Total N,total P and organic matters content in floodplain soils of Xianghai Nature Reserve

Soil sediment samples of 10 layers with a spacing of 10 cm each were collected in different floodplain zones adjacent to Huolin River in the Xianghai Nature Reserve, and contents of total N, total P and organic matters were analyzed. The results showed that contents of total N, total P and organic matters were generally decreasing with the increase of distance from sample locations to the river channel, and contents of the three items were generally higher in the upper soil layer than that in the lower soil layer. The content variations displayed how flooding functions influenced nutrient matter content variations in floodplain soils since the flood inundation frequencies of the sample locations varied. The correlation analysis displayed that there were remarkable relativities between total N, total P and organic matters within definite spatial distance from the Huolin River channel.     

Wetland vegetation biomass estimation and mapping from Landsat ETM data:a case study of Poyang Lake

Poyang Lake is the largest freshwater lake in China. This paper conducted a digital and rapid investigation of the lake’s wetland vegetation biomass using Landsat ETM data acquired on April 16, 2000. First, utilizing the false color composite derived from the ETM data as one of the main references, the authors designed a reasonable sampling route for field measurement of the biomass, and carried it out on April 18-28, 2000. Then after both the sampling data and the ETM data were geometrically corrected to an equal-area projection of Albers, linear relationships among the sampling data and some transformed data derived from the ETM data and the ETM 4 were calculated. The results show that the sampling data is best relative to the band 4 data with a high correlation coefficient of 0.86, followed by the DVI and NDVI data with 0.83 and 0.80 respectively. Therefore, a linear regression model, which was based on the field data and band 4 data, was used to estimate the total biomass of entire Poyang Lake, and then the map of the biomass distribution was compiled.     

川西北高原若尔盖草地沙化及湿地萎缩动态遥感监测

应用卫星遥感资料(MSS、TM及spot)对川西北高原若尔盖草地沙化及湿地萎缩的动态监测发现，自1966年至2000年的34年间，草地沙化面积增加307．7％，达到36760．9hm^2，占区域总面积的7．25％，平均每年扩大草地沙化面积816．0hm^2，年均递增率达4．22％。到2000年止，区域内有沙地5083．9hm^2，沙化草地31677．0hm^2。自1985～2000年的15a间，区内17个湖泊面积缩小842．0hm^2，减幅达38．9％，平均每年减少56．1hm^2，年均递减速度达3．34％，该区目前其余11个湖泊总面积仅为1323．1hm^2，只有15年前的61．1％。     

盐碱化湿地稻-鱼复合生态系统微生物特征

为揭示盐碱化湿地稻-鱼复合生态系统微生物群落结构特征,1994-1995年,对松嫩平原苏打盐碱化湿地稻-鱼复合生态系统水体与土壤中的微生物数量及种群组成进行了初步研究。结果表明,稻-鱼湿地水体中异养细菌数量显著高于稻田湿地(P<0.05),季节变化特点为秋季>夏季>春季。异养细菌的数量分布与鱼产量有显著相关关系(r=0.879)。稻-鱼湿地系统的土壤微生物数量明显高于稻田湿地(P<0.01)。稻-鱼湿地和稻田湿地分别检测出10个和11个属的异养细菌。稻-鱼湿地系统1个生长期细菌的平均生物量为0.973g/m3,生产量为307.5 kg/hm2,所提供的鱼产力为7.0 kg/hm2。     

松嫩平原内陆盐碱湿地的类型特征及分布规律

内陆盐碱湿地是湿地的重要组成部分,其类型、特征及分布规律的研究十分薄弱。松嫩平原是世界上内陆盐碱湿地发育的典型地区之一。本文参考国内外湿地分类标准,结合松嫩平原的特点,建立了内陆盐碱湿地的分类体系,将该区的盐碱湿地划分为2个湿地类,6个湿地型,13个湿地亚型,描述了各类型的主要特征,并阐述了松嫩平原内陆盐碱湿地的分布规律。这对我国的湿地分类系统是一个重要的补充,对进一步实施内陆盐碱湿地的保护、恢复和重建,促进松嫩平原社会经济和环境的可持续发展都具有重要意义。     

