广西岩溶植被演替过程中主要小气候因子日变化特征

选择广西不同气候带下具有典型性和代表性的岩溶区作为研究区域,调查和监测了岩溶植被演替过程中主要小气候因子的日变化特征。结果表明,在石荒漠阶段和草丛阶段,群落光照强、土温和气温高、空气相对湿度低,时间波动比较明显:灌丛阶段群落冠层以下的照度、气温均较低,随时间变化的幅度不大,而冠层以上的光照强度和气温均出现了大幅上升,而且随时间变化的幅度较大;落叶阔叶林阶段和常绿落叶阔叶混交林阶段群落内部的照度、气温及土壤温度均大幅降低,空气相对湿度保持在较大水平,主要小气候因子的时空变化比较平缓。主要小气候因子的时空动态与群落结构和群落种类组成特征密切相关。     

Spatial variability of summer microclimates and plant species response along transects within clearcuts in a beech forest

In a 4383 ha beech forest in central Belgium, we investigated whether, within clearcuts, microclimate gradients are detectable, and we tested for correlations between plant species composition and microclimatic heterogeneity. The results highlight a strong correlation between microclimatic parameters and distance from the forest edge. Of the 47 taxa found, 38 (81%) showed a significant change in expected occurrence in response to at least one of the investigated microclimatic parameters (air and soil temperature, air humidity, light intensity). The results suggest that a substantial number of forest herbaceous species with broad European distributions show particular microclimatic requirements. Furthermore, many species show a different response to combined factors, such as for instance soil temperature with increasing air humidity, which indicates that combinations of microclimatic parameters stronger determine the actual temperature, humidity or light levels at which species are expected to be present or not.     

The effects of temperature and humidity on the nocturnal activity of different shell colour morphs of the land snail Arianta arbustorum

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.     

Humid microclimates within the plumage of mallard ducks (Anas platyrhynchos) can potentially facilitate long distance dispersal of propagules

Birds as carriers of propagules are major agents in the dispersal of plants, animals, fungi and microbes. However, there is a lack of empirical data in relation to bird-mediated, epizoochorous dispersal. The microclimate found within the plumage likely plays a pivotal role in survival during flight conditions. To investigate the potential of epizoochory, we have analysed the microclimatic conditions within the plumage of mallard ducks (Anas platyrhynchos). Under similar ambient conditions of humidity and temperature, a sample of mallards showed a consistent microclimatic regime with variation across the body surface. The highest (mean) temperature and specific humidity occurred between feathers of the postpatagium. The lowest humidity was found between feathers of the centre back and the lowest temperature in the crissum. Observed differences in plumage depth and density, and distance from the skin, are all likely to be determining factors of microclimate condition. Specific humidity found within the plumage was on average 1.8–3.5 times greater than ambient specific humidity. Thus, the plumage can supply a microclimate buffered from that of the exterior environment. Extrapolating survival data for Lemna minor desiccation at various temperature and humidity levels to the measured plumage microclimatic conditions of living birds, survival for up to 6 h can be anticipated, especially in crissum, crural and breast plumage. The results are discussed in the context of potential long distance epizoochorous dispersal by A. platyrhynchos and similar species.     

Environmental conditions and their impact on immunocompetence and pathogen susceptibility of the Caribbean termite Nasutitermes acajutlae

1. Little is known about interactions between environmental conditions surrounding insects and their immune responses. 2. The environment in and around termite colonies, including temperature, relative humidity, soil pH, and light was analysed using principal components analysis (PCA). 3. The relationship between these abiotic parameters and two aspects of termite immunity (phenoloxidase activity and lipid content) was examined in field‐caught workers of Nasutitermes acajutlae Holmgren. Finally, termites from warm/dry and cool/moist habitats were exposed to Metarhizium anisopliae to determine their susceptibility to mycosis. 4. PCA indicated that environmental components external to the nest [ambient temperature, ambient relative humidity (RH), soil temperature and light] comprised the majority (PC1 = 37.5%) of variation. Internal variables (nest temperature and RH) and nest volume accounted for 19.6% (PC2) of the variation with pH comprising 12.9% (PC3). 5. AIC and regression models suggested that ambient temperature was most strongly and positively associated with immune variables and that relative humidity may also play a role. Termites from warm/dry colonies were less susceptible to M. anisopliae than termites from cool/moist colonies. 6. Thus, termites nesting in warmer habitats may exhibit increased immune‐related measures and reduced susceptibility to mycosis compared with termites from cooler habitats.     

