Population‐specificity of heat stress gene induction in northern and southern eelgrass Zostera marina populations under simulated global warming

Summer heat waves have already resulted in mortality of coastal communities, including ecologically important seagrass meadows. Gene expression studies from controlled experiments can provide important insight as to how species/genotypes react to extreme events that will increase under global warming. In a common stress garden, we exposed three populations of eelgrass, Zostera marina, to extreme sea surface temperatures, simulating the 2003‐European heat wave. Populations came from locations widely differing in their thermal regime, two northern European locations [Ebeltoft (Kattegat), Doverodde (Limfjord, Baltic Sea)], and one southern population from Gabicce Mare (Adriatic Sea), allowing to test for population specificity in the response to a realistic heat stress event. Eelgrass survival and growth as well as the expression of 12 stress associated candidate genes were assessed during and after the heat wave. Contrary to expectations, all populations suffered equally from 3 weeks of heat stress in terms of shoot loss. In contrast, populations markedly differed in multivariate measures of gene expression. While the gene expression profiles converged to pre‐stress values directly after the heat wave, stress correlated genes were upregulated again 4 weeks later, in line with the observed delay in shoot loss. Target genes had to be selected based on functional knowledge in terrestrial plants, nevertheless, 10/12 genes were induced relative to the control treatment at least once during the heat wave in the fully marine plant Z. marina. This study underlines the importance of realistic stress and recovery scenarios in studying the impact of predicted climate change.     

胶州湾海岸湿地维管束植物的区系特征与保护

胶州湾海岸湿地植被分4个主要植被型、15个主要植物群落,作为湿地植被建群种、优势种和主要伴生种的维管束植物共有35科61属75种,分盐生植物、水生植物、湿生植物和沙生植物4大生态类群。其中禾本科、黎科、蓼科等7个较大科的种子植物构成了胶州湾海岸湿地维管束植物区系的主体。从分布区类型构成看,胶州湾海岸湿地植物区系成分中世界分布属最多,达24属,占总属数的39.3%,这反映了湿地植被的隐域性特征。温带分布区成分和热带分布区成分作为区系成分的主体占总属数的52.4%。针对胶州湾海岸湿地发生的退化现象,提出了保护胶州湾海岸湿地维管束植物的初步措施。     

Comparative composition and dynamics of harmful dinoflagellates in Mediterranean salt marshes and nearby external marine waters

The taxonomic structure of phytoplankton populations in two Mediterranean coastal lagoons were compared with those of nearby marine waters (external waters). Mediterranean confined lagoons remain isolated for most the year and concentrate phytoplankton to a very high biomass. Coastal lagoons on the Mediterranean may, therefore, act as accumulators of neritic phytoplankton (including species related to harmful algal blooms). We examined whether coastal lagoons act as concentrators of marine toxic dinoflagellates during confinement periods, and the common environmental factors that favour growth of specific harmful species in the two ecosystems considered: coastal lagoons and external waters. An alternation between the dominance of diatoms and dinoflagellates was observed, coinciding with that described in Margalef's mandala, occurring in external waters as well as in coastal lagoons. Moreover, the temporal patter was different in the two ecosystems. Dinoflagellate species composition and their bloom period were highly variable in time and space, thus, species had to be analysed individually. Most of the dinoflagellate species found in this study were potentially harmful and high biomass producers. Harmful dinoflagellate species performed well in both, external waters and lagoons, but the specific species-dependent affinity to each of these environments determined which organisms bloom there. Thus, expansion of harmful algal blooms (HAB) to inland waters is not likely and some environmental factors such as the oxidised state of available nitrogen, became determinant to the success and bloom of a species in the coastal lagoon ecosystem.     

