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931.
以麻竹笋用林高效栽培为目标,可持续经营为原则,总结了竹林林分结构调控、土壤管理、散生状培育、地理种源和无性系选优等操作简便、应用效果好的系列实用技术,分析了目前麻竹林立地生产力退化、产品产量和质量下降等的主要原由,提出了无害化、品种化和散生状培育的经营方向。 相似文献
932.
雷竹引种栽培时,移栽母竹应用3种方法进行处理.其一用黄泥浆溶液进行处理,二是吲哚丁酸溶液处理,三是ABT 3号生根粉溶液处理.栽培后,对母竹3种处理的试验,苗木生根长鞭、成活率、出笋率、生长量进行观察分析.结果表明,用ABT 3号生根粉溶液浸泡的母竹栽培,比吲哚丁酸和黄泥浆溶液处理的生根长鞭分别提高29%、45%,成活率分别提高4%和7%,出笋率分别提高52%、64%. 相似文献
933.
934.
1992年在云南省元江县 4个引种点的种植试验结果表明 :番荔枝在元江海拔 4 0 0~ 92 1m ,年均温 2 1~2 4℃的干热河谷地区生长良好 ,种后 2~ 3年开始结果 ,每hm2 产量达 2 5 5 4kg ;6年生幼树每hm2 产果 14 4 5 8kg,产值 4 86 30元。番荔枝对土壤的适应性较强 ,但以砂壤土种植为宜 ,可获高产。番荔枝间种芒果模式 ,是提高幼林果园经济效益的一种有效经营方式。另对番荔枝的育苗、种植技术、水肥管理、整形修剪、病虫害防治等作了系统介绍 相似文献
935.
叙述了葡萄避雨栽培简易大棚的结构和双十字V形整枝技术;采用石灰氮处理并在1月中、下旬的覆膜技术,打破葡萄的休眠期,促使提早萌芽结果,同时通过棚内光照、温度、湿度的调节,结合施肥,整形修剪等配套技术,达到葡萄的优质、稳产、高产。 相似文献
936.
Traditional fallow systems of Latin America have not been extensively studied from either a socioeconomic or biophysical viewpoint. Only in the past decade have some of these systems — modified shifting cultivation in the Amazon, the bracatinga (Mimosa scabrella) fallow of southeastern Brazil, the babassu (Attalea spp.) system of the Amazon margins, and short bush fallows mostly for Phaseolus bean (the so-called frijol tapado) — received any attention. Over the past century, traditional cultivators have adopted several legumes such as Mucuna spp., Lathyrus nigrivalis, Canavalia spp., and Senna guatemalensis as green manures or managed fallows in food crop production systems, which have recently been the object of studies by social and biological scientists. Longer, monospecific fallows involving woody legumes have been studied to varying degrees. The legumes include Senna guatemalensis, Mimosa tenuiflora, and Gliricidia sepium. Systems in which crop production is alternated with animal grazing of secondary vegetation include the caatinga of Northeast Brazil, the espinales of Chile, the matorrales of northern Mexico, and the chaco of Argentina, Paraguay, and Bolivia. A classification is proposed depending on the nature of the species (woody or nonwoody) and their composition (mono- or multispecies) and land management (burned or not). Much work is still needed in more complete characterization, determination of economic importance and potential, understanding the relationships among components, studies of nutrient cycling, and verification of the effects of shorter fallow periods of these systems.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
937.
对12年生杜仲进行人工供水处理,研究土壤水分对皮叶两用杜仲林萌条生长规律的影响.结果表明:不同水平的供水对新枝生长均有促进作用,6~9月份,Ⅰ、Ⅱ、Ⅲ、Ⅳ级供水处理的新枝枝长生长量分别较对照增加30.2%、37.1%、77.9%、56.2%,新枝直径生长量分别较对照增加22.4%、53.7%、117.9%、83.6%;Ⅲ级供水最有利于萌条的生长,二次分枝数最多(43个/株),平均枝条长度最长(27.3 cm),单株叶片数和叶干质量分别为162个.株-1和16.5 g.株-1;杜仲供水多时,水分并不能被根部全部吸收,水分利用效率降低;5~9月份,秦岭南坡杜仲适宜的灌水量为1 050 m3.hm-2. 相似文献
938.
Managed short-duration fallows may have the potential to replace longer fallows in regions where population density no longer
permits slow natural fallow successions. The purpose of fallows is not only to improve subsequent crop performance but also
to restore soil fertility and organic matter content for the long term. We therefore evaluated the soil organic matter and
nutrient flows and fractions in a short fallow experiment managed in the western Kenya highlands, and also compared the experimental
area with a 9–12-yr-oldadjacent natural bush fallow. The factorial agroforestry field experiment with four land-use and two
P fertilizer treatments on a Kandiudalfic Eutrudox showed that 31-wk managed fallows with Tithonia diversifolia(Hemsley) A. Gray and Crotalaria grahamiana Wight &Arn. improved soil fertility and organic matter content above those of a natural weed fallow and continuous maize
(Zea mays L.). Post-fallow maize yields were also improved, although cumulative three-season increases in yield were small (0–1.2 Mg
ha−1) when the yield foregone during the fallow season was accounted for. Improvements in yield and soil quality could be traced
to quantity or quality of biomass recycled by the managed fallows. The non-woody recycled biomass produced by the continuous
maize, weed fallow, and tithonia treatments was near 2Mg ha−1, whereas crotalaria produced three times more recyclable biomass and associated N and P. Increases in topsoil N due to the
fallows may have been attributable in part to deep acquisition and recycling of N by the fallows. Particulate macro-organic
matter produced by the fallows contained sufficient N(30–50 kg ha−1) to contribute substantially to maize production. Organic Paccumulation (29 kg ha−1) similarly may play a significant role in crop nutrition upon subsequent mineralization. The effect of the P fertilizer application
on soil properties and maize yield was constant for all land-use systems (i.e., no land-use system × P fertilizer interactions
occurred). There was an indication that tithonia may have stimulated infestation of Striga hermonthica (Del.) Benth., and care must be taken to evaluate the full effects of managed fallows over several seasons.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
939.
940.
香菇等食用菌在我国具有近千年的栽培历史,是山区经济发展的重要产业,食用菌原料林的培育对于以阔叶权赤原食用菌产业持续发展意义重大。本文重点对食用菌原料林树种的优选、人促更新定向培育、主要原料林树种的丰产栽培以及其采种基地建设等进行述评。根据食用菌原料林培育研究现状和存在问题,提出进一步发展的技术对策和今后的研究重点,包括主要原料树树的种的良种选育和扩繁技术、育苗技术、松杉林冠下造林技术和多种食用菌原料林树种混植技术、二代食用菌原料林的萌芽更新技术等。 相似文献