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1.
<正>在林业血防"十二五"开局之际,安徽省党组决定加强林业血防技术培训,全面促进林业血防工程建设,这是林业血防形势发展的需要,也充分体现了厅党组对林业血防工作的重视和决心。1充分认识林业血防技术培  相似文献   

2.
在分析了罗山县林业生产现状和存在问题的基础上,论述了该县林业发展的有利条件,探讨了林业发展的前景,并提出了该县应从根本上转变对林业的认识等发展林业的对策  相似文献   

3.
<正>这些年来,国家对林业建设非常重视,先后启动实施了天然林保护等六大生态工程。以胡锦涛同志为总书记的党中央明确提出“林业是一项重要的公益事业和基础产业”。在贯彻可持续发展战略中,要赋予林业以重要地位;在生态建设中要赋予林业以首要地位;在西部大开发中,要赋予林业以基础地位,实施以生态建设为主的林业发展战略。这既为林业发展指明了方向,也进一步明确了林业在全面建设小康社会,加快推进社会主义现代化进程中不可替代的重要地位和作用。强化林业生态工程建设中的科技支撑,是保障林业生态建设质量和水平的关键。  相似文献   

4.
文章分析了现代城市林业的基本概念和研究现状,以大连市为例阐述了现代城市林业发展现状,并详细探讨了大连现代城市林业的地域结构和空间功能,在此基础上构筑了现代城市林业的空间发展模型,在理论上探讨现代城市林业的地域结构和空间功能。  相似文献   

5.
以可持续发展理论为指导思想,从论述可持续林业是现代林业发展的新趋势入手,探讨了可持续林业的涵义、目标和内容,并提出了林业可持续发展的实施举措  相似文献   

6.
<正> 于1978年召开的第八届世界林业大会(主题为“森林为人民”)以后,林业的焦点已经从传统的生产性林业转移到以农村综合发展为主的林业活动上。以东南亚国家为代表的一些发展中国家开始采取林业与农村社会和经济综合发展的林业经营模式——社区林业为其林业发展战略,注意吸收当地社区和  相似文献   

7.
随着我国市场经济的不断发展和完善及人们对回归大自然的渴望,林业越来越受到人们的青睐和重视。在中央对林业有关政策的支持、林业工作者的辛勤努力下,新时期的林业正以跨越式的形势向前发展,在多行业中越来越显现出他的“青春活力”。然而,除林业以外,很少有人对林业比较熟悉和了解,只是把林业作为经济和改善人类生存环境的一个辅助因子,对林业的重要性缺乏足够的认识,不清楚林业在国民经济和人类生存中的重要地位。因此,笔者认为加大对林业各方面的宣传很有必要,在“自我宣传”和“宣传自我”,采取多形式、多内容的宣传,对林业的发展将有…  相似文献   

8.
在简述林业与血防建设关系的基础上,强调了林业血防工程的重要性,着重论述了科技支撑对林业血防工程建设的推动、技术保障、引导和示范作用。总结了安徽省林业血防工程的成效,充分体现科技支撑在林业血防建设中的主导地位。  相似文献   

9.
本文根据当前新疆林业存在的“两危”(森林资源危机和企业经济危困)和干旱区林业的基本特征,遵循新疆林业建设“十二字”方针及深化改革精神,对本世纪末新疆林业发展战略目标、指导思想和战略部署,提出探讨性意见。  相似文献   

10.
《中共中央国务院关于加快林业发展的决定》中 ,把坚持科教兴林作为加快林业发展的基本方针 ,并把林业技术推广工作放在了突出的位置 ,明确指出 :“林业重点工程建设与林业技术推广要同步设计、同步实施、同步验收。”这就要求各级领导、林业技术推广部门要转变观念、提高认识 ,充分发挥行业优势 ,积极投入到林业重点工程建设中去 ,真正实现林业重点工程与林业技术推广“三同步”。几年来 ,我市实施的林业重点工程有退耕还林、长江及淮河流域防护林、自然保护区建设和速生丰产林建设等 5项林业重点工程。由于各级党委、政府的高度重视和业务…  相似文献   

11.
不同植被类型的土壤水分对黄土高原的影响   总被引:9,自引:0,他引:9  
Water stored in deep loess soil is one of the most important resources regulating vegetation growth in the semi-arid area of the Loess Plateau, but planted shrub and forest often disrupt the natural water cycle and in turn influence plant growth. The purpose of this study was to examine the effects of main vegetation types on soil moisture and its inter-annual change. Soil moisture in 0–10 m depth of six vegetation types, i.e., crop, grass, planted shrub of caragana, planted forests of arborvitae, pine and the mixture of pine and arborvitae were measured in 2001, 2005 and 2006. Soil moisture in about 0–3 m of cropland and about 0–2 m of other vegetation types varied inter-annually dependent on annual precipitation, but was stable inter-annually below these depths. In 0–2 m, soil moisture of cropland was significantly greater than those of all other vegetation types, and there were no significant differences among other vegetation types. In 2–10 m, there was no significant moisture difference between cropland and grassland, but the soil moistures under both of them were significantly higher than those of planted shrub and forests. The planted shrub and forests had depleted soil moisture below 2 m to or near permanent wilting point, and there were no significant moisture differences among forest types. The soil moisture of caragana shrub was significantly lower than those of forests, but the absolute difference was very small. The results of this study implicated that the planted shrub and forests had depleted deep soil moisture to the lowest limits to which they could extract and they lived mainly on present year precipitation for transpiration.  相似文献   

