ABT生根粉新剂型应用

三、造林1．杉木：用ABT7号生根粉25ppm浸根1小时,成活率968％。比对照提高3．9％,年高生长量提高23叽。2．湿地松：用ABT8号生根粉25ppm浸根1小时,成活率94％。3杜仲：用ABT6号生根粉50ppm浸根40分钟,成活率95．4％,比对照提高26．9％。经ABT处理的苗木造林1年后,生长量显著增加,平均高生长比对照增加4．scm。单株平均发枝数多22个枝条。4．枣树：用ABT6号生根粉50ppm浸根1／］＼时,成活率提高56％。根系平均增加19条,基径增加1．22cm,新消生长量增加匕．scm。5．侧柏：用ABTh号生根粉50ppm浸根40分钟。平均成活率达75％…     

1414杨嫩技扦插育苗试验

应用生根激素处理1414扬嫩枝扦插育苗试验表明．用ABTl号生根粉和a-NAA处理插穗，生根成活率均可达90％以上，比清水对照提高68．3个百步点，且ABTl号处理插穗较a-NAA处理提早3d萌发不定根；用ABT3号浸根后移栽成活率可达97％，比对照提高l9个百分点。     

ABT生根粉在黑荆树造林和种子处理上的应用研究

应用ABT3号生根粉进行黑荆树裸根苗造林和种子处理的田间试验和大区对比试验的结果表明,ABT生根粉能有效地提高黑荆树裸根苗的造林成活率11.1～25.2个百分点。对幼苗的高、径生长有较明显的促进作用,从提高成活率看,浸根法>浆根法>对照。浸根法最佳处理浓度是50～100ppm浸根2～4小时后造林,但用50ppm药泥浆沾根后造林,其操作方法简便;应用于黑荆树种子处理时,对促进发芽有一定的作用,但必须先用开水烫种法除去种皮胶质物后应用方见效果,适宜的使用浓度是3号ABT生根粉100ppm浸24小时。     

ABT生根粉在林木嫩枝扦插和苗木移栽应用的研究

应用1号ABT生根粉配制50PPm的浓度，对泡桐根、橡皮树穗条浸泡2个小时，生根成活率达95％；用1号ABT生根粉100ppm浸泡塔柏穗条2个小时，生根成活率达99％；用1号ABT生根粉150ppm浸泡桂花穗条2个小时，生根成活率达92％；用1号ABT生根粉300ppm浸泡绿竹枝条，成活率达78％；用1号ABT生根粉1500ppm速浸尾巨桉嫩枝，成活率达90％；用3号ABT生根粉50ppm处理香樟、天竺桂根系移栽，成活率达98％；用3号ABT生根粉100ppm处理火力楠根系移栽，成活率达90％，达到提高成活率，加速苗木生长的作用。     

ABT生根粉推广效果显著

1990年以来,ABT生根粉在我区的组织推广,有效地提高了苗木扦插生根率和造林成活率。据统计,ABT生根粉已普遍用于茶叶、桉树、杉木、油茶及各种名贵花卉的扦插繁殖,成活率达95％以上;用在某些难生根树种(如苦丁茶、雪松、良种桉、玉桂等)的扦插繁殖上成活率也达70％～92％,比不用生根粉的成活率高20个百分点以上,且生根提早,根多苗壮;在容器育苗中用于松幼苗上杯前处理苗根,成活率达98％以上,根系发达,苗健壮,抗逆性     

刺槐无性系营养钵及硬枝扦插育苗试验

为加速刺槐的良种化进程,用细根段刺槐根系和硬枝扦插进行育苗技术研究,提高良种繁殖率。用粗0．5 -0．8 cm的根段进行钵插育苗一般成活率可达85％以上,当年平均苗高和地径达2．5 m和2 cm以上,苗木出圃率达90％以上;利用ABT生根粉100 mg／kg进行硬枝扦插处理24 h效果最佳,扦插成活率、地径和苗高与对照相比分别高71．6％、28．9％和28．6％。     

南方红豆杉扦插育苗试验

采用ABT生根粉处理南方红豆杉插穗，对提高红豆杉插穗成活率，生根能力，扦插苗平均高，平均地径效果有为显著；南方红豆杉扦插繁殖用ABT生根粉处理是可行的，其成活率为43．6－77％，比用清水处理提高3．4倍至5．9倍。     

沙棘全光照喷雾嫩枝扦插育苗试验研究

生长季节,利用全光照喷雾育苗装置,在塑料容器中装入河沙∶锯末∶田土=5∶2∶3的混合基质,将插穗用质量分数为1.0×10-4的ABT3号生根粉溶液浸根1h或质量分数为5.0×10-5的溶液浸根2h后扦插,扦插深度6～8cm,能有效地提高沙棘嫩枝扦插苗生根率及成活率。     

雷竹侧枝育苗及造林技术试验

雷竹侧枝育苗及造林试验.应用ABT 2号生根粉不同浓度的溶液进行处理扦插育苗造林,与应用清水进行处理扦插育苗造林对照比较.发现应用ABT2号生根粉不同浓度的溶液处理的枝条繁殖的苗木比应用清水处理的枝条繁殖的苗木可缩短生根时间15 d,且根系生长旺盛,成活率可提高26%.次年出圃造林种植,母竹成活率能提高6%.第1年出笋率平均提高6%,第2年出笋率平均提高30%,第3年出笋率平均提高64%.     

华北落叶松造林技术

一、生根粉蘸根造林技术 华北落叶松造林应用生根粉浸根，可促进苗木根系伤口愈合和须根的生长．从而更好地提高造林成活率．增加苗木生物量生长，笔者对河北省塞罕坝机械林场千层板林场马蹄坑作业区以不同浓度的ABT生根粉3号处理2年生华北落叶松一级苗，蘸泥浆造林4年后，取得理想效果。     

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.