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1.
文章扼要阐述了卫星遥感影像图在森林资源二类调查中的作用、影像特征、成像规律及在使用卫星遥感影像图过程中应注意的问题。  相似文献   

2.
介绍获取网上卫星影像图和用VB6.0程序对下载的卫星影像图批量配准、拼接的简单方法,适合基层林业工作者在实际工作中应用。  相似文献   

3.
对TM卫星影像图在新林林业局森林资源二类复查中的使用效果进行了分析。表明应用TM卫星影像图进行目视判读森林土地类型具有较高的准确率,在与旧航片结合使用时可提高小班区划质量。  相似文献   

4.
TM卫星影像图在荒漠化土地普查与监测中的应用   总被引:2,自引:0,他引:2  
采用TM卫星影像图室内目视解译和实地验证以及地形图辅助实地调绘相结合的方法,进行了青海省荒漠化土地普查与监测体系建立工作,摸清了家底,达到了预期目的。全国率先大范围应用TM卫星影像图进行荒漠化土地普查和建立监测体系,表明方法是实用可行的。  相似文献   

5.
基于谷歌地图资源的ArcGIS林业基本图的制作   总被引:1,自引:1,他引:0  
通过基于谷歌地图免费影像资源制作林业的基本图的方法,提供了一种具有直观和可离线浏览和数据量小等特点的林业基本图,为林业基层工作者提供了一种方便快捷和经济的基于卫星影像资源的ArcGIS林业基本图的制作方法。  相似文献   

6.
天地图资源是国内最具有权威性的免费卫星影像资源,其卫星影像已达到0.54米分辨率,且能保持一定的跟新速度。通过利用天地图的影像资源,结合移动设备制作出可供基层林业工作中使用的可移动外业调查和导航用图,能有效提高林业基层工作人员外业调查的工作效率。  相似文献   

7.
以芒市2019年卫星影像及2019年林地一张图成果为研究对象,基于深度学习的卫星影像分类研究,构建森林资源分类识别模型,以提高森林资源监测能力.将裁剪后的芒市2019年卫星影像分有林地、灌木林地、未成林地及耕地、建设用地5个类别导入自定义的ResNet18模型进行深度学习,并对学习结果进行验证.实验结果显示,在模型训练...  相似文献   

8.
勘界勾图是集体林林权制度改革工作中专业性、技术性最强的工作,而实际从事这项工作的大多为非专业技术人员,他们在实地勘界勾图时往往难以下笔.采用卫星影像图与地形图进行简单叠加应用,能较好地解决林改中非专业技术人员识图、勾图难的问题.文章就采用卫星影像图与地形图简单叠加的具体方法进行了论述.  相似文献   

9.
浅谈影像叠加图在林地保护利用规划中的应用   总被引:1,自引:0,他引:1  
在现代社会经济发展中,传统的地形图更新速度远远不能跟上现代林业建设和数字林业发展的步伐,利用卫星遥感影像数据和航空摄影制作数字正射影像地图(Digital OrthophotoMap,缩写DOM),再叠加上矢量化的坐标网格地形图数据图层及行政边界数据图层形成的叠加图,进行林地保护利用规划的外业调查,能极大地减少外业调查的工作量。本文主要探讨利用卫星遥感影像的数字正射影像图为底图制作的叠加图,在林地保护利用规划中的应用。  相似文献   

10.
ArcGIS可视域分析在瞭望台管理中的应用   总被引:6,自引:0,他引:6  
利用ArcGIS地理信息系统平台,结合空间分析的建模理论,以广州市白云山SPOT卫星影像图和全要素数字图数据为材料,阐述了可视域分析的过程,得出了遥感影像和数字化地形图相结合进行可视域分析的方法,输出的通视图清晰直观,为广州市森林防火信息系统瞭望台管理提供了可靠的基础决策信息。  相似文献   

11.
重庆地区桉树无性系引种效果评价   总被引:2,自引:0,他引:2  
以无性系DH32-29、EC14、C6、巨按、尾叶按U6为参试品种,对参试品种3年林的各项生长指标、抗逆性指标等进行了系统观测、评价。结果表明,在参试品种中,DH32—29的平均胸径、树高、材积生长量均最大,分别达到14.01cm,13.8m和0.1061m^3,DH32—29的耐高温干旱能力最强,在连续42℃高温下,造林保存率最高达89.26%;低温胁迫条件下,DH32—29耐寒性最强,寒害指数和寒害率均为0。试验证明,DH32—29可作为重庆西部低海拔生态区域的优良种源,并可在该地区退耕还林、速生丰产林、园林绿化中加以应用。  相似文献   

