关于建立长江流域生态安全体系的初步探讨   总被引：28，自引：0，他引：28  

吴豪  许刚  虞孝感 《地域研究与开发》2001,20(2):34-37

阐述了生态安全与生态安全体系的基本概念，提出了生态安全体系由生态安全组织管理系统，规划、决策与建设管理系统，政策与法律配套系统，信息管理系统，监测、预警、监督与评估系统和资金保证系统等组成；最后分析了长江流域生态环境问题现状，认为建立长江流域生态安体系非常紧迫，并勾画了这一体系的基本框架。  相似文献   

Changes and opportunities for integrated management of the Razim-Sinoe Lagoon System     

A. Vadineanu  S. Cristofor  Gh. Ignat  G. Romanca  C. Ciubuc  C. Florescu 《International Journal of Salt Lake Research》1997,6(2):135-144

The aim of this paper is to identify the general trend of changes and the basic requirements of the most important lagoon system of the Black Sea, on the basis of critical analysis of existing data. A more coherent set of data sampled after 1988 on the basis of some intensive and extensive study and research programmes, including the main trophic parameters and the most representative structural and functional features of this complex of ecotonal lakes, is comparatively analysed together with more fragmentary data previously existing. The structural and functional changes within this complex of lakes were analysed based on 31 most representative variables belonging to the main abiotic and biological compartments of the two main lakes, Razim and Sinoe: dissolved organic carbon, dissolved oxygen, trophic state index TSI, nutrient content and ratio, salinity, chlorophyll, phytoplankton, zooplankton, submerged macrophytes, zoobenthos, fish and birds. Two stages were distinguised in the main structural changes, including morphometric connections with the Danube River and the Black Sea and hydrochemistry and its effects on communities. These transitions were associated with two main driving forces, water desalinisation and rapid eutrophication, and with other two kinds of man-induced changes, local hydrotechnical buildings and long-distance variables operating over the entire Danube River watershed. The information support system for sustainable management of the Razim-Sinoe Lagoon Complex as a part of the Danube Delta Biosphere Reserve, integrating existing data from research programmes and an integrated monitoring system for new data is a final conclusion on further needs.  相似文献   

Remote Sensing Study of Gold Biogeochemical Effects in the Western Guangdong-Hainan Region1—A Case Study of the Hetai Gold Deposit     

Xu Ruisong 《《地质学报》英文版》1992,5(4):411-425

Abstract The vegetation has been poisoned by gold in the western Guangdong-Hainan region. The gold content of the leaves there is as high as 10-1961 times the abundance, the chlorophyll content is 10%-30% lower than that of the vegetation in metamorphic terrains and 10%-20% higher than that in granite terrains, and the carotenoid content is 10%-44% lower than the background value. The water content of leaves is 10% to 20% lower than the background value. The cells of leaves are deformed and broken. The leaf surface shows colour spots and becomes yellow or dark green. The spectral reflectance of the leaf surface is 5%-30% higher than the background value; the spectral shape has shifted 5-15 nm to the short wavelength. The gray scales of eanopy on images of Landsat TM and airborne imaging scanner (AIS) are 10%-100% higher than the background values. On Landsat TM and AIS false colour images, plants poisoned by gold display a yellow color, which disinguishes them from background plants. According to the spectral and image features of gold biogeochemical effects, the author has constructed a gold information system and expert prediction system, and thus two gold target areas and two gold prospect areas have been identified rapidly, economically and accurately in the western Guangdong-Hainan region which is extensively covered by vegetation.  相似文献   

我国山地农业气候资源优势及其合理利用     

张养才 《山地学报》1992,(1)

据我国农业气候调查和考察资料,分析不同山区光热水农业气候变量在垂直和水平方向的变化规律,提出山地农业气候资源具有立体性、多层性、多样性和多宜性的特征,建立山区农业气候资源垂直分层模式;据人力、物力、耕地、物价等社会条件和经济效益等因素约束,应用系统决策寻找山区不同层次最佳的作物布局和农作制,探讨农业合理布局的生态气候效益及开发山区资源优势的途径。  相似文献   

人类生态学辨析     

王发曾 《地球科学进展》1991,6(3):32-37

在生态学与其它地球科学相汇合的领域里,人类生态学是有很强生命力和发展潜势的新兴学科,代表了现代生态学的一个重要研究方向。本文辨析了人类生态学的历史演变、哲学思想和科学功能,提出了一个发展人类生态学的学科框架。  相似文献   

我国东北地区某些荒芜土地的景观生态建设   总被引：31，自引：0，他引：31  

景贵和 《地理学报》1991,46(1):8-15

我国东北地区荒芜土地的主要问题是:①土地自然生产力得不到充分发挥;②土地退化。本文根据景观生态学关于人与自然共同创造的思想及生物控制共生与自然界等级组织理论,主张在东北区域的沙地上建立林、草、田复合生态系统,在沙垅间长洼地上节节修筑沙坝,控制7—8月暴雨径流,再按不同生境种植水稻、芦苇及红麻,既适应环境,又提高生产力。  相似文献   

