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兴安落叶松种源区划及优良种源选择 总被引：2，自引：0，他引：2
对兴安落叶松17个种源的树高、胸径和材积等生长性状进行方差分析的结果表明：种源间差异显著或极显著，并通过相关分析研究了兴安落叶松地理变异规律。兴安落叶松的生长性状主要受3个因子的影响。经度和海拔为主，纬度为辅，呈现出水平和垂直双向连续渐变的特点。对生长性状和各种源的地理位置进行聚类分析，划分为3个种源区：大兴安岭南、西、北部种源区；小兴安岭北部、大兴安岭东部种源区；小兴安岭东南部种源区。对各种源的生长性状进行了多重比较，选出乌伊岭和友好种源为帽儿山及其毗邻地区的最佳种源。 相似文献
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木麻黄树种及种源试验研究 总被引：2，自引：0，他引：2
对木麻黄科6个树种在广东饶平进行引种试验,结果表明：6种木麻黄胸径、树高、通直度、保存率等性状存在着极显著差异,并具较高的遗传力。由方差分析及多重比较可知,滨海木麻黄、肥木木麻黄、休格尔木麻黄表现较差,生长缓慢、干形差、保存率也低于50%;粗枝木麻黄表现中等;细枝木麻黄、山神木麻黄及对照（短枝木麻黄）生长较好,适应性较强,适宜在广东沿海地区利用和发展。对细枝木麻黄8个种源、粗枝木麻黄9个种源进一步分析对比,结果表明：细枝木麻黄种源间性状差异极显著,且遗传变异系数较大,遗传力较高,选择潜力大,其中15574、13521种源表现最佳,并能获得较高的遗传增益,而13508、15601种源表现较差;粗枝木麻黄种源在树高、胸径2个指标上存在极显著差异,遗传力较高,但在通直度与保存率指标上差异不显著,遗传力较低,其中15938、15941种源表现较好,具有较高的遗传增益,其余种源表现一般。 相似文献
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班克松地理种源试验初报 总被引：1，自引：0，他引：1
本项研究在北美引种了２４个种源的班克松种子，二年苗期试验结果；班克松不同种源在苗期生长、抗性、针叶、种子千粒重等性状表现出极明显的遗传分化；揭示出生长性状随纬度、经度而递减的渐变模式；初步选择出１４＃、１６＃、１１＃为吉林省中、东部造林最佳种源，其高生长量分别超出吉林省大面积推广造林的０９＃（美国密执安州）种源的１４．７％、１３．７％、１０．６％；通过多性状的ＰＣＡ分析，将班克松原产地（北美）划分出４个种源区，其中１号种源区为吉林省引种最佳种源区。 相似文献
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为了解樟树遗传变异的来源和规律,进行了樟树苗期种源／家系两水平试验研究。结果表明,樟树的遗传变异存在于种源和家系两个层次。樟树苗高、枝下高、冻害性状在种源层次的变异远大于家系层次的变异,地径则相反。方差分析表明,樟树苗期种源间在苗高、地径、枝下高、冻害性状上有极显著差异;家系之间在苗高、地径、冻害性状上有极显著差异,在枝下高性状上无显著差异,种源内大多数家系间各性状的差异达不到显著水平。苗高、枝下高、冻害各性状值,高于富阳种源（Ｃｋ）的家系分别有１２５、９５、８８、１０８个,低于富阳种源（Ｃｋ）的分别有５６、８６、９３、７３个。苗高与种源纬度显著负相关,与年均温、１月均温、绝对低温显著相关;冻害与纬度极显著负相关,与年均温、１月均温、绝对低温显著相关;枝下高与纬度显著相关,与年均温、１月均温、绝对低温显著负相关;苗高与冻害极显著相关,与地径显著相关。 相似文献
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尾叶桉与细叶桉8个种源生长性状与保存率的差异和遗传分析结果表明；种源间除高径比外各性状的差异极显著，种源层次各性状遗传力为43.25％～88.14％，单株层次各性状遗传力为16．00％～65．01％；树高、胸径、材积等生长性状间呈紧密的正相关，保存率与生长性状的相关不显著。3、5年生时尾叶桉14532种源和细叶桉13541种源在各自的树种中生长最优，平均单株材积分别这0.09636m^2时0.04516m^3。经综合评价，细叶桉13541、13544和尾叶桉14532、14531为优良种源。估算了参试种源各个性状的育种值。 相似文献
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桉树人工林的社会、经济和生态问题 总被引：29，自引：2，他引：27
按树具有很好的社会和经济效益。按树人工林不但提供各类木材和非木材产品,而且对农田风沙防护、园林绿化以及水土保持等也有重要作用。但长期以来,对按树人工林的生态问题存在很多争论,本文就此作了详细的论述。 相似文献
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Yuka Onozawa Masaaki Chiwa Hikaru Komatsu Kyoichi Otsuki 《Journal of Forest Research》2009,14(2):111-116
In recent years, moso bamboo (Phyllostachys pubescens) forest areas in Japan have rapidly expanded, and bamboo is now invading nearby natural or plantation forests. To date, only
one study has examined the rainfall interception of a moso bamboo forest. In that study, it was reported that the interception
ratio (interception/rainfall) of the bamboo forest did not exceed the interception ratios of other natural and plantation
forests (n = 4) in Japan. To expand the current state of knowledge about rainfall interception of bamboo forests, we measured throughfall
and stemflow at another bamboo forest site. Annual rainfall (Rf), throughfall (Tf), and stemflow (Sf) during the measurement period were 2,105, 1,556, and 322 mm, respectively. Annual rainfall interception at the plot (I) was 228 mm. Tf/Rf, Sf/Rf, and I/Rf were 73.9, 15.3, 10.8%, respectively. I/Rf was less than 20% throughout the year except in October, the month with lowest rainfall. We also summarized rainfall interception
data from 19 other natural and plantation forests. The I/Rf value of our site did not exceed the I/Rf values of these natural and plantation forests (n = 19). Our data will be useful for assessing changes in water resources that result from replacement of natural or plantation
