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1.
Seagrass habitats are structurally complex ecosystems, which support high productivity and biodiversity. In temperate systems the density of seagrass may change seasonally, and this may influence the associated fish and invertebrate community. Little is known about the role of seagrass beds as possible nursery areas for fish and invertebrates in China. To study the functioning of a seagrass habitat in northern China, demersal fish and invertebrates were collected monthly using traps, from February 2009 to January 2010. The density, leaf length and biomass of the dominant seagrass Zostera marina and water temperature were also measured. The study was conducted in a Seagrass Natural Reserve(SNR) on the eastern coast of the Shandong Peninsula, China. A total of 22 fish species and five invertebrate species were recorded over the year. The dominant fish species were Synechogobius ommaturus, Sebastes schlegelii, Pholis fangi, Pagrus major and Hexagrammos otakii and these species accounted for 87% of the total number of fish. The dominant invertebrate species were Charybdis japonica and Octopus variabilis and these accounted for 98% of the total abundance of invertebrates. There was high temporal variation in species composition and abundance. The peak number of fish species occurred in August–October 2009, while the number of individual fish and biomass was highest during November 2009. Invertebrate numbers and biomass was highest in March, April, July and September 2009. Temporal changes in species abundance of fishes and invertebrates corresponded with changes in the shoot density and leaf length of the seagrass, Zostera marina.  相似文献   

2.
依据西秦岭地区泥盆纪古生物及沉积相资料,本文将这一地区泥盆系划分为北秦岭生物区、华南生物区两个古生物区系,提出了北秦岭区沉积发展史以“D_m”事件为标志经历了两个重要阶段和古地理演变的四个期次,并认为大草滩群属华北大陆边缘沉积。  相似文献   

3.
Seagrass decline caused by the macroalgae blooms is becoming a common phenomenon throughout temperate and tropical regions. We summarized the incidence of macroalgae blooms throughout the world and their impact on seagrass beds by direct and indirect ways. The competition for living space and using resources is the most direct effect on seagrass beds when macroalgae are blooming in an aquatic ecosystem. The consequence of macroalgae blooms (e.g., light reduction, hypoxia, and decomposition) can produce significant indirect effects on seagrass beds. Light reduction by the macroalgae can decrease the growth and recruitment of seagrasses, and decomposition of macroalgae mats can increase the anoxic and eutrophic conditions, which can further constrict the seagrass growth. Meanwhile, the presence of seagrass shoots can provide substrate for the macroalgae blooms. Controlling nutrient sources from the land to coastal waters is a general efficient way for coastal management. Researching into the synergistical effect of climate change and anthropognic nutrient loads on the interaction between searsasses and macroalgae can provide valuable information to decrease the negative effects of macroalgae blooms on seagrasses in eutrophic areas.  相似文献   

4.
Understanding the dynamics of urbanization is essential to the sustainable development of cities. Meanwhile the analysis of urban development can also provide scientifically and effective information for decision-making. With the long-term Defense Meteorological Satellite Program’s Operational Linescan System(DMSP/OLS) nighttime light images, a pixel level assessment of urbanization of China from 1992 to 2013 was conducted in this study, and the spatio-temporal dynamics and future trends of urban development were fully detected. The results showed that the urbanization and urban dynamics of China experienced drastic fluctuations from 1992 to 2013, especially for those in the coastal and metropolitan areas. From a regional perspective, it was found that the urban dynamics and increasing trends in North Coast China, East Coast China and South Coast China were much more stable and significant than that in other regions. Moreover, with the sustainability estimating of nighttime light dynamics, the regional agglomeration trends of urban regions were also detected. The light intensity in nearly 50% of lighted pixels may continuously decrease in the future, indicating a severe situation of urbanization within these regions. In this study, The results revealed in this study can provided a new insight in long time urbanization detecting and is thus beneficial to the better understanding of trends and dynamics of urban development.  相似文献   

5.
论辽南上前寒武系的划分与对比   总被引:1,自引:0,他引:1  
辽南上元古界的区域对比的关键是如何与蓟县层型、峡东层型的衔接或对比。作者认为辽南群是介于北方的青白口群与南方的震旦系之间的层位,仅金县群才相当于震旦系,震旦系与寒武系的界线则应置于兴民村组与葛屯组之间。  相似文献   

