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1.
A mire as an ecosystem, usually is considered as an aquatic ecosystem,or a terrestrial ecosystem. The author thinks that mire is a special ecosystem between these two ecosystems, and proposes the new concept that a mire is a natural ecosystem with transitional nature of semi-water and semi-land formed by water and land interaction. The paper discusses the nature of the mire ecosystem, the exploitation and utilization and ecological construction of a mire.  相似文献   

2.
FLOROGEOGRAPHYOFMIREPLANTSINSOUTHERNPARTOFQINGHAIXIZANGPLATEAUANDITSADJACENTAREASZhaoKuiyi(赵魁义)ChangchunInstituteofGeography...  相似文献   

3.
The southern part of the Qinghai-Xizang (Tibet) Plateau and its adjacent area are rich in mire flora. There are 51 families, 101 genera and 220 species. The geographical compositions of this region are very complex, consisting of the following-geographical elements: tropic-subtropic elements approximating to 8.33% of the entire flora in the region, tropic-temperate elements 22.71%, temperate elements 43.18%, cosmopolitan elements 9.85%, the Qinghai-Xizang endemic elements 14.39%, north polemountain elements 1.51%. Temperate elements in this region are dominant. The dominant species of mires, Carex lasiocarpa, in this region is also found in northeast China, Finland and North America. The origin of mires of this region is earlier than northeast China and Finland. This shows that the southern part of the Qinghai-Xizang Plateau and its adjacent areas may be the centre of the origin and distribution of temperate elements.  相似文献   

4.
I.I~crIOXNOwadays,theremotesensingtechniqueshavebeenappliedinmeteorology,oceanography,hydrologyandsomeotherscientificfields,andbecomeauSefulmethodformonitoricsavastregion.Monitoringwithsatelliteremotesensinghas~advantageSincollectingdatacontinuously,regularlyandrepeatedlyinalargearea,inparticularinavastwetlandwherethefieldinvestigationisverydifficult.Therefore,remotesensingwithsatellitedataisthemostsuitablemethodforthesurveyinthiskindofregion.Untilthecoddleofthe20thcentury,wetlandhassometim…  相似文献   

5.
I.INTRODUCTIONInthepaper,thewetlandinQinghaiLakedrainageareameansthemiremeadowintheregion.Itsformationanddevelopmentareclosel...  相似文献   

6.
Mire is the product of the Quaternary. It mostly formed, developed and declined after the postglacial age. Therefore the chemical element analysis, spore-pollen analysis, 14C dating, mire plant determination for mire sediment, and the study on hierarchy relation of mire sediment, can provide a lot of information for restoring paleogeography, paleoclimate and environmental change. So some people called mire sediment-peat as "database of environment".  相似文献   

7.
CARBON DYNAMICS OF WETLAND IN THE SANJIANG PLAIN   总被引:2,自引:0,他引:2  
1INTRODUCTIONWetlandsplayanimportant roleintheprocessofcar-bonstorage.Thetotalcarbonstoredindifferentkindsofwetlandsisabout15%-35%ofthetotalcarboninthegloballandsoils(POSTetal.,1982;GORHAM,1991).Inaddition,wetlandsaresignificantnaturalsources fortheatmospheric CH4 (MOORE,1994).It isestimatedthatabout110×1012gCH4 originates fromanaerobicdecompositioninthenaturalwetlands,CH4 emission fromthenaturalwetlandsis15%-30%oftheglobalCH4 emission andtheCH4 emission from thepeat land at hi…  相似文献   

8.
本文取材于《广西泥炭资源远景调查》成果。笔者认为广西泥炭产于第四系,其资源特点是: 分布广、规模小、类型多、质量好、易开发利用,有一定远景。按生成环境以地貌为主将广西泥炭矿床划分为5类8型,并分别以矿床实例论述其特征。着重指出岩溶洼地类型是广西泥炭资源的主要矿床类型。  相似文献   

9.
涌水是矿山安全生产的重要威胁之一,掌握涌水的水源是预防这类灾害的重要依据。基于多期次的水化学监测数据,提出了利用主成分分析(PCA)和残差分析来识别涌水的水源数量和水源类型。主成分分析能够充分提取高维数据的结构信息,消除变量冗余。残差分析利用主成分分析结果,提取不同的主成分个数重构离子浓度,得出重构离子浓度和原始离子浓度之间的残差,利用残差的结构性信息来判断可能的涌水水源数量和水源类型。结果表明:随保留主成分个数的增加,重构离子浓度的精度越高,离子残差的结构性得到消除且表现出随机性。在实例应用中,通过利用5个主成分重构离子浓度消除了所有主要离子残差结构性,保证了信息的最大程度提取,因此,确定研究矿山涌水水源数量为5个;同时,利用每个主成分对残差结构性的影响程度及离子相关性分析,确定了这5个水源类型为海水、第四系孔隙水、富钙基岩水、富镁基岩水和淡水。  相似文献   

