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使用C#Builder和设计模式在.NET中管理Unmanaged程序代码
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作者 李维 《程序员》 2003年第9期76-81,共6页
本文将向读者展示在.NET 中如何对 Unmanaged 资源进行安全管理。
关键词 C#BUILDER 设计模式 unmanaged程序代码 程序员 程序设计 .NET 安全管理
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Deadwood position matters:Diversity and biomass of saproxylic beetles in a temperate beech forest
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作者 Vaclav Zumr Oto Nakladal +1 位作者 Josef Gallo JiríRemes 《Forest Ecosystems》 SCIE CSCD 2024年第1期120-130,共11页
Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red List.In addition to other management recommendations,there have been ... Deadwood plays a key role for biodiversity in forests.A significant number of beetles from this group are currently listed as endangered in the Red List.In addition to other management recommendations,there have been recent efforts to enrich stands with dead wood to promote biodiversity.An important parameter for forestry enterprises is the optimization of these interventions.The study investigated the abundance,species richness,gamma diversity,conservation value and biomass of saproxylic beetles in natural forests using window traps.A total of 89traps were used for saproxylic beetle monitoring,of which 29 were placed on lying logs,30 on snags and 30 as controls in forest stand space.A total of 35,011 beetles were recorded in 564 species(61 families).Notably,20,515 of these belong to saproxylic beetles(59%)in 311 species(55%),with 62 classified as Red-List species(20%).In the group of'all saproxylic beetles',the results indicate that a diversity and y diversity(q=0)remain consistent across various deadwood types,whileβdiversity showed significant differences.Significant differences were found in the Red-List species group,where a diversity and y diversity differed,with higher values observed in snags.Rarefaction based total species richness of site was estimated to be 391 species,including 74 Red-Listed species.Comparing the sample coverage of the studied stand categories showed that all saproxylic species exhibit a pronounced preference for inhabiting areas featuring lying logs.Conversely,Red-List species mainly inhabit snags,withβdiversity being more similar to snags and forest stand space.Notably,both the conservation value(weighted average by conservation status)and beetle biomass are significantly highest in snags,whereas stand space shows the lowest values across all measured saproxylic beetle indices.Furthermore,the use of traps set on the poles in forest stand space resulted in an underestimation of the actual stand richness by 20%-25%.Our results support the conclusion that snags are indispensable features in beech forests,playing a key role in promoting high species diversity,especially among Red-List species,and supporting the biomass of saproxylic beetles.Consequently,it becomes crucial to incorporate a higher percentage of standing deadwood in managed forests or actively create equivalent environments by introducing high stumps. 展开更多
关键词 SNAGS COLEOPTERA Fagus sylvatica unmanaged forests Red-list Coarse woody debris
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在.NET Framework中用C#开发MS Office应用程序
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作者 王胜春 王梓豪 林丹 《计算机与现代化》 2005年第5期109-110,115,共3页
基于Microsoft公司开发的.NETFramework平台,利用C#开发调用MSOffice组件的应用程序。
关键词 NET Framework C# OFFICE WORD unmanaged CODE managed CODE intemp
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The inventory of the carbon stocks in sub tropical forests of Pakistanfor reporting under Kyoto Protocol 被引量:5
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作者 Syed Moazzam Nizami 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第3期377-384,共8页
The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the... The United Nations Framework Convention on Climate Change (UNFCCC) requires reporting net carbon stock changes and anthropogenic greenhouse gas emissions, including those related to forests. This paper describes the status of carbon stocks in sub tropical forests of Pakistan. There are two major sub types in subtropical forests of Pakistan viz a viz Subtropical Chir Pine and Subtropical broadleaved forests. A network of sample plots was laid out in four selected site. Two sites were selected from sub tropical Chir Pine (Pinus roxburghii) forests and two from Subtropical broadleaved forests. Measurement and data acquisition protocols were developed specifically for the inventory car- ried out from 2005 to 2010. In total 261 plots (each of lha.) were established. Estimation of diameter, basal area, height, volume and biomass was carried out to estimate carbon stocks in each of the four carbon pools of above- and below-ground live biomass. Soil carbon stocks were also determined by doing soil sampling. In mature (-100 years old) pine forest stand at Ghoragali and Lehterar sites, a mean basal area of 30.38 and 26.11 m2.ha-1 represented mean volume of 243 and 197 m3·ha-1, respectively. The average biomass (t.ha-1) was 237 in Ghoragali site and 186 tha-1 in Lehterar site, which is equal to 128 and 100 t·ha-1 including soil C. However, on average basis both the forests have 114.5± 2.26 t.ha-1 of carbon stock which comprises of 92% in tree biomass and only 8% in the top soils. In mixed broadleaved evergreen forests a mean basal area (m2.ha-1)was 3.06 at Kherimurat with stem volume of 12.86 and 2.65 at Sohawa with stem volume of 11.40 m3.ha-1. The average upper and under storey biomass (t·ha-1) was 50.93 in Kherimurat site and 40.43 t.ha-1 in Sohawa site, which is equal to 31.18 and 24.36 t ·ha-1 including soil C stocks. This study provides a protocol monitoring biomass and carbon stocks and valuable baseline data for in Pakistan's managed and unmanaged sub-tropical forests. 展开更多
关键词 carbon stock models managed and unmanaged subtropical forests above and below ground biomass forest inventory and volume.
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Forest structure of a maple old-growth stand: a case study on the Apennines mountains(Southern Italy) 被引量:4
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作者 Pasquale A.MARZILIANO Vittoria COLETTA +3 位作者 Angelo SCUDERI Clemente SCALISE Giuliano MENGUZZATO Fabio LOMBARDI 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1329-1340,共12页
In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous enviro... In Europe, very small forest areas can be considered to be old-growth, and they are mainly located in Eastern Europe. The typical structures of old growth forests infrequently occur in Mediterranean mountainous environments, since they have been affected by human activities for centuries. This study focused on a remote and almost pure Italian maple stand located in southern Italy, which has not been managed for long time due to its inaccessibility. The effects of natural evolution on the forest stand were evaluated through the analysis of the spatial and chronological structure and the regeneration patterns, then estimating the amounts and quality of deadwood occurrence. Across the whole stand, all the trees with DBH (diameter at breast height) larger than 50 cm (LLT, large living trees) were measured (DBH and height) and age was also determined through a dendrochronological approach. The diameters observed ranged between 50 and 145 cm with ages of 12o to ~5o years. The Latham index calculated for trees within the sample plot highlighted a multilayered canopy with a dominant layer of largeliving trees (age 〉 120 years). The size-class distribution of stems had a reverse-J shape, and basal area was 52 m2 ha-1. Deadwood was exclusively constituted by standing dead trees and CWD and its volume was on average 31 m3 ha-1. Pure Italian maple forests are generally rare in Europe, and it was unexpected to find a forest stand characterized by a so complex structure with old growth attributes. The study of complex forest stand, even if small, could give precious information on the forest evolution, clarifying also diverse auto-ecological traits of tree species that usually are not common in our forests. 展开更多
关键词 Mediterranean mountainous ecosystems Natural evolution Stand characteristics DEADWOOD unmanaged forests
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