短轮伐期日本落叶松家系生长性状遗传参数的变化

以湖北省建始县长岭岗林场 15年生日本落叶松自由授粉家系子代测定林为研究对象 ,研究纸浆材轮伐期内不同年龄阶段生长性状的家系间遗传变异、早 -晚相关关系及主要遗传参数随时间变化的趋势 ,确定早期选择年龄及早期选择因子。结果表明 :各年龄胸径、树高不仅在家系水平上存在着极显著的变异 ,家系内个体间也存在着丰富的变异 ,具有很大的遗传改良潜力 ,家系和家系内个体选择是日本落叶松改良的主体 ;性状的方差分量、遗传力、变异系数在树木生长过程中一直处于动态变化中 ,并表现出一定的规律性 ;胸径、树高的早 -晚相关十分紧密 ,且这种相关关系主要受遗传因素制约 ;对胸径和树高进行家系早期选择的最适年龄为 6年生 ,进行家系内个体选择年龄为 8年生 ,胸径作为早期选择指标较树高更能准确地表达成熟时的信息。     

洱海东岸面山石灰岩山地森林植被恢复与重建刍议

分析洱海东岸面山石灰岩山地的生境、植被条件和植被演替的一般规律，提出以封山育林为主，人工造林为辅的措施是本地森林植被恢复与重建的重要途径。     

Carbon and nitrogen dynamics under windrowed residues during the establishment phase of a second-rotation hoop pine plantation in subtropical Australia

The dynamics of carbon (C) and nitrogen (N), derived from the decomposition of windrowed harvest residues, was examined in the establishment phase of a second rotation (2R) hoop pine (Araucaria cunninghamii Aiton ex A. Cunn) plantation in subtropical Queensland, Australia. Following harvesting and site preparation, when residues were formed into windrows, in situ N mineralisation was measured in positions along the three tree-planting rows formed between the windrows. The position above the windrow had a higher nitrification rate than the other positions, averaging about 18 kg N ha⁻¹/month compared with 12 and 9 Kg N ha⁻¹ for the positions between and below the windrow positions, respectively. This position also had consistently greater soil moisture.

Macroplots were formed extending 5 m above and 10 m below a windrow. Windrowed residues within the macroplots were replaced by ¹⁵N-labelled material comprising hoop pine foliage, branch and stem. Hoop pine trees were planted within each macroplot with foliar samples taken at 12 and 24 months. Differences in foliar ¹⁵N enrichment between positions within macroplots were <1‰. Soil samples were taken from positions along the macroplots at 6-monthly intervals. Samples revealed an initial release of labile C and N but soil δ¹⁵N showed that residue-derived N was largely immobilised within the windrows for the 30-month sampling period. Whilst the use of windrows may act as a barrier to the down-slope movement of water, the residue N within the windrows may not be available to the trees of the following rotation for a considerable period following planting. Trees closest to the windrows may be able to introduce roots under the windrows thereby gaining access to the available N, but trees in the central tree planting row are unlikely to derive any significant benefit from the decomposition of windrowed residues.     

Large cardamom (Amomum subulatum Roxb.) plantation — An age old agroforestry system in Eastern Himalayas

Large cardamom (Amomum subulatum Roxb.) is a shade loving plant grown in the Indian hill states of Sikkim and Dargeeling district of West Bengal. About 30 important tree species are used to provide shade to the cardamom plants. Alnus nepalensis, a deciduous, nitrogen fixing and fast growing tree, is the species most commonly underplanted with cardamom. In addition to providing shade, it is also used for fuelwood. The old trees are cut and young plants coming up are allowed to grow in cyclic order. The quick decomposing leaf litter of A. nepalensis also fertilises the cardamom plants. The nitrogen added to the soil in this way has been found to be as high as 249 kg/ha. Large cardamom thrives well in a moist soil, which is maintained by water diverted from seasonal springs on the upper slopes. The system is well suited to conserving soil, water and tree cover of the characteristically steep slopes of the region. Moreover, the management inputs required for growing cardamom are low but the crop gives a higher financial return than rice or maize. The shade trees used in the system are also a major source of fuel, fodder and timber, especially as access to state owned forests is restricted by legislation. However, increasing incidence of viral chirkey and foorkey disease, panicle rot and capsule borer are reducing the cardamom productivity. It has been observed that integrating dairying and apiculture will further augment profitability from large cardamom agroforestry system.     