6.
????GRACE????????2002??4??~2004??7?1???20???μ??????????????????????й???????????????????仯???????y????????????????????CPC??????????????????????????????:GRACE????????????????????????????????:???????????????????????????????仯??????12??14 cm????????????С??????????????????????????仯??????????8 cm???????????????????????????仯??С?????????????????????GRACE???????????????????  相似文献   

7.
浅谈南海渔业管理对策   总被引:2,自引:0,他引:2  
南海渔业资源衰退的主要原因是捕捞过度和海洋生态环境破坏。由于海洋生态过程是动力学过程,很多生态因素的变化会相应引起生态过程的变化,同时生态动力学过程的因素又是多方面的,因此南海渔业资源的管理和生产方式应该从过去的开发型管理向着管理型管理方向转变。这种管理方式涉及面较广,必须实施从渔业资源管理、渔业水域管理、渔业水域周围环境管理到加强对渔船与船员管理、捕养并重、健全法制、强化治政队伍与执法力量配置以及开展国际渔业合作等管理措施。  相似文献   

8.
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass (Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) (P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 (P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination rate at 14°C (P<0.001). Although significant interaction was found between temperature and salinity (P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China.  相似文献   

9.
中国生态环境遥感四十年   总被引:2,自引:0,他引:2  
生态环境是人类社会生存与发展的基础。快速发展的遥感技术显著推动着生态环境遥感监测能力的提升,有效支撑了国家生态文明建设。从1980年天津—渤海湾环境遥感试验开始,经历了近40年的发展,遥感监测技术已经广泛应用于生态、大气、水、土壤等生态环境保护各个方面,取得显著成效。本文回顾了我国生态环境遥感技术近40年的发展,通过典型或重要应用案例,系统梳理了遥感技术在生态环境监测、对地观测能力、支撑生态文明建设等方面应用的发展历程。生态环境遥感监测能力发展主要表现在应用领域逐步扩大、监测精度明显提升、监测时效大幅增强;对地观测能力发展主要分为国外卫星为主期、环境卫星发展期、高分卫星应用期3个阶段;支撑生态文明建设的重大事件主要包括全国生态状况定期调查评估、污染防治攻坚战、应急与监督执法等方面。本文结合国家战略和技术发展,对今后生态环境遥感的发展提出了一些思考。  相似文献   

10.
CHARACTERISTICS AND CONSTRUCTION OF LANDSCAPE ECOLOGY IN ARID REGIONS   总被引:1,自引:0,他引:1  
Landscapeecologyisanewinterdisciplinarysci encedealingwiththeinteractionsbetweenspatialpat ternsandecologicalprocesses.Theapplicationofthelandscapeconceptionisgenerallybasedontheterrito riesofhumanscaleorregardedastherepresentativeofspatialheterogeneit…  相似文献   

11.
《山海经》中的“东山”区位地理考古研究   总被引:1,自引:1,他引:0  
《山海经》是一部中国最古老的地理著作。其中“五藏山经”篇中所讲的西、南、北、中山都分布在中国大陆,只有东山的记述在国内一直找不到,三千多年来我国古书上多“无注”或称“其山水无可考”。美国女学者亨利埃特·默茨(HenrietteMertz)通过实地考察后所写的《淡淡的墨迹(Palegnk-TosoOreientRecordsofChineseExplorationinAmerica1953)》证明“东山”海外部分竟分布在美洲大陆,它们就是落基山脉、内华达山脉、喀斯喀特山脉以及海岸山脉,它们的距离,山峰数与动植物的种类与《山海经》记载的都基本相同。该书主题提示这样写的:“《山海经》-印第安人-中国的影响-美洲-中国人的发现和探索”。书中结语还特别强调:“对于在4000年左右,就已踏着白雪皑皑的山顶和峻峭的山峰而徒步考察无畏的中国人后面,我们所能做的,首先要向他们顶礼膜拜、鞠躬致敬。”  相似文献   

