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31.
树种枝叶微观结构对树种燃烧性的影响研究 总被引:3,自引:1,他引:3
选择具有不同抗火能力的亚热带树种来研究树叶和树枝的微观组织结构与燃烧性的关系,分别测定木荷、茶树、油茶、苦槠、女贞、石楠、日本珊瑚树、枇杷、杉木和马尾松等10个树种叶片、叶脉和树枝的组织比,并利用锥形量热仪测定样品的阻火性。结果发现,树叶构造对燃烧性有影响,阔叶树种的树叶结构有利于水分的传输与蒸散,叶脉中木质部比重越大,越有利于水分的传输;海绵组织,栅栏组织与火发生指数之间存在显著的回归关系,茶树、木荷的海绵组织,栅栏组织比值高,抗火能力强。树枝的燃烧性与其结构密切相关。特别是树枝的抗火性与其导管所占比例正相关,木荷、日本珊瑚树的导管比重大,传输水分的能力强,抗火烧能力强。 相似文献
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2种忍冬致病镰刀菌的生物学特性研究 总被引:1,自引:0,他引:1
为了明确忍冬根腐病的发生规律,以从忍冬根腐病株病根分离到的2种致病镰刀菌菌株FQ3(Fusarium solani species complex)、FQ4(Fusarium incarnatum-equiseti species complex)为研究对象,考察了其生物学特性。结果表明,菌株FQ3最适生长温度为30℃,最适产孢温度为35℃,最适生长pH值为9,最适产孢pH值为7~10,全黑暗条件最有利于菌丝生长和产孢,生长最适碳、氮源分别为乳糖和甘氨酸,产孢最适碳、氮源分别为葡萄糖和硝酸钠;菌株FQ4最适生长温度为25~30℃,最适产孢温度为30℃,最适生长pH值为7~10,最适产孢pH值为9,半光照条件有利于其生长和产孢,生长最适碳、氮源分别为蔗糖和酵母,产孢最适碳氮源分别为果糖和酵母。除温度处理外,菌株FQ3在所有参试条件下,菌丝生长速度及产孢量均明显高于菌株FQ4。 相似文献
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从整地、品种选择、苗木定植、树体管理、病虫害防治、采收、埋土越冬等方面介绍了半干旱气候区青铜峡市酿酒葡萄提质增效的栽培技术。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):446-459
The mean tree height of 73 forest stands in a 1000 ha forest area was determined from canopy heights generated by automatic image matching using a digital photogrammetric workstation and digitized panchromatic aerial photographs with a scale of 1:15 000. First, the mean height of each stand was computed as the arithmetic mean of the quantile corresponding to the 75th percentile of the distribution of the canopy heights from the image matching within square grid cells with cell sizes of 236-400 m2. The mean heights from the image matching underestimated the true heights by 5.42 m. Secondly, field-measured mean tree heights of 165 georeferenced sample plots distributed systematically throughout the 1000 ha forest area were regressed against the mean heights derived from the image matching. The regression equations were used to predict the mean heights of the 73 stands. In very young forest stands, the predicted mean heights overestimated the true heights by 0.4 m and the precision was 0.9-1.0 m. In young and mature stands, the average difference between predicted height and ground-truth ranged between -1.6 and 0.5 m, and the precision ranged from 1.1 to 2.1 m. 相似文献
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盘叶忍冬与台尔曼忍冬夏季主要光合特性的比较 总被引:3,自引:0,他引:3
研究了盘叶忍冬及台尔曼忍冬夏季的主要光合特性。结果表明: 台尔曼忍冬单叶叶面积较大,但比叶重小, 单位面积的色素含量较低。盘叶忍冬的光饱和光合速率和气孔导度均显著低于台尔曼忍冬,两者的光饱和点分别为400μmol·m- 2 ·s- 1和1 200μmol·m - 2 ·s- 1左右。此外, 二者的净光合速率日变化均为单峰曲线, 峰值分别出现在8: 00和10: 00。在本研究中两种忍冬的最大光化学效率差异较小, 但中等和强光条件下盘叶忍冬的实际光化学效率显著低于台尔曼忍冬, 而非光化学猝灭显著高于台尔曼忍冬。根据以上试验结果, 在我国北方露地栽培过程中台尔曼忍冬较盘叶忍冬对光照强度的适应幅度宽, 所以前者可应用于开阔地、林缘及疏林下的绿化, 而后者适于栽种在林下等较荫蔽的环境中。 相似文献
39.
We examined whether recreational tree climbing (TC) activities would have positive social impacts and rejuvenate an outdoor activity center and surrounding community forest in central Japan. Our case study comprised 3800 adults and children participating in TC activities at the Jyokoji Outdoor Activity Center (JOAC) in Seto, Japan. We focused on 1393 adult participants whom we considered to be the decision makers regarding family recreation, and we explored both the social impacts of TC and various factors that contributed to and distracted from the overall experience. Qualitative and quantitative data indicated that elements such as age, gender, tree preferences, tree appreciation, tree education, and technical instruction influenced the enjoyment of recreational TC and the positive effects on tree climbers. Overall, the climbing program had positive social impacts for the community forest and contributed to local conservation initiatives. Our case study suggests that other areas can benefit from incorporating TC programs into community forest planning to complement aesthetic, ecological, and restoration benefits and provide a new venue for recreation and conservation awareness. 相似文献
40.
Francisco de Assis Alves Mourão Filho Erick Espinoza-Núñez Eduardo Sanches Stuchi Edwin Moisés Marcos Ortega 《Scientia Horticulturae》2007
Vegetative growth, yield, and fruit quality of ‘Fallglo’ and ‘Sunburst’ mandarins on ‘Rangpur’ lime, ‘Swingle’ citrumelo, ‘Orlando’ tangelo, and ‘Cleopatra’ mandarin were evaluated under subtropical climate of Northern São Paulo State, Brazil, from 2000 through 2006 harvest seasons. ‘Fallglo’ mandarin trees had the highest cumulative yield on ‘Rangpur’ lime, and the smallest on ‘Swingle’ citrumelo and ‘Orlando’ tangelo. Plants of this cultivar had the highest yield efficiency on ‘Rangpur’ lime, and the lowest on ‘Orlando’ tangelo. ‘Sunburst’ mandarin trees began to bear fruits later than ‘Fallglo’ mandarin trees, with no differences in yield induced by the rootstocks. ‘Cleopatra’ mandarin induced the most vigorous growth in ‘Fallglo’ mandarin as compared to plants on ‘Swingle’ citrumelo. On the other hand, the largest trees of ‘Sunburst’ mandarin were registered on ‘Orlando’ tangelo, and the smallest on ‘Rangpur’ lime. ‘Sunburst’ mandarin had higher alternate bearing than ‘Fallglo’ regardless the rootstock. Fruit weight and juice content were not affected by the rootstock. These two mandarin scion cultivars may be considered adequate alternatives to produce good fruit quality for the fresh fruit market. ‘Cleopatra’ mandarin and ‘Rangpur lime are suitable rootstocks for ‘Fallglo’ mandarin, whereas all rootstocks evaluated are adequate for ‘Sunburst’ mandarin. 相似文献