四川省雅安地区蚊类越冬情况的调查

1955年至1984年对四川雅安地区25种蚊类越冬情况作了初步调查,结果发现以成蚊越冬者6种;以成、幼虫越冬者1种;以成虫及卵越冬者2种,以幼虫越冬者4种,以幼虫及卵越冬者1种;以卵越冬者2种;无明显越冬期,冬季仍能繁殖发育者9种,各蚊种的越冬情况记述如下。     

东北稻区二化螟越冬幼虫的生物学研究

二化螟Chilosuppressalis是我国东北地区最重要的水稻害虫。连续 3年在东北稻区的二化螟越冬幼虫调查表明 ,在通河和方正两地 (北纬 46°附近 )出现不完全第 2代 ;在东北稻区 ,二化螟幼虫多以高龄幼虫在稻茎内越冬 ( 1 999～ 2 0 0 1年分别占总数的 44 47% ,5 3 47%和 63 48% )。在盘锦、五常、吉林和龙井 4地区的平均高度分别为 8 0 2 ,1 6 2 5 ,1 8 2 9和 2 0 3 4cm。同时 ,在东北稻区的越冬幼虫的头向多朝上 ( 65 74%～ 76 77% )。     

宜宾地区库蚊越冬情况观察

1985—1988年对宜宾地区的库蚊Culex Linnaeus,1758越冬情况作了观察,现将结果报告于后。方法每次于11月至翌年3月,各月捕捉40至60处次越冬场所的成蚊分类计数,并根据B.H.BeKпeMишeBa,1949的方法对脂肪体分级。同时对各型积水进行调查,将所获幼虫(蛹)置室内隔离饲养。以各虫期综合分类鉴定。结果捕获9种库蚊成虫276只,幼虫(蛹)2987只(见表)。表1985—1988年越冬库蚊观察蚊虫种类虫态各月捕获数(只)越冬场报1112123小计致倦库蚊成虫*172842189114室内、山洞Culex quinquefasciatus幼虫464298285△207△4811735废粪坑、污水坑小斑翅库…     

棉铃虫老熟幼虫有效越冬虫量的分析

通过从棉田和玉米田采回的第 4代老熟幼虫的化蛹率和羽化率观察 ,发现棉田和玉米田的老熟幼虫化蛹率分别为 65%～ 83 0 5%和 55%～ 80 % ,其化蛹后的羽化率分别为 1 0 %～ 87%和 1 3 %～77% ,而且 2种寄主作物间无显著差异。由此进一步分析了棉田和玉米田老熟幼虫的有效越冬虫率和有效越冬虫量 ,作者认为 8月 3 1日至 9月 1 0日是棉铃虫老熟幼虫有效越冬虫量的主要来源期 ,且棉田显著高于玉米田 ,构成了第 2年棉铃虫种群发生基础。     

湖南江口苍鹭越冬生态观察

1992－1997年对湖南鸟洲自然保护区苍鹭越冬种群进行了观察。苍鹭每年11月上旬迁来鸟洲,次年4月中旬迁离,鸟洲保护区及其附近的芦苇沼泽地苍鹭越冬种群数量相对较多。     

山东省亚洲玉米螟越冬特性及越冬代成虫发生期预测

【目的】亚洲玉米螟Ostrinia furnacalis(Guenée)是我国玉米生产上的重要害虫。亚洲玉米螟越冬特性及预测预报的研究,对于提高防治效果具有重要意义。【方法】本文通过对山东省东昌府、曲阜、商河、滨城区、即墨和栖霞地区玉米秸秆和穗轴进行剖查,统计越冬幼虫虫量和位置分布。并将幼虫带回济南放于室外待其化蛹,统计化蛹时间及存活率。【结果】山东省6个地区2007年春季玉米秸秆和穗轴中亚洲玉米螟平均越冬虫量分别为41.80头/百秆和19.91头/百穗,其中在玉米秸秆中越冬虫量占总量的67.30%。越冬幼虫在玉米秸秆上、中和下部比例分别为21.18%、38.80%和40.02%。越冬代亚洲玉米螟化蛹始盛期、高峰期、盛末期分别为5月27日、6月5日和6月21日,预测越冬代羽化始盛期、高峰期和盛末期分别为6月8日、6月17日和7月1日。【结论】应重视对亚洲玉米螟越冬虫源的控制,及时处理玉米秸秆和穗轴,第一代幼虫应该在6月中下旬防治,第二代应该在7月中旬防治。     

