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41.
42.
Field experiments were carried out in the 2004 and 2005 growing seasons on drip irrigated dwarf green beans (Phaseolus vulgaris, humilis). Soil water content (SWC), spectral reflectance and yield were monitored. Based on these data crop evapotranspiration (ETc), soil water deficit index (SWDI), water use efficiency (WUE) and four separate spectral indexes were calculated. In order to determine use opportunities of spectral indexes for estimation of yield, SWDI and WUE, some statistical analyzes were made. Results showed that spectral indexes could be used for monitoring of yield, SWDI and WUE. Especially, Soil Adjusted Vegetation Index (SAVI) had the highest correlations with all three of the parameters. The estimation procedure which was given in this study has a potential use either during, or at the end of the growing season. Estimated values of WUE and SWDI were 3.2 (kg m?3) and 0.12, respectively, through SAVI and the given procedure, indicates the optimal water use and yield conditions for dwarf green beans. At this situation, probably ETc was 580 mm and yield was 25.5 t ha?1.  相似文献   
43.
This study aimed to evaluate the effects of juniper essential oil on the growth performance, rumen fermentation parameters, rumen protozoa population, blood antioxidant enzyme parameters and faecal content in growing Saanen kids. Thirty‐six male Saanen kids (36 ± 14 days of age) were used in the study. Each group consisted of 9 kids. The control group (G1) was fed with a diet that consisted of the above concentrated feed and oat hay, whereas the experimental groups consumed the same diet but with the concentrated feed uniformly sprayed with juniper essential oil 0.4 ml/kg (G2), 0.8 ml/kg (G3) or 2 ml/kg (G4). There were no differences (p > 0.05) in live weight, live weight gain or feed consumption between the control and experimental groups. There was a significant improvement (p < 0.05) in feed efficiency in the G3 group. There were no differences in the rumen pH, rumen volatile fatty acid (VFA) profile or faecal pH of the control and experimental groups. The rumen NH3N values were similar at the middle and end of the experiment, but at the start of the experiment, the rumen NH3N values differed between the control and experimental groups (p < 0.05). The faecal score value was significantly (p < 0.05) decreased in the experimental groups. The addition of juniper essential oil supplementation to the rations caused significant effects on the kids’ antioxidant blood parameters. Although the superoxide dismutase (SOD) activity, total antioxidant capacity (TAC) and catalase values were significantly (p < 0.05) increased in the experimental groups (G2, G3 and G4), especially group G4, the blood glutathione peroxidase (GPX) value significantly decreased in the experimental groups. The results of this study suggest that supplementation of juniper oil is more effective on antioxidant parameters than on performance parameters and may be used as a natural antioxidant product.  相似文献   
44.
Due to genetic diversity within and among switchgrass (Panicum virgatum), there may be genotype x environment and management-induced differences among secondary cell walls. Consequently, two separate experiments were conducted to determine feedstock variance using near-infrared spectrometry (NIRS). One experiment tested legume-intercrops [red clover (RC; Trifolium pratense), crimson clover (CC; Trifolium incarnatum), hairy vetch (HV; Vicia villosa), and partridge pea (PP; Chamaechrista fasciculata)], nitrogen (N) fertilization (0, 67, and 135 kg-N ha?1), and location impacts on characteristics. The second one determined on-farm bale variance within and across locations. Clustering NIRS data indicated that chemical signatures differed among locations and N-levels, but less so among intercrops. Results suggest that homogeneity may vary within a region responsible for supplying biomass to a biorefinery. Thus, conversion efficiencies and enzymatic requirements for ethanol production may be affected. Consequently, legumes may displace inorganic-N with minimal compositional changes, whereas location and N-level influence feedstock quality and recalcitrance level to a greater extent.  相似文献   
45.
The objective of this study was to determine whether differences in canopy structure and litter composition affect soil characteristics and microbial activity in oak versus mixed fir-beech stands. Mean litter biomass was greater in mixed fir-beech stands (51.9t ha−1) compared to oak stands (15.7t ha−1). Canopy leaf area was also significantly larger in mixed stands (1.96m2 m−2) than in oak stands (1.73m2 m−2). Soil organic carbon (C org) and moisture were greater in mixed fir-beech stands, probably as a result of increased cover. Soil microbial biomass carbon (C mic), nitrogen (N mic), and total soil nitrogen (N tot) increased slightly in the mixed stand, although this difference was not significant. Overall, mixed stands showed a higher mean C org/N tot ratio (22.73) compared to oak stands (16.39), indicating relatively low rate of carbon mineralization. In addition, the percentage of organic C present as C mic in the surface soil decreased from 3.17% in the oak stand to 2.26% in the mixed stand, suggesting that fir-beech litter may be less suitable as a microbial substrate than oak litter.  相似文献   
46.
