舟蛾赤眼蜂生物学特性

舟蛾赤眼蜂在淮北地区自然界能安全越冬,每年完成２０～２２个世代。环境温湿度、风和光照等自然因子对其发育和活动有明显影响,发育的适宜温度为２４．９～２８．７℃,相对湿度为８０％左右。常年平均寄生率为 １４．８１％;垂直向上活动范围可达 ６～８ｍ,水平扩散可达 ３５ｍ。     

不同温度和土壤含水量对大斑芫菁生长发育的联合作用

在室内人工饲养大斑芜蓄,研究了不同温度、土壤台水量对大斑芜蓄生长发育及其卵的孵化串的联合作用。结果表明：大斑芜蓄不同生长发育时期对温度、土壤台水量的要求有所不同,１—６龄幼虫发育速率最快时的温度和土壤台水量依次为：３２．６℃、６％;３５．６℃、６％;３６．３℃、６％;３８．０℃、６％;３５．６℃、６％;３８．０℃、７．１％,蛹发育速率最快时的温度、土壤台水量为３７．１℃、６％。卵孵化率最高时的温度、土壤台水量为３４．０℃、１２％,卵发育速率最快时的温度、土壤台水量为３３．２℃、７％,     

环境条件对水网藻(Hydrodictyon reticulatum)生长的影响

研究了温度、光照强度及Ｎ、Ｐ浓度与水网藻生长的关系．结果表明,水网藻能在较大的温度范围（１０～３１℃）、光照强度（３００～５３００Ｌｘ）和Ｎ浓度（１．０～８４．０ｍｇ·Ｌ－１）和Ｐ浓度（０．０５～３．７２ｍｇ·Ｌ－１）等条件下生长．最适生长温度为２５℃,当光照强度大于１３００Ｌｘ,Ｎ、Ｐ含量分别为１６．８～５０．４和０．７４４～２．２３ｍｇ·Ｌ－１时,水网藻生长良好．低温有利于水网藻忍耐低光照和低Ｎ低Ｐ．     

紫菀花序芽培养及植株再生

１植物名称紫菀（Ａｓｔｅｒｔａｔａｒｉｃｕｓ）。２材料类别花序芽。３培养条件愈伤组织、不定芽诱导及增殖培养基：（１）ＭＳ＋６－ＢＡ０．５～２．０ｍｇ·Ｌ－１（单位下同）;生根培养基：（２）ＭＳ＋ＮＡＡ０．５～２．０＋６－ＢＡ０．２,（３）１／２ＭＳ（大量元素减半）＋ＮＡＡ０．５～２．０＋６－ＢＡ０．２。上述培养基均加０．８％琼脂和３％蔗糖,高温高压灭菌前ｐＨ值调至５．８。培养温度为（２３１２）℃,每天光照１２ｈ,光照度为１５００～２０００ｌｘ４生长与分化情况４．１愈伤组织及不定芽的诱导剪取长约０…     

温度对美洲斑潜蝇发育,存活和繁殖的影响

探讨了在光照周期为１４Ｌ１０Ｄ、Ｒ．Ｈ．为７０ ％ ±５ ％ 的恒温（１２ ～３５ ℃） 条件下美洲斑潜蝇的发育、繁殖和存活,求得美洲斑潜蝇世代的发育起点温度与有效积温分别为８ ．７７ ℃和２９５ ．６９ 日度,给出了温度与各虫态发育速率间的函数关系．２０ ～２７ ．５ ℃时存活率较高,死亡主要发生在蛹期,３５ ℃下蛹不能羽化．成虫寿命随温度的升高而缩短; 种群增长指数于２７ ．５ ℃时达到最高．     

青蒿毛状根合成青蒿素的培养条件研究

对影响青蒿（ＡｒｔｅｍｉｓｉａａｎｎｕａＬ．）毛状根生长及青蒿素合成的培养条件进行了研究,确定最适的培养条件为：初始ｐＨ５．８～６．０,摇瓶转速１３０～１５０ｒ／ｍｉｎ,摇瓶装液量体积分数为２５％,光照周期为１６ｈ／ｄ,温度为３０℃。在此条件下,经过２５ｄ培养获得青蒿素产量为２２３．３ｍｇ／Ｌ。     

银王亮丝草的试管微繁殖

１植物名称银王亮丝草（Ａｇｌａｏｎｅｍａ　ｃｏｍ－ｍｕｔａｔｕｍｃｖ．"ＳｉｌｖｅｒＫｉｎｇ”）,又名银王粗肋草、银王万年青、银皇帝。２材料类别带腋芽的茎段。３培养条件以ＭＳ为基本培养基。芽诱导培养基附加６－ＢＡ２．０～２．５ｍｇ·Ｌ－１（单位下同）;芽增殖培养基附加６－ＢＡ４．０～４．５及ＮＡＡ０．０１～０．０２;生根培养基采用３／４ＭＳ附加ＩＢＡ３．０～３．５及ＧＡ３３,０。所有培养基蔗糖及琼脂含量分别为３％和０．７５％,ｐＨ值均调至５．８。培养温度２６～２８℃,光照８～１０ｈ·ｄ－１,光照…     

黄土高原刺槐林间伐改造研究

通过对 9年生刺槐 (Robiniapseudoacacia)林以 3种不同保留密度进行间伐改造 ,并对其林内光照、温度和土壤水分环境因子以及林下植被层生物多样性、生产力和林冠层林木的生长情况与原林分进行对比分析 .结果表明 ,间伐改造能改善林木及林下植被层生长发育的环境条件 ,促进林下植被层生物多样性和生物产量的提高 ,增加林木的生产能力 .间伐保留密度达到 1110株·hm-2 时 ,在整个生长季 ,林地土壤水分比原林分提高约 40 %,不仅林下植被层的生物多样性和生物量有大幅度提高 ,而且林冠层林木的生产力达到较高水平 ;如果继续加大间伐强度 ,林下植被层和林木个体的生长已达到最大极限 ,将不再提高 .因此 ,1110株·hm-2 左右的保留密度是可考虑的间伐强度 .     

环境因子对竹子开花影响研究

四川雅安地区刺竹和水竹开花年(2001～2006年)1月均温分别高出未开花年(1985～2000年)和多年(1985～2006年)平均值0.29℃和0.225℃;7月均温分别高出未开花年和多年平均值0.958℃和0.697℃;开花年年降水量分别比未开花年和多年平均值少124.9 mm和90.8 mm.开花和未开花水竹林小生境生态因子的调查显示,处于阳坡、光照条件好的样地开花明显多于处于阴坡、光照条件较差的样地;林内温度和湿度与竹子开花显著相关,开花样地内早上9时和中午2时平均温度和湿度均比未开花样地高.表明充足的光照、较高的林内温度、湿度,干旱和气温的升高在一定程度上起到了诱导和促进竹子开花的作用.     

乳山湾浮游植物与环境因子的相关关系研究

研究了１９９５年乳山湾６～９月浮游植物与环境因子的关系,结果表明,浮游植物与环境因子有着密切关系,无机营养盐与浮游植物数量有较好的负相关关系;无机氮和无机磷与浮游植物相关系数分别为－０．６７和－０．８０。而溶解氧和叶绿素－ａ与浮游植物呈较密切的正相关关系,其相关系数分别为０．９２和０．８５。由Ｎ／Ｐ分析,除８月下旬外,其它月份无机氮对于浮游植物的繁殖生长均显得相对紧缺。     

内蒙古半干旱草原区沙地植物群落光合特征的动态研究

沙蒿(Artemisia intramongolica)群落是半干旱草原地区沙地的重要植被类型,分别在植物的生长前期、中期、盛期和后期采用便携式光合测定仪和大型同化分析仪测定了沙蒿叶片和沙蒿群落的光合动态。单叶和群落的光合速率日进程类型随气候的不同而异,瞬时光合速率主要决定于光合有效辐射强度(PAR)。土壤干旱大大降低了单叶和群落的光合能力,晴天土壤湿润时气温和空气湿度控制着叶片的光合速率,午间大气湿度降低是光合午休的主要外因。叶片的蒸腾速率与气温呈显著线性相关,植物的光能和水分利用效率也主要取决于PAR和气温,随着PAR和气温的升高利用效率下降。沙蒿叶片光能利用效率在后期也能保持较高水平。沙蒿对土壤干旱和高温具有一定的适应性,在土壤湿润时能迅速提高光合速率,形成较大的生物量。但是沙蒿的蒸腾速率高,水分利用效率低。研究认为,沙蒿通过对土壤干旱和高温的忍耐机制而保持长时间较高的光能利用效率,并在土壤湿润时迅速提高光合能力和积累干物质来适应半干旱的沙地环境,而且依靠高蒸腾速率和强的水分吸收能力来竞争性抑制其他植物的生长。     

土地利用方式对喀斯特地区环境小气候日动态的影响

2007年6月,通过典型样地观测,研究了广西凌云县典型喀斯特地区5种不同土地利用方式下光照强度、气温、空气相对湿度、土壤温度、表层（0～5 cm土层）土壤含水量的日动态.结果表明：不同土地利用方式改变了地上植被的组成、覆盖度和高度,进而改变了环境小气候,研究区不同土地利用方式的小气候质量依次为林地＞灌林＞草地＞农耕地＞石漠化裸地; 石漠化裸地光照强度较强、气温和土壤温度较高、空气相对湿度和土壤含水量较低,且各因子的变幅均较大,样地环境趋于干热化;与石漠化裸地相比,林地、灌林地、草地和农耕地内的光照强度分别下降96.4%、52.0%、17.0%和44.2%,气温分别下降30.1%、20.2%、12.7%和17.8%,空气相对湿度分别提高129.2%、57.2%、18.0%和41.2%,土壤温度分别下降11.5%、8%、2.5%和5.5%,表层土壤含水量分别提高42.6%、33.2%、15.7%和14.0%,林地与灌林地各因子的变幅相对趋缓,样地环境趋于凉湿化.各样地光照强度、气温和土壤温度之间呈正相关,三者均与空气相对湿度、土壤含水量呈负相关,空气相对湿度与表层土壤含水量呈正相关.     

新疆农田作物覆膜地温极值的时空变化

土壤温度的上限和下限值极大地影响农田作物的生长发育．根据对新疆农田2年度不同观测时刻、不同覆膜条件及不同作物的最高和最低地温的分析,可知2年度全生育期地温极值均发生在0cm位置．地温极值依观测时刻的不同而变动．覆膜最低温度始终高于裸地,说明覆膜对提高低温段土壤温度有明显作用．最低温度的日变化可用二次函数表达;14：00和20：00时最高地温可分别用深度的椭圆曲线和线性关系表达．不同条件下的地温极值和气温具有线性关系,其中裸地最低温度与气温的相关性高于覆膜;玉米最低温度与气温的相关性高于棉花;最高温度与气温的相关性比最低温度与气温的相关性差．     

Photosynthesis, Transpiration, Leaf Temperature, and Stomatal Activity of Cotton Plants under Varying Water Potentials

Cotton plants, Gossypium hirsutum L. were grown in a growth room under incident radiation levels of 65, 35, and 17 Langleys per hour to determine the effects of vapor pressure deficits (VPD's) of 2, 9, and 17 mm Hg at high soil water potential, and the effects of decreasing soil water potential and reirrigation on transpiration, leaf temperature, stomatal activity, photosynthesis, and respiration at a VPD of 9 mm Hg.

Transpiration was positively correlated with radiation level, air VPD and soil water potential. Reirrigation following stress led to slow recovery, which may be related to root damage occurring during stress. Leaf water potential decreased with, but not as fast as, soil water potential.

Leaf temperature was usually positively correlated with light intensity and negatively correlated with transpiration, air VPD, and soil water. At high soil water, leaf temperatures ranged from a fraction of 1 to a few degrees above ambient, except at medium and low light and a VPD of 19 mm Hg when they were slightly below ambient, probably because of increased transpirational cooling. During low soil water leaf temperatures as high as 3.4° above ambient were recorded. Reirrigation reduced leaf temperature before appreciably increasing transpiration. The upper leaf surface tended to be warmer than the lower at the beginning of the day and when soil water was adequate; otherwise there was little difference or the lower surface was warmer. This pattern seemed to reflect transpiration cooling and leaf position effects.

Although stomata were more numerous in the lower than the upper epidermis, most of the time a greater percentage of the upper were open. With sufficient soil water present, stomata opened with light and closed with darkness. Fewer stomata opened under low than high light intensity and under even moderate, as compared with high soil water. It required several days following reirrigation for stomata to regain original activity levels.

Apparent photosynthesis of cotton leaves occasionally oscillated with variable amplitude and frequency. When soil water was adequate, photosynthesis was nearly proportional to light intensity, with some indication of higher rates at higher VPD's. As soil water decreased, photosynthesis first increased and then markedly decreased. Following reirrigation, photosynthesis rapidly recovered.

Respiration was slowed moderately by decreasing soil water but increased before watering. Respiration slowed with increasing leaf age only on leaves that were previously under high light intensity.

     

羊草叶片气体交换参数对温度和土壤水分的响应

 采用生长箱控制的方法研究了羊草(Leymus chinensis)幼苗叶片光合参数对5个温度和5个水分梯度的响应和适应。结果表明：轻度、中度土壤干旱并没有限制羊草叶片的生长,对气体交换参数亦无显著影响,反映了羊草幼苗对土壤水分胁迫的较高耐性。叶片生物量以26 ℃时最大,其它依次为23 ℃、20 ℃、29 ℃和32 ℃。温度升高使气孔导度和蒸腾速率增加, 却使光合速率和水分利用效率降低。水分和温度对叶片生物量、光合速率、气孔导度和蒸腾速率存在显著的交互作用,表明高温加强了干旱对叶片生长和气体交换的影响, 降低了羊草对土壤干旱的适应能力。高温和干旱的交互作用将显著减少我国半干旱地区草原的羊草生产力。     

Interaction Effects of Light,Temperature and Nutrient Limitations (N,P and Si) on Growth,Stoichiometry and Photosynthetic Parameters of the Cold-Water Diatom Chaetoceros wighamii

Light (20-450 μmol photons m^-2 s^-1), temperature (3-11°C) and inorganic nutrient composition (nutrient replete and N, P and Si limitation) were manipulated to study their combined influence on growth, stoichiometry (C:N:P:Chl a) and primary production of the cold water diatom Chaetoceros wighamii. During exponential growth, the maximum growth rate (~0.8 d^-1) was observed at high temperture and light; at 3°C the growth rate was ~30% lower under similar light conditions. The interaction effect of light and temperature were clearly visible from growth and cellular stoichiometry. The average C:N:P molar ratio was 80:13:1 during exponential growth, but the range, due to different light acclimation, was widest at the lowest temperature, reaching very low C:P (~50) and N:P ratios (~8) at low light and temperature. The C:Chl a ratio had also a wider range at the lowest temperature during exponential growth, ranging 16-48 (weight ratio) at 3°C compared with 17-33 at 11°C. During exponential growth, there was no clear trend in the Chl a normalized, initial slope (α*) of the photosynthesis-irradiance (PE) curve, but the maximum photosynthetic production (P_m) was highest for cultures acclimated to the highest light and temperature. During the stationary growth phase, the stoichiometric relationship depended on the limiting nutrient, but with generally increasing C:N:P ratio. The average photosynthetic quotient (PQ) during exponential growth was 1.26 but decreased to <1 under nutrient and light limitation, probably due to photorespiration. The results clearly demonstrate that there are interaction effects between light, temperature and nutrient limitation, and the data suggests greater variability of key parameters at low temperature. Understanding these dynamics will be important for improving models of aquatic primary production and biogeochemical cycles in a warming climate.     

