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61.
2016年6月-2017年5月,采用红外相机陷阱法研究了四川贡嘎山国家级自然保护区兔狲Otocolobus manul的活动节律,以样线法和红外相机调查得到的兔狲分布点为数据源,采用最大熵(MaxEnt)模型预测了兔狲的适宜栖息地分布。结果显示:(1)兔狲分布在海拔3 780~4 956 m的灌丛、草甸和流石滩生境,其中87.2%的分布点位于海拔4 500 m以上;(2)日活动差异指数为0.071 2,昼行性指数为0.34,兔狲的活动高峰为05∶00-07∶00和20∶00-22∶00;(3)增强型植被指数2年最大值均值、海拔、平均日较差和气温年较差是影响兔狲栖息地选择的主要环境因子,兔狲偏好在海拔4 000 m以上、温差较大的高山流石滩生境活动,保护区兔狲的适宜栖息地面积为187 km^2,占保护区总面积的4.56%。本研究充实了兔狲的生物学、生态学资料,也为该物种的保护管理提供了参考资料。  相似文献   
62.
动物活动节律和时间生态位分化是动物行为在时间维度的分布, 是对时间资源利用的重要体现。动物活动节律受到环境因素和种间作用的影响, 因此, 了解动物活动节律以及时间生态位有助于揭示群落中同域分布物种时间资源利用的差异及共存机制。近10多年来, 红外相机技术在国内外野生动物监测研究中得到广泛应用, 积累了大量有时间记录的动物行为数据, 极大地促进了动物活动节律和时间生态位分化的深入研究。本文对动物活动节律研究以及应用红外相机数据研究动物活动节律的方法进行梳理, 采用核密度估计方法, 利用广东车八岭国家级自然保护区的红外相机监测数据, 分析了鸡形目鸟类的活动节律, 以阐述单物种和多物种的活动节律以及种间作用对动物日活动节律的影响。研究结果表明车八岭保护区白鹇(Lophura nycthemera)、白眉山鹧鸪(Arborophila gingica)和灰胸竹鸡(Bambusicola thoracica)等3个鸡形目物种之间存在不同程度的竞争, 物种间的日活动节律呈现中等程度的重叠。最后, 针对动物活动节律分析方法应用的建议及影响因素进行讨论, 希望为国内动物活动节律研究提供参考。  相似文献   
63.
庞泉沟国家自然保护区森林群落木本植物种间关系的分析   总被引:8,自引:1,他引:7  
应用基于二元数据的χ2检验、方差比率法和基于数量数据的Pearson相关系数检验及Spearman秩相关系数检验等数量方法,研究了庞泉沟国家级自然保护区(东经111°22′~111°33′,北纬37°45′~37°55′)森林群落(海拔1 600~2 430 m)21个优势种的种间关系。结果表明:研究区域内森林群落优势种群的种间关系较为松散(χ20.95N<W<χ20.05N),种的分布相对独立,森林群落总体处于稳定阶段;但局部地段优势种群间存在着一定程度的竞争。位于山体中下部的群丛组Ⅰ、群丛组Ⅱ的总体关联性存在一定程度的负关联,但未达到显著水平; 位于山体上部的群丛组Ⅲ的总体关联性为无关联,种间关系较为松散。随着海拔的升高,三个群丛组的联结指数(VR)呈上升趋势,χ2检验显著率和Spearman秩相关检验的正负关联比有所增加,负显著率都明显下降,正显著率有升高的趋势,说明随着海拔的升高,种间关系表现为无关联,森林群落也趋于稳定。应用方差比率法与χ2检验、Pearson相关系数检验和Spearman秩相关系数检验较为清晰地揭示了庞泉沟自然保护区森林群落的种间关系。这四种方法可以互相弥补彼此的不足,结合使用效果更好。本研究结果支持随着群落演替进程的发展,群落结构及其种类组成将逐渐趋于完善和稳定,群落种群总体种间关系也将向着无关联发展的观点。  相似文献   
64.
付伟  赵遵田  郭守玉 《菌物研究》2007,5(3):176-182
通过分析近10年在PNAS,Nature及Science上发表的涉及地衣的文章,并结合相关文献,总结了当前地衣学研究的主要方面及重要进展。对地衣化石、共生进化、系统发育、共生藻、功能遗传学、地衣生殖及生态生理学等领域取得的成果进行了概述,同时展望了中国地衣学研究的发展前景。  相似文献   
65.
