大兴安岭兴安落叶松林倒木分解速率及其养分含量研究

以内蒙古根河市大兴安岭生态站为研究地,以大兴安岭兴安落叶松原始林为参照对象,对皆伐林、渐伐林2种采伐管理类型进行对比研究,对兴安落叶松和白桦的倒木分解及其养分含量进行了研究。结果表明:兴安落叶松倒木的分解常数是0.0121/a(R2=0.9715),白桦为0.2859/a(R2=0.8915)。兴安落叶松和白桦倒木中有机碳含量随着倒木腐朽等级的增加而减少,全N含量随着倒木腐朽等级的增加而增加,全P含量随着倒木腐朽等级的增加而增加,全K含量随着倒木腐朽等级的增加而不改变,没有规律性。随着采伐干扰的逐步加强,倒木中有机碳含量、全N、全K和全P含量在逐步减少。     

仔猪采暖保温设备的研究：Ⅱ.初生仔猪红外线采暖设备的比较

本试验比较了石英管灯、红外线灯辐照下的辐射热、空气温度、动物模型产热量与散热量以及10、20、30、60日龄仔猪体重。结果悬挂高度为40和50cm时,二者辐照下的气温无显著差异,在高度为50cm时,辐射热量差异也不显著,但40cm时,石英管灯的辐射热量大于红外线灯的。二者辐照下的动物模型产热量与散热量均无显若差异。动物试验表明,仔猪各日龄体重二种灯间差异不显著。石英管灯可代替红外线灯作为仔猪的采暖设备。     

小径原木真空干燥机加热系统的理论设计

以径级为10cm、含水率从50%干至10%的桉树小径原木为标准材,笔者通过对小径原木真空干燥过程中热平衡的分析及计算,完成了装载量为2.0m3的小径原木真空干燥机加热系统的理论设计.其设计计算结果可为干燥机内部设备的选型,小径原木真空干燥基准及工艺的制定,以及为此类木材真空干燥设备的设计与开发提供一定的理论参考.     

Wood-decaying fungi in the forest: conservation needs and management options

Wood-decaying fungi are essential for the functioning of forest ecosystems. They provide habitat for many other organisms and enable the regeneration of forests throughout the world. Since wood decomposition is a decisive process in nutrient recycling, soil formation and the carbon budget of forest ecosystems, it is receiving increasing attention from forest ecologists, pathologists and managers. Research has focussed on the factors driving the species-richness of wood-decomposing organisms and is moving on to analyse the effects of this species-richness on ecosystem functioning. Coarse woody debris (CWD) and its associated wood-decaying organisms have been drastically reduced in abundance and diversity by forestry and so these features often have potential as conservation indicators. Protective measures at a landscape level are needed for threatened wood-inhabiting fungi. These include restricting salvage operations in windthrow stands, actively encouraging the accumulation of deadwood in forests, and facilitating decay in standing trees by inoculating them with fungi. Here, we aim to collect and summarize recently produced work on deadwood ecology, pointing out research gaps and perspectives.     

不同时间尺度上西藏色季拉山急尖长苞冷杉林下倒木空间格局分析

【目的】分析西藏色季拉山急尖长苞冷杉(Abies georgei var.smithii)原始林下倒木在不同时间尺度上的空间分布格局及其相关性,探讨该森林生态系统内倒木的分布规律。【方法】在研究区内设置100 m×100 m固定样地,采用相邻网格法对样地内倒木进行调查,获取倒木的大小头直径、长度、腐烂程度、植被覆盖状况、坐标等基本信息,用腐烂等级表征倒木的时间尺度,分析倒木在不同时间尺度上的空间分布格局。【结果】倒木总体空间分布格局随空间尺度的增大依次呈现集群分布、随机分布和均匀分布,且以随机分布为主要特征;在各个时间尺度上的倒木均呈现显著的集群分布;不同时间尺度上的倒木在空间分布上虽无显著关联,但时间尺度间隔越近,越趋于正关联,越远则越趋于负关联。【结论】色季拉山急尖长苞冷杉原始林下倒木在空间分布上具有明显的时间特征,这与当地异常气候密切相关。     

