共查询到20条相似文献，搜索用时 515 毫秒
1.
2.
位于三江源(新安江、富春江、钱塘江)六股尖北麓的鹤城乡新安源村,有一片神奇的古树水口林。走进参天绿荫、凉风习习的古林,空气变得异常纯净,让饱受城市雾霾荼毒的肺一下子得以自在呼吸,大脑也骤然亢奋灵动起来。新安源古林公园是中国现存面积最大、树种最多、树龄最长的水口林,面积达100亩,名贵树种有枫香、红豆杉、银杏、栾树、香榧等20种、共192棵. 相似文献
3.
2008年12月21日.内蒙古林业产业协会在呼和浩特市成立。国家林业局副局长张建龙、内蒙古自治区政府副主席郭启俊出席成立大会并为内蒙古林业产业协会揭牌。内蒙古林 相似文献
4.
5.
珍稀古树是国家的宝贵财富和重要的树种资源,查清其种类、数量及分布情况,研究其规律和特点,可为抢救濒危树种、开发利用宝贵资源,调整林业布局和制定保护法规提供科学依据.现将开县珍古稀古林资源的调查情况初报于后: 相似文献
6.
7.
指出了梅花是南京市花,有悠久的栽培历史。南京市古林公园作为山林公园,以梅花为特色,是市内最大的赏梅景区。结合多年栽培梅花经验,从历史渊源、栽培养护、病虫害防治等方面总结了其栽培管理要点,供相关人员参考。 相似文献
8.
张学全 《内蒙古林业调查设计》2013,36(3):96-99
古林箐自然保护区位于北回归线以南,哀牢山南端以东的滇东南高原向东南半岛延伸的结合部,南亚热带与热带的过渡地带。在这特殊的自然地理条件下,成为我国三大生物多样性中心之一的滇东南—桂西北的核心部位,区内有发育完整,保存完好的森林生态系统和丰富的生物资源。但在管理中存在许多方面问题,据此提出保护措施。 相似文献
9.
10.
一、前言高山小毛虫(Cosmotriche saxosimilis Lajonquiere)在分类上,隶属鳞翅目、枯叶蛾科、小毛虫属。国外未见报道,国内仅《中国蛾类图鉴》Ⅳ作过简短的介绍,因此,它的生物学特性及防治研究,尚属空白。 1984年秋,此虫在中甸县碧古林区海拔3800—4000米的天然冷杉水源林内大发生,为害长苞冷杉(Abies georgei),成灾面积达7万多亩。1985年春,由云南林科院主持,迪庆州林业局、中甸县林业局、省森林病虫防治检疫站参加,组成“高山小毛虫生物学特性的观察及防治研究”课题组,进行了为期三年的生物学特性观察和防治试验研究。 相似文献
11.
This paper describes a model for assessing the potential forsustained management of ancient woodland at the local landscapescale, based on the premise that a ‘normal’ foreststructure is the best option for integrating nature conservationwith provision of a regular supply of timber. The concept of‘normality’ is applied to clusters of small ancientwoods which are considered together and treated as a whole. Data on ancient woodland distribution are used from West Sussex,Essex and North Yorkshire. At ten sample points within eachcounty the woodland area within a 25-km2 block centred on thepoint was considered to see whether a normal forest structurecould be created and maintained by sustained management usinglikely minimum felling rates and average rotation lengths forthe main species for both high forest and coppice systems. Themodel was also tested for situations where small woods or woodswith conservation status were excluded from the system, as wellas for different minimum felling rates. The areas proposed forfelling within ancient semi-natural woods currently listed withinthe Woodland Grant Scheme (WGS) (II) are higher than can bemaintained in the longer term in West Sussex and Essex. The model provides a preliminary method for setting the contextof individual forestry schemes withn the wooded landscape asa whole. 相似文献
12.
