渤海湾天津近岸海域水环境空间变异分析

由于海岸带的地理条件和海洋动力特性的复杂性以及人类开发活动对海岸带的影响,近岸海域的生态环境系统在空间分布上有很大的变异性.基于现场实测资料,建立系统的空间变异分析模型,对海岸带生态环境空间变化规律进行分析,可以充分了解不同区域的污染特征和变化趋势.应用所构建的空间变异分析模型对渤海湾天津近岸海域的水环境特性进行分析,结合对应年份的入海流量及其变化,分析了天津渤海湾海岸带污染的主因子和区域水环境的分布特征,结果可以对海洋功能区的划分和水环境综合评价结果进行验证和补充.     

盐度和营养限制对蓝杆藻(Cyanothece. sp)113菌株生长和胞外多糖产量的影响

蓝杆藻113菌株为海洋微藻，实验室培养证明其单位体积胞外多糖产量高。用改进的F／2改良培养液培养，添加70g／L时的NaCl盐度是该菌株胞外多糖释放的最适盐度。不添加NaCl时的盐度是菌体细胞生长的最适盐度。NaNO2营养限制抑制该菌株细胞的生长，促进该菌株胞外多糖的释放。NaH2PO4营养限制抑制该菌株细胞的生长，但对胞外多糖产量的影响不明显。MgSO4营养限制则同时抑制该菌株细胞生长和胞外多糖释放。该研究结果有助于蓝杆藻113菌株胞外多糖的生产及该菌株其它方面的开发利用。     

A depocenter of organic matter at 7800 m depth in the SE Pacific Ocean

The Atacama trench, the deepest ecosystem of the southern Pacific Ocean (ca. 8000 m depth) was investigated during the Atacama Trench International Expedition. Sediments, collected at three bathyal stations (1040–1355 m depth) and at a hadal site (7800 m) were analyzed for organic matter quantity and biochemical composition (in terms of phytopigments, proteins, carbohydrates and lipids), bacterial abundance, biomass and carbon production and extracellular enzymatic activities. Functional chlorophyll-a (18.0±0.10 mg m⁻²), phytodetritus (322.2 mg m⁻²) and labile organic carbon (16.9±4.3 g C m⁻²) deposited on surface sediments at hadal depth (7800 m) reached concentrations similar to those encountered in highly productive shallow coastal areas. High values of bacterial C production and aminopeptidase activity were also measured (at in situ temperature and 1 atm). The chemical analyses of the Atacama hadal sediments indicate that this trench behaves as a deep oceanic trap for organic material. We hypothesize that, despite the extreme physical conditions, benthic microbial processes might be accelerated as a result of the organic enrichment.     

The European coastal zone: characterization and first assessment of ecosystem metabolism

The geomorphic, oceanographic, terrestrial and anthropogenic attributes of the European coastal zone are described and published data on ecosystem function (primary production and respiration) are reviewed. Four regions are considered: the Baltic Sea, Mediterranean Sea, Black Sea and the European Atlantic coast including the North Sea. The metabolic database (194 papers) suffers from a non-homogeneous geographical coverage with no usable data for the Black Sea which was therefore excluded from this part of our study. Pelagic gross primary production in European open shelves is, by far, the most documented parameter with an estimated mean of 41 mmol C m⁻² d⁻¹, the lowest value is reported in the Mediterranean Sea (21 mmol C m⁻² d⁻¹) and the highest one in the Atlantic/North Sea area (51 mmol C m⁻² d⁻¹). Microphytobenthic primary production, mostly measured in shallow areas, is extrapolated to the entire 0–200 m depth range. Its contribution to total primary production is low in all regions (mean: 1.5 mmol C m⁻² d⁻¹). Although macrophyte beds are very productive, a regional production estimate is not provided in this study because their geographical distribution along the European coastline remains unknown. Measurements of pelagic community respiration are clearly too sparse, especially below the euphotic zone, to yield an accurate picture of the fate of organic matter produced in the water column. With a mean value of 17 mmol C m⁻² d⁻¹, benthic community respiration consumes approximately 40% of the pelagic organic matter production. Estuaries generally exhibit high metabolic rates and a large range of variation in all parameters, except microphytobenthic primary production. Finally, the problem of eutrophication in Europe is discussed and the metabolic data obtained in the framework of the Land–Ocean Interactions in the Coastal Zone (LOICZ) project are compared with available direct measurements of net ecosystem production.     