Range persistence during the last glacial maximum: Carex macrocephala was not restricted to glacial refugia

The distribution of many species inhabiting northwestern North America has been heavily influenced by the climatic changes during the late Pleistocene. Several studies have suggested that species were restricted to glacial refugia north and/or south of the continental ice sheet front. It is also hypothesized that the coast of northwestern North America could have been a prime location for glacial refugia because of the lowering of the eustatic sea level and the concomitant rise of the continental shelf because of tectonic rebound. Alternatively, some coastal species distributions and demographics may have been unaffected in the long-term by the last glacial maximum (LGM). We tested the glacial refugium hypothesis on an obligate coastal plant species, Carex macrocephala by sampling 600 individuals from 41 populations with 11 nuclear microsatellite loci and the rpL16 plastid intragenic spacer region. The microsatellite data sets suggest a low level of population differentiation with a standardized G '_ST = 0.032 and inbreeding was high with an F  =   0.969. The homogenization of the populations along the coast was supported by a principal coordinate analysis, amova s and samova analyses. Analyses using the rpL16 data set support the results of the microsatellite analyses, with a low F _ST of 0.042. Coalescent and mismatch analyses using rpL16 suggest that C. macrocephala has not gone through a significant bottleneck within the past 100 000 years, although a much earlier population expansion was indicated by the mismatch analysis. Carex macrocephala exhibits the characteristics of metapopulation dynamics and on the basis of these results, we concluded that it was not restricted to glacial refugia during the LGM, but that it existed as a large metapopulation.     

盐城自然保护区海滨湿地植被演替的生态机制

研究选取盐城自然保护区核心区典型湿地作为参照,对其海滨湿地植物群落的自然演替以及利用生态工程方法控制外来种互花米草(Spatina alterniflora)的生态学机理进行了研究.利用空间替代时间的方法,采取主分量分析和多元线性回归相结合的分析手段,对采集的相关环境参量数据进行分析,建立了海滨湿地植被自然演替的模型.模型表明,在海滨湿地植被的自然演替过程中,水分、盐度、土壤养分都起到了重要的作用,同时种间竞争也发挥了巨大的作用.不同演替阶段各因素的影响大小各不相同.在模型的基础上分析了演替过程中环境因子与3种主要优势物种之间以及物种与物种之间的相互作用关系.     

盐分和母树大小对黑松海防林种子萌发和幼苗早期生长的影响

研究了盐度(0、0.02、0.04和0.08 mol·L~(-1))和黑松母树大小对山东半岛北部海防林的主要造林树种黑松种子萌发和幼苗早期生长的影响.结果表明:盐度对黑松种子的发芽率有显著影响,随着NaCl浓度的升高,种子萌发率逐渐下降;盐分抑制黑松幼苗的早期生长,随着盐浓度升高,黑松幼苗的根长、芽长及根干质量均显著降低;母树大小在总体上对种子萌发率没有影响,但显著影响黑松幼苗的根长、芽长和芽干质量;盐度和母树大小的相互作用显著影响黑松幼苗的根长和芽长.而对黑松种子萌发率、幼苗根干质量和芽干质量的影响不显著.

Abstract：

Pinus thunbergii is the main forestation tree species of coastal protection forests in northern Shandong Peninsula of China. Its seed germination and seedling early growth were stud-ied under the conditions of different water salinity (0, 0. 02, 0. 04, and 0. 08 mol·L~(-1)) and mother tree sizes. With increasing sea water salinity, the seed germination rate, root-and plu-mule length, and the dry weights of root and plumule decreased significantly. Mother tree size had little effects on the seed germination rate, but affected the root-and plumule length and the plumule dry weight significantly. The interaction of sea water salinity and mother tree size affect-ed the root-and plumule length significantly, but less affected the germination rate and the dry weights of root and plumule.     

快速城市化阶段上海海岸带景观格局的时空动态

海岸带景观动态是海岸带综合管理的重要方面.本文利用多时相遥感影像解译的土地利用数据研究了1994-2005年快速城市化阶段上海海岸带的景观动态变化特征.结果表明:人类干扰导致了海岸带景观的破碎化程度增加,斑块隔离程度加大,景观多样性增大;海岸带基质景观(即农田)的面积持续减少,优势度明显降低,破碎化加大,反映城市化的人工景观类型(如工业用地、交通用地、公共设施用地、居住用地)面积不断增加,成为第二大景观类型,其他用地(主要是在建用地)的面积不断增加,显示出海岸带仍在经历快速城市化过程;导致海岸带景观变化的驱动力主要是国家政策、地方政府的决策、上海市的快速城市化,以及沿海大型开发项目(如浦东国际机场、洋山国际深水港、上海化学工业区等).在分析海岸带城市化带来的生态环境后果的基础上,建议实施综合海岸带管理以实现海岸带的可持续发展.

