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381.
This study investigates associations between perceived sensory dimensions (PSDs) of urban green spaces (UGSs) and adults’ perceived restoration, stress, and mental health. Data were collected through surveys with 426 adults in 2019 in seven different UGSs in Aydın, Turkey. The PSDs of UGSs (nature, serene, space, rich in species, social, prospect, culture, and refuge) were evaluated and rated by two professional landscape architects. The perceived restorativeness (being away, fascination, coherence, and compatibility) was measured with the Perceived Restorativeness Scale, and health indicators (stress, mental health, mental health diagnosis, mental health treatment, general health, and quality of life) were measured with self-reported questions. Multivariate multiple regression analyses were conducted to examine associations controlling for confounding factors. Four of the eight PSDs were analyzed due to multicollinearity issues in the study. Regression analyses showed that ‘nature’ was positively associated with perceived restorativeness, stress, and mental health, while ‘refuge’ was only positively associated with perceived restorativeness. On the other hand, ‘serene’ was negatively associated with perceived restorativeness. Whereas ‘rich in species’ was found to be negatively associated with perceived restorativeness and positively associated with mental health diagnosis. In addition, findings showed that frequency of and duration of UGSs visit were negatively associated with perceived restorativeness. The findings suggest that providing characteristics of ‘nature’ and ‘refuge’ in UGSs may provide restorative effects and mental benefits to adults. However, unexpected results suggest that further research is needed before using these characteristics as a tool by landscape architects and city planners.  相似文献   
382.
The conservation of historic gardens is crucial for safeguarding monumental, aesthetic, historical, ecological and economic values in many countries of the World, as well as associated services, such as carbon stock, microclimate and water regulation, biodiversity conservation, pollution removal, and recreation. In historic gardens, architectural and sculpture elements coexist with an abundant plant component, which is currently often precarious due to senescence processes occurring nowadays. Unhealthy plants and reduced structural stability of trees represent a threat for both garden artistic structures and buildings, as well for the visitors’ safety. Awareness in garden managers about the most relevant and current threats is necessary for garden conservation. This review, through a global survey of the literature since 1990, addresses two main questions (1) which are the most relevant threats on historic gardens vegetation as affected by environmental, biological and anthropogenic causes, and how do they impact on monuments? (2) Which are related strategies to counteract these threats? Regarding the whole analysed period, the impact of the biotic component on monuments was the most discussed threat; in recent years a growing concern on the effects of climate change and pathogens and pests on historic garden plants also emerged. Strategies to address current and future challenges of historic gardens are hereby identified from experiences reported in worldwide literature and discussed. Best practices are collected in tables to provide managers of historic gardens with a valuable tool and guide to conserve and enhance their value. Due to the heterogeneity of the threats to be addressed, a multidisciplinary approach to ensure the conservation of historic gardens is recommended.  相似文献   
383.
The near-to-nature urban forestry concept and practices are widely recognized for urban greening, urban ecosystem restoration, urban greenspace management for biodiversity conservation and ecosystem services provision. However, the regeneration and succession of urban vegetation are rarely studied due to the complex settings of the urban environment. To this end, we conducted a large-scale field investigation in the metropolitan area of Beijing, China to explore the spatial variations in plant species composition and diversity in soil seed banks, and their similarity to the aboveground vegetation to assess the potential of urban plant regeneration. Overall, 657 vegetation and soil sampling plots from 219 grids, measuring 2 km × 2 km each, were investigated within two perpendicular 10 km wide transects running across the urban center in north-south and east-west directions within the 6th Ring Road of the city. We recorded a total of 102 plant species in soil seed banks, including 13 tree species, 10 shrub species, and 79 herb species. We found that the soil seed bank species diversity and its similarity to that of the aboveground vegetation communities decreased significantly with the urbanization intensity. Higher urbanization intensity is typically associated with increased human management and a reduction in Greenspace Area (GSA). Soil seed bank species richness increased significantly when GSA exceeded 45 % and the similarity of species composition and diversity between soil seed banks and aboveground vegetation communities was the highest in forest parks. This suggests that habitats under forest park management are more conducive to plant regeneration. Soil seed bank species diversity first increased and then decreased significantly with increased distance to the city center, whereas the species similarity between the soil seed banks and the aboveground vegetation communities showed little change with the ring roads going out. The results of this study have important implications for further understanding the potential for urban vegetation regeneration and sustainability, which have significant implications for urban biodiversity conservation and restoration.  相似文献   
384.
陕西汉江流域是"南水北调"中线工程的主要水源地,属于国家重点生态功能区。研究流域内景观格局的时空变化特征、生态系统服务价值和景观生态风险的相关性,对保持流域内生态系统稳定性、保障流域生态安全具有指导意义。基于2000年、2005年、2010年、2015年、2020年陕西汉江流域5期土地利用数据,采用景观格局指数计算、生态系统服务价值评估、景观生态风险评估等方法,研究景观格局变化下生态系统服务价值、景观生态风险的时空演变机制及空间相关关系。结果表明:(1)2000—2020年,流域内景观格局斑块破碎程度降低、异质性和连通性减弱、多样性增加,各地类景观向复杂化方向发展;(2)研究时域内,研究区ESV总体增加5.23亿元,气候调节价值最高,占比41.70%,以较低和中等价值等级为主,占比约61.62%;(3)研究时域内,研究区ESR整体呈小幅减少趋势,降幅1.40%,以较低和中等生态风险等级为主,占比约61.55%;(4)陕西汉江流域生态系统服务价值与生态风险之间存在显著负向空间相关性。景观格局变化使陕西汉江流域生态系统服务功能升高,生态风险降低,两者空间自相关性减弱。  相似文献   
385.
为探究土壤质地对天然湿地土壤有机碳含量的影响,以鄱阳湖泗洲头湿地为研究对象,利用激光粒度分析仪测定苔草(Carex cinerascens)、南荻(Triarrhena lutarioriparia)、芦苇(Phragmites australis)、荻(Miscanthus sacchariflorus)和狗牙根(Cynodon dactylon)5种优势植被下的表层(0~20 cm)和下层(20~40 cm)土壤粒度组成,采用Folk-Ward公式计算土壤粒度参数,分析土壤粒度分布特征,利用结构方程模型(structural equation model,SEM)和Pearson相关性探讨土壤粒度组成与土壤有机碳的关系。结果表明,鄱阳湖泗洲头湿地土壤质地以粉黏土和砂壤土为主,分选性较差。粉黏土质地组成主要以粉粒(67.76%~79.28%)为主,平均粒径(Mz)为6.91Φ,粒度频率曲线为双峰或三峰分布;砂壤土质地组成主要以细砂(32.90%~56.55%)为主,Mz为3.00Φ,粒度频率曲线为单峰分布。粉黏土土壤有机碳含量为(10.52±3.86) g/kg,显著高于砂壤土土壤有...  相似文献   
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