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171.
Recycling of rice straw to improve wheat yield and soil fertility and reduce atmospheric pollution 总被引:3,自引:0,他引:3
Dr. Himanshu Pathak Ph.D. Ramandeep Singh M.Sc. Dr. Arti Bhatia Ph.D. Dr. Niveta Jain Ph.D. 《Paddy and Water Environment》2006,4(2):111-117
Burning of rice straw is a common practice in northwest India, where rice–wheat cropping system is extensively followed. The practice results in loss of nutrients, atmospheric pollution and emission of greenhouse gases. A field experiment was conducted at Indian Agricultural Research Institute, New Delhi, India during the rabi season (November to April) of 2002–2003 to evaluate the efficacy of the various modes of rice straw recycling in soil in improving yield and soil fertility and reducing not only carbon dioxide emission but also nitrous oxide (N2O) emission. The treatment with no rice straw incorporation and application of recommended doses of fertilizer (120, 26 and 50 kg N, P and K ha−1, respectively), gave the highest yield of wheat. Treatments with the incorporation of rice straw at 5 Mg ha−1 with additional amount of inorganic N (60 kg N ha−1) or inoculation of microbial culture had similar grain yields to that of the treatment with no straw incorporation. The lowest yield was recorded in the plots where rice straw was incorporated in soil without additional inorganic N and with manure application. All the treatments with rice straw incorporation had larger soil organic C despite the effect on the mineralisation of soil organic matter. Emission of N2O was more when additional N was added with rice straw and secondary when straw was added to the soil because of higher microbial activity. The study showed that burning of rice straw could be avoided without affecting yield of wheat crop by incorporating rice straw in soil with an additional dose of inorganic N or microbial inoculation. However, the reduction of N2O emission due to avoiding burning is in part counterbalanced by an increase in emission during the subsequent wheat cultivation. 相似文献
172.
为探讨黑土有机碳的长期变化规律及DNDC模型在土壤有机碳预测方面的适用性,本文利用吉林省公主岭地区黑土不同施肥措施下的长期定位试验数据,选取不施肥(CK)、单施化肥(NPK)、配施有机肥(NPKM)和增施有机肥(M2+NPK)4个处理进行土壤有机碳分析,并将数据用作DNDC模型验证。验证结果表明:各处理DNDC验证中RMSE值均小于10%(分别为5.09%、6.11%、9.38%、8.36%),说明模拟值与观测值一致性良好,模型可用于该地区土壤有机碳模拟。选取了化肥施用、有机肥施用、秸秆还田比率、温度及降水5个因子进行模型的敏感性分析,结果表明:有机肥的施用对土壤有机碳含量的影响最显著,且这种影响具有持久性。最后模拟了4种施肥情境下未来(至2100年)的土壤有机碳变化情况。结果表明:对照不施肥处理(CK)土壤有机碳含量略有下降,至2100年土壤有机碳含量为11.55 g·kg-1,较试验前土壤初始有机碳(13.2 g·kg-1)下降约12.5%。单施化肥处理(NPK)土壤有机碳含量较为稳定,并未出现土壤有机碳含量下降。配施有机肥(NPKM)和增施有机肥(M2+NPK)处理土壤有机碳含量增加明显,至2100年土壤有机碳含量为24.4 g·kg-1和27.6 g·kg-1,分别较初始有机碳含量上升84.8%和109.1%。 相似文献
173.
A new methodology based on (1) national data concerning livestock and rearing practices and (2) a mass-flow approach was developed to quantify ammonia (NH3), methane (CH4) and nitrous oxide (N2O) emissions resulting from manure management in France. A literature review was performed to determine emission factors for each animal type and each management stage. A Microsoft Access® database containing these emission factors, the census data and manure compositions was then developed, allowing the calculation of gaseous emissions by the mass-flow approach. From this database, a national gas emissions inventory resulting from manure management was drawn up for the year 2003. Total NH3 emissions were estimated at 382 kt N, mainly arising from cattle (72%). Greenhouse gas emissions were estimated at 14.0 Tg CO2-eq. for N2O and 10.2 Tg CO2-eq. for CH4. Most of the N2O emissions occurred after the deposition of manure on soil during cattle grazing, while the CH4 was mainly produced during the period where cattle manure remained in livestock buildings and in outside storage facilities. Moreover, an evaluation of the uncertainty was performed considering the standard deviation obtained for the emission factors. 相似文献
174.
研究粪肥堆腐过程中尿囊素 ( All)含量变化表明 :4种粪肥的变化趋势相同即呈抛物线型 ,但变化的速度不同。加入含氮添加物能显著提高粪肥中 All的含量 ,并在堆腐后期能减缓All的下降速率。研究还表明 ,蛋白质和核酸的变化对 All的含量也有影响 ,通径分析结果 ,蛋白质对 All的累积直接贡献大 ,核酸的直接作用较小 ,两者的间接作用都小 相似文献
175.
176.
