一种新型双翻斗流量计的研制

根据国家林业部的行业标准LY／T1606-2003《森林生态系统定位观测指标体系》（Indicators system for long-term observation of forest ecosystem）,将地表径流量（Surface runoff）表述为：“降落于地面的雨水或融雪水,经填洼、下渗、蒸发等损失后,在坡面上和河槽中流动的水量。”     

配合翻斗雨量计测量径流的分流装置研制

使用翻斗式全自动雨量计测量森林地表径流和林区溪流流量时,因杂物堵塞雨量计受水口、流量超过量程造成数据缺失,量水堰测量仪器操作复杂。为此研制具有过滤功能的分流圆筒、径流分流槽、溪流分流槽,采用分流口配置类型和7种过滤材料,进行模拟测试和径流场测试。实验结果表明,坡面径流测量以径流分流槽效果较好,达到预期目标;分流口以高位倾斜配置分流效果较好;鱼缸过滤棉网及其与聚乙烯丝网、木条、钢丝网的组合材料过滤效果较好。     

一种新型融雪型雨雪量计的研制

1引言大气降水系指从天空降落到地面上的液态或固态(经融化后)的水。对于降雨量一般采用雨量计进行观测;对于降雪量,传统的方法是用雪深和融化后的水量表示。融雪型雨雪量计按融雪方式可分为不冻液式和电加热式;按融雪后采取的传感方式     

CR2-J(Ⅱ)型双翻斗雨量计的应用及分析

本文介绍了我国自主创新的CR2-J(Ⅱ)型双翻斗自记雨量计在成都温江实地检测性应用取得阶段性成果的过程。     

一种新型森林防火遮蔽式防护服的研制

遮蔽式防护服是一种专门为风力灭火机操作者设计的个人防护装备,其整体设计为组合式半包围结构,是由反射复合布和普通阻燃面料拼接制成,反射复合布的极限氧指数达到35,热防护系数为764 kW·s/m2.野外测试表明,该防护服穿着舒适、行动方便、反辐射热能力出众,符合风力灭火机操作者的实际防护需要.     

一种新型复合地板的研制

２４０及３２０目二道砂纸带；开料、四边铣榫时要求边线与端线相互垂直，凸凹榫在板坯厚度方向上要求高度统一，二者配合时，地板下面两边的高低差值不得大于０．１ｍｍ。③胶合阶段：各胶层胶合均采用我公司自行研制的防水胶，并要求涂布均匀，胶合强度应达到或超过ＧＢ９８４６．４中Ⅰ类胶合板的规定要求。采用以上结构和生产工艺生产的复合地板比普通实木地板有如下优点：①由于采用五层对称结构，芯层与其它各层纹理相互交错，使其因大气湿度变化而产生的变形极小，尤其是最厚的芯层是由小木条纵拼而成，能自动制约和弥补各小木条的微小干缩或湿胀，这就使整张产品在尺寸稳定性上是其它任何实木地板不可比拟的。②此种结构方式和工艺可以使成品在花色、品种上有更多的延伸。如：ａ．通过改变装饰层的树种和拼花形式，即可获得不同的产品品种；ｂ．热压后的板坯开料尺寸不同，即可获得不同幅面产品。我公司现在产品的幅面就有４００ｍｍ×４００ｍｍ、４００ｍｍ×１２００ｍｍ、３００ｍｍ×１２００ｍｍ等多种不同规格，以满足不同用途的需要；ｃ．还可以按客户的需要进行油漆、阻燃处理、厚度调整等。③装饰层的切片经过剪切挑选工序，可以避免诸多木材的天然缺陷，如初腐、变色、虫孔、节疤等     

一种新型角规的研制

针对普通测树角规在森林调查中存在的弊端，研究发明了一种能自动改正坡度的新型角规，详细介绍了其原理、结构设计及使用方法。经实地测试，精度达97．3％。     

电子测径仪的研制

电子测径仪属国内首创，它的研制成功标志着我国森林调查工具的一次重要突破。该仪器的研制主要是在测径仪动尺上设计了容栅测量电路和由ＣＭＯＳ电路组成的单片微处理器，单片机的信号输入接口与动尺上的容栅感应电极之间，经数据线传输；设计了由ＣＤ４０２２和ＣＤ４０９４组成的串并转换电路，将容栅感应电极拾取的测量信号脉冲串转换为并行数据，以便于微处理器处理，ＬＣＤ显示输出信号，也可通过接口将数据输出到通用计算机上作更复杂的处理和打印，或与数据采集仪联机解决野外数据的存储、传输问题。     

苏联研制的一种新型带锯机

苏联Archangel的木材加工机械化科研中心最近研制出了一种新结构带锯机(见图)。这种带锯机的带锯条不是在通常的驱动锯轮上转动,而是在一组不旋转的半圆弧导轨上转动。其中,上导轨能上下移动,下导轨固定,两导轨工作表面充有压缩空气,     

