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排序方式: 共有152条查询结果,搜索用时 31 毫秒
71.
von Grotthuss M Wyrwicz LS Pas J Rychlewski L 《Science (New York, N.Y.)》2004,304(5677):1597-9; author reply 1597-9
72.
Sophie Cornu Saskia Keesstra Antonio Bispo Maria Fantappie Fenny van Egmond Bozena Smreczak Rafał Wawer Lenka Pavlů Jaroslava Sobocká Zsófia Bakacsi Kinga Farkas-Iványi Sándor Molnár Anders Bjørn Møller Sevinc Madenoglu Dalia Feiziene Katrien Oorts Florian Schneider Maria da Conceição Gonçalves Raquel Mano Gina Garland Rastislav Skalský Lilian O'Sullivan Raimonds Kasparinskis Claire Chenu 《European Journal of Soil Science》2023,74(4):e13398
At the European scale, soil characteristics are needed to evaluate soil quality, soil health and soil-based ecosystem services in the context of the European Green Deal. While some soil databases exist at the European scale, a much larger wealth of data is present in individual European countries, allowing a more detailed soil assessment. There is thus an urgent and crucial need to combine these data at the European scale. In the frame of a large European Joint Programme on agricultural soils launched by the European Commission, a survey was conducted in the spring of 2020, in the 24 European participating countries to assess the existing soil data sources, focusing on agricultural soils. The survey will become a contribution to the European Soil Observatory, launched in December 2020, which aims to collect metadata of soil databases related to all kind of land uses, including forest and urban soils. Based upon a comprehensive questionnaire, 170 soil databases were identified at local, regional and national scales. Soil parameters were divided into five groups: (1) main soil parameters according to the Global Soil Map specifications; (2) other soil chemical parameters; (3) other physical parameters; (4) other pedological parameters; and (5) soil biological features. A classification based on the environmental zones of Europe was used to distinguish the climatic zones. This survey shows that while most of the main pedological and chemical parameters are included in more than 70% of the country soil databases, water content, contamination with organic pollutants, and biological parameters are the least frequently reported parameters. Such differences will have consequences when developing an EU policy on soil health as proposed under the EU soil strategy for 2023 and using the data to derive soil health indicators. Many differences in the methods used in collecting, preparing, and analysing the soils were found, thus requiring harmonization procedures and more cooperation among countries and with the EU to use the data at the European scale. In addition, choosing harmonized and useful interpretation and threshold values for EU soil indicators may be challenging due to the different methods used and the wide variety of soil land-use and climate combinations influencing possible thresholds. The temporal scale of the soil databases reported is also extremely wide, starting from the '20s of the 20th century. 相似文献
73.
Anna MAZUR-PCZKA Grzegorz PCZKA Joanna KOSTECKA Kevin R. BUTT Marcin JAROMIN Mariola GARCZYSKA Agnieszka PODOLAK 《土壤圈》2021,31(3):391-397
As ecosystem engineers, earthworms play a key role in the soil environment. However, due to increasing anthropogenic pressure, soil organisms,including earthworms, are being threatened by habitat loss. In this study, we undertook a qualitative and quantitative investigation of earthworms of the family Lumbricidae in four types of Carpathian beech woodland(Fagetum carpaticum), characterized by their understory vegetation(I, F. c. festucetosum drymejae; II, F. c. typicum; III, F. c. lunarietosum; and IV, F. c. allietosum), in the Bieszczady National Park(Eastern Carpathians, Southeast Poland). At each investigated site, soil monoliths(25 cm × 25 cm × 25 cm) were examined by hand sorting. Earthworms were expelled from deep soil layers using a weak formalin solution(0.4%). Depending on the phytocoenosis, 7 species of Lumbricidae were identified at each of the sites I, II, and III and 10 at site IV. Site IV(F. c. allietosum) differed significantly(P 0.05) from the other three sites with respect to earthworm biomass(59.71 ± 39.53 g m~(-2))and the Shannon-Wiener diversity index(0.52 ± 0.12). Although present three decades ago, the deep-burrowing species Octodrilus transpadanus and the litter-dwelling species Dendrobaena octaedra were not found at site IV in the present study. We suspect that these two species may have been displaced by the invasive Lumbricus terrestris, which was not found at the same site in the 1980 s. Such observations warrant further investigation to verify the predicted effects of an invasive earthworm, including the potential effects on soils and other fauna and flora, which have been documented in numerous countries. 相似文献
74.
Klajn R Bishop KJ Fialkowski M Paszewski M Campbell CJ Gray TP Grzybowski BA 《Science (New York, N.Y.)》2007,316(5822):261-264
Deformable, spherical aggregates of metal nanoparticles connected by long-chain dithiol ligands self-assemble into nanostructured materials of macroscopic dimensions. These materials are plastic and moldable against arbitrarily shaped masters and can be thermally hardened into polycrystalline metal structures of controllable porosity. In addition, in both plastic and hardened states, the assemblies are electrically conductive and exhibit Ohmic characteristics down to approximately 20 volts per meter. The self-assembly method leading to such materials is applicable both to pure metals and to bimetallic structures of various elemental compositions. 相似文献
75.
