砂石山区板栗增产技术初试

费县有板栗１０００多公顷，２００多万株，品种有实生板栗和“石丰”、“金丰”等优良品种。由于板栗多分布在旱薄山地上，立地条件差，严重的影响着板栗的产量，优良品种的增产潜力得不到充分发挥。为此，作者于１９９７年对板栗作了穴贮肥水加地膜覆穴的增产技术试验，...     

赤霉素,稀土,高产素在板栗增产上的应用

在实生板栗上改换优良品种，应用赤霉素、稀土、高产素，在板栗生长的不同时期进行喷施，对板栗生长和结实有明显的增产效果。     

提高板栗产量的有效措施

提高板栗产量的有效措施河北省燕山山区是著名的京东板栗的集中产区，但由于管理粗放，存在大量的无产和低产树。笔者从当前生产出发，提出如下增产措施。１选用早果丰产优良品种燕山栗区有许多早果高产优良品种，主要有：燕山早丰、燕奎、燕红、毛栗１号、下左２号、大板...     

板栗穗条的增产措施试验

在毕节市分布的2个板栗地方优良品种和引进的11个板栗优良品种中选出优良单株,培育成嫁接苗后,建立13个分区的采穗圃,开展无性系鉴定和引进优良品种比较试验。利用双因素裂区田间试验设计方法,对采取施肥及整形修剪处理措施后板栗树穗条的增产效果进行试验,获得穗条增产措施的最佳组合及产量变化趋势。     

毕节地区板栗优树选择及分级

经过１９９０年￣１９９３年连续４年开展的板栗优良品种调查及优树选择，毕节地区板栗优良品种有油砂板栗和辅处板栗；在这２个优良品种中选出优树１０株。运用Ｆｕｚｚｙ二级评判模型，评判分出Ｉ级优树２株，Ⅱ级和Ⅲ级优树各４株。     

退耕还林几种复合经营模式及配置技术

果—茶复合型1.1板栗—茶树复合型(1)板栗Castanea mollissi maBlume:选择宜昌浅刺大板栗,它是早实、丰产的优良品种。整地时,应根据山地不同坡度而定,坡度一般在20°~25°时,沿等高线挖穴。定植时,一般每穴内施有机肥25kg,并混入部分磷肥。选用粗壮无病虫害的嫁接苗或者是实生     

板栗芽砧嫁接袋苗培育技术

<正>云南现有的板栗品种多而杂, 长期以来,由于世代自然杂交,遗传性状多样,种质资源丰富。从上个世纪20年代以来,科研部门和生产部门从省外引进板栗优良品种试验,筛选出适合云南发展的多个优良品种,之后,云南省林科院从中选出了多个适合云南发展的板栗新品种在生产中推广应用。     

安徽广德山区板栗品种资源及其利用

通过对安徽广德山区板栗品种调查，该区有优良品种８个，较优良品种８个，５个劣质品种，对各品种的主要性状作了描述，列出了优良品种检索表，并阐明了各个品种的利用前景。     

板栗萌蘖灌木林改造技术探究

招远市部分山区村庄板栗萌蘖灌木林面积较大,近年来开始通过一系列科学营林措施进行改造,通过几年努力改善了原有林分质量,提高了它的适应性和经济效益,具有较高的推广价值。本文总结了板栗整形修剪、嫁接优良品种、清理整地挖穴,防治病虫害等方面的技术,供生产经营者和研究者参考。     

提高山地板栗初期生长量及产量的试验研究

板栗的初期营养生长对板栗的结实及个体发育影响很大。通过大量的实测资料进行分析，探讨华北花岗岩山地水土流失地区土地生产力的效益，对板栗的早实，丰产有着重要的意义。结果表明：垫腐秸可使地径增粗３７．２％，修盘扩穴可使地径增粗２８．８％，枯秸覆盖可使地径增粗２６．１％，平均单株比对照增产以处理１为最高１５５．３％，其次是处理４为１１４．７％。已达到提高板栗初期生长量及产量实验的目的。     

Chemical kinetics of Japanese cedar,cypress, fir,and spruce and characterization of charcoal

 Thermogravimetric and differential thermal analyses techniques have been applied to investigate the thermal degradation characteristics and chemical kinetics of Japanese cedar, cypress, fir, and spruce. The decomposition of the components could be modeled by an Arrhenius kinetic expression. The kinetic parameters were extracted from the thermogravimetric data using least-squares techniques. The heating rates used for the analyses were 10°, 5°, and 0.33°C/min; and the activation energy and reaction order of the above woods were 7.54, 8.39, 2.87, and 7.88 kJ/mol and 0.71, 0.64, 0.44, and 0.63, respectively. Finally, carbonization was done to produce charcoal from these woods under various operating conditions, and the charcoal was characterized in respect to yield, heating value, electrical conductivity, and X-ray diffraction. The quality of the charcoal from fir was the best among the four types of wood. The charcoal produced is inferior to binchotan (white charcoal) in respect to electrical conductivity and crystalline structure. Received: February 13, 2002 / Accepted: July 12, 2002 Acknowledgment The authors express their gratitude to Professor Yoshida of Applied Chemistry in Tokyo Metropolitan University for performing the TG/DTA in his laboratory and for his valuable suggestions about the analyses.     