Abstract：

Coastal zone's landscape dynamics is recognized as one of the important aspects of in-tegrated coastal management. In this paper, the land use datasets derived from time series aerial images were employed to study the coastal landscape dynamics of Shanghai from 1994 to 2005, the period of rapid urbanization. During this period, human disturbances caused landscape frag-mentation and isolation, and increased landscape diversity. The area of main landscape (agricul-tural land) continued to decrease, its dominance declined, and became more fragmentation; while the areas of artificial landscapes reflecting urbanization (e.g.,lands for industry, traffic, public facility, and residence) increased, becoming the second dominant landscape type. The increasing area of other land uses (mainly constructing sites) implied that this coastal zone was still undergoing rapid urbanization. Central government policies, local government decision-mak-ing, rapid urbanization of Shanghai, and coastal big-scale development programs such as Pudong International Airport, Yangshan International Harbor, and Shanghai Chemical Industry Park were the main driving forces for these coastal landscape changes. Based on the analysis of the ecologi-cal consequences of this rapid urbanization, some suggestions for integrated management were made to promote the sustainable development of Shanghai coastal zone.     

Dynamics of dissolved O2, CO2, CH4, and N2O in a tropical coastal swamp in southern Thailand

We studied the distribution of dissolved O₂, CO₂, CH₄, and N₂O in a coastal swamp system in Thailand with the goal to characterize the dynamics of these gases within the system. The gas concentrations varied spatially and seasonally in both surface and ground waters. The entire system was a strong sourcefor CO₂ and CH₄, and a possible sink for atmospheric N₂O. Seasonal variation in precipitation primarily regulated the redox conditions in the system. However, distributions of CO₂, CH₄, and N₂O in the river that received swamp waters were not always in agreement with redox conditions indicated by dissolvedO₂ concentrations. Sulfate production through pyriteoxidation occurred in the swamp with thin peat layerunder aerobic conditions and was reflected by elevatedSO ₄ ^2– /Cl^– in the river water. When SO ₄ ^2– /Cl^– was high, CO₂ and CH₄ concentrations decreased, whereas the N₂O concentration increased. The excess SO ₄ ^2– in the river water was thus identified as a potential indicator for gas dynamics in this coastal swamp system.     

大丰沿海滩涂大匡围高水体养殖生态经济模式

大丰市自1992年至1997年在生态农业建设中,选择了本市沿海滩涂土地后备资源开发利用、改造和保护为重点的生态农业建设。大匡围高水体养殖生态经济模式的建立是一项新的突破,获得了环境、经济、社会效益的统一。现概述如下。1　大匡围高水体生态养殖工程大匡围高水体生态养殖工程模式是在全市沿海滩涂区以水改土,粗放型苇鱼养殖模式的基础上,改粗养为精养,提高产出,加速生态演替而成的。它充分利用原有苇鱼养殖的匡格堤埝,抬高水位,进行加土补堤,减少土方工程量,降低投资而设计的一种淡水养殖生态工程模式(图1)。1.1　土建工程圩堤,护坡工程…     

中国沿海的赤潮问题

统计了中国沿海１９７２～１９９８年的赤潮事件３６０起（香港、台湾省未统计在内）,系统介绍了中国赤潮研究概况和研究机构与组织。对中国沿海的赤潮进行分海区分析。根据海洋学特征,中国赤潮可分为：近岸型（河口和内湾型）、外海型（外洋型）、外来型（外源型）、养殖区型赤潮。根据中国近十多年来发生赤潮的现状,可归纳为４个特点：①频率增高;②持续时间长、范围广和危害增大;③新记录和有毒种类增多;④“双相型”赤潮有上升趋势、类型多样等。