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排序方式: 共有268条查询结果,搜索用时 15 毫秒
81.
82.
智能田间除草机器人是当代农业发展现代化、精细化、智能化的重要体现,对国家社会发展、环境保护等方面有着重要意义。为明确智能除草机器人关键技术与装备当前研究现状,从除草方式、苗草识别定位和智能导航方式等方面,总结梳理典型除草机器人的研究现状及作业方式;综述智能导航、苗草识别、除草执行系统关键技术的重要意义及研究进展;结合除草机器人具有作业环境复杂多变性、作业对象娇嫩性、使用对象特殊性、作业季节性的研究特点,指出当前关键技术的现存问题并阐释组合导航技术、复杂田间环境图像处理技术及杂草分类、株间除草末端执行机构研发及机械结构优化是未来发展趋势。 相似文献
83.
《Communications in Soil Science and Plant Analysis》2012,43(8):1083-1105
Changes in soil fertility indicators are mainly the result of management practices and usually influence crop yields over the long term. This study shows the effects of long-term wheat production management practices on exchangeable base cations and cation exchange capacity (CEC). Applied field treatments included two methods of straw management (unburned, burned), three methods of tillage (no tillage, stubble mulch, plowing), and two methods of weeding (chemical, mechanical). Samples were collected at six soil depths and analyzed for potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), and CEC. Burned wheat straw resulted in greater K and lower Ca concentrations compared to unburned wheat straw. No-tillage treatment increased K, Ca, Mg, Na, and CEC compared to both stubble mulch and plowing. Chemical weeding improved Na and CEC compared to mechanical weeding. The treatment combinations had positive influences mainly on CEC. Unburned straw and moldboard plowing with respect to burned straw and no tillage enhanced grain yield with 8%. 相似文献
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85.
S CHRISTENSEN H T SØGAARD† P KUDSK‡ M NØRREMARK§ I LUND¶ E S NADIMI¶ & R JØRGENSEN¶ 《Weed Research》2009,49(3):233-241
Site-specific weed control technologies are defined as machinery or equipment embedded with technologies that detect weeds growing in a crop and, taking into account predefined factors such as economics, take action to maximise the chances of successfully controlling them. In this study, we describe the basic parts of site-specific weed control technologies, comprising weed sensing systems, weed management models and precision weed control implements. A review of state-of-the-art technologies shows that several weed sensing systems and precision implements have been developed over the last two decades, although barriers prevent their breakthrough. Most important among these is the lack of a truly robust weed recognition method, owing to mutual shading among plants and limitations in the capacity of highly accurate spraying and weeding apparatus. Another barrier is the lack of knowledge about the economic and environmental potential for increasing the resolution of weed control. The integration of site-specific information on weed distribution, weed species composition and density and the effect on crop yield, is decisive for successful site-specific weed management. 相似文献
86.
基于后茬作物安全性的小麦除草专用肥研究 总被引:1,自引:0,他引:1
小麦除草专用肥是具有除草功能的药肥,经过几年的小麦除草专用肥营养配方和除草配方分步研究,优选出除草效果好、对后茬油菜安全的mz4-C6(基肥)和mz4-C1(追肥)两个小麦除草专用肥配方,其中mz4-C6(基肥)适合旱地施用,株防效达73.3%,鲜重防效达83.4%,小麦增产23.16%,后茬油菜增产4%;mz4-C1(追肥)适合水浇地施用,总株防效71.24%,小麦增产13.45%,后茬油菜增产27.25%。 相似文献
87.
稻田株间除草机构除草过程中伤秧影响的试验研究 总被引:1,自引:0,他引:1
稻田杂草是影响大米产量和质量的一个重要因素。鉴于化学除草的负面影响,机械除草技术一直是国内外科研攻关的重点,但如何降低除草过程中工作装置对秧苗的损伤和影响成为研究的难点。为此,对稻田机械式株间除草机构的主要因素的秧苗损伤情况进行了试验研究。试验在机插稻田进行,稻苗行间距28~31cm,株间距14~15cm。试验在秧苗移栽后7天左右进行,该时间为稻田第一个出草高峰期,试验采用二次旋转正交试验方法,应用Design-Expert进行试验分析,获得了株间除草主要工作因素机器前进速度、除草盘转速、除草深度之间单因子及交互作用对伤秧率的影响。移栽7天时,田间试验在保证除草率的前提下确定了低伤秧率株间除草机构的工作参数为机器前进速度为0.38m/s,除草盘转速162.75r/min,除草深度为43.9mm,此时除草率为80.5%、伤秧率为3.8%。 相似文献
88.
为探索板栗幼林抚育对生长的影响,通过板栗幼林中耕除草、间作与未间作对比试验。研究结果表明:中耕除草同龄的成活率以及树高、地径生长都比未中耕除草栗林有所增加,1次中耕除草效果差,中耕除草2~3次效果最好。间作薯类、豆类及谷类的板栗生长量比未间作的都有所增加,以间作薯类和豆类效果最明显。 相似文献
89.
Sarah Parry 《Journal of Crop Improvement》2018,32(1):124-139
Weed management in Romaine lettuce (Lactuca sativa L. var. longifolia) is an economic challenge for organic farmers. This study evaluated the effect of weed-free durations on crop yield and quality, weed densities and biomass, and weeding time in two growing seasons. Treatments included weedy entire-season; weed-free for 7 days after transplanting (DAT), 14 DAT, 21 DAT, 28 DAT, 35 DAT, 42 DAT; and weed-free entire season (49 DAT). Weeds were removed by hand-hoes and the time taken to weed each plot was recorded. Weed densities were recorded prior to each weeding and weed biomass was recorded at crop harvest. Total and marketable lettuce heads were recorded and crop quality was estimated. Weed interference up to 21 DAT resulted in approximately 45% total and 58% marketable yield loss. Weed control beyond this period did not result in significant (p < 0.05) increases in crop yield and quality. However, weed densities at the end of the season were 4- to 15-fold and weed biomass approximately 18-fold greater in plots kept weed-free only for 21 DAT compared with plots kept weed-free season-long. This suggested that weed seed-return may be a concern if late-season weeding is not conducted. To minimize weed seed-return, the plots would have to be kept weed-free for about 35 DAT. However, labor costs must be taken into consideration because the time required to hand-hoe was approximately 87 hr ha?1 person?1 greater in plots kept weed-free for 35 DAT compared with plots kept weed-free for 21 DAT. 相似文献
90.