Paradigmatic responses of marine benthic communities to different anthropogenic pressures, using M-AMBI, within the European Water Framework Directive

The use of AMBI and M-AMBI in benthic quality assessments, within the European Water Framework Directive (WFD), has increased dramatically in recent years. M-AMBI is a multivariate tool, which incorporates AMBI, richness and Shannon diversity within the assessment. The response of this approach to different human pressures in coastal and estuarine waters has been investigated for the Basque Country (Northern Spain). In this contribution, several paradigmatic examples of these applications to different water bodies are presented. The time-series extend to samples collected between 1995 and 2007, showing the evolution of M-AMBI values under different pressures, i.e. urban and industrial discharges, dredging and disposal of sediments, and engineering works (such as land reclamation or marina construction), and, in addition, for illustrating the benthic quality recovery after positive actions have been undertaken, i.e. the removal of point-source discharges or water treatment programmes. In most cases, M-AMBI responds to these pressures as expected, with decreases in the ecological status immediately following the pressure. Conversely, when a pressure is removed, the recovery takes between 2 and 15 years, depending upon the intensity of the pressure and the characteristics of the water body. M-AMBI has been intercalibrated previously in coastal waters. After intercalibration in transitional waters, M-AMBI will be able to be used in the integrative quality assessment of European water bodies.     

长江口盐沼湿地底栖微藻的分布特征及其对有机质产出的贡献

2006年6月(夏季)和12月(冬季)分别对长江口九段沙湿地潮滩底栖微藻的分布状况进行了调查,估算了湿地内各主要初级生产者的生产力并进行了比较。结果显示分布于该盐沼湿地的底栖微藻在光照条件下主要聚集于沉积物表层,形成其生物量随深度增加而迅速减少的垂直分布模式,并随滩面植被盖度从大到小的顺序呈现为:光滩、藨草区、米草区≈芦苇区的水平分布特征。九段沙湿地中单位面积上底栖微藻的生物量远高于上覆水中浮游植物的生物量,其单位面积生产力也显著高于后者,表明底栖微藻在源自单胞藻的湿地有机产出中占有主导地位。九段沙湿地中底栖微藻总生物量远低于地表维管植物,其生物量仅占潮滩初级生产者总生物量的约0.41%,所产出的有机质却达到潮滩总初级生产力约16.53%,意味着这种高营养、易摄取的有机产出有能力成为维持该湿地生态系统的重要食物来源之一。     

Prediction of hydrocarbon recovery from turbidite sandstones with linked-debrite facies: Numerical flow-simulation studies

A series of two-dimensional numerical flow simulations were carried out to investigate the production characteristics of a sheet sandstone bed with a linked-debrite interval. A deterministic geological model was used based on a two-dimensional representation of a bed from the Marnoso Arenacea Formation. The model was 60 km long and 1 m thick and contained three zones, arranged in a vertical facies arrangement typical of many linked-debrite beds: i) a lower, coarse-to-medium grained, clean turbidite sandstone interval; ii) a middle, muddy sandstone, debrite interval; iii) an upper, fine-grained, clean, laminated sandstone interval. Simulation involved only a 3-km long sector of the model, with one injector well and one production well, placed 1-km apart in the middle of the sector model. The simulated sector was moved progressively down the length of the bed, in 1-km steps, sampling different parts of the bed with different facies proportions. The petrophysical properties of the debrite interval were varied to produce different porosity–permeability cases. All other modelling parameters, including the upper and lower interval petrophysics, were kept constant. Results indicate that, in most cases, key production parameters such as cumulative oil production with time and water cut are proportional to the volume of movable oil between the wells. This relationship does not hold, however, for cases with relatively low values of debrite porosity (≤0.15) and permeability (k_h ≤ 100 mD) where the debrite interval accounts for more than 20% of the interwell volume. In these models, production efficiency declines systematically with reducing reservoir quality and increasing debrite percentage, resulting in relatively low oil production and early water breakthrough.     