Local communities often conserve nearby natural areas to support recreational activities and other benefits these areas provide. Areas protected by local communities could contribute to wider efforts to achieve large-scale conservation goals, such as biodiversity protection, provided the ecological conditions on-site are compatible with achieving these goals. To explore the potential contribution of locally established protected areas, we focus on areas protected by local communities in California, USA, using ballot initiatives, a form of direct democracy. We compare the ecological condition of wooded habitat on protected areas funded by local communities through the ballot box to that of similar habitats on protected areas funded by a state conservation agency. As an indicator of ecological condition, we focus on coverage by exotic plant species. We examine whether protected area characteristics or aspects of human-mediated onsite disturbance related to recreational use explain exotic plant cover found on each type of protected area. Exotic plant cover did not differ between areas protected by local communities and those protected by our larger scale conservation actor. Instead, elevation was the best predictor of exotic plant cover. Our results suggest protected areas established by local communities may be in no worse a condition than those established by a state public agency and warrant inclusion when tracking progress towards large-scale conservation goals for protected areas.  相似文献   
66.
Habitat banking in its many iterations is an established and popular mechanism to deliver environmental offsets. The United States can look back at over 30 years of banking experience with the underlying framework and policies being consistently updated and improved. Given the increased demand in habitat banking, we provide insights into how bank area capacity is distributed across the United States for four different bank targets (wetlands, streams, multiple ecosystems, species) based on information extracted from the Regulatory In-lieu Fee and Bank Information Tracking System, as well as, estimating future capacities and area reserves through a predictive modeling approach based on data from the past 26 years. Future predictions indicate a decrease in available reserves for banks targeting wetlands or multiple ecosystems, with potential bottlenecks relating to large reserves being limited to the southeast and release schedules not catching up to the current and anticipated demand. Banks targeting species or streams are predicted to meet future demand, with species banks (conservation banks) following a different legislative and operational approach based on the listing of endangered species and pro-active approaches with anticipated future demand. Most current reserves for all four bank types are restricted to very few service areas with around one-third of all bank areas still awaiting release, limiting their availability on a broader scale. Strategic planning networks are necessary to meet future demand on a national scale and to identify areas suitable for banking or likely to experience future environmental or developmental stress.  相似文献   
67.
Determining effects of landscape-level conservation strategies is needed, yet a challenging and costly endeavour. The aim of this study was to evaluate the effects of landscape-level conservation strategies in forests on biodiversity and provision of two ecosystem services (recreation and water quality). Specifically, we focused on the spatial allocation of unmanaged areas in production forests and different levels of “land sharing” or “land sparing”. They were represented through seven scenarios constructed for a boreal managed forest landscape in central Sweden. All scenarios had the same total level of conservation effort, but they differed in the combinations of sizes of unmanaged areas and how these areas were spread in the landscape. In one scenario, this was complemented with extended rotation of production areas. Experts (researchers in relevant fields) assessed these scenarios for overall biodiversity, recreation, and water quality. We used the Delphi technique: experts filled out an online survey individually in two rounds. In the second round they were familiarized with anonymized responses of others from the previous round. There was little agreement between experts whether concentration of unmanaged areas in one part of the landscape or dispersion of them around the entire area is more beneficial, for biodiversity as well as for the two ecosystem services. The explanation of the opinions given by biodiversity experts were based on different ecological theories resulting in different conclusions (mainly habitat complementation vs. metapopulation ecology). A few large unmanaged areas were considered more beneficial for biodiversity than many small areas. The main argument was that long-term species persistence becomes higher with larger areas. For recreation and water quality, there were almost no differences in estimates between these two strategies. One “land sharing” approach, retention trees, received the lowest score. The second “land sharing” approach, extended rotation, was scored higher, especially regarding recreation. This may be because extended rotations generate features of high recreational value, such as mature, thinned forests with not so much dead wood. Conclusively, we suggest a strategy of mixed conservation measures, with considerable efforts directed towards establishing and maintaining large unmanaged areas.  相似文献   
68.
谢凡  鲁碧耕  油志远  李刚  张惠  杨孔  杨楠 《四川动物》2022,41(1):107-120
鸟类多样性研究是国家级自然保护区的重要工作。2020年6月—2021年5月,采用样线法和样点法,调查了四川格西沟国家级自然保护区的鸟类多样性。结果显示:结合历史文献资料,保护区共有鸟类19目56科249种。其中,国家一级重点保护动物10种,国家二级重点保护动物35种,中国特有种11种。居留型以留鸟为主,共156种(62.65%),其次是夏候鸟60种(24.10%)、旅鸟19种(7.63%)、冬候鸟14种(5.62%)。区系组成以东洋界为主,共116种(46.59%),古北界103种(41.37%)、广布种30种(12.04%)。各生态系统中森林和灌丛生态系统Shannon-Wiener指数最高,其他生态系统最低,森林和灌丛生态系统的Sorenson相似性指数最高;夏、秋季的Shannon-Wiener指数和Pielou均匀度指数最高,冬季最低。建议保护区建立长期监测体系,并持续开展鸟类保护宣传活动,加大巡护和管控力度,降低保护区内的人为干扰,同时注重鸟类所利用栖息地的保护。  相似文献   
69.