多氯联苯湿地生物降解规律预测及污染风险分析

建立了一个数学模型来预测多氯联苯湿地生物降解过程。该模型全面考虑了多氯联苯湿地生物降解的各子过程,包括:吸附/解吸、土壤屏蔽、扩散和生物降解,利用模型,预测了多氯联苯湿地生物降解的规律性及处理时间、处理终点;利用Monte-Carlo法,进行了多氯联苯湿地生物降解污染风险分析,结果表明,在采用基地现有处理方式的情况下,经过8年处理,土壤中4-Cl-PCBs不低于69.4%被降解的可能性为75%,此时土壤中能够继续污染外部环境的4-Cl-PCBs部分不超过10.9%的可能性为75%;土壤中4-Cl-PCBs全部生物降解完毕所需处理时间不超过16.20年的可能性为75%,最后被土壤不可逆屏蔽的残余物不超过20.9%的可能性为75%。     

黑龙江省湿地资源遥感信息解译分析

按黑龙江省湿地分类标准，应用资源卫星遥感技术，建立湿地资源解译标准，判别分析全省湿地资源现状与区域分布。     

The transition from passive to active margin tectonics: a case study from the zone of Samedan (eastern Switzerland)

The Zone of Samedan is part of a fossil, early Mesozoic rift system originally situated in the distal, Lower Austro-Alpine domain of the Adriatic passive continental margin. An early Mesozoic configuration of asymmetrical rift basins bounded by relative structural highs compartmentalized Late Cretaceous active margin tectonics; Jurassic half-grabens were folded into arcuate synclines, whereas relative structural highs engendered thin, imbricated thrust sheets. West-directed thrusting and folding initiated at the surface and continued to depths favoring mylonitization under lower greenschist-facies conditions. At this time Liguria-Piemontese ophiolites were accreted to Lower Austro-Alpine units directly underlying the Zone of Samedan. Late Cretaceous orogenic collapse of the Adriatic active margin involved the reactivation of west-directed thrusts as low-angle, top-to-the-east, normal faults. These faults accommodated extensional uplift of Liguria-Piemontese ophiolites and Lower Austro-Alpine units beneath and within the Zone of Samedan. During Paleogene collision, some Late Cretaceous faults in the Zone of Samedan were reactivated under lower anchizonal conditions as north-directed thrusts. The latter stages of this early Tertiary thickening were transitional to brittle, high-angle normal faulting associated with top-to-the-east extension and spreading above the warm, uplifting Lepontine dome.     

Effects and removal of systematic errors in crosshole georadar attenuation tomography

We have developed an algorithm that allows crosshole georadar amplitude data contaminated with systematic errors to be tomographically inverted. The effects of the errors, which may due to variable antenna-borehole coupling, the groundwater table, and 3-D heterogeneities in the vicinity of one or more boreholes, are included in a series of transmitter and receiver amplitude-correction factors. Tests with synthetic georadar sections demonstrate that the new approach is capable of producing reliable attenuation information, even when large systematic errors are present in the amplitude data. Standard inversions of crosshole georadar data acquired within a highly complex alpine rock glacier yield distorted tomograms. In contrast the new approach results in geologically useful images.     

天津市湿地环境变迁及成因分析

应用3S技术对天津湿地环境进行调查，结合地面采集的历史和现状数据，全面分析了天津湿地环境变迁的自然和人为因素。近一个世纪以来，天津湿地持续减少，天然湿地丧失殆尽，人为因素影响是天津湿地环境变迁的主要原因。城市拓展、经济开发对湿地的占用以及水环境污染是目前湿地面临的主要威胁。保护天津湿地要从搞好城市土地利用规划、调整产业结构、控制水污染、加强湿地保护区管理、尽快制定湿地保护法等方面入手。、