淮北平原杨-麦间作系统的小气候效应与土壤水分变化研究

对淮北平原的杨－麦间作系统的小气候效应与土壤水分的研究表明,在冬小麦发育的拔节期和灌浆期,林粮带状间作与对照地相比可以降低农田地面温度1－7℃,提高相对湿度2％－8％,农田日照时数减低量随间作为间距和时间而变化,在范围在4．1％－15．3％之间,农田林网可以提高相对湿度6．4％－11．6％,日照时数减少8．5％－11．75,农林 间作可以提高土壤含水率,幅度随间作密度而定,一般可提高含水率0．67％－3．875,农田林网的土壤含率与林带的方位和离林带的距离有关,在各个方位上均与离林带的距离呈显著负相关。     

玉米大豆对农林复合系统小气候的光合响应

对黄土区核桃(Juglans regia L.)-(玉米+大豆)、李子(Prunus salicina)-(玉米+大豆)农林复合系统小气候效应的研究表明,在玉米和大豆的花期,农林间作系统与对照地相比可以降低农田地面温度1.7-1.9℃,减低风速55%-67%,提高相对湿度6.9%-8.4%,降低光合有效辐射强度13.9%-24.5%和大气CO2浓度5.3-10.9μmol.mol-1。本研究中,单作大豆叶片光合速率午间变化主要受到非气孔的限制作用。逐步回归分析结果表明,光合有效辐射强度和大气CO2浓度是影响林下作物光合速率的主要环境因子。林下小气候可能是作物避免"午休"现象的主要原因。     

不同栽培模式对茶园生态环境及茶叶品质的影响

对陕南茶区的纯茶园、塑料大棚茶园、松茶间作茶园及林篱茶园4种常见栽培模式的茶园生态环境(包括小气候因子、土壤因子)和茶叶中各项生化指标(包括氨基酸、咖啡碱、茶多酚、酚氨比、茶水浸出物)进行了测定.结果表明:不同栽培模式茶园小气候因子有显著差异.相对于纯茶园,塑料大棚茶园、松茶间作茶园和林篱茶园能更有效地改善光照条件、降低环境温度、提高土壤水分和有机质含量、增强空气湿度,提高土壤养分状况.3种复合式茶园茶叶品质也较纯茶园显著提高,氨基酸和茶水浸出物含量显著高于纯茶园茶叶,而茶多酚含量却显著低于纯茶园茶叶.因此,林茶复合栽培模式和大棚模式茶园的生态环境更有利于茶树的生长和茶叶品质的提高.     

Effects of pasture and forest microclimatic conditions on the foraging activity of leaf-cutting ants

The fragmentation and transformation of land cover modify the microclimate of ecosystems. These changes have the potential to modify the foraging activity of animals, but few studies have examined this topic. In this study, we investigated whether and how the foraging activity of the leaf-cutter ant Atta cephalotes is modified by microclimatic variations due to land cover change from forest to pasture. We characterized the microclimate of each habitat and identified alterations in foraging behavior in response to relative humidity (RH), air temperature, and surface temperature along ant foraging trails by synchronously assessing foraging activity (number of ants per 5 min including incoming laden and unladen and outgoing ants) and microclimatic variables (air temperature, RH, and maximum and minimum surface temperature along the foraging trail). There were climatic differences between habitats during the day but not throughout the night, and A. cephalotes was found to have a high tolerance for foraging under severe microclimatic changes. This species can forage at surface temperatures between 17 and 45°C, air temperatures between 20 and 36°C, and an RH between 40% and 100%. We found a positive effect of temperature on the foraging activity of A. cephalotes in the pasture, where the species displayed thermophilic behavior and the ability to forage across a wide range of temperatures and RH. These results provide a mechanism to partially explain why A. cephalotes becomes highly prolific as anthropogenic disturbances increase and why it has turned into a key player of human-modified neotropical landscapes.     

