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71.
菌渣部分替代草炭对樱桃番茄生长及养分吸收的影响研究   总被引:1,自引:1,他引:0  
为在大规模基质栽培中高效利用草炭资源,开展了菌渣部分替代草炭的栽培基质对樱桃番茄生长、产量及养分吸收的影响。利用充分腐熟的菌渣部分替代栽培基质中的草炭,以草炭和蛭石(2:1,V:V)为对照,进行田间试验,研究添加不同比例菌渣的栽培基质理化性状,及其对樱桃番茄生长、产量及养分吸收的影响。结果表明,不同比例菌渣替代草炭混配基质,其基质容重、孔隙度和pH均在理想基质要求范围之内,和对照相比,添加草炭后,基质碱解氮含量降低,钾元素含量升高,较高比例的菌渣复合基质导致樱桃番茄叶绿素含量降低,产量下降,而适宜比例的菌渣复合基质适宜樱桃番茄生长。T1(草炭:菇渣:蛭石:珍珠岩=3:3:3:1)处理适宜樱桃番茄生长,产量与对照差异不显著,果实品质好。适宜比例的腐熟菌渣替代草炭,既能保证樱桃番茄产量、品质,又能降低基质配制成本。  相似文献   
72.
为寻求蔬菜花卉秸秆简单、有效的利用方法,减少滇池流域农业面源污染。通过堆肥试验研究了蔬菜花卉秸秆接种微生物菌剂农冠和微元后,在翻堆和不翻堆2种处理方式下,高温堆肥过程中温度、全氮(T-N)、水溶性NH4 -N和水溶性NO3--N含量随时间的变化规律。结果表明:不翻堆的3个处理由于缺氧,发酵速率低,短期内不易腐熟。翻堆处理中,纯物料对照样品升温过程缓慢,高温分解阶段持续时间短, T-N损失大,堆肥品质差;添加微生物菌剂农冠后,与纯物料对照相比,提前3天进入高温分解阶段,高温分解持续时间延长4天,T-N含量损失比对照低10.9%,水溶性NH4 -N比对照降低24.7%,水溶性NO3--N则比对照增加14.0%;添加微生物菌剂微元后,与纯物料对照相比,提前5天进入高温分解阶段,高温分解持续时间延长6天,T-N含量损失比对照低24.1%,水溶性NH4 -N比对照降低29.3%,水溶性NO3--N则比对照增加24.2%。接种微生物菌剂可促进水溶性NH4 -N向水溶性NO3--N转化,降低堆肥容重,其中添加微元综合效果更理想。在翻堆条件下接种微生物菌剂微元可加快蔬菜花卉秸秆堆肥化进程,提高堆肥产品品质,且方法简单易行,适合在全流域进行广泛推广。  相似文献   
73.
Oil cultivars of Brassica napus L. were grown to compare the effects of composted municipal waste (CMW) and sheep manure (SM) to field soil (C0). To each soil group, one of three levels of urea nitrogen fertilizer (N) was added. SM grown plants had higher N than those grown in CMW with the Sarigol cultivar having a higher N content than the RGS cultivar. Field soil plants grown in control soil had lowest N levels. Organic amendments increased N content of both cultivars. SM grown plants produced more siliques, a higher seed yield, and greater 100 seed weight compared to those grown in CMW. Control soil plants had the lowest number of siliques, seed yield, and 100 seed weight. CMW-treated plants contained slightly more metals than SM plants. Field soil plants had the lowest metal levels. CMW and SM application had potential to improve the growth and chemical composition without adding urea.  相似文献   
74.
The distribution in soil and plant uptake of zinc (Zn) and lead (Pb) as influenced by pine bark-goat manure (PBG) compost additions were investigated from the soils artificially contaminated with Zn or Pb ions using maize (Zea mays L.) as a test crop. Soils were amended with four rates of pine bark-goat manure compost (0, 50, 100, and 200 tons ha?1) and four rates (0, 300, 600 and 1200 mg kg?1) of Zn or Pb. Maize was planted and grown for 42 days. At harvest, plants samples were analyzed for Zn and Pb concentration. Soils samples were analyzed for pH, extractable and diethylene triamine pentaacetic acid (DTPA) extractable Zn and Pb. Extractable Zn and Pb was lower in PBG compost amended soils than in unamended soils and steadily declined with increasing amount of compost applied. The extractable fraction for Zn dropped by 62.2, 65.0 and 44.6% for 300, 600 and 1200 mg Zn kg?1, respectively when 200 t ha?1 of PBG compost was applied. Metal uptake by maize plants were directly related to the rate of applied heavy metal ions with greater concentrations of metals ions found where metal ions were added to non-amended soils.  相似文献   
75.