12.
森林冠层结构与功能及其时空变化研究进展*   总被引:16,自引:0,他引:16  
林冠是森林与外界环境相互作用最直接和最活跃的界面层 ,同时 ,它本身又承载了森林生物多样性的主体部分。森林冠层研究的方法和技术在近些年取得了长足发展 ,从而促进了有关林冠结构与功能的研究。这些研究深化了人们对于林冠结构与光能截获以及群落干物质积累之间关系的认识 ,同时 ,对于森林冠层的物质循环和能量传输以及冠层内各营养级之间相互关系动态也有了更为深入的理解。考察森林冠层的结构与功能及其时空变化是深入理解整个森林生态系统的格局、过程及其运作机制的重要基础。  相似文献   

13.
The persistence of the four herbicides atrazine, hexazinone, lenacil and linuron was studied in forest nursery soils. The adsorption capacities of the soils for the chemicals were described by the distribution coefficients kj and koc. Due to the low content of organic matter in the soils the kavalues were low, in several cases being <1 for hexazinone. Hexazinone also had the lowest k oc‐value (30) while the other substances had koc ‐values within the range 200–400. In some cases hexazinone showed great mobility under field conditions. The formula c=co‐kt1/2 was used to describe the disappearance of the herbicides from the various soils. The rate of degradation of the four herbicides correlated well with the rate of respiration in the same soils in laboratory experiments, and for linuron reasonably well also in field experiments. In the field experiments the herbicides penetrated the top soil layer. In the subsoil the risk of further transport downward to the drainage system or ground water increased, especially for hexazinone. Linuron as well as the fungicides maneb and tolylfluanid suppressed the decomposition rate of hexazinone in laboratory experiments.  相似文献   

14.
本文记述了中国松叶蜂昆虫两新种,马尾松吉松叶蜂和油松吉松叶蜂。文中附有形态特征图4幅。  相似文献   

15.
彩色豆马勃与松树形成内外生菌根的研究   总被引:9,自引:0,他引:9       下载免费PDF全文
采用组培菌根合成技术、纸 三明治菌根快速合成技术和圃地截根菌根化育苗技术使彩色豆马勃RG310和RG49菌株在马尾松、火炬松、湿地松上形成内外生菌根,不同菌根化技术形成菌根的过程和类型有差异。在组培菌根合成的条件下,菌与根接触后的第3~4d首先开始形成菌丝套,第8d开始形成哈蒂氏网,第18d菌丝进入皮层细胞内,哈蒂氏网由单列变为多列菌丝细胞组成;采用纸 三明治菌根快速合成技术进行截根菌根化,促进了菌根真菌的定殖,以截面伤口侵入为主要的侵入方式,扩大了根内外菌根侵染区(MIZ),定殖、侵染同时发生,菌丝套、哈蒂氏网和胞内菌丝结构几乎同时形成,仅在2.5h内就开始形成,菌根真菌的菌丝进入了内外皮层和髓部;采用圃地截根菌根化育苗技术,仍然形成内外生菌根,但菌丝不侵入内皮层以内的根组织。根据研究提出"菌根类型"假说,即树木形成的菌根类型不但随菌根真菌和树木种类而异,而且随菌根化方法、生态条件等其它因子而异。  相似文献   

16.
Martínez Pastur  G.  Arena  M.  Curvetto  N.  Zappacosta  D.  Eliasco  E. 《New Forests》2003,26(3):201-215
In vitro rooting constitutes a difficult step during the micropropagation process of forest species. The successive media culture technique represents one way to overcome this barrier and includes modifying physical (e.g. photoperiod) and chemical (e.g. flavonoids) factors during the rooting phases. The aim of this study was to obtain a successive media protocol based on the incorporation of flavonoids during the in vitro rooting of Nothofagus nervosa. The factors evaluated were the type, concentration, and combination of flavonoids in relation to the rooting phases, the presence of IBA in the culture medium, the photoperiod, and the effect of flavonoids on total tissue peroxidase activity. The photoperiod used included a darkness period during the rooting induction stage and the presence of 0.61 µMIBA in the culture medium. The results showed that flavonoid incorporation at a concentration of 20 µM accelerated the appearance of roots and improved the quality of the already formed ones. Each type and concentration of flavonoid produced different responses, with (±)naringenin giving the best results. The latter caused a peak in the peroxidase activity that was absent in the control treatments. This work allowed identifying an optimized rooting protocol through a successive media culture technique that improved the speed of appearance, as well as the quantity and quality of roots for a single N. nervosa clone.  相似文献   

17.
野生动物所有权是所有权的一种,它与其他所有权的区别在于客体的不同。文章阐述了野生动物的内涵,分析了野生动物的分类和野生动物与野生动物资源的区别。在明确野生动物含义的基础上,提出了野生动物所有权的概念,深入论述了野生动物所有权与野生动物资源所有权的差异和联系,并对野生动物所有权的主体、客体、内容进行了分析。  相似文献   

