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21.
ARMIN KEUPER 《Bioacoustics.》2013,22(4):287-306
ABSTRACT

The mechanism of sound production in tettigoniids is examined by applying the method of ‘cepstrum’ analysis to insect calls. The power cepstrum is defined as the inverse Fourier transform of the logarithmic power spectrum. This analysis shows that the tettigoniid sound signal is a convolution in time of probably two components. The first is caused by the initial impact of teeth of the stridulatory file on the left wing against the plectrum on the right wing (termed the input pulse); the second is caused by the oscillating properties of the tegmina (these being a function of the intrinsic frequencies of dorsal fields and mirror and their damping properties). In the cepstrum each component appears as a varying number of peaks. The tooth impacts cause a very low quefrency peak probably representing the time in which the two tegmina are in contact during each impact and high quefrency peaks representing the impulse repetition rate. The oscillating properties of the tegmina cause two major quefrency peaks which can be clearly related to the size of the dorsal fields and of the mirror respectively, and therefore to their intrinsic frequencies. The high damping factor of the tegmina together with the transient shape of the tegminal input pulse causes a strong time limitation of the impulses and is therefore responsible for the broad frequency bands occurring in the power spectra of the tettigoniid songs. The impulse generation of a synthetic tettigoniid song is discussed.  相似文献   
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We examined the content of the coelenteron of Oulactis orientalis, Cnidopus japonicus, and Aulactinia sp. (family Actiniidae) inhabiting the intertidal area of Shikotan and Kunashir Islands (South Kuril Islands). The feeding characteristics (food spectrum, the index of filling of the coelenteron, the index of food similarity of the species, occurrence frequency, the index of trophic importance, and the proportions of certain components in the food pellet) allowed us to determine that the examined species are euryphagous.  相似文献   
25.
Traditional Mediterranean diet includes the halophyte Crithmum maritimum L. (Apiaceae) which can be found in the coastline of the Balearic Islands but also inland. Both areas differed in the environmental conditions, mainly in salinity which can affect the oxidative status of this species. The aim was to evaluate the antioxidant enzyme activities, polyphenols and the lipid peroxidation in leaves of wild C. maritimum growing in a natural coastal area influenced by marine salinity and an inland area without marine influence. The activities of the antioxidant enzymes catalase, superoxide dismutase and glutathione peroxidase as well as polyphenol and reduced glutathione content were significantly higher in the samples from coastline population, whereas no significant differences were found in glutathione reductase activity and in malondialdehyde levels. The production of H2O2 was also significantly higher in the population from coastline. In conclusion, C. maritimum adapt their antioxidant defense machinery to the different salinity conditions, avoiding the instauration of oxidative stress.  相似文献   
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为了解红厚壳(Calophyllum inophyllum)的抗逆特性,对西沙群岛自然生长的红厚壳叶片的形态解剖、生理生态、以及叶片和适生土壤的元素含量进行了研究。结果表明,红厚壳是阳生性植物,其上表皮厚,海绵组织发达且栅栏组织排列紧密,气孔排列松散且密度小(24.40 mm~(-2)),有利于叶片保水抵御干旱。叶片的叶绿素a、b含量低(分别为0.87和0.43 mg g~(-1)),表明红厚壳具适应强光环境的能力。叶片的MDA含量低(13.46 nmol g~(-1)),PRO含量高(127.89μg g~(-1)),SOD活性高(149.42 U g~(-1)),总抗氧化能力高(388.60 U g~(-1)),显示红厚壳能通过提高自身的抗氧化能力抵御膜脂过氧化伤害。红厚壳自然生长的珊瑚岛土壤较为贫瘠、营养元素含量低,但红厚壳植株体内具有较高的营养元素含量,表明红厚壳营养元素利用率高,对于贫瘠土壤具有很好的适应能力。因此,红厚壳具有较高的抗氧化胁迫能力和耐受干旱的能力,适宜生长在热带珊瑚岛等土壤贫瘠的生境,可以作为热带珊瑚岛防风固沙和植被恢复的工具种。  相似文献   
27.
