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1.
为明确黄土高原丘陵区第三副区典型流域-甘肃天水罗玉沟流域刺槐生长过程及其与气候关系随海拔变化的规律。利用树木年代学方法分别建立高、中、低3个海拔刺槐的标准年表,并分析不同海拔刺槐径向生长过程以及对气候变化的响应。研究结果表明:(1)中、低海拔刺槐径向生长与温度因素多为负相关,而高海拔刺槐径向生长与温度因素多呈正相关。高海拔刺槐生长与上一年生长季(6月)、休眠期(当年3—4月)和当年生长季(6月)均温、最低温和最高温呈显著正相关,其中受最低温影响最显著;中、低海拔刺槐与上一年生长季和当年生长季的均温、最高温和最低温呈显著负相关,低海拔受均温影响显著。(2)随海拔升高,刺槐径向生长与降水和相对湿度的正相关呈降低趋势。低海拔刺槐生长与上一年生长季(7—9月)和当年生长季(6—9月)降水、相对湿度呈显著正相关,中海拔刺槐与当年生长季(6—9月)降水、相对湿度呈显著正相关,而高海拔刺槐生长与上一年生长季(6—7月)相对湿度呈显著负相关。(3)低海拔刺槐与上一年6月—当年10月帕默尔干旱指数(PDSI)呈显著正相关;中海拔刺槐与上一年6月和当年2—10月PDSI呈显著正相关;高海拔刺槐与上一年6—...  相似文献   

2.
于2017年期间,每日间隔1h自动监测1次,同步测定广州南沙湿地与珠海淇澳红树林林内、林外旷地的气温及大气相对湿度,比较研究不同地点红树林生境的生态效应。结果表明,两地红树林林内气温一直低于林外旷地,相对湿度则高于旷地。南沙红树林日降温最大值6.832℃,平均降温0.733℃,平均降温率3.092%;日增湿最大值23.416%,平均增湿5.528%,平均增湿率6.345%。淇澳红树林日降温最大值6.607℃,平均降温1.722℃,平均降温率7.011%;日增湿度最大值45.044%,平均增湿1.681%,平均增湿率1.942%。两地红树林林内气温年均值比较,南沙比淇澳高0.126℃,林外旷地气温年均值淇澳比南沙高0.862℃;红树林林内湿度年均值南沙比淇澳高4.427%,林外旷地湿度年均值南沙比淇澳高0.581%。总体上,两地红树林的降温、增湿效应均明显,其中淇澳红树林降温效应更明显,而南沙红树林增湿效应更明显。  相似文献   

3.
甘肃兴隆山马麝呼吸系统疾病流行病初步调查   总被引:6,自引:0,他引:6  
对甘肃省兴隆山国家级自然保护区马麝人工驯养场马麝呼吸系统疾病进行了自然概况及饲养管理情况调查、既往流行病学统计、临床症状和病理剖检变化观察、预防和治疗情况调查。结果表明,马麝呼吸系统疾病的流行与当地的温度和湿度(尤其是湿度)密切相关,年平均湿度较高的月份该病的发病率明显高于年平均湿度较低的月份;天气骤冷、阴雨连绵等应激因子可促使本病的发生。  相似文献   

