关于推行营造林工程监理的探讨

营造林工程监理是规范和强化造林工程管理的客观要求,是提高营造林质量和成效的重要手段。文章在总结广东推行营造林工程监理成效的基础上,深入剖析了营造林工程监理中存在的主要问题,提出了进一步推行营造林工程监理的对策。     

沙地油松幼龄林造林试验及其生长状况研究

通过对沙地油松造林试验及其生长状况研究，结果显示：采取覆膜加土措施进行沙地油松栽植，能提高沙地油松的造林成活率。沙地油松在栽植9年以后，胸径平均每年增长0．60cm；高生长在前3年生长缓慢，5年以后树高以每年30-40cm的速度生长。油松主根系长仅为1m；水平侧根多且发达，主要分布在20-40cm深处。     

洞庭湖滩地造林成活率的关键影响因子

用样行法对洞庭湖滩地新造速生丰产纸浆林的成活率进行调查,同时了解造林地连续4 a汛期的水文规律和海拔高程的演变过程,通过分析造林成活率与主要影响因子之间的关系,发现淹水时间为滩地造林的限制性因子,营造速生丰产林、一般用材林和短周期工业原料林时,造林地年淹水天数依次不能超过19、35和62 d;苗木等级对造林成活率有重大影响,特级苗、Ⅰ级苗、Ⅱ级苗、Ⅲ级苗的平均成活率在海拔低于32 m的造林地上分别为68.8%、49.3%、18.7%、2.4%,在海拔超过32 m的造林地上分别为98.8%、79.6%、36.4%、14.7%;采用开沟抬垄整地可减轻涝渍胁迫,从而大幅度提高造林成活率.     

Effects of closing mountain for forest restoration in the watershed of Miyun reservoir,Beijing

The paper provides a systematical analysis of ecological restoration effects of natural secondary forest of closurearea in Chao Guanxi Gou, Miyun County, Beijing. The results indicate that through more than twenty years of hillclosing afforestation since 1983, canopy closure has improved almost by 0.2; forest cover rate has raised from 7.2% to 93.8%; biodiversity, tree biomass and vegetation community have increased to a great extent. Compared with the average canopy closure before hillclosing afforestation in this area, it has improved to over 0.4 in average and increased by 0.1-0.2. The forest coverage degree has reached more than 90%. Consequently, the forest plays more important roles in intercepting precipitation, improving water storage capacity of soil, decreasing the surface runoff, and preventing soil and water loss.     

太行山石灰岩山地油松人工林育林目标的确定

根据太行山中南地段油松人工林生长预测、投入产出分析、生态功能分析,提出了该区域油松人工林适宜培育以防护林为主的多育林目标,即以培育油松人工用材林、油松人工水源涵养林、油松人工水土保持林为育林目标,以发挥油松人工林三大效益为目的。     

浙江省针叶林下阔叶树直播造林试验

在马尾松林下进行南酸枣、毛红椿、山杜英、青冈、无患子、珊瑚朴、枫香、刨花楠、木荷直播造林试验,调查其发芽率、发芽势、树高与地径,结果表明:不同树种间直播发芽率存在显著差异,南酸枣、青冈、刨花楠比较适合直播造林,木荷、枫香、珊瑚朴直播造林效果不理想;在直播造林情况下,不同树种的树高、地径生长也存在极显著差异,树高生长以刨花楠和青冈较好,地径相对生长量以青冈和无患子效果较好。综合各种因素,青冈、刨花楠和无患子可以作为针叶林下阔叶树直播造林的树种选择。     

Establishment of Prosopis cineraria (L.) druce in the hot deserts of India

Prosopis cineraria (L.) Druce, commonly known as Jandi, is a deep rooted, nitrogen fixing, multipurpose tree endemic to the hot deserts of India. These trees are the essential component of the agroforestry land use system in these parts of India. The shade-intolerant tree reproduces poorly in nature and is difficult to propagate vegetatively. Germination up to 86.6% was observed after 15 days in seeds soaked in water at room temperature for 72 h. In another treatment, pouring of boiling water twice (at 0 and 6 h) over seeds and germinating after 12 h produced germination rates of 92.6%. Field establishment of containerized transplants in polythene bags (22×10 cm; 150 gauge) gave 90.3% survival after 6 months and 75.4% survival after 24 months. Seedlings were irrigated once during transplanting with 15 1 water. Bare root transplants and manual direct seeding after 6 months had a survival of 30.8 and 45.0%, respectively. Increased levels of nutrients (N, P and K), moisture content and organic carbon were observed under plantations as compared to open areas.     

模糊数学在适地适树决策方法中的应用

以小兴安岭带岭林区为研究对象,利用模糊数学原理,并通过对主要造林树种、立地类型及隶属度的确定,进行适地适树决策方法的探讨,得出各种立地条件下的适地适树方案.     

乡土植物在城市绿化中的应用

介绍乡土植物在城市绿地系统中应用的重要性,分析了乡土植物在城市绿地中的生态、景观、经济等方面的作用,认为人类生存必须依附于自然,城市的建设要尽最大可能减少对自然的破坏,增加乡土植物应用的比例,建立健康的生态系统。同时根据植物景观的需要,介绍了部分在城市绿地有应用前景的野生植物类型。     

封山育林是恢复和重建晋西黄土高原森林植被的重要途径

论述了晋西黄土高原封山育林的必要性、理论依据及可行性。分析了不同时期弃耕地和封禁小流域的植物演替和植被恢复规律。在黄土弃耕地上植物群落演替规律为：弃耕后,15a-20a为草本植物群落阶段;21a-25a可形成灌木群落;26a-30a能达到较成熟、稳定的灌丛群落;30年后,开始形成乔木林。黄土残塬沟壑区封禁小流域植被恢复情况为：经过12a,木本植物的种类达到了41种,分属于16科34属,其种源来源于周围残存的次生林。总结了封山育林的效果。