10.
广西晚二叠世成煤模式划分为“两类三型”,即泥炭沼泽成煤模式和泥炭坪成煤模式两类,沼泽型、潮坪型和泥炭坪型等三型。文章阐述了这些成煤模式在吴家坪期和长兴期形成的特征,分布状况,以及代表煤层,指出潮坪型是广西晚二叠世时期最主要的成煤模式。  相似文献   

11.
1 INTODUCTIONWetlandcanperformenormousfunctionsinre sourceandenvironmentadjustment ,anditisoneoftheimportantecologicalenvironmentsthathumanbe ingsrelyon .Internationalcommunitieshavealreadypaid greatattentiontothewetlandresearch ,andsomeforeignershavedone…  相似文献   

12.
The grain-size distribution characteristics and grain-size parameters of sediment in two vertical sections of Daniugou peatland in the Changbai Mountains were systematically investigated. A comparative analysis of the sediment granularity using a discriminative function with Hongyuan peat, red clay, loess-paleosol, fluvial deposit as well as lacustrine deposit was also conducted. It turns out that the vertical section of Daniugou peat ash is primarily constituted by clay and silt particles, and the content of sand is relatively small. Grain-size frequency curves generally show a single-peak modality while a bimodal pattern is detected in the upper layer. The grain-size component and peak pattern of grain-size frequency curves also illustrate that peat ash materials were transported to the peatland by long-range aeolian dust during the deposition process, while there existed short-distance dust influence in peat deposition of the upper layer. Comparisons of grain-size parameters and the discriminative Y-value of Daniugou peat ash with those of typical aeolian sediments show close similarities, suggesting the possibility that atmospheric dust transport processes were involved in the accumulation of peat again. Moreover, the variations of grain-size distribution suggest the local environmental deterioration which is just the driving force of local dust elevation. Grain-size analysis of peatland sediment is demonstrated to be one effective method to extract information about regional and global environmental evolution, and more attention should be paid to current local ecological environment and to seeking a balance between economic development and environmental protection in Northeast China.  相似文献   

13.
针对余震震源机制解相对比较复杂、紊乱这一现象,借助ZMAP软件包的特点,提出在尽可能减少人为分区因素情况下,利用余震震源机制解反演计算震源区应力状态的具体思路。利用1994年美国北岭MW6.7地震的余震震源机制解,采用Michael提出的应力张量反演算法,对震后震源区的构造应力状态及其分布进行反演分析,探讨了地震后震源区应力状态的调整变化及其与地质构造的关系。结果表明:1)震后震源区最大主应力为近水平,方向为北北东向,北北东向的水平挤压是北岭震源区构造应力状态的一个明确特征;2)震后震源区深浅部的构造应力状态可能不完全一致,虽然深部和浅部的最大主应力方向均为北北东向,但震源区深部的应力类型为逆断型,震源区浅部的应力类型为走滑型,深部数据组的反演结果与区域构造应力场相一致。认为北岭地震后震源区深浅部构造应力状态的差异可能与震源区的地震构造和北岭主震的错动方式有关。北岭主震是一次逆冲型地震,地震发生后,在区域构造应力的作用下,震源区应力继续释放,隐伏的北岭断裂(可能包括其周围的小断层)继续逆冲运动,从而产生一些逆冲型的中小余震。深部构造应力状态没有发生明显的改变,但北岭断裂的逆冲运动有可能引起了震源区浅部应力状态的变化。  相似文献   

14.
The lake groups in the Songnen Plain are low plain lake groups, which are located in the temperate semihumid area in China. They are characterized by small area, shallow basin, thick density and various types. In the try for classifying comprehensively the lake groups, a classification system is developed based on three main factors, i.e. forming cause, water quantity and water quality. The most internal character can be concisely grasped through three principal indexes and three auxiliary indexes of three main factors. A sample of complicated changeable path is put forward for further analyzing and outlining these basic types, in the meantime, it’s linking up easily with the classification system of the single factor. According to the regional environment, the regional differences of the type composition and the principal types, the lake groups in the Songnen Plain can be divided into 6 sub-regions. Foundation item: Under the auspices of the National Natural Science Foundation of China(49671077). Biography: LU Jin-fu (1938–), male, professor. His research interest includes paleo-environment in the Quaternary.  相似文献   

15.
通过对四川红原日干乔泥炭剖面的孢粉研究,建立了4个孢粉组合带。自13.6ka以来,日干乔地区古气候经历了以下演化阶段:13.688~11.093ka以温湿气候为主,11.093~8.512ka气候较为干旱,2.74~5.39ka,8.512~5ka气候转暖,温和湿润,5ka至今,该地区气候环境最好,温暖湿润。孢粉组合特征显示该区在此阶段总体为温湿的草原环境,孢粉记录反应了红原县日干乔地区第四纪更新世经历了潮湿—干燥—潮湿的气候变化过程。  相似文献   