forests by bamboo forests. 相似文献
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Bird species diversity and bird species richness were surveyed in a natural mixed forest (mature forest) and in a coniferous
plantation (30–40 years old) monthly from 1990 to 1994. These forests were 20 km apart and had similar weather conditions
and soil types. There were larch and cedar plantations, and hardwoods along streams in the coniferous plantation. In the natural
mixed forest, 55 bird species were found, whereas 40 species were recorded in the coniferous plantation. The species diversity
of bird communities was significantly higher in the natural mixed forest than in the coniferous plantation mixed with hardwood
trees. This result indicates that the coniferous plantation mixed with hardwood trees, presumed to be a more simplified environment,
is likely to be less inhabitable for many bird species than the natural mixed forest, suggesting a relationship between the
diversity of the forest environment and the diversity of the bird community. A higher number of bird species was recorded
in the small coniferous forest mixed with hardwood trees compared with those in the coniferous plantation. The mixing of broad-leaved
trees in a coniferous plantation was suggested to be effective in increasing number of bird species. These tendencies were
recorded all through the year during our study. In snow-covering periods, both the diversity and the bird species richness
fell in all study sites every year. Snow cover would have greater effect on bird species diversity in the coniferous plantation
than in other forest types probably due to diet shortages caused by the snow cover over the forest floor. 相似文献
15.
Reclaiming sodic soils for wheat production by Prosopis juliflora (Swartz) DC afforestation in India
A green house pot trial was conducted to assess the impact of Prosopis afforestation on the productivity and fertility of degraded sodic soils in Haryana, India. Wheat (Triticum aestivum, L; cultivar HD 2329) plants were grown from seed on top soils collected from a chronosequence of 0, 5, 7, and 30-year-old Prosopis juliflora plantations established on highly sodic soils and a non-sodic reference soil collected from a local farm. The afforestation improved physical and chemical properties of surface soils by decreasing pH, electrical conductivity and exchangeable Na levels, and increasing infiltration capacity, organic C, total N, available P, and exchangeable Ca, Mg, and, K levels. The amelioration effect of the trees on top soil increased with duration of tree occupancy. Soil nutrient status under the 30-year-old plantation was higher than that of the non-sodic farm soil. The reduced soil sodicity and improved fertility contributed to higher germination, survival, growth, and grain yield of wheat plants grown on the Prosopis chronosequence soils, even surpassing the yield attained on the farm soil in the case of 30-year-old plantation soil. Sodium accumulation in the crop declined while N, P, K, Ca, and Mg uptake increased with soil plantation age reflecting the changing nutrient status of the rooting zone due to afforestation. Results confirmed that successful tree plantation may restore the productivity and fertility of highly degraded sodic soils. 相似文献
16.
