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1.
Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%; the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented. 相似文献
2.
Forests in the Changbai Mountains are important timber sources for economic development of the society and provide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin Province based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%; the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and protecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented. 相似文献
3.
Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in China is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR. 相似文献
4.
Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in China is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR®, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR®. 相似文献
5.
Based on forest inventory data and a variety of spatial data layers, including topographic maps, forest type maps, forest themes, etc., a multilevel decision-support system (DSS) for forest resource management was developed for Shangzhi National Forestry Bureau, Heilongjiang Province, China. This paper induced the procedure of the DSS development and its main functions, including displaying, cartography, dual-comprehensive querying of spatial and attribute data, GPS positioning, statistical analysis, updating resource data, etc. The applications of the DSS in resources analysis and management proved effective both in forestry bureau and forest farm levels. Traditional approaches of forest resource management were accordingly updated and the digitization of forest management was realized in deed for state-owned forest industries. The system provides a basis for rational forest management towards sustainable forestry by means of stratified management. 相似文献
6.
Based on forest inventory data and a variety of spatial data layers, including topographic maps, forest type maps, forest themes, etc., a multilevel decision-support system (DSS) for forest resource management was developed for Shangzhi National Forestry Bureau, Heilongjiang Province, China. This paper induced the procedure of the DSS development and its main functions, including displaying, cartography, dual-comprehensive querying of spatial and attribute data, GPS positioning, statistical analysis, updating resource data, etc. The applications of the DSS in resources analysis and management proved effective both in forestry bureau and forest farm levels. Traditional approaches of forest resource management were accordingly updated and the digitization of forest management was realized in deed for state-owned forest industries. The system provides a basis for rational forest management towards sustainable forestry by means of stratified management. 相似文献
7.
在生态环境现状调查资料和相关研究成果的基础上,选择有区域代表性的生态因子,借助先进的GIS技术,采用因子叠加法,对焦作市的生态敏感性进行深入分析,建立了焦作市生态敏感性模型.按生态敏感度的高低将研究区划分为最敏感区、次敏感区、弱敏感区和非敏感区4个等级,提出分区保护与建设的建议,为研究区空间功能区划和区域生态环境的保护与治理提供有价值的参考依据.研究结果表明,最敏感区和次敏感区面积占研究区总面积的30.7%,显示研究区生态敏感性总体适中. 相似文献
8.
《林海雪原》生动地表现了解放军小分队创造的惊人奇迹,热情地讴歌了他们突破险中险,历经难中难,英勇无畏的革命英雄主义精神,故事充满浓厚的传奇色彩,引人入胜。在许多方面刻意学习中国传统古典小说的叙事模式,这是《林海雪原》成功的重要因素之一。 相似文献
9.
将地理信息系统(GIS)和遥感技术(Rs)相结合,利用地质图、土壤图、土地利用图、坡度图、坡向图对长白山地区进行了山体滑坡易发程度分析.首先基于遥感技术对长白山地区的卫星图像进行了分类,并绘制了土地利用图,然后用长白山地区的数字高程模型分别获取了坡度和坡向信息;其次利用AHP技术计算了5种山体滑坡影响因子的重要度,结果显示坡度重要度最高,坡向重要度最低;最后根据山体滑坡影响因子的重要度,使用GIS的栅格数据叠置功能绘制了山体滑坡易发区划图,图中显示最危险区域(危险度≥O.9)主要分布在集安市、临江市和和龙市周围的山区地带中靠近中朝边界的地区. 相似文献
10.
Quantitatively estimating soil erosion with an integration of geographic information system (GIS) and the revised universal soil loss equation (RUSLE) under four different exposed soil proportion scenarios caused by forest management practices was studied at Jianchang Forest Farm. The GIS provided means of input data generation required by RUSLE model and allowed a spatial assessment of the erosion hazard over the study area. Four exposed soil proportion scenarios of 5%, 10%, 20% and 30% were tested with the GIS-based RUSLE model to evaluate soil erosion hazard. The predicted soil erosion potentials were classified into five categories in order to provide valuable aids for management planning. 相似文献
11.
Quantitatively estimating soil erosion with an integration of geographic information system (GIS) and the revised universal soil loss equation (RUSLE) under four different exposed soil proportion scenarios caused by forest management practices was studied at Jianchang Forest Farm. The GIS provided means of input data generation required by RUSLE model and allowed a spatial assessment of the erosion hazard over the study area. Four exposed soil proportion scenarios of 5%, 10%, 20% and 30% were tested with the GIS-based RUSLE model to evaluate soil erosion hazard. The predicted soil erosion potentials were classified into five categories in order to provide valuable aids for management planning. 相似文献
12.
Study on the fossil plants and the palynoiogical assemblage is the basic botanical research on the coalbearing strata. The practice indicate that comprehensive data from the study on the fusinized wood fossil, the phyterals and the analysis of dispersed cuticles will effecuvely improve the level of the study on the coal-bearing strata as a whole. 相似文献
13.
