Relationship between stomatal behavior and characteristics of photosynthesis and transpiration of Adenophora Iobophylla and A. potaninii at different altitudes

The photosynthesis and transpiration characteristics ofAdenophora Iobophylla and A. potaninii, as well as stomatal behavior such as stomatal size, stomatal density, stomatal open and stomatal conductivity were measured at different altitudes. The relationship between the photosynthesis and transpiration characteristics and the stomatal behavior was analysed by correlation coefficient and path coefficient analysis with altitude changes.The results showed that the influences of stomatal behavior were not evident on the photosynthesis and transpiration characteristics of A. Lobophylla, but evident on that of A. potaninii.     

Mathematical Model of Flow Process in 40t/h Pyroflow Circulating Fluidized Bed Boiler

A mathematical model is presented to describe the fluiddynamics processes for the combustion system of 410t/h Pyroflow CFB boiler.A core annulus structure with solid dispersion from core to annulus is considered,and the influence of coal particles fragmentation,attrition and broad size distribution of feeding coal and bed inventory on hydrodynamics is specially taken into account.The simulation results show that the CFB boiler has good hydrodnamic characteristics and high hot cyclone efficiency.     

亚洲草地在目前和将来的作用

亚洲草地的自然环境亚洲幅员辽阔,具有略呈梯形的大陆躯干,地形中高周低。中部高耸,多崇山峻岭和高原,四周低下,多低山丘陵和平原。大陆东缘,自北而南具有一系列向太平洋凸出的弧形列岛,地表起伏较大。亚洲东濒太平洋,西临印度洋,北滨北冰洋,西达大西洋的属海地中海和黑海。由于海陆间巨大的热力差异及季节变化或迭加行星风带的季节移动,使亚洲的东部、东南部和南部     

Analysis and comparison on population dynamics betweenAdenophora lobophylla andAdenophora potaninii by leslie matrix

The population dynamic tendency ofAdenophora lobophylla Hong as an endangered species andAdenophora potaninii Korsh as widespread species, has been predicted by the Leslie matrix. And the comparison and analysis on the age structures between two species have been carried out in this paper. The results demonstrate theA. lobophylla populations which have the reasonable age structures perform slowly negative or positive increment at altitude 2300–3400 m. Especially. below altitude 2700 m. there are many populations performing seriously declining tendency. Contrary.A potaninii populations could adapt to environment perfectly at the corresponding condition without finding the population which performs the seriously declining tendency. The differences in developing tendency of population between the two species demonstrate thatA. lobophylla populations have the weaker ability to adapt to the external unfavorable conditions. The project was supported by Chinese Natural Science Foundation. (No. 3939150) The experiment carried out at the Botanical Department of University Federal Sao Carols in Brazil (Responsible Editor: Zhu Hong)     

水稻(银坊)×高梁(亨加利)受精过程及胚胎发育的细胞学观察

本研究以石蜡制片方法观察高粱花粉管伸入水稻胚囊后,释放精子,两亲性细胞融合过程及胚胎发育情况。观察表明:高粱精子能够与水稻卵子融合形成合子。少数合子(占0.44%)进一步分裂,发育成幼胚组织。本文对远缘杂交性细胞融合的潜在价值,促进杂种胚胎继续发育的方法及某些远缘杂种形成的机制进行了探讨。     

川西北地区裂叶沙参与泡沙参所在群落种间联结性对照研究

为了探讨裂叶沙参和泡沙参所在群落特征及其种间关系,应用方差比率法,并通过２×２列联表进行χ２检验的方法,分别在川西北地区对濒危种裂叶沙参和广布种泡沙参所在群落中２３和２６个常见植物种分别进行了总体相关性和各种对间的联结性检验,同时利用Ｊａｃｃａｒｄ指数测定了各种间的关联度。结果表明,裂叶沙参与泡沙参所处群落中各种群间在总体上无显著性联结。在裂叶沙参所在群落中２３个种群间,仅２％的种对间Ｊａｃｃａｒｄ指数大于０５;在泡沙参所在群落中２６个种群间,仅３％的种对间Ｊａｃｃａｒｄ指数大于０５。裂叶沙参和泡沙参所处群落中种间关系的不稳定性是由于人类活动对植被的破坏及环境旱化所导致。泡沙参在严酷的环境条件下种群呈扩展趋势,而裂叶沙参在相同或较好的环境条件下种群呈衰退趋势,说明裂叶沙参在其内在的生物学、生态学习性方面存在着导致种群衰退的机制     

Study on the Yield Reduction Mechanism of Soybean Planted under Continuous and every Second Year Cropping Conditions

Three-year investigation was conducted to demonstrate the mcchanism of reduction of soybean yield aroused by continuous and every second year cropping.Compared to normal cropping,there are many unfavorable changes in some major elements of soybean plant and soil environmeng.Chloropyll content was .Phosphorous content of soybean plant was decreased seriously.Potassium content was lower while calcium content was higher.Magnesim content was wot affected and decreased in susceptive varieties.Some deseases and insects of soybean under continuous and very second year cropping conditions became serious as continuous years prolonged.Organic matter content tended to go down from normal rotation to continuous cropping .Amount of bacteria and antinomyces decreased while amount of fungi increased.The evelopment of symbiotic nitrogen fixation system was deteriorated.     

黑龙江省农作物冷害气候区划

在调查研究和科学实验的基础上,分析出符合黑龙江省实际的窕作物冷害指标和霜冻指标。延迟型冷害指标是随各地温度水平不同而改变的动态值,障碍型冷害是以水稻抽前第９天至第１１天,日平均气温连续３ｄ低于１８℃为指标。霜冻指标是以各地日平均气温稳定通过１０℃终日的８０％保证率日期为标准,用日最低气温≤０℃的初日去衡量,后者小于前者时测定义为早霜冻日期。为了有针对性的防御冷害,将黑龙江省划分为８个不同程序的冷害     

厚朴外观性状与内在品质的关系

采用高效液相色谱法测定了采自国内厚朴主产区的70个单株的树皮样品的厚朴酚及和厚朴酚含量。结果表明：厚朴树皮外面性状与内在品质存在显著的相关性。皮厚、表面粗糙、油性足、粉末颜色深和纤维含量少的厚朴品质好,反之品质较差,其中,粉末颜色和皮厚是外观性状中的主要性状。它们是制定朴品质标准的最主要外观因素。同时,也为厚朴遗传改良的品质判别提供简单且可操作的外观指标。     

使用Li-6400测定森林土壤呼吸应注意的几个问题

正确使用Li-6400进行森林土壤呼吸测定是保证测定精度的前提.本文以落叶松林为例,对Li-6400使用过程应该注意的问题进行了研究.结果表明:塑料圈至少应该测定前12小时进行设置,以减少土壤CO2涌出效应对呼吸的影响,而且塑料圈插入深度对测定结果影响很大:当塑料圈插入过浅时横向气体扩散及塑料圈不稳定而造成测定时CO2的再涌出效应使土壤呼吸测定值偏高;而当插入深度过深时,切断根系导致根系呼吸下降,最活跃的土壤表层呼吸受塑料圈阻隔导致的土壤微生物呼吸测定值下降,这些现象共同造成显著低估土壤呼吸测定值.此外,在晴天白天大部分时间内目标[CO2]值设定为外界相应时段的[CO2]平均值,可以保证测定误差小于5%,而在清晨和傍晚进行测定时,则应该及时调整目标值为外界[CO2]保证测量准确性.这一测定原则在实际测定中具有较高的实用性.