西双版纳保护区植物根际细菌的筛选及其促生能力研究   总被引:2,自引:1,他引:1  
【背景】西双版纳保护区具有丰富的生物多样性,而该区域植物根际细菌特别是放线菌及其促生能力相关报道较少。【目的】从西双版纳保护区根际土壤中筛选出植物根际促生菌,并检测其促生能力。【方法】采用5种不同培养基筛选出植物根际促生菌并通过16S rDNA序列分析进行分类学鉴定,运用Salkowski法测定菌株产IAA的能力,CAS法测定菌株产铁载体能力,钼锑抗显色法测定菌株的解磷能力,CMC-Na法测定菌株产纤维素酶能力和改良的Young法测定产淀粉酶能力,综合评价所得菌株的促生能力。【结果】从土样中分离纯化得到14株典型促生菌,经鉴定分别归属于链霉菌属(Streptomyces)、诺卡菌属(Nocardi)、杆菌属(Bacillus)、中华根瘤菌属(Ensifer)、中慢生根瘤菌属(Mesorhizobium)、固氮螺菌属(Azospirillum)和狭单胞菌属(Stenotrophomonas)。其中菌株B433产吲哚乙酸的能力在培养12 d时达到最大值9.23 mg/L;菌株B351、B453、B546这3株菌株产铁载体的能力较强,其Su80%,最高可达86.67%,强度为+++++;菌株B541的解磷能力最强,磷酸根的浓度达到9.79 mg/L;菌株B442综合产纤维素酶能力最强为31.86 U/mL;菌株B412淀粉酶活力为16.07 U/mL。【结论】西双版纳保护区植物根际土壤促生细菌种类丰富,且具有较强的广谱促生能力,有潜在的开发价值,本研究可为此地的微生物资源开发提供可靠的菌株资源依据。  相似文献   
70.
Lombard  A.T.  Hilton-Taylor  C.  Rebelo  A.G.  Pressey  R.L.  Cowling  R.M. 《Plant Ecology》1999,142(1-2):35-55
The Succulent Karoo biome is home to the world's richest succulent flora. It has approximately 1954 endemic plant species, and is the only semi-arid region to qualify as a hotspot of global significance. Despite its importance, only 2% of the biome is currently protected. Based on its flora, the biome can be divided into 12 bioregions, reflecting its high compositional turnover in relation to environmental and geographical gradients. Only three of these bioregions (the Gariep Centre, the Namaqualand Rocky Hills and the Tanqua Karoo) contain National Parks, and three contain large (over 10000 ha) provincial reserves (the Gariep Centre, the Namaqualand Rocky Hills and the Little Karoo). The current reserve system does little to conserve biodiversity, with only one reserve significantly conserving Red Data Book (RDB) plant diversity. Using a RDB plant species database of 3874 records at a quarter degree scale (QDS = 15×15), we used hotspot analyses and iterative reserve selection algorithms to identify possible locations for future reserves. The hotspot analysis and iterative analyses yielded similar results for the top 11 QDS, mainly due to very high local endemism. Also because of the local endemism and the high species turnover within the biome, the real-world iterative algorithm (starting with the seven already reserved QDS) selected a very large total number of QDS (59% of the total in the biome) to conserve all RDB species. As a possible alternative to conservation planning based on QDS, we also assessed priorities at the scale of bioregions, but showed that representation at this geographic level misses important areas defined at a finer scale. We suggest that if the objective is to maximise the retention of RDB species in the landscape (to pre-empt extinction by scheduling the allocation of limited conservation resources), at least the top 5% of QDS (n=11) selected by the iterative procedure, and identified as the core conservation sequence by analysis of endemicity and threat, should be given priority for reservation. Less extensive and, in some cases, less formal conservation action can be applied to QDS later in the sequence, based on species-specific monitoring and action plans. Of the 11 core areas, four fall in a node centred on the Vanrhynsdorp Centre, two fall in a node centred on the Kamiesberg, and the remaining five are isolated. With existing reserves, the core areas capture 50% of the RDB flora in 8% of the biome.  相似文献   
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