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61.
Jose Luiz Stape Dan Binkley Michael G. Ryan Sebastiao Fonseca Rodolfo A. Loos Ernesto N. Takahashi Claudio R. Silva Sergio R. Silva Rodrigo E. Hakamada Jose Mario de A. Ferreira Augusto M.N. Lima Jose Luiz Gava Fernando P. Leite Helder B. Andrade Jacyr M. Alves Gualter G.C. Silva Moises R. Azevedo 《Forest Ecology and Management》2010
We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2 Mg ha−1 yr−1, about 33 m3 ha−1 yr−1) than yields achieved with current operational rates of fertilization (22.6 Mg ha−1 yr−1, about 46 m3 ha−1 yr−1). Fertilization beyond current operational rates did not increase growth, whereas irrigation raised growth by about 30% (to 30.6 Mg ha−1 yr−1, about 62 m3 ha−1 yr−1). The potential biological productivity (current annual increment) of the plantations was about one-third greater than these values, if based only on the period after achieving full canopies. The biological potential productivity was even greater if based only on the full-canopy period during the wet season, indicating that the maximum biological productivity across the sites (with irrigation, during the wet season) would be about 42 Mg ha−1 yr−1 (83 m3 ha−1 yr−1). Stands with uniform structure (trees in plots planted in a single day) showed 13% greater growth than stands with higher heterogeneity of tree sizes (owing to a staggered planting time of up to 80 days). Higher water supply increased growth and also delayed by about 1 year the point where current annual increment and mean annual increment intersected, indicating opportunities for lengthening rotations for more productive treatments as well as the influence of year-to-year climate variations on optimal rotations periods. The growth response to treatments after canopy closure (mid-rotation) related well with full-rotation responses, offering an early opportunity for estimating whole-rotation yields. These results underscore the importance of resource supply, the efficiency of resource use, and stand uniformity in setting the bounds for productivity, and provide a baseline for evaluating the productivity achieved in operational plantations. The BEPP Project showed that water supply is the key resource determining levels of plantation productivity in Brazil. Future collaboration between scientists working on silviculture and genetics should lead to new insights on the mechanisms connecting water and growth, leading to improved matching of sites, clones, and silviculture. 相似文献
62.
Angela LO MONACO Luigi TODARO Mara SARLATTO Raffaello SPINA Luca CALIENNO Rodolfo PICCHIO 《中国林学(英文版)》2011,13(4):276-284
This study aims to investigate wood density at different levels of moisture, basic density and shrinkage of timber from Turkey oak (Quercus cerris L.) coppice forests growing in Central Italy. We also studied the variability in density in the trees within and among sites. Density shows no significant statistical differences in the tested population. A higher variability in the shrinkage than in the density was found. Wood moisture is referred to as dry mass and fresh mass, which is related to many performance characteristics of wood, i.e., energy production. Trends in moisture and water content were studied because these physical parameters play an important role in the specific area of firewood which requires an accurate estimation of mass, volume and energy content. This work is a contribution to improve xylo-energy estimates of small and medium forestry issues. 相似文献
63.
Lourival Ferreira Cavalcante Ítalo Herbert Lucena Cavalcante Francisco Rodolfo Júnior Márkilla Zunete Beckmann-Cavalcante Gaudêncio Pereira dos Santos 《Journal of plant nutrition》2013,36(2):176-191
Biofertilizers instead of synthetic chemicals are known to improve plant growth through the supply of plant nutrients and they may help sustaining environmental health and soil productivity. An experiment was carried out to evaluate fruit yield and macronutrient foliar contents of yellow passion fruit plants (Passiflora edulis) as a function of biofertilizers and nitrogen-phosphorus-potassium (N-P-K) fertilizing in Brazil (2005–2007). The experimental design was randomized in blocks with treatments, which were distributed in a factorial arrangement (3 × 2) referring to biofertilizer application [without biofertilizer, simple biofertilizer and enriched biofertilizer] and mineral fertilizing with NPK (fertilized and non-fertilized), with three replications of nine plants. Nutritional status of yellow passion fruit is affected by biofertilizer. Simple biofertilizer promotes optimum supplies of phosphorus, calcium and sulfur, while enriched biofertilizer promotes optimum supplies of phosphorus, potassium, calcium and sulfur. Both biofertilizers stimulated fruit yield, with results above Brazilian average. 相似文献
64.
