权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Light energy gain and carbon balance of the seedlings of Quercus serrata in natural reproduction sites by the shelterwood method

防护林法自然繁殖地锯齿栎幼苗的光能增益和碳平衡

基本信息

批准号：
09660150
负责人：
HASHIMOTO Ryoji
金额：
$ 2.11万
依托单位：
Iwate University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09660150/
关键词：
konara oak natural reproduction seedlings photosynthesis stomatal conductance weeds and shrubs competition soil compaction 幹枝系周期伸長地本処理

项目摘要

Deciduous coppice forests dominated by Quercus serrata are widely distributed around cities and farm and mountain villages in Japan. Afforestation by conifers was actively made there during 1950's to 1970'. But recently the new trend towards natural reproduction by making full use of native broad-leaved tree species have been growing among people. The mother tree method and the shelterwood method have a number of advantages ; e.g. easily performed, enable to shorten the regeneration period and so on. Various fundamental studies and technical tests were carried out in order to examine applicability of these natural reproduction methods for Q.serrata. The canopy trees produced good seed crop almost every two years, bumper seed crop at intervals of 6 or 8 years. Larger number of mature seeds were supplied at years when the trees bore more seeds. Most of seeds fell right under tree crowns or near around them and collected mainly at low spots on the ground surface. The seed fall was followed by leaf fall and the leaves also collected in the same manner to cover seeds. So seeds could avoid desiccation damage. Seedlings showed , already at current year stage, high photosynthetic ability in leaves, 60 to 70 % of young trees, and the photoinhibition of photosynthesis was not observed. Daytime stomatal conductance of current year seedlings was kept relatively high even in non rain fall periods in summer, probably due to marked development of their root system. At the following year weeds and shrubs started to grow thick and suppressed certain parts of the seedlings. It appeared, however, that the regeneration of Q.serrata would succeed finally, if vigorous growth of bamboo grasses could be restricted artificially. Use of backhoe was extremely effective for removing under-ground system of bamboo grasses etc. Although soils were compacted by using such heavy machinery, the influence on photosynthetic performance and growth reaction of the seedlings was negligible.

以锯齿栎为主的落叶矮林广泛分布在日本的城市和农山村周围。 1950 年代至 1970 年代期间，这里积极开展针叶树造林活动。但近年来，充分利用本土阔叶树种进行自然繁殖的新趋势在人们中日益盛行。母树法和防护林法有许多优点；例如操作简便，能够缩短再生周期等。为了检验这些锯齿 Q.serrata 自然繁殖方法的适用性，进行了各种基础研究和技术测试。冠层树木几乎每两年就会结出丰收的种子，每隔六、八年就会结出丰收的种子。当树木结出更多种子时，会提供更多数量的成熟种子。大多数种子落在树冠下或树冠附近，主要收集在地表的低处。种子掉落后，叶子掉落，也以相同的方式收集叶子以覆盖种子。因此种子可以避免干燥损坏。幼苗在当年阶段已表现出较高的叶片光合作用能力，60%至70%的幼树没有观察到光合作用的光抑制。即使在夏季非雨季，当年幼苗的白天气孔导度也保持相对较高，这可能是由于其根系的显着发育所致。第二年，杂草和灌木开始茂密生长，抑制了幼苗的某些部分。然而，如果能够人为地限制竹草的旺盛生长，锯叶青竹的再生最终将会成功。使用反铲对于去除地下竹草等系统非常有效。尽管使用这种重型机械压实了土壤，但对幼苗光合性能和生长反应的影响可以忽略不计。