森林与空旷地空气温湿度及土壤温度的长期对比研究

森林对温湿度的影响是其生态功能的基础,为了探讨森林的这种小气候效应,本文采用小气候对比观测的方法,根据2005 -2007年观测资料,对长白山阔叶红松林与附近空旷地温度、湿度等小气候要素进行了差异性研究.结果表明,林内近地表层空气温度白天低于林外空旷地,晚间高于林外空旷地,因而具有较低的日较差.非生长季二者的月平均值差异不显著,但生长季差异明显,月平均气温最高差值出现季节与森林叶面积指数最大值出现时间一致.气温年较差的平均值林内小于空旷地,差值可达6.3℃.年均森林与空旷地土壤温度全年均表现出明显差异,以0℃为界,0℃以上,林内土壤温度低于空旷地,0℃以下高于空旷地,其中2005年1月5 cm深处土壤温度差值达到了5.3℃.空气相对湿度生长季差异较大,其中以7、8月份差异最为明显,2006年7月差值最大,达7.0％.     

Foraging behavior of Melipona rufiventris Lepeletier (Apinae; Meliponini) in Ubatuba, SP, Brazil.

This study describes how the foraging activity of Melipona rufiventris is influenced by the environment and/or by the state of a colony. Two colonies were studied in Ubatuba, SP (44 degrees 48 W and 23 degrees 22 S) from July/2000 to June/2001. These colonies were classified as strong (Colony 1) and intermediate (Colony 2) according to their general conditions: population and brood comb size and number of food pots. The bees were active from dawn to dusk. The number of pollen loads presented a positive correlation with relative humidity (r(s) = 0.401; p <0.01) and was highest between 70 and 90%. However, it was negatively correlated with temperature (r(s) = -0.228; p <0.01) showing a peak between 18 and 23 degrees C. The number of nectar loads presented a positive correlation with temperature (r(s) = 0.244; p <0.01) and light intensity (r(s) = 0.414; p <0.01); it was greater between 50 and 90% of relative humidity and 20 and 30 degrees C of temperature. They collected more nectar than pollen throughout the day, and were more active between 6 and 9 hours. Workers from Colony 1 (strong) collected nectar in greater amounts and earlier than those from Colony 2 (intermediate). The number of pollen, nectar and resin loads varied considerably between the study days. Peaks of pollen collection occurred earlier in months with longer days and in a hotter and more humid climate. The foraging behavior of M. rufiventris is probably affected by the state of the colony and by environmental conditions, notably temperature, relative humidity, light intensity and length of the day.     

Cotton (Gossypium barbadense) production as affected by climatic factors and soil moisture status

This study investigates the statistical relationship between climatic variables and aspects of cotton production (Gossypium barbadense), and the effects of climatic factors prevailing prior to flowering or subsequent to boll setting on flower and boll production and retention in cotton. Also, the study covers the predicted effects of climatic factors during convenient intervals (in days) on cotton flower and boll production compared with daily observations. Further, cotton flower and boll production as affected by climatic factors and soil moisture status has been considered. Evaporation, sunshine duration, relative humidity, surface soil temperature at 1800 h, and maximum air temperature, are the important climatic factors that significantly affect flower and boll production. The least important variables were found to be surface soil temperature at 0600 h and minimum temperature. The 5-day interval was found to be more adequately and sensibly related to yield parameters. Evaporation; minimum humidity and sunshine duration were the most effective climatic factors during preceding and succeeding periods on boll production and retention. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive. The soil moisture status showed low and insignificant correlation with flower and boll production. Higher minimum relative humidity, short period of sunshine duration, and low temperatures enhanced flower and boll formation.     

