四川盆地低山丘陵区森林承载力研究

本文以四川盆地低山丘陵区68个县森林资源现状为基础，探讨了森林承载力的概念，评价森林承载力的指标及提高森林承载力的途径。指出：森林承载力由森林生态系统物质产品的供应强度和非物质产品效能供应容量即环境负荷能力两个主要部分构成。通过合理调整农林结构，林种比例及树种配置，改善森林的内涵质等措施，显著地提高了森林承载力，使森林人口承载力和环境负荷能力由目前的超载转变为富余状况。     

梨感染茎痘病毒后过氧化物酶活性及其同工酶的变化研究

当年生早酥梨幼苗接种茎痘病毒（SPV）后．从第4天开始测定其叶片的过氧化物酶及其同工酶。结果表明．梨感染SPV后过氧化物酶活性显著高于健康无毒植株．其增酶高峰期在7天左右；过氧化物酶的同工酶也发生明显的变化．接种SPV后．有些弱带比无毒健株提早出现。     

现代化温室番茄植株各器官鲜物质和干物质分配规律的研究

试验结果表明：在本试验条件下，番茄植株鲜物质分配到根、茎、叶片和果实中的比例分别约为l％、20％、50％和30％，干物质分配到根、茎、叶片和果实中的比例分别约为2％、25％、47％和26％。果实干重占植株总干重的比例为26％，果实干重与营养器官干重的比率为34％。植株的平均干物质含量为10.2％，其中果实的干物质含量为5．0％，叶片、茎和根的干物质含量分别为11．6％、11．3％和14.9％。     

N-硝基-N-(2,4,6-三氯苯基)-N′-2-甲氧基苯基脲生物活性的研究

研究了N -硝基 -N - ( 2 ,4,6—三氯苯基 ) -N′ - 2 -甲氧基苯基脲对单子叶作物水稻的植物生长调节活性及对单子叶杂草稗的除草活性 ,结果表明 :在一定的浓度范围内 ,该化合物对水稻具有植物生长调节活性 ,对稗具除草活性。     

氟化钠对雏鸡半数致死量的测定

为弄清氟对禽类的毒性影响,选用1日龄罗曼褐蛋鸡56只,随机分为7组,每组8只,经饮水添加不同量的氟化钠,1次性灌喂,观察7d内动物中毒死亡情况,计算LD50等指标。结果：急性LD50及其95％可信限分别为960．48mg／kg,594．72～1326．24mg／kg。结论：鸡对氟的耐受量较大,禽产品中氟残留量不容忽视,它可能危及人类健康。     

Potential for the alleviation of arsenic toxicity in paddy rice using amorphous iron-(hydr)oxide amendments

Abstract

A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice (Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L^?1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces.     

矩形拟矮螨的生物学特性及其分布型初研

矩形拟矮螨的一生经卵、幼螨活动期、幼螨静止期和成螨４个虫态历期。在１５℃，２０℃，２５℃恒温条件下，从卵产出到成螨性成熟开始产卵的历期分别为（２３．９±３．４）天，（１９．５±２．６）天，（１０．１±１．８）天，平均每雌产卵量分别为（４０．１±１１．８）粒，（２９．６±５．８）粒，（１９．４±４．４）粒。经４０℃高温处理２４小时后，静止期幼螨、成螨的存活率分别为２５％，５．６％，卵不能孵化；活动期幼螨全部不能存活。在蘑菇生长季节，矩形拟矮螨有两个发生高峰期，分别出现在１０月中下旬和次年４月。矩形拟矮螨在蘑菇房内呈聚集分布，分布的基本成分为个体群。     

山槐心材提取物中有效抗菌成份的研究

以生物毒性试验为依据，对山槐心材中的有效抗菌成份进行了提取，分离及结构鉴定，初步证明了山槐的天然耐腐性主要来自于麦地卡品，反一金合欢醇等物质。     

褐飞虱迁飞轨迹研究

借鉴现代统计－天气理论中的大气传输与扩散模型，对褐飞虱秋季回迁的轨迹进行模拟，计算了回迁昆虫在高空１０００ｍ和１５００ｍ的迁飞轨迹，通过对比分析，发现两高度的轨迹在迁飞方向、迁飞速度和迁飞距离上存在着较大的差异；通过对迁飞风场和迁温度场的分析，进一步证实了１０００ｍ高度的迁飞轨迹模拟能够更直接、更准确地反映出昆虫迁飞的实际情况，同时对导致１０００ｍ和１５００ｍ两高度轨迹差异的环流进行了归类，定性地     

3个熟期类型大豆品种发育籽粒脂肪酸组分变化

超早,极早和中晚3个熟期类型大豆品种籽粒发育进程中,亚油酸含量持续上升,棕榈酸和硬脂酸含量缓慢下降,油酸含量先增后降;3个早熟品种的亚麻酸含量缓慢降低而中熟品种则几乎没有变化,亚油酸与籽粒发育天数呈显著正相关,棕榈酸和油酸呈显著负相关,其它脂肪酸之间及其与籽粒发育天数之间的相关关系因品种熟期类型而异。