黑龙江杂岩主要由蓝闪石片岩构成,蓝闪石片岩主要包括绿帘石、绿泥石、钠长石、钠质角闪石、多硅白云母和石英以及为数不多的榍石、钛铁矿和黑硬绿泥石。其中,钠质角闪石包括蓝闪石和镁质钠闪石。变质条件的压力(P)-温度(T)评价条件为400~425℃和0.69~0.86MPa,对应岩相为绿帘-蓝闪石片岩相。黑龙江杂岩蓝闪石片岩的地球化学研究表明,其原岩是可与洋岛型(OIB)玄武岩和一些洋中脊型(E-MORB)玄武岩相对比的大洋玄武岩,这说明黑龙江杂岩蓝闪石片岩的玄武岩原岩是在海底山或者在大洋隆起条件下由富集源形成的;具有洋岛型玄武岩地球化学特征的变质玄武岩以及富锰的变质燧石、大理石、变质硬砂岩和蛇绿岩鳞片的加入证明黑龙江杂岩是消减—增生杂岩,它含有变形洋壳的碎块和在被改造的前震旦纪佳木斯岩体西边缘上形成于侏罗纪的增生楔岩石;黑龙江杂岩在原岩成分上可与活动大陆边缘许多增生的杂岩相当。 相似文献
14.
笔者经过大量走访调研,结合伊斯兰教的基本信仰、对东北地区伊斯兰教建筑的装饰特征进行归纳总结,分析了装饰形式和装饰图案的样武特点,展现出东北地区伊斯兰教建筑的魅力,为当代伊斯兰教建筑的设计提供了创作素材. 相似文献
15.
Sixty sediment samples were collected from the main Songhua River in three years. Twelve polybrominated diphenyl ether ( PBDE) congeners ( BDE17, 28, 47, 66, 99, 100, 153, 154, 138, 183, and BDE?209) w... 相似文献
16.
以杭州瓶窑以上东苕溪流域为例,介绍了LLCHEN-A分布式水文模型参数的物理意义及确定方法.同时采用普适似然不确定估计(GLUE)方法,对模型参数的不确定性问题进行研究和分析.模型参数被分为不敏感参数和敏感参数,其中敏感参数又分为综合敏感参数、气象因子敏感参数及区域敏感参数.通过考虑模型参数与气象条件以及下垫面特征的匹配性,可以有效降低模型参数的不确定性,这将为今后流域水文模拟提供参考. 相似文献
17.
花色一直被认为是吸引传粉者的诱物之一,是开花植物与传粉者长期相互选择的结果。作者统计了东北地区虫媒植物共计1 142种,同时利用出版物和网络资料提供的照片并比对标准色谱,确定这些虫媒植物花的颜色和色谱范围。发现在东北地区,单色系花中白色花所占比例最大,超过35%,黄色系和红色系次之,各占20%多一点,橙色花最少,仅占2%,其余为混合色系花,即一朵花或一个花序上的花有两种以上颜色。针对色谱分类结果以及东北地区常见的传粉昆虫的相关资料,讨论了花的颜色与传粉者之间的相关性。 相似文献
18.
针对不可再生石油资源日益减少的问题,开发和利用天然生物材料替代短缺资源具有十分重要的意义。采用SEM、红外吸收光谱、XRD、荧光光谱等测试方法对东北地区生长的有翅蚜虫的自然巢穴(俗称小咬窝)材料进行了结构表征和光谱分析,发现该巢穴是一种新型自然生物石蜡。通过SEM分析确定该新型石蜡的结构为空心丝状物;红外吸收光谱表明该新型石蜡由饱和或不饱和的长链烃、长链脂肪醇、以及带有芳香烃及其衍生物构成;该新型石蜡XRD衍射图与标准PDF卡PDF#40-1995(正链烷烃,(CH2)x)匹配,并选用性质相似的工业蜡的XRD作对比进一步确定其性质,得出小咬窝原材料的主峰位置(21.694?,24.063?)和工业蜡的主峰位置(21.753?,24.076?)非常接近,可确定物相是相同的,从而确定小咬窝为一种天然生物蜡;对小咬窝原材料的发射光谱和激发光谱分析,获得发光波长范围为400~460nm,但发光强度非常微弱。 相似文献
19.
以东北地区的汉族、满族和朝鲜族的民居建筑为研究对象,具体探讨了地域环境、宗教文化和民族传统文化对东北民居建筑文化的影响. 相似文献
20.
利用HadISST OI海温和中国东北地区92站逐日气温资料,使用广义平衡反馈分析方法(GEFA)结合EOF分析方法(GEFA-EOF)研究了近50 a中国东北地区冬季气温对海表温度异常(SSTA)的响应.结果表明:对于热带和北半球中纬度5个海盆来说,东北地区冬季气温异常与同期热带大西洋和北大西洋海温异常有密切关系,与其他海盆关系不显著;热带大西洋的"正—负—正"三极型模态(TA3)以及北大西洋纬向上"正—负—正"三极型模态(NA3)分别对东北地区冬季气温的异常偏低和偏高有显著的强迫作用,且对北部地区的强迫作用大于南部地区.热带大西洋和北大西洋对东北地区冬季气温异常影响的可能途径为:热带大西洋TA3模态通过在北半球激发的"正—负—正"的遥相关波列,致使东亚大槽移至贝加尔湖地区,有利于极地冷空气南下至东北地区,导致该地区的冷冬;北大西洋的"正—负—正"三极型模态(NA3)直接响应使得东亚大槽减弱消失,极地冷空气南下受阻,导致该地区冬季气温异常偏高. 相似文献
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