12.
From the angle of ecology, urban agglomeration presents relevant types of landscape structure, which in-clude Patch, Corridor and Matrix. There are different landscape features and different problems in different developmentphases. This paper has put forward five basic conditions for security pattern of landscape ecology of urban agglomeration,described quantitatively the features for landscape ecology in Wuxi, and analyzed ecological background of spatial expan-sion and spatial organization of urban development in Wuxi. From the angle of ecological land use and non-ecological landuse, the paper has analyzed the features of land use and ecological distribution of land in the urban area. The spatial mod-el of cities and towns in Wuxi is composed of one metropolis, two urban zones and three development axes. This thesishas planned preliminarily ecological protection network at four levels in the urban region according to four layers. At last,combining landscape ecology with urban space, a tentative security pattern of landscape ecology has been planned in Wux-i, namely Source-Buffer Zone and Metropolis, Radiating Routes and Expansion Direction of City, Strategic Point and Interac-tion between Cities and Towns, Inter-Source Linkage-Corridor of a Stable Landscape Structure.  相似文献   

13.
基于SOFM网络的景观功能分类——以北京及周边地区为例   总被引:3,自引:0,他引:3  
 景观多功能性是景观生态学研究的热点领域,需要一种既能体现景观多功能整体性,又能表征各功能间独立性的表达方法。本文以北京及其周边地区为研究区,以500m栅格为最小评价单元,使用空间化的统计数据表征物质生产功能,使用植被生物量与土壤含碳量之和表征碳汇功能,使用潜在水土流失量与实际水土流失量的差值表征土壤保持功能,使用生态系统服务功能的评估结果表征生境维持功能,使用人口空间化数据表征居住功能。在计算5种景观功能强度后,通过自组织特征映射模型将土地栅格进行聚类分析。研究结果表明:景观功能强度具有空间异质性。景观功能强度可分为以农地为优势景观,以物质生产为主要功能的农业功能区域;以农地和城市用地为优势景观,以居住和碳汇为主要功能的城市功能区域;以林草地为优势景观,以土壤保持和生境维持为主要功能的生态功能区域;以及优势景观不明显,各项功能均衡发展的过渡功能区域4类。该分类方法既可较好地表达多功能景观的功能分异和空间分异,又能为其研究土地利用和生态管理实践提供理论依据。  相似文献   

14.
???й?????????????????????????????????5?????壬????????????????С???????÷?????С?????????????????????3????????????????о??й?????????????????????????????????????????????????????С???????÷????????壨??????????????????壩????????????????????|?????????????????????????????????????????????????С???????÷?????й????1°×1°?????????????????????????????????С??  相似文献   

15.
将中国大陆划分成东北、华北、华南、青藏、西北5个块体,基于克里金插值法、最小二乘配置法、最小二乘配置移动拟合推估法等3种方法及速度场数据研究中国大陆速度场模型建立方法。利用外检点分析不同建模方法的精度情况,最小二乘配置法在大部分块体(华北、华南、东北块体)的拟合精度都较高,表现稳定|克里金插值法在青藏、华北块体的拟合精度较高。利用克里金插值法与最小二乘配置法获取中国大陆1°×1°格网中心点速度场成果,两种方法成果差异较小。  相似文献   

16.
华北北部地区震源机制解及构造应力场特征分析   总被引:1,自引:0,他引:1  
利用华北北部地区2002 01—2010 06月848个Ml≥2.0地震的震源机制解,根据区域构造活动特征将其划分为4个研究区,分析各研究区震源机制解特征,并采用1°×1°的网格,0.5°滑动分区的方法对华北北部地区各研究区和空间滑动进行应力场特征研究。结果表明,各研究区的最大主应力的方位为NEE向,最小主应力方位为NNW向,与华北地区区域构造应力场方向较一致。各研究区的应力结构均为走滑型,水平应力作用为华北北部地区构造应力场的主要特征,震源错动方式以水平走滑为主。  相似文献   

