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1.
在介绍江川灌区流域概况的基础上,提出了该灌区所面临的地下水灌溉水稻米质差、产量低、大米销路不好等问题的解决办法,即发展地表水灌溉水稻,通过引松花江水来解决灌溉水源;分别对地下水、地表水(松花江水)的水量和水质进行评价。结果表明,该灌区的地下水严重超采、水质中总铁量超标(超6mg/L),pH值偏碱,不适合用于农业灌溉;地表水(松花江水)除铁离子略高外,其余各项指标均满足灌溉要求,为该灌区引松花江水灌溉水稻提供了较为科学的依据。  相似文献   
2.
对尾叶桉苗木采用Pt菌剂(Pisolithus tinctorius)和水分胁迫处理,研究不同处理对该苗木生长及营养物质积累方面抗旱性的影响.结果表明:接种菌剂后水分胁迫条件比常规供水更利于苗高生长.无论常规供水还是水分胁迫条件下,接种菌剂10 g地径增长量都最大,高Pt菌剂施用量对地径增长量有一定的抑制作用.菌剂处理能提高苗木生长质量.常规条件下,菌剂5 g处理苗木质量最高;胁迫条件下,菌剂10 g处理苗木质量最高,而对总体抗旱性而言,菌剂15 g处理效果最好.  相似文献   
3.
Water is the most important environmental constrain determining plant growth and fruit yield of olive tree plantations. Although olive trees are resilient to water-limited conditions of Mediterranean-type agroecosystems, crop yields may respond positively to any additional water up to a limit. A field experiment on olive trees was carried out with the aim to present guidelines for efficient management of irrigation scheduling, based on the relationship between plant water status and optimum fruit yield. These relationships were monitored during 2 years by analysing the influence of deficit irrigation strategies on vegetative development and yield parameters on mature modern-trained olive trees of cvs. Frantoio and Leccino. Treatments were: a non-irrigated control (rainfed) and three treatments that received seasonal water amount equivalent to 33, 66 and 100% of ETC in the period August–September, from the beginning of pit hardening to early fruit veraison. Atmospheric evaporative demand and soil moisture conditions were regularly monitored. Seasonal dynamics of plant water relations varied among treatments, and responded to variations in tree water status, soil moisture conditions and atmospheric evaporative demand. All measurements of tree water status were highly correlated with one another. Differences in yield between treatments indicated that water availability might have affected fruit weight before flowering or during the early stages of fruit growth rather than later in summer season. Results concerning crop yield revealed that irrigation of olive trees from the beginning of pit hardening could be recommended, at least in the experimental conditions of this study and in view of differences between genotypes.  相似文献   
4.
研制了适合机关事业单位,学校和乡村等内部使用的机动灵活的微型多功能洒水车,介绍了该微型洒不库各系统的改装设计思路。  相似文献   
5.
【目的】 氮素营养和土壤水分是影响百合切花生长和品质的重要因素。本研究进行了不同氮肥配比和灌溉量对百合生长、切花期、切花观赏品质、瓶插寿命和瓶插期间叶片和花被片生理指标的影响,以期为百合切花生产的水氮管理提供科学依据。【方法】 以东方百合‘索邦’为材料,在施氮(N)量相同情况下,盆栽试验设5种氮素处理,即单施尿素,单施铵态氮肥,单施硝态氮肥,铵态氮:硝态氮(50%:50%)、尿素氮:硝态氮(50%:50%);2个灌水水平,即正常灌溉(苗期土壤含水量保持在60%~70%θf和现蕾期后70%~80%θff是田间持水量)和亏缺灌溉(苗期土壤含水量保持在50%~60%θf和现蕾期后60%~70%θf)。在百合停止生长后,测定了株高和茎粗、花朵数量、花径、瓶插寿命,开花第7天和第14天百合叶片和花被片中可溶性糖、可溶性蛋白和丙二醛含量。【结果】 铵态氮肥与硝态氮肥配施处理百合株高最高,花朵数量最多,切花瓶插寿命最长,开花第7天和第14天叶片和花被片中可溶性糖和可溶性蛋白含量较高,并缓解叶片和花被片中的丙二醛积累。与正常灌溉相比,亏缺灌溉对百合株高、花朵数量、花径、切花瓶插寿命以及开花后叶片和花被片中的丙二醛、可溶性糖和可溶性蛋含量的影响因不同氮肥处理而异。在两种灌水水平下,单施尿素、尿素和硝态氮肥配施以及铵态氮肥和硝态氮肥配施处理切花期分别为100 d、90 d和85~86 d。在正常灌溉条件下,单施铵态氮肥和单施硝态氮肥切花期差异不大,为85~86 d;而在亏缺灌溉条件下,单施硝态氮肥切花期为91 d,而单施铵态氮肥为87.5 d。【结论】 硝态氮肥和铵态氮肥配施可以提高百合株高和花朵数量,缩短百合切花期,延长切花瓶插寿命,从而提高百合切花品质。而亏缺灌溉对百合切花质量的影响因不同氮肥处理而异。  相似文献   
6.