Marcin Polak Jarosław Wiącek Marek Kucharczyk Robert Orzechowski 《European Journal of Forest Research》2013,132(5-6):931-941
The very rapid development of the road infrastructure in recent years has adversely affected the natural environment. The main effects of this have been the loss or deteriorating quality of habitats, the mortality of animals due to collisions with road vehicles, the withdrawal of birds as a result of disturbance and excessive noise in the neighbourhood of roads. In this study, we attempted to define the influence of a busy road on a breeding community of woodland birds. Individuals were counted using the point method at 54 observation points located at three various distances (60, 310, 560 m) from the road. At each point, we determined the habitat parameters and the intensity of noise. In total, 995 individuals of 39 species were recorded on the study plot. This study showed that the area was homogeneous with respect to habitat. The number of birds per point increased with distance from the road. Species diversity was lower near the road. The density of nine common species increased with distance from the road. Great Tit Parus major and Song Thrush Turdus philomelos preferred the neighbourhood of the road, whereas the numbers of the other species were the highest in the middle row of points. The number and species diversity of birds were correlated with the pattern of sound propagation across our study area. Our results showed that the species particularly sensitive to road traffic were those nesting near the ground and with low-frequency calls. 相似文献
76.
Saeed Rauf Maria Zaharieva Marilyn L Warburton ZHANG Ping-zhi Abdullah M AL-Sadi Farghama Khalil Marcin Kozak Sultan A Tariq 《农业科学学报》2015,14(8):1447-1474
Most yield progress obtained through the so called "Green Revolution", particularly in the irrigated areas of Asia, has reached a limit, and major resistance genes are quickly overcome by the appearance of new strains of disease causing organisms.New plant stresses due to a changing environment are difficult to breed for as quickly as the changes occur.There is consequently a continual need for new research programs and breeding strategies aimed at improving yield potential, abiotic stress tolerance and resistance to new, major pests and diseases.Recent advances in plant breeding encompass novel methods of expanding genetic variability and selecting for recombinants, including the development of synthetic hexaploid, hybrid and transgenic wheats.In addition, the use of molecular approaches such as quantitative trait locus(QTL) and association mapping may increase the possibility of directly selecting positive chromosomal regions linked with natural variation for grain yield and stress resistance.The present article reviews the potential contribution of these new approaches and tools to the improvement of wheat yield in farmer's fields, with a special emphasis on the Asian countries, which are major wheat producers, and contain the highest concentration of resource-poor wheat farmers. 相似文献
77.
78.
Piesova E Makova Z Levkut M Faixova Z Pistl J Marcin A Levkut M 《Research in veterinary science》2012,93(3):1307-1308
We investigated the effects of dietary addition of sage extract on the biochemical parameters, weight of some body organs and changes in the counts of Salmonella Enteritidis PT4 (SE) in experimentally infected chickens. The following diets were used: basal diet, basal diet with addition of an extract of Salvia officinalis L. (S), basal diet and SE, and basal diet and S and SE (SSE). Compared to the SE group, sage extract in the SSE group decreased activities of ALP and ALT and concentrations of glucose and bilirubin on the 4th day post inoculation (p.i.). However, on the 18th day p.i., lower levels of bilirubin and ALT activity only were detected. Addition of sage extract to the diets decreased the counts of Salmonella in the liver, spleen and caecum at both sampling times, along with lower production of mucus in the chickens' intestines. Our results suggest that the addition of sage extract to the diet could be effective in protecting SE-infected chickens. 相似文献
79.
80.
Katarzyna Pawłowska Maciej Kuligowski Iwona Jasińska-Kuligowska Marcin Kidoń Aleksander Siger Magdalena Rudzińska Jacek Nowak 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(3):196-202
The increasing demand for cocoa and search for ingredients rich in bioactive compounds encouraged us to investigate the possibility of replacing it by carob powder in the muffins containing soy beans, sesame oil and flaxseeds. There was 5% addition of carob or cocoa powder to the individual doughs. The muffins with the addition of carob were characterized by improved antiradical activity (by 36% - 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) method, by 83% - 2,2-diphenyl-1-picrylhydrazyl (DPPH) method), higher content of genistein (18%) and total phytosterols (17%) in the dry mass. The color differences in the carob muffins crusts were not perceptible by consumers (ΔE?=?0.70 for crust, ΔE?=?5.6 for crumb) and their taste was found to be less bitter and sweeter than the taste of cocoa muffins. Moreover, the addition of carob powder as well as cocoa powder resulted in good sensory quality. The high content of phytosterols, genistein and improved antiradical properties proved carob to be a source of bioactive compounds. The results show that carob powder may be used as valuable alternative muffin ingredient to cocoa. 相似文献