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“绿量”到“绿质”:广州市空港经济区绿化景观规划探索 被引量:3
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作者 范京 胡峰 +1 位作者 姚睿 林晨薇 《规划师》 北大核心 2020年第9期57-63,共7页
文章通过对当前基于"绿量"管控的绿化景观规划进行总结与反思,指出城市重点片区的绿化景观规划应改变"绿量"导向的编制思路,转向以塑造高品"绿质"为目标,以绿化功能和属性管控为重点。同时,结合广州市空... 文章通过对当前基于"绿量"管控的绿化景观规划进行总结与反思,指出城市重点片区的绿化景观规划应改变"绿量"导向的编制思路,转向以塑造高品"绿质"为目标,以绿化功能和属性管控为重点。同时,结合广州市空港经济区绿化景观规划实践,从理念、技术和成果三方面切入,探索更多元的绿化景观体系,构建"功能化-品质化-特色化"三化标准指标体系,以"图则+清单+手册"的形式实现对绿化的分级分类管控和全覆盖指引,力求实现从"绿量"到"绿质"的精细化转变。 展开更多
关键词 绿化景观 “绿量” “绿质” 城市重点片区
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Heterogeneity of Chlorophyll Fluorescence of Phyllostachys edulis cv.Pachyloen Leaves 被引量:1
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作者 牟少华 郭起荣 +1 位作者 王真 冯云 《Agricultural Science & Technology》 CAS 2012年第12期2511-2513,2537,共4页
[Objective] This study aimed to explore the heterogeneity of chlorophyll flu- orescence of Phyllostachys edulis cv. Pachyloen leaves. [Method] Using the chloro- phyll fluorescence system and fluorescence imaging syste... [Objective] This study aimed to explore the heterogeneity of chlorophyll flu- orescence of Phyllostachys edulis cv. Pachyloen leaves. [Method] Using the chloro- phyll fluorescence system and fluorescence imaging system in the Mini-IMAGING- PAM, the chlorophyll fluorescence of Phyllostachys edulis cv. Pachyloen leaves were measured and the fluorescence parameters were calculated. [Result] The homo- geneities of the maximal quantum yield of PS II (Fv/Fm) and the leaf absorptivity (Abs) were higher, with CVs (Coefficient of Variation) of 1.58%-1.68% and 1.75%- 2.12% respectively, while the heterogeneities of the actual quantum yield (Y), non- photochemical quenching (NPQ/4), photochemical quenching(qP) and relative photo- synthetic rate (PS/50) were higher, with CVs of 9.60%-14.23%, 10.23%-13.02%, 11.92%-13.02% and 11.15%-17.74% respectively. The trends of heterogeneity change in Y, qP and PSI50 were basically the same with transversely higher het- erogeneity at two sides and lower heterogeneity in the middle, namely with larger CVs at the edges of leaves and smaller ones around the midrib. Longitudinally, the coefficients of variation of Y, qP and PS/50 decreased gradually (from top to bot- tom), which indicated that the heterogeneity declined from the leaf tip to the base. The trends of heterogeneity change in PS/50 and NPQ/4 were opposite. [Conclusion] The fluorescence parameters of Phyllostachys edulis cv. Pachyloen leaves revealed different heterogeneity. 展开更多
关键词 Phyllostachys edulis cv. Pachyloen CHLOROPHYLL FLUORESCENCE HETEROGENEITY
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Antialgal Activities of Allelochemical Extracts from 3 Terrestrial Plant Species 被引量:8
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作者 缪莉 董昆明 +3 位作者 李楠 周晓见 靳翠丽 封克 《Agricultural Science & Technology》 CAS 2010年第7期20-24,28,共6页
[Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.[Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora jap... [Objective] The aim was to study the antialgal activities of allelochemical extracts from three terrestrial plant species.[Method] The allelochemicals were extracted from the leaves of Magnolia grandiflora,Sophora japonica f.pendula and Buxus sinica (Rehd.et Wils.) Cheng by alcohol extraction,n-hexane,ethyl acetate and n-utanol phase.Furthermore antialgal activities of all components were determined.[Result] The active substances of M.grandiflora mainly existed in n-hexane and n-butanol phases.The active substances of S.japonica mainly existed in n-hexane phase,while the active substances of B.sinica mainly existed in ethyl acetate and aqueous phase.All the active substances showed significant antialgal activity (50% inhibition) after culture for 1 d except aqueous phase of B.sinica.In addition,inhibition rates of the tested phases increased with the increasing of culture duration and testing concentrations.The inhibition rates were over 90% against the growth of M.aeruginosa after culture for 7 d.The n-hexane and n-butanol phases of M.grandiflora exhibited the best antialgal activity,over 96% inhibition rate at the concentration of 25 μg/ml,which was significantly higher than those of the other components,furthermore it could cause shrinkage and obvious surface inanition of Microcystis aeruginosa.[Conclusion] The n-hexane and n-butanol phases of M.grandiflora have the best inhibition activities on the growth of Microcystis aeruginosa,so they are worthy of further study. 展开更多
关键词 ALLELOCHEMICALS Antialgal activity Microcystis aeruginosa Water bloom defense
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Mixed Substrate Soilless Cultivation Techniques for Mini Watermelon in Spring Greenhouse of Beijing Area 被引量:2