4.
温湿度对稻纵卷叶螟卵的联合作用   总被引:1,自引:0,他引:1  
为了探讨温湿度在稻纵卷叶螟Cnaphalocrocis medinalis (Guenée)种群发展中的作用, 通过室内实验调查了不同温度和湿度组合下该蛾卵的发育历期、 胚胎发育情况、 孵化率和卵粒重量的变化。结果表明: 在相同温度下卵历期随相对湿度的增大而缩短, 孵化率随相对湿度的加大而提高。在22℃下低于46%的相对湿度显著降低了卵的孵化率, 而在25~34℃下低于66%的相对湿度会引起孵化率的显著降低, 37℃下卵无论在何种湿度中均不能孵化。在50%左右的低湿条件下, 温度高于28℃后卵也不能孵化。温度在22~31℃和相对湿度在77%~100%范围内, 卵的孵化率无显著差异, 这属于稻纵卷叶螟卵的适宜温湿度范围。稻纵卷叶螟卵的发育起点温度和有效积温分别为10.1±0.6℃和63.7±3.5日度。卵的孵化率(Y)与温湿系数(RH/T)间呈显著的逻辑斯蒂曲线关系Y=0.8662/[1+exp(17.4084-7.5714×RH/T)]。温湿系数在2.34以下时卵孵化率将低于50%, 而达到3.0左右时孵化率接近最高值。结论认为, 低湿造成的稻纵卷叶螟卵重量显著降低、 卵粒干瘪、 胚胎发育受阻是致死卵的主要原因。  相似文献   

5.
陆面碳循环在气候变化和生态系统碳收支平衡中起到关键作用。水热变化与CO2交换分析对于深刻揭示荒漠生态系统的区域碳循环规律及机制具有重要意义。本研究选取科尔沁沙地典型流动沙丘为对象,利用涡度相关技术和波文比气象观测系统所测的数据分析近地层水热变化及CO2交换特征,探讨了日和季节尺度,以及0~10 m垂直空间尺度下流动沙丘近地层温湿度与CO2交换过程的相互关系。结果表明: 研究区近地表气温垂直变幅在0.4~2 ℃,4—9月,气温随着高度的升高呈减的趋势,其余月份则相反,空气相对湿度季节变幅超过40%;在2018年生长季,沙丘净生态系统碳交换量(NEE)的日均值为-0.02 mg·m-2·s-1,全年水平的NEE日均值为0.003 mg·m-2·s-1,全年整体上表现为碳源;垂直空间尺度上,垂直温、湿度差与NEE拟合均较好,水热影响拐点分别为10%和0.5 ℃,而全年尺度上温度拟合结果相对较好,水热影响拐点分别为17 ℃和65%。在生长季,研究区近地层垂直温差为负,会抑制流动沙丘对大气CO2的吸收,而大气高湿环境则会促进流动沙丘对大气CO2的吸收。不同时间和不同垂直高度上,水热变化与CO2交换关系较密切,对沙丘碳汇和碳源的产生具有一定的影响,且碳收支对温度的敏感性强于相对湿度。  相似文献   

6.
The aim of the present investigation was to determine the impact of relative humidity (RH) and temperature on conidial germination, nuclear position and effect of important fungicides on growth and conidial germination of Cercospora canescens. Germination of conidia was observed at RH range 92–100% at 5–35°C. Significant interaction between temperature and RH indicated that higher humidity and high temperature promoted quick germination both in the presence and absence of free moisture. Although in absence of free moisture at 92–95% RH higher temperatures 25–35°C promoted quick evaporation of moisture and no conidial germination. Number of germtube was increased significantly at the optimum temperature 25–30°C and higher humidity (98–100%). But higher temperature 25–35°C with lower RH did not support the conidial germination. This finding is very important for disease forecasting using meteorological data. The spray of Carbendazim as contact fungicide may not be useful since it is not effective against the conidia of C. canescens. Triadimefon did not inhibit the conidia germination but completely inhibited mycelium development at 50 μg/ml. Propriconazole inhibited both conidia germination and mycelial development. Therefore, Propiconazole may be taken as protective as well as curative spray. In non-systemic fungicide, Copper oxychloride gave anticipated result by inhibiting both conidial germination and mycelium development. Therefore, copper oxychloride can be used as protectant fungicides for Cercospora leaf spot caused by C. canescens.  相似文献   