侧柏毒蛾越冬虫态探讨

记述了侧柏毒蛾在湖南省衡阳地区的越冬虫态 ,并对该虫在我国其他地区的越冬虫态进行了探讨。通过对有关资料的分析 ,认为侧柏毒蛾在我国南北均以胚胎发育完全的幼虫在卵壳内越冬     

果园梨小食心虫越冬幼虫与成虫发生的关系

【目的】探明梨小食心虫Grapholita molesta (Busck)在果园中的越冬场所及越冬幼虫与越冬代成虫发生的关系, 为更好地防治梨小食心虫提供科学依据。【方法】选取山东省不同地区（济南、泰安、肥城、广饶、莱芜）6个代表性的果园进行系统调查, 刮树皮调查记录梨小食心虫越冬幼虫在树体上的分布和存活情况, 利用封闭纱网调查土壤中梨小食心虫越冬幼虫数量, 同时利用性诱集和糖醋液对越冬代成虫发生量进行监测, 分析同园越冬幼虫与成虫发生的关系。【结果】梨小食心虫幼虫平均越冬成活率高达62.99%; 不同果园间梨小食心虫的越冬幼虫数量差异显著（P<0.001）。 越冬场所选择更倾向于树体下部（45.10%）和中部（46.28%）以及相应的主干（28.48%）和主枝（44.24%）, 而位于树体上部(8.62%)及相应的侧枝(27.28%)的相对较少; 对树枝方位的选择没有显著差异（P>0.05）（东27.57%, 西26.13%, 南23.76%, 北22.54%）。同园越冬幼虫数量与越冬代成虫诱集数量无显著相关性。【结论】梨小食心虫以老熟幼虫在果树中、下部主干和主枝及树干周围的土壤中越冬。梨小食心虫在果园调查获得的越冬幼虫数量不能作为该果园翌年越冬代成虫发生和防治的依据, 发生危害情况还需根据周围环境情况做综合考虑。     

泰安地区松阿扁叶蜂越冬幼虫抗寒性

松阿扁叶蜂越是松树的重要食叶害虫之一。其幼虫在松林土壤中越冬,越冬幼虫的抗寒能力影响翌年的种群密度和危害程度。用NTC-TD热敏电阻 数字电表法研究了越冬幼虫的过冷却能力并调查了越冬场所、龄期、死亡率等。结果表明:越冬幼虫的过冷却点随外界温度的高低而变化。4、5、6龄越冬幼虫平均过冷却点依次由越冬初期的-19.3℃-、20.3℃-、21.6℃降至越冬期的-22.5℃-、24.8℃-、23.1℃,冰点依次由越冬初期的-12.8℃-、12.9℃-、12.1℃降至越冬期的-14.1℃、-16.8℃-、15.3℃。从越冬期进入早春出蛰期后,随着温度的回升,过冷却点也随之升高。调查林间越冬幼虫龄期表明,4龄、5龄、6龄皆有,以5龄为最多,占53%;越冬幼虫以山坡中部和顶部土壤瘠薄处虫口密度较小,分别占28.6%和29.3%,山坡基部土层较厚处密度较大,占42.1%;越冬幼虫在树冠内的分布,以南部方位最多(27.0%),东部方位(26.3%)和西部方位(25.6%)略少,北部方位最少(21.1%);调查幼虫死亡因子,以真菌感染致死最多,占总死亡数的42.4%,细菌和其它因子分别为28%和29.7%。     

