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11.
Thirty-one meadows were investigated within five sites representing various farming styles found in Austrian cultural landscapes. The meadows were analysed regarding (a) biodiversity (vascular plant and bryophyte species richness), (b) land-use practices (fertiliser input, mowing intensity, the use of silage), and (c) economic aspects (variable costs, profit margin and subsidies per ha). There were significant negative correlations between plant species richness and mowing intensity and intensity of fertiliser application. Bryophytes were good indicators of low nutrient regimes, having high species richness at low fertiliser input. Vascular plants showed highest species richness at an intermediate nitrogen supply. The total plant species richness decreased with increasing nitrogen supply. Intensive silage production was also negatively correlated with plant diversity. Species with a very narrow ecological niche of soil moisture and nutrients declined, whereas species adapted to wider ecological conditions increased. Profit margin and variable costs correlated negatively with plant species richness, with meadows that offered low or no profit margins showing highest species richness. There was no significant relationship between species richness and the amount of subsidies invested at the study meadows. Estimated costs of maintaining a species are shown. It is concluded that if plant species richness are to be maintained in these meadows, farmers have to receive increased financial incentives through agro-environmental subsidies for appropriate meadow management, and these have to be linked to clearly defined measures.  相似文献   
12.
以奥地利黑麦(S eca le cerea le L.)为试验材料,通过G iem sa C-分带对其进行了细胞学鉴定、染色体核型与C-带分析。结果表明,奥地利黑麦体细胞染色体为14条,花粉母细胞减数分裂中期Ⅰ染色体形成7个二价体,其核型公式为2n=2x=14=10m+2sm+2m(SAT)。通过C-分带将奥地利黑麦1R~7R的7条染色体区分开来,其C-带带型公式为2n=14=2C+I+T+2C+T+4I+T+2C+I+T++2T+2ST。奥地利黑麦除2R和4R长臂近端部约1/4处有带且7R无中间带外,其余带型与黑麦标准C-分带带型基本一致。  相似文献   
13.
The considerable year‐to‐year and seasonal variation in grassland production is of major importance to dairy farmers in Europe, as production systems must allow for the risk of unfavourable weather conditions. A large portion of the variability is caused by weather and its interaction with soil conditions and grassland management. The present study takes advantage of the interactions between weather, soil conditions and grassland management to derive a reliable grassland statistical model (GRAM) for grasslands under various management regimes using polynomial regressions (GRAM‐R) and neural networks (GRAM‐N). The model performance was tested with a focus on predicting its capability during unusually dry or wet years using long‐term experimental data from Austrian sites. The GRAM model was then coupled with the Met&Roll stochastic weather generator to provide estimates of harvestable herbage dry matter (DM) production early in the season. It was found that, with the GRAM‐N or GRAM‐R methodology, up to 0·78 of the variability in harvested herbage DM production could be explained with a systematic bias of 1·1–2·3%. The models showed stable performance over subsets of dry and wet years. Generalized GRAM models were also successfully used to estimate daily herbage growth during the season, explaining between 0·63 and 0·91 of variability in individual cases. It was possible to issue a probabilistic forecast of the harvestable herbage DM production early in the season with reasonable accuracy. The overall results showed that the GRAM model could be used instead of (or in parallel with) more sophisticated grassland models in areas or sites where complete data sets are not yet available. As the model was tested under various climatic and soil conditions, it is suggested that the proposed approach could be used for comparable temperate grassland sites throughout Europe.  相似文献   
14.
Schmallenberg virus (SBV) has emerged in summer–autumn 2011 in north-western Europe. Since then, SBV has been continuously spreading over Europe, including Austria, where antibodies to SBV, as well as SBV genome, were first detected in autumn 2012. This study was performed to demonstrate the dynamics of SBV spread within Austria, after its probable first introduction in summer 2012. True seroprevalence estimates for cattle and small ruminates were calculated to demonstrate temporal and regional differences of infection. Furthermore, the probability of SBV genome detection in foetal tissues of aborted or stillborn cattle and small ruminants as well as in allantoic fluid samples from cows with early foetal losses was retrospectively assessed.  相似文献   
15.
Norway spruce has shown needle yellowing and defoliation symptoms on manysites of the Bohemian Forest in north central Austria since theearly 1980s. A forest amelioration experiment was set up toevaluate the response of spruce to magnesite based fertilizerswith different solubilities. Response variables were a crownvigor index, diameter growth, nutrient contents in needles,soil solution chemistry, and soil chemistry. Soil solution atfertilized plots showed an immediate response in base cationconcentrations, nitrate concentrations and pH-values.Fertilization increased the pool of exchangeable cations in theupper 15 cm of the soil and reduced levels of exchangeable Al. Themagnesium and calcium content of the needles of dominant trees wasgreatly improved. Fertilization has increased the mineralizationrate of soil organic matter. Diameter growth, as a measure of treevigor, showed a pronounced positive response with a time delay of5 years. Our results demonstratethat magnesite based fertilizers are a viable option to improvethe nutritional status of spruce forests on granitic bedrock.  相似文献   
16.
17.
In the first study of the Protura of a big city, six representative habitat types were sampled in Vienna, Austria. Twenty-five sites between the green belt and the city centre yielded 42 known species. Abundance, species number and diversity were highest in colline deciduous forests, with a maximum of 23 syntopic species in a Quercus pubescens stand. Acerella muscorum, all of the five Acerentomon spp. and 13 further species occurred exclusively in colline deciduous forests. The mediterranean Berberentulus berberus and six other species were recorded exclusively in parks or artificial habitats, suggesting anthropogenic transport. No Protura were found in garden and arable soils. Species density in the municipal area of Vienna (415 km2) is a function of the city's biogeographic situation on the border between the Alps and the Pannonian lowland as well as its diversity of seminatural habitats, and unintentional introduction.  相似文献   
18.