Behavioral responses,rate of mortality,and oviposition of western cherry fruit fly exposed to malathion,zeta-cypermethrin,and spinetoram

Western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), is a pest of sweet and tart cherry, Prunus avium L. (L.) and P. cerasus L., respectively, in western North America. This fly is commonly controlled with spinosad bait sprays. Spotted wing drosophila, Drosophila suzukii Matsumura, is potentially a new pest of cherries in this region that could be a threat to orchards at the same time as R. indifferens. Drosophila suzukii apparently is not controlled using spinosad bait sprays, but may potentially be controlled using malathion, zeta-cypermethrin, and spinetoram. However, how well these last three materials protect fruit against reproductively mature R. indifferens is not known. In laboratory observations, R. indifferens spent the least amount of time on cherries treated with zeta-cypermethrin, possibly because of its toxicity and irritant effects. In laboratory experiments, zeta-cypermethrin killed flies more quickly than malathion and spinetoram, causing up to 100% mortality 2 h after exposure. Zeta-cypermethrin prevented all oviposition when flies walked on dried residues for 20–25 min or were directly sprayed, and then exposed to cherries with dried residues, simulating exposure of mature female flies in a treated orchard. Malathion and spinetoram reduced oviposition compared with controls, but did not prevent it, when flies contacted residues or were directly sprayed at a high volume. Results suggest zeta-cypermethrin is the most effective of the three materials at protecting cherries against mature R. indifferens and could be used in an integrated control program for it and D. suzukii.     

Effects of alkali,mild steam,and chitosan treatments on the properties of pineapple,ramie, and sansevieria fiber bundles

This study focused on the effects of treatments of alkali, mild steam, and chitosan on the surface morphology, fiber texture, and tensile properties of pineapple, ramie, and sansevieria fiber bundles. The fibers were treated with NaOH (2%), mild steam (0.1 MPa), and chitosan solutions (4% and 8%). The properties of these treated fibers were characterized and compared with the untreated fibers. Field emission scanning electron microscopy (FE-SEM) was used to observe the surface morphology of those fibers. X-Ray diffraction (XRD) spectroscopy was used to observe the fiber textures. Tensile properties of the treated and untreated fibers were also recorded. SEM micrographs showed that the surfaces of the NaOH-treated fibers were more damaged than those of the steam-treated fibers. The 4% chitosan solution covered the fiber surface more uniformly than the 8% chitosan solution. The steam-treated fibers had higher values of degree of crystallinity, crystallite orientation factor, and crystallite size than the NaOHtreated fibers. Ramie fiber showed greater mechanical properties than the other fibers. The values of tensile strength, Young’s modulus, and toughness of the steamtreated fibers, which were similar to those of the 4% chitosan-coated fibers, were higher than those for the other treatments.     

Sciences,knowledges, and the practice of forestry

We address the question of how credible knowledge that will contribute to more effective forest policy and management can be produced. We argue that some forest-related knowledge-producing practices of professional scientists and of local people are similar, and given the differences in the knowledge they produce, we explore how they might be used productively together to create better understandings of forests with resulting better forestry practice and policy. Using a case study of participatory forest ecology research, we demonstrate that when professional (conventional) scientists do research in collaboration with local experts (civil scientists), the resulting knowledge can be more accurate and more policy relevant than they could produce doing research on their own or only with other conventional scientists.     

核桃采收、脱皮、漂白及坚果分级技术要点

本文就核桃采收时间、脱皮方法及坚果分级标准进行了初步研究总结,为实现核桃优果优价、提质增效提供了切实可行的理论依据。     

Integration of pines,pastures, and cattle in south Georgia,USA

Agroforestry Systems - Native forages of southern United States are frequently low in nutrients and poorly digestible, while improved pastures are the opposite. Since this area produces rapid...     

林地土壤pH值，磷，钾，有机质和水含量具有可变和可控性

对取自山西省北部不同地点、不同层次的土样的pH值、磷、钾、有机质、水含量的变化进行了研究。结果表明：林地土壤理化性质具有可变性的可控性。     

Seedling emergence, growth, and allocation of Oriental bittersweet: effects of seed input, seed bank, and forest floor litter

The establishment of invasive plant populations is controlled by seed input, survival in the soil seed bank, and effects of soil surface disturbance on emergence, growth, and survival. We studied the invasive vine Celastrus orbiculatus Thunb. (Oriental bittersweet) to determine if seedlings in forest understory germinate from the seed bank or from seed rain. We also conducted a greenhouse experiment to investigate the role of leaf litter mass and physical texture on seedling survival, growth, and allocation. In the understory of an invaded mixed hardwood forest, we measured seed input, seedling emergence with seed rain, and seedling emergence without seed rain. Mean seed rain was 168 seeds m⁻²: mean seedling emergence was 107 m⁻², and there was a strong correlation between seed rain and seedling emergence. The ratio of seedlings to seed input (0.61) was close to the seed viability (0.66) leaving very few seeds to enter the seed bank. Seed bank germination under field conditions was low (1 seedling m⁻²). Soil cores were incubated in a greenhouse to determine seed bank viability, and germination from these soil cores did not occur. To determine how litter affects seedling establishment and growth, we measured seedling emergence and biomass allocation in a greenhouse experiment. Seeds were placed below intact and fragmented deciduous leaf litter in amounts ranging from zero to the equivalent of 16 Mg ha⁻¹. Seedling emergence was not affected by fragmented litter, but decreased to <20% as intact litter increased to 16 Mg ha⁻¹. Increasing litter resulted in greater allocation to hypocotyl and less to cotyledon and radicle, and this effect was greater in intact litter. C. orbiculatus seedlings achieve emergence through forest floor litter through plasticity in allocation to hypocotyl growth. The low survival of C. orbiculatus in the seed bank suggests that eradication of seedling advance regeneration and adult plants prior to seed rain may be an effective control strategy. However, the intact forest floor litter of an undisturbed forest will not prevent seedling establishment.