湖北省柑橘林下种植模式探讨

对湖北省内柑橘林下种植模式及其技术要点进行探讨,认为林粮(油)、林药、林菌、林草、林菜等5种林下种植模式适合湖北省柑橘产区应用推广,对提高柑橘品质和产量、提高林地利用率和整体生态及经济效益大有裨益。     

发展林下经济新思路,打造林农增收新亮点——海南林菌间作模式与草料培育菌苗技术推广示范

正林下经济是在集体林权制度改革后,农民充分科学利用林地实现致富的新生事物。其投入少、见效快、易操作、潜力大。当前主要有林禽模式、林畜模式、林菜模式、林草模式、林菌模式、林药模式、林油模式、林粮模式等8种类型。"海南林菌间作模式与草料培育菌苗技术推广示范"项目,即利用林地树木郁闭后至采伐期,林下地面空闲时期套种食用菌等的一种生产模式。目前省林科所定安龙州试验基地建有蘑菇种苗培育、巨菌草加工厂、巨菌草种植与示范基地、橡胶园间作菌类模     

山地丘陵林农立体栽培经济效益分析

在山西省黎城县,对以核桃、花椒、君迁子为林冠的林药、林粮、林经等16种农林复合栽培模式前3年的经济效益进行了统计,并以净现值为指标进行了经济效益评价。结果表明,以花椒为林冠的复合类型投入成本较核桃和君迁子的低,且收入较其它2种的高;林药复合类型总体经济效益高于林粮和林经复合类型;林药复合类型中花椒—板蓝根复合栽培模式的经济效益最好,林粮复合类型中花椒—谷子复合栽培模式的经济效益最好,林经复合类型中核桃—辣椒复合栽培模式的经济效益最好。     

试论林农复合经营模式与技术

论述了林农复合的经营原则，从技术手段上，提出林粮、林菜、林药间作的方法。     

对我省淮北林业建设的几点思考

1历史的回顾 上世纪70-80年代,我国林业建设得到长足发展,尤其是地处黄淮平原的安徽淮北、河南、山东、江苏等省市发展之快最为突出。经过20年的努力,实现了大地园林化,形成农田林网化,林粮、林经、林药、林菜、庭院经济等多种林业发展模式,其生态效益、经济效益有了显著提高。当时颖上县的小张庄被评为全球500佳林业先进典型,     

辽西北地区林草及林药综合开发技术研究

林草、林药间作,林木为牧草和药材提供蔽阴条件,同时,林下间作牧草、药材,有利于改良林地土壤理化性质,增加肥力,促进林木生长。采取林草、林药间作的杨树,经精耕细作,与未采取林草、林药杨树对比,平均每年胸径增加了78.31%,高生长增加了186.58%。因此,在辽西北地区林草、林药间作是可推广的配置模式。奇可利、蒙古冰草、羊草是适于本地区种植的优良牧草;林间种植牧草、药材可获得较好经济效益。     

辽宁省林下经济发展现状与建议

文章概述了林下经济概念、特点和现实意义。结合辽宁省林下经济发展现状,将其划分为林下种植、林下养殖、林下产品采集和森林休闲观光4种类型,其中林下种植细分为林药、林菜、林菌、林果、林粮、林草6个模式;林下养殖细分为林蛙、林禽、林畜、林蜂、林蟹5个模式,指出辽宁省林下经济发展存在的问题,并提出了发展建议。     

山东省出台《关于加快林下经济发展的实施意见》

林下经济主要包括林菌、林药、林粮(油)、林草、林菜、林果、林苗、林花、林禽、林畜、特色养殖、森林景观利用和林下产品采集加工等。山东省是平原林业大省、人口大省,也是林业产业大省,林业产值截至2012年底达到4578亿元,居全国前列。林下经济代表着山东林业发展的新方向,它将农民想通过林地致富的渴求和社会对生态良好的需求,     

农林复合栽培模式构建研究

笔者选用林草、林药、林粮、林菜4种复合类型,通过采用覆盖保墒技术、界面根障技术,在平顺县阳高乡、黎城县李庄、榆次区什贴镇进行了农林复合模式栽培试验。从经济效益、生态效益、社会效益三方面分析了农林复合栽培模式在山西省部分地区林业生产中的作用,总结出该模式可以推广应用于山西省及周边立地条件相似的地区,应用前景广阔。     

强力推进三毛杨基地建设

近三年来,温县把三倍体毛白杨(以下简称三毛杨)基地建设作为中心工作来抓,高标准、高质量完成黄河滩区成片造林7万亩,植树700多万株,成活率达到95％以上。发展林草间作5000亩,林经、林药间作4万亩,林地围网养禽15万只。我们的主要做法是:     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.