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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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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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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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概述了紫茎泽兰的基本特征、起源和在我国分布的情况。综述了紫茎泽兰的研究现状,主要包括:从遗传特性上探讨了紫茎泽兰的生长优势;分析了紫茎泽兰的化学成分;研究了紫茎泽兰提取液的提取方式;根据紫茎泽兰提取液的化学性质做了杀虫活性的研究;最后指出了目前我国紫茎泽兰的开发利用存在的问题,并对我国对紫茎泽兰提取液的开发和合理利用提出了相关的建议。 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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金秋季节,巴马县所略乡的万亩有机油茶基地内,漫山遍野的油茶树上结满的果实压弯了树枝,绿油油的树叶间同时开满了五颜六色的花朵。果还未摘,花又开了,收获了秋天的喜悦又点燃了明年的希望,争妍斗艳的遍野油条,预示着明年又是一个丰收年。 相似文献
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徐曼莎 《绿色中国(综合版)》2011,(20):145-145
林权管理制度改革破解了制约集体林业发展的体制性障碍,林业发展活力明显增强。一是充分激发了农民造林、育林、护林的积极性,推动了生态建设和保护;二是解放和发展了林业生产力,发挥了林地资源的潜力,促进了农民的增收致富; 相似文献
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The indirect consequence of sika deer (Cervus nippon) grazing on the regeneration of Picea jezoensis var. hondoensis through its effect on the small rodent population was assessed by evaluating seed predation by mice inside and outside the
deer-proof fence on Mt Ohdaigahara, central Japan. Following construction of the deer-proof fence, Sasa nipponica, which covers the forest floor and is the main forage of deer, grew thicker inside the fence due to the absence of deer grazing
than outside of the fence. Higher numbers of two species of woodmice (Apodemus speciosus and A. argenteus) were found inside the fence, possibly because the thick S. nipponica growth provides better cover. Inside the fence, more seeds of P. jezoensis var. hondoensis were eaten by the mice than outside the fence. These results suggest that the mouse populations inside the fence increased
due to changes in S. nipponica cover, which subsequently increased seed predation by the mice, possibly preventing regeneration of P. jezoensis var. hondoensis. 相似文献
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经济林童期相对较长,前期经济收益较低,因此提高综合收益,降低前期管护成本是目前生产中急需解决的主要问题之一。为了降低经济林前期投入成本,提高经济收益,文中对枳和花椒两种植物篱笆与设施工程中常用的金属护栏网这3种防护措施的造价、维护费用、防护效果和经济收益进行了调查和比较分析。结果表明:植物篱笆中,花椒篱笆的经济收入最高,达到7.88元/m,而枳篱笆的防护效果较好,其经济收益较高,可达到7.00元/m;但是,植物篱笆的前期防护效果较差。而金属护栏网的造价和维护费用均最高,可达6.67元/m,但建置后即可起到防护作用,前期防护效果较好。文中综合分析认为,植物篱笆适合童期较长的经济林树种,而金属护栏网则适用于城镇近郊农业观光园、果树采摘园和经济价值不高的育苗基地,若将植物篱笆和金属护栏网结合起来使用,则可兼顾长短期效益,值得在生产中推广应用。 相似文献
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Habitat structure in Oku-Nikko, Japan, has been substantially modified by the overabundance of sika deer (Cervus nippon). A deer-proof fence (15.0 km and 900 ha) was constructed in 2001 to conserve vegetation. Although the understory inside the fence is dominated by Sasa nipponica (hereafter, Sasa), an important forage plant for deer, that outside the fence is dominated by Aster ageratoides leiophyllus (hereafter, Aster), an unpalatable plant to deer, and, partly, by bare floor. In this study, we examined the effects of deer on ground-dwelling insects and earthworms, the primary food resources of raccoon dogs (Nyctereutes procyonoides), and, thus, the bottom-up cascading effects of the herbivore on the omnivorous carnivore. Between July and September 2008, we examined the abundance of insects and earthworms by pitfall trapping and hand-sorting methods, respectively, both inside and outside the fence. The abundance of earthworms and insects (Scarabaeidae and Rhaphidophoridae) was higher on forest floors with Aster and/or bare floors outside the fence than on those with Sasa inside the fence. These results indicate that the increasing deer population in this area probably increased the number of these invertebrates outside the fence by modifying understory vegetation and/or depositing dung. Furthermore, the sighting rates of raccoon dogs obtained by spotlight counts were greater outside than inside the fence, suggesting that deer probably exert bottom-up cascading effects on raccoon dogs, at least during May to November, when the invertebrates are predominantly fed on by the omnivorous carnivore. 相似文献
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Hiromitsu Kisanuki Arisa Nakai Akiko Nadamoto Masako Wakino 《Journal of Forest Research》2009,14(6):342-348
We determined patterns of microsite suppression in dwarf bamboo Sasa nipponica when grazing deer were absent. This bamboo species is able to outcompete Hondo spruce (Picea jezoensis var. hondoensis) saplings under many environmental circumstances. We set up two 10 × 100 m plots inside a deer-proof fence within a subalpine
forest on Mt. Ohdaigahara, central Japan, and two similarly sized plots outside the fence. Within the plots, we surveyed microsites
where spruce saplings grew. We measured height and shoot elongation of all spruce saplings, and culm height and cover ratios
