浅议工程量清单计价的造价管理

本文较详细地论述了工程量清单计价的意义、内容、合理性及可行性,并阐明其在实际运用中应注意的问题。     

双向链表人口迁移算法

最短路径搜索是路径分析中的热点问题.将双向链表和人口迁移算法的智能进化体制相结合,提出一种新的启发式智能仿生优化算法——双向链表人口迁移算法,并用于求解最短路径问题.仿真实验结果表明：双向链表人口迁移算法求解最短路径搜索问题是可行、有效的.     

甘肃叶蜂种类调查及分类研究 Ⅴ.松叶蜂科松叶蜂亚科和叶蜂科蕨叶蜂亚科、短叶蜂亚科、长背叶蜂亚科属种名录

整理采自甘肃膜翅目松叶蜂科松叶蜂亚科和叶蜂科蕨叶蜂亚科、短叶蜂亚科、长背叶蜂亚科标本总计102号,经鉴定分为13属20种。其中,新松叶蜂属1种、吉松叶蜂属2种、松叶蜂属1种、平缝叶蜂属5种、脊额叶蜂属1种、柄臀叶蜂属1种、凹颚叶蜂属2种、异颚叶蜂属1种、侧齿叶蜂属1种、长室叶蜂属1种、窗胸叶蜂属1种、长背叶蜂属2种、短唇叶蜂属1种。包括1甘肃新记录属:短唇叶蜂属,5科学新种:武氏吉松叶蜂、甘肃平缝叶蜂、黑胫平缝叶蜂、中华柄臀叶蜂、黑肩长背叶蜂,1科学新组合:白唇窗胸叶蜂和11甘肃新记录种和4已知种。     

盐池县青山乡沙生植物资源调查

采用样方调查和普查的方法,经过系统调查和统计,共采集标本94种,隶属29科,73属,其中有甘草、苍耳等药用植物36种,柠条、大针茅草等饲料植物29种,沙柳、小叶杨等用材树种17种,山苦菜、沙葱等食用植物16种.     

云南板栗害虫名录及主要种简述

在1978～1981年云南全省森林病虫害普查的基础上，1992～1995年又专门对全省的板栗病虫害进行了调查。经整理分析，云南板栗的害虫，分属6个目32个科计97种，本文按目分科记录了97种害虫的名称，为害部位和分布情况，并对其中5种主要害虫作了简述。     

竹类植物种质资源的收集及其利用研究

江苏省林业科学研究院竹类植物种质资源圃始建于20世纪70年代初期,至1989年底,共收集引进保存了4属26个竹种,保存圃面积0.667hm2。从2004~2006年,进一步扩建竹类植物种质资源圃,面积达4.0 hm2,现有竹类植物22属98种(含变种或变型),且竹种成活率、保存率较高。分别简要介绍了各个竹种主要用途及其配置方式与竹种选择,并提出了相关开发利用的建议。     

Conservation status of the world's hagfish species and the loss of phylogenetic diversity and ecosystem function

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The use of historical collections to estimate population trends: A case study using Swedish longhorn beetles (Coleoptera: Cerambycidae)

Long term data to estimate population trends among species are generally lacking. However, Natural History Collections (NHCs) can provide such information, but may suffer from biases due to varying sampling effort. To analyze population trends and range-abundance dynamics of Swedish longhorn beetles (Coleoptera: Cerambycidae), we used collections of 108 species stretching over 100 years. We controlled for varying sampling effort by using the total number of database records as a reference for non-red-listed species. Because the general frequency of red-listed species increased over time, a separate estimate of sampling effort was used for that group. We observed large interspecific variation in population changes, from declines of 60% to several hundred percent increases. Most species showed stable or increasing ranges, whereas few seemed to decline in range. Among increasing species, rare species seemed to expand their range more than common species did, but this pattern was not observed in declining species. Historically, rare species did not seem to be at larger risk of local extinction, and population declines were mostly due to lower population density and not loss of sub-populations. We also evaluated the species’ declines under IUCN red-list criterion A, and four currently not red-listed species meet the suggested threshold for Near Threatened (NT). The results also suggested that species’ declines may be overlooked if estimated only from changes in species range.     

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