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回顾了我国有关红色旅游、红色旅游共生及红色旅游绩效的相关研究并进行了综述。根据文献对相关概念进行了整理,根据研究成果的数量和内容对红色旅游相关研究进行了分析,提出了各发展阶段及各阶段内容特征。对旅游共生的研究内容进行了整理,对红色旅游研究进行了总结,得出了现阶段的发展和未来的展望。 相似文献
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蓝莓栽培土壤改良的机理及方法 总被引:2,自引:0,他引:2
基于从事5年蓝莓栽培经验,重点归纳了蓝莓土壤改良的方法,采用硫黄粉、草炭和针叶土等系列手段,调解了土壤pH值,不仅改良了土壤酸碱度,而且改善了土壤结构,增加了土壤通气性,为蓝莓丰产和改善品质风味奠定了基础。 相似文献
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文章简单回顾了我国工程经济学的发展史,陈述了我国工程经济学的现状并进行了分析。文章还讨论了我国工程经济学的发展方向,并提出了一些列的措施。 相似文献
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介绍了噪声污染的现状及相关概念,分析了噪声污染的一些特点,重点探讨了噪声污染的产生因素及其监测的方法,针对噪声污染的一些问题重点介绍了解决的办法,提出了一些进行噪声污染的监测对策。 相似文献
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2009年11月26至27日,国家林业局森林公安局在海南省举办了全国森林公安刑侦工作培训班。曹真巡视员发表了重要讲话,充分肯定了近两年来森林公安刑侦工作取得的成绩,分析了森林公安刑侦工作面临的形势,阐述了刑侦工作和刑侦队伍中存在的突出问题,进一步明确了森林公安刑侦工作的总体思路,对当前及今后一个时期的森林公安刑侦工作进行了全面部署。 相似文献
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In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length (SRL) of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nutrition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches. 相似文献
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IntroductionDuringthepasttwodecades,studieshaverevealedthatgrowingash(Fnainusmandshurica)andlarch(LarlksPP.)togetherinaproperwaycanincreasetheproduc-tivityQfthestandsI"'}'-'].Theyieldimprovementmechanismsattributetotwoaspects,i.e.,theabovegroundandundergr… 相似文献
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In natural ecosystems, nutrition available for plants shows great spatial heterogeneity. Much is known about plant root responses to the spatial heterogeneity of nutrition, but little is known about carbon usage in roots in nutrition-deficient patches and its effect on root longevity. In this study, split-room boxes were used for culture of Cercis chinensis seedlings, and the small rooms were supplied with different nutrition levels. The number of the first-order roots in the rooms with nutrition supply was significantly higher than that in the rooms with deficient nutrition. Specific root length (SRL) of the first-order roots in the rooms with deficient nutrition reached its peak at day 64 after nutrition treatment. There was no significant SRL differences between the two order roots during the experiment. Biomass of the first-order roots in the rooms without nutrition supply was significantly less than that of the first-order roots in the rooms with nutrition supply from day 64 to 96. The total biomass of the lateral roots in the rooms without nu-trition supply decreased from day 64 to 96. The activities of the enzymes in roots in the rooms without nutrition supply increased and the activities of alkaline invertases in roots in the two sides of split box did not change significantly. The activities of the enzymes in roots in the rooms without nutrition supply increased gradually. These results suggest that nutrition spatial heterogeneity induced the changes in root traits and plants actively controlled carbon usage in roots in nutrition-deficient patches by regulating the activities of invertases and sucrose synthases, resulting in the reduction in carbon usage in the roots in nutrition-deficient patches. 相似文献
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香榧细小卷蛾Lepteucosma torreyaeWu et Chen是危害香榧的主要害虫之一,在浙江省绍兴市1 a发生2代,以老熟幼虫在枯枝落叶中做茧越冬,翌年2月中旬化蛹,3月上旬成虫羽化并产卵,3月下旬第1代幼虫孵化,5月中旬化蛹,5月下旬成虫羽化,6月上旬产卵,6月中旬第2代幼虫孵化,11月上旬开始越冬。在第2代幼虫期,使用1.8%阿维菌素乳油、5%抑太保乳油、2%阿维苏云制剂、35%吡虫啉乳油及20%杀灭菊酯乳油等5种药剂10个浓度进行喷雾防治试验,施药9 d后,防治效果均达到100%。 相似文献
