稀土在兴安盟林业发展中的应用研究

１９９１￣１９９４年，我们采用３００、５００、８００、１０００、１２００ｐｐｍ浓度的稀土溶液对华北落叶松，杨树苗木及苹果，葡萄树进行叶面喷施试验，其中分别以５００ｐｐｍ，８００ｐｐｍ的稀土溶液为最佳浓度，对苗高和地径及果树增产有明显促进作用，今后，应在兴安盟林业发展中广泛应用和推广。     

湿地松种子分级育苗的研究

湿地松湿系种子筛分为大、中、小三个粒度级进行发芽和播种育苗，据此进行的两地点两年度的试验结果表明，分级改变了种子的大小和重量分布，影响种子的发芽速度，进而影响到苗木的早期生长。在芽苗时期和苗木生长早期，各粒度级种子所育苗木有差异，但在生长后期已基本消失，混系种子分级未能达到改进苗木质量和一致性的目的，在育苗时首先要考虑种批的遗传构成，其次才是按种子大小或重量分级。     

广玉兰,白玉兰稀土育苗研究

对木兰科的广玉兰、白玉兰用稀土进行育苗对比试验，结果表明：１００～３００ｇ／ｍ＾３稀土溶液浸种１２ｈ，对广玉兰的出苗率、发芽率增效显著；出苗后，用１００ｇ／ｍ＾３的稀土结合施肥配合施用，能促进幼苗生长，各项指标均增长１７％以上。     

稀土在南洋楹育苗中应用试验

试验结果表明：南洋楹种子经沸水烫种后，再用稀土溶液浸种２４ｈ，可极显著促进种子快速整齐发芽；稀土配制南洋楹育苗基质育苗无明显效果；而采用稀土喷施的方法，可极显著促进苗木生长，提高苗木质量。     

湿地松芽移育苗

湿地松牙移育苗需一系列技术措施，除选择好圃地外，主要是： 一、种子催芽。选择籽粒饱满，生活力强，发芽率高的种子，于4月上旬浸种之前，先将种子漂洗，除去瘪粒和杂质，用多菌灵溶液浸泡种子，进行常规消毒。     

湿地松优良种子容器育苗试验

湿地松优良种子容器育苗试验,种子采用不同方式浸种,应用高锰酸钾和植物激素ABT3号生根粉溶液浸种育苗,用植物激素ABT3号生根粉溶液浸种的种子,比高锰酸钾溶液浸种的种子发芽率高6%,苗芽移苗成活率高4%,萌芽出土齐,苗木成活率高7%,苗木生长快,苗木地径粗3%,苗高2%.     

湿地松芽移育苗

湿地松芽移育苗需一系列技术措施,除选择好圃地外,主要是: 1.种子催芽选择籽粒饱满、生活力强、发芽率高的种子,于4月上旬浸种之前,先将种子漂洗,除去瘪粒和杂质,用多菌灵溶液浸泡种子,进行常规消毒.用45～60℃的温水浸种催芽,种子与水的比例为1:3.搅拌使种子受温均匀,浸泡1天后,把种子捞在箩筐里,置于适宜发芽的温度(18～25℃)下催芽.每天用干净温水(25～45℃)冲洗2次.切忌淋水温度低于催芽温度,以防种子感冒.种子的吸收水速度与温度有关,温度低,吸水慢,温度高,吸水快.     

湿地松容器育苗技术的推广应用

湿地松容器育苗技术研究结果表明,容器育苗比大田育苗优越：①1年4季均可育苗,幼苗出土快而整齐;②育苗周期短,从播种到出圃造林只需90～180d;③土地利用率高,是大田育苗的4倍;④1年4季均可造林,其成活率和年均高生长量比大田育苗的分别高12％和36．2cm,在立地条件差（特别是土壤瘠薄地段）的,其差异性更显著;⑤综合效益高,投入产出比为1:1．5。从1992年以来,共育容器苗297．4万株,推广造林1049．2hm2,占全县松类造林面积的97．2％。     

