疣鼻天鹅的分布、迁徙及其保护——以达赉湖自然保护区为例

2006年8月至2007年8月,对内蒙古达赉湖国家级自然保护区疣鼻天鹅的分布现状和迁徙动态进行了研究.结果显示:疣鼻天鹅主要分布于乌兰诺尔核心区,通常4月初开始迁来,迁徙高峰期为5月下旬至6月初,数量最多时达68只,少数迁徙个体停留到7月10日.繁殖个体通常10月下旬迁离,秋季未见其他迁徙个体路过保护区.柄息地的缩减和退化以及旅游、捕捞、拣鸟蛋、狩猎等为疣鼻天鹅的主要受胁因素,保护区应采取相应的管理对策.     

苹果蠹蛾羽化产卵及卵孵化的昼夜节律

在光周期L∥D = 16 h∥8 h、温度(25±1)℃条件下对苹果蠹蛾 [Cydia pomonella (L.)］成虫的羽化、产卵及卵的孵化节律进行了观察,结果表明：①苹果蠹蛾主要在白天羽化,羽化高峰主要集中在08:00-13:00,此时段羽化数占总数的50.18%。②雌虫羽化当天不产卵,羽化后第2天开始产卵,可持续到羽化后的第9天;产卵主要集中在羽化后的2~5 d,其产卵量占总卵量的91.9%。③雌虫日产卵时间主要集中在18:00-22:00,日产卵高峰期为19:00-21:00,高峰期产卵量占总卵量的70%。④卵在白天孵化,孵化时间集中在05:00-18:00,其孵化数占92.8%,08:00-09:00达到卵的日孵化高峰。     

云南省玉溪市草地贪夜蛾发生动态及特点

云南省玉溪市是我国草地贪夜蛾周年繁殖区。在2019—2021年,利用田间调查、性诱、高空灯诱等手段,对玉溪市草地贪夜蛾发生动态进行了调查。结果表明,草地贪夜蛾主要为害玉米,零星为害甘蔗、小麦、皇竹草;草地贪夜蛾在玉溪市可周年发生,在夏、秋季出现成虫诱捕高峰,2020、2021年发生程度轻于2019年;草地贪夜蛾成虫以夜间活动为主,18:00至翌日4:00成虫诱集量占24h总诱集量的82.55%,在19:00—20:00和23:00至翌日2:00各具1个诱集量高峰。     

大猿叶虫卵孵化的时辰节律研究

在20℃,22℃,25℃,28℃和30℃,LD14:10下观察卵孵化的时辰节律。结果表明,在这五种温度下,卵孵化呈现两个孵化高峰:第一个高峰出现在6:00-6:59,也就是黎明这段时间;第二个高峰出现在19:00-19:59,也就是黄昏这段时间,但此时的孵化率明显低于前者。     

柑橘大实蝇自然行为学研究

2013年~2016年在自然条件下连续3年观察,清江河谷地带柑橘大实蝇羽化出土时间在5月5日至5月15日;成虫入园时间在5月25日至6月5日,交配产卵高峰期在6月15日至6月30日,园内终见时间在7月下旬;成虫在园内活动高峰时段为15:00~17:00;老熟幼虫9月下旬开始入土化蛹,虫果脱落高峰期在10月中下旬。抓住大实蝇自然行为关键时期进行防治才能提高防治效果。     

茶尺蠖生物学习性研究

本试验对茶尺蠖的生活习性作了进一步的研究。结果表明,茶尺蠖成虫羽化后,大多于次日晚20:00～凌晨01:00交尾,交尾高峰集中在22:00～23:00,翌日黄昏开始产卵,20:00～00:00产卵最多。不同叶位饲养幼虫对其生长发育影响很大。咀食嫩叶的幼虫生长最快,化蛹率较高;食成老叶的生长较快,化蛹率最高;而食芽头的生长最慢,化蛹率最低。     

