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福建石牛山国家森林公园的生态文化与开发森林旅游的思考 总被引：3，自引：0，他引：3
阐述闽南石牛山国家森林公园生态文化的主要内容，分析发展森林生态游具备的有利因素、不利因素与不足，思考石牛山森林生态游的开发对策与建议。 相似文献
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从生态学角度谈干旱半干旱地区造林的关键技术措施 总被引：1，自引：0，他引：1
魏洁 《内蒙古林业调查设计》1995,(2):4-8
自然界形成的森林是林木长期适应自然环境的结果。造林虽不同于自然界森林的形成，它是通过人工手段，在无林地上建立森林植被的过程，但在这个过程中要想保证苗木的成活和正常生长，就必须遵循生态法则，根据生态因素与苗木的关系，因地制宜地采取各种措施，做到科学利用环境的有利因素，改造和控制不利因素，为苗木创造一个适生的环境，达到苗木与环境的统一。在干旱半干旱地区造林生态环境中有许多诸如日照充足，雨热同期等对苗木生长有利的因素，但总的环境质量较差，有很多不利因素，其中最大的限制因素是气候干旱和土壤严重缺水。那么怎样才能充分利用这些有利因素，克服不利因素达到苗木与环境的统一呢？笔者认为从生态学角度应关键抓好以下几个方面的技术措施。 相似文献
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我国作为果树栽培的樱桃有中国樱桃、欧洲樱桃。欧洲樱桃因其果个大,又称大樱桃。大樱桃属于蔷薇科樱桃属落叶果树。大樱桃成熟期早,有早春第一果的美誉,果实营养丰富,含铁量高,促进血红蛋白再生,对贫血患者有一定的补益作用。果实性温、味甜,有调中益脾、调气活血、平肝祛热之 相似文献
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通过对介休市核桃经济林产业的调查,分析了介休市发展核桃经济林产业面临的有利因素和不利因素,提出了今后介休市发展核桃经济林产业的建议。 相似文献
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利用黑龙江省夏季林火的火场资料、温度、降水和NCEP再分析资料,在分析黑龙江省夏季林火气候背景与林火发生期和发生前期气象条件的基础上,研究黑龙江省夏季林火多发年大气环流特征,结果表明：进入21世纪以来,黑龙江省夏季林火呈明显增多的趋势;夏季林火发生前期（春季）的气候条件并不是夏季林火是否发生的决定性因素;夏季持续高温少雨天气,为林火的发生提供了有利的气象条件,林火发生期（夏季）的旱涝状况是决定林火是否发生的关键因子;林火多发年高低空大气环流均存在异常变化。高低空大气环流的配置．均不利于黑龙江省夏季降水的出现,从而为夏季林火的发生提供了有利的气象条件。 相似文献
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大樱桃 [Ｃｅｒａｓｕｓａｖｉｕｍ (Ｌ .)Ｍｏｅｎｃｈ]又称西洋樱桃、欧洲甜樱桃、甜樱桃、洋樱桃等。大樱桃花期较晚 ,不易受冻害 ,可连年丰产。由于果实个大、色艳、味美 ,市场销售价每千克 2 0元以上 ,有广阔的发展前景。但多数大樱桃品种成枝力弱 ,枝叶稀疏 ,进入盛果期晚 ,一般 7年以上 ,单位面积产量也不高。以上因素制约了大樱桃的发展。由于中国樱桃 [Ｃｅｒａｓｕｓｐｓｅｕｄｏｃｅｒａｓｕｓ(Ｌｉｎｄｌ)Ｇ .Ｄｏｎ]栽培较多 ,近几年栽培面积和产量增加 ,价格下跌至每千克 3～ 5元 ,效益下降。利用中国樱桃高接大樱桃可以扬长… 相似文献
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广西中小企业进入越南市场的SWOT分析 总被引：2，自引：0，他引：2
SWOT法是一种对企业有利因素和不利因素综合分析,从而发现问题,确定策略的科学的战略分析方法.广西的中小企业要进入越南市场,必须要进行优势、劣势、机遇、威胁等全面综合的分析,以制定正确的策略. 相似文献
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Five different viruses isolated from degenerating European beech of different forest sites of West Germany could be identified as cherry leaf roll virus, brome mosaic virus, potex and potyviruses. 相似文献
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《林业研究》2021,(4)
Subtropical forest in China has received much attention due to its complex geologic environment and bioclimatic heterogeneity.There have been very few studies addressing which climatic factors have shaped both distribution patterns and niche differentiation of species from this region.It also remains unclear whether phylogenetic niche conservatism retains in plant species from this biodiversityrich subtropical region in China.In this study,we used geographic occurrence records and bioclimatic factors of Prunus dielsiana(Rosaceae),a wild cherry species,combined with the classical ENM-based DIVA-GIS software to access contemporary distribution and richness patterns of its natural populations.The current distribution of P.dielsiana occupied a relatively wide range but exhibited an uneven pattern eastward in general,and the core distribution zone of its populations are projected to concentrate in the Wushan and Wuling Mountain ranges of western China.Hydrothermic variables,particularly the Temperature Seasonality(bio4)are screened out quantitatively to be the most influential factors that have shaped the current geographical patterns of P.dielsiana.By comparison with other sympatric families,climatic niche at regional scale showed a pattern of phylogenetic niche conservatism within cherry species of Ros aceae.The effect of habitat filtering from altitude is more significant than those of longitude and latitude.We conclude that habitat filtering dominated by limiting hydrothermic factors is the primary driving process of the diversity pattern of P.dielsiana in subtropical China. 相似文献
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Klaus Lorenz Caroline M. Preston Susan Krumrei Karl-Heinz Feger 《European Journal of Forest Research》2004,123(3):177-188
Litter decomposition was studied for 2 years in a mixed forest serving as a water protection area (Rhine-Neckar conurbation, SW Germany). Two experiments differing in initial dry weight equivalent in litterbags were set up: one to compare decomposition of European beech leaves (Fagus sylvatica) with common oak leaves (Quercus robur), and the other comparing decomposition of Scots pine needles (Pinus sylvestris) with black cherry leaves (Prunus serotina Ehrh.), respectively. Mass losses were greater for oak litter than for beech (75.0 versus 34.6%), and for cherry litter than for pine (94.6 versus 68.3%). In both experiments, a strong initial loss of soluble compounds occurred. The changes in litter N and P concentrations and the decrease in C-to-N ratio coincided with changes in residual mass. However, neither tannin and phenolic concentrations nor NMR could explain the pronounced variation in mass loss after 2 years. Differences in litter palatability and toughness, nutrient contents and other organic compounds may be responsible for the considerable differences in residual mass between litter types. The fast decay of black cherry leaves appears to play a major role in the present humus dynamics at the studied site. Since black cherry has a high N demand, which is mainly met by root uptake from the forest floor, this species is crucial for internal N cycling at this conurbation forest site. These effects together may significantly contribute to prevent nitrate leaching from the forest ecosystem which is subject to a continuous N deposition on an elevated level. 相似文献
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樱桃在在落叶果树中果实成熟最早,为"百果之先",正处春末夏初果品青黄不接的时期,樱桃填补了鲜果供应的空白。对丰富市场、均衡果品周年供应、满足人民消费需要方面起着重要作用。天水地区的气候条件适宜樱桃的种植,并且产量高、品质好,有较高的经济效益和社会效益,值得推广和发展。 相似文献
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Cherry laurel (Prunus laurocerasus) is a native plant species in Serbian forests, but is also widely used for ornamental plantings. Following two extremely wet summers in 2014 and 2015, in spring and summer of 2016 and 2017, numerous cherry laurel plants with symptoms indicative for Phytophthora diseases, like wilting and chlorosis of leaves, dieback and bleeding bark necroses, were recorded in a park in Belgrade and in two ornamental nurseries in central Serbia. From necrotic bark samples and rhizosphere soil, self‐sterile Phytophthora isolates with woolly colonies were obtained. Due to the production of ellipsoid and elongated, non‐papillate sporangia in water and of ornamented oogonia with two‐celled antheridia in mating tests with tester strains of both Phytophthora × cambivora and P. cryptogea, these isolates were identified as P. ×cambivora which was confirmed by ITS sequence analysis. Pathogenicity of P. ×cambivora from cherry laurel (PCCL) was tested by inoculating one‐year‐old seedlings of cherry laurel under the bark. P. ×cambivora from European beech (PCB), and isolates of P. cactorum (CAC), P. cryptogea (CRY), P. plurivora (PLU) and P. ×serendipita (SER) were included as comparison. Three and a half months after inoculation, nine of the twelve plants in PCB, three in PCCL and CAC and two in PLU declined with longitudinal necroses and chlorosis, wilting and premature shedding of leaves. These results demonstrate the ability of P. ×cambivora to infect and cause decline of cherry laurel plants. The particularly high aggressiveness of the P. ×cambivora isolate from beech shows that this pathogen poses a serious risk to cherry laurel in the rare natural communities of cherry laurel and beech in Serbia. 相似文献
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宝鸡市北坡区域位置显要,是宝鸡市的形象窗口。北坡景观绿化就是要提高绿化品位,改善人居和投资环境。本文以北坡绿化现状为基础,分析存在问题,提出了系统绿化、生态绿化、突出景观绿化、体现人文特色的绿化思路,因地制宜制定了景观绿化的＂二带二区＂总体布局,提出了造林、补植、抚育和改造四种绿化治理措施,选择了造林树种和配置方法,提出了相应的技术措施。 相似文献
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Initial sprouting, growth and mortality of European aspen and birch after selective coppicing in central Sweden 总被引：2，自引：0，他引：2
For reasons of aesthetics, sheltering, biodiversity, and children’s need of playgrounds, selective coppicing could be a useful and effective silvicultural method in urban areas. A randomised block experiment was carried out in three broad-leaved coppices situated within the fenced area of Arlanda Airport to compare a selective coppice regime (SCR), where all trees above a certain height limit were cut, with a traditional coppice regime, where all trees were felled. The effects of the treatments of the dominating tree species European aspen (Populus tremula L.) and birch (Betula pendula Roth and B. pubescens Ehrh.) were studied. During three growing seasons after performed treatment, the proportion of sprouting stools and root shooting of European aspen were reduced in SCR. Birch stools had fewer sprouts stool−1, and sprouts of both birch and European aspen tended to be shorter in SCR. There was a tendency that the sprout mortality was lower in SCR for both birch and European aspen. Residual stands of SCR consisted of proportionally less birch, and more rowan, bird cherry, oak and other species. Coppicing with single tree selection from above suppressed light demanding tree species and promoted the more shade-tolerant species compared to traditional coppicing. 相似文献
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大樱桃壮旺幼树不同修剪方法和促花技术试验 总被引：1，自引：0，他引：1
为了研究整形修剪对大樱桃早期丰产的影响,通过稀植园和密植园大樱桃壮旺幼树的修剪试验,明确长放修剪方法可节省用工,有利于树体生育,成花早、株产高,尤其适用于密植园的大樱桃栽培。开始采用长放修剪的树龄,密植园大樱桃树宜在2～3年生,稀植园樱桃树宜在株问粗距1．5～2m时进行,截放修剪方法适用于即需扩冠又要较早结果的大樱桃壮旺幼树。短截修剪方法修剪量大,不利于大樱桃壮旺幼树的生长发育,结果晚,株产低,且费工,但对栽后缓苗期树或衰弱树还是适用的。刻芽枝条上叶丛皲数量明显增加,花束状果枝增加。摘心的长枝花枝率和后下部叶丛枝的花枝率明显增加。 相似文献