湿地松脱脂研究

对汨罗市桃林林场湿地松试样进行脱脂研究。选择适宜的化学试剂，并对反应浓度、温度、时间等工艺条件对脱脂的影响进行了探讨，通过正交设计实验，筛选出较好工艺条件为：浓度1％、温度120℃、时间3h。其脱脂效果良好，木材表面无溢脂现象，达到脱脂要求。     

Effects of clearcutting and site preparation on water yields from slash pine forests

Three operational-sized watersheds in poorly-drained pine flatwoods forests on sandy soils of the Lower Coastal Plain in north Florida were isolated and continuously monitored for more than 3 years. Recording flumes assessed quantity of runoff water. After 1 year of calibration monitoring, two of the watersheds were harvested, site-prepared, and planted under distinct harvest and regeneration practices.Minimum practices, imposed on one watershed, consisted of manual shortwood harvest of pinelands, roller drum chopping of harvest residues and residual understory, bedding, and planting. Maximum practices, imposed on another, consisted of tree length logging of pinelands with heavy equipment, extraction of lightwood stumps, burning and windrowing of logging residue and residual understory, harrowing, bedding, and planting.Both systems increased water yields. Following minimum practices, yield increased intermittently depending on weather. Following maximum practices the increase in water yield was quicker, larger, and more persistent over various seasons and weather conditions. In both cases water yields returned to preharvest levels or less within the year following planting.     

几种激素及稀土对牡丹幼苗生长的影响

用GA3、6-BAI、BA、芸苔素内酯、稀土等处理牡丹幼苗,结果表明:几种处理均有效影响牡丹幼苗的生长;对增强牡丹幼苗的叶绿素含量、硝酸还原酶活性和根系活力有积极作用;并在一定程度上提高牡丹幼苗的抗性。综合效果为GA3、稀土、芸苔素内酯对牡丹幼苗生长最有利,IBA、6-BA与前三者相比对牡丹幼苗生长影响较弱。     

Dry-matter partitioning in loblolly and slash pine: Effects of fertilization and irrigation

The effects of fertilization and irrigation, singly and in combination, on growth and dry-matter allocation in seedlings of Pinus taeda and P. elliottii were investigated under field conditions. Trickle irrigation was regulated to maintain soil water potential above −10 kPa and 111 g of fertilizer (N:P:K 10:10:10 plus micronutrients) were banded around each seedling on three occasions. Treatments were initiated at the beginning of the second growing-season in the field, the same year sampling was conducted. Sampling consisted of complete excavation of 15 seedlings per treatment per species beginning in early April and continued every 6 weeks through mid-November, 1986. Each seedling was measured for height, root-collar diameter, foliage, stem and root dry-matter, and total needle surface-area. Allometric growth-analysis was used to determine dry-matter partitioning among the various tree components.

The cultural treatments affected the two species differently. Loblolly pine responded to treatments by shifting dry-matter allocation from roots to shoots, with the greatest increase observed in the fertilization treatment. Slash pine showed a similar response to irrigation and to irrigation plus fertilization, but increased allocation to roots under the fertilization treatment. Allocation to stems was greater than to foliage in both species and treatments except the control loblolly pine.     

美国枫香苗木培育技术研究概述

从播种技术、土壤与苗木的关系、抚育措施及苗木质量评价等方面综述了美国枫香苗木培育技术的研究现状。可从中同枫香培育研究工作提供借鉴。     

刺龙牙播种育苗试验研究

2000年以来，作者对野生刺龙牙进行了人工栽培繁育的试验研究，收到了显著的效果。其种子发芽率与种子处理方法有密切关系。鲜种沙藏发芽率可达90％以上，干种不冷冻发芽率近于0。幼苗在不同光照下生长差异很大：在全光照下生长最佳，最高生长量可达30cm，弱光下苗木生长不良。     

