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591.
Frantiek Kühn Harald Ohle und Klaus Pistrick 《Genetic Resources and Crop Evolution》1984,32(4):153-196
Zusammenfassung Das während der Reise in ein Gebirgsgebiet der westlichen Slowakei 1981 (vgl.Kühn et al. 1982) gesammelte Kulturpflanzenmaterial wird botanisch charakterisiert. Es handelt sich überwiegend um Landsorten, alte Sortentypen und Kultursippen von oft sehr hoher Variabilität, deren Anbau meist in raschem Rückgang begriffen ist. Charakteristische indigene Formen konnten u. a. noch beiTriticum aestivum, Avena sativa, Papaver somniferum, Pisum sativum undPhaseolus vulgaris nachgewiesen werden. Bemerkenswert ist das Vorkommen ausgesprochener Reliktkulturen (z. B.Triticum dicoccon, Secale cereale var.multicaule, Panicum miliaceum, Cicer arietinum, Lathyrus sativus undFagopyrum esculentum). Die Gebirgsregion gehört zum Erhaltungsgebiet autochthoner Kulturpflanzen-Sippen in den Westkarpaten. Das rasche Fortschreiten der Generosion läßt eine baldige Fortführung der Sammeltätigkeit notwendig erscheinen.
Catalogue of indigenous taxa of cultivated plants collected 1981 in the SSR
Summary The material of cultivated plants collected during a mission to western Slovakia in 1981 (cf.Kühn et al. 1982) has been characterized botanically. It is represented mainly by land-races and old varieties which are often rather variable; their cultivation is mostly decreasing rapidly. Typical indigenous types could be discovered e.g. forTriticum aestivum, Avena sativa, Papaver somniferum, Pisum sativum andPhaseolus vulgaris. Remarkable is the occurrence if indigenous relic crops (e.g.Triticum dicoccon, Secale cereale var.multicaule, Panicum miliaceum, Cicer arietinum, Lathyrus sativus andFagopyrum esculentum). The mountainous region belongs to the Western Carpathian refugial area of autochthonous taxa of cultivated plants. Because of rapidly acting genetic erosion a continuation of the collecting work seems to be necessary now.
, 1981 .
, 1981 . (. ., 1982). , , ; . , ., , , , . (.:Triticum dicoccon, Secale cereale var.multicaule, Panicum miliaceum, Cicer arietinum, Lathyrus sativus, Fagopyrum esculentum). . ¶rt; 7qo .相似文献
592.
The distribution and natural abundance isotopic (δ15N) content of whole tissue and individual amino acids in plants in a temperate grassland were determined using ion chromatography (IC), continuous flow‐isotope ratio mass spectrometry (CF‐IRMS), and gas chromatography‐combustion‐isotope ratio mass spectrometry (GC‐C‐IRMS). The results showed that the selected plants (Lolium perenne, Juncus effusus, and Brachythecium rutabulum) differed in their amino acid content and distribution from the parent grassland soil. Bulk and individual amino acid δ15N isotope signatures were different between the plants, which concurred with their functional strategy in relation to the relative acquisition of available N sources. The individual amino acid δ15N values of histidine and phenylalanine could be used to differentiate between the three plant species. 相似文献
593.
594.
Effect of the heavy metals chromium, nickel, copper, zinc, cadmium, mercury and lead on uptake and translocation of K and P by young barley plants The uptake of potassium and phosphate into the roots and shoots of 7 days old barley plants from double-labelled (42K, 32P) nutrient solutions containing chromium, nickel, copper, zinc, cadmium, mercury or lead (10?6 - 10?4 moles/1) was measured in a constant environment after 5 hours, in order to compare early stages of toxicity. K and P uptake and translocation were inhibited by the 7 heavy metals to a different extent; K was more affected than P, and translocation of both nutrients into the shoots was more inhibited than uptake into the roots. Plants showed no visible injuries. Mercury had by far the greatest effect, zinc was almost ineffective: K uptake e.g. was reduced to 21% of the control by 10?4 moles Hg/l, but only to 97% by the same amount of Zn, and P translocation was reduced to 8% by Hg, but was not affected by Zn. The least significant effect of Hg was detectable at a concentration of 4.10?7 moles Hg/l ( = 0,08 ppm) in the nutrient solution, the effect of Zn only above 10?4 moles Zn/l ( = 6,5 ppm). Arranging the tested heavy metals according to their effects leads to the sequence Hg > Pb > Cu > Cd > Cr > Ni > Zn which corresponds – apart from two deviations – to the electrochemical series of the elements. 相似文献
595.