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作者 马超 曾剑波 +4 位作者 朱莉 陈艳利 李云飞 李婷 攸学松 《Agricultural Science & Technology》 CAS 2017年第12期2282-2285,共4页
Watermelon, as a traditional dominant crop in Beijing, has obvious indus- trial advantages. The mixed substrate soilless cultivation techniques developed by the Beijing Agricultural Technology Extension Station for mi... Watermelon, as a traditional dominant crop in Beijing, has obvious indus- trial advantages. The mixed substrate soilless cultivation techniques developed by the Beijing Agricultural Technology Extension Station for mini watermelon in spring greenhouse can effectively solve the problem of continuous cropping in facility wa- termelon, and they are conducive to green, safe and efficient development of water- melon industry for fixed nutrient solution formula, automatic water and fertilizer irri- gation, stable product quality and facilitating large-scale and standardized production. 展开更多
关键词 Facility watermelon Mixed matrix Soilless cultivation Green and safe
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cpSSR: a New Tool to Analyze Chloroplast Genome of Citrus Somatic Hybrids 被引量:8
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作者 程运江 郭文武 邓秀新 《Acta Botanica Sinica》 CSCD 2003年第8期906-909,共4页
Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs ... Chloroplast simple sequence repeat (cpSSR) markers in Citrus were developed and successfully used to analyze chloroplast genome inheritance of Citrus somatic hybrids. Twenty-two previously reported cpSSR primer pairs from pine (Pinus thunbergii Parl.), rice (Otyza sativa L.) and tobacco (Nicotiana tabacum L.) were tested in Citrus, nine of which could amplify intensive PCR products by agarose gel electrophoresis. Chloroplast genome inheritance of Citrus somatic hybrids from nine fusions was then analyzed, and five of the nine pre-screened primer pairs showed polymorphisms by polyacrylamide gel electrophoresis. The results revealed the random inheritance nature of chloroplast genome in all analyzed Citrus somatic hybrids, which was in agreement with previous reports based on RFLP or CAPS analyses. It was also shown that cpSSR is a more efficient tool in chloroplast genome analyses of somatic hybrids in higher plants, compared with the conventional RFLP or CAPS analyses. 展开更多
关键词 Citrus somatic hybrids MICROSATELLITE simple sequence repeat (SSR) chloroplast genome
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Effects of Tobacco Plastid Division Genes NtFtsZ1 and NtFtsZ2 on the Division and Morphology of Chloroplasts 被引量:5
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作者 王东 孔冬冬 +3 位作者 鞠传丽 胡勇 何奕昆 孙敬三 《Acta Botanica Sinica》 CSCD 2002年第7期838-844,共7页
As an important group of plant cellular organelles, the molecular mechanism of plastid division is poorly understood. Recent studies have revealed that the homologs of ftsZ gene, an essential prokaryotic cell division... As an important group of plant cellular organelles, the molecular mechanism of plastid division is poorly understood. Recent studies have revealed that the homologs of ftsZ gene, an essential prokaryotic cell division gene, are involved in plastid division process of plant cells. Antisense and sense expression constructions were employed to investigate the functions of the two ftsZ genes, NtFtsZ1 and NtFtsZ2, in transgenic Nicotiana tabacum L. plants. Although antisense expression of,NtFtsZs reduced the native protein level obviously, the size and number of chloroplasts in transgenic tobacco plants had no effect. In contrast, overexpression of NtFtsZs in transgenic plants strikingly changed the number and morphology of chloroplasts. Even only 1 - 2 huge chloroplasts could be seen in the mesophyll cells of some overexpression transgenic plants. Analyses of chloroplast ultrastructures and chlorophyll content of different transgenic plants suggested that NtFtsZs gene have no direct influence on the normal development and function of chloroplasts. ne changes in chloroplast morphology must be a compensation for the change in chloroplast number. The different phenotypes of chloroplasts in antisense and sense transgenic plants implied that different members from the same ftsZ gene family may have similar function in controlling plastid division. Meanwhile, the changes of chloroplast morphology in sense transgenic plants represented the possible plastoskeleton function of ftsZ in higher plant. 展开更多
关键词 Nicotiana tabacum ftsZ gene plastid division plastid morphology plastoskeleton
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Effects of Water Stress on Stay Green of Sugarcane Innovative Materials Yunge F_2 Generation
