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31.
Cadmium (Cd) is toxic to plants, animals, and humans. However, different plant species growing on the same soil may have very different shoot Cd concentrations depending on properties such as size of the root system, Cd net influx, shoot‐growth rate, Cd translocation from root to shoot, and the ability to affect Cd availability in the soil. To investigate possible reasons for different shoot Cd concentrations maize, sunflower, flax, and spinach were grown on an acid sandy soil (pH<$>_{{\rm{(CaCl}}_{\rm{2}} {\rm)}<$> 4.5, and Corg 2.8%) in a growth chamber with Cd additions as Cd(NO3)2 of none, 14, and 40 μmol (kg soil)–1 resulting in Cd soil‐solution concentrations of 0.04, 0.68, and 2.5 μM. Only the high Cd addition caused a significant growth reduction of flax and spinach. The shoot Cd concentration was up to 30 times higher in spinach than in maize; the other species were intermediate. Of the plant properties studied only the variation of the Cd net influx explained the differences in shoot Cd concentrations. This was due to a decreased (maize, sunflower) or increased (flax) Cd concentration in soil solution or more effective uptake kinetics (spinach). 相似文献
32.
Vladimir ?d��mal Jiri Smol��k Kostas Eleftheriadis Zdenek Wagner Christos Housiadas Nikos Mihalopoulos Pavel Miku?ka Zbynek Ve?e?a Ilias Kopanakis Mihalis Lazaridis 《Water, air, and soil pollution》2011,214(1-4):133-146
Measurements of number size distributions of submicron aerosols have been performed at the Eastern part of Mediterranean as part of an extensive measurement campaign to study photo-oxidants and aerosols (SUB-AERO Project). The measurements were made at the Finokalia station on the island of Crete (Greece) and onboard the research vessel ??Aegaeon??. Two campaigns were performed during July 2000 and January 2001 using two scanning mobility particle sizers. The particle distributions measured in the range between 7.8 < d p < 327 nm during the summer measurements and between 7.5 < d p < 316 nm during the winter measurements, where d p is the mobility particle diameter. The concentration of ultrafine particles (7.5 < d p < 30 nm) was higher during the winter period and varied mainly between 5 × 101 and 2 × 103?cm?3 with concentration peak values for this mode exceeding 1 × 104?cm?3. During the summer campaign, an average number concentration of 1 × 102?cm?3 at Finokalia and about 5 × 101?cm?3 aboard the ??Aegaeon?? vessel was measured. An average concentration of 1 × 103?cm?3 was measured for the particles in the size range between 30 and 100 nm, whereas in the size range 100?C300 nm, the measured concentration ranged between 1 × 102 and 5 × 103?cm?3. Diurnal patterns in number concentrations were observed in connection with the transport of air masses and local sources. During the winter period, three nucleation events were observed in connection with the appearance of a particle mode at 20 nm. 相似文献
33.
Journal of Plant Diseases and Protection - In the present study we examined the effect of the presence of wheat bugs (Eurygaster spp. and Aelia spp.) on wheat on the mortality, progeny production... 相似文献
34.
Christos Noulas Juan M. Herrera Ioannis Alexiou Theodore Karyotis Markus Liedgens Peter Stamp 《Journal of plant nutrition》2014,37(7):1012-1024
Efficient use of nitrogen (N) by wheat crop and hence prevention of possible contamination of ground and surface waters by nitrates has aroused environmental concerns. The present study was conducted in drainage lysimeters for three years (1998–2000) to identify whether spring wheat genotypes (Triticum aestivum L.) that differ in N-related traits differ in N leaching and to relate parameters of N use efficiency (NUE) with parameters of N leaching. For this reason two spring wheat cultivars (‘Albis’ and ‘Toronit’) and an experimental line (‘L94491’) were grown under low (20 kg N ha?1) and ample N supply (270 kg N ha?1). The genotypes varied in parameters of NUE but not in N leaching. Grain yield of the high-protein line (‘L94491’) was, on average, 11% lower than that of ‘Toronit’ but among genotypes had significantly higher N in the grain (%), grain N yield, and N harvest index. Nitrogen lost through leaching was considerably low (0.42–0.52 g m?2) mainly due to low volume of percolating water or the ability of the genotypes to efficiently exploit soil mineral N. There were no clear relationships between N-related genotype traits and N leaching, but across all treatments significantly negative correlations between volume of leachate and the amount of N in the total biomass and grain N yield existed. 相似文献
35.
Kafas P Kafas G Manafis K Stavrianos C 《Pakistan journal of biological sciences: PJBS》2008,11(3):493-495
Osteomyelitis as a medical term defining a specific type of infection may be classified in acute and chronic form. In our case an acute mandibular osteomyelitis is reported with evaluation of the clinical and histological examination. The biological course of the disease determined on that basis. The significance of this report focused on the early diagnosis and the possible need for bone biopsy. 相似文献
36.