Little is known about the influence of former agricultural use of soils on the forest recovery process in post-agricultural black alder (Alnus glutinosa) woods – the most fertile and the wettest forest habitats among the European temperate forest types. Thus, studies focusing on edaphic, hydrological and light conditions responsible for colonization mechanisms present in such woodlands adjoining ancient ones were undertaken in south-western Poland. In the 16 m2 quadrats of the 33 transects laid out perpendicularly across the ancient-recent forest boundary, data were collected on herb layer composition, chemical soil properties, as well as illumination level. Additionally, groundwater level in the spring months was recorded in piezometers. The number and cover of true woodland herbs were higher in ancient woods, regardless of forest type. Soils in ancient woodlands reached higher levels of Al3+, K+, cation exchange capacity (CEC), available K, P, and organic C, whereas their pH was lower. The illumination level of the forest floor was greater in recent woods. Linear regression showed that recent wood age had a negative effect on pH and base cations, but positive on Fe2+, Ca2+, available P and Mg, CEC, and on C and N contents. CCA results showed that woodland age, pH, humus type, groundwater level, available Mg and K were always among those variables having the highest contribution in explaining the distribution pattern of woodland species in recent woods. Total N and available P contents were always higher in ancient woodland soils than in recent, and their content grew with time. Thus, they cannot be treated as indicators of former agricultural use of recent alder wood soils. Urtica dioica, Poa trivialis and Galium aparine, the three competitive herbs, avoided sites with a high level of groundwater, combined with poor illumination level. In order to create the best possible conditions allowing for effective forest recovery in habitats of such high fertility, it is essential to maintain a good water regime and shade in the forest floor. This in turn reduces the competitive exclusion of woodland flora by the aggressive herbs and facilitates the immigration of typical woodland herbs. 相似文献
13.
14.
15.
16.
T. H. Sparks J. N. Greatorex-Davies J. O. Mountford M. L. Hall R. H. Marrs 《Forest Ecology and Management》1996,80(1-3):197-207
During 1985-6 the vegetation in the rides (forest tracks) of eight English lowland woods, planted on ancient woodland sites was surveyed. Shade was measured in each transect by hemispherical photography. Dicotyledonous species richness and the majority of dicot plant species declined as shade increased. The results for individual species compare favourably with Ellenberg's (L) value in most cases, and a method is suggested for modifying Ellenberg's data in the light of new information. The woodlands contained species of both open and shaded habitats and communities were influenced by soil acidity. Because shade in woodland rides increases as the trees mature, theory states that there will almost certainly be a reduction in plant species diversity. Butterfly populations would also be adversely affected, partly because of the reduction in direct sunlight, and partly because their larval foodplants decline in both quantity and quality since they are generally associated with low to moderate shade. 相似文献
17.
18.
对安宁市集体林权制度改革后林地管理工作的思考 总被引：2，自引：1，他引：1
由于安宁市林地管理采取集体统一和模式化管理的形式以及集体林权制度改革后均山到户,给林地管理工作带来了一些新问题,加大了对林地监管的难度.文中分析了林改后林地管理中凸现的实际权利不到位,林权流转平台尚未完善,林农主体地位得不到兑现,林权纠纷解决机制不完善,管理队伍不健全等问题.藉此,提出稳定林权,还权于民,规范林权流转机制,完善林业纠纷解决机制,依法依规保护管理林地,明确管理责任等加强林地管理的措施. 相似文献
19.
20.
Morecroft Michael D.; Stokes Victoria J.; Taylor Michele E.; Morison James I.L. 《Forestry》2008,81(1):59-74
Sycamore (Acer pseudoplatanus L.) is an invasive, non-nativespecies in Great Britain and its management in conservationareas is controversial. Climate change adds further uncertaintyto decision making. We investigated the role of management historyin determining present-day abundance and the effects of climaticvariability on growth, photosynthesis and phenology at WythamWoods, a UK Environmental Change Network (ECN) monitoring site.Relatively few sycamore trees were found in undisturbed ancient,semi-natural woodland and recent plantations, despite beingcommon in other areas of the site. Sycamore grew more slowlythan ash (Fraxinus excelsior L.), its principal competitor,but at a similar rate to pedunculate oak (Quercus robur L.)in the period 1993–2005. There were fewer sycamore thanash seedlings, regardless of which species dominated the canopy.Growth of sycamore was slower in dry periods than wet ones andlower photosynthetic rates were measured in canopy leaves underdry compared with wet soil conditions. This study thereforesuggests that sycamore does not present a serious threat toundisturbed ancient woodland on the site and that it may eventuallydecline in areas of the site where it competes with ash, inthe absence of disturbance. It may also decline under climatechange if summer droughts become more frequent. 相似文献