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作者 经艳芬 俞华先 +8 位作者 桃联安 周清明 董立华 郎荣斌 边芯 孙有芳 安汝东 朱建荣 冯蔚 《Agricultural Science & Technology》 CAS 2016年第11期2462-2468,共7页
[Objective] This study aimed to investigate the effect of water stress on stay green of Yunge F2 generation. [Method] Total 26 sugarcane innovative germplasm materials of Yunge F2 generation, along with their female p... [Objective] This study aimed to investigate the effect of water stress on stay green of Yunge F2 generation. [Method] Total 26 sugarcane innovative germplasm materials of Yunge F2 generation, along with their female parent, were selected as the experimental materials. Based on the observation on appearance of stray green and other five physiological and biochemical indexes, the drought resis- tance of the experimental materials was evaluated comprehensively by subordinate function method, grey relational analysis, and cluster analysis. [Result] The rank of drought resistance of the experimental materials was not exactly the same between subordinate function method and grey relational analysis. However, the drought .re- sistance evaluation results by isometric range-based cluster analysis were consistent with those by the two foregoing methods except Yunge F2 11-68 and Yunge F1 11- 254. At the Euclidean distance of 2.00, the tested materials were classified into four groups. The first group included 8 drought-strongly resistant materials, the third group included 6 drought-moderately resistant materials, the fourth group included 3 drought-poorly resistant materials, and the second group included drought-strongly resistant and drought-moderately resistant materials. The drought resistance coeffi- cients of green leaf numberLtotal leaf number and top four leaves chlorophyll content showed significantly positive correlation with drought resistance comprehensive eval- uation value, thus green leaf number/total leaf number and top four leaves chloro- phyll content could be used as the evaluation indexes of drought resistance in sug- arcane. [Conclusion] The excellent materials possess strong drought resistance and good green holding performance, such as Yunge F2 11-159, can be used as crucial parents and basic germplasm materials in drought resistance breeding of sugarcane. 7 展开更多
关键词 Water stress SUGARCANE Innovative germplasm Stay green
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Chloroplast Genetic Engineering in Higher Plants 被引量:1
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作者 张景昱 张嫄 宋艳茹 《Acta Botanica Sinica》 CSCD 2003年第5期509-516,共8页
Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plasti... Chloroplast genetic engineering, with several advantages over nuclear genetic engineering, is now regarded as an attractive new technology in basic and applied research, including deepening our understanding of plastid genome, engineering plant metabolic system, generating transplastomic plants with higher resistance to insect, disease, drought and herbicide and bioproducing of antibodies and vaccines. In this review, the principle and operating system for chloroplast genetic engineering and its application in higher plants have been discussed. 展开更多
关键词 chloroplast genetic engineering transplastomic plants plastid genome
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Localization of Two GFP_tagged Tobacco Plastid Division Protein NtFtsZs in Escherichia coli 被引量:1
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作者 王东 孔冬冬 +3 位作者 鞠传丽 胡勇 何奕昆 孙敬三 《Acta Botanica Sinica》 CSCD 2002年第8期931-935,共5页
Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli . The regular localizations of full length NtFtsZs∶GFP along the fil... Two plastid division genes, NtFtsZ1 and NtFtsZ2 isolated from Nicotiana tabacum L. were fused with gfp and expressed in Escherichia coli . The regular localizations of full length NtFtsZs∶GFP along the filamentous bacteria indicated that the NtFtsZs could recognize the potential division sites in E. coli and be polymerized with heterogeneous FtsZ from bacteria. The overexpression of NtFtsZs ∶ gfp inhibited the division of host strain cells and resulted in the long filamentous bacterial morphology. These results suggested that eukaryotic ftsZs have similar function to their prokaryotic homologs. Meanwhile, the different deletions of motifs of NtFtsZs are also employed to investigate the functions of these proteins in E. coli . The results showed that the C_terminal domains of NtFtsZs were related to the correct localization of NtFtsZs in E. coli and the N_terminal domains of NtFtsZs were responsible for the polymerization of homogeneous and heterogeneous FtsZ proteins. The significance of these results in understanding the functions of NtFtsZs in plastid division were discussed. 展开更多