The basic aim of the sprinkler irrigation method, as in other irrigation methods, is to apply irrigation water as uniformly as possible to the root zone. The uniform distribution of the applied water in sprinkler irrigation depends on factors such as sprinkler type, number and size of nozzles, arrangement of sprinklers, working pressure and the speed and direction of the wind. Sprinkler and lateral spacing should be determined by also taking the speed and direction of the wind into consideration. The aim of this study was to determine the application limits and the curves of water distribution under different working pressures, spatial arrangement and nozzle diameters under field conditions of some irrigation sprinklers which are widely used in Turkey. The objective was to determine the most appropriate system arrangement by using a computer program called CATCH3D. Five sprinklers were tested in the experimental area of Ondokuz Mayis University Campus and their water distribution characteristics identified. The most suitable operating parameters for Bereket 3: 12 x 18 m, Bereket 2: 12 x 18 m, Egeyildiz 6 x 18m, Goktepe 6 x 12 m and for Atesler sprinkler 12 x 18 m arrangement type were determined.  相似文献   
47.
A field experiment was conducted during summer season of 2005 at the Research Station (altitude 180 m above sea level, 41 degrees 21' N and 36 degrees 15'E) Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey. Experiment consisted of three irrigation levels and a non-irrigation level. Drip irrigation treatments consisted of three soil water deficits in the 90 cm soil profile depth was replenished to field capacity. Irrigation treatments were A: no irrigation, B: irrigation at 50% of available soil water capacity, C: irrigation at 30% of available soil water capacity, D: irrigation at 15% of available soil water capacity. The average seasonal water use values ranged from 257.14 to 285.71 mm in corn treatments. Irrigation frequencies (intervals) significantly affected corn crop yields. The average corn grain yields varied from 7.98 to 29.16 t ha(-1). The treatment D was recorded significantly higher corn grain yield 29.16 t ha(-1) compared to B (21.59 t ha(-1)); C (19.15 t ha(-1)) and A (7.98 t ha(-1)), respectively. According to research results, the maximum corn grain yield was obtained when the corn plants were irrigated at 15% of available soil water capacity to field capacity.  相似文献   
48.
Abstract – Understanding population regulation in juvenile salmonids requires distinguishing the effects of intrinsic (size, behaviour) and extrinsic (food, competition) factors. To examine the relative influence of these variables on juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Salmon River drainage (ID, USA), we examined diel differences in foraging microhabitats, behaviour and consumption in two areas with consistent differences in parr‐to‐smolt survival. In lower Big Creek (LBC, high‐survival area) and upper Big Creek (UBC, low‐survival area), we observed fish by snorkelling, recording length, behaviour (foraging rate and aggression) and physical (depth, velocity, cover, temperature) and biotic (density, size and species of neighbouring fish) microhabitat features. Stomach contents were extracted to estimate consumption. Depth and temperature were greater in LBC, where Chinook salmon were significantly larger and present at lower densities. Fish in LBC exhibited higher foraging activity during the day than night, but there were no size differences between day and night foragers. In UBC, a higher density area, foraging behaviour did not change between day and night, although the smallest size classes did not forage nocturnally. Regression models that integrated physical and biotic variables suggested that physical factors influenced foraging in both areas, but competition also affected foraging in UBC. Our results demonstrate that fish from low‐ and high‐survival populations in Big Creek are exposed to different physical and biological influences during their first growth season, which are reflected in different diel foraging behaviours.  相似文献   
49.
In this study, N-(2-aminoethyl)salicylaldimine bonded silica gel was synthesized and characterized using Fourier transform infrared and C, H, N elemental analysis. The analytical conditions such as the pH and volume of the solution, flow rates of the sample solution and the type of eluent to achieve the simultaneous preconcentration of Cu(II), Ni(II), Cd(II) and Zn(II) were optimised using the modified silica gel loaded column using a solid phase extraction technique. Samples (50?C500?ml) containing metal ions at optimal pH of 8 were passed through the column filled with the modified silica gel at 7?ml min?1 and then elution was achieved using 5?ml of 0.25?M HCl. The concentrations of metal ions in the eluates were determined using flame atomic absorption spectrometry (FAAS). The effects of matrix ions were also studied and none of the major ions interfered to the proposed method. The accuracy of the developed method was validated using a certified reference water sample (Ontario Lake water, NWTMDA-54.4). The method was successfully applied to the analysis of various natural water samples. The adsorption capacities of the modified silica gel for Cu(II), Ni(II), Cd(II) and Zn(II) ions were determined and found to be 0.332, 0.261, 0.130 and 0.375?mmol g?1, respectively.  相似文献   
50.
This case series describes novel findings associated with heat stress in 15 cases in South American camelids that had no pre-existing illnesses and which had clinical signs of illness after exposure to a warm environment. Novel findings include decreased packed cell volume and albumin concentration and mild spinal axonal degeneration. Heat stress should be considered in weak camelids with a history of hyperthermia.  相似文献   
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