《Journal of Asia》2019,22(4):1187-1188
The introduction of species by human action is one of the main causes of rarefaction and extinctions of species. This fact is especially relevant in insular ecosystems. Here, we reported for the first time the arrival of Tirumala limniace (Cramer, [1775]) from the Asian to European continent. A single specimen was recorded in the Balearic Islands, which a large list of introductions around their history. Some reasons could explain the occurrence of this species into the islands, but the most likely are the cargo and nursery trade as well as the release of specimens for weddings and other social events as well as escaped from a private butterfly’s garden. This record highlights the importance of implementing early detection of introduced species in insular ecosystems.  相似文献   
28.
ABSTRACT

By employing comparative morphology and anatomy as well as mitochondrial phylogenetics, we have identified three species of Landouria Godwin-Austen, 1918 in Timor-Leste. One of these species is identified as L. cf winteriana (Pfeiffer, 1842), a species originally described from Java, but considered widespread throughout the Indonesian archipelago. The two other species are newly described as L. timorensis n. sp. and L. montana n. sp., respectively. Landouria timorensis n. sp. is similar to L. winteriana, but differs by a smaller shell and details of its penial morphology. Landouria montana n. sp. is only found at higher altitudes and is readily distinguishable by its distinctive shell. A mitochondrial phylogeny reveals L. omphalostoma from Yunnan as the sister lineage of all Sunda Islands species. Based on this observation, we maintain the systematic placement of the Sunda Islands species in Landouria despite some minor differences in their genital anatomy. Furthermore, our phylogeny demonstrates that the East Asian genus Aegista Albers, 1850 is the probable sister taxon of Landouria. However, we reject the proposal by Hirano et al. ([2014] Substantial incongruence among the morphology, taxonomy, and molecular phylogeny of the land snails Aegista, Landouria, Trishoplita, and Pseudobuliminus (Pulmonata: Bradybaenidae) occurring in East Asia. Molecular Phylogenetics and Evolution 70, 171–181) to synonymise both genera based on their markedly distinct reproductive anatomy.  相似文献   
29.
舟山群岛生态系统健康与旅游经济协调发展评价   总被引:1,自引:0,他引:1  
周彬  赵宽  钟林生  陈田  虞虎 《生态学报》2015,35(10):3437-3446
在界定生态系统健康与旅游经济协调发展定义的基础上,构建了海岛目的地生态系统健康和旅游经济协调发展评价的指标体系,采用改进的TOPSIS法对2000—2012年舟山群岛生态系统健康和海岛旅游业的协调发展状况进行了定量评价,运用障碍度模型对其协调发展的障碍因素进行了分析,并使用Logistic模型对2013—2015年协调发展状态进行了预测。研究表明:(1)2000—2012年,舟山群岛海岛生态系统健康和旅游经济的静态协调度和动态协调度总体均呈持增加趋势,静态协调度由0.6453增加到0.7301,动态协调度由0.6453增加至0.6874;(2)2000—2012年,舟山群岛生态系统健康和旅游经济由初级协调发展型向中级协调发展型演化,其中2000—2007年为初级协调发展型,2008—2012年为中级协调发展型;(3)海洋经济占GDP比重、近海海域环境功能区达标率、环保投入占GDP比重、公路网密度、城镇化率是影响舟山群岛生态系统健康和旅游经济协调发展的主要障碍因子;(4)2013—2015年,舟山群岛生态系统健康和旅游经济的静态协调度预测值为0.8335、0.8442和0.8543,动态协调度的预测值为0.6885、0.6916和0.6947,说明两者的协调发展状态将持续改善。  相似文献   
30.
基于变权模型的舟山群岛生态安全预警   总被引:4,自引:0,他引:4  
生态安全预警是生态安全研究的重要内容,对维护区域生态安全具有重要的指示意义.本文以浙江省舟山群岛为例,基于驱动力、压力、状态、影响、响应(DPSIR)框架模型构建了生态安全预警指标体系,使用变权模型对2000-2012年舟山市生态安全的预警等级进行测度,并使用马尔科夫预测方法对2013-2018年生态安全警情进行了预测.结果表明:变权模型能够有效地满足舟山群岛生态安全动态预警研究需要;2000-2012年,舟山群岛生态安全预警指数由0.286波动上升至0.484,警度等级从“重警”演变为“中警”,指示灯由“橙灯”演化为“黄灯”;2013-2018年,舟山群岛生态安全预警等级预测结果为“中警”,指示灯为“黄灯”.研究结果可为维护舟山群岛生态安全提供参考.  相似文献   
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