Several extracts of Origanum dictamnus, an endemic plant of Greece growing only in the island of Crete and the bioassay-directed isolated ursolic acid, were tested in vitro against the P388 (murine leukemia) and the human bronchial epidermoid cancer NSCLC-N6 (non small cell lung cancer) cell lines. Both the initial dichloromethane extract and the isolated from it ursolic acid exhibited cytotoxic activity. Ursolic acid was also tested in vivo, on murine ascite leukemia P388, where it exhibited at a dose of 50 mg/kg a marginal antileukemic activity. 相似文献
37.
Solmaz Nadaf Fahmideh Mohammad Sadegh Allahyari Christos A. Damalas Zahara Daghighi Masouleh Mona Ghazi 《Paddy and Water Environment》2017,15(4):907-917
Factors affecting the adoption of double cropping were explored in rice farms of Fouman County of Guilan Province in northern Iran using artificial neural networks (ANNs), linear discriminant analysis (LDA), and logistic regression (LGR). Eleven factors (age, education, occupation, family size, type of farm ownership, distance to the agricultural service center, attending agricultural extension courses, use of financial resources and bank loans, number of domestic animals, area under cultivation, and social participation) were examined. An additional objective was to compare the ability of the three models in predicting the adoption of double cropping. ANNs showed an overall predictive power of 89.8%. LDA showed an overall predictive power of 83.2%, with seven of the eleven independent variables being effective on the adoption of double cropping. LGR indicated an overall predictive power of 87.6%, with eight of the eleven independent variables being effective on the adoption of double-rice cropping. ANNs showed higher power than LGR and LDA in predicting the adoption of double cropping. Based on all three methods used for analysis, the most important independent variables were social participation and area under cultivation (positive factors) as well as distance to the agricultural service center and family members (negative factors). Establishment of cooperatives or other kinds of farmers’ associations to foster social participation could motivate adoption of double cropping, particularly among small-scale farmers. To increase agricultural services, more local centers should be created in rural areas. The government should promote double cropping through effective incentives and technology transfer to small-scale farmers. 相似文献
38.
Th. Karyotis C. Iliadis Ch. Noulas Th. Mitsibonas 《Journal of Agronomy and Crop Science》2003,189(6):402-408
The aim of the present study was to compare the potential seed yield of eight quinoa varieties, to explore their mineral composition of seeds and to identify superior varieties in two locations with different soil properties. Compared with neutral soil conditions, seed yield in the marginal (saline–sodic) soil was decreased by 45 %. Under the latter soil conditions seed yield was negatively correlated with crop density, indicating that a considerable yield loss was due to poor and uneven plant density caused by adverse soil properties. Among the varieties, ‘RU–5–PQCIP–DANIDA–UNA’ produced the highest seed yield (>20 dt ha?1) when grown under neutral soil conditions. Under marginal conditions, the above‐mentioned variety and ‘N 407’ produced seed yields up to 10 dt ha?1 whereas the rest reached yields of only about 5 dt ha?1. The majority of the varieties accumulated significantly more protein (20 %) in the seeds under saline–sodic soil conditions (lower yielding environment). The varieties originated from South America were superior in accumulating protein in the seeds at both locations. Mineral contents of calcium (Ca), magnesium (Mg), zinc (Zn) and manganese (Mn) in the seeds were significantly higher in the neutral soil. No differences were found for phosphorous (P), iron (Fe), copper (Cu) and boron (B) between the two locations. The South American varieties were again superior in mineral composition. Adaptation of certain quinoa varieties even under marginal environments seems promising for seed production and/or protein and mineral content in the seeds. Agronomic data are needed in a due course, over a higher number of locations and/or various climatic conditions. 相似文献
39.
40.
Vasilios Samaras Christos D. Tsadilas Stamatis Stamatiadis Stephen Nortcliff 《植物养料与土壤学杂志》2010,173(2):252-259
The effects of biosolids from tomato processing on soil properties and wheat growth were investigated in an Alfisol from central Greece. Biosolids were mixed with soil from the surface (Ap) or subsurface (Bt) horizon in plastic containers at rates of 1%, 5%, and 10% by dry weight (d.w.; equivalent to 10, 50, and 100 Mg ha–1). Biosolid treatments were compared to an NH4Cl application (50 mg N kg–1) and an untreated control in (1) a 102 d incubation experiment at 28°C to determine biosolid nitrification potential and (2) a 45 d outdoor experiment to evaluate effects on soil fertility and wheat growth. Mineralization of biosolids in the incubation experiment resulted in accumulation of nitrate‐N and indicated that biosolids were able to supply N that was in excess of crop needs in treatments of 5% and 10%. After 45 d of wheat growth, available soil nutrients (N, P) and P uptake by wheat were distinctly lower in the Bt than in the Ap horizon. However, soil pH, electrical conductivity, organic matter, total N, nitrate‐N, extractable P, and exchangeable K increased with increasing rate of biosolid application in both soils. These were followed by corresponding increases in wheat nutrient uptake and biomass production, thus demonstrating the importance of this organic material for sustaining production in soils of low immediate fertility. Compared to the NH4Cl treatment (50 kg N ha–1 equivalent), biosolid application rates of 5% and 10% had higher available soil nutrients, similar or higher nutrient uptake and higher wheat biomass. But only an application of 10% biosolids provided sufficient N levels for wheat in the surface soil, and even higher applications were required for providing sufficient N and P in the Bt horizon. 相似文献