World’s largest macroalgal bloom caused by expansion of seaweed aquaculture in China   总被引：7，自引：0，他引：7  

Dongyan Liu  John K. Keesing  Ping Shi 《Marine pollution bulletin》2009,58(6):888-895

In late June 2008, just weeks before the opening of the Beijing Olympics, a massive green-tide occurred covering about 600 km² along the coast of Qingdao, host city for Olympic sailing regatta. Coastal eutrophication was quickly attributed with the blame by the international media and some scientists. However, we explored an alternative hypothesis that the cause of the green-tide was due to the rapid expansion of Porphyra yezoensis aquaculture along the coastline over 180 km away from Qingdao, and oceanographic conditions which favoured rapid growth of the bloom and contributed to transport of the bloom north into the Yellow Sea and then onshore northwest to Qingdao. At its peak offshore, the bloom covered 1200 km² and affected 40,000 km². This is the largest green-tide ever reported, the most extensive translocation of a green-tide and the first case of expansive seaweed aquaculture leading to a green-tide. Given similar oceanographic conditions to those that occurred in 2008, these green-tides may re-occur unless mitigation measures such as those proposed here are taken.  相似文献   

光-能谱集成技术系统及其地质应用     

刘德长  叶发旺  赵英俊 《地球信息科学学报》2006,8(4):15-18

本文阐述了遥感、物探、地质等多地学数据的综合应用技术和方法。作者从多源遥感数据在铀资源勘查中的应用特点出发,充分利用了铀矿地质的特色信息--航空放射性伽玛能谱(航放)信息,进行了信息融合,开发多光谱遥感、雷达遥感、高光谱遥感、航放四种信息融合的MR、MSR、HSR融合图像。在此基础上,将融合图像的解译成果与重力、磁力、地化、地质等其他地学信息进行复合分析,从而建立了具核工业特色的光-能谱集成技术系统。利用该系统在植被覆盖的花岗岩、火山岩和沉积盆地地区进行了地质填图和铀矿找矿应用,取得了很好的应用效果。  相似文献   

利用南山数据对PSR B0329+54的长时标轮廓稳定性的研究          下载免费PDF全文

陈建玲  王洪光  温志刚  王娜  吕成冰  闫文明 《天文学报》2021,62(4):36

利用新疆天文台25 m射电望远镜2003—2009年对PSR B0329+54长达453 h的观测数据,研究了这颗源在1540 MHz上正常模式和反常模式的轮廓稳定性时标.通过不同时间的积分脉冲轮廓与参考轮廓交叉相关系数分析,发现随积分时间的增加,两种模式的轮廓先是以较快的速度趋于稳定,在积分时间增加到约(4±1) min时,轮廓趋稳速率放缓,当积分时间达到(140±60) min (正常模式)或达到(65±15) min (反常模式)时,轮廓趋稳速度再次变快.相关系数的结果显示两种模式的轮廓在绝大多数积分时标上都不是完全随机的涨落.如果以发生轮廓趋稳速率从快到慢转变所需的积分时间作为轮廓稳定时标的判据,两种模式的稳定时标均大约为5 min.轮廓中不同成分强度比例的涨落随积分时间的变化关系各不相同,由此可以推断3个成分强度涨落性质有差异.造成轮廓趋稳行为在不同时标上有明显差异的原因有观测噪声和星际闪烁等.  相似文献   

天空地多源遥感数据的广义摄影测量学   总被引：1，自引：0，他引：1  

张永军  张祖勋  龚健雅 《测绘学报》2021,50(1):1-11

21世纪以来,随着云计算、大数据、物联网、机器学习等信息技术领域的飞速发展,人类已进入人工智能新时代.摄影测量学科也顺应新一轮科技革命的浪潮,快速发展为全新的广义摄影测量学,其载体平台、仪器设备、数据处理理论技术及应用领域都已发生显著变化,天空地一体化的多传感器多层次综合立体观测技术得到极大发展,全面进入综合智能摄影测...  相似文献   

论《太湖流域综合治理规划》的得失   总被引：4，自引：3，他引：1  

黄宣伟 《湖泊科学》2002,14(3):203-208

太湖流域综合治理规划工程建设即将全部完成,在1999年洪水时,防洪效益达92亿元,相当于工程全部投资。规划的成功之处在于有良好的防洪意识,平衡了地方效益;并有供水、通航和改善环境效益。然而,由于对某些工程参数论证不足,加上运用不能适应流域各地的过高要求,目前有进一步完善的必要。  相似文献   

