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951.
952.
邬春立 《四川畜牧兽医学院学报》2007,5(6):92-99
鲁迅的死亡意识既不同于西方现代的死亡意识,又迥异于传统文化中的死亡意识,具有强烈的现代个性色彩。他将死亡与新生、自我与历史、民族、传统紧密地统一在一个充满悖论的个体之内,并且上升到生存本体意义,因而具有宽广的视野和深邃的内蕴。 相似文献
953.
Fuensanta García‐Orenes Antonio Roldn Alicia Morugn‐Coronado Carlos Linares Artemi Cerd Fuensanta Caravaca 《Land Degradation \u0026amp; Development》2016,27(6):1622-1628
Soil microbial populations and their functions related to nutrient cycling contribute substantially to the regulation of soil fertility and the sustainability of agroecosystems. A field experiment was performed to assess the medium‐term effect of a mineral fertilizer and two organic fertilization systems with different nitrogen sources on the soil microbial community biomass, structure, and composition (phospholipid fatty acids, pattern, and abundance), microbial activity (basal respiration, dehydrogenase, protease, urease, β‐glucosidase, and total amount of phosphomonoesterase activities), and physical (aggregate stability) and chemical (total organic C, total N, available P and water‐soluble carbohydrates) properties in a vineyard under semiarid Mediterranean conditions after a period of 10 years. The three fertilization systems assayed were as follows: inorganic fertilization, addition of grapevine pruning with sheep manure (OPM), and addition of grapevine pruning with a legume cover crop (OPL). Both treatments, OPM and OPL, produced higher contents of total organic carbon, total N, available P, water‐soluble carbohydrates, and stable aggregates. The organic fertilization systems increased microbial biomass, shifted the structure and composition of the soil microbial community, and stimulated microbial activity, when compared with inorganic fertilization. The abundances of fungi and G+ bacteria were increased by treatments OPM and OPL, without significant differences between them. Organic and inorganic fertilization produced similar grapevine yields. The ability of the organic fertilization systems for promoting the sustainability and soil biological and chemical fertility of an agroecosystem under semiarid conditions was dependent of the organic N source. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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955.
Major sugar and carboxylic acid components in apricot flesh fruits were detected and quantified. Fifty-one genotypes including
clones growing in France, Spain, Italy, Greece and USA, belonging to the INRA germ plasm collection has been evaluated. Principal
component analysis (PCA) has been performed to study correlation among fruit quality measurements and to interpret relationships
between genotypes as a tool for germ plasm characterization. A marked variation in malic and citric acid content has been
observed and PCA revealed clusters of apricot genotypes for the malic/citric ratio content. A good correlation between sugar
component and refractometer index (r = 0.83) has been detected. The wide range of diversity in malic and citric acid content in apricot germ plasm makes it possible
to breed and select genotypes with improved flavour on the basis of superior phenotypes.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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不同施肥条件下夏玉米的干物质积累、产量及氮肥利用效率 总被引:24,自引:2,他引:24
针对我国华北地区夏玉米生产中所面临的氮素污染和秸秆资源严重浪费等问题,中国农业大学和德国霍恩海姆大学(Hohenheim University of Germany)自1999以来开展了中德国际合作项目“华北平原作物高产高生产力条件下环境可承受的持续农业研究”。研究表明:在同一时期,优化施肥、秸秆还田优化施肥与传统施肥夏玉米干物质积累量无显著性差异。拔节到吐丝,优化施肥的干物质日增长量和干物质积累量并不低于传统施肥,吐丝到灌浆,略低于传统施肥;秸秆还田优化施肥两阶段的干物质日增长量和干物质积累量最高。3处理间夏玉米产量无显著性差异。优化施肥和秸秆还田优化施肥条件下,氮肥当季利用率显著高于传统施肥。 相似文献
960.
A 4-year field study was carried out to determine dry matter and nitrogen accumulation until anthesis and at grain filling period and dry matter translocation and utilization in grain filling of barley. Twenty two-rowed spring barley (Hordeum vulgare ssp. distichum L.) cultivars originated from different countries (Yugoslavia, Germany, Australia, the Czeck Republic, Netherlands, France and USA) were grown during 1995–1998 on a non-calcareous chernozem soil near Novi Sad (45° 20′N, 15° 51′E, 86 m asl). Dry matter and nitrogen accumulation depended on the cultivar and year. In a year with favorable weather conditions, 58% of dry matter was accumulated during pre-anthesis, while in a year with less favorable weather the amount was 48%. In the favorable year 91% and in unfavorable year 65% of nitrogen was accumulated until anthesis. The results indicated that the greater amount of dry matter and nitrogen accumulated before anthesis. Dry matter translocation efficiency depended on the cultivar and ranged from 3 to 16.4%, while the contribution of pre-anthesis assimilates to kernel varied from 4 to 24.2%. Cultivars that have been developed for the growing conditions of the area where the experimental site was located, i.e. adapted ones, did not use pre-anthesis dry matter for grain filling. High positive correlations (P<0.01) were found between biomass at anthesis and biological yield, dry matter translocation efficiency, contribution of translocated dry matter to grain yield, and total plant nitrogen at maturity. Accumulated nitrogen at anthesis was positively correlated (P<0.01) with growing degree–days until anthesis, dry matter at anthesis and dry matter translocation parameters. Heritability for the investigated characters was rather high, over 0.60. 相似文献