天山云杉倒木的持水特性

倒木在森林生态系统尤其是山地森林生态系统的水文功能和水土保育功能等方面具有重要的作用。为了解天山云杉（Picea schrenkiana var. tianschanica）倒木的持水特性和其对天山林区水文功能的影响,沿天山山脉由西至东选取跨越9个经度的5个地区（昭苏、新源、呼图壁、天池和奇台）分别进行取样,运用浸泡模拟法测定天山云杉倒木的吸水过程和持水能力。结果表明：① 天山云杉倒木的吸水过程在5个地区随着浸泡时间的推移,其持水量、持水率和持水能力均随着腐解等级的升高而增加。在浸泡吸水过程中天山云杉倒木的持水量(Q)随着浸泡时间(t)的增加而增加,两者的关系可用Q=aln t+b来拟合。② 浸泡过程中天山云杉倒木吸水速率(V)随着浸泡时间(t)的增加而呈下降的趋势,两者的关系可用V=c t^-d来拟合。③ 天山云杉倒木持水能力(Q′)与腐解等级(x)的关系可用方程Q′=ex²+fx+g来拟合。天山林区5个地区的天山云杉倒木的持水特性存在明显的差异,该成果为进一步开展天山林区水文功能性研究奠定了基础。     

原木端面图像检尺直径识别的一种算法

论述了应用计算机图像处理和识别技术来识别不规则圆形类目标的问题,以成捆原木端面图像为实例,提出一种原木端面检尺直径识别的算法。     

接种穴深度与香菇产量关系的研究

黑龙江森林资源极为丰富,树梢枝丫是栽培香菇的极好的原木,所以段木是食用菌的宝贵资源,然而怎样充分利用段木内所含养分,缩小实际栽培量与理论产量间的差距,黑龙江段木接种穴的深度与香菇产量是否有关?这类的报道尚不多,本文着重对穴深与产量间的关系作了初步探讨。     

具有图像处理功能的原木X射线检测系统

选择 X 射线作为检测源透射原木,根据检测透过被检物体后的射线强度差异,判断被检测原木内部是否存在缺陷和检测缺陷细节。检测过程中应用计算机数字图像处理技术对原始的 X 射线图像进行中值滤波、图像增强、差分和边缘检测,使得处理后的图像更加清晰,图像中的目标易于人眼识别。实验结果表明这种方法行之有效。     

Season and substrate effects on the first-year establishment of current-year seedlings of major conifer species in an old-growth subalpine forest in central Japan

Seasonal and substrate effects on first-year seedling establishment of major conifer species (Abies mariesii, Abies veitchii, Picea jezoensis var. hondoensis, and Tsuga diversifolia) were assessed in an old-growth subalpine forest in central Japan. Older seedlings (≥1 year) were more abundant on woody debris (WD), such as fallen logs, than on soil. It is known that this preferential seedling establishment on WD is determined by the first-year seedling establishment. The present results indicate that first-summer seedling survivorship clearly contributes to the creation of such seedling–substrate associations, because mortality during the first-summer was greater on soil than WD but that during the first-autumn/winter was not different. Although the standardized mortality rate of current-year seedlings on WD was not so different among the three seasons, that on soil significantly decreased in the winter; indicating that soil is not an unsuitable substrate for seedling survivorship during snow-covered winter. Thus, it can be concluded that biotic and abiotic factors enhancing seedling mortality on soil are most active during summer, and seedling–substrate associations seem to be determined mainly during the first-summer soon after seedling emergence. Furthermore, the first-year survivorship of P. jezoensis var. hondoensis, which has smaller-sized seeds/seedlings that are disadvantageous for early survival, decreased with progressing WD decay toward soil. This suggests that the properties of WD also affect current-year seedling survivorship, especially for species sensitive to substrate properties. In conclusion, initial survivorship affects seedling bank dynamics, and such early dynamics are greatly regulated by the highly heterogeneous substrate availability on forest floors.