17.
The orogenic belt locates between the North China plate and Siberia plate. The Permian palaeobiogeography and tectonic palaeogeography changed quickly and clearly. The line from Changchun to Yanji is an important palaeobiogeographic provincing line, which may be the collission suture belt of the North China plate and north middle massifs. The orogenic belt has been divided into 2 regions: the North middle massif region and the North Margin of North China plate, the pattern and evolution of Permian palaeobiogeography in the present area were discussed and the Permian biota mixture and its significants were analysed. Then, Based on the above, the Permian tectonic palaeogeography of the orogenic belt is reconstructed.  相似文献   

18.
应用1979.1-2006.12北太平洋海表温度(SST)资料,采用一元线性回归、功率谱等统计方法对该区SST的变化特征进行分析,结果表明:(1)北太平洋SST年际变化较为显著,尤其在靠近亚洲大陆一带洋面、北太平洋中部中纬度海域及赤道中、东太平洋;(2)北太平洋西部和中部SST1-12月均呈上升趋势,靠近亚洲大陆的日本海一带和我国大陆以东洋面升温最快。除我国以东洋面升温中心在冬季外,其余海域升温均在夏秋季更迅速,20世纪90年代初以来尤为明显;北美海岸山脉以西及赤道中、东太平洋SST则呈弱的下降趋势;(3)赤道中、东太平洋春夏季存在显著5a和3.5a左右的年际变化;北太平洋中部30°N一带冬春季存在5-6a左右的年际变化和约14a的年代际变化;(4)除北太平洋中部(西风漂流区)外,各个海域大部分月份SST高值年和低值年分别与厄尔尼诺年和拉尼娜年对应,西风漂流区SST高值年均出现在20世纪末21世纪初,低值年与厄尔尼诺年对应。  相似文献   

19.
Land use regionalization of rural settlements in China   总被引:2,自引:1,他引:1  
This paper compartmentalizes regional land use of rural settlements in China by employing a hierarchical clustering method.The statistic data are sourced from the National Bureau of Statistics of China(NBSC) and the data of land use change from the Ministry of Land and Resources of China(MLRC).The population of rural settlement decreases from the southeast to the northwest of China and the density of rural settlement decreases from the east to the west of China.Land-use scale of rural settlement,the proportion of one-storey houses and the average household area decrease from the north to the south of China.The ratio of area of cultivated land to rural settlement is high in the northeast and southwest of China but low in the southeast of China.The land use regionalization of rural settlement can be divided into four regions,namely:the northern region of China,Qinghai-Tibet,Yunnan-Guizhou,and the middle and eastern region of China.The northern region of China and the middle and eastern region of China can be further divided into nine sub-regions:Xinjiang,Northeast China,Ningxia and Inner Mongolia,North China,the south of the Changjiang(Yantze) River and Sichuan Basin,Jiangsu-Shanghai,South China,the Loess Plateau,and Guangxi.In consideration of the significant regional differences,it is proposed that different policies should be implemented regarding the utilization and management of rural settlements.  相似文献   

20.
生态多样性(ecological diversity)是诸如物种和景观元等研究对象丰富性和空间分布均一性的综合,其多尺度测算与模拟已经成为生态学界研究的热点之一。其与传统多样性模型相比,Scaling生态多样性模型能够综合反映均一性和丰富性两个方面的多样性信息,同时考虑了空间尺度因素的作用,是一个理论上完美的生态多样性模型。利用Scaling生态多样性模型对中国西部地区三期遥感数据进行模拟,结果表明:①20世纪80年代末期-90年代末期,中国西部地区景观元多样性先减少后增加,其内部明显具有东高西低的空间分布规律;②省级行政区尺度上模拟结果说明陕西省景观元多样性最高,新疆维吾尔族自治区和西藏自治区最低;西藏自治区景观元多样性变化最显著,而甘肃省和重庆市变化最小;③县级行政区尺度上模拟结果发现中国西部地区存在11个景观元多样性的关键地区;④对比各尺度模拟结果,发现中国西部地区整体景观元多样性大于各省级行政区,各省级行政区大于省内县级行政区,说明Scaling多样性模型能够反映空间尺度因素与生态多样性间存在的正向相关关系。  相似文献   

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