7.
Robert C. Beason 《Oecologia》1978,32(2):153-169
Summary Radar and visual observations were made on water bird migration throuh the Southwest at six stations from February 1973 through November 1974. The influence of weather on nocturnal non-passerine migration in the Southwest is less significant than reported for passerine migration elsewhere. Both seasonality and weather factors influence water bird migration, but the relative contribution of each is strongly dependent on the specific migration season. Spring migration, which has more extreme weather conditions, shows a stronger correlation to meteorological factors. Autumn migration in the Southwest rarely experiences severe weather, and consequently shows a stronger correlation to seasonality than to weather.The intensity of spring non-passerine migration was highly correlated with height of freezing level, temperature at sunset and midnight, humidity at sunset, cloud height at sunset and midnight, following winds aloft, and inversely related to change in temperature and day of the year. The most important variables listed by the stepwise linear multiple regression analysis were freezing level, following winds aloft, day of the year, and surface wind speed. When the height of the lowest cloud layer was allowed to enter the regression analysis, freezing level and cloud height were the most significant variables, with the intensity of migration higher with higher freezing level and higher cloud base. The most important variables predicting the occurrence or absence of migration were freezing level, barometric pressure and dew point.Autumn water bird migration was most highly correlated with cloud height and day of the year, and inversely correlated with humidity. The most important variables from the stepwise regression analysis and discriminant function analysis were day of the year, 670 m following-wind speed, and temperature. When cloud height was allowed to enter the model, it was the only significant factor influencing migration. As in spring, higher rates of autumn migration occurred with higher freezing levels.More migration occurred on the Great Plains than in the Rocky Mountains; but within the mountains, geography had little influence on the intensity of migration. Indirect evidence indicates that waterfowl and shorebirds move over the mountains (up to 2000 m above the surrounding terrain and 3500 m above sea level), rather than around them.  相似文献   

8.
Multivariate statistical methods were used to elucidate which environmental factors influence the activity patterns of free-living Malayan pit vipers, Calloselasma rhodostoma. Fourteen adult snakes were implanted with miniature radiotransmitters and located a total of 887 times in 5 months. The pit vipers usually remained coiled on the ground for several consecutive days before moving at night to a new site. Partial correlation tests revealed that the frequency and distance of movements to new sites by tagged snakes were highly positively correlated with ambient relative humidity, but not with rainfall, ambient temperature or the lunar cycle. This finding was corroborated by the frequency with which active non-tagged C. rhodostoma were encountered at night, In each site, the proportion of the snakes' bodies exposed to view was positively correlated with ambient humidity, and the snakes retreated to areas with deeper undergrowth when ambient humidity was low. Overt thermoregulatory behaviour was not observed, and implanted thermosensitive transmitters revealed that the snakes were passive thermoconformers.
These findings seem lo contradict much of the current literature which shows temperature to be the dominant abiotic factor affecting reptilian activity, but most herpetologists have considered only temperate forms. Ambient temperature in our tropical study site was warm and relatively constant throughout the year (mean daily range = 24- 33°C), so the pit vipers could passively maintain body temperature within a fairly narrow range, with a daytime mean of 29.4°C. Ambient relative humidity, on the other hand, was very variable, and confining exposure and activity to periods of high ambient humidity may be necessary to avoid dehydration  相似文献   

9.
李猛  段文标  陈立新 《应用生态学报》2009,20(12):2853-2860
以小兴安岭原始红松阔叶混交林林隙为研究对象,通过对林隙内光量子通量密度(PPFD)、气温和空气相对湿度进行连续观测,比较其间的时空分布格局.结果表明:晴天和阴天阔叶红松林林隙的PPFD日最大值均出现在11:00—13:00,晴天林隙内各个时段最大值出现位置不同,日最大值出现在林隙北侧林冠边缘处;而阴天各个时段最大值均处于林隙的中心.林隙内月平均PPFD 为6月最高、9月最低,极差7月最大.林隙内晴天气温的峰值出现在9:00—15:00,而阴天气温峰值在15:00—19:00,均位于林隙中心南8 m.5:00—9:00林隙各点阴天的气温都高于晴天,9:00—19:00则相反.月平均气温为6月最高、9月最低.晴天和阴天空气相对湿度的峰值均出现在5:00—9:00,日最大值在林隙西侧林冠边缘处,且阴天的相对湿度始终大于晴天.月平均相对湿度为7月最高、6月最低.晴天PPFD的异质性大于阴天,而气温和相对湿度的异质性则不明显.生长季内不同月份PPFD、气温和空气相对湿度的最大值所处位置不同.PPFD和气温的月均值在林隙中心及附近变化梯度较大,而相对湿度的月均值则在林隙边缘变化梯度较大.  相似文献   