生态水文学:生态需水及其与流速因素的相互作用   总被引：5，自引：0，他引：5       下载免费PDF全文

刘昌明  门宝辉  赵长森 《水科学进展》1990,31(5):765-774

本文研究涉及生态水文学中生态需水问题的一般认知。探讨了生态系统动态变化与水流驱动力因素之间的关系，重点探讨水流驱动因素中的关键指标——流速，通过分析流速与生态系统相互作用，从生态水文学动力因素出发估算生态需水；基于生态流速和水力半径，提出考虑河道内生态需水与水力因素关系的生态水力半径法，充分利用水生生物信息（鱼类产卵洄游流速）与河道信息（水位、流速、糙率等）估算河道内生态需水；归纳生态水力半径法在生态需水计算中的初步应用：考虑污染物降解耦合水量水质的生态需水计算、考虑鱼类等生物对流速要求的生态需水计算、考虑河道冲淤平衡的输沙需水量计算等方面。本文提出的生态流速研究既包括生物生长发育适宜的流速，又包括流速大小变化所涉及的许多动力因素，旨在延伸与扩展生态水文学的内涵与应用。  相似文献   

人类活动对长江中游湿地生态系统的冲击   总被引：27，自引：1，他引：26  

蔡述明  周新宇 《地理科学》1996,16(2):129-136

长江中游平原湖区是中国湿地资源的重要组成部分,由于人类对湿地资源的开发利用,给平原湖区带来了“鱼米之乡的”美誉,成为中国重要的农业生产基地和经济发达地带,同时也对生态环境带来了一系列的冲击,湿地资源与环境亟待保护。  相似文献   

Human disturbance and trophic status changes in Crystal Lake, McHenry County, Illinois, USA   总被引：6，自引：0，他引：6  

Yangdong Pan  Richard Brugam 《Journal of Paleolimnology》1997,17(4):369-376

The paleolimnology (sediment chemistry, ²¹⁰Pb dating, pollen, and diatoms) of Crystal Lake, McHenry County, Illinois, USA was studied to investigate the impact of European settlement on lake trophic status. Pollen clearly indicates a vegetational shift from Quercus dominance to Ambrosia. ²¹⁰Pb dating suggests that the Ambrosia rise likely occurs around the 1840's, which is consistent with historical records on the European settlement in this area. Coincident with the vegetational shifts, several diatom species, Cyclotella meneghiniana, Fragilaria crotenensis, Asterionella formosa and Tabellaria fenestrata, all increase while C. comta decreases after the settlement. However, C. comta and Aulacoseira ambigua, two dominant species, remain abundant throughout the entire core. Their relative abundances at the surface sediments reach presettlement levels. It is hypothesized that Crystal Lake, a glacial lake rich in CaCO₃, may have been able to assimilate increases of phosphorus by coprecipitating phosphorus with CaCO₃. Such a 'buffering mechanism may be responsible for the lake's resistance to trophic changes or recovery following disturbance.  相似文献   

山地区域土地生态红线划定方法与实证研究——以重庆市涪陵区义和镇为例   总被引：4，自引：1，他引：3  

丁雨賝  冯长春  王利伟 《地理科学进展》2016,35(7):851-859

无序和不合理的土地利用是引发生态问题的重要因素。合理划定土地生态红线,可协调土地利用和生态环境的关系,促进土地资源的合理配置,保障区域生态安全。山地区域地势起伏较大,水系密布,土地利用破碎化,作为重要的水土保持和水源涵养区域,是进行生态恢复和重建的关键地区。本文以山地区域村镇为例,运用GIS平台,基于生态敏感性和生态服务价值,对土地生态进行综合评价,据此划定刚性和弹性的土地生态红线。生态敏感性评价的指标包括坡度、植被覆盖度、水体、土壤类型和降水侵蚀力等5个指标;生态服务价值评价的指标包括食物生产、原料生产、气体调节、气候调节、水文调节、土壤保持、维持养分循环、生物多样性和美学景观9个指标。义和镇的刚性生态红线内所包含的刚性生态保护区面积为43.90 km²,占义和镇总面积的44.34%。弹性生态红线包含的弹性生态保护区面积为29.18 km²,占义和镇总面积的29.47%。义和镇的生态红线范围主要包含东北部山地区域和南部水系丰富地区,该区域的生态敏感性较高,同时也有较高的生态服务价值,因此生态红线的划定对于生态修复和生态保护具有指引作用,为生态系统健康发展提供基础保障,并可为构建生态文明安全格局提供科学支持。  相似文献