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951.
952.
不断升级的教科书事件是日本对中国的民族优越心理的再现。日本对中国的民族优越感起始于近代,在侵华期间和战后以一贯之,现在又有了新特点,不仅存在于国家关系上,更多地则集中于经济和文化领域。造成这种社会心理传统的原因是多方面的。 相似文献
953.
植物半胱氨酸合成酶复合体(SAT/OAS-TL)研究进展 总被引:1,自引:0,他引:1
综述了植物半胱氨酸的合成调节和半胱氨酸合成酶复合体的结构、调节机理及其植物转基因的研究进展。 相似文献
954.
Increasing human demands for Earth’s resources are hastening many environmental changes and creating a need to incorporate the routine monitoring of ecosystem functions into forest management.Under global change and anthropogenic disturbances,soil carbon (C) cycling in terrestrial ecosystems is undergoing substantial changes that result in the transformation between soil C sources and sinks.Therefore,the forest C budget requires an understanding of the underlying soil C dynamic under environment... 相似文献
955.
Luying Sun Fengbin Song Shengqun Liu Qingjun Cao Fulai Liu 《Archives of Agronomy and Soil Science》2013,59(14):1932-1943
ABSTRACTSustainable agricultural management practices have attracted increasing attention due to their significant roles in benefiting the functions and sustainability of agro-ecosystems. An integrated agricultural practice (IP) in a maize cropping system was developed by changing row spacing, adopting no-tillage and residue return in the Northeast China. A 12-year field study was carried out to evaluate the effect of IP and conventional practice (CP) on soil physical properties, microbial biomass and enzyme activity during the cropping season. The results showed that soil organic matter under IP was increased by 17.4, 9.88 and 6.69% in June, August and October, respectively, than CP. IP enhanced microbial biomass C (by 31.7, 25.1 and 30.4% in June, August and October) and activities of invertase, urease and phosphatase (by 27.2–38.0, 78.9–182 and 9.8–29.0%) compared to CP, possibly attributing to an increase in the soil microbial community. Furthermore, the soil pH, water content, nitrogen and phosphorus contents, microbial biomass and some specific enzyme activities varied with sampling time. It is concluded that IP improved soil quality and health by increasing organic matter content and microbial biomass and activity in maize field in Northeast China, suggesting that IP is a feasible management technology for sustainable agriculture. 相似文献
956.
Hideaki Hirai Katsutoshi Sakurai Kazutake Kyuma 《Soil Science and Plant Nutrition》2013,59(3):497-507
Abstract Properties of sesquioxides, clay mineralogical composition, and charge characteristics of Brown Forest soils developed under beech forests in the Kinki (Ohdaigahara) and the Tohoku District (Hakkoda) were studied with special reference to their pedogenetic processes. The Brown Forest soils in the Kinki District were characterized by the translocation of free Al, formation of Al and/or Fe-humus complexes throughout the profile, and the predominance of 2:1: 1-2:1 intergrade minerals in the subsurface horizons, whereas those in the Tohoku District were characterized by the formation of allophane and no remarkable translocation of free Al oxides. This difference in the pedogenetic processes under the same vegetation was reflected on the amounts of Al released from primary minerals in relation to the amounts of organic matter accumulated. Major distinctive characteristics included the values of the Alp/Alo, the Fep/Feo, the Alo/Ald ratios, the Sio content, and the STPT-ZPC and pH(H2O) values. Among these the values of the Alo/Ald ratio and/or the Sio content were found to be suitable indices for the differentiation of Brown Forest soils from Andisols in Japan In addition to the criteria used to define andic soil properties. 相似文献
957.