Field experiments were carried out during rainy (kharif) and winter (rabi) seasons (June–April) of 2008–2010 at Indian Agricultural Research Institute (IARI), New Delhi, to study the productivity, nutrients uptake, iron (Fe) use-efficiency and economics of aerobic rice-wheat cropping system as influenced by mulching and Fe nutrition. The highest yield attributes, grain and straw yields (5.41 tonnes ha?1 and 6.56 tonnes ha?1, respectively) and nutrient uptake in rice was recorded with transplanted and puddled rice (TPR) followed by aerobic rice with Sesbania aculeata mulch. However, residual effect of aerobic rice with wheat straw mulch was more pronounced on yield attributes, grain and straw yields (4.20 and 6.70 tonnes ha?1, respectively) and nutrient uptake in succeeding wheat and remained at par with aerobic rice with Sesbania mulch. Application of iron sulfate (FeSO4) at 50 kg ha?1 + 2 foliar sprays of 2% FeSO4 was found to be the best in terms of all the yield attributes, grain and straw yield (5.09 and 6.17 tonnes ha?1, respectively) and nutrient uptake and remained at par with 3 foliar sprays of 2% FeSO4. Although residual effect of iron application failed to increase the yield attributes, yield and nutrient uptake nitrogen, phosphorus and potassium (N, P, K) except Fe. The highest system productivity, nutrient uptake, gross returns, net returns, B: C ratio and lowest cost of cultivation were recorded with aerobic rice with wheat straw and Sesbania aculeata mulch. Application of FeSO4 at 50 kg ha?1 + two foliar sprays of 2% FeSO4 was found better in respect of system productivity, nutrient uptake, gross returns, net returns, B:C ratio and cost of cultivation in aerobic rice-wheat cropping system. The Fe use efficiency values viz. partial factor productivity (kg grain kg?1 Fe), agronomic efficiency (kg grain increased kg?1 Fe applied), agrophysiological efficiency (kg grain kg?1 Fe uptake), physiological efficiency (kg biomass kg?1 Fe uptake), apparent recovery (%) utilization efficiency and harvest index (%) of applied Fe were significantly affected due to methods of rice production and various Fe nutrition treatments in aerobic rice and aerobic rice-wheat cropping system.  相似文献   
76.
A field experiment was carried out in Southern Italy from 2007 to 2010 adopting a two-year rotation of tomato and maize. In this paper, the results of maize cultivation were reported, with the aim to investigate the effects of different water qualities and fertilizers on yield and soil properties. The following treatments were compared: mineral nitrogen (N) fertilizer and irrigation with fresh water (FWF); mineral N fertilizer and irrigation with saline water (SWF); Municipal Solid Waste (MSW) compost and irrigation with fresh water (FWC); MSW compost and irrigation with saline water (SWC). These treatments were compared with an unfertilized control and irrigation with fresh-water (FW0) and an unfertilized control and irrigation with saline water (SW0). At harvest, yield, grain moisture content, dry matter, grain protein, starch, fat content and soil characteristics were determined. The treatments with compost increased the average grain yield of the 11% compared to mineral fertilizer treatments. Furthermore, the grain yield in SWC increased of the 19% respect to average of SWF and SW0, indicating that MSW compost applied as amendment mitigated the adversely effects of saline water. Compost application significantly increased the Total Organic Carbon (TOC). In particular, the FWC and SWC treatments showed an average increase of the 25% compared to the mean TOC value of FWF and SWF. Moreover, at the end of the experiment, electrical conductivity decreased in SWC treatment respect to the SWF (?21%).  相似文献   
77.
脲酶抑制剂NBPT对鸡粪好氧堆肥的保氮效果   总被引:2,自引:0,他引:2       下载免费PDF全文
利用堆肥反应器, 以鸡粪和蘑菇渣为原料进行好氧堆肥, 在堆肥中添加不同浓度的脲酶抑制剂NBPT, 研究其对堆肥氮素转化的影响及保氮效果。结果表明: 添加不同浓度的脲酶抑制剂NBPT对堆肥进程中温度无显著影响, 在堆肥的高温阶段可有效控制堆料pH的升高, 在堆肥高温前期的0~10 d可有效降低堆肥的脲酶活性, 在堆肥中后期10~25 d明显提高全氮含量。堆肥25 d后, 添加0.04 mL·kg-1、0.08 mL·kg-1、0.16 mL·kg-1脲酶抑制剂NBPT分别比CK减少氮素损失6.61%、4.89%和13.51%。堆肥过程中, 堆料铵态氮含量呈升-降-升-降的双峰趋势, 且大部分时间CK处理的铵态氮含量高于添加脲酶抑制剂NBPT处理, 且CK处理铵态氮的两次升高速度均高于添加脲酶抑制剂NBPT处理。在堆肥的升温和高温期硝态氮含量不稳定, 但堆肥结束时, 各添加脲酶抑制剂NBPT处理的硝态氮含量显著高于CK处理。本试验结果表明, 在堆肥过程中添加脲酶抑制剂NBPT可延缓鸡粪中的尿素态氮向铵态氮的转化, 增加堆肥成品中的硝态氮含量。在畜禽粪好氧堆肥中加入脲酶抑制NBPT可起到一定的保氮作用。  相似文献   
78.