镇江内江湿地不同演替阶段植物群落小气候日动态

2005年5月,选择镇江内江湿地具有代表性的裸地、虉草群落和芦苇群落,分别代表植被群落的不同演替阶段,测定不同群落、不同层次的光照强度、气温、土温和空气相对湿度,研究其植物群落小气候的日动态.结果表明,随演替由裸地到虉草群落到芦苇群落进行,群落内光照强度、气温和土壤温度均明显降低,日变幅减小.其中,日均光照强度由1 204.7 μmol·m^-2·s^-1降至141.28 μmol·m^-2·s^-1,日均变幅由1 126μmol·m^-2·s^-1降至265 μmol·m^-2·s^-1;日均气温由32.2 ℃降至24.9 ℃,日均变幅由12.75 ℃降至4.8 ℃;日均土温由21.83 ℃降至19.47 ℃,日均变幅由4.5 ℃降至2.1 ℃.群落内空气相对湿度明显升高(由58.95%增至87.3%）,变幅减小(由29.75%降至5.15%）.生境具有早期的开放性和后期的封闭性,小气候环境朝着更为阴、凉、湿的环境变化,且波动性减弱,稳定性增强.各群落内的光强、气温、湿度及土温之间均存在一定相关,但不同演替阶段各因子间相关程度各异.     

Microclimatic adaptation and differences in food consumption and assimilation efficiency of different shell colour morphs of the land snail Arianta arbustorum

Food consumption and assimilation efficiency of different shell colour morphs adapted to various microclimatic conditions were determined. Five-factor analysis of variance (adaptation temperature, relative humidity, phenotypic shell colour, age class and time of acclimatization) was used. There are differences between different levels of adaptation temperature and relative humidity in the effect on food consumption in the two morphs. The interaction of these two factors is also significant. There is no effect of the phenotypic shell colour on the food consumption, but there is a relation between shell colour and adaptation temperature. Food consumption is greater in the juveniles. The interactions between age class and adaptation temperature or relative humidity are relevant. Acclimatization to these conditions shows a highly significant effect on the food consumption. The brown and yellow morphs of Arianta arbustorum consumed different amounts of food in relation to the adaptation temperature.
Assimilation efficiency is independent of temperature but declines at high relative humidity. There is a relation between adaptation temperature and relative humidity, but not between the phenotypic shell colour and age class factors. The yellow morphs show higher assimilation efficiencies than the brown morphs during cold adaptation to 5 °C and at the highest level of relative humidity (98%).     

土壤水分状况及环境条件对水稻蒸腾的影响

在南方红壤区用田间测坑试验,研究了高、中、低3种土壤水分条件下的早、晚稻蒸腾速率和水分利用效率的变化,蒸腾日变化结果表明,蒸腾速率受许多田间小气候因子的影响,相关分析及多元逐步回归分析表明,叶片与空气相对湿度差和叶面温度对水稻叶片蒸腾影响最大,处理B（中等土壤水分条件）可以明显提高叶片水利用率和产是,处理C提高了叶片水分利用效率,却导致晚稻减产,早稻中、低土壤水分条件可以减小叶片蒸腾速率,而晚稻上并不能明显减少叶片蒸腾。     

冬小麦田秸秆覆盖的小气候效应

近年来,国内外对秸秆覆盖的整体功能和节水效应[1～4]已有较多研究,但对秸秆覆盖地的小气候效应研究较少。小气候效应能够反映秸秆覆盖的机理和功效,为秸秆覆盖的进一步研究提供科学依据。本文对不同水分条件下的秸秆覆盖处理进行了研究,目的是了解秸秆覆盖冬小麦田的小气候效应。1　设计与方法1.1　试验地点试验于1996～1997年在郑州市南郊河南省气象局科学研究所试验基地进行。试验地土壤为砂壤土,肥力中等。小麦供试品种为温麦4号。1.2　试验设计试验设置了麦秸覆盖、玉米秆覆盖、裸地(对照)三种形式,以及土壤含水量占田间持水量的40%～5…     

Effect of nest-site microclimatic conditions on nesting success in the Lesser Kestrel Falco naumanni

Capsule: Microclimatic conditions in the nests of the Lesser Kestrel Falco naumanni, particularly the percentage of time of extremely low humidity, affect breeding success.