of dwarf bamboo growing around each spruce sapling. Spruce sapling density and average height were higher inside the deer-proof
fence than outside, as were bamboo height and cover. Thus, there was a negative effect of deer browsing on vegetation parameters
outside the fence and a suppression of the negative effect of bamboo on spruce sapling growth inside the fence. Spruce sapling
height was higher in tree-fall pits than in other microsites inside the fence, whereas both dwarf bamboo height and cover
were lower in pits and rocky sites than elsewhere. In soil and collar microsites, spruce sapling shoot growth was lower and
bamboo height and cover were higher than in pits and rocky sites. Inside the fence, dwarf bamboo cover was high, but pits
and rocks suppressed its growth, allowing spruce saplings to flourish. To restore heavily damaged spruce forests with advanced
saplings, it will be necessary to construct deer-proof fences and create and maintain microsites with pits and rocks. 相似文献
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Collisions against Fences by Woodland Grouse in Scotland 总被引:2,自引:0,他引:2
CATT D.C.; DUGAN D.; GREEN R.E.; MONCRIEFF R.; MOSS R.; PICOZZI N.; SUMMERS R.W.; TYLER G.A. 《Forestry》1994,67(2):105-118
A study was carried out in native pinewoods at Abernethy andGlen Tanar to investigate the effect of forest fences on capercaillieand black grouse. Collisions occurred at a rate of 0.25 and0.03 per km of fence per month for capercaillie and black grouserespectively. Male capercaillie had a higher proportion of severeand fatal collisions than females. Capercaillie tended to collidewith those sections of fence where there were moderately sizedpines (8.5 m) close (within 4.4 m) to the fence. Collision sitesclose to trees were most strongly associated with the heightof exposed trunk, suggesting that capercaillie fly under thecanopy and fail to see the fence. The annual mortality rateof radio-tagged capercaillie caused by collisions was 32 percent indicating that this was a major mortality factor. Collisionswere most frequent between September and November when capercailliewere dispersing. It is recommended that fences are removed whereand when they are unnecessary, or are made more visible, orare set back from old woodland. 相似文献
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《Forest Ecology and Management》1998,103(1):49-56
We investigated the browsing effect of sika deer (Cervus nippon Temminck) on the biomass and morphology of Sasa nipponica Makino et Shibata, a dwarf bamboo, in Mt. Ohdaigahara, central Japan. The investigation was performed through comparison of S. nipponica inside and outside a deer-proof fence. The S. nipponica outside the fence decreased in biomass (292.7 d.w.g./50×50 cm inside and 105.1 d.w.g. outside in August 1994), became miniaturized in culm height (49.1 cm inside and 15.6 cm outside), decreased in top leaf length (118.9 mm inside and 69.8 mm outside) and in culm diameter (2.0 mm inside and 1.2 mm outside) and densified in culm number (254/50×50 cm inside and 622 outside). After the destruction of the deer-proof fence, S. nipponica inside the fence underwent similar changes, that is, biomass decrease, miniaturization and densification in the next flush. 相似文献
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Live fencing, an age old and traditional agroforestry practice, remains relatively less understood and least documented at least in India. Exploratory surveys conducted in the northern part of the Eastern ghat region of India covering five districts of three states (Andhra Pradesh, Orissa and Chhatisgarh), indicated that traditional farmers have vast knowledge about their live fencing practices and the species used. Two groups of species were observed on the fence. The first group of thirty three species were used primarily for protection and denoted as fence species. Together, they also provide 22 other products and services. The second group of species maintained on the fences for production purposes include five fruit trees, fifteen other trees and two climbers. The fencing practices were classified into two groups (single species and multiple species live fence systems) depending on the species used and into three groups (live fencing around field crops, around backyards or homesteads and around orchards/plantations) depending on the landscapes being protected. Only 20% of fences were dominated by single species; the rest were under multiple species.Ninety percent of house backyards were fenced, whereas only one percent of crop fields and seventy percent orchards were fenced. Some promising fence species of this region are Acacia caesia, A concinna, A. nilotica, Agave sisalana, Annona squamosa, Borassus flabellifer, Carissa carandus, Lawsonia inermis and Murraya koenigii 相似文献
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