Effect of air and soil temperature on water balance of jojoba growing under controlled conditions

Jojoba [ Simmondsia chinensis (Link) Schneider] cuttings were grown in pots under constant light intensity and vapour pressure deficit at wir temperatures of 18 and 27°C in climate-controlled cabinets. Leaf conductance and transpiration rate decreased exponentially as the xylen water potential (Ψ_x) decreased concurrently with the drying out of the soil. At high Ψ_x'leaf conductance and transpiration rate were much higher at the higher air temperature, and as Ψ_x declined both parameters decreased more rapidly at 27°C than at 18°C. When soil temperatures were decreased from 27 to 13°C, leaf water potential was not affected at either air temperatures, but transpiration rate was reduced. A linear negative correlation was found between transpiration rates and soil temperatures. It is suggested that the low soil temperature may restrict reducion of water flux in turn reduces stomatal conductance and transpiration without affecting the water potential in the shoot. The releavance of the response to changes in soil or air temperature to the performance of the plant in its semi-arid habitat is discussed.     

Transpiration as a function of soil temperature and soil water stress

An apparatus was developed for the measurement of transpiration rates of Trifolium repens. The transpiration rates were measured under controlled conditions of soil water stress and soil temperature. Other environmental parameters such as air temperature, relative humidity, light intensity and air speed were held constant. Diffusive resistances were calculated and stomatal aperture changes were recorded for all treatment combinations. A significant interaction between soil water stress and soil temperature was observed for stomatal closures. Stomatal closure was observed even in the so-called wet range of soil water stress. An increase in mesophyll resistance or incipient drying was observed for several treatment combinations. The mesophyll resistance was shown to increase as soil water stress increased.     

不同培养条件下差巴嘎蒿种子萌发与幼苗生长特征

差巴嘎蒿是科尔沁沙地流动、半流动沙丘的主要物种之一.本试验设置室内自然条件培养、培养箱中恒温全光(24 h光照)培养、恒温光暗交替(12 h光照)培养和恒温全暗(0 h光照)培养4种处理,研究不同温度和光照对差巴嘎蒿种子萌发及幼苗生长的影响.结果表明： 室内自然光照和温度条件下差巴嘎蒿种子的萌发率(66.6%)和萌发指数(19.1%)均明显低于恒温箱培养,恒温箱的3个处理中,全暗条件下的种子发芽率(70.2%)低于全光(73.4%)和光暗交替(73.4%)培养,但差异不显著,全光条件下的萌发指数为28.2%,显著低于全暗(31.4%)和光暗交替(30.8%)培养;光照条件对幼苗生长的影响明显,在种子萌发过程中,胚根的生长出现全光促进、全暗抑制的现象,胚芽长度为全暗(2.81 cm)和光暗交替(1.51 cm)条件下高于全光(1.21 cm)培养和实验室自然条件(1.27 cm)培养.环境温度可能是限制差巴嘎蒿种子萌发的主要因素,而光照是影响差巴嘎蒿幼苗生长发育的重要因子.     

Radiation and soil temperature interactions on the growth and physiology of eastern white pine ( Pinus strobus L.) seedlings

A greenhouse experiment was set up during one growing season to test the hypothesis that soil temperature controls a significant part of the light response of eastern white pine (Pinus strobus L.) seedlings that is observed in the field. The experimental design was a three by three factorial split-plot design, with three levels of light availability: 10%, 40% and 80% of full light; and three levels of soil temperature: 16 °C, 21 °C, and 26 °C in the soil at midday. The results show significant interactions between light and soil temperature factors on several variables (gas exchange, root growth, leaf-mass ratio and leaf–mass per unit area), but not on shoot dry mass. These interactions indicate that, in the field, a significant proportion of the light response of young eastern white pine could result from changes in soil temperature, especially under conditions of limiting water availability. Our results suggest that soil temperature must be taken explicitly into account as a driving variable when relating the growth of young eastern white pine to photosynthetic radiation.