Aim: To study the effect of within-nest temperature and humidity on nest productivity, and the correlation between nest productivity and the order of dates on which nests were occupied by the parents. To compare microclimatic conditions in the nest, breeding success and order of occupation between nests under tile roofs and in artificial nest boxes.

Methods: Three different Lesser Kestrel colonies were monitored in Israel – one rural, one urban and one in an open country habitat. Data loggers were placed in 39 nests for the entire breeding period to measure temperature and humidity. The number of fledglings was recorded for each nest, as well as the date of occupation.

Results: Full microclimatic data from 35 nests suggest that percentage of time of extremely low humidity is the major predictor of nest productivity – low humidity is negatively correlated with nest productivity. Sites of more successful nests were occupied earlier. Considering only successful nests, the urban colony had the lowest breeding success of the three colonies. There was no significant difference in mean productivity between nests in roofs and nest boxes, but nests in roofs were occupied earlier.

Conclusion: Nest microclimate, particularly low humidity, affects nesting success in addition to colony location.     

羊草草原枯枝落叶分解的研究——枯枝落叶分解与生态环境的关系

枯枝落叶的分解受生态环境的影响,枯枝落叶置于不同的生态环境下,其分解速率不同。例如,羊草(Leymus chinensis)在6种不同生境中的分解存在着明显差异。枯枝落叶位于地表和地下,其分解速率则不同,埋入地下的分解比位于地表的迅速。分解速率与土壤水分、地表温度和土壤pH呈指数正相关,与相对湿度呈线性正相关,它们对分解有积极的促进作用。通过生态因子对分解影响的综合分析表明,在羊草草原上,诸生态因子对枯枝落叶分解的重要性依次为:土壤水分、土壤pH、地表温度、相对湿度。     

西双版纳望天树林林窗小气候特征研究

 对西双版纳望天树林林窗小气候要素的季节变化、水平差异进行了观测研究,并对比分析了两个大小不同林窗内温度垂直分布状况、相对湿度差别。结果表明：大林窗内温度、湿度、光照的日变化均比林内大;大林窗中央光照强度为林内的10倍以上,太阳总辐射量、净辐射量为林内的5倍以上,大林窗中央的蒸发耗热量大于林内,且均占各自净辐射的较大比例(70％～80％),干季大林窗内温度、湿度日变化比雨季剧烈,大林窗内具有两个加热层(幼苗冠层、地表),小林窗仅有一个加热层(幼树冠层),且前者的加热强度大于后者,相对湿度日变化则是大林窗内较剧烈。     

Choice of nest site protects army ant colonies from environmental extremes in tropical montane forest

Unlike most social insects, Eciton burchellii army ants cannot thermoregulate through nest construction. Instead, army ants thermoregulate behaviorally by creating a living nest (bivouac), shifting its position and structure, and potentially through nest site selection. We hypothesized that bivouac site selection is critical to E. burchellii colony survival. We predicted elevation above sea level, with associated variation in local abiotic environments, would affect bivouac site selection by E. burchellii colonies. We also expected nest sites to buffer against ambient variation in abiotic conditions. We recorded bivouac site choice by E. burchellii colonies at sites ranging from lowland wet forests to montane forests and reviewed previously published data. We measured microclimatic variables associated with nest sites in high-elevation montane forests: temperature, relative humidity, and light levels. Bivouac site selection varied with elevation: as elevation increased, fewer bivouac sites were exposed, more were underground, and fewer were elevated (in trees). High-elevation bivouac sites moderated diurnal temperature variation and had higher relative humidity levels and lower light levels than ambient conditions. The buffering of ambient temperature and humidity decreased with elevation in montane forests, suggesting that abiotic extremes in bivouac sites at the highest elevations may contribute to the upper elevational range limits of E. burchellii.