塔里木沙漠公路防护林乔木状沙拐枣耗水特性

利用植物茎流计,测定了塔里木沙漠公路塔中段乔木状沙拐枣茎干液流变化及耗水特性.结果表明3株乔木状沙拐枣在一个生长季内的日平均耗水量为4 183.4 g;在现行的灌溉管理条件下,4～10月3株基径为3.6,3.1,1.9 cm的乔木状沙拐枣日平均耗水量分别为6 203.5,4 829.1,1 517.5 g;7月份是耗水量最大的季节.乔木状沙拐枣液流日变化呈单峰曲线型,并随环境因子的变化有所波动;液流高峰值出现在12:00～15:00,最小值出现在0:00～3:00,夜间仍保持较高的液流速率.乔木状沙拐枣液流速率与基径呈正相关关系,在6月底,3株基径为3.6,3.1,2.1 cm的乔木状沙拐枣日耗水量分别为9 521.2,5 803.1 g/d和1 818.8 g/d.不同天气条件下沙拐枣日平均率日耗水量的排列顺序为:小雨＜阴天＜浮尘＜沙尘暴＜多云＜晴天.干旱的环境条件和较为充足的水分供应是耗水量大的一个重要原因.     

赤眼蜂Trichogramma sp.nr.mwanzai成蜂羽化数量和时间的观察

据作者在肯尼亚国际昆虫生理生态中心观察,寄生于玉米禾螟(Chilo partellus)卵的赤眼蜂T.sp.nr.mwanzai,每日羽化时间在6:00～13:00之间,羽化高峰在8:00～10:00之间。在这段时间内羽化蜂的数量占当日羽化蜂总数的70％以上。雄蜂与雌蜂均遵循这一节律,出蜂的性比基本一致。上午7:00、8:00、9:00、10:00和11:00时,羽化雌蜂所占百分比分别为85％、84.7％、87.8％、71.4％和80.9％。     

莫索湾1961-2010年大风特征分析

对1961-2010年莫索湾大风观测资料进行统计分析,结果表明:近50年来,莫索湾大风发生频数总体呈下降趋势,下降次数为0.0187次/年。4-7月是莫索湾大风频发期,11月到次年3月没有出现过大风。莫索湾大风的日变化特点是:大风多出现在13:00以后,至19:00左右减弱,16:00-18:00是大风出现次数最多的时段,并且风向以西北风居多。莫索湾大风的天气特征主要有三种:冷锋过境型大风、动量下传型大风和热力对流型大风,其中以冷锋过境型大风出现次数居多,约占大风总次数的83%。最后提到大风预报的着眼点和防御大风的对策措施。     

沙冬青等3种沙生植物气体交换特征

在乌兰布和沙漠使用LI-6400植物光合测定系统和压力室同步测定了白刺、沙冬青和油蒿气体交换和水势等的日变化和月变化。白刺、沙冬青和油蒿气体交换日进程变化呈单峰、双峰和多峰。白刺的水势、光合速率、蒸腾速率的日变化曲线多呈单峰型,一般在11:00达到高峰。油蒿水势和光合速率的日变化多呈单峰型,其峰值分别出现在13:00和17:00,蒸腾速率多呈双峰型,峰值分别出现在11:00和15:00。沙冬青的水势、光合速率、蒸腾速率均呈双峰型。白刺光合速率和蒸腾速率都大于沙冬青和油蒿,研究表明沙冬青和油蒿对于环境变化具有较强的敏感性,而白刺对于环境变化具有较强的忍耐性。被试3种植物水分利用效率相对都较低,其排序为:油蒿(2.83μmol CO2·mmol-1H2O)沙冬青(2.59μmol CO2·mmol-1H2O)白刺(1.96μmol CO2·mmol-1H2O)。研究进一步说明较低的水分利用效率是沙生植物长期适应干旱高温气候环境的结果。     

Mute swan grazing on winter crops: Evaluation of three grazing deterrents on oilseed rape

The population of mute swans Cygnus olor (Gmelin) in the UK has increased since 1986 to >25 000 birds, leading to increased complaints of damage to winter crops, and the need for cost-effective management measures. Using a randomized block design in a split-field experiment, the effectiveness of three licensed grazing deterrents was evaluated for mute swans feeding on oil-seed rape: (1) a ziram-based chemical repellent (AAprotect TM at 10 kg ha -1 ), (2) white flags (25 flags ha -1 ), and (3) hazard warning tape (1000 m ha -1 ) with twine (400 m ha -1 ). Deterrents and control (no treatment) were assigned to one of four plots (approximately 1 ha) in each of four fields. From 4 December 1998 to 26 March 1999, grazing intensity was estimated by counting mute swan droppings on plots at approximately 2-week intervals. Over the entire study (10 - 15 weeks depending on field), total numbers of droppings did not differ significantly between treatments. Over the initial 8 weeks, however, droppings were significantly lower on tape/twine. Tape/twine may therefore potentially be cost-effective in reducing mute swan grazing, and further work is recommended to refine the technique.     

