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71.
Alfonso Calera Belmonte Anne M. Jochum AndrÉs Cuesta GarcÍa Amelia Montoro Rodríguez Prudencio López Fuster 《Irrigation and Drainage Systems》2005,19(3-4):337-353
Irrigation Advisory Services (IAS) are the natural management instruments to achieve a better efficiency in the use of water
for irrigation. IAS provide the farmers with irrigation scheduling information, based on crop water requirements for different
crops, and thus, help farmers to optimise production and cost-effectiveness. Current IAS rely on labour- and cost-intensive
field work, yet are unable to cover each plot in large areas at regular short time intervals. Earth observation (EO) is naturally
destined to fill this gap. It allows for efficiently monitoring crop water requirements and related parameters within each
field in extended areas. The incorporation of IT in the generation and distribution of information makes that information
easily available to IAS and to its associated farmers in a personalised way. Farmers can opt to receive a wide variety of
products, tailored to their needs and infrastructure, ranging from simple irrigation scheduling recommendation (irrigation
volume, time) to colour-coded images (providing quick intuitive information on the crop vigour within their plots), both on
PC and/or mobile phones.
This work is based on the project DEMETER (DEMonstration of Earth observation TEchnologies in Routine irrigation advisory
services), which assesses and demonstrates the EO- and IT-induced improvements in IAS day-to-day operations. This paper describes
the methodology and discusses examples of products. 相似文献
72.
José A. ARMENTEROS Jesús CARO Carlos SÁNCHEZ-GARCÍA Beatriz ARROYO José A. PÉREZ Vicente R. GAUDIOSO Emilio J. TIZADO 《Integrative zoology》2021,16(2):226-239
Provision of food and water is a widespread tool implemented around the world for the benefit of game and other wildlife, but factors affecting the use of food and water by non-target species are poorly known. We evaluated visits to feeders and water troughs by non-game species using camera-traps in two separate areas of Spain. Feeders and water troughs were either “protected” (when surrounded by more than 50% of shrubs/forest) or “open” (in the opposite case). A total of 18 948 photos from 5344 camera-trapping days depicted animals, and 75 species were identified. Feeders and water troughs were visited by target species (partridges and lagomorphs, 55.3% of visits) and non-target species (44.7% of visits). Among the latter, corvids were the most common (46.1% of visits), followed by rodents (26.8%), other birds (23.6%, mainly passerines), columbids (1.9%), and other species at minor percentages. The highest proportion of visiting days to feeders and water troughs was from corvids (0.173) followed by other-birds (0.109) and rodents (0.083); the lowest proportion was recorded for columbids (0.016). Use intensity and visit frequency of water troughs tripled that recorded in feeders, and visits to open feeders/troughs were approximately twice those to protected ones. In summary: feeders and water troughs targeting small game species are also used regularly by non-target ones; they should be set close to cover to optimize their use by non-target species that are not competitors of target species (though corvids may visit them); water availability should be prioritized where drought periods are expected. 相似文献
73.
EDUARDO FRAGA JOSÉ DANIEL BARREIRO ANA GOICOA LUCIANO ESPINO GEMMA FRAGA ANDRÉS BARREIRO 《Veterinary radiology & ultrasound》2011,52(3):323-329
Canine babesiosis is a tick‐borne disease with a worldwide distribution that can involve multiple organs and result in a wide variety of clinical manifestations. Our goal was to describe the sonographic changes occurring in 72 dogs naturally infected with babesiosis. Seven healthy Beagle dogs were used as a control group. The most common finding in all dogs was splenomegaly with a diffuse heterogenic parenchyma and generally reduced echogenicity. Diffuse hypoechoic hepatomegaly and bilaterally increased cortical echogenicity of the renal parenchyma were found more frequently in severe uncomplicated and complicated babesiosis groups. Mean renal resistive index and pulsatility index (PI) values were 0.66/1.35, 0.73/1.91, and 0.71/1.73 for mild uncomplicated, severe uncomplicated, and complicated babesiosis groups, respectively. A markedly increased PI for complicated and severe uncomplicated groups correlated with anemia and severity of renal damage. Ultrasonography can be an adjunct for diagnosis and monitoring canine babesiosis and its systemic complications. The detection of diffuse heterogeneous splenomegaly can support the diagnosis of Babesia infection, because of the high prevalence of this lesion in these patients. 相似文献
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76.