Diosdado A. Paler Takeo Shinohara Romulo A. del Castillo Isamu Nomura 《Journal of Forest Research》1998,3(4):193-197
The study describes the development of industrial tree plantation in a specific region in the Philippines. Two case studies
using plantation companies are presented. Likewise, management prospects and problems are considered. Since industrial plantations
are given emphasis in the 1980’s, plantation owners are already capable to engage in development. Although majority are small
scale, their management performance is considerable. Likewise, social and economic gains are enormous. Fast growing species
for pulpwood are developed under different climatic conditions at low stocking density. However, further development is limited
by problems particularly product development, financial assistance, and the volatility of plantation policy. Several approaches
are endorsed.
The study is partially funded by the Sasagawa Research Foundation of the Japan Science Society. Sincere appreciation is extended. 相似文献
17.
福建省人工用材林收益与风险分析 总被引：2，自引：0，他引：2
对福建省人工用材林的投资风险进行实证分析,得出结论:1993-2002年,福建省人工用材林自然灾害风险所造成的平均风险损失较低,这与木材税费下降和人工林优惠政策出台有关;然而,对私人而言,其森林一旦发生火灾或病虫害,将造成投资损失,因此,政府必须建立分散风险的制度. 相似文献
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Oil palm plantations have been touted as one of the main drivers of deforestation in Indonesia. This paper aims to explain how oil palm companies accumulate power that enables them to control forestland and convert it into oil palm. Specifically, this paper identifies empirical evidence pointing to why oil palm companies emerge as powerful actors in land use conflicts. This paper uses the case of forest lands claimed by different actors – i.e. a timber plantation company, an oil palm company, and local communities – in West Kalimantan, Indonesia. Before the decentralisation policy, the interests of timber plantations were principally safeguarded by coercion from the forest ministry. The timber company was also supported by local communities by promising financial incentives to them. Following the decentralisation policy, additional actors get involved in the land use conflicts leading to more complex power interplays. In fact, some forestlands licensed for timber plantations are used by the oil palm company. Oil palm interests resonate with the economic interests of local governments, who use their legal mandates on land use allocation to facilitate the establishment of oil palm. The power of the oil palm company is also enhanced by the support from local communities, to which it handed more financial incentives than those of the timber plantation. It also used dominant information of customary claims and land appropriation by the ministry of forestry, with which it persuades local communities to pressurize government institutions to support oil palm operations. 相似文献
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Increases in stand volume with some currently introduced provenances of Acacia mangium: Papua New Guinea (PNG) and Far North Queensland (FNQ), were projected based on their superiorities in 3-year height growth
in seedling seed orchards using the growth model developed for unthinned plantation for pulp and paper production in South
Sumatra, Indonesia. The height growth of these provenances was better than that of the local selections from Subanjeriji by
10%–15% at 3 years old and these percentage superiorities would be expected to remain at around 9%–14% until the 8-year rotation.
This amount of increase would result in a 7%–10% increase in basal area and hence it would produce a 17%–26% increase in stand
volume at rotation age when compared with the Subanjeriji seed source that was being widely used for the plantation establishment
of A. mangium in Indonesia.
Received: July 24, 2002 / Accepted: December 3, 2002
Acknowledgments The authors thank Mr. Hardjono, the director of plantation establishment at PT Musi Hutan Persada for his permission to use
data of permanent plots for the growth modeling of A. mangium. The authors are grateful to the staff at PT Musi Hutan Persada, Research and Development Center for Biotechnology and Forest
Tree Improvement, Japan International Cooperation Agency for their implementations of the study. Our thanks are also due to
Dr. Yoshida, associate professor at Kyushu University, for his advice on developing the growth modeling work.
Correspondence to:S. Kurinobu 相似文献
20.
Yuichi Yamaura Hitoshi Tojo Yasumasa Hirata Kenichi Ozaki 《Journal of Forest Research》2007,12(4):298-305
It is important to conserve forest-dependent organisms not only in broadleaved forests but also in plantation forests. We
examined how surrounding forest areas affect forest bird assemblages inhabiting conifer plantations and broadleaved forests
in a rural landscape in central Japan. Surrounding forest areas were measured separately as plantation area and broadleaved
forest area within 200 m of each sampling site. We used hierarchical partitioning to analyze the effects of surrounding forest
areas and stand structures (stand height and understory coverage) on the occurrence of four species groups. We especially
focused on mature forest users that are most sensitive to loss of broadleaved forests. Occurrence of mature forest users inhabiting
plantation sites was positively affected both by plantation area and broadleaved forest area whereas the occurrence of mature
forest users inhabiting broadleaved forests was affected by stand height only. These results suggest that surrounding forest
areas were more important to mature forest users in plantations than in broadleaved forests. To conserve mature forest users,
increasing surrounding forest areas are important in plantations whereas increasing stand heights would be effective in broadleaved
forests. 相似文献