盐城滩涂丹顶鹤越冬数量分布与生态研究

江苏省沿海滩涂为丹顶鹤在我国的主要越冬地。1982年—1987年我们对沿海的响水、滨海、射阳、大丰和东台五县滩涂进行了调查,该地区海岸线长406公里,面积约400余万亩。滩涂上以软体动物最为丰茂,并生长有大量芦苇,提供了良好的栖息环境。四年来的调查获知:响水、滨海两县丹顶鹤的数量逐年减少,而射阳、大丰和东台三县数量逐年增长,以射阳和大丰最为集中,每年可达200只以上。     

Water levels andPhragmites: Decline from lack of regeneration or dieback from shoot death

This contribution combines field observation with the literature to argue that stabilised water levels are contributing to reed decline through a lack of vegetative and generative reproduction, and that eutrophic conditions exacerbate this situation. The focus on what causes reed shoots to die has increased our knowledge of what limits the distribution of reed without necessarily increasing our understanding of reed decline. This raises the question as to whether reed beds are in fact dying, or whether reed decline is observable only in the absence of regeneration. The distribution pattern and life-history of reed suggests that generative reproduction is lacking. It is proposed that the temporal at which seedling establishment takes place is similar to the time-frame of observed reed decline (10–50 years). As an “encompassing” factor, water regime influences many of the specific factors under investigation. Its role is therefore consistent with agreement in the literature that reed decline is caused by combinations of factors.     

Management of reedbeds: mosaic reed cutting does not affect prey abundance and nest predation rate of reed passerine birds

Reed passerine birds are strict habitat specialists inhabiting reedbed habitats. In Europe, many of these species are threatened due to loss and degradation of natural reedbeds. Another important factor that can negatively affect the abundance of reed passerines is commercial reed harvesting. Previous studies have shown negative impacts of large-scale winter reed cutting on passerine breeding assemblages and arthropod communities. The effect of reed cutting on a small scale, however, has not been studied experimentally to date. The aim of this study was to investigate whether and how small-scale, mosaic reed cutting influences prey abundance and nest predation rate of reed passerines. In June, after the reed had reached maturity, we conducted nest predation experiments with artificial nests and arthropod sampling using pan traps in cut reed patches, adjacent uncut reed patches and unmanaged reedbed. We found no differences in the risk of egg predation between three types of reedbeds. In contrast, the abundance of arthropods in cut and adjacent uncut reed patches was significantly higher than that in unmanaged reedbed. We assume this was caused by habitat heterogeneity, small size of cut patches and their rapid recolonization by arthropods from adjacent uncut patches. Our results suggest that in contrast to large-scale reed cutting, small-scale, mosaic reed cutting has no negative effect on nest survival and food abundance of reed passerine birds. However, given that we performed all experiments in June, i.e., when the reed was mature, our findings cannot be generalized to whole breeding period of all reed passerine birds. Therefore, temporal variation in nest predation rate and arthropod abundance in managed and unmanaged reedbeds during the entire breeding season should be examined in future studies.     

Changes of element ratios of cultured cells from dune reed under adverse environmental conditions

Dune reed, as an ecotype of reed plant (Phragmites communis Trin.), is an ideal material for studies on the adaptations of plant to environmental conditions. Scanning electron microscope, energy-dispersive X-ray analysis, and plant tissue culture techniques were used to investigate the effect of extreme temperature, salt, and polyethylene glycol-induced osmotic stress on the intracellular elements K, Na, Ca, and Cl in cultured cells from dune reed and swamp reed (as control). The results indicated that the percentages of the studied elements in dune reed cells exposed to various stresses increased or decreased obviously compared to the swamp reed cells. It has been found that a pattern of absorbing K and discharging Na exists in dune reed cells, which did not exist in swamp reed cells. The pattern is thought to be a significant physiological mechanism of the dune reed response to adverse environmental factors. In addition, the percentages of Ca and Cl in dune reed cells were also shown to increase at high temperature. The growth of cells along with their surface features under different stress conditions were observed and the results are discussed.     

