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81.
The purpose of the experiment is to research the effect of different rapeseed treatments feeding on activity of cellulose enzyme in sheep. Eight male adults of semi-fine wool sheep breeds with the same weight and permanent rumen cannulas were selected according to 4×4 Latin square design to determine the effect of different rapeseed treatment groups including crushed rapeseed, whole rapeseed, extruded rapeseed (dietary lipid content of =67 g · kg-1 ) and control group (dietary lipid content of =30 g · kg-1 ) on activity dynamic variation of ruminal celluolytic enzyme in sheep. The results showed that ruminal fluid pH matched up to the condition of fiber degradation and growth of cellulolytic bacterium when fed four diets; but there was significant difference (P0.05) for the activity of microcrystalline cellulose, glucanase, salicin enzyme involved in ruminal fiber degradation after fed 2, 4, 6 h.  相似文献   
82.
Combination of strategies involving germination-hydrothermal treatments and fractionation were adopted to separates the native and treated grain into coarse (bran & germ) and fine (endosperm) fractions. The inhibitory factors, polyphenol oxidase, and phytase activity were higher in coarse fractions. On treatment, the phytic acid content in the coarse fraction decreases significantly by 49% while polyphenols decreased 13% in the fine fraction and increased 6% in the coarse fraction. Galloyls reduced by 21% and 48% in the fine and coarse fraction while catechols increased by 74% in the fine fraction and reduced by 27% in the coarse fraction. In the fine fraction, the soluble and insoluble fibre increased by 27.8% and 28.7% while in the coarse fraction is reduced by 23.5% and 24.1%. The β-carotene content reduced slightly in the coarse fraction with no variation in the fine fraction. Iron bioaccessibility was enhanced from 1.79 to 5.7% in the fine fraction and 3.06–6.05% in the coarse fraction. Zinc bioaccessibility increased from 15.44 to 24.67% and 18.59–47.6% in the fine and coarse fraction, respectively. In the treated coarse fraction the iron-zinc bioaccessibility increased due to a significant reduction in phytic acid (49%), insoluble dietary fibre (24%), galloyls (48%) and catechols (27%).  相似文献   
83.
Land managers across the western United States are faced with selecting and applying tree-removal treatments on pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland-encroached sagebrush (Artemisia spp.) rangelands, but current understanding of long-term vegetation and hydrological responses of sagebrush sites to tree removal is inadequate for guiding management. This study applied a suite of vegetation and soil measures (0.5 ? 990 m2), small-plot rainfall simulations (0.5 m2), and overland flow experiments (9 m2) to quantify the effects of mechanical tree removal (tree cutting and mastication) on vegetation, runoff, and erosion at two mid- to late-succession woodland-encroached sagebrush sites in the Great Basin, United States, 9 yr after treatment. Low amounts of hillslope-scale shrub (3 ? 15%) and grass (7 ? 12%) canopy cover and extensive intercanopy (area between tree canopies) bare ground (69 ? 88% bare, 75% of area) in untreated areas at both sites facilitated high levels of runoff and sediment from high-intensity (102 mm ? h? 1, 45 min) rainfall simulations in interspaces (~ 45 mm runoff, 59 ? 381 g ? m? 2 sediment) between trees and shrubs and from concentrated overland flow experiments (15, 30, and 45 L ? min? 1, 8 min each) in the intercanopy (371 ? 501 L runoff, 2 342 ? 3 015 g sediment). Tree cutting increased hillslope-scale density of sagebrush by 5% and perennial grass cover by twofold at one site while tree cutting and mastication increased hillslope-scale sagebrush density by 36% and 16%, respectively, and perennial grass cover by threefold at a second more-degraded (initially more sparsely vegetated) site over nine growing seasons. Cover of cheatgrass (Bromus tectorum L.) was < 1% at the sites pretreatment and 1 ? 7% 9 yr after treatment. Bare ground remained high across both sites 9 yr after tree removal and was reduced by treatments solely at the more degraded site. Increases in hillslope-scale vegetation following tree removal had limited impact on runoff and erosion for rainfall simulations and concentrated flow experiments at both sites due to persistent high bare ground. The one exception was reduced runoff and erosion within the cut treatments for intercanopy plots with cut-downed-trees. The cut-downed-trees provided ample litter cover and tree debris at the ground surface to reduce the amount and erosive energy of concentrated overland flow. Trends in hillslope-scale vegetation responses to tree removal in this study demonstrate the effectiveness of mechanical treatments to reestablish sagebrush steppe vegetation without increasing cheatgrass for mid- to late-succession woodland-encroached sites along the warm-dry to cool-moist soil temperature ? moisture threshold in the Great Basin. Our results indicate improved hydrologic function through sagebrush steppe vegetation recruitment after mechanical tree removal on mid- to late-succession woodlands can require more than 9 yr. We anticipate intercanopy runoff and erosion rates will decrease over time at both sites as shrub and grass cover continue to increase, but follow-up tree removal will be needed to prevent pinyon and juniper recolonization. The low intercanopy runoff and erosion measured underneath isolated cut-downed-trees in this study clearly demonstrate that tree debris following mechanical treatments can effectively limit microsite-scale runoff and erosion over time where tree debris settles in good contact with the soil surface.  相似文献   
84.
85.
通过对比试验,研究不同茎段部位,不同药剂类型、处理浓度和浸泡时间等25种处理组合对木薯单芽扦插生根的影响。结果表明,0.05 g/L GGR处理1.5 h、0.5 g/L TDZ处理30 min、0.1 g/L ABT处理 30 min等3种药剂处理组合,采用茎段中部材料获得了较好的效果。  相似文献   
86.