陕西延川枣镰翅小卷蛾发生规律

为有效监测和防治枣镰翅小卷蛾,采用性诱剂诱捕的方法,观察了枣镰翅小卷蛾成虫的发生消长动态。结果表明,枣镰翅小卷蛾在陕西延川1年发生3~4代,其中以1年发生3代为主,个别的发生4代;越冬代成虫在3月中下旬开始羽化;有世代重叠现象;在枣树高度1.0~2.0m范围内,诱集到的成虫数量有一定差异,2.0m处分布最多,在运用性诱剂诱杀枣镰翅小卷蛾成虫时,应尽量将诱集器在枣树高度近2.0m处,以达到更好的诱捕效果;成虫活动时间主要在20:00-24:00及4:00-6:00时间段,其中在20:00-22:00及4:00-6:00时段活动更频繁、更活跃。     

Use of a selective medium to study the dispersal of ascospores ofSclerotinia sclerotiorum

A selective medium (potato dextrose agar with pentachloronitrobenzene and streptomycin) was used to assess dispersal of ascospores ofSclerotinia sclerotiorum in the field. This medium inhibited development ofMucor spp. andRhizopus spp. without affecting the germinability ofS. sclerotiorum ascospores or the production of sclerotia. The number of viable ascospores started increasing in December, was maximal from January to February, and decreased sharply in March. Deposition of ascospores on plates was maximal (57%) between 10:00 and 13:00 hours. Seventy-seven to 90% of the ascospores were deposited within the first 100 m from the source of inoculum and the rest were transported farther.     

2000-2009年新疆雷电灾情分析

对2000-2009年气象部门收集的雷灾资料进行统计分析,研究新疆雷电灾情的时空分布特征、受损财物与受伤害人员情况等。资料包括97次雷灾事件,其中30次雷灾造成了31人死亡,15人受伤。新疆雷灾发生在3~9月,夏季占78%以上,6月最高。造成人员伤亡和财产损失的雷灾主要发生在11:00~24:00时,17:00~18:00时为峰值。雷灾致人员伤亡的雷击地点,发生在户外的最多。     

斜纹夜蛾雌雄配对后成虫活动行为节律及时间分配

为了解斜纹夜蛾Spodoptera litura(Fabricius)配对后雌、雄成虫日活动行为节律,在室内人工气候室中配对饲养斜纹夜蛾,连续6 d观察成虫移动、静息、补充营养、产卵和交配5个行为类型。结果表明,在配对后6 d内,斜纹夜蛾的交配、产卵、移动、补充营养和停息行为所占比例均有明显变化,交配行为主要发生在配对后的前2 d,在配对后第6天成虫除偶尔补充营养外基本处于停息状态;交配行为有2个明显高峰期,即00∶00~01∶00(3.89%)和04∶00~05∶00(3.89%),雌、雄成虫移动行为日节律所占比例在03∶00~06∶00和补充营养行为日节律在03∶00~05∶00差异显著;成虫各行为分配频次最多的是停息行为,远高于其它行为,且各行为所占比例差异极显著,但雌、雄成虫之间无显著差异;雌、雄成虫运动行为几乎全部发生在暗期,且在不同时间段无显著差异;光、暗期各行为活动发生的比率差异显著;在暗期不同时间段,除雌蛾的移动行为、雄蛾的补充营养行为和交配行为无显著差异外,其它各种行为均差异显著。表明斜纹夜蛾雌、雄配对后移动、静息、补充营养、产卵和交配行为受成虫日龄影响较大,也受性别影响,表现出明显的日节律性。     