10.
城市河道绿带宽度对空气温湿度的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
以北京市北五环清河旁侧8段不同宽度的绿带为研究对象, 分别对样地和对照样地的气温和相对湿度进行同步测定, 每2 h测定一次, 每个季节连续测定7天。结果显示: 绿带在春、夏、秋季具有增湿降温效应, 并且此效应随着绿带宽度的增加而不断增强, 夏季的增湿降温效应最强, 春、秋季节的增湿降温效应差别不大; 绿带在冬季具有保温增湿效应, 随着绿带宽度的增加, 保温效应不断增强, 增湿效应不断减弱。四季中, 绿带温湿度变化受环境温度的影响较大, 在一天中的14:00-16:00时段, 春、夏、秋季增湿降温效应最强; 在此时段冬季的保温效应最弱, 增湿效应最强。  相似文献   

11.
气候变暖背景下杉木年轮密度对气候因子的响应   总被引:1,自引:0,他引:1  
为探讨杉木年轮密度与气候因子的响应关系,采用树木年轮学方法,以60年生杉木种源林为研究对象,测定杉木整轮密度、早材密度、晚材密度、晚材最大密度和早材最小密度,分析在气候变暖条件下主要气候因子(温度、降水、相对湿度)对杉木年轮密度及其生长的影响。结果表明:杉木不同年轮密度指标均受到温度、降水和相对湿度的显著影响。早材密度与当年夏季最高温度、当年5月降水量,最大密度与当年10月、当年秋季降水量,最小密度与前一年秋季降水量、最小相对湿度呈显著负相关。滑动相关分析表明气候因子在短时间尺度上对杉木生长影响的稳定性有显著影响,其中杉木年轮最大密度与当年10月、秋季的平均相对湿度和最小相对湿度,最小密度与当年2、3月的平均相对湿度和前一年秋季的平均相对湿度、最小相对湿度、降水量的负相关关系最为稳定。杉木年轮最小密度对前一年气候要素的响应存在滞后效应,且晚材密度对当年春季的气候要素响应也存在滞后效应。研究结果对开展亚热带针叶树种年轮生态学和年轮气候学研究具有重要参考价值,建议选择武夷山的天然林获取更长年表用于重建古气候。  相似文献   

12.
Effect of air temperature and humidity on ingestive behaviour of sheep   总被引:3,自引:0,他引:3  
Thirty-two Polwarth ewes, of ages up to 1 year, were observed in a climatic chamber (24 to 45° C) for eight periods of 5 h each. The observations were made through a window in the chamber wall. All animals were observed four times, then shorn and observed four times again. The animals were given weighed quantities of water and feed consisting of commercial concentrate plus Rhodes grass (Chloris gayana) hay. The water and feed remaining after 5 h of observation were weighed. The following traits were analysed: time eating hay (TEH), time eating concentrate (TEC), time drinking water (TDW), weight of hay eaten (WHE), weight of concentrate eaten (WCE), volume of ingested water (VIW), ruminating time standing up (RTS), ruminating time lying down (RTL), idling time standing up (ITS), and idling time lying down (ITL). Shearing had a significant effect for all traits except ITS. Shearing resulted in higher values for all traits except for ITS and ITL. Ingestion of hay (TEH and WHE) decreased with increased air temperature and humidity, while the ingestion of concentrate (TEC) and WHE) and water (TDW and VIW) increased. Rumination decreased with increased air temperature and humidity, and was higher in shorn than in unshorn sheep.  相似文献   