Yellowing or bacteriosis is the most severe disease of Pleurotus eryngii, the mushroom commonly called “cardoncello” or “Ferula mushroom” in Italy. Two cropping cycles were performed with five commercial strains, to find out how acetic acid or hydrochloric acid solutions can be used to prevent or stop the disease. Pseudomonasreactans” and other fluorescent Pseudomonads were consistently isolated from symptomatic basidiomata. The Colony-Forming-Units of total bacteria, fluorescent Pseudomonads and fungi, found in casing soil at the end of both experiments, were significantly lower in substrate bags treated with either of the two acidic solutions. This research showed that treatments with acetic acid – and to a lesser extent hydrochloric acid solutions – can reduce the spread and severity of P. eryngii yellowing.  相似文献   
87.
为有效控制大樱桃流胶病的发生与危害,试验设计了7种不同药剂处理对大樱桃流胶病的防治效果进行评价。结果表明,在单剂中防效最好的是6%春雷霉素AS,2次防效调查结果分别为28.42%和50.20%,3%中生菌素WP与石硫合剂的防效也均超过30%,80%代森锰锌WP2次防效调查结果分别为22.02%和17.01%,有下降趋势。在复配混剂中,3%中生菌素WP与6%春雷霉素AS组合对流胶病防治效果最好,2次防效调查结果分别是42.22%和63.25%;其他2种处理防效较差,其中3%中生菌素WP和80%代森锰锌WP混用的防效仅达到10.75%和25.69%。  相似文献   
88.
Tree growth and health status appear to be related to foliar nutrient contents. Foliar nutrient concentration might be the result of a complex interaction between soil nutrients and effective availability caused by climate, water and other site and treatment effects. This study examines foliar macronutrient (N, P, K, Ca, Mg) and organic C concentrations in Aleppo pine (Pinus halepensis) needles (between 5 and 18 months old), as well as time course variability (nine dates, from July 1999 to November 2001). Variability was assessed depending on quality site (two sites, Yeste and Calasparra; SE Spain) and seven silvicultural treatments including thinning, scrubbing, pruning and particular combinations of them. Foliar macronutrient concentrations for Aleppo pine in South-eastern Spain were slightly lower (N, P, K,) or higher (Mg, Ca) than the considered as adequate ranges for Aleppo pine and Pinus genera. However, our results agree well with other normal ranges reported for Aleppo pine in Spain and for other North American Pinus species such as P. elliottii, P. taeda and P. palustris. Site, treatment and date (season) affected significantly the foliar macronutrient and C concentration, although the most important was the date, likely due to the two growth periods per year that Aleppo pine has in Mediterranean sites. Silvicultural treatments affected foliar nutrient concentration, so that the concentrations of N, P and K were higher when treatments included thinning than those that did not. The contrary was true for Mg and Ca. However, treatments did not affect the time course of the concentration, i.e., seasonality was not broken due to treatments. Moreover, the effect of the treatments was markedly high along the first year after they were applied but the differences were attenuate 2 years later. Site affected the time course of N, K, Mg and C in a different way: while for N, K and C, at the end of study period, they were higher in Calasparra than in Yeste, for Mg the contrary was true. Nutrient ratios had a different behaviour regarding to single nutrient: although date was significant, we did not appreciate seasonality. In addition, some nutrient ratios were not affected by treatments (N/P, N/K, Ca/Mg,) or by site (N/Ca, K/Ca). Average foliar N concentration and Ca/Mg ratio explained significantly the mean diameter and height growth, so that higher is the foliar N concentration and lower is Ca/Mg, higher is the growth.  相似文献   
89.
By afforestation trial, the adaptation and growing states of 5 Banksia robur provenances in Jianfengling of Hainan were studied, and the effects of provenance and fertilizer treatment on the survival rate, height and ground diameter were analyzed. The results showed that all the 5 provenances had a good adaptability in Hainan province. 2 months after planting, the survival rate was 85%, but it was easily affected by air humidity and became lower in the dry season, especially the provenance No.38164, showing that the B. robur needs wet environment. The study also found that different provenances and fertilizer treatments had significant impact and interactions on the growth of B. robur. The provenance No.38163 had the fastest grow speed, with 1.35 mm of ground diameter increment and 10.57 cm of height increment during 3 months, while the provenance No.38164 had the lowest grow speed. The provenance No.39163 also had a strong barren resistance, while the provenances No.38177 and No.38199 needed well water and nutrient conditions. Different fertilizer treatments could enlarge the difference in growth status of the provenances, and the composted cattle manure had the best effect on promoting growth status, which could be used as the best fertilizer in afforestation.  相似文献   
90.
Predispersal seed predation among individual Acacia macrostachya trees over two sites in Burkina Faso was assessed. In addition, the effects of seed predation on seed viability; germination responses to scarification (mechanical, hot water at 60, 70 and 80°C, and sulphuric acid for 10, 20 and 30 min) and dry heat (at 60, 70 and 80°C for 15, 30 and 60 min each) treatments were investigated under laboratory conditions. The results indicated a large difference in predation intensity among individual trees, as well as between sites. Predispersal predation significantly decreased seed germination, particularly when the number of insect larvae per seed increased. Scarified and unscarified seeds germinated equally well, except for hot water treatments of high temperature. This indicates lack of physical dormancy and dispersed seeds can readily germinate provided that conditions for germination are conducive. Seeds exposed to dry heat treatments also germinated close to 97% under low intensity and short exposure times. This suggests that fire, under natural condition, plays a key role in triggering germination of A. macrostachya seeds.  相似文献   
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