长期培肥黑土脱氢酶活性动态变化及其影响因素 总被引:6,自引:0,他引:6
对东北典型黑土区长期不同培肥黑土脱氢酶活性在作物生长季的动态变化进行研究。结果表明,施用有机肥,生长季黑土总体脱氢酶活性显著高于施用化肥和不施肥,其生长季脱氢酶活性保护容量在5.5 mg TPF/kg土.h以上,黑土总体脱氢酶活性施用高量有机肥>低量有机肥>不施肥>化肥,季节性变化波动性大。长期施用高量有机肥脱氢酶活性最大峰值出现在拔节期,施用低量有机肥、化肥和不施肥最大峰值出现在完熟期;长期施用不同数量和种类肥料所引起的黑土总体脱氢酶活性差异并未因玉米生长影响而改变,说明长期施用高量有机肥黑土微生物氧化活性能力增强,土壤自身调解和维持肥力能力增强。黑土脱氢酶活性的动态变化与绝大多数土壤生物、理化特性指标的动态变化没有显著的相关性;总体脱氢酶活性与多数土壤生物、理化特性因子、植物全磷、钾含量有极显著和显著正相关关系。 相似文献
177.
施用有机肥(牛猪厩肥、鸡粪及作物秸秆、油菜绿肥)对土壤K素供应能力及其特点试验结果表明,肥料与土壤共同培养30d左右向速效钾转化达到平衡,向缓效钾转化至70d趋于平缓。肥料中有效钾素在土壤中有效转化率约为50%~87%,其中以缓效钾为主,约占50%~80%。不同供K源中麦秸对土壤K素供应能力高于K化肥,3种厩肥低于K化肥,不同土壤类型和土壤环境因素对有机肥供K能力有不同影响。 相似文献
178.
Temporal behaviour of microbial biomass C, N and respiration was measured under barley crops in two experiments on successive
years in a recently converted organic production system in Scotland. Soils were fertilised with farmyard manure or poultry
manure. Control soils received no manure at the start of the growing season. The effects of plants was also investigated by
maintaining fallow subplots. C-flush values approximately doubled over the growing season in both years of the trial, showing
a decline to pre-sowing values between the two seasons. This occurred in all soils, whether manured or not, or planted or
fallow. Manure tended to increase the C-flush in the 2nd year only. N-flush in the 2nd year showed no increase in planted
control plots but did increase in fallow soils. Manures significantly increased the N-flush. Respiration rates were stimulated
by the presence of plants. Respiration rates were measured from soils taken from the field at post-sowing, mid-season and
post-harvest occasions and incubated under constant conditions for up to 1 year. Here there was evidence that the effects
of sampling and adjusting the moisture status could be as great upon microbial activity as the addition of the manures. C-flush
also showed a consistent and persistent increase in these incubated soils. This suggests that the fundamental C-supplying
characteristics of these soils was such that the biomass was moving towards a new equilibrium value fuelled by the relatively
recent introduction of the organic farming regime.
Received: 27 February 1996 相似文献
179.
R. L. Haney F. M. Hons M. A. Sanderson A. J. Franzluebbers 《Biology and Fertility of Soils》2001,33(2):100-104
A routine soil testing procedure for soil N mineralization is needed that is rapid and precise. Not accounting for N mineralization
can result in the over-application of N, especially in soils with a history of manure application. Our objectives were to
compare results from a recently proposed rapid laboratory procedure with: (1) long-term N mineralization under standard laboratory
conditions, and (2) actual forage N uptake from soil receiving dairy cattle (Bos taurus) manure in a 2-year field study. The rapid procedure is based on the quantity of CO2-C evolved during 24 h under optimum laboratory conditions following the rewetting of dried soil. Dairy cattle manure was
surface applied beginning in 1992 at annual rates of 0, 112, 224, or 448 kg N ha–1 to field plots on a Windthorst fine sandy loam soil (fine, mixed, thermic Udic Paleustalf) near Stephenville, Texas (32°N,
98°W). Results of the one-day CO2 procedure were highly correlated with soil N mineralized from samples collected in March of 1995 (P=0.004) and 1996 (P<0.001) and with forage N uptake (P<0.001) both years of the study. Residual inorganic N in the same soil samples was poorly correlated with soil N mineralization
and forage N uptake.
Received: 23 February 2000 相似文献
180.
Origin and fate of soil lipids in a Phaeozem under rye and maize monoculture in Central Germany 总被引:1,自引:0,他引:1
Although soil lipids are an important class of soil organic substances, which is involved in numerous soil processes, their
origin and fate in soils is insufficiently known. Therefore, this study aimed at investigating the free lipid fraction in
crop residues and farmyard manure (FYM), and soils which received these materials for long time. We sampled rye and maize
stubble and roots, FYM, and Ap horizon soils from the ‘Unfertilized’ and ‘FYM’ plots of ‘Eternal Rye Cultivation’ experiment
at Halle, Saxony-Anhalt, Germany. Free lipids were extracted by dichloromethane/acetone and analyzed by gas chromatography/mass
spectrometry. Aliphatics were most abundant in all extracts, accounting for 61 to 77% of the total extractable lipids. By
comparing the lipid composition of the added organic materials with that of the corresponding treated soil, the long-chain
members of n-alkanols, n-alkanes, α,ω-alkanedioic acids, and unsaturated alkanoic acids from C16 to C19 did not disappear in soil whereas ω-hydroxyalkanoic acids and long-chain branched alkanoic acids were not extracted from
soil probably because they were bound to nonextractable forms. It is suggested that the methodological approach can give information
on decomposition and retention of free extractable lipids in soil. More information is needed to trace the fate of all lipids
in the plant–soil system by the determination of bound molecules, which are nonextractable by organic solvents. 相似文献