一种新型的树干径流采集器的研制

本文介绍了一种在森林生态系统水量平衡观测中树干径流采集的新装置。常规的采集方法是用Φ12~Φ16的胶皮管,从中剖开,蛇形缠绕并固定在树干上,让树干径流沿剖开的胶管流入承水器中。该方法胶管易老化,径流易“跑”、“漏”,观测误差较大。CR2-Y型树干径流采集器对胸径大于15 cm的林木,采用特定横截面,抗老化的橡塑复合胶带,蛇形缠绕并固定在树干上。对树干径流进行有效导流,减少了树干径流的观测误差;对胸径小于或等于15 cm的林木则采用0.28mm厚的铝板按不同胸径预制成正圆锥管展开的扇形片,现场合围在树干上,经安装导水管,填充剂,密封胶处理后,用相应大小的喉箍固定在树干上。这样有效地截流,提高了树干径流观测中的精度,减少了观测误差。     

Photosynthetic capacity in a central Amazonian rain forest

The vertical profile in leaf photosynthetic capacity was investigated in a terra firme rain forest in central Amazonia. Measurements of photosynthesis were made on leaves at five levels in the canopy, and a model was fitted to describe photosynthetic capacity for each level. In addition, vertical profiles of photosynthetic photon flux density, leaf nitrogen concentration and specific leaf area were measured. The derived parameters for maximum rate of electron transport (J(max)) and maximum rate of carboxylation by Rubisco (V(cmax)) increased significantly with canopy height (P < 0.05). The highest J(max) for a single canopy level was measured at the penultimate canopy level (20 m) and was 103.9 &mgr;mol m(-2) s(-1) +/- 24.2 (SE). The highest V(cmax) per canopy height was recorded at the top canopy level (24 m) and was 42.8 +/- 5.9 &mgr;mol m(-2) s(-1). Values of J(max) and V(cmax) at ground level were 35.8 +/- 3.3 and 20.5 +/- 1.3 &mgr;mol m(-2) s(-1), espectively. The increase in photosynthetic capacity with increasing canopy height was strongly correlated with leaf nitrogen concentration when examined on a leaf area basis, but was only weakly correlated on a mass basis. The correlation on an area basis can be largely explained by the concomitant decrease in specific leaf area with increasing height. Apparent daytime leaf respiration, on an area basis, also increased significantly with canopy height (P < 0.05). We conclude that canopy photosynthetic capacity can be represented as an average vertical profile, perturbations of which may be explained by variations in the environmental variables driving photosynthesis.     

Pooling of CO2 within a small valley in a tropical seasonal rain forest

CO₂ concentrations and related environmental factors were measured in an Asian tropical rainforest located in a small valley in Xishuangbanna, SW China, with the aim of investigating the CO₂ pooling effect and its mechanism of formation. Pooling of CO₂ was observed during the evening (1600?C2200?hours local time); the accumulated CO₂ subsequently flowed away after dusk. We consider that along-slope drainage flow, soil CO₂ efflux, and temperature inversion contribute to the development of CO₂ pooling. A new model is proposed to track the mechanism of the formation and dissipation of CO₂ pooling (e.g., drainage flow, compensatory mechanisms). Given its influence on the storage term, we suggest that CO₂ pooling and subsequent disappearance should be taken into account when calculating eddy covariance and other micrometeorological measurements of carbon flux for valley sites.     

一种应用型角规设计

针对常用自平杆式角规在实践中出现的小轴转动迟滞和指标拉杆阻滞等问题,遵循角规测树原理,贯彻工业品绿色设计理念和人性化设计理念,提出一种应用型角规测器。设计的角规测器较自平杆式角规更便携耐用。     

Effects of bamboo stands on seed rain and seed limitation in a rainforest

Bamboos often negatively affect tree recruitment, survival, and growth, leading to arrested tree regeneration in forested habitats. Studies so far have focused on the effects of bamboos on the performance of seedlings and saplings, but the influence of bamboos on forest dynamics may start very early in the forest regeneration process by altering seed rain patterns. We tested the prediction that the density and composition of the seed rain are altered and seed limitation is higher in stands of Guadua tagoara (B or bamboo stands), a large-sized woody bamboo native from the Brazilian Atlantic Forest, compared to forest patches without bamboos (NB or non-bamboo stands). Forty 1 m² seed traps were set in B and NB stands, and the seed rain was monitored monthly for 1 year. The seed rain was not greatly altered by the presence of bamboos: rarefied seed species richness was higher for B stands, patterns of dominance and density of seeds were similar between stands, and differences in overall composition were slight. Seed limitation, however, was greater at B stands, likely as a resulted of reduced tree density. Despite such reduced density, the presence of trees growing amidst and over the bamboos seems to play a key role in keeping the seeds falling in B stands because they serve as food sources for frugivores or simply as perches for them. The loss of such trees may lead to enhanced seed limitation, contributing ultimately to the self-perpetuating bamboo disturbance cycle.     

