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61.
62.
文章对整个公园植物空间布局情况以及公园内园林植物所形成的开敞空间、半开敞空间、覆盖空间和垂直空间4种景观空间的造景特点、植物构成进行分析。尝试摆脱以园林植物为审美主体的静态观赏模式,提出园林植物应从装饰性的栽植配角转变为景观空间营造的主角,即营造舒适自然环境和游憩境域,才能达到园林营建的真正目的。 相似文献
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64.
The assessment of information relating to the spatial patterns of individual trees is becoming an increasingly important aspect
of forest research and practical forestry. Numerous methods have been proposed over the years, with foresters preferring rapid
methods able to provide statistically confident information. The Mean of Angles is one of the simplest of these methods. It
is applicable for revealing complete spatial randomness (CSR) or the presence of clustering or regularity. We have tested
the potential of the arithmetic mean of angles to serve as a practical measure of the degree of regularity or clustering.
This study was conducted by applying random point sampling in various simulated theoretical point populations. The Mean of
Angles method deserves consideration as a practical option for examining the spatial patterns of trees in forests. We suggest
that the arithmetic mean of angles cannot be completely relied upon for indexing spatial patterns, but this deficiency can
be overcome by examining the frequency distributions of angular measurements. 相似文献
65.
论述中国山水画与古典园林的文化发展过程。通过分析先古时代、秦汉时期、魏晋南北朝、唐、宋、元明清时期六个典型阶段两者文化发展的社会原因和表象,总结出两者在各阶段的典型文化特征。 相似文献
66.
湖北省林下药材种类及种植模式探析 总被引:2,自引:0,他引:2
通过对湖北省地理气候特点、林药生产现状的分析,参考全省林下经济发展规划及道地药材生产区划,将林下药材种植划分为5个区域,并对其林下药材种植种类和模式进行总结和探讨.分析结果表明,鄂西南、鄂西北是湖北省发展林药种植的重点区域,鄂西三峡区及鄂东大别山区林药种植模式较为丰富,发展优势明显,鄂东南林药种植模式较为单一,有待进一步开发.各地在发展林药种植时,应综合考虑当地自然条件,药材生物学特性、市场需求及经济效益等因素,选择适宜的种植种类和种植模式,以减少林下中药材生产的盲目性. 相似文献
67.
以三峡截流纪念园景观设计项目为例,介绍其利用废旧材料进行景观设计的做法,对废旧材料的再利用不仅能表达废旧材料所代表的特定文化含义,更体现了一种循环经济思想。希望为大家解决工程废旧材料问题提供参考。 相似文献
68.
Robert E. Keane Paul F. Hessburg Peter B. Landres Fred J. Swanson 《Forest Ecology and Management》2009
This paper examines the past, present, and future use of the concept of historical range and variability (HRV) in land management. The history, central concepts, benefits, and limitations of HRV are presented along with a discussion on the value of HRV in a changing world with rapid climate warming, exotic species invasions, and increased land development. This paper is meant as a reference on the strengths and limitations of applying HRV in land management. Applications of the HRV concept have specific contexts, constraints, and conditions that are relevant to any application and are influential to the extent to which the concept is applied. These conditions notwithstanding, we suggest that the HRV concept offers an objective reference for many applications, and it still offers a comprehensive reference for the short-term and possible long-term management of our nation's landscapes until advances in technology and ecological research provide more suitable and viable approaches in theory and application. 相似文献
69.
To understand the influence of disturbance, age–class structure, and land use on landscape-level carbon (C) budgets during conversion of old-growth forests to managed forests, a spatially explicit, retrospective C budget from 1920 through 2005 was developed for the 2500 ha Oyster River area of Fluxnet-Canada's coastal BC Station. We used the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), an inventory-based model, to simulate forest C dynamics. A current (circa 1999) forest inventory for the area was compiled, then overlaid with digitized historic disturbance maps, a 1919 timber cruise map, and a series of historic orthophotographs to generate a GIS coverage of forest cover polygons with unique disturbance histories dating back to 1920. We used the combined data from the historic and current inventory and forest change data to first estimate initial ecosystem C stocks and then to simulate forest dynamics and C budgets for the 86-year period. In 1920, old-growth forest dominated the area and the long-term landscape-level net ecosystem C balance (net biome productivity, NBP) was a small sink (NBP 0.2 Mg C ha−1 year−1). From 1930 to 1945 fires, logging, and slash burning resulted in large losses of biomass C, emissions of C to the atmosphere, and transfers of C from biomass to detritus and wood products (NBP ranged from −3 to −56 Mg C ha−1 year−1). Live biomass C stocks slowly recovered following this period of high disturbance but the area remained a C source until the mid 1950s. From 1960 to 1987 disturbance was minimal and the area was a C sink (NBP ranged from 3 to 6 Mg C ha−1 year−1). As harvest of second-growth forest began in late 1980s, disturbances again dominated the area's C budget, partially offset by ongoing C uptake by biomass in recovering young forests such that the C balance varied from positive to negative depending upon the area disturbed that year (NBP from 6 to −15 Mg C ha−1 year−1). Despite their high productivity, the area's forests are not likely to attain C densities of the landscape prior to industrial logging because the stands will not reach pre-logging ages. Additional work is underway to examine the relative role historic climate variability has had on the landscape-level C budget. 相似文献
70.
以森林资源规划设计调查数据为数据源,定量分析毕棚沟风景区红叶彩林景观格局并运用能更加综合便捷地描述景观稳定性的主成分分析法构建研究区森林景观稳定性评价模型。研究表明:(1)风景区内主要红叶彩林景观类型有鲜卑花林、杜鹃林、四川落叶松林、高山柳林及忍冬林景观。(2)景观稳定性指标中最大斑块指数、斑块所占景观面积比例及斑块内聚力指数对研究区彩林景观类型稳定性影响程度较大。(3)鲜卑花林、杜鹃林、四川落叶松林及忍冬林的景观稳定性较高,花楸林、沙棘林、桦木林及杨树林的景观稳定性低。低稳定性景观类型宜采取改造低价值林分、抚育彩林、构建生态廊道等措施。研究为风景区森林旅游的可持续发展规划提供参考。 相似文献