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湿地保护是生态保护的重要课题,随着农田大量开发、项目建设不断增多,我国的湿地退化日趋严重,本文以三江平原湿地中具有代表性的八岔岛湿地保护工作为例,通过介绍八岔岛湿地保护工作现状及存在问题,结合实际工作情况提出相应的对策. 相似文献
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IntroductionReportedasthethirdpoleoftheearth(Zheng ,1996) ,theTibetregionisthemainbodyoftheQinghai TibetPlateau.Itcrosses 9°50′oflatitudefromsouthtonorthand2 0°30′oflongitudefromeasttowest,withavastareaof1 2millionkm2 andahighaverageelevationofover40 … 相似文献
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在靠近非洲马达加斯加岛的印度洋上,有一个美丽富饶的火山岛国——毛里求斯。早在16世纪,欧洲殖民者踏上该岛之前,岛上几乎到处是茂密的热带森林。如今,该岛上的原始森林已所剩无几,其中卡伐利亚树行将灭绝,几百年前,它们的踪迹遍布全岛。这种树木质坚硬细密,曾经是岛上大量出口的优质木材资源。可是今天,岛上残存的卡伐利亚树已寥寥无几。 1982年,美国威斯康星大学动物学教授斯坦雷·坦布尔,在岛上对卡伐利亚树作了几个月的深入研究。他惊奇地发现,尽管这种树年年开花结果,竟没有一颗种子发芽,而且以乎几百年来没有发过芽。他翻阅了历史记载,发现人们早就 相似文献
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世界权威杂志《生态学家》早在1987年发表的社论中就指出:各种物种,不管它们是细菌、草本植物、蠕虫、螨、蛙、蜥蜴,还是小型哺乳动物,就好比是将飞机联接为一个整体的铆钉。每个物种在维持生态系统中都起着重要作用。然而不幸,人类在被封为万物之灵以后变得日益骄纵,以至逐渐成为万物之霸,不断地挥起利斧滥砍滥伐,扣动扳机乱捕乱杀,撒开巨网大捞特捞,张开大口疯吃狂吃,贪婪霸道得简直不给其它生物以活路。于是,大地倾斜,生态失衡,许多物种相继绝迹,还有不少濒临灭绝。时值二十一世纪,人类的愚蠢行为还是未见收敛。 相似文献
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生物多样性与可持续发展的关系 总被引:14,自引:0,他引:14
生物多样性主要包括物种多样性,生态系统多样性和遗传多样性3个层次,本文围绕这3个层次,介绍了我国丰富我采的生物多样性,分析比较了生物多样性与可持续发展的相互作用及关系,探讨了我国为实施可持续发展而进行的生物多样性保护的一些措施和行动。 相似文献
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SU Jian-qiang YU Zhi-ming SONG Xiu-xian TIAN Yun HONG Hua-sheng ZHENG Tian-ling 《环境科学学报(英文版)》2005,17(6):1047-1050
The relationship between Alexandrium tamarense (Lebour) Balech, one of red-tide alga, and two strains of marine bacteria, Bacillius megaterium(S7 ) and B. halmapulus( S10 ) isolated from Xiamen Western Sea, was investigated by evaluating the growth state of A. tamarense and the variation of β-glucosidase activity in co-culture system. The results showed the growth and multiplication of the alga were related with the concentration, genus speciality of the bacteria, and growth stage of the alga itself. The growth of A. tamarense was obviously inhibited by S7 and S10 at high concentration. Either inhibition or promotion contributed much more clearly in earlier than in later stageof the growth of the alga. Furthermore, there was a roughly similar variation trend of the activity of extra-cellular enzyme, β- glucosidase, in the water of the separately co-cultured bacteria S7 and S10 with the alga. The β-glucosidase activity(β-GlcA) rapidly increased during the later algal growth accompanying the increase of the lysis of the alga cells. The obvious inhibition of A. tamarense by marine bacteria at high concentration and evident increase of β-GlcA in co-colture system would help us in better understanding the relationship between red-tide alga and bacteria, and also enlightened us the possible use of bacteria in the bio-control of red-tide. 相似文献