基于高空间分辨率的红树林卫星遥感监测技术进展   总被引：1，自引：0，他引：1  

苏岫  赵冬至  黄凤荣  吴涛  王祥 《热带海洋学报》2011,(3)

卫星遥感技术是红树林生态系统监测的重要手段。文章系统地总结了红树林的光谱特征,给出了目前应用于红树林生态监测的高空间分辨率卫星包括IRS-P6、SPOT-5、IKONOS、OrbView-3、QuickBird的主要技术参数以及它们在红树林遥感监测中的应用程度,叙述了目视解译法、波段组合法、图像分类法、专家分类法、模糊分类法和面向对象分类法等遥感监测技术方法在红树林的生态参数包括类外区分和类内区分、生物量和健康状况等的遥感提取的应用和精度对比情况。另外,对应用高分辨率卫星遥感资料监测红树林的技术发展趋势进行了讨论。  相似文献   

珠江口红树林湿地演变的遥感分析   总被引：29，自引：0，他引：29  

黎夏  刘凯  王树功 《地理学报》2006,61(1):26-34

广东拥有全国面积最大的红树林湿地。但近年来经济的快速发展使得该湿地系统发生了很大的变化。利用多时相的遥感图像和专家系统方法对珠江口红树林湿地的时空变化进行了分析。结合雷达遥感图像,对红树林群落分类及生物量估算进行了研究,改善了单独使用光学遥感的不足。获得了试验区红树林的变化趋势、类型分布及生物量等情况,为红树林湿地的生态保护提供了重要信息和新的监测手段。  相似文献   

海啸波作用下泥沙运动——Ⅴ.红树林影响下的岸滩变化          下载免费PDF全文

陈杰  管喆  蒋昌波 《水科学进展》2016,27(2):206-213

近年来频发的海啸灾害造成巨大损失,而红树林具有很好的减小海啸灾害的作用。实验采用PVC圆管来概化模拟红树林,以无黏性沙堆砌而成1/10~1/20组合坡概化岸滩,选取孤立波模拟海啸波。实验结果表明,红树林的存在对岸滩剖面变化产生了较大影响,适当增加植物分布密度,并优化植物的分布方式,可有效减小海啸波对岸滩的冲刷危害。在本次实验条件下,得到了岸滩冲刷坑尺度、淤积沙坝尺度、最大冲刷深度、最大淤积高度与红树林的分布方式和密度、海啸波波高、泥沙比重和岸滩坡度之间的关系式,揭示了沙质岸滩剖面变化与红树林、海啸波水动力特性、泥沙颗粒、岸滩坡度之间的内在联系,为减小海啸灾害提供科学依据。  相似文献   

Estimation of daily average net radiation and its variation over West Bengal,India using MODIS products     

Dibyendu Dutta  Prachi Goel  Manisha Singh  Vinay Kumar Dadhwal  Rodda Suraj Reddy 《国际地球制图》2017,32(3):286-297

A simple and exclusively satellite-based instantaneous net radiation (INR) and its components have been estimated and it is based on the method proposed. The method has been used to check its suitability over West Bengal, India on clear sky days which is eliminating the need for ground-based observations. The method explicitly recognizes the need for spatially varied input parameters to estimate net radiation using remote sensing information and provides a distributed daily average net radiation map with finer spatial resolution. The satellite-derived radiative flux components were compared with the Eddy Flux Tower measurements located at Bonnie camp within mangrove forest. The bias, root-mean square error and R² between modelled and measured INR are 52.07, 49.5 W m^?2 and 0.74, respectively which are within the acceptable limit. The errors in the downward short wave and long wave as well as upward short-wave and long-wave radiative flux are 13.78, 3.54, 12.41 and 3.54%, respectively. Further, variations of all the radiative flux components were analysed over different eco-systems.  相似文献   

大亚湾核电站邻近埔渔洲红树林区软体动物生态研究   总被引：1，自引：0，他引：1  

李荣冠  江锦祥 《海洋科学集刊》1997,(39):115-122

本文研究了大亚湾埔渔洲红树林区软体动物种类组成,数量分布和群落结构特点,报道软体动物已鉴定有35种,主要由樱蛤科、帘蛤科和汇螺科组成;按种类性质,大多属于广温广盐广布种。平均生物量为51.15g/㎡,平均栖息密度为58个/㎡,群落可划分高、中、低3个分布带,同时简要地分析了生物群落与环境因子的关系。  相似文献   

红树林海洋细菌的分离鉴定及其活性物质初步分析   总被引：5，自引：1，他引：5  

梁静娟  庞宗文  詹萍 《热带海洋学报》2006,25(6):47-51

从广西北部湾红树林海洋淤泥中分离筛选到270株海洋细菌,用喉癌细胞Hep-2的细胞毒作用为筛选模型,用SRB法检测这270株海洋细菌的抑制肿瘤细胞生长活性,其中13株呈阳性反应。依据形态和生理生化反应特征及16SrRNA基因序列分析,确定其中一株为短小芽孢杆菌Bacillus pumilusPLM4。取该菌株液体培养上清液,检测对人喉癌细胞Hep-2的生长抑制率为63.9%,经过凝胶过滤层析分析获得2个活性峰,其中活性高的峰估计平均分子量为116kd。采用经典显色反应法初步判断该活性物质为多糖。  相似文献   