Influence of giant kelp beds (Macrocystis pyrifera) on diel cycles of pCO2 and DIC in the Sub-Antarctic coastal area

The partial pressure of CO₂ (pCO₂) and dissolved inorganic carbon (DIC) were monitored in shallow coastal waters located inside and outside giant kelp beds (Macrocystis pyrifera) located in the Kerguelen Archipelago (Southern Ocean). Photosynthesis and respiration by microplankton and kelp lead to marked pCO₂ and DIC diel cycles. Daily variations of pCO₂ and DIC are significant in the spring and summer, but absent in the winter, reflecting the seasonal cycle of biological activity in the kelp beds. If the kelp beds seem to favour the onset of phytoplankton blooms, most of the primary production inside the kelp beds is due to the kelp itself. The primary production of Macrocystis kelp beds in the Sub-Antarctic high-nutrient, low-chlorophyll (HNLC) waters off the Kerguelen Archipelago is elevated and closely linked to light availability. This production is significant from October to March and reaches its climax in December at the solar radiation maximum.     

GIS技术在动物疫病防控中的应用

数字畜牧是动物卫生领域的重要发展趋势。本文着重讨论GIS技术在动物疫病防控中的应用,并以辽宁省畜禽分布定位及重大动物疫病防控调度指挥系统的建设为实例提出基于SuperMap GIS平台构建动物疫病防控系统的解决方案,从而为我国畜牧业信息化建设提供参考。     

山水实景演出的空间生产研究:以《桃花源记》实景演出为例

实景演出是国内旅游开发中文化旅游融合的典范.基于旅游表演理论和空间生产理论,通过参与观察和深度访谈等研究方法,以《桃花源记》为案例,探讨实景演出的空间生产机制,得出结论如下:①以桃花源景区和演出公司为主导,改造生产出物质空间,构成白天的景区游览空间;②通过灯光、音效、烟雾的效果将夜间的景区空间分割为前台和后台,在前台游...     

2012年楚科奇海及其邻近海域浮游植物现存量和初级生产力粒级结构研究

通过2012年夏季第五次北极科学考察期间在楚科奇海及其邻近海域现场调查所获得的数据分析研究了海域的粒度分级叶绿素a浓度和初级生产力。结果表明,叶绿素a浓度和初级生产力的高值均出现在楚科奇海陆架区,并且远高于深海区。去程时调查海域水层平均叶绿素a浓度的变化范围为0.32~15.66mg/m3,平均(2.77±3.96)mg/m3,高值区出现在南部邻近白令海峡海域、北部阿拉斯加巴罗近岸和冰缘区;初级生产力的范围为50.11~943.28mg/(m2d),高值出现在冰缘水华区。返程时水层平均叶绿素a浓度的变化范围为0.07~1.52mg/m3,平均(0.41±0.40)mg/m3,高值仍出现在陆架区,但比去程时低了一个数量级;初级生产力的分布范围为12.31~41.35mg/(m2d),高值出现在陆架区。浮游植物粒度分级测定结果表明,在生物量较低的深海区,叶绿素a浓度和初级生产力的粒级结构以微微型浮游生物(Pico级份)占优势(其贡献率分别为46.1%和56.9%),小型(Net级份)和微型(Nano级份)对总叶绿素a浓度的贡献差异极小,分别为26.6%和27.3%,对总初级生产力的贡献分别为23.8%和19.3%;而在生物量较高的水深小于200m的陆架区,Net级份叶绿素a浓度所占百分比最高,Pico级份次之,Nano级份最低,分别为59.8%、27.9%和12.3%,初级生产力的粒级结构中叶绿素a浓度所占百分比由高到低同样是Net、Pico和Nano,所占百分比分别为60.6%,32.2%和7.2%。     

带水凝析气藏采收率标定废弃条件确定

废弃产量和废弃压力是标定凝析气藏可采储量的重要参数。在一年一度可采储量标定工作中发现,目前所提及的废弃条件的确定方法对于带水凝析气藏而言或说法不确切,或计算方法不适应,或精度不高。根据多年可采储量标定的经验,针对东海带水凝析气藏实际情况,提出一套适应于东海地区带水凝析气藏废弃产量和废弃压力的确定方法,且以东海XX气藏YY井为例,结合油藏工程、采油工艺等专业,介绍计算方法具体运用,对于具有同样地质特征气藏具有一定的借鉴意义。     

省级基础测绘1∶10000 DLG生产工艺的优化

本文通过省级基础测绘DLG更新生产方法的研究,寻求一种高效率、高质量的生产流程,满足本轮基础测绘更新的要求。