From Framework to Forest Activities: A Comparative Analysis of Different Ownership Types in Two Adjacent Regions

The paper examines the interactions between the demands of society, the restrictions due to recreational and protective functions of forests and the intensity and kind of forest management in the various ownership classes in Switzerland (CH) and Baden–Württemberg (BW) in south–west Germany. A survey was carried out among owners of communal forests, private forest landholders owning more than 200 ha of forest land and small-scale forest enterprises with up to 200 ha of forest land. The survey adopted a two-dimensional approach, using regions and comparable ownership classes in order to identify basic differences and underlying key drivers. It became obvious that there are relevant distinctions between the two countries. The paper highlights the present use of forests, the restrictions perceived by their owners, and the underlying management strategies in terms of structure of the forests, tree species composition and thinning activities. In BW the financial function is the dominant motivation for the majority of the private owners. The communities emphasize both timber and non-timber functions of their forests. Except for the protection function (avalanches, rockslides) the utilisation and importance of the forest in CH is lower than in BW. Profitability of forests continues to be a key-driver of intensity of forest management activities, but there is less influence on the choice of basic silvicultural strategies. The results of this comparative survey are placed in the context of a forest policy framework and the medium-term financial situation in the two countries.

关于征占用林地经济补偿办法合理性的探讨

本文以征用占用林地为例,列举出补偿应包括的主要内容,林地补偿与区域区位、补偿基数、补偿倍数等几个关键因素之间的关系等,提出了增加林地补偿合理性的一些思路。     

Effect of forest vegetation on runoff and sediment production in sloping lands of Loess area

According to fixed-position data for 1985–2003 from nine runoff plots of Caijiachuan watershed which lies in Jixian County of Shanxi Province in Loess area, this paper studied the relationship between vegetation and runoff and sediment production in sloping lands in detail, which helps to provide scientific basis for vegetation re-construction and studies on environmental transformation of water and sediment in watersheds of Loess area. Although, many study results testify that forest vegetation has an important function in soil and water conservation and cutting runoff, the effect of vegetation on runoff and sediment transmission is complicated, and this needs to be studied in depth. The results of the paper showed the following. Firstly, the natural secondary forest performs better function of soil and water conservation than artificial Robinia pseudoacacia forest, and runoff and sediment produced in the former in individual rainfall were 65%–82% and 23%–92% of those produced in the latter. At the same time, better correlative relationship between runoff and sediment production and rainfall and rainfall intensity were testified by multiple regression, but the correlation decreased gradually with the increase of canopy density of forest. Secondly, the difference of runoff and sediment production in several land use types was very distinct, and the amount of runoff and sediment produced from Ostryopsis davidiana forest and natural secondary forest were the least, and runoff and sediment produced from in artificial Robinia pseudoacacia forest and Pinus tabulaeformis forest were 5-fold as much as those from O. davidiana forest. Besides, runoff and sediment produced in mixed planting of apple trees and crops were 16.14-fold and 2.96-fold than those of O. davidiana forest, respectively, but the amount decreased obviously after high-standard soil preparation in the case of the former. Thirdly, based on gray cognate analyses of factors affecting runoff and sediment production in sloping land, the factors of stand canopy density and herb and litter biomass were the most significant ones, whose gray incidence degree exceeded 0.6. Therefore, mixed forest with multi-layer stand structure and shrub forest should be developed in vegetation re-construction of Loess area, which will help to increase coverage and litter thickness in order to cut down the runoff and sediment dramatically in sloping land. __________ Translated from Chinese Journal of Applied Ecology, 2005, 16(9): 1,613–1,617 [译自: 应用生态学报, 2005, 16(9): 1,613–1,617]     

巨桉优良无性系组培及区域试验

通过对巨桉11个优良无性系组培快繁研究,结果表明,巨桉外植体诱导以B1为基本培养基添加激素BA 0.4 mg.L-1和NAA 0.1～0.5 mg.L-1,诱导外植体最佳,诱导率可达79%以上;丛芽苗增殖调节培养基中激素浓度和基本培养中N、P、K、Ca、Mg、Fe的浓度配比使其芽体健壮,加快繁殖速度;生根培养以B2为基本培养基添加ABT 0.5 mg.L-1+IBA0.1～0.5 mg.L-1生根率可达80%以上;组培苗移栽基质选用泥炭土和竹炭肥,成活率达90%以上。区域试验表明:巨桉是较理想的速生耐寒桉树树种,可耐寒-4℃左右。     

祁连山森林土壤的水文生态效应

祁连山水源涵养林受立地水热条件的影响和自然、历史干扰,多世代演替共存,分布占祁连山3个垂直气候带,主要由湿性灌丛林、青海云杉林、祁连圆柏林、干性灌丛林4种类型组成,6个林型即湿性灌丛林、藓类青海云杉林、灌木青海云杉林、草类青海云杉林、祁连圆柏林、干性灌丛林。调查研究表明,各类森林枯落物(层)的现存量,组成成分、持水率、持水量等均不相同。森林土壤矿质层的主要物理性质因森林类型而不同,并均随着土壤的深度呈某种规律性的变异。森林土壤的持水量主要受土壤孔隙度的影响。在祁连山林区,森林土壤的持水量较非林地(牧坡草地)土壤为高,在各森林类型中青海云杉林和灌丛林的持水量,较祁连圆柏林为高。     

世界咖啡产销动态及海南咖啡产业发展对策

概述了1985～2006年世界咖啡的产销动态和引起价格大幅波动的主要原因;分析和讨论了在世界咖啡市场大背景下海南咖啡产业的发展现状及发展的对策。