12.
Water stored in deep loess soil is one of the most important resources regulating vegetation growth in the semi-arid area of the Loess Plateau, but planted shrub and forest often disrupt the natural water cycle and in turn influence plant growth. The purpose of this study was to examine the effects of main vegetation types on soil moisture and its inter- annual change. Soil moisture in 0–10 m depth of six vegetation types, i.e., crop, grass, planted shrub of caragana, planted forests of arborvitae, pine and the mixture of pine and arborvitae were measured in 2001, 2005 and 2006. Soil moisture in about 0–3 m of cropland and about 0–2 m of other vegetation types varied inter-annually dependent on annual precipitation, but was stable inter-annually below these depths. In 0–2 m, soil moisture of cropland was significantly greater than those of all other vegetation types, and there were no significant differences among other vegetation types. In 2–10 m, there was no significant moisture difference between cropland and grassland, but the soil moistures under both of them were significantly higher than those of planted shrub and forests. The planted shrub and forests had depleted soil moisture below 2 m to or near permanent wilting point, and there were no significant moisture differences among forest types. The soil moisture of caragana shrub was significantly lower than those of forests, but the absolute difference was very small. The results of this study implicated that the planted shrub and forests had depleted deep soil moisture to the lowest limits to which they could extract and they lived mainly on present year precipitation for transpiration.  相似文献   

13.
不同植被类型对厚层黄土剖面水分含量的影响   总被引:16,自引:1,他引:15  
王志强  刘宝元  张岩 《地理学报》2008,63(7):703-713
为了研究不同植被类型土壤水分差异和土壤水分的年际变化特征, 对陕西省绥德县境 内的农地、天然草地、人工柠条林、人工侧柏林、人工油松林、人工油松侧柏混交林地0~10 m 土壤剖面的土壤水分含量进行了测定与分析。农地土壤约在3 m 以上、其他植被类型约在 2 m 以上土层的土壤含水量随年降雨量的大小存在年际变化, 且农地土壤含水量显著高于其 他植被类型, 其他植被类型间无显著性差异。0~2 m 土层农地土壤水分在不同测定年份始终在易效水以上, 但其他植被类型的土壤水分随降雨量的不同变化于难效- 无效水与易效水之间。农地3 m、其他植被类型约2 m 以下的土壤含水量无显著性年际变化。农地与天然草地 土壤含水量显著高于其他人工林植被, 但二者含水量之间无显著差异, 土壤水分都属易效水 范围。人工柠条灌木林土壤水分显著低于其他植被类型, 人工侧柏林、人工油松林和人工油 松侧柏混交林之间土壤含水量无显著性差异。人工柠条林土壤水分属于难效-无效水范围, 人工乔木林接近难效-无效水范围。  相似文献   

14.
人工措施对川中丘陵区防护林建设的影响   总被引:2,自引:2,他引:0  
人工措施对防护林建设初期的影响,主要表现在保存率,林木生长,林分结构等方面,而这些都与防护林效益密切相关,为此,提出了营建和管理防护林中应注意的问题。  相似文献   

15.
对安庆市南埂林场长江沿岸杨树抑螺防病林3年生、8年生和20年生林地上空间昆虫群落的种群组成和多样性进行了调查。结果表明,在3种不同林龄林分之间,地上空间昆虫种群组成的差异表现为,在目一级分类单元组成上,3种不同林龄林分具有很高的共性,在科和种的单元上,不同林龄林分之间的差异大小依次为:3年生与20年生林分之间>3年生与8年生林分之间>8年生与20年生林分之间。随着林分林龄的增加,林内地上空间昆虫丰富度指数、Shannon-Wiener指数明显降低。不同林龄林分地上空间昆虫种群的均匀度指数与林分林龄无明显的相关性,其中20年生林分昆虫种群的均匀度指数显著低于8年生和3年生的林分,而8年生和3年生林分之间没有显著差异。  相似文献   