Kyoichi Kumada 《Soil Science and Plant Nutrition》2013,59(1):106-111
I. Absorption Spectra of Some Artificial Humic Acids It is a well known fact that numerous dark brown or black and amorphous substances cap be produced from organic compounds by purely chemical processes. Some of them are called artificial humic acids, and have been used as a model of soil humic acids by many workers. But it is doubtful whether such artificial humic acids are considered to be a model of soil humic acids, even if there can be found any similarities in their properties. However it may be an useful method for the study of humus formation to compare artificial humic acids with soil humic acids, and to make efforts to find a good model or to prepare artificial humic acids comparable to soil humic acids under laboratory conditions. For this purpose, first of all, the author prepared artificial humic acids from glucose, hydroquinone and lignin, and their absorption spectra were determined. 相似文献
958.
菌渣纤维素降解菌的筛选与鉴定 总被引:6,自引:2,他引:4
为了寻找高效纤维素降解菌,提高菌渣堆肥微生物发酵效果,促进菌渣高效循环利用,从不同地点堆放的杏鲍菇菌渣中采集样品,利用羧甲基纤维素钠培养基分离纤维素降解菌,结合纤维素刚果红水解圈测定、滤纸条降解试验和纤维素酶(滤纸酶FPA、内切葡聚糖酶CMCase、外切葡聚糖酶C1、葡萄糖苷酶β-Gase)活性测定,筛选到4株(FB7、CB1、BC11、BC12)具有高效纤维素降解能力的细菌,经16S rDNA序列分析,鉴定FB7、CB1为枯草芽孢杆菌,BC11为链霉菌属Streptomyces albus,BC12是丛毛单胞菌属的Comamonas_jiangduensis,其中FB7降解能力强,可将滤纸条降解成糊状(10 d),纤维素酶活力很高,摇瓶发酵4 d后FPA、CMCase、C1酶、β-Gase的酶活分别为22.81、314.50、2.78、188.09 U·g-1。复合菌剂CB1+BC11+FB7的FPA、CMCase、C1酶、β-Gase的酶活高于其他各组合,为31.56、133.63、2.31、217.21 U·g-1,与FB7相比分别提高了38.4%、11.2%、178%、70.3%,将复合菌CB1+BC11+FB7接种到菌渣堆肥中,与对照相比,能快速提高堆体温度,且在翻堆后能更好地维持堆温。 相似文献
959.
乡村环境保护和管理的景观途径 总被引:2,自引:1,他引:1
恢复和提高生态服务功能已经成为区域可持续发展的重要途径.论文介绍了景观方法,探讨了乡村环境保护和管理景观方法途径,包括绿色基础设施建设、生态服务功能提升、农业生态系统生物关系重建、乡村景观特征提升、小流域面源污染控制景观综合管理以及构建以农户为主体的生态景观管护制度.结合海淀区土地整治绿色基础设施规划、北京市都市型现代农业万亩示范区生态景观建设规划设计案例,分析了乡村环境保护和管理需要从田块尺度提升到景观尺度的必要性,需要从区域生态景观战略规划、景观尺度上空间格局规划、生态景观化工程技术应用3个层次上,提高生态景观服务功能,保护和修复乡村生态环境.在项目实施过程中,要加强不同的土地经营者、管理者以及利益相关者合作,推进综合景观管理. 相似文献
960.
旨在杆状病毒系统中表达TIMMDC1/c3orf1(Translocase of inner mitochondrial membrane domain containing l)基因,为其应用和功能研究奠定基础.将TIMMDC1基因克隆至重组杆状病毒表达系统的载体中,构建重组穿梭质粒,转染Bm-N细胞,Western blotting验证蛋白的表达.结果表明,重组克隆质粒pFastBac 1-GFP-TIMMDC1的两两酶切结果证实重组克隆质粒构建正确.PCR结果显示重组穿梭质粒Bacmid pFastBac1+ TIMMDC1+GFP可扩增出目的条带.Bm-N-rBacTIMMDC1的表达产物经Westem blotting分析,分别可见相对分子质量57kD的特异蛋白条带,表明融合蛋白TIMMDC1 +GFP在家蚕Bm细胞中成功的进行了表达.本研究成功在杆状病毒表达系统中表达了TIMMDC1基因,为其临床应用和功能研究奠定了基础. 相似文献