Variation in photosynthetic light-use efficiency in a mountainous tropical rain forest in Indonesia

Photosynthetically active radiation (Q)-use efficiency (epsilon) is an important parameter for deriving carbon fluxes between forest canopies and the atmosphere from meteorological ground and remote sensing data. A common approach is to assume gross primary production (P(g)) and net primary production (P(n)) are proportional to Q absorbed by vegetation (Q(abs)) by defining the proportionality constants epsilon(Pg) and epsilon(Pn) (for P(g) and P(n), respectively). Although remote sensing and climate monitoring provide Q(abs) and other meteorological data at the global scale, information on epsilon is particularly scarce in remote tropical areas. We used a 16-month continuous CO(2) flux and meteorological dataset from a mountainous tropical rain forest in central Sulawesi, Indonesia to derive values of epsilon(Pg) and to investigate the relationship between P(g) and Q(abs). Absorption was estimated with a 1D SVAT model from measured canopy structure and short wave radiation. The half-hourly P(g) data showed a saturation response to Q(abs). The amount of Q(abs) required to saturate P(g) was reduced when water vapor saturation deficit (D) was high. Light saturation of P(g) was still evident when shifting from half-hourly to daily and monthly time scales. Thus, for a majority of observations, P(g) was insensitive to changes in Q(abs). A large proportion of the observed seasonal variability in P(g) could not be attributed to changes in Q(abs) or D. Values of epsilon(Pg) varied little around the long-term mean of 0.0179 mol CO(2) (mol photon)(-1) or 0.99 g C MJ(-1) (the standard deviations were +/- 0.006 and +/- 0.0018 mol CO(2) (mol photon)(-1) for daily and monthly means, respectively). In both cases, epsilon(Pg) values were more sensitive to Q(abs) than to daytime D. These findings show that the current epsilon-approaches fail to predict P(g) at our tropical rain forest site for two reasons: (1) they neglect saturation of P(g) when Q(abs) is high; and (2) they do not include factors, other than Q(abs) and D, that determine seasonality and annual sums of P(g).     

新特蔬菜的开发利用

新特蔬菜又名特色蔬菜或特种蔬菜 ,可分为外引、地产特优和野菜珍稀三大类 ;按功能功效又可分为“食疗保健蔬菜”、“芳香蔬菜”、“调味蔬菜”及“观赏蔬菜”等。下面将新特蔬菜的功效及开发利用价值介绍如下。1　食疗保健蔬菜的利用酸味蔬菜　一般酸 (涩 )味的蔬菜含维生素C和有机酸 ,具有生津止咳、消食开胃、止血等功效 ,对久泻、遗尿、咳嗽、气喘、遗精、阳痿等症有治疗作用。常见酸味蔬菜有 :落葵、马齿苋、酸浆 (性寒凉 ) ;韭菜 (性温热 ) ;蕃茄、苜蓿、西番莲、芡实 (性平 )。其中马齿苋为一年生草本植物 ,除高寒地区外 ,我国各地…     

Seed rain of ponderosa pine beneath partial overstories

An analysis was conducted of the 1999 ponderosa pine (Pinus ponderosa var. ponderosa Dougl. ex Laws.) seed crop at two stands of differing overstory density in each of two sites that differed in productivity (forest community series) on the east slope of the Cascade Range in central Oregon, USA. A total 2,166 viable seeds were collected between 2 September 1999 and 6 June 2000. Total seed quantities varied more by site than by tree density, with the xeric site producing six-fold greater seed yields. Within each site, the stand of higher density produced more viable seed. Per-tree cone yields were also greater at the site of lesser productivity. At three of the four stands, tree fecundity (as measured by cone counts) was positively related to diameter at breast height and height, but not to live crown ratio. A difference in temporal seedfall patterns among the two sites occurred late and was relatively minor: most seedfall occurred within the first month after it started regardless of absolute seed production. Seedfall distribution varied spatially within stands, but no seed trap (of 55) received less than an equivalent 28 thousand seeds per hectare. Seedfall was not perceived to be a limiting factor on natural regeneration at any of the four partial-overstory stands in this study.     

新型实木面层强化地板的研制

通过对普通强化地板生产工艺的改进，新型实木面层强化地板的生产的要求，解决了生产过程中的难点问题．实现了强化地板面层的实木化。     

Effect of laminate configuration on the modulus of elasticity of glulam evaluated using a strain gauge method

The purpose of this study was to measure the strain of glulam laminae by affixing a strain gauge at the central axis of the lateral face in order to determine the effect of the configuration of the glulam. Japanese cedar and southern pine were used in the study. The strain and stress of the laminae during the bending test were recorded, and the modulus of elasticity (MOE) was calculated. The influence of the MOE of the adhesive layers was also considered. Results showed that the MOE of the laminated elements increased as its specific gravity increased, although the specific gravity was not the only factor evaluated. The MOE of glulam (E _bsg) measured by the strain gauge method was very close to the observed MOE of glulam (E _b) and a significant linear relationship was identified. The MOE (e) of laminae measured by the strain gauge method was very close to that determined (E) under the “free condition” before bonding. The difference between the modified MOE (E _bsa) and E _bsg was not significant. The MOE of glulams made of heterogeneously graded lumbers were about 23% and 31% larger than the average MOE of their laminae for Japanese cedar and southern pine, respectively. The actual neutral axis was just below the longitudinal center line. It shifted slightly within the proportional limit range and moved downward when the load increased.