The objective of this study was to determine the effect of ensiling different ratios of whole crop oat to lucerne on fermentation quality, aerobic stability and in vitro digestibility of silage on the Tibetan plateau. Four experimental treatments were produced varying in the ratio of forages on a fresh matter (FM) basis: 1) 100% oat (control, dry matter (DM) content: 317 g/kg), 2) 90% oat + 10% lucerne (OL10, DM content: 316 g/kg), 3) 80% oat+ 20% lucerne (OL20, DM content: 317 g/kg) and 4) 70% oat+ 30% lucerne (OL30, DM content: 318 g/kg). All treatments were packed into laboratory‐scale silos and ensiled for 60 days and then subjected to an aerobic stability test for 15 days. Further, the four experimental treatments were incubated in vitro with buffered rumen fluid to study the nutrient digestibility. All silages were well preserved with low pH and NH3‐N contents, and high lactic acid contents and V‐scores (evaluation of silage quality). Increasing the lucerne proportion increased (p < 0.05) crude protein (CP) content of silage, whereas neutral (NDF) and acid (ADF) detergent fibre contents were not affected. Under aerobic conditions, the control silage showed higher (p < 0.05) yeast counts (>10cfu/g FM) followed by OL10 silage, and OL10 silage improved aerobic stability for 74 h. OL20 and OL30 silages showed fewer (p < 0.05) yeasts (<105 cfu/g FM) and markedly (p < 0.05) improved the aerobic stability (>360 h). After 48‐h incubation, OL30 silage increased (p < 0.05) in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) compared with the control silage. These results suggest that replacing oat with lucerne had no unfavourable effects on fermentation quality of silage, but improved CP content, aerobic stability IVDMD and IVNDFD. OL30 silage was the best among the three mixed silages.  相似文献   
79.
腐熟堆肥回流对中药渣好氧堆肥进程及堆肥品质的影响   总被引:1,自引:1,他引:0  
为明确腐熟堆肥回用对中药渣好氧堆肥腐熟效率及堆肥产品品质的影响,探讨堆肥过程中养分转化规律及腐殖质形态、组分、品质的动态变化,在工厂化条件下比较了中药渣自然堆肥与添加腐熟中药渣堆肥(质量分数10%)堆肥过程中碳氮磷硫和腐植酸类物质的动态变化特征。结果表明,添加腐熟堆肥比自然堆肥提前20 d进入高温期,且高温期平均温度高于自然堆肥5℃左右。较之自然堆肥,添加腐熟堆肥可以强化有机物降解,堆肥产品的总碳含量与C/N显著下降(P0.05),而全氮、全磷、全钾和全硫分别增加17.5%、17.8%、14.7%和9.4%;两个处理堆肥前后总腐植酸、游离腐植酸和水溶性腐植酸含量变化不大,但添加腐熟堆肥处理可提高腐植酸的活性,增加游离腐植酸(7.8%)及水溶性腐植酸含量(30.1%);堆肥过程胡敏酸组分不断增加,富里酸组分逐渐降低,添加腐熟堆肥处理可强化堆肥腐殖化进程,增加胡敏酸组分(15.2%),胡富比显著升高,堆肥产品的分子量、缩合度及芳构化程度提高。研究表明,腐熟堆肥回流能够显著促进中药渣堆肥腐熟效率,提高堆肥产品品质。  相似文献   
80.
采用高通量测序技术,研究牛粪堆肥过程中不同时期与不同深度的nosZ型反硝化细菌群落组成的动态变化与多样性,并通过冗余分析(Redundancy analysis, RDA)和Spearman相关性分析,揭示了堆肥过程中nosZ型反硝化细菌与理化指标之间的相关关系。结果表明,堆肥不同时期nosZ型反硝化细菌群落结构差异显著,反硝化细菌群落多样性和丰富度均呈先降低后升高的趋势,在堆肥降温期不同深度的反硝化细菌群落结构和多样性指数差异显著。此外,理化因素显著影响堆肥反硝化菌群的群落结构与多样性,螯台球菌属(Chelatococcus)与温度呈极显著正相关(P0.01),Polymorphum与硝态氮呈极显著正相关(P0.01),生根瘤菌属(Mesorhizobium)与含水率和C/N呈极显著负相关(P0.01)。反硝化细菌的多样性与温度、pH、氨态氮呈极显著负相关(P0.01),与硝态氮呈极显著正相关(P0.01)。反硝化细菌的丰富度与温度呈极显著负相关(P0.01)。综上所述,堆肥时间和深度均为影响nosZ型反硝化细菌群落结构的重要因素,且该菌群群落结构变化受理化因子的显著影响。  相似文献   
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