Determining the drift potential of Venturi nozzles compared with standard nozzles across three insecticide spray solutions in a wind tunnel 下载免费PDF全文
65.
Rodolfo Claro Kenyon C. Lindeman Andrew S. Kough Claire B. Paris 《Fisheries Oceanography》2019,28(1):33-42
The ability of larvae to move beyond the spatial range of adult migrations can be critical to the resilience of populations that aggregate to spawn. We reviewed the literature and unpublished information on larval transport modeling, reef fish spawning aggregations, and marine protected area (MPA) management to identify alternatives for Cuban spawning site conservation. Larval transport information is available at annual and decadal scales for eight Cuban sites for five species of snappers. Connectivity patterns were examined: (a) within Cuban regions, (b) among Cuban regions, and (c) among other countries. We compared this information with the distribution of protected areas relative to spawning sites, site management attributes, and potential alternatives. Of eight focal spawning sites, seven are in protected areas and one is proposed. Southeast and north‐central Cuba had highest estimated within‐region retention levels. Southwest and northwest sites exported relatively more larvae out‐of‐region. Southern regions produced larvae that reached Jamaica, the Cayman Islands and Haiti. All northern regions can export larvae to the southern Bahamas. The regions and sites within are geomorphologically diverse with variable fishing and socio‐economic attributes. Information on stock status and protected area efficacy is limited and field assessments of aggregation status are needed for multispecies spawning sites. Few management plans address spawning conservation or network connectivity opportunities for MPAs. An alternative is development of one or more regional workgroups of protected area specialists, fishery scientists, expert fishers, and other stakeholders. Temporal closures of fisheries before and during spawning season could also amplify effectiveness of current gear‐ and zoning‐based management tools. 相似文献
66.
67.
Yenitze E. Fimbres‐Acedo Rosalía Servín‐Villegas Rodolfo Garza‐Torres Masato Endo Kevin M. Fitzsimmons Maurício G.C. Emerenciano Paola Magalln‐Servín Melissa Lpez‐Vela Francisco J. Magalln‐Barajas 《Aquaculture Research》2020,51(10):4340-4360
Protein‐dependent aquaculture generates large amounts of nutrient‐rich residuals; a feasible way to develop sustainable production systems is to integrate Decoupled Aquaponic Systems (DAPS) with residual water bioprocesses, to combine Photoautotrophic Biofloc Technology (P‐BFT) aquaculture and hydroponic horticulture. This study describes the characteristics of residual water from Oreochromis niloticus aquaculture performed with P‐BFT inoculated with Chlorella microalgae, reared during the nursery (180 fish m3) and grow‐out (55 fish m3) phases. The experiment included five treatments: photoautotrophic BFT inoculated with Chlorella sp. (M), C. sorokiniana 2714 (CV), and C. sorokiniana 2805 (CS), and chemoautotrophic (Q) and heterotrophic (H) as controls. Elemental characteristics in liquid and solid residual fractions (15 macro‐ and micronutrients) were compared among treatments and against Hoagland & Arnon solution with hydroponics and used in Nutrient Film Technique (NFT) hydroponic horticulture including five plant species: lettuce (Lactuca sativa), pak‐choi (Brassica rapa subsp. chinensis), rocket (Eruca sativa), spinach (Spinacia oleracea) and basil (Ocimum basilicum). The physicochemical parameters were ideal for O. niloticus and plants. The relationship between N:P was ideal until weeks 16–22 in the photoautotrophic treatments, compared with hydroponic solutions. Micronutrient content was greater in the solid than a liquid fraction. The best BFT effluent regarding fish and plant growth was photoautotrophic treatments. Oreochromis niloticus BFT aquaculture in photoautotrophic mode using microalgae Chlorella inoculations provided residual water beneficial to hydroponic horticulture in DAPS located in coastal arid zones where freshwater is scarce, improving aquaculture performance and reusing water and nutrients. 相似文献
68.