13.
Effect of Temperature on Survival of Airborne Mycoplasma pneumoniae   总被引:2,自引:0,他引:2       下载免费PDF全文
Aerosols of Mycoplasma pneumoniae were prepared at each of eight relative humidities between 0 and 85% and at five separate temperatures between 10 and 43 C. Survival of these organisms was found to be a function of both relative humidity and temperature. However, the temperature response was mediated by humidity in that the effects of temperature could be observed only if some water vapor was present. At all temperatures, survival of M. pneumoniae in aerosols was found to be best at the extremes of relative humidity. The effects of temperature were such that irrespective of relative humidity an increase in temperature resulted in a decreased airborne survival time.  相似文献   

14.
以庐山自然保护区3个不同海拔样地采集的138根日本柳杉样芯为研究材料,利用树木年轮学方法分析其径向生长与季节和月气候因子的响应关系。结果表明:低海拔处日本柳杉径向生长对气候因子的响应相比于中、高海拔更敏感;中、低海拔径向生长与春季相对湿度呈显著正相关(P<0.05),低海拔径向生长与春季日照时数、夏季均温呈显著负相关(P<0.05),而中海拔径向生长与夏、秋季均温呈显著负相关(P<0.05);高海拔径向生长与各个季节气候因子表现出一定的相关性,但相关性不显著; 3个海拔径向生长均与当年1月均温呈显著正相关(P<0.05),中、低海拔径向生长与上年7月及当年7月均温呈显著负相关(P<0.05),高温会抑制树木的生长,低海拔径向生长与当年4月空气相对湿度、降水量呈显著正相关(P<0.05),与当年4月日照时数呈显著负相关(P<0.05),随海拔的升高相关性降低;庐山日本柳杉径向生长与主要气候要素之间的相关性呈现出明显的季节性,日本柳杉径向生长主要受上年7及7月均温和4月空气相对湿度的影响,海拔是影响日本柳杉径向生长对气候因子响应的重要因素,最终建立...  相似文献   

15.
温、湿度对美洲斑潜蝇发育、存活及食量的影响   总被引:6,自引:0,他引:6  
郝树广  康乐 《昆虫学报》2001,44(3):332-336
以花斑芸豆Phaseolus vulgaris为食料植物,在不同温、湿度组合下,观测了美洲斑潜蝇Liriomyza sativae的发育、存活及取食特征。结果表明,卵、幼虫和蛹期的发育速率与温度的关系均呈S型曲线。发育起点温度为:卵,8.9℃;幼虫, 10.1℃;蛹,9.6℃;整个未成熟期,9.5℃。有效积温为:卵,57.7日·度;幼虫,53.9日·度;蛹,151.9日·度;整个未成熟期,264.2日·度。湿度对发育速率的影响不明显。温度对存活的影响较大,当温度>34℃或<19℃时,各虫态的存活率都显著降低。湿度对存活率的影响主要发生在蛹期,当湿度低于50%时,蛹的羽化率显著降低。在高温、低湿的条件下,蛹不能羽化。在相对低温下的累计取食面积大于高温时的相应值,在25℃时达到1.6 cm2,而在28℃及以上温度时取食面积只有0.9 cm2左右。  相似文献   

16.
安徽省徽州地区翼手类及其越冬生态的初步观察   总被引:4,自引:1,他引:4  
关于安徽省的翼手类,G. M. Allen(1938)、王岐山等(1966),黄文儿等(1978)、徐亚君等(1982)均有过报道,共记录了21种,分属菊头蝠科、蹄蝠科、蝙蝠科和犬吻蝠科,计4科11属。梁仁济等(1982)曾对皖南冬眠前蝙蝠的几项生理指标作过测定分析,但尚未见到有关蝙蝠自然越冬生态的专题报道。我们于1981年10月-1982年5月,1982年10月-1983年4月,对徽州地区的31个蝙蝠越冬岩洞作了采集和观测。并选定了休宁县临溪、歙县王村和屯溪市三处共7个岩洞和一个市郊居民点作为系统采集观测点,先后进行了84个洞次的采集观测,现将有关材料初报如下。  相似文献   