To reveal the impact of soil disturbance and surface watering (SW) following soil disturbance on the pulse nitrous oxide (N2O) emissions, incubated experiments were conducted on disturbed soil with two watering regimes [surface watering only (SWO) and subsurface watering followed by surface watering (SUW+SW)]. Intensive soil disturbance led to pulses N2O emissions from SUW + SW soil (>8,693 μg N2O m?2 h?1 with a peak of 30,938 μg N2O m?2 h?1), although the water-filled pore space (WFPS) was substantially lower than the previously reported optimal soil moisture range (45–75% WFPS) for peak N2O emissions. N2O emissions from the disturbed soil after SW were much lower than those from SUW + SW soil, increased as the soil dried, and peaked when the WFPS fell within the optimal soil moisture range. These peaks were considerably less than those resulting from the intensive disturbance in SUW + SW soil. Thus, SW after intensive soil disturbance may be effective for mitigating of pulse N2O emissions caused by soil disturbance.  相似文献   
7.
本试验通过对接种黄萎病的地块进行不同浇水次数的处理来调查分析浇水次数对向日葵黄萎病发生程度及产量的影响.结果表明随着浇水次数的增多,向日葵黄萎病的发病严重度也随之增加,且向日葵的产量呈现降低的趋势.在接种的地块中浇水1次的病情病指由29.0递增到浇水3次51.5;产量则由浇水1次的4690.95kg/公顷降低至浇水3次的3815.55kg/公顷.  相似文献   
8.
以烤烟K326为材料,设叶面喷施和土壤浇灌2种方式分别对烤烟施加重金属Pb(20 mg/kg)、Hg(0.5 mg/kg)、Cd(25 mg/kg)、As(20 mg/kg)。采用盆栽试验在大田环境下进行,研究了重金属Pb、Hg、Cd、As在不同污染方式下对烤烟叶长、叶宽、茎围、株高、有效叶片数以及根体积生长发育的影响。结果显示,在Pb、Hg、Cd、As 4种重金属中,Pb和Hg的区别较大,土壤浇灌方式对烤烟生长发育的抑制作用比叶面喷施强;其次是As;Cd通过叶面喷施与土壤浇灌对烤烟生长影响不存在显著性差异。叶面喷施Pb对烟株有效叶片数和株高起着一定的促进作用,对根体积的影响最小。  相似文献   
9.
In this study, we developed a computer program for automatic prediction of watering time point by considering the environmental factors such as solar radiation, air temperature and relative humidity based on the multiple linear regression equation of leaf area and Penman Method. The experiments were carried out for a year in two watering experimental plots, one of which was controlled by pF value, and the other by the computer program. After comparing the results of the two plots, the following findings were obtained. In the computer program plot, the observed and predicted values of both leaf area and evapotranspiration indicated significant correlation at the 1% level, which suggested that the computer program had high prediction accuracy. In addition, no significant difference was observed between the two experimental plots with respects to the plant height, plant diameter, leaf area, leaf number, fresh weight, and dry weight, which demonstrated that the plants in the computer program plot had normal growth. On the other hand, although the number of flower buds and flowering shoots showed higher values at the end of certain cultivations in the computer program plot than those in pF value plot, we proposed that it was due to the effect of cumulative daily solar radiation in the greenhouse, rather than the watering. Thus, we have reached the conclusion that the computer program for automatic prediction of watering time point developed by this study has high applicability in miniature pot rose production.  相似文献   
10.
艾米乐是一种新型复合微生物制剂(EM菌肥),在马铃薯苗期叶面喷施和灌根处理,结果表明,艾米乐菌肥具有显著提高马铃薯产量和淀粉含量的功效,增产的主要原因是对马铃薯植株生长发育、各项生理指标、产量性状具有明显提高的效果。  相似文献   
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