Tauber E Zordan M Sandrelli F Pegoraro M Osterwalder N Breda C Daga A Selmin A Monger K Benna C Rosato E Kyriacou CP Costa R 《Science (New York, N.Y.)》2007,316(5833):1895-1898
Circadian and other natural clock-like endogenous rhythms may have evolved to anticipate regular temporal changes in the environment. We report that a mutation in the circadian clock gene timeless in Drosophila melanogaster has arisen and spread by natural selection relatively recently in Europe. We found that, when introduced into different genetic backgrounds, natural and artificial alleles of the timeless gene affect the incidence of diapause in response to changes in light and temperature. The natural mutant allele alters an important life history trait that may enhance the fly's adaptation to seasonal conditions. 相似文献
69.
Qualitative analysis of cartilaginous jaw element malformation in cultured yellowtail kingfish (Seriola lalandi) larvae 下载免费PDF全文
Betzabel Jara Marcelo Abarca Rodolfo Wilson Sebastián Krapivka Ana Mercado Ricardo Guiñez Lorena Marchant 《Aquaculture Research》2017,48(8):4420-4428
A central problem facing worldwide culture of yellowtail kingfish (Seriola lalandi) is the presence of skeletal malformations, including jaw deformities. This study presents a morphological characterization of normal and abnormal cartilage jaw structures during early larval development. Samples of 70–150 larvae were collected from three cohorts from 2 to 9 days post hatching, anaesthetized and fixed for cartilage staining. Cartilaginous components were defined clearly at four days post hatch (dph) (4.65 ± 0.05 mm total length), and abnormal jaw structures were detectable at this time. Jaw deformities observed included extension of Meckel's cartilage with or without ventral bending of the anterior tip, displacement of ceratohyal and hypohyal cartilage ventrally and below Meckel's cartilage, and shortening and dorsal flexion of the lower jaw. At 4 dph, between 44% and 47% of all larvae examined had jaw abnormalities. The contribution of each deformity to the total number of deformities was variable among the three cohorts examined. To compare shape difference accurately we performed an exploratory, landmark‐based geometric morphometric analysis using seven homologous landmarks. Larvae were classified into three jaw morphology groups. The geometric morphometric approach provides a useful tool to standardize classification of cartilage jaw abnormalities at early developmental larval stages. Early recognition of developing abnormalities is of importance for fish farmers in both improving fish selection efficiency and for evaluating effects of rearing parameters. 相似文献
70.
Ezequiel?Grondona Gerardo?Gatti Abel?G.?López Leonardo?Rodolfo?Sánchez Virginia?Rivero Oscar?Pessah María?P.?Zunino Andrés?A.?PonceEmail author 《Plant foods for human nutrition (Dordrecht, Netherlands)》2014,69(4):351-357
The aim of this study was to investigate the bioactivity of the essential oil isolated from Origanum vulgare L. (EOv). We analyzed the in vivo anti-inflammatory properties in a mouse-airway inflammation model and the in vitro antimicrobial activity, genotoxicity over the anaphase-telophase with the Allium cepa strain and its cytotoxicity/viability in A549 culture cells. In vivo, EOv modified the levels of tumor necrosis factor -α and viable activated macrophages and was capable to mitigate the effects of degradation of conjugated dienes. In vitro, EOv reduced the viability of cultured A549 cells as well as the mitotic index and a number of chromosomal aberrations; however, it did not change the number of phases. We found that EOv presents antimicrobial activity against different Gram (?) and (+) strains, measured by disc-diffusion test and confirmed with a more accurate method, the AutoCad software. We postulate that EOv presents antibacterial, antioxidant and chemopreventive properties and could be play an important role as bioprotector agent. 相似文献