香椿两段式容器苗在喀斯特石漠化区域造林试验

为了检验香椿两段式容器苗在喀斯特石漠化区域造林的成活率、生长量表现情况。按试验设计,在贵州省金沙县马路乡犀牛村营造香椿容器苗示范林6.7hm2,作了与裸根苗造林的对照,对样方的成活株全面清点,求出成活率,用随机抽样抽取样株测量高生长量及径生长,对调查数据进行x2检验、T检验。结果表明,香椿两段式容器苗造林成活率、高生长量和径生长都显著优于裸根苗。为今后石漠化地区香椿造林开辟了新途径,亦是石漠化山区群众经济增长的一条捷径。     

竹文化景观表现形式研究

从园林建筑、园林楹联匾额、园林造景、园林雕塑和景观小品、园林设施5个方面探讨竹文化景观的表现形式,提出通过竹文化景观创建达到多样的园林景观效果,进而促进公园文化创意产业发展的建议。     

Spatio-temporal Variation of Distribution Patterns in Cunninghamia lanceolata Plantations

To aid in management of Cunninghamia lanceolata,the main timber species in Southern China,its variation of spatial distribution pattern was analyzed.Three permanent plots of C.lanceolata plantations with approximately the same site conditions,set by China continuous forest inventory in Shunchang,Fujian,were selected. C.lanceolata growth was divided into two stages: young trees(5 cm≤diameter at breast height (DBH)<10 cm) and mature trees(DBH≥10 cm). The DBH and coordinates of every tree(DBH≥5 cm) in the permanent plots were recorded in 2003 and 2008.The function L(r),improvement of Ripley’s K(r),the paircorrelation function g(r),and the uniform angle index(W_i) were used to analyze the spatio-temporal variation of spatial distribution patterns.The three permanent plots had mean uniform angle index(W) between 0.494-0.578 at low altitudes,0.465-0.477 at medium altitudes,and 0.426-0.601 at high altitudes.Results showed that altitude did not affect the spatial distribution pattern. The L(r ) and g(r) function curves of mature trees were generally lower than young trees’,i.e.tend to be more random or uniform distribution.So regardless of the initial distribution of young or mature trees,with the passage of time,there was a tendency for the aggregated distribution to change to a random distribution,and a random distribution to change to a uniform distribution.     

Research Advances in Effect of Nitrogen Deposition on Forest Carbon Sequestration

Nitrogen deposition imposes important impact on the function and the stability of forest carbon sequestration.This paper reviewed the research advances in the increasing response of forest carbon sequestration to nitiogen deposition, described the application prospects of stable carbon isotope technique in the research field.And finally this paper pointed out that,on the condition that nitrogen deposition rises,on the allocation of forest photosynthetic products and the change in soil carbon turnover rate are the two hotspots in the future carbon cycling research.     

普文热带树木园须弥红豆杉幼苗生长特征研究

在普文热带树木园开展了须弥红豆杉幼苗的露地栽培试验,通过连续观测及数据收集,分析了该试验点须弥红豆杉幼苗的各项生长指标的变化情况,发现须弥红豆杉幼苗适宜在低纬度、低海拔温暖湿润的环境下生长发育。     

三亚市林地资源保护与森林生态旅游开发的思考

通过分析三亚林业资源已开发现状及林业资源保护利用与发展森林生态旅游的关系,提出发展森林生态旅游的一些相应对策与措施。     

大兴安岭北部兴安落叶松天然林单木地上生物量

基于大兴安岭北部林区19块样地内104株天然兴安落叶松实测生物量数据,建立兴安落叶松天然林地上总量和分量相容性生物量模型,分别采用权函数和联立线性方程组消除方程的异方差和度量误差。结果表明：1)含度量误差的单木生物量相容性模型能解决总量生物量模型和分量生物量模型不兼容的问题,而且模型的预估精度高于经验模型;2)所建模型参数的决定系数 R2和模型偏差统计量,估计值的标准差 SEE、平均估计误差MPE、平均相对偏差 ME、平均相对偏差绝对值 MAE 分别为0.907～0.947,1.887～17.368,1.011%～2.703%,-4.937%～6.998%,5.408%～10.886%;3)对大兴安岭北部兴安落叶松天然林样木实测值进行统计分析,得到兴安落叶松天然林单木干材生物量占地上生物量的60.37%～76.80%,所占比例随年龄增加先增加再减小。树皮生物量占地上生物量的7.15%～20.11%,所占比例随年龄增加而减小;树枝生物量占地上生物量的8.51%～14.29%,所占比例随年龄增加基本呈现增加趋势;树叶生物量占地上生物量的5.12%～7.09%,在低林龄期时所占比例最大。     

热带兰花品种退化原因及防退措施探讨

兰花是兰科植物的总称,是开花植物中最大的家族之一。而热带兰花因花色艳丽、花期长等特点而深受消费者青睐。目前常有优良品种发生花朵变异及抗性减弱等现象,文章针对这一问题,就热带兰花优良品种退化的主要原因进行分析,有针对性的提出相应防治措施,以期为广大热带兰花生产者提供理论参考。     

集中供热工程投资估算中的Excel应用

应用Excel计算集中供热工程的投资估算。首先创建估算的模板,再应用模板来计算具体建设规模的投资估算,其应用过程简便、快捷、准确、科学。     

杭州城市古树名木的现状和保护措施

通过对杭州城市区范围现有古树名木的调查和分析,查明古树名木的生存现状和存在的主要问题,分析了原因,并提出了相应的保护措施。