Chronological relationship between eutrophication and reed decline in three lakes of southern Germany

Eutrophication is often considered to play an important role in reed decline. We decided to use a chronological comparison of the two phenomena as a useful aid in the search for a possible causal relationship between them. Eutrophication is usually documented by changes in phosphorus and nitrogen content in water but there are no such data older than 10 years available for most of the lakes in which reed decline has been observed. The entire historical record of eutrophication has been recently reconstructed from micropaleontological analysis of indicatory diatom frustules, deposited in sediments in three lakes in south Germany. In these lakes, reed decline was well documented by archival aerial photographs. The comparison of reed decline history with the reconstructed changes in water quality confirmed the coincidence of reed decline and eutrophication. Consequently, eutrophication cannot be excluded as a potential cause of reed decline in any lake in this study.     

芦苇生态型研究进展

芦苇生态幅极广,适生于多种生境类型。不同的环境选择压力如水深、盐度、养分、气候等交互影响致使芦苇个体及种群间发生不同程度的分化和变异,形成了形态、生理或遗传上互有差异、异地性的不同生态型。尽管基于芦苇表型变异以及遗传变异进行生态型划分的研究已开展很多,但针对芦苇生态型变异规律及其可能的形成机制的认知仍存在较多分歧。在总结近年来有关芦苇生态型研究文献的基础上,通过对影响芦苇生态型变异的主要因素——环境因素和遗传因素的分析,以期为芦苇生态型的划分及其可能的形成机制提供新的研究思路。(1)空间尺度的选择应成为研究者分析、划分芦苇生态型的首要定位。在较大的地理空间尺度上,高度异质性的生境导致某些性状的变异式样具有相对的不连续性,可作为不同芦苇生态型鉴别与描述的主要依据;(2)在合理的尺度定位、取样设计和统计分析的基础上开展的表型变异研究,及进一步基于种群水平的分子标记研究(分子指纹特征或特有等位基因),可为芦苇生态型的鉴定、划分提供更为可靠的参考数据,并且可以甄别生境差异(环境响应)和遗传变异对芦苇不同生态型分化的贡献;(3)应同时进行不同生态型的特定性状与功能(株高、茎粗、生物量、生理抗逆性、水体污染物净化能力等)的定位,推动优良基因型的选育与扩繁。     

Limited overlap of the community of bees and wasps (Hymenoptera: Aculeata) nesting in reed galls with those nesting in other cavities

Hymenopterans occurring in wetlands represent specific community with bioindicative characters but poorly understood nesting biology. We have studied the nesting preferences of these insects in ten reed beds—five represented by natural wetlands, and the other five localized to anthropogenic sites. We reared the hymenopterans from trap-nests consisting of reed stalks and goldenrod stems, which were installed at the localities through the nesting season, and compared them with quantitative data of hymenopterans reared from reed galls collected at the same localities. Most of the species that nested in reed galls accepted the reed stalk traps but not vice versa. Some of the species that accepted both these nesting resources strongly differed in their frequency of use of these two nesting resources. Moreover, the species composition differed substantially between goldenrod stems and either reed stalks or reed galls. The digger wasp Pemphredon fabricii was eudominant in reed galls with higher abundance at anthropogenic sites, while it was also observed in reed stalks but in much lower numbers. Hylaeus pectoralis was frequent in reed galls at both habitat types and only one individual was reared from reed stalks. Trypoxylon deceptorium was quite numerous in reed galls but much more frequent in reed stalks. Species unknown from reed galls (Psenulus pallipes, Hylaeus confusus, Gymnomerus laevipes) were numerous in reed stalks. We experimentally confirmed that P. fabricii and H. pectoralis show high preference of reed galls and are dependent on these nesting resources. The available evidence suggests that the management of both natural and anthropogenic sites needs to implement tools preserving reed beds, especially the terrestrial ones with reed galls.     