中国内陆河流域绿洲发育度的综合评价   总被引：8，自引：0，他引：8  

李小玉  肖笃宁  何兴元  陈玮  角媛梅  宋冬梅  胡志斌 《地理学报》2006,61(8):855-864

人工绿洲是干旱区人类活动主要场所,绿洲管理和生态建设体现了人类活动的积极作用;而不适当的土地开发与经济活动又形成了对绿洲生存与可持续发展的过度压力与生态负荷。科学准确地对绿洲状态进行综合评价,已成了人们正确认识绿洲并对其进行生态建设和环境保护的重要前提。针对目前我国绿洲综合评价研究的指标单一、应用区域受限等缺陷和不足,提出了可普遍用于内陆河流域绿洲评价的指标体系--基于因子分析法的“绿洲发育度”,并以河西走廊的15个绿洲为研究对象进行了案例分析。结果表明：依据发育度综合评价值可将河西走廊绿洲划分为工业绿洲、较高开发程度的农业绿洲、中度开发的农业绿洲和衰退或较低开发程度的农业绿洲4个等级,与当地实际情况完全符合;同时,还可通过因子水平上的发育度指标对各个绿洲的优势和劣势进行准确的定量表达,为绿洲管理者和政策制定者提供简明、准确的科学依据。  相似文献   

大河流域综合发展的比较研究:以长江和罗讷河为例     

刘慧  蔡宗夏  Thierry Sanjuan 《地理学报(英文版)》2006,16(3):378-382

1 Research background The globalization in process challenges our traditional way of looking at territories. New regional entities are emerging at sub-continental level as it is the case in Western and Central Europe through the growing assertion of Europ…  相似文献   

微小型IMU/GPS组合定位定向系统研究     

何秀凤  徐勇  桑文刚 《武汉大学学报(信息科学版)》2005,30(11):991-994

介绍了一种低成本微小型惯性测量组件(inertialmeasurementunit,IMU)和双天线GPS构成的组合定位定向系统。为确保组合系统的实时性和滤波稳定性,提出了一种基于UD分解的快速卡尔曼滤波算法,给出了IMU/GPS组合系统的软硬件设计和实验结果。该组合系统应用于炮兵测地车,具有成本低、精度高等优点,能够提高炮兵测地保障的精度和速度。  相似文献   

A geographic approach of the global vulnerability in urban area: case of Manizales, Colombian Andes   总被引：2，自引：0，他引：2  

Anne-Catherine Chardon 《GeoJournal》1999,49(2):197-212

Manizales, intermediate city in the Andes of Colombia, is exposed to three major natural phenomena: frequent landslides, earthquakes and, to a lesser extent, floods, all sometimes causing catastrophic disasters. The city was established in 1849 on a high ridge between two rivers (interfluve). This narrow plateau has steep slopes that have been occupied since the early 1940's. Since then, a lack of sites approved for construction has not stopped urban expansion, which continues affecting unstable areas, even when geotechnic works have been realized in those areas. The people most frequently affected by hazards live in `sub-integrated' districts (shantytowns) situated in the more sloping lands. Nevertheless, recent disasters have occurred in the new developments where the middle classes live, showing the role of the urban growth in the creation of a growth of vulnerability and risk. The investigation consists of perfecting a method of analysis of the relationships between the urban process and the installation of such a situation. Using statistical tools (PCA and Bertin matrices), we estimated the global vulnerability of the city and represented it, at the scale of the neighbourhood level, in an integrated map. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Integrated Assessment of Mineral Resources and Environment in Mid-South of Shandong Province     

Wei Min Yao Yonghui Wang Xueping Faculty of Earth Resources  China University Geosciences  Wuhan 《中国地质大学学报(英文版)》2000,11(2)

CHARACTERISTICS OF MINERAL RESOURCES DISTRI-BUTIONIn the mid-south Shandong Province,the distribution ofmineral resources has zonality:(1 ) In the west-south part ofthe district(including Jining,Zaozhuang) ,are mainly en-riched energy mineral resources such as coal,gas and oil. (2 )The west-north part (including Zibo,Jinan,Taian and L ai-wu) is abundant in iron,coal,auxiliary materials. (3 ) Theeast-south part(including Weifang and L inyi) is rich in goldand nonmetallic m…  相似文献