18.
Senbeta  Feyera  Teketay  Demel  Näslund  Bert-Åke 《New Forests》2002,24(2):131-145
Regeneration of native woody species was studied in the plantations and the adjacent natural forest at Munessa-Shashemene Forest Project Area, Ethiopia. The aim of the study was to test the hypothesis that tree plantations foster regeneration of native woody species. A total of 60 plots, having 10 × 10 m area each, were studied in monoculture plantations of 4 exotic species (Cupressus lusitanica, Eucalyptus globulus, E. saligna, Pinus patula) and an adjacent natural forest. Ages of the plantations ranged between 9 and 28 years. Soil seed bank analysis was also undertaken from soil samples collected in each of the 60 plots to examine the similarity between the soil seed flora and aboveground vegetation. A total of 56 naturally regenerated woody species were recorded beneath all plantation stands with densities ranging between 2300 and 18650 individuals / ha in different stands. There was a significant difference among plantation stands with regard to understorey density (standard deviation: 4836 ± 1341). Vegetation diversity was assessed through analyses of floristic composition, species richness and abundance. Generally, seedling populations were the most abundant components of the regeneration in most of the plantation stands, forming 68 % of the total regeneration count in all stands. A total of 77 plant species represented by 44 herbs, 13 woody species, 8 grasses and 12 unidentified species were recorded in the soil seed bank from all stands. Similarity between the soil seed bank and aboveground flora was very low implying that the role of soil seed banks is negligible rather dispersal plays an important role in the process of regeneration. These results support the concept that forest plantations can foster the regeneration of native woody species, thereby increasing biological diversity, provided that there are seed sources in the vicinity of the plantations.  相似文献   

19.
The sawmill industry is a very important link in the Mozambique forest products value chain, but the industry is characterized by undeveloped processing technology and high-volume export of almost unrefined logs. The low volume yield of sawn timber has been identified as a critical gap in the technological development of the industry. To improve the profitability of the industry, there is thus a need to develop methods and techniques that improve the yield. In this paper, different positioning of logs prior to sawing and the possibility of increasing the volume yield of crooked logs by bucking the logs before sawing have been studied. A computer simulation was used to study the cant-sawing and through-and-through sawing of the logs to determine the volume yield of sawn timber from the jambirre (Millettia stuhlmannii Taub.) and umbila (Pterocarpus angolensis DC.) species. The optimal position, i.e. the position of the log before sawing that gives the highest volume yield of sawn timber for a given sawing pattern when the positioning parameters, offset, skew and rotation, are considered gave a considerable higher volume yield than the horns-down position. By bucking very crooked logs and using the horns-down positioning before sawing, the volume yield can be of the same magnitude as that obtained by optimal positioning on full-length (un-bucked) logs. The bucking reduces the crook of the logs and hence increases the volume yield of sawn timber.  相似文献   

20.
Regeneration of beech (Fagus crenata) forests depends on the formation of canopy gaps. However, in Japan Sea-type beech forests, a dwarf bamboo (Sasa kurilensis) conspicuously occupies sunny gaps. Therefore,F. crenata seedlings must escape the severe interference ofS. kurilensis in the gaps and persist beneath a closed canopy of the beech forest. We hypothesized that the growth ofF. crenata seedlings in the understory would be favored by their being more plastic thanS. kurilensis in photosynthetic and morphological traits, which would support the matter production ofF. crenata seedlings in a wide range of light availabilities. To examine this hypothesis, the photosynthetic-light response of individual leaves and the biomass allocation in aboveground parts (i.e., the culm/foliage ratio) were surveyed at sites with contrasting light availabilities in a Japan Sea-type beech forest in central Japan. InF. crenata, photosynthetic light utilization efficiency at relatively low light was greater, and the dark respiration rate was smaller in the leaves of seedlings (10 cm in height) beneath the closed canopy than in the leaves of saplings at the sunny forest edge. The culm/foliage (C/F) ratio of theF. crenata seedlings at the shady site was small, suggesting effective matter-production beneath the beech canopy. On the other hand,S. kurilensis both in the gap and beneath the beech canopy showed low plasticity in photosynthesis and the culm/foliage ratio. Because the shoot density ofS. kurilensis was smaller beneath the beech canopy than in the gap, the light availability at the bottom of theS. kurilensis layer was greater beneath the beech canopy. These results suggest that the photosynthetic productivity of theF. crenata seedlings would be enough for the seedlings to survive in the understory with a low density ofS. kurilensis shoots beneath the closed beech canopy.  相似文献   

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