四种生态型芦苇叶片结构的研究

采用光学显微镜和电子显微镜对４种生态型芦苇（ＰｈｒａｇｍｉｔｅｓｃｏｍｍｕｎｉｓＴｒｉｎ．）叶解剖结构及叶脉维管束鞘细胞超微结构进行了观察研究。结果表明,沼泽芦苇维管束鞘细胞内含物较少,维管束鞘细胞叶绿体呈近圆形,超微结构与典型Ｃ３植物小麦鞘细胞的相似,基粒发育退化,不含淀粉粒;沙丘芦苇鞘细胞内含物较多,鞘细胞叶绿体呈近椭圆形,超微结构与典型Ｃ４植物玉米的相似,具有不发达的基粒;重度盐化草甸芦苇鞘细胞内含物则较沼泽芦苇多,而较沙丘芦苇少,鞘细胞叶绿体形态、超微结构与沙丘芦苇相似;轻度盐化草甸芦苇鞘细胞内含物与沙丘芦苇相似,但是,其鞘细胞含有与沼泽芦苇鞘细胞内叶绿体形态相似的近圆形以及与沙丘芦苇和重度盐化草甸芦苇鞘细胞内形态相似的近椭圆形两种形态的叶绿体。表明生长在同一地区不同环境中的４种生态型芦苇的光合结构发生了深刻的变异,表现出从Ｃ３向Ｃ４进化的明显趋势。     

四种生态型芦苇叶片结构的研究

The leaf anatomy and uhrastructure of the vascular bundle sheath cells of four ecotypes of reed (Phragmites communis Trin. ) were observed with light and electron microscope. The four ecotypes were the swamp reed, dune reed, heavy salt meadow reed and the light salt meadow reed. It was shown that the intracellular content of the vascular bundle sheath cells of the swamp reed was lower than that of the dune reed; that of the heavy salt meadow reed was between that of the former two reeds and that of the light salt meadow reed and that of the light salt meadow reed was similar to the dune reed. The chloroplasts in the swamp reed were round-shaped with poorly developed grana. Starch grains were not visualized. The uhrastructure of their chloroplasts were similar to those in the typical C3 plants as wheat. By contrast, the chloroplasts in the vascular bundle cells of the dune reed were elliptical with their structure similar to that of the typical C4 plants as maize. These chloroplasts contained some poorly developed grana thykloid. The chloroplasts of the vascular bundle sheath cells in the heavy salt meadow reed were similar to those seen in the dune reed, however, those in the light salt meadow reed appeared to be beth round .and elliptical in shape. The above results suggested a great habitat variation did occur among the four ecotypes of reed in which these exists an obvious evolutional trend from C3 to C4 plants.     

Effects of winter harvest on water and sediment chemistry in a stand of reed (Phragmites australis)

An investigation of the effects of repeated winter harvest and removal of dry reed culms on water and sediment chemistry was made in a shallow lake dominated by closed, monospecific reed stands. The oxygen concentration and redox potential in the water, as well as temperature, showed regular diurnal fluctuations inside the reed stands. Ammonium and nitrate + nitrite did not exhibit diurnal fluctuations and differences between a harvested and an unharvested reed area were small. Molybdate reactive phosphorus (MRP) concentration was higher in the unharvested area.Because the winter harvest caused an almost doubling of shoot production compared to the unharvested area, net addition of reed litter (leaves, stubble and culms) to the sediment of the harvested area was similar to that of the unharvested area. It is concluded that removal of reed culms in winter has the largest effect on microclimate in spring, and that the rate of mineralization and reducing intensity in the substrate are not immediately affected. Significantly higher summer standing crop of reed after harvest may have caused lower phosphate concentration in the water column and sediment interstitial water.     

Territorial spacing and interspecific competition in three species of reed warblers

Summary Ecological and temporal aspects of the occurrence and dispersion patterns in three reed warbler species were examined. This provided insight into their intra-and interspecific territoriality. Seasonal changes in the occurrence of territorial males in a reed bed along a gradient from the shore landward were studied. The results demonstrate that intra- and interspecific spacing depends on interspecific dominance and/or ecological constraints. In this case it was shown that there is competition for common habitats between reed warblers and great reed warblers, whereas the moustached warbler is ecologically segregated. The reasons for these dispersal patterns are discussed. They do not appear to enhance the availability of food resources. It seems more likely that territorial spacing might function to reduce nest predation.