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Beech trees occur in significantly lower latitudes in continental East Asia than in Europe and North America. They are common deciduous trees in the deciduous forests of the temperate zone in Europe, the eastern part of North America and Japan. In continental East Asia, however, they are absent in the deciduous forests of the temperate zone, but occur in the forests of mountains in the moist subtropical zone, south of 34° Northern Latitude. The lower limits of their distribution in these mountains show a significantly different pattern from the usual distribution pattern of plants and vegetation: it declines as the latitude decreases. The altitudinal belts of beech species lie higher in the northern than in the southern parts of their distribution areas in China. Based on an analysis of the climate and the phenology of these deciduous trees, we show that the prevailing monsoon conditions are the main factor affecting the distribution of the Chinese beech species. 相似文献
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毛竹笋期激素含量及其分布规律的研究 总被引:7,自引:0,他引:7
吲哚乙酸(IAA)、赤霉酸(GA_3)、激动素(KT)和脱落酸(ABA)对毛竹生长和发育起着重要的调节和控制作用。本文应用高效液相谱仪对1~8年生毛竹笋期的竹叶、竹秆、竹鞭和当年正常生长的竹笋中IAA,GA_3、KT、ABA的含量及其分布规律进行了研究。研究结果表明:促进植物生长或细胞分裂的IAA、GA_3、和KT都是大年竹株含量高,小年竹株含量低。竹秆中IAA、的含量随年龄增大而下降,其回归式为 Y=6.548-0.778A r=0.914二者呈极显著的负相关。抑制植物生长的ABA在竹叶、竹秆中的含量则大年低小年高。四种内源激素以叶部含量最高,GA_3的含量分布规律是叶>鞭>秆,IAA、KT和ABA都是叶>秆>鞭。吲哚乙酸在竹叶中的含量呈明显的向基性增加,而脱落酸在竹叶、竹秆中的含量都呈明显的向基性减少。生长在同一鞭系上的各株竹子及其所紧连的竹鞭的代谢具有较大的相对独立性,因此用小年留养来改制大小年是可行的。竹笋中IAA、GA_3和KT都是顶部含量高、基部含量低。 相似文献
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Transverse swelling and its anisotropy in hinoki (Chamaecyparis obtusa) in several kinds of organic liquids and in water were investigated by means the replica method. There was more cross-sectional swelling of cell walls and cell wall thickness in earlywood than in latewood. Marked swelling toward cell lumens was observed in wood swollen in liquids that had higher swelling potentials than water. This suggests that the swelling of cell walls in these liquids is much greater than the external swelling. Feret's diameters of the cell lumens were reduced by swelling in all the observed cases except in the tangential direction of earlywood, suggesting that cell walls swell to a much less extent in width than in thickness. Deformation of cell shapes caused by the tensile force from the latewood were observed in the earlywood and in the transitional region from earlywood to latewood. When swollen in water, transverse swelling anisotropy caused only by the swelling in cell wall thickness were calculated to be 1.2 for the whole region over an annual ring and 1.4 for the earlywood. These values could not account for the external swelling anisotropy of 2.1. Considering obvious deformations of cell shapes in the earlywood and in the transitional region, we conclude that the interaction between earlywood and latewood is one of the prime factors contributing to the transverse swelling anisotropy of coniferous wood.Part of this report was presented at the 48th Annual Meeting of the Japan Wood Research Society, Nagoya, April 1998 相似文献
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全国杉木家系区域试验研究 总被引:1,自引:0,他引:1
湖南省林科院先后于 1984年春、 1989年春两次参加全国杉木家系区域试验。方差分析表明 :提供家系的种子园之间以及种子园内家系之间各主要数量因子存在显著差异。对样本观测值进行标准化变换主成分分析 ,求出遗传综合指数 ,再聚类分析评价 :湖南靖州、江西赣南、广西柳州、贵州东南、福建三明、广东曲江种子园提供的家系生长有明显优势。 相似文献
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杉木林林下植被的生长与发育,对林地地力的恢复具有重要意义.通过对定位试验地杉木人工林林下植被营养元素的分析,研究了杉木林间伐后林下植被营养元素含量与积累状况.结果表明;营养元素在植物不同器官中的含量是不同的;问伐区灌木层和草本层植物中大量元素和微量元素的积累量大于对照区,草本植物中营养元素积累的增长幅度不如灌木层植物大;间伐后林下死地被物中大多数营养元素含量和积累量均有所增加. 相似文献