  • 1. The ecological status of floodplain areas along the Austrian section of the Danube was assessed by an approach based on dragonfly surveys. Although this river section contains a relatively high portion of the river‐type‐specific alluvial floodplain areas, most of them are influenced by river regulation and damming.
  • 2. A key element of the assessment procedure, which is oriented towards the new EC Water Framework Directive, is the Odonate Habitat Index.
  • 3. Classification of ecological status is based on the comparison between the status quo and reference conditions derived from a historical situation minimally influenced by human activities.
  • 4. Data from 408 sites from 14 investigation areas were used. Ten of the 14 areas were ranked in class II (‘good ecological status’) within the five‐tiered system, which is the level of ecological status targeted in the directive. One area corresponds to the reference condition (class I, ‘high ecological status’), and three areas do not meet the quality objective (class III, ‘moderate ecological status’). A total of 49 species were found along the whole section, which represents 82% of the river‐type‐specific reference list.
Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
19.
【目的】构建用于制备级分离及高效鉴定黑麦籽粒Waxy蛋白亚基的技术体系,为该亚基理化特性的分析、功能的发掘及Waxy种质的快速筛选等提供理论参考。【方法】设计特异引物从灌浆期间的奥地利黑麦籽粒cDNA中克隆获得Waxy,并进行体外表达;利用DuoFlow对籽粒蛋白提取物进行纯化,对峰值收集物、原核表达产物及其Ni柱纯化的重组Waxy蛋白进行SDS-PAGE分离,挖取蛋白条带进行MALDI-TOF质谱鉴定,结合经由基因序列所推导的氨基酸序列,确定回收产物的Waxy蛋白属性;在优化电泳条件的基础上构建针对Waxy蛋白的毛细管电泳体系;同时,利用部分黑麦品种对DuoFlow及CE体系的有效性进行验证。【结果】核苷酸序列分析表明,从奥地利黑麦cDNA中克隆获得一条覆盖Waxy全长的编码序列(GenBank登录号:KF559182),其理论编码产物约为60 kD;利用DuoFlow Q1阳离子交换柱,以低浓度Tris-Hcl(20 mmol•L-1 Tris-Hcl,pH 9.5)进行蛋白挂柱,高浓度NaCl(20 mmol•L-1 Tris+1 mol•L-1 NaCl,pH 9.5)进行蛋白洗脱,214 nm波长检测,实现了对籽粒Waxy蛋白的DuoFlow高效分离;纯化产物的SDS-PAGE条带大小、质谱鉴定肽段与黑麦、小麦Waxy蛋白序列相似性的统计结果表明,DuoFlow峰值回收产物具有黑麦Waxy亚基一致的特征序列,故属于Waxy蛋白;以DuoFlow纯化产物为标准样,以0.05 mmol•L-1硼砂+15%乙腈+1%SDS溶液(pH 9.5)为缓冲液,采用分离电压20 kV,温度25℃,检测波长214 nm,压力进样,0.5 psi×5 s,在11—12 min处获得峰值约12 mAU单一主峰,图形清晰,基线水平,从而构建了Waxy蛋白的CE鉴定体系,且籽粒Waxy蛋白提取物能直接用于对该亚基的检测;同时,利用黑麦品种对上述体系的验证结果表明,DuoFlow及CE体系适于对Waxy亚基的高效分离与通量检测。【结论】从奥地利栽培黑麦cDNA文库中克隆获得Waxy完整编码序列,构建了能特异分离黑麦籽粒Waxy蛋白的DuoFlow制备级纯化体系,并确立了黑麦籽粒Waxy亚基的毛细管快速鉴定体系。  相似文献   
20.
Seropositivity among pregnant woman in Austria has decreased from 48% to 50% at the end of the 1970s to 35% in recent years. Despite this decrease, knowledge of possible sources and risk factors for Toxoplasma infection remains important. We reviewed seroepidemiological studies that were undertaken to assess the roles of undercooked meat and oocysts in cat faeces as potential sources of infection in pregnant women. Improved management and hygiene in pig herds raised in confinement have resulted in less contact of pigs with cats and a decrease of infected pigs within one decade from 14% in 1982 to 0.9% in 1992. In Austrian wild boar populations, however, seroprevalences remained essentially unchanged during the same decade (18% in 1983 and 19% in 1990–1993). Austrian sheep and goats are usually kept on small farms where cats abound and are predominantly seropositive (66% in sheep and 69% in goats). The seroprevalence in cats has decreased from approximately 81% in 1987 to 59% in 1996; presumably because of cats’ increased consumption of processed food. Despite the decrease of infection in pregnant women via the cat‐to‐pig pathway, it may be offset by a recent concomitant increase in mutton consumption. Free‐ranging chickens are a good indicator of the prevalence of T. gondii oocysts in the soil because chickens are ground feeders. Antibodies to T. gondii, as evaluated by the modified agglutination test, were found in 36% of chickens from 12 Austrian ‘biofarms’. Because Austrians rarely consume raw pork, the fraction of human T. gondii infections associated with pig meat consumption is likely small. As meat consumption and lifestyle patterns change in Austria, the risk of human infection with T. gondii via different pathways needs re‐evaluation and targeted educational efforts to control transmission.  相似文献   
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