关键词 Nicotiana tabacum plastid division gene NtFtsZ GFP localization in Escherichia coli
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Efficient Green Modern Agriculture of Fenlong Cultivation and Its Application Prospects 被引量:1
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作者 韦本辉 《Agricultural Science & Technology》 CAS 2017年第12期2658-2663,2666,共7页
Based on the evolution of farming revolution in Fengyan aiming to create a healthier and more beautiful human existence and a harmonious coexistence with nature, this study introduced Fenlong green agriculture, which ... Based on the evolution of farming revolution in Fengyan aiming to create a healthier and more beautiful human existence and a harmonious coexistence with nature, this study introduced Fenlong green agriculture, which had the characteristics of natural yield increase of more than 10% with zero fertilization, and yield increase of 10%-30%, quality improvement of 5% and doubled land water holding capacity with the conventional fertilization in over 20 crops in more than 20 provinces, and significant reforming efficiency on salinized land and grassland; for the first time made a comprehensive description of high efficient application of Fenlong green modern agriculture to explore natural resources, realizing the sustainable develop- ment of quality improvement, yield increase and efficiency enhancement; for the first time clarified the scientific basis and theoretical system of the green efficient mod- ern agricultural technique-Fenlong cultivation, as well as the basic connotations and concepts of Fenlong cultivation, green efficient modern agricultural technical system; created a new model of efficient modern agricultural production and new technology system, and 6 major technical projects like cultivated land improvement to increase yield and transformation of salinized land and grassland, which could play a role in relieving the climatic disasters like haze, transformation of farmland with medium to low yield as well as the construction of high standard farmland, sucrose industry and "One Road One Belt" strategy; for the first time proposed Fenlong cultivation as the "China technology card" in China and even the whole world, so as to make people understand the particular significance of this technology to green develop- ment, which could benefit the future generations. 展开更多
关键词 Fenlong Green high-efficient modern agriculture Yield increase andquality improvement Scientific significance Application prospect
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Research Progress of Quality Characteristics and Comprehensive Utilization of Mung Beans 被引量:5
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作者 Qian TIAN Wenlan ZHANG +5 位作者 Qun LI Tingjin YAN Nana LI Shuang DAI Yanyan PU Hanfeng DING 《Agricultural Science & Technology》 CAS 2017年第1期127-133,136,共8页
Mung bean is one of the major legume crops in China, and its nutritional quality and processing quality directly affect the development of mung bean processing industry. In order to promote the development of mung bea... Mung bean is one of the major legume crops in China, and its nutritional quality and processing quality directly affect the development of mung bean processing industry. In order to promote the development of mung bean processing industry, the research progress of mung bean quality characteristics, including physical quality, nutritional quality, medicinal value and the processing quality, were summarized based on literatures both at home and abroad, and the current exploitation status of starch, protein, dietary fiber, resistant starch, flavonoids and superoxide dismutase of mung bean was also reviewed. In order to promote the development of mung bean processing industry, it should strengthen the research on quality characteristics and functional ingredients of mung bean, pay attention to the development of healthy products, improve the processing technology, and cultivate a group of leading mung bean processing companies with strong competence in the market. 展开更多
关键词 Mung bean Quality characteristics Comprehensive utilization
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Construction of a chloroplast protein interaction network and functional mining of photosynthetic proteins in Arabidopsis thaliana 被引量:4
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作者 Qing-Bo Yu Guang Li +13 位作者 Guan Wang Jing-Chun Sun Peng-Cheng Wang Chen Wang Hua-Ling Mi Wei-Min Ma Jian Cui Yong-Lan Cui Kang Chong Yi-Xue Li Yu-Hua Li Zhongming Zhao Tie-LiuShi Zhong-Nan Yang 《Cell Research》 SCIE CAS CSCD 2008年第10期1007-1019,共13页
Chloroplast is a typical plant cell organelle where photosynthesis takes place. In this study, a total of 1 808 chloroplast core proