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1.
The noctural activities of the phenotypic shell colour morphy and age classes (adults and juveniles) of Arianta arbustorum were recorded 1 day week-1 for 4 weeks in several laboratory microclimatic conditions. Six constant temperatures between 3 and 18C and four levels of relative humidities between 34 and 98% were maintained. A light regime of 16 h light: 8 h dark was used. There are highly significant differences in activity at different levels of adaptation temperature and relative humidity. The interaction between these factors is significant. There are no significant differences in nocturnal activity between the two phenotypic shell colours nor between the two age classes, but the interaction between morph and relative humidity is significant. The interaction between age classes and relative humidity is also significant. Yellows are more active than browns at high humidities, but less active at low. They are therefore likely to be behaviourally more responsive than browns in an environment of fluctuating humidities. This result is discussed in relation to the maintenance of the polymorphism.  相似文献   

2.
运用Granier热扩散式探针法,于2010年干湿季对鼎湖山自然保护区针阔混交林4种优势树种马尾松、锥栗、木荷和广东润楠的树干液流密度进行连续监测,并同步观测气温、相对湿度和光合有效辐射等环境因子的变化,研究其树干液流特征及其对环境因子的响应.结果表明:在干湿季,4种优势树种的树干液流速率日变化均呈“昼高夜低”的典型单峰曲线,阔叶树锥栗、木荷和广东润楠的平均液流速率和峰值以及日液流量均显著大于针叶树马尾松;马尾松、锥栗、木荷和广东润楠的最大树干液流密度分别为29.48、38.54、51.67、58.32g H2O·m-2·s-1.优势树种树干液流速率的变化与环境因子的昼夜变化存在时滞;液流速率变化与光合有效辐射、水汽压亏缺和气温等环境因子的变化呈显著正相关,其中湿季以光合有效辐射为主导因子,干季以气温为主导因子.  相似文献   

3.
夏季城市河流宽度对绿地温湿效益的影响   总被引:2,自引:0,他引:2  
城市河流是城市生态系统中重要的组成部分,对城市生态环境的改善发挥着重要作用.利用小尺度定量测定的技术方法,分析了北京市三环至五环附近7条不同宽度城市河流对其旁侧绿地温湿效益的影响.结果表明: 城市河流宽度是影响绿地温湿效应的重要因素.当河流宽度为8 m时,绿地具有一定的增湿效应,但降温效果不明显;当河流宽度为14~33 m时,绿地降温、增湿效果明显;当河流宽度超过40 m时,绿地降温、增湿效果显著且趋于稳定.7条河流旁侧绿地与各自对照间的温、湿度差异均达到显著水平,且显著发挥温湿效益的河流宽度为44 m.河流旁侧绿地夏季温度(x)、湿度(y)关系的回归方程为y=173.191-3.247x,相对湿度每升高1.0%,温度降低约0.3 ℃.  相似文献   

4.
The effects of temperature and humidity on the emergence patterns of diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), were studied at four temperatures (20, 25, 28, and 33 degrees C),three relative humidities (50, 70, and 90%) and a photoperiod of 14:10 (L:D) h. Both sexes emerged primarily in the late afternoon to early morning, and the peaks of emergence varied depending on temperature and humidity. Females emerged significantly earlier than males. Incubation at 33 degrees C and 90% RH had a significant effect on the emergence rate, but no significant interaction was found between temperature and humidity. Emergence duration was 25.3 h for both sexes at 90% RH, with emergence duration at 33 degrees C lower than the other treatments. The sex ratios of diamondback moth under different temperature and humidity treatments were approximately 1:1, and there were no significant effects of temperature and humidity or interactions between these two factors.  相似文献   

5.
Mean skin temperature (Tsk) was measured in 24 subjects during experiments in a climatic chamber. Three conditions of ambient temperature (Ta = 25.6 degrees, 28.9 degrees and 32.2 degrees C), and three of humidity (relative humidity = 50%, 70% and 90%) were studied. A relationship was established by a linear regression technique. It is valid in the 24 degree-34 degree C range, for air velocity = 0.2 m.s-1, clothing insulation = 0.077 degrees C.m2.w-1 (0.5 clo), metabolic rate = 64 w.m-2 (1.1 met) and radiant temperature = air temperature. In these conditions Tsk = 28.125 + 0.021 Pw + 0.210 Ta (Pw: ambient water vapour pressure in mb). It shows a small humidity influence. The influences of sex, transition from one condition to the next, and air velocity were also studied. Measurements in Africa confirmed the small influence of humidity. Ethnic life-style differences indicated that a high precision in Tsk determination is difficult to achieve.  相似文献   

6.
The heat resistance to hot air of spores of Bacillus cereus (ATCC 14579) attached to carriers of stainless steel or silicone rubber was investigated in a range from 1% to 100% relative humidity (RH). Apart from an initial stage, linear survivor curves were obtained for all relative humidities. Neither the attachment itself nor the material of the carrier had an influence on the resistance. A distinct maximum of heat resistance was found at 40% RH. At 122°C the rate constants at 40% RH were five orders of magnitude smaller than at 100% RH and two orders of magnitude smaller than at 1% RH. At relative humidities of more than 40% the rate constants were strongly temperature dependent, whereas at lower relative humidities they were less temperature dependent. No significant influence of the relative humidity on the Arrhenius activation energy was found within each humidity range. The mean values were 295 kJ mol-1 for relative humidities of 60% to 100% RH and 165 kJ mol-1 for 1% to 20% RH. The occurrence of a maximum is ascribed to the existence of two inactivation mechanisms, the first is retarded and the second is accelerated by a reduction of relative humidity. It is assumed that the first mechanism is a protein denaturation. The second mechanism may be an oxidative process.  相似文献   

7.
Summary Changes in the stem diameter of well-watered seedlings of Norway spruce [Picea abies (L.) Karst.] in a climate chamber were registered using laser technique. Pronounced, reversible changes in stem diameter (maximum 80 m) occurred in connection with shifts between dark and light (280 W/m2) conditions. Diurnal variation in stem diameter (50 m) continued unchanged, in terms of amplitude and phase, after the entire needle mass had been removed. It was found that nearly all of the diurnal variation in stem diameter was caused by changes in relative air humidity at the stem surface. The relationship between stem diameter change and relative air humidity was investigated at three temperatures (5, 15, and 25° C) over a range (40–95%) of relative humidities. In addition, the effect of altering the air temperature (range: 5–25°C) on stem diameter change at a constant relative air humidity (85%) was studied.  相似文献   

8.
苹果果面日最高温与主要气象因子的关系   总被引:11,自引:3,他引:8  
一天中 ,苹果果实表面最高温度与气温、日照、相对湿度和风速有着密切的关系。通过生长季自动监测果实表面温度的变化 ,并与设置在监测树旁边气象记录仪数据对比 ,揭示出树冠西南部果实表面温度与气温、日照、相对湿度和风速呈高度相关。结果还表明 :日照和气温是导致果实表面高温 (>45℃ )的两个主要因子。在大多数情况下 ,这两个因子相互作用决定果实高温是否发生 ,但气温的作用更为重要。一般在晴天 ,树冠西南部果实表面高温通常出现在 1 3 :3 0~ 1 5 :5 0。果实达到临界日烧高温 (>45℃ )的综合气象条件是 (1 0 :0 0~ 1 6 :0 0平均值 ) :日照 >5 80 W/m2 ;气温 >3 1 .8℃ ;风速 <1 .0 m/s;相对湿度 <3 0 %。气温、日照、风速和相对湿度与果实表面温度都呈高度相关 ,其多元回归方程为 :果实表面温度 (℃ ) =1 9.7 0 .842×气温 (℃ ) 0 .0 0 989×日照 (W/m2 ) - 2 .0 8×风速 (m/s) - 0 .1 48×相对湿度 (% ) ,r2 =0 .6 97  相似文献   

9.
The mortality of phenotypic shell colour morphs and age classes of the snail Arianta arbustorum in several microclimatic conditions was recorded. An analysis of variance was performed on five factors: adaptation temperature, relative humidity, shell colour, age class and test temperature. There were no significant differences in the mortality between different adaptation temperatures or relative humidities, but the interaction of these two factors was highly significant. There were significant differences in mortality rate between test temperature and age class. The mortality of the brown morph was higher than the yellow one at all adaptation temperatures (overall, P < 0.05). There were no significant differences between the mortality rates of the two morphs at different relative humidities. The mortality of the brown morph was higher than that of the yellow at six out of seven test temperatures. Juvenile snails survived significantly better than adults at all test temperatures.  相似文献   

10.
The mixing and heat transfer phenomena within rotating drum bioreactors (RDBs) used for solid-state fermentation processes are poorly studied. The potential for the establishment of axial temperature gradients within the substrate bed was explored using a heat transfer model. For growth of Aspergillus oryzae on wheat bran within a 24 L RDB with air at a superficial velocity of 0.0023 m s(-1) and 15% relative humidity, the model predicts an axial gradient between the air inlet and outlet of 2 degrees C during rapid growth, compared to experimental axial temperature gradients of between 1 and 4 degrees C. Undesirably high temperatures occur throughout the bed under these operating conditions, but the model predicts that good temperature control can be achieved using humid air (90% relative humidity) at superficial velocities of 1 m s(-1) for a 204 L RDB. For a 2200 L RDB, good temperature control is predicted with superficial velocities as low as 0.4 m s(-1) with the airflow being switched from 90% to 15% relative humidity whenever the temperature at the outlet end of the drum exceeds the optimal temperature for growth. This work suggests that significant axial temperature gradients can arise in those RDBs that lack provision for axial mixing. It is therefore advisable to use angled lifters within RDBs to promote axial mixing.  相似文献   

11.
Cotesia flavipes Cameron (Hymenoptera: Braconidae) is a gregarious larval koinobiont parasitoid of gramineous stemborers from the Indo-Australian region. More recently, it has been introduced into several countries in East and southern Africa for regulation of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae). Establishment has varied from country to country and within country, suggesting that abiotic factors, such as temperature and relative humidity, may influence parasitoid performance. In this work, the effect of temperature and relative humidity on life table parameters of two populations of C. flavipes were measured. The results indicated that the factors and their interactions significantly affected the population growth of C. flavipes. The intrinsic rate of increase of the North Pakistan population of Cotesia flavipes was higher than that of the Indian population at all humidities at 28°C, but there were no differences at other temperatures or humidities.  相似文献   

12.
用PHYTALK植物生理生态监测系统对塔里木河下游英苏断面胡杨的茎流和相关环境因子的日变化进行了监测.结果表明:在极端干旱区塔里木河下游的胡杨茎流日变化表现多峰值,且夜晚仍保持一定流速;主枝与侧枝茎流日变化趋势相似,主枝流速高于侧枝;侧枝对环境变化响应更加灵敏,波动强烈,主枝相对侧枝,茎流变化响应迟钝且有明显滞后效应;茎流变化受太阳辐射、风速和大气温度影响明显,而其它环境因子如空气湿度、土壤湿度等影响则不大,气温与叶温表现出极佳相关性,气温与空气湿度呈显著负相关;同时,日变化中,不同时段起主导作用的因子不尽相同.  相似文献   

13.
We used infrared thermography to study respiratory cooling in the rattlesnakes (Viperidae: Crotalinae) and to partition the effects of air temperature, humidity, and activity levels on head-body temperature differences. We observed a single, cooled region centered around the mouth and nasal capsule that extended across the pit membrane at air temperatures above 20 degrees C. Both head and body temperatures of rattlesnakes increased linearly with air temperature. Head-body temperature differentials also increased with air temperature, but declined significantly at higher relative humidities. Rattling rattlesnakes exhibited significantly greater head-body temperature differentials than did resting rattlesnakes. We suggest that respiratory cooling may provide a thermal buffer for the thermoreceptive pit organs at high air temperatures, but caution that this adaptive hypothesis must be tested with direct neural or behavioral assays.  相似文献   

14.
黄土高原半干旱区侧柏(Platycladus orientalis)树干液流动态   总被引:2,自引:0,他引:2  
应用热扩散式树干茎流计(TDP)于2008年4~10月对黄土高原安塞县侧柏人工林树干液流速率进行了连续测定,并对周围气象、土壤水分等多个环境因子进行了同步测定.结果表明:侧柏在不同月份晴天树干液流速率变化具有明显的昼夜节律性,呈单峰曲线;且各月液流速率日均值受土壤供水水平限制总体上呈下降趋势,即4月份最大,为0.00135 cm · s-1;10月份最小为0.00011cm · s-1;树干液流速率与光合有效辐射、大气温度、水汽压差呈极显著正相关,与相对湿度呈负相关,其相关程度:光合有效辐射>水汽压差>大气温度>相对湿度,并可用线性表达式来估算;侧柏边材面积和地径呈幂指数关系,并以此结合密度估算出样地侧柏人工林的边材面积为4.65m2,最终估算出侧柏人工林生长季总耗水量为1159.6 t · hm-2.  相似文献   

15.
城市湖泊湿地温湿效应——以武汉市为例   总被引:2,自引:0,他引:2  
朱春阳 《生态学报》2015,35(16):5518-5527
选择武汉城市三环内主城区14块湖泊湿地为研究对象,采用小尺度定量测定的方法,研究城市湖泊湿地与温湿效应间的关系。结果表明:(1)城市湿地温度值与面积指数、距离指数呈显著负相关,与景观形状指数呈显著正相关(P0.05);湿度值与面积指数、距离指数、环境类型指数呈显著正相关,与景观形状指数呈显著负相关(P0.05)。其中面积指数的贡献值最大。(2)14块湖泊湿地的降温增湿效应排序为湖泊11—14湖泊6—10湖泊1—5。当湖泊湿地面积为9.2—12.2 hm2时,其降温增湿效应明显;当湖泊湿地面积为308.4hm2左右时,降温效应显著且趋于稳定,湖泊湿地面积为67.6hm2左右时,增湿效应显著且趋于稳定(P0.05)。当湖泊湿地面积达到临界值之后,多斑块离散型(Dispersive)湖泊湿地布局对整个城市环境的降温增湿效应更为显著。  相似文献   

16.
Summary Identified as a dry receptive unit by transitory impulse frequencies up to about 200 imp/sec during rapid drops in humidity (Fig. 3) and which no other modality elicited, the dry unit on the antenna ofPeriplaneta americana is characterized by a regular (Fig. 4) and relatively high stationary impulse frequency (10–65 imp/s). Without exception the stationary discharge rate (tonic frequency) rose with falling values of stationary absolute humidity at constant temperature, and with rising values of stationary temperature of ambient air at constant humidity. Enthalpy and evaporation cooling appear to be ruled out as exclusive adequate explanations for this double dependence. No matter whether tonic frequency is plotted against absolute humidity based on either volume of moist air or weight of dry air, or against partial pressure of water vapor in ambient air, or the difference between saturation and partial vapor pressure, or against relative humidity, the dependence on the temperature is not eliminated (Figs. 5–7). Because a temperature range of about 20 °C and all humidities between 0 and 100% occupy the same large segment of the unit's tonic frequency spectrum (Fig. 8), the unit is termed bimodal.The author wishes to express indebtedness and gratitude to Prof. Dr. Hansjochem Autrum for backing the early stages of this project with the assistance of the Deutsche Forschungsgemeinschaft, to Prof. Dr. Helmut Altner for his prolonged support, to Dr. Hans-Jürgen Hinz for his helpful discussion of questions involving thermodynamics, to Prof. Dr. Friedrich Earth for helpful criticism of the text, and to Miss Christel Praeg for tireless technical assistance.  相似文献   

17.
Salmonella typhimurium survived freeze-drying at a platen temperature of 120 F (48.9 C) and also, though to a much lesser degree, at 160 F (82.6 C). The extent of the survival at these temperatures was dependent on the composition of the model system employed. The incidence of damage immediately after freeze-drying was greater for cells dried at the higher platen temperature and was influenced by the composition of the menstruum in which the cells were dried. In model systems having protein-dominant isotherms, survival during subsequent storage depended greatly on relative humidity, with recovery highest at relative humidities below those corresponding to moisture contents at which a monomolecular layer is formed. In menstrua having a higher sugar content, survival was best at low relative humidities corresponding to a very low equilibrium moisture content in the model system used. Damage during storage tended to be a function of the composition of the gels in which the organisms were freeze-dried, and also depended greatly on the presence of air and on the relative humidity. The maximal percentage of damage usually occurred at the low relative humidities as storage time increased.  相似文献   

18.
Fiberglass duct liners and fiberglass duct boards from eight buildings whose occupants complained of unacceptable or moldy odors in the air were found to be heavily colonized by fungi, particularly by Aspergillus versicolor. Unused fiberglass was found to be susceptible to fungal colonization in environmental chambers dependent upon relative humidity. No colonization was observed at relative humidities below 50%.  相似文献   

19.
Indoor and outdoor airborne bacterialconcentrations were examined in an occupiedoffice building equipped with an airconditioning (HVAC) system, in Tempe, Arizona,USA. A two-stage microbial air sampler wasused to collect bacteria both inside andoutside the office at fixed locations in space,and at regular time intervals from August toDecember, 2000. Simultaneous measurement ofbacterial concentrations, temperature, relativehumidity, light intensity and wind speed wereperformed to explore the effects ofenvironmental factors on bacteria levels. Tengenera and twenty species of airborne bacteriawere found in our samples. AirborneGram-positive bacteria were most abundant, withmore than 90% of the measured population. Theparticle sizes of most outdoor and indoorairborne bacterial aerosols were larger than8.0 μm. According to the measurements ofeither a typical day or three consecutive days,the concentrations of outdoor airborne bacteriawere highest in the morning, but declined inthe afternoon and reached the lowest point inthe evening. With regard to the effects offour environmental factors – temperature,relative humidity, light intensity, and windspeed, the relative humidity had the mostpronounced influence on the outdoor bacterialconcentration, with the number of bacteriaincreasing sharply on a day of high relativehumidity.  相似文献   

20.
近年来山东乳山茶业逐渐兴起, 但由于北方冬春季温度低和倒春寒频繁发生, 茶叶种植面积逐年减小。如何在低成本管理的基础上提高茶叶产量和品质, 成为乳山茶园管理的一大难题。以2007年春季采用水平梯田整地种植的茶园为试验区, 以梯田周围营造的4种网格(8 m × 80 m, 12 m × 80 m, 20 m × 80 m, 40 m × 80 m)茶园防护林为研究对象, 分别在2013年4月、8月和12月, 测定风速、空气温度、土壤温度、空气相对湿度及土壤相对湿度, 以纯茶园作为对照, 进行了小气候因子测定和分析。结果表明: (1) 4种防护林均能有效地降低茶园内风速, 调节气温、土壤温度和土壤相对湿度, 增加空气相对湿度, 为茶树生长提供适宜的生态环境; (2)由于区域水分通量和太阳辐射的季节变化, 4种防护林的小气候调节效应也表现出一定的季节性差异; (3)主成分分析结果表明, 4种茶园防护林中, 影响小气候因子的主要因素是气温和土壤温度, 其因子负荷量分别为-0.978和0.986, 但风速与气温呈极显著相关关系, 与土壤温度之间无显著线性关系, 因此, 风速也能间接地影响林内小气候; (4) 8 m × 80 m的防护林对小气候的总体调节效应优于其他3种防护林。  相似文献   

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