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东海区经济虾类资源管理对策探讨 被引量:3
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作者 程家骅 戴国梁 +1 位作者 凌建忠 刘敏 《中国水产》 北大核心 2003年第1期74-75,68,共3页
20世纪80年代以来,随着东海区主要经济鱼类资源的严重衰退,捕食虾类的鱼类明显减少,生物之间的相互竞争趋于缓和,客观上形成了现有的生境有利于虾类的繁衍生长,虾类资源数量呈现出逐年增长趋势.但是出于对渔获产量与利润的追求,人们对... 20世纪80年代以来,随着东海区主要经济鱼类资源的严重衰退,捕食虾类的鱼类明显减少,生物之间的相互竞争趋于缓和,客观上形成了现有的生境有利于虾类的繁衍生长,虾类资源数量呈现出逐年增长趋势.但是出于对渔获产量与利润的追求,人们对虾蟹类资源利用的强度也在逐年增加,特别是自1995年东海区实施伏季休渔制度后,导致"伏休"期间转产拖虾生产的渔船剧增,拖虾作业捕捞力量近趋于失控,加之90年代脉冲惊虾仪的普遍使用,造成了虾类资源的过度利用,虾类资源密度不断下降.针对这一严重态势,本文现根据近年来渔业资源与虾类资源利用的调查结果,通过对主要经济虾类的繁殖期与分布特征等的分析,仅就东海区经济虾类资源的保护与合理利用提出如下浅见供决策部门参考. 展开更多
关键词 东海区 经济资源 资源管理 繁殖期 分布区域 拖虾渔业
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贵州植物资源概况探讨 被引量:2
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作者 舒瀚 罗波 《绿色科技》 2019年第3期135-137,共3页
指出了贵州植物资源丰富,生物多样性在全国居前列。介绍了贵州保护类和经济类植物资源概况,探讨了保护类资源如国家重点保护植物、珍稀濒危植物、省级保护植物、古大树、古茶树和种质资源的现状,经济类资源如药用、观赏、经果林、森林... 指出了贵州植物资源丰富,生物多样性在全国居前列。介绍了贵州保护类和经济类植物资源概况,探讨了保护类资源如国家重点保护植物、珍稀濒危植物、省级保护植物、古大树、古茶树和种质资源的现状,经济类资源如药用、观赏、经果林、森林蔬菜、用材、油料等的现状,对其今后的发展提出了对策与建议。 展开更多
关键词 植物资源 保护资源 经济类资源 贵州
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Characterization of 124 Flue-cured Tobacco Germplasm Resources
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作者 许美玲 肖炳光 +1 位作者 焦芳婵 吴兴富 《Agricultural Science & Technology》 CAS 2013年第2期286-294,383,共10页
[Objective] This study aimed to characterize 124 flue-cured tobacco germplasm resources, and to provide reference for making the best use of the existing flue-cured tobacco germplasm resources. [Method] A total of 124... [Objective] This study aimed to characterize 124 flue-cured tobacco germplasm resources, and to provide reference for making the best use of the existing flue-cured tobacco germplasm resources. [Method] A total of 124 flue-cured tobacco germplasm resources were studied via field experiment and statistic analysis to investigate characteristics of their growth period, morphologic characters, main agronomic traits, and economic characters. [Result] There were significant differences among the 124 flue-cured tobacco germplasm resources in growth period, morphologic characters, main agronomic traits, and economic characters. The coefficients of variation (CV) varied in a range of 7.9%-22.5%. Among them, CV of bud stage was higher, and that of corolla length was lower. Many germplasm resources were attacked seriously by black shank disease at the end of field experiment, including those with disease index higher than 90, like Kutsaga 110, TI706, Ky 151, KM10, Longshe, Chaoxian Kangchi, Kutsaga 51E, Yongding No.1, and those with disease index among 75-90 such as Liaoyan No. 8, Lingnong No.2, Shandong Duoye, 581, Cunjingyan, KRK26, and Special 400. The tobacco root knot nematode invasion was light in some germplasm or never happened in other germplasm resources. TMV happened sporadically. CV 87, Yunyan 99, Yunyan 85, K326, Yunyan 87, Zhubuo No.1, T64 and T66 produced higher yield, production value, proportion of good leaves and sold at a higher price. Finally, we screened out the germpalsm resources with good comprehensive economic values and high disease resistance such as CV 87, Yunyan 99, Yunyan 85, K326, Yunyan 87, Zhubuo No.1, T64, T66, Honghuadajinyan, G-28, Taiyan No. 8, 77089-12, Yunyan 97, K346, V2, K149, NC567, NC297, Yunyan 201, Yunyan 203, KRK22. [Conclusion] This study provides reference for making better use of tobacco germplasm resources, and breeding new varieties. 展开更多
关键词 Flue-cured tobacco Germplasm resources Cluster analysis Economic characters Agronomical characters
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The depletion of coastal environmental resources by human activities and its monetary evaluation
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作者 Wang Xuan Chen Weiqi 《Ecological Economy》 2007年第1期67-76,共10页
The marine environment provides rich and varied resources and services or functions for human’s produc-tion and life. Many countries have competitively exploited and utilized sea and ocean to develop marine economy f... The marine environment provides rich and varied resources and services or functions for human’s produc-tion and life. Many countries have competitively exploited and utilized sea and ocean to develop marine economy for someyears. The over-exploitation of marine environment and the overuse of marine resources have led to resource degradation,environmental pollution and ecosystem destruction. Considering the depletion of coastal environmental resources dur-ing planning, governing and decision-making is an important measure to promote the harmonious and sustainabledevelopment of coastal environmental resources and social economy, the main precondition of which is that the depletionof coastal environmental resources by human activities has been monetarily evaluated. Firstly, this paper summarizesrelevant references in this field and analyzes different sorts of depletion of coastal environmental resources caused byhuman activities and the necessity and importance of the monetary evaluation. Finally, this paper extensively discussesthe corresponding evaluation models of the depletion of marine mineral resources, marine organism resources, mari-time transport resources, intertidal zones and shallow seas, and marine environmental functions and services includingenvironmental capacity, gas regulation, disturbance prevention, recreation and biodiversity. 展开更多
关键词 Coastal environmental resources Depletion Monetary evaluation Human activities
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