南美斑潜蝇成虫活动规律的观察

应用黄板法对南美斑潜蝇活动特性进行观测。结果表明,南美斑潜蝇在作物顶端层飞翔种群数较高,在此层面黄板诱集成虫数量最大。在干热季南美斑潜蝇的日活动高峰在８∶００～１０∶００和１８∶００～２０∶００,成虫量与日气温呈负相关。     

The occurrence of the avian schistosome Allobilharzia visceralis Kolákrová, Rudolfová, Hampl et Skirnisson, 2006 (Schistosomatidae) in the tundra swan, Cygnus columbianus (Anatidae), from North America

Twelve tundra swans, Cygnus columbianus (Ord), from Nevada and one from New Mexico were collected and examined for schistosomes. Mature worms, determined as Allobilharzia visceralis, were found in 92% of the swans, in the inferior mesenteric vein of the large intestine and its branches. In 12 cases, there was endophlebitis of the inferior mesenteric vein. The morphology of the worms is consistent with the recently described genus Allobilharzia. Placement in this genus was confirmed also by phylogenetic analysis of nuclear 28S, 18S and, internal transcribed spacer (ITS) ribosomal DNA (rDNA), and mitochondrial cytochrome oxidase I (CO1) sequences. Data further suggest the worms are con-specific with the European A. visceralis, the only described species of the genus and which was found to be the sister taxon to the most diverse avian schistosome genus, Trichobilharzia. This is the first report of a schistosome infection from native swans in North America.     

Spatial variability of leaf wetness under different soil water conditions in rainfed jujube(Ziziphus jujuba Mill.) in the loess hilly region,China

Leaf wetness provides a wide range of benefits not only to leaves,but also to ecosystems and communities.It regulates canopy eco-hydrological processes and drives spatial differences in hydrological flux.In spite of these functions,little remains known about the spatial distribution of leaf wetness under different soil water conditions.Leaf wetness measurements at the top(180 cm),middle(135 cm),and bottom(85 cm)of the canopy positions of rainfed jujube(Ziziphus jujuba Mill.)in the Chinese loess hilly region were obtained along with meteorological and soil water conditions during the growing seasons in 2019 and 2020.Under soil water non-deficit condition,the frequency of occurrence of leaf wetness was 5.45%higher at the top than at the middle and bottom of the canopy positions.The frequency of occurrence of leaf wetness at the top,middle and bottom of the canopy positions was over 80%at 17:00?18:00(LST).However,the occurrence of leaf wetness at the top was earlier than those at the middle and bottom of the canopy positions.Correspondingly,leaf drying at the top was also latter than those at the middle and bottom of the canopy positions.Leaf wetness duration at the middle was similar to that at the bottom of the canopy position,but about 1.46-3.01 h less than that at the top.Under soil water deficit condition,the frequency of occurrence of leaf wetness(4.92%-45.45%)followed the order of top>middle>bottom of the canopy position.As the onset of leaf wetness was delayed,the onset of wet leaf drying was advanced and the leaf wetness duration was shortened.Leaf wetness duration at the top was linearly related(R²>0.70)to those at the middle and bottom of the canopy positions under different soil water conditions.In conclusion,the hydrological processes at canopy surfaces of rainfed jujube depended on the position of leaves,thus adjusting canopy structure to redistribute hydrological process is a way to meet the water need of jujube.     

EFFECT OF CULTIVATION ON THE NUMBERS OF VIABLE WEED SEEDS IN SOIL

Summary. In a 6-year experiment with a naturally occurring population of viable weed seeds, the numbers in the top 9 in. of soil decreased exponentially from year to year in the absence of further seeding. The rates of loss were equivalent to 22% per year in undisturbed soil, 30% per year on plots dug twice a year (March and September) and 36% per year on those dug four times a year (March, June, September, December). Seed numbers of individual species also decreased exponentially, although not all at the same rates.
On the dug plots, the numbers of seedlings that emerged each year decreased exponentially once the regimes had become established. The proportions of the viable seeds which gave rise to seedlings in the course of a year were 7 % on plots dug twice and 9 % on those dug four times a year; although there was some variation, these proportions remained much the same from year to year. On undisturbed soil the number of seedlings that emerged declined rapidly, and in the 4th year represented no more than 03% of the viable seeds still present in the top 9 in. of soil.