沙地云杉胚性愈伤组织诱导

沙地云杉(Picea mongolica)是内蒙古特有的珍稀树种,种子生产受到大小年、倒春寒及重齿小蠹等虫害的严重影响,有性繁殖受到阻碍。本研究以沙地云杉成熟胚为外植体进行胚性愈伤组织诱导,对影响胚性愈伤组织诱导的调控因子进行了研究。结果表明:(1)沙地云杉成熟胚接于培养基中培养,5 d后子叶和胚根部位膨大,10 d后胚根均明显愈伤化,40 d后愈伤呈水渍状,60 d后愈伤呈白色丝状;胚性愈伤的发生始于非胚性愈伤的表面,且长成的胚性愈伤呈细胞核大、细胞排列紧密的特点;研究结果明确了沙地云杉胚性愈伤形态学和细胞学的变化过程。(2)确定了沙地云杉胚性愈伤组织诱导的最适培养基和最佳激素组合。胚性愈伤诱导培养基为LM,激素组合为2,4-D 6 mg/L、6-BA 2 mg/L和KT 0.5 mg/L最佳培养条件为暗培养,且胚性愈伤诱导率46%。沙地云杉胚性愈伤诱导的成功可为沙地云杉资源的保护、开发、利用提供了理论依据和技术保障。     

不同经营类型红松林对汤旺河流域土壤性质的影响

通过实地调查与试验分析，研究了汤旺河流域4种经营类型红松林对土壤性质的影响情况。结果表明：在研究地区无论土壤pH、土壤有机质，还是土壤养分和土壤物理性质，白桦与红松天然更新形成的混变林和白桦与红松人工造林形成的混交林都较红松人工纯林优越，维护林分土壤地力及涵养水分的功能强。而红松人工纯林较原始红松林和两种白桦红松混交林维护地力及涵养水分功能弱。研究结果为汤旺河流域森林恢复与重建提供了科学合理的途径。     

Functional diversity of microbial communities in the mixed boreal plain forest of central Canada

This study was designed to examine whether or not specific tree species (Picea glauca, Picea mariana, Pinus banksiana, Populus tremuloides), their post-fire stand age, or their position in a successional pathway had any significant effect on the functional diversity of associated soil microbial communities in a typical mixed boreal forest ecosystem (Duck Mountain Provincial Forest, Manitoba, Canada). Multivariate analyses designed to identify significant biotic and/or abiotic variables associated with patterns of organic substrate utilization (assessed using the BIOLOG™ System) revealed the overall similarity in substrate utilization by the soil microbial communities. The five clusters identified differed mainly by their substrate-utilization value rather than by specific substrate utilization. Variability in community functional diversity was not strongly associated to tree species or post-fire stand age; however, redundancy analysis indicated a stronger association between substrate utilization and successional pathway and soil pH. For example, microbial communities associated with the relatively high pH soils of the P. tremuloides-P. glauca successional pathway, exhibited a greater degree of substrate utilization than those associated with the P. banksiana-P. mariana successional pathway and more acidic soils. Differences in functional diversity specific to tree species were not observed and this may have reflected the mixed nature of the forest stands and of their heterogeneous forest floor. In a densely treed, mixed boreal forest ecosystem, great overlap in tree and understory species occur making it difficult to assign a definitive microbial community to any particular tree species. The presence of P. tremuloides in all stand types and post fire stand ages has probably contributed to the large amount of overlap in utilization profiles among soil samples.     

Microbial biomass and activity in soil and litter underPinus sylvestris, Picea abies andBetula pendula at originally similar field afforestation sites