17.
The paper deals with the variations in the toxicity of 2,4-D to Cyprinus carpio at different temperatures during different seasons of the year. The higher temperature has higher toxicity and vice versa at the same concentration. The TLm values indicate that there is a 7–7.5 fold increase in toxicity with the rise in temperature from 17°C in February (winter) to 39°C in May (summer). These results have significance in manipulating the 2,4-D doses for the eradication of aquatic weeds in different seasons.  相似文献   

18.
在同一湿度(53%RH)不同温度(14℃、17℃、20℃、23℃、26℃、29℃、32℃、35℃及同一温度(26℃)不同湿度(30%RH、53%RH、75.5%RH、85%RH、92.5%RH、100%RH)组合条件下,测定了温湿度对番茄刺皮瘿螨Aculops lycopersici (Massee)生长发育及繁殖的影响。结果表明,温、湿度对该螨存活率有明显影响,以23℃(53%RH)和75.5%RH(26℃)条件下最高,分别为89.9%和87.1%; 其发育历期较短,在14~35℃和30%~100%RH范围内,历期随温度升高而缩短,随湿度升高而延长; 番茄刺皮瘿螨的发育起点温度较高,卵、若螨和整个世代的发育起点温度分别为10.51、9.02和9.15℃。完成一代需要105.56日·度。温湿度对番茄刺皮瘿螨的繁殖力有明显影响,产卵期随温度升高而缩短,随湿度升高而延长; 产卵量在26℃(53%RH)和53%RH(26℃)下最高,每头雌虫产卵分别为44.3粒和42.2粒; 26℃(53%RH)和53%RH(26℃)条件下种群的内禀增长率最高,分别为0.2645和0.2669。结果表明,适宜的温湿度条件为温度26~29℃、相对湿度53%~75%。  相似文献   

19.
本文报道了小地考虑蛾迁飞活动与气候因子能源物质的相互关系。1985-1988年在云南白马雪山进行了三个全年的小地考虑蛾迁飞动态的系统观察,并测定比较了不同虫源的脂肪含量。结果表明,白马雪山一年有5次迁飞蛾峰。迁飞蛾种群动态与温度、湿度、降水、风速、气压和高空50000帕的西南及北风气流有密切关系。不同虫源的雌蛾脂肪含量差异显著,迁出型含量最高,本地型次之,迁飞过境型又次于前者,迁入型含量最低。  相似文献   

20.
在祁连山东部西营河流域不同海拔采集年轮样品,利用树木年代学方法建立高海拔(3000 m)、中海拔(2750 m)、低海拔(2500 m)青海云杉标准化年表,将年轮宽度指数与不同时段气温和降水分别进行相关分析,研究祁连山东部不同海拔青海云杉径向生长对气候变暖的响应。结果表明: 水热是祁连山东部青海云杉径向生长的主要限制因子,不同海拔树木的生长限制因子基本一致。在显著升温之前(1961—1986年),低、中、高海拔3个样点的青海云杉径向生长均与上一年7—8月和当年8月平均最高温呈显著负相关,与当年6月相对湿度呈显著正相关。显著升温之后(1986—2014年),高、中、低海拔树木生长与气温仍呈显著负相关,而与当年2月的相对湿度由升温前的不显著负相关转为显著正相关,与6月降水和相对湿度由升温前的显著正相关转为不显著的负相关。升温导致祁连山东部各海拔青海云杉树轮生长变慢,其中高海拔所受影响最大。气候变暖导致的干旱胁迫可能是青海云杉径向生长发生变化的主要原因。  相似文献   

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