Effects of compaction and water content on lodgepole pine seedling growth

Soil disturbance by heavy machinery usually causes a decrease in porosity and an increase in soil strength, which may limit access to nutrients and compromise seedling survival and growth. This study used a soil strength and a greenhouse experiment to assess the impact of compaction on lodgepole pine (Pinus contorta Dougl. Ex. Loud. var. latifolia Engelm.) seedling growth and the degree to which soil water influences the effects of compaction. A silt loam soil was collected from a forest landing in the central interior of British Columbia (BC) in the Sub-Boreal Spruce Biogeoclimatic zone. The silt loam soil was used in a soil strength experiment where soil with four water content levels (0.10, 0.18, 0.27, and 0.36 cm³ cm⁻³) was packed into 0.21 cm³ cores with three levels of compaction (74, 79, and 84% of maximum bulk density (MBD)). Soil strength was strongly affected by compaction and water content. In the greenhouse experiment, three water content levels (0.10–0.15, 0.20–0.30, and 0.30–0.35 cm³ cm⁻³) and three levels of compaction (67, 72, and 76% of MBD) were applied to soil in pots and 1-year old lodgepole pine seedlings were grown in the pots. Soil strength was highest (1275 kPa) for the high compaction and dry water content treatment in the greenhouse experiment. Though the soil strength for this treatment did not exceed 2500 kPa, the effect of compaction on growth was noticeable, with a decrease in diameter growth, total shoot mass, and new root mass as compaction increased at the dry water content. At dry water content and high compaction, foliar nutrient concentrations were greatest. Generally, water content had a greater impact on seedling growth than did compaction, at the levels of compaction used in this study. This study indicates that if there is a critical value for mechanical impedance of the conifer roots, it likely occurs below 2500 kPa. Our results are consistent with the explanation that soil strength incrementally affects root growth below 2500 kPa for this soil type. Expensive rehabilitation techniques may not be needed on lightly disturbed soils similar to that used in this study if soil water content is high enough throughout the conifer growing season to alleviate the effects of compaction on soil strength.     

Effects of nitrogen on leaf physiology and growth of different families of loblolly and slash pine

Leaf physiology and fractional dry weight allocation were examined in four open-pollinated families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Englm. var. elliottii) in response to growth under low and high N supply for six months. Nitrogen greatly influenced dry weight allocation, total mass, leaf net photosynthesis and leaf conductance in seedlings of both species. Family variation in fine root allocation was observed under low but not high N treatment, but for the majority of physiological and growth traits, family variation was stable under varying N treatment. Family rankings based on juvenile height, diameter and biomass accretion were similar to rankings based on field performance at 22 years in slash pine but not loblolly pine. Lower leaf maintenance respiration rates were associated with families exhibiting the most rapid juvenile growth.     

Loblolly pine and slash pine responses to acute aluminum and acid exposures

In response to concerns about aluminum and HCl exposure associated with rocket motor testing and launches, survival and growth of full-sib families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) were evaluated in a nursery bed experiment. Each species was exposed to a single soil application of aluminum chloride (0.33 M AlCl(3), pH 2.5), hydrochloric acid (0.39 M HCl, pH 0.6) or water, with or without mycorrhizal inoculation with Pisolithus tinctorius (Coker and Couch). After 20 weeks without inoculation, survival in AlCl(3) and HCl treatments averaged 52% for loblolly pine and 72% for slash pine. Inoculation improved survival of loblolly pine, receiving HCl from 49 to 73%, and of those receiving AlCl3, from 55 to 90%. Inoculation also resulted in improved survival and growth of individual families in AlCl(3), but not in HCl treatments. Results illustrate the relative resistance of both pine species to the acute treatments supplied, the improvement in resistance associated with mycorrhizal inoculation and the importance of field testing, following hydroponic screening, to verify the resistance to soil-supplied stresses.     

湖北湿地松纸浆林的定向培育技术

在对湖北省湿地松人工林调查和试验基础上，简要介绍了湿地松纸浆林定向培育的主要技术措施。内容包括选择光照条件良好、土层深厚、质地中等、排水良好的酸性土壤，经穴状整地，早春以I、Ⅱ级苗造林，造林初植密度为1000～3300侏/hm^2。为进一步推动湖北省短周期纸浆林的发展提供科学和实践依据。