期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
北京开花竹林土壤主要养分分析 被引量:1
1
作者 冯小虎 《世界竹藤通讯》 2017年第6期37-39,共3页
采用对比分析法,研究了北京市早园竹开花竹林和正常竹林土壤主要养分含量的差异。结果表明:开花竹林土壤中氮肥和磷肥含量明显低于正常竹林,钾肥含量没有明显差异;随着土壤深度增加,土壤中氮、磷、钾肥含量明显降低,尤其是竹鞭和竹根集... 采用对比分析法,研究了北京市早园竹开花竹林和正常竹林土壤主要养分含量的差异。结果表明:开花竹林土壤中氮肥和磷肥含量明显低于正常竹林,钾肥含量没有明显差异;随着土壤深度增加,土壤中氮、磷、钾肥含量明显降低,尤其是竹鞭和竹根集中分布的10~30 cm深的土层,土壤养分严重亏缺。因此,在竹林经营中,应以"补氮提磷"为土壤养分管理目标,同时将10~30 cm深的土层作为竹林施肥的"目标土层",积极探索有效的竹林施肥和土壤改良技术。 展开更多
关键词 早园竹 开花竹林 土壤养分 北京
下载PDF
竹林的更新
2
作者 周芳纯 《竹类研究》 1998年第1期162-164,共3页
关键词 老残竹林 开花竹林 竹材更新
下载PDF
An approach on the survivorship of giant panda in wild 被引量:1
3
作者 李兆华 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第1期59-62,共5页
The endangered giant panda (Ailuropoda melanoleuca) is endemic to th e mountains of Sichuan, Gansu and Shaanxi Provinces in China. The species had nu mbered over 2000 animals in early 1970s, but declined to no more th... The endangered giant panda (Ailuropoda melanoleuca) is endemic to th e mountains of Sichuan, Gansu and Shaanxi Provinces in China. The species had nu mbered over 2000 animals in early 1970s, but declined to no more than 1,000 anim als fragmented into perhaps 32 subpopulations in late 1990s as the result of num erous detrimental forces such as habitat shrinking, poaching and bamboo flowerin g. The mass flowering and followed die-off of bamboo played key roles in the dec lination of panda population in the past three decades. It trigged the starvatio n and following high mortality of giant pandas in 1970s over Min Mountains and i n 1980s across Qionglai Mountains in Sichuan Province. The situation of survivor ship is made worse by the fact that the panda habitat is fragmented into many sm all 'islands', each containing only a few pandas. Such small, isolated panda pop ulations are rendered even more vulnerable to extinction form threats such as ha bitat degradation, natural disaster, disease, and the deleterious effects of inb reeding. So restoring the panda habitat and reintroduction pandas to their histo rical habitat might be an important issue for protecting the giant panda in wild . 展开更多
关键词 Giant panda Population dynamics Bamboo flowering SURVIVORSHIP Cons ervation REINTRODUCTION
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部