16.
在25 a生的马尾松林下分别套种1 a生的火力楠、闽粤栲、苦槠、格氏栲、青栲和拉氏栲幼苗,经过16 a的培育后形成了郁闭的针阔混交异龄林,分别以马-火(Pm-Mm)、马-闽(Pm-Cf)、马-苦(Pm-Cs)、马-格(Pm-Ck)、马-青(Pm-Cm)、马-拉(Pm-Cl)表示。对上述6种混交林的蓄积量、生物量、凋落物、物种多样性、土壤肥力等10个指标进行分析和综合,以揭示混交林的经济效益、生态效益和地力维持。在此基础上,应用层次分析法(AHP)确定各指标的权重,构建多目标决策模型,对混交林综合效益进行了评价。根据综合评价值的大小,各混交林的优劣顺序为:马-闽→马-苦→马-拉→马-青→马-格→马-火,从而为马尾松混交模式的选择提供科学依据。  相似文献   

17.
贵州省森林资源动态变化   总被引:7,自引:1,他引:7  
依据贵州省林业调查规划院1979、1984、1990、1995、2000年5次森林资源连续清查资料,从森林资源面积、蓄积量、组成结构等方面总结了该省近20年间森林资源动态变化的详细资料,并对变化的原因进行了分析。结果表明,20世纪70年代末至80年代末,林业用地面积、天然林面积与蓄积量均呈下降趋势;其后,由于贵州省政府及林业部门的高度重视,实施一系列林业生态保护与可持续发展工程,如国家“长江防护林工程”、“珠江防护林工程”等,贵州森林资源自1990年以来持续稳定增长,促进了生态环境改善  相似文献   

18.
Afforestation in China’s subtropics plays an important role in sequestering CO2 from the atmosphere and in storage of soil carbon (C). Compared with natural forests, plantation forests have lower soil organic carbon (SOC) content and great potential to store more C. To better evaluate the effects of afforestation on soil C turnover, we investigated SOC and its stable C isotope (δ13C) composition in three planted forests at Qianyanzhou Ecological Experimental Station in southern China. Litter and soil samples were collected and analyzed for total organic C, δ13C and total nitrogen. Similarly to the vertical distribution of SOC in natural forests, SOC concentrations decrease exponentially with depth. The land cover type (grassland) before plantation had a significant influence on the vertical distribution of SOC. The SOC δ13C composition of the upper soil layer of two plantation forests has been mainly affected by the grass biomass 13C composition. Soil profiles with a change in photosynthetic pathway had a more complex 13C isotope composition distribution. During the 20 years after plantation establishment, the soil organic matter sources influenced both the δ13C distribution with depth, and C replacement. The upper soil layer SOC turnover in masson pine (a mean 34% of replacement in the 10 cm after 20 years) was more than twice as fast as that of slash pine (16% of replacement) under subtropical conditions. The results demonstrate that masson pine and slash pine plantations cannot rapidly sequester SOC into long-term storage pools in subtropical China.  相似文献   

19.
中国亚热带地区造林对土壤碳周转的影响   总被引:5,自引:1,他引:4  
Afforestation in China’s subtropics plays an important role in sequestering CO2 from the atmosphere and in storage of soil carbon (C). Compared with natural forests,plantation forests have lower soil organic carbon (SOC) content and great potential to store more C. To better evaluate the effects of afforestation on soil C turnover,we investigated SOC and its stable C isotope (δ13C) composition in three planted forests at Qianyanzhou Ecological Experimental Station in southern China. Litter and soil samples were collected and analyzed for total organic C,δ13C and total nitrogen. Similarly to the vertical distribution of SOC in natural forests,SOC concentrations decrease exponentially with depth. The land cover type (grassland) before plantation had a significant influence on the vertical distribution of SOC. The SOC ?13C composition of the upper soil layer of two plantation forests has been mainly affected by the grass biomass 13C composition. Soil profiles with a change in photosynthetic pathway had a more complex 13C isotope composition distribution. During the 20 years after plantation establishment,the soil organic matter sources influenced both the δ13C distribution with depth,and C replacement. The upper soil layer SOC turnover in masson pine (a mean 34% of replacement in the 10 cm after 20 years) was more than twice as fast as that of slash pine (16% of replacement) under subtropical conditions. The results demonstrate that masson pine and slash pine plantations cannot rapidly sequester SOC into long-term storage pools in subtropical China.  相似文献   

20.
兰州南北两山绿化区植物与植被类型初查   总被引:10,自引:7,他引:3  
武利玉  苏世平  王蕙 《中国沙漠》2006,26(4):564-568
通过对兰州南北两山环境绿化工程区进行植物、植被类型调查,结果表明:该项目区内植物资源相对丰富,有植物185种,分属于56科;区内植物生长状况良好,植物群落趋向多元化,且稳定性增加;按照植物群落学—生态学原则,并参考中国植被分类系统,将工程区内植被类型划分为9种类型,即 2种天然植被类型和7种人工植被类型。根据当前所造林分多为结构单一的纯林的现状,认为今后在南北两山进行植树造林应考虑营造混交林,以提高林分稳定性和抵御病虫害的能力,并积极采用人工措施促进森林更新。  相似文献   

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