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991.
The amount of time needed to process samples with large numbers of terrestrial invertebrates in the laboratory has been a long‐standing obstacle impeding progress in invertebrate conservation biology and applied ecology. Laboratory subsampling of samples with large numbers of invertebrates is one method that saves time and reduces processing cost. In this study, a laboratory vacuum processing technique, consisting of a vacuum pump, aspirator and voice recognition software, was compared with a subsampling technique, and a conventional whole sample counting method. Vacuum processing was the most efficient technique; on average, more than five times more insects were processed per minute compared with whole sample counting and subsampling techniques. Differences in efficiencies among techniques were affected by trap type and invertebrate abundance. The vacuum technique was most efficient when processing high abundance pitfall trap samples, and was less efficient in processing pan trap samples that had invertebrates entangled by algae and other materials. Caution should be exercised when using the technique on soft‐bodied or poorly preserved specimens; a subsampling technique may be more appropriate in these cases, especially if specimens must be identified to genus or species level at a later time. The efficiency of the vacuum technique is reduced relative to the amount of time it takes to locate invertebrates in a sample; therefore, the technique does not save substantial time when processing samples with large amounts of substrate or debris, such as is the case with some aquatic invertebrate samples. However, if flotation or another method that separates invertebrates from other materials is used first, then the vacuum method would be useful for these types of samples as well.  相似文献   
992.
993.
<正>小型兽类包括食虫目(Insectivora)、啮齿目(Rodentia)、翼手目(Chiroptera)、兔形目(Lagomorpha)等,物种数量多,分布广,适应能力强,对环境变化敏感,因此其群落组成和种群数量变化可较好地反映生境变化的质量和人类活动的干扰程度(肖治术等,2002;李俊生等,2003;仝磊和路纪琪,2010)。小型兽类多样性一直是生物多样性和生态环境监测与评价的重要指示类群之一(周立志和马勇,2002)。统计动物毛发、粪便、巢穴、叫声、足迹等动物痕迹以及直接观察等方法已被广泛用于兽类物种监测和种群密度估计(Eberhardt and Van Etten,1956;Bider,1968;Gannon  相似文献   
994.
Activities involving fauna monitoring are usually limited by the lack of resources; therefore, the choice of a proper and efficient methodology is fundamental to maximize the cost–benefit ratio. Both direct and indirect methods can be used to survey mammals, but the latter are preferred due to the difficulty to come in sight of and/or to capture the individuals, besides being cheaper. We compared the performance of two methods to survey medium and large-sized mammal: track plot recording and camera trapping, and their costs were assessed. At Jataí Ecological Station (S21°31'15"–W47°34'42"-Brazil) we installed ten camera traps along a dirt road directly in front of ten track plots, and monitored them for 10 days. We cleaned the plots, adjusted the cameras, and noted down the recorded species daily. Records taken by both methods showed they sample the local richness in different ways (Wilcoxon, T = 231; p ;; 0.01). The track plot method performed better on registering individuals whereas camera trapping provided records which permitted more accurate species identification. The type of infra-red sensor camera used showed a strong bias towards individual body mass (R 2 = 0.70; p = 0.017), and the variable expenses of this method in a 10-day survey were estimated about 2.04 times higher compared to track plot method; however, in a long run camera trapping becomes cheaper than track plot recording. Concluding, track plot recording is good enough for quick surveys under a limited budget, and camera trapping is best for precise species identification and the investigation of species details, performing better for large animals. When used together, these methods can be complementary.  相似文献   
995.
The occurrence of a kairomonal response of the parasitoid Anagyrus spec. nov. near pseudococci (Hymenoptera: Encyrtidae) to (+)‐(1R,3R)‐cis‐2,2‐dimethyl‐3‐isopropenyl‐cyclobutanemethanol acetate (PcA, namely, planococcyl acetate) and (S)‐(+)‐lavandulyl senecioate (LS), the respective female sex pheromones of its hosts, the citrus mealybug, Planococcus citri (Risso) and the vine mealybug, Planococcus ficus (Signoret) (Homoptera: Pseudococcidae) was investigated. Attraction to the pheromones was tested by employing pheromone traps in field trials and by static air olfactometer bioassays in the laboratory. Female wasps showed a significant response to LS, in both field and olfactometer experiments. No significant response was registered to the sex pheromone of P. citri. Despite the similarity between the structures of LS and its analogue (S)(+)‐lavandulyl isovalerate (LI), no significant response to the latter compound was observed. It seems that differences between the structures of the carboxylate moiety of the respective molecules (LS and LI) markedly affect the kairomonal attractiveness to the parasitoid. The kairomonal response of Anagyrus spec. nov. near pseudococci was neither influenced by the host habitat nor by the host species on which it developed. This suggested innate behaviour of Anagyrus spec. nov. near pseudococci, possibly derived from evolutionary relationships between the parasitoid and P. ficus. The practical implications of the results are discussed.  相似文献   
996.
997.
Mass spectrometry (MS) has the potential to revolutionize structural glycobiology and help in the understanding of how post-translation events such as glycosylation affect protein activities. Several approaches to determine the structure of glycopeptides have been used successfully including fast atom bombardment, matrix-assisted laser desorption ionization, and electrospray ionization with a wide variety of mass analyzers. However, the identification of glycopeptides in a complex mixture still remains a challenge. The source of this challenge is primarily due to the poor ionization efficiency and rapid degradation of glycopeptides. In this report we describe the use of a chip-based infusion nanoelectrospray ionization technique in combination with a recently developed linear ion trap for identification and characterization of glycosylation in complex mixtures. Two standard synthetic glycans were analyzed using multiple-stage fragmentation analysis in both positive and negative ionization modes. In addition, the high mannose type N-glycosylation in ribonuclease B (RNase B) was used to map the glycosylation site and obtain the glycan structures. We were able to map the glycosylation site and obtain the glycan structures in RNase B in a single analysis. The results reported here demonstrate that the fully automated chip-based nanoelectrospray linear ion trap platform is a valuable system for oligosaccharide analyses due to the unique MS/MS and MS(n) capability of the linear ion trap and the extended analysis time provided by the ionization technique.  相似文献   
998.