Microbial biomass C and N, and activities related to C and N cycles, were compared in needle and leaf litter, and in the uppermost 10 cm of soil under the litter layer in Scots pine (Pinus sylvestris L.), Norway spruce (Picea abies L.) and silver birch (Betula pendula L.) stands, planted on originally similar field afforestation sites 23–24 years ago. The ground vegetation was differentiated under different tree species, consisting of grasses and herbs under birch and pine, and mosses or no vegetation with a thick layer of needles under spruce. The C:N ratio of the soils was 13–21 and the soil pH_{CaCl 2} 3.8–5.2. Both showed little variation under different tree species. Microbial biomass C and N, C mineralization, net ammonification, reduction) did not differ significantly in soil under different tree species either. Birch leaf litter had a higher pH_{CaCl 2} (5.9) than spruce and pine needle litter (pH 5.0 and 4.8, respectively). The C:N ratio of spruce needles was 30, and was considerably higher in pine needles (69) and birch leaves (54). Birch leaves tended to have the highest microbial biomass C and C mineralization. Spruce needles appeared to have the highest microbial biomass N and net formation of mineral N, whereas formation of mineral N in pine needles and birch leaves was negligible. Microbial biomass C and N were of the same order of magnitude in the soil and litter samples but C mineralization was tenfold higher in the litter samples.     

红松播种种子不同处理方法效果的研究

通过对红松种子进行3种不同方法的处理,在播种后,调查和分析不同处理方法对苗木生长情况的影响.结果表明,不同处理方法对苗木的发芽时间、出苗时间及出苗率影响较大;对苗木的高、径等性状指标的影响较大.3种方法中最好的是越冬埋藏法,其平均苗高4.4 cm,平均地径2.49 mm,生物量全干质量31.14 g.     

勃利县红松根朽病防治技术的研究

通过调查、观测,掌握了红松根朽病在勃利县林区发病规律以及环境因素对该病害的影响。结果表明,红松根朽病的发病规律为：郁闭度大的林分病害较重,阴坡重于阳坡,山中下腹重于山上腹;使用树干基部涂药和根部注药相结合的方法防治效果最好,防治效果达95%以上。     

干旱、半干旱地区异砧红松嫁接技术研究

试验分析了砧木选择、嫁接时间、嫁接方法等因子对干旱、半干旱地区异砧红松嫁接成活率和生长的影响。结果表明:樟子松、油松、赤松均可作为砧木嫁接红松。采用单芽接穗好于多芽接穗;适时早接有利于接穗木质化程度的提高;正交试验结果显示最佳处理组合为A1B1C1,即砧木为樟子松、4月中旬嫁接、芽端楔接法的组合,成活率达到90%以上。     

红松种子园经济效益分析

文章通过辽宁清河城红松种子园建设投资及生产效益调查,运用技术经济分析方法,对清河城红松种子园的费用、收益和经济效益进行了全面分析,结果表明,营建红松种子园经济效益巨大,每公顷种子园一个生产周期,可创利68965540.09元,是投资的160倍,投资收益率高达11.2%,1元投资可带来102.98元的直接收益。种子收益是营建红松种子园最直接的效益,可长期持续高效获得。     

黑龙江省东部山地红松人工林生态系统水化学特征

对黑龙江省东部山地红松人工林生态系统的大气降水、穿透水、树干径流、枯透水和地表径流中的pH值、溶解氧、浊度、总溶解固体、K、Na、Ca、Mg、Cu、Zn、Mn和Fe等水质指标进行了检测。结果表明:大气降水经过林冠层后,其水化学特征发生了明显变化,pH和DO降低,TURB和TDS明显增加,化学元素含量均不同程度增加。树干径流除了Cu外其余各化学元素含量均明显增加。穿透水和树干径流中各元素的变异系数较大。枯透水各化学元素的变异系数低于其他水样,只有Mn元素变化较大。穿透水、树干径流和枯透水中的K、Ca淋溶量较大,Cu、Zn淋溶量较少,根据淋溶系数的大小排列穿透水的淋溶序列为Mn>K>Mg>Cu>Fe>Ca>Na>Zn,树干径流的淋溶序列为Mn>Mg>K>Fe>Ca>Cu>Na>Zn,而枯透水的淋溶序列为Mg>Mn>K>Fe>Ca>Cu>Na>Zn。     

对黑龙江省森工林区全面保护培育红松等珍贵树种资源的探讨

黑龙江省森工林区是我国东北重要的生态功能区和后备森林资源储备基地,保护和培育红松等珍贵树种资源,恢复本地区森林植被顶级群落非常重要。本文从7个方面阐述了培育和保护红松等珍贵树种资源的实施方案。