红树植物中铝的示波极谱滴定     

杨孙楷  苏循荣 《台湾海峡》1992,11(4):359-362

锌在示波极谱图上具有敏锐的切口,在pH为2～3的HCl-NaCl介质中,可用EDTA直接滴定铝。当滴加EDTA至切口消失时,即达到滴定终点。对红树植物体中铝的分析结果表明:此方法具有直观、操作简便、分析快速的优点,回收率相对误差在10%左右。几种红树体的不同部分铝的质量分数(干重计)分别是:叶为(6.69～29.9)×10~(-3),树干为(1.91～26.8)×10~(-3),常年生树枝为(5.54～29.8)×10~(-3).  相似文献   

Salinity tolerance of northern Brazilian mangrove crab larvae, Ucides cordatus (Ocypodidae): Necessity for larval export?     

Karen Diele  Darlan J.B. Simith   《Estuarine, Coastal and Shelf Science》2006,68(3-4):600

The life cycle of the semiterrestrial mangrove crab Ucides cordatus includes pelagic larvae that are released into estuarine waters during the wet season and who may thus encounter potentially stressful low and variable salinity conditions. The effect of salinity on the survival of the zoea larvae, the number of zoeal stages and the duration of development from hatching to megalopa was experimentally studied by rearing larvae from the Caeté estuary, Northern Brazil, in seven salinity treatments (0, 5, 10, 15, 20, 25, and 30). For a better interpretation of the laboratory results, estuarine salinities were measured over five consecutive years during the species' reproductive season. The survival of the zoea larvae varied significantly with salinity, while the number of stages and the duration of their development remained constant. Development to megalopa took 20.77 ± 1.57 days and comprised five zoeal stages with ZI and ZII being euryhaline and later stages stenohaline. The newly hatched larvae stayed alive for up to 6 days in freshwater (average 4.32 ± 0.82 days), but did not moult to the second zoeal stage. ZII larvae first occurred from salinity 5 onwards and later zoeal stages at all tested salinities ≥10. However, the larvae only survived to megalopa at salinities ≥15, with highest numbers at salinity 30 (72%) and lowest at 15 (16%). Lethal salinities ≤10 occurred frequently in the estuary during the reproductive season. This suggests a need for larval export to offshore and thus more saline waters to allow for significant larval survival and maintenance of viable populations of this commercially important species. A regional rather than local approach for management is suggested due to the likelihood of long distance larval dispersal by offshore currents.  相似文献   

On the Occurrence of Marine Fungi in the Diet of Littorina angulifera and Observations on the Behavior of the Periwinkle*     

J. Kohlmeyer  B. Bebout 《Marine Ecology》1986,7(4):333-343

Abstract. The feeding and resting patterns of Littorina angulifera, the southern periwinkle, were observed in mangrove habitats of Belize (Central America). The snails feed predominantly on the surface of prop roots of Rhizophora mangle in a narrow zone at and above the mean high water mark. This area contains large numbers of hyphae and chlamydospores of an unidentified marine fungus (Deuteromycetes) and filaments of a chlorophyte (Chlorochytrium sp.). Both organisms are ingested by snails whose digestive tracts and fecal pellets contain ground-up cork cells, tricho-sclereids, tracheids, calcium oxalate crystals, fungal hyphae and chlamydospores, as well as undigested cyanobacteria. Most fungal particles pass through the gut unchanged. During dry periods, L. angulifera is in a dormant state, usually attached with dried mucus to leaves high in the tree, causing necrotic, crescent-shaped marks. The leaf tissue under the area of shell attachment becomes meristematic, separating dead tissues from healthy mesophyll. The snails detach during rainfall and move downward to the feeding sites on the prop roots.  相似文献   

九龙江口及邻近港湾红树林区沉积物中多环芳烃污染现状及评价   总被引：3，自引：0，他引：3  

陆志强  郑文教  马丽 《台湾海峡》2007,26(3):321-326

本文应用沉积物质量评价基准法对九龙江口及邻近港湾红树林区表层沉积物中多环芳烃的污染现状进行了生态风险评价,并定量分析了多环芳烃的相对污染强度.研究结果表明:各测站区多环芳烃相对污染系数均小于1,范围为0.022~0.620,污染程度尚属较低,引起生物毒性效应的几率相对较小.低分子量多环芳烃芴、萘和二氢苊占总相对污染系数比例较高(平均分别为18.1%、16.7%和15.3%),因而具有相对较高的潜在生态危害风险.  相似文献