Fluorescence imaging was utilized to demonstrate the potential of blue-green fluorescence (BGF) and chlorophyll-a fluorescence (ChlF) to discriminate nitrogen (N), phosphorus (P), and potassium (K) deficiencies in sunflower plant showing similar growth inhibition. Only K-deficient leaves displayed significant increase of the BGF intensity. The epidermal UV-transmittance estimated by the ratio of ChlF intensities induced by UV and blue excitations (ChlFUV/ChlFBLUE) markedly decreased in both N- and P-deficient leaves but only in the latter that we observed significant decrease of the ratio of red and far-red ChlF intensities (RF/FRF) (that is inversely related to leaf chlorophyll concentration). The BGF increase in K-deficient was limited at leaf apex and margins and was spatially correlated to localized RF/FRF increases. Images analysis allows a better interpretation of the fluorescence changes by showing the spatial relationships between BGF, the ChlFUV/ChlFBLUE and the RF/FRF ratios that are indicative of physiological disturbances occurring in leaves of nutrient deficient plants. 相似文献
77.
JOSÉ MARTÍN GALLARDO José Carlos Escudero García Encarnación García Ceballos-Zúñiga Juan José Pérez-Regadera Pérez 《Aquaculture International》2006,14(1-2):163-170
Two physical factors light or substrate (fibre glass, artificial vegetation, gravel and mud) were determined in a 24 m long
artificial channel to have importance on the distribution of 33 tench 2+, mean size 11.8±0.9 cm S.L. For this purpose in five
trials tench could select between the half of the channel occupied by their preferred light intensity (inferior to 10 lux)
combined with the less preferred substrate (fibre glass) or the half with the combination of one of the substrates considered
and higher light conditions (40 lux). Fish preferred, with a 100% frequency, the optimal light-less preferred substrate when
compared with the combinations fibre glass, gravel and mud. When artificial vegetation was the substrate considered, tench
selected the combination preferred substrate – non-optimal light intensity with a 98.26±2.68% frequency. This result changed
when increasing light intensity up to 150 lux, avoiding the shading effect. We demonstrated that light has a bigger influence
than substrate in juvenile tench habitat selection under controlled conditions. 相似文献
78.
Vincent M. Maillard Gregory D. Boardman Justin E. Nyland David D. Kuhn 《Aquacultural Engineering》2005,33(4):271-284
Studies were conducted to characterize raceway water quality, effluent water quality, and waste solids within three, raceway-type trout farms. No significant differences were found in effluent water quality between the three farms during 7 months of monitoring. Average effluent quality over the course of the day was not found to be impaired. However, effluent quality was found to change significantly during times of feeding and harvesting. In a concrete/earthen-lined farm, normalized total suspended solids (TSS) concentrations were as high as 115 and 63 mg/l during harvesting and feeding events, respectively. Total Kjeldahl nitrogen (TKN) and ortho-phosphate (OP) also increased with higher TSS loads. The majority of particles (by weight) measured in effluent samples at all three farms were evenly divided between the smallest range (1.5–30 μm) and the largest (>210 μm). For settled sludge samples, the majority of the particles were in the size range of 1.5–30 μm. Particle size in the raceway was positively correlated with fish size during feeding events, but this correlation dissipated during the 4-h period after feeding. The accumulation and characteristics of sludge in a sediment trap were also monitored over a 22-day period. 相似文献
79.
Determination of anthelmintic efficacy against equine cyathostomins and Parascaris equorum in France
T. Geurden J.‐M. Betsch K. Maillard B. Vanimisetti M. D'Espois B. Besognet 《Equine Veterinary Education》2013,25(6):304-307
This article reports the results of a faecal egg count reduction test on 4 farms in France, as an integrated part of the routine deworming strategy against horse cyathostomins and Parascaris equorum. Treatment with fenbendazole (FBZ) or ivermectin (IVM) was evaluated in yearlings on Farms 1 and 2 and treatment with pyrantel embonate (PYR) was tested on Farms 3 and 4. Calculation of the arithmetic mean faecal egg count reduction and the 95% confidence intervals (95% CI) around the mean was performed using bootstrap analysis. For equine cyathostomins, resistance to FBZ was found with an arithmetic mean reduction of 48.8% (95% CI: 1.9–69.3%). On Farms 1 and 2, horses with reduced efficacy were identified. PYR was found to be effective against cyathostomins, with an arithmetic mean reduction of 95.3% (95% CI: 84.6–99.8%), as well as IVM (100%). For P. equorum, both FBZ and PYR were effective (100% reduction). The efficacy of IVM, however, was low (45.5%; 95% CI: 0–96.3%). These results confirm that FBZ resistance in equine cyathostomins is present in France and that anthelmintic resistance to IVM is present in P. equorum. This study underlines the necessity to evaluate the efficacy of horse deworming strategies on a regular basis under field conditions. 相似文献
80.