北京梨园绿盲蝽及其天敌的种群动态   总被引:1,自引:0,他引:1  
郭晨茜  王璇  杨宇晖  刘小侠  张青文 《昆虫学报》2013,56(12):1516-1522
【目的】调查研究梨园绿盲蝽Apolygus lucorum (Meyer-Dür)及其天敌的种群动态, 为梨园绿盲蝽的预测预报和科学防治提供理论依据。【方法】2012-2013年利用色板诱集法和目测法, 对北京市农林科学院林业果树研究所梨园的绿盲蝽及其天敌的种群动态进行了系统调查和分析。【结果】绿板调查结果显示, 绿盲蝽在梨园的发生有2个高峰期, 第1个峰值远高于第2个峰值, 主要发生高峰期为5月下旬至6月中旬。目测调查结果显示, 2012年, 绿盲蝽有两个发生高峰期, 5月中旬达到第1个峰值, 5月下旬达到第2个峰值; 2013年, 绿盲蝽仅有5月下旬一个发生高峰期。2012和2013年天敌主要发生高峰期均为6月上旬至下旬。梨园调查到的天敌主要为捕食类天敌, 包括蜘蛛和天敌昆虫, 其中天敌昆虫有7种隶属3目3科。天敌的优势种类为蜘蛛、 龟纹瓢虫、 异色瓢虫、 中华草蛉。【结论】天敌的发生与绿盲蝽有明显的时间和数量跟随关系。  相似文献   
999.
福建省白背飞虱前期迁入虫源分析   总被引:2,自引:0,他引:2  
近年来, 福建省白背飞虱Sogatella furcifera (Horváth)危害严重, 尤其2007年, 全省早稻白背飞虱特大发生, 迁入峰不但比常年偏早, 且虫量异常偏多。本文利用由美国国家大气与海洋局与澳大利亚国家气象局共同开发研制的大气质点轨迹分析平台模型HYSPLIT, 和气象图形分析显示软件GrADS对2007-2010年4-5月福建省白背飞虱早期主要迁入峰次进行了轨迹模拟, 并对2007年5月份的主要迁入过程进行了天气学背景分析。结果显示: (1) 福建省白背飞虱早期迁入虫源主要来自广东、海南省, 台湾省、 菲律宾仅在个别年份提供少量虫源, 非主要虫源地; (2) 低空急流与持续降水的配合是导致2007年白背飞虱集中降落的直接原因。2007年5月稻飞虱迁入同期, 福建850 hPa上空低空急流频繁, 5月份西太平洋副高比往年偏西、 偏强, 且北跳推迟, 使得华南地面准静止锋形成, 雨季延长; (3)2007年广东、 海南3月底至4月初的1代成虫迁入种群较多造成的田间2代白背飞虱虫源基数的增加是造成2007年福建白背飞虱迁入量增加的最根本原因。福建白背飞虱的主迁入虫量取决于两广早期田间虫源基数的多寡, 在副高偏强、 雨水较多年份, 提前对两广、 海南地区田间稻飞虱发生情况进行了解将有助于福建稻飞虱的预防与治理。  相似文献   
1000.
Coccolith fluxes were investigated by sediment trap studies in the West Caroline Basin, which is located in the equatorial western Pacific. The investigation was conducted from June 1991 to March 1992 at two water depths, 1592 and 3902 m, as part of the Northwest Pacific Carbon Cycle Study (NOPACCS) program. Two seasonal maxima of coccolith fluxes were observed during September–early October and late December–January. The average coccolith and coccosphere fluxes at the depth of the shallow trap were 1800×106 coccoliths m−2 day−1 and 1.9×106 coccospheres m−2 day−1, respectively. The flux of coccoliths followed the same trend as the total flux, and was closely correlated with the flux of organic matter flux. Florisphaera profunda, Gladiolithus flabellatus, Gephyrocapsa oceanica, Umbilicosphaera sibogae var. sibogae, Emiliania huxleyi, and Oolithotus fragilis were the most abundant species together comprising more than 85% of the total flora. Observed seasonal changes of the species composition of coccolith flora, as well as analysis of the R-mode cluster, revealed that during the summer, the assemblage was marked by the dominance of G. oceanica and U. sibogae. However, during the winter, the assemblage was dominated by E. huxleyi and O. fragilis. These assemblage changes were influenced by monsoonal events, which were observed off the New Guinea coast. F. profunda dominated the community in the shallow trap throughout most of the year; peak values of this species were recorded during the winter. The coccosphere assemblage was dominated by G. oceanica at both water depths. In the deep trap, the sedimentation pattern was similar to that observed at the shallow depth. Mean coccolith and coccosphere fluxes at the deep trap were 2000×106 coccolith m−2 day−1 and 0.08×106 coccospheres m−2 day−1, respectively. The increase in coccolith flux with water depth suggests a lateral influx. The estimated average daily mass of CaCO3 flux in coccoliths and coccospheres was 16.6 mg m−2 day−1 at the 1592 m trap and 17.9 mg m−2 day−1 at the 3902 m trap, respectively. These calculated values contributed only 23.3% to the total CaCO3 flux at the shallow trap and 27.9% at the deep trap.  相似文献   
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