Biokarst on Limestone Coasts, Morphogenesis and Sediment Production

Abstract. Biokarst-forms on limestone coasts are developed and arranged according to the bionomic zonation. The development of biokarst is the result of bioerosion, a synergistic effect of biological corrosion by endoliths and biological abrasion by grazers.
The cumulative effect of biogenic carbonate destruction leads to coastal destruction with a resulting highly profiled morphology on the limestone surfaces along the coastal profile. Under the influence of environmental factors a zonation of organisms develops which brings in turn a zonation of erosion rates (0.1-1.1 mm a^-1) resulting in biokarst-forms such as rock holes, rock pools and notches.
Products of bioerosion on limestone coasts are dissolved carbonate (by biological corrosion, 10–30% of the decomposed limestone) and particulate carbonate (by biological abrasion, 70–90% of the decomposed limestone) both of which contribute directly or indirectly to nearshore sedimentation. Size and shape of the bioerosional grains are determined by the boring pattern of the endoliths. The fine-grained sediments (maximum within the fraction 20–63 μm) contribute 3–25 % to the nearshore sediments.
Drastic changes in the biological zonation (like the mass invasion of the sea urchin Paracentrotus lividus in the Northern Adriatic since 1972 which eliminated nearly the entire macrophyte zone) due to unknown factors or pollution can have a profound effect on the bioerosion rates, altering them by as much as a factor of ten.     

Correspondence between the distribution of hydrodynamic time parameters and the distribution of biological and chemical variables in a semi-enclosed coral reef lagoon

Hydrodynamic modeling can be used to spatially characterize water renewal rates in coastal ecosystems. Using a hydrodynamic model implemented over the semi-enclosed Southwest coral lagoon of New Caledonia, a recent study computed the flushing lag as the minimum time required for a particle coming from outside the lagoon (open ocean) to reach a specific station [Jouon, A., Douillet, P., Ouillon, S., Fraunié, P., 2006. Calculations of hydrodynamic time parameters in a semi-opened coastal zone using a 3D hydrodynamic model. Continental Shelf Research 26, 1395–1415]. Local e-flushing time was calculated as the time requested to reach a local grid mesh concentration of 1/e from the precedent step. Here we present an attempt to connect physical forcing to biogeochemical functioning of this coastal ecosystem. An array of stations, located in the lagoonal channel as well as in several bays under anthropogenic influence, was sampled during three cruises. We then tested the statistical relationships between the distribution of flushing indices and those of biological and chemical variables. Among the variables tested, silicate, chlorophyll a and bacterial biomass production present the highest correlations with flushing indices. Correlations are higher with local e-flushing times than with flushing lags or the sum of these two indices. In the bays, these variables often deviate from the relationships determined in the main lagoon channel. In the three bays receiving significant riverine inputs, silicate is well above the regression line, whereas data from the bay receiving almost insignificant freshwater inputs generally fit the lagoon channel regressions. Moreover, in the three bays receiving important urban and industrial effluents, chlorophyll a and bacterial production of biomass generally display values exceeding the lagoon channel regression trends whereas in the bay under moderate anthropogenic influence values follow the regressions obtained in the lagoon channel. The South West lagoon of New Caledonia can hence be viewed as a coastal mesotrophic ecosystem that is flushed by oligotrophic oceanic waters which subsequently replace the lagoonal waters with water considerably impoverished in resources for microbial growth. This flushing was high enough during the periods of study to influence the distribution of phytoplankton biomass, bacterial production of biomass and silicate concentrations in the lagoon channel as well as in some of the bay areas.     

Comparison of bromodeoxyuridine immunoassay with tritiated thymidine radioassay for measuring bacterial productivity in oceanic waters

Recently, bromodeoxyuridine (BrdU) has been successfully applied to the measurement of bacterial productivity as an alternative to tritiated thymidine (³H-TdR), which is widely used but often restricted by regulations, particularly in field settings. Here, I report improvements to existing BrdU methods to simplify procedures and increase sensitivity. The feasibility of the method was tested measuring bacterial production in low-productive waters. The method provided radioisotope-free measurements of bacterial production rates at shorter (∼1 h) on-board processing time of samples than previously reported procedures. It was applicable to the detection of rates ranging from 0.021 to 2.7 pmol BrdU l⁻¹h⁻¹. BrdU incorporation rates measured by immunoassay showed a statistically significant correlation with ³H-TdR incorporation rates measured by radioassay (r = 0.74, n = 24, p < 0.001). The linear regression obtained (BrdU = 0.80[³H-TdR] − 0.016) showed a similar relationship to previously reported regressions (BrdU = 0.65[³H-TdR] + 0.12, [³H-BrdU] = 0.69[³H-TdR] − 0.81). There were no statistically significant differences among these regression lines. These results suggest that the method described here provides a non-radioisotopic productivity measurement of bacteria in oceanic epipelagic waters, while retaining continuity of the data with other existing ³H-TdR and BrdU methods.     

汶川抗震救灾的基础地理信息综合应急服务

在5．12汶川特大地震抗震救灾中,国家测绘部门设计和组织实施了以数据成果服务、专用系统服务和专题制图服务为核心的基础地理信息综合应急服务。其是针对汶川震区地形特点和抗震救灾主体工作需求,快速整合和提供震区已有的基础测绘成果和最新遥感影像资料;快速搭建集震区海量数据集成管理为一体并具备3维影像浏览、对比分析等功能的专用地理信息系统,为灾情评估分析和重建规划研究提供地理空间数据集成展示和分析平台;应需地制作反映受灾范围、受灾程度、救灾响应、规划思路等的各类专题地图和地图集,有效地表达地震灾害的时空分布、重建规划布局等。