16.
A method has been developed for estimating the filtered narrow band surface albedo with Landsat/TM data. In this method, the surface albedo from filtered range of Landsat/TM is converted to the surface albedo with unfiltered spectral range. The atmospheric effects on each channel are systematically different, because of the different spectral behavior of atmospheric parameters. As a result, in this study, atmospheric correction has been done respectively in different parameters for visible and infrared channels. The surface albedos of the Kushiro Mire gotten with this method were compared with the observed data there. The results show that the satellite inferred albedos have a good agreement to the diurnal mean of ground observed albedos with 3% systematic error. There is a seasonal variation of albedo in high and low mires, the albedo decreased gradually from April to July and reached its minimum in July, further it rose gradually from August to October. It is also clear that there is a characteristic pattern of surface distribution according to the vegetation types of this area. The average surface albedos of each type of community are 0.164 for Sphagnum, 0.175 for Carex, 0.179 for Pragmites and 0.166 for Alnus. In the other words, the albedo in high mire (mainly covered by Sphagnum) is lower than that in low mire (mainly covered by Phragmites and Carex).  相似文献   

17.
1GENETICTYPESOFGROUNDICEINCHINAGroundiceisweldevelopedinthevicinityofthesouthernpermafrostlimitintheEurasiancontinent,inthen...  相似文献   

18.
The available data on tidal currents spanning periods greater than six months for the continental shelf of the East China Sea (26°30.052′N, 122°35.998′E) were analyzed using several methods. Tidal Current Harmonic Analysis results demonstrated that semi-diurnal tides dominated the current movement. The tidal currents of the principal diurnal and semidiurnal rotated clockwise with depth, with the deflection of the major semi-axes to the right in the upper layer and to the left in the lower layer. The vertical structures of two principal semi-diurnal constituents-M2 and S2-were similar, which indicates that the tidal currents are mainly barotropic in this area. The main features of the variation of the four principal tidal constituents with depth demonstrate that the currents in this region are influenced by the upper and lower boundary layers. Therefore, the tidal constituents of the shallow water are similar. Different vertical modes were calculated based on the Empirical Orthogonal Function (EOF) analysis of the Eastern and Northern components of the tidal currents, with a variance contribution for the zero-order model of at least 90%. The variance contribution of the baroclinic model is minimal, which further reveals a strong barotropic character for the tidal currents of this region.  相似文献   

19.
鄱阳湖地区土地覆盖空间分布格局与景观特征分析   总被引:1,自引:0,他引:1  
 鄱阳湖是我国第一大淡水湖,具有洪水调蓄、水源涵养等重要生态服务功能。掌握鄱阳湖地区土地覆盖的空间分布格局和规律,对于评价其环境保护和生态服务功能具有重要作用。本文利用环境卫星影像、2005年鄱阳湖地区土地覆盖数据,经遥感解译分析获取了鄱阳湖地区2010年土地覆盖现状数据及其空间分布格局图。研究表明:(1)采用2010年的环境星影像结合2005年土地覆盖数据,人工目视解译得到的2010年土地覆盖数据的精度为80.4%。(2)景观生态学、GIS及统计学的思想和方法可以为土地覆盖空间特征的定量分析提供技术支持。文中采用的斑块面积指数、斑块形状指数、不同土地覆盖类型的邻接指数,从不同角度反映了鄱阳湖地区土地覆盖的空间分布格局及景观特征。(3)景观指数能定量说明土地覆盖景观的形状、大小、数量和空间组合,能反映景观的生态环境特点、人类活动及社会经济状况。面积特征指数显示研究区农村聚落的离散度及破碎度最高;斑块形状指数反映出研究区水体形状趋于规则化,其受到人类的"围湖造田,围湖造地"及防洪工程建设的干扰。(4)不同土地覆盖类型的邻接指数能定量说明相邻类型在物质交换、结构与功能的相互影响及土地资源形成机制、演替过程等。水田与常绿阔叶林的邻接关系反映了人类"毁林开荒"活动对林地与水田演替关系的影响;水田与农村聚落的邻接关系,表明研究区耕地保护的重点是城镇及农村周边耕地的保护;城镇建设用地的邻接关系表明了人类生活所需的生活条件,为"移民建镇"工程提供了科学依据。分析认为:鄱阳湖地区是以耕地为主的农业区,并且有丰富的水资源及森林资源,但今后要重视农村土地的集约化利用、水资源保护、耕地资源保护和自然资源的合理开发利用。  相似文献   

20.
利用CYGNSS(cyclone global navigation satellite system)采集的GNSS卫星反射信号,提出一种基于星载GNSS-R的水体分布探测方法。首先对CYGNSS低轨卫星星座采集的GNSS反射信号进行处理,获取地表反射率数据;再按0.01°×0.01°的空间分辨率将研究区划分为格网,剔除异常值和无效值后,利用区域均值算法重新计算各格网的反射率,并利用格网样本方差和标准差作为衡量指标,采用随机游走图像分割算法进行水体分布探测;最后利用本文提出的方法分析刚果盆地的水体分布情况,并利用MODIS数据对结果进行评估。结果表明,星载GNSS-R具有较强的水体分布探测能力,进一步拓展了GNSS-R的应用场景。  相似文献   

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