3,4-Dimethylpyrazole phosphate (DMPP) – a new nitrification inhibitor for agriculture and horticulture 总被引:16,自引:0,他引:16
Wolfram Zerulla Thomas Barth Jürgen Dressel Klaus Erhardt Klaus Horchler von Locquenghien Gregor Pasda Matthias Rädle Alexander Wissemeier 《Biology and Fertility of Soils》2001,34(2):79-84
3,4-Dimethylpyrazole phosphate (DMPP) is a new nitrification inhibitor with highly favourable properties. It has undergone thorough toxicology and ecotoxicology tests and application-technology experiments, and has been shown to have several distinct advantages compared to the currently used nitrification inhibitors. Application rates of 0.5-1.5 kg ha-1 are sufficient to achieve optimal nitrification inhibition. DMPP can significantly reduce NO3- leaching, without being liable to leaching itself. DMPP may reduce N2O emission, apparently without a negative effect on CH4 oxidation of the soil. The use of DMPP-containing fertilizers can improve yield. This offers the possibility of saving mineral fertilizer N, reducing the number of N-application rounds, and obtaining higher crop yields with current fertilizer-N rates. 相似文献
596.
Dr. Jürgen Schultze-Motel Dr. Reinhard Fritsch Dr. Karl Hammer Dr. Peter Hanelt Dr. Joachim Kruse Dr. Helga I. Maass Dr. Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1981,29(2):465-483
Summary Important papers on taxonomy and evolution of cultivated plants published in 1979 and 1980 were put together and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1979/1980
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1979 und 1980 wurden zusammengestellt und kurz kommentiert.
: 1979–1980
, 1979–1980 . .相似文献
597.
Providing the Parameters of Unsaturated Soil Hydraulic Functions on the Basis of Soil Texture, Bulk Density and Type of Horizon The hydraulic conductivity function can be described by the van Genuchten equation, whereby its parameters are estimated from typical water retention data of soil types and textural classes. The value of saturated hydraulic conductivity can be derived from tables (e.g. Kartieranleitung, 1982) in case measured data are lacking. Especially in well structured or sandy soils saturated conductivity may differ by 1…2 orders of magnitude. This will lead to a shift of the conductivity function. But nevertheless for the first approximation of fluxes in soils such parameters can be used. Thus, soil dependent values of groundwater recharge and pollution can be roughly quantified. 相似文献
598.
599.
Temperature sensitivity of soil organic matter decomposition varies with biochar application and soil type 总被引:1,自引:0,他引:1
Tatiana F. RITTL Luiza CANISARES Edvaldo SAGRILO Klaus BUTTERBACH-BAHL Michael DANNENMANN Carlos E. P. CERRI 《土壤圈》2020,30(3):336-342
Biochar application has the potential to improve soil fertility and increase soil carbon stock, especially in tropical regions. Information on the temperature sensitivity of carbon dioxide(CO_2) evolution from biochar-amended soils at very high temperatures, as observed for tropical surface soils, is limited but urgently needed for the development of region-specific biochar management targeted to optimize biochar effects on soil functions. Here, we investigated the temperature sensitivity of soil respiration to the addition of different rates of Miscanthus biochar(0, 6.25, 12.5, and 25 Mg ha~(-1)) in two types of soils with contrasting textures. Biochar-amended soil treatments and their controls were incubated at constant temperatures of 20, 30, and 40℃. Overall, our results show that: i) considering data from all treatments and temperatures, the addition of biochar decreased soil CO_2 emissions when compared to untreated soils;ii) CO_2 emissions from biochar-amended soils had a higher temperature sensitivity than those from biochar-free soils; iii) the temperature sensitivity of soil respiration in sandy soils was higher than that in clay soils; and iv) for clay soils, relative increases in soil CO_2 emissions from biochar-amended soils were higher when the temperature increased from 30 to 40℃, while for sandy soils, the highest temperature responses of soil respiration were observed when increasing the temperature from 20 to 30℃. Together, these findings suggest a significantly reduced potential to increase soil organic carbon stocks when Miscanthus biochar is applied to tropical soils at high surface temperatures, which could be counteracted by the soil-and weather-specific timing of biochar application. 相似文献
600.
Wegmann J Krucker M Bachmann S Fischer G Zeeb D Lienau A Glaser T Runge F Lüddecke E Albert K 《Journal of agricultural and food chemistry》2002,50(26):7510-7514
The core-shell structure of lycopene micronizates can be verified by employing a combination of solid-state and suspended-state NMR spectroscopy. The type of molecular aggregation of carotenoid nanoparticles can be clearly determined from their characteristic fingerprint pattern in the solid-state NMR spectra. 相似文献