估算,其释放的营养盐可导致上覆水中DIN和DIP浓度分别升高0.32 μmol/L和0.01 μmol/L,这可能会促使大型藻的快速生长而妨碍珊瑚的自我修复。  相似文献   

16.
The temporal and spatial variability of dissolved inorganic phosphate (DIP), nitrogen (DIN), carbon (DIC) and dissolved organic carbon (DOC) were studied in order to determine the net ecosystem metabolism (NEM) of San Diego Bay (SDB), a Mediterranean-climate lagoon. A series of four sampling campaigns were carried out during the rainy (January 2000) and the dry (August 2000 and May and September 2001) seasons. During the dry season, temperature, salinity and DIP, DIC and DOC concentrations increased from oceanic values in the outer bay to higher values at the innermost end of the bay. DIP, DIC and DOC concentrations showed a clear offset from conservative mixing implying production of these dissolved materials inside the bay. During the rainy season, DIP and DOC increased to the head, whereas salinity decreased toward the mouth due to land runoff and river discharges. The distributions of DIP and DOC also showed a deviation from conservative mixing in this season, implying a net addition of these dissolved materials during estuarine mixing within the bay. Mass balance calculations showed that SDB consistently exported DIP (2.8–9.8 × 103 mol P d−1), DIC (263–352 × 103 mol C d−1) and DOC (198–1233 × 103 mol C d−1), whereas DIN (5.5–18.2 × 103 mol N d−1) was exported in all samplings except in May 2001 when it was imported (8.6 × 103 mol N d−1). The DIP, DIC and DOC export rates along with the strong relationship between DIP, DIC or DOC and salinity suggest that intense tidal mixing plays an important role in controlling their distributions and that SDB is a source of nutrients and DOC to the Southern California Bight. Furthermore, NEM ranged from −8.1 ± 1.8 mmol C m−2 d−1 in September to −13.5 ± 5.8 mmol C m−2 d−1 in January, highlighting the heterotrophic character of SDB. In order to explain the net heterotrophy of this system, we postulate that phytoplankton-derived particulate organic matter, stimulated by upwelling processes in the adjacent coastal waters, is transported into the bay, retained and then remineralized within the system. Our results were compared with those reported for the heterotrophic hypersaline coastal lagoons located in the semi-arid coast of California–Baja California, and with those autotrophic hypersaline systems found in the semi-arid areas of Australia. We point out that the balance between autotrophy and heterotrophy in inverse estuaries is dependent on net external inputs of either inorganic nutrients or organic matter as it has been indicated for positive estuaries.  相似文献   

17.
李宁  王江涛 《海洋科学》2011,35(8):5-10
根据2010年4月在东海北部近岸的调查,分析了研究海域溶解无机碳(DIC)和溶解有机碳(DOC)的含量及其分布状况,并分别对DIC、DOC与温度、盐度、表观耗氧量等要素的关系进行了初步探讨。结果表明,春季研究海域表、底层DIC平均含量分别为24.54mg/L和25.03mg/L,平面分布趋势均为近岸高于远岸,象山口附近...  相似文献   

18.
We conducted hydrographic observations ten times in the Tsushima Strait to reveal seasonal variations of horizontal material transports such as of heat, freshwater, chlorophyll a, and dissolved inorganic nitrogen (DIN) and phosphorus (DIP) through the eastern channel of the Tsushima Strait (ECTS). The volume, freshwater, and heat transport results are of nearly the same order as results reported in previous studies. The annual mean DIN and DIP transports of 3.59 kmol/s and 0.29 kmol/s are large relative to those of the Changjiang and the Taiwan Strait and are horizontally transported through the ECTS. Nutrient transports are high in July–August and October and low in April and November. Increased nutrient transports in July–August and October are due to the appearance of a cold saline water mass in the bottom layer of the ECTS. Changes in DIN transports in summer and autumn, which account for two-thirds of the total annual DIN transport, would have a large effect on the nitrogen budget and biological productivity in the Tsushima Warm Current region.  相似文献   

19.
We examined the contribution of submarine groundwater discharge (SGD) to nutrient budgets in Hwasun Bay, Jeju Island, Korea in August 2009, October 2014, and May 2015. The concentrations of dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) in fresh groundwater were in the range of 285?716 μM and 2.3?3.2 μM, respectively, which were each 1?2 orders of magnitude higher than those in the bay seawater. The outer-bay seawater flowing into the bay was oligotrophic (2.9 ± 1.9 μM for DIN and 0.2 ± 0.3 μM for DIP). Nutrient budget calculations were performed for each season by accounting for submarine fresh groundwater discharge (SFGD) and water residence times. In August 2009 (DIN = 1.8 μM and DIN:DIP ratio = 4.6 for the outerbay water), DIN inputs from SFGD accounted for approximately 40% of the DIN inventory in the bay seawater. In October 2014 (DIN = 1.1 μM and DIP < 0.05 μM for the outer-bay water), DIP from SFGD accounted for approximately 100% of the DIP inventory in the bay seawater. In May 2015, mean concentrations of DIN and DIP in the bay seawater were 8.6 ± 12 μM and 0.11 ± 0.04 μM, respectively, with conservative behaviors in the bay seawater in association with excessive groundwater inputs. These results imply that SGD plays a critical but different role in nutrient budgets and stoichiometry in coastal waters off a volcanic island depending on open-ocean nutrient conditions.  相似文献   

20.
Seasonal variations in freshwater, salt, dissolved inorganic phosphorus (DIP) and dissolved inorganic nitrogen (DIN) in the Bangpakong estuary, Thailand were investigated by employing the database obtained in the National Research Council of Thailand (NRCT)-Japan Society for the Promotion of Science (JSPS) cooperative project from 1994 to 1997. The results showed that variation in interaction between coastal sea and river discharge played an important role in controlling the characteristics of the water in the estuary. Residence time of fresh water was short in wet season and dry season, but it was long in the transition period from season to season. DIP and DIN load depended on river discharge, while high peak concentrations were related to loading and the long residence time in the transition period between dry and wet seasons. A strong eutrophic condition could possibly occur when the concentration of DIP and DIN were high during the onset of the wet season from April to July. The annual average of inorganic nutrient budgets indicated that the Bangpakong estuary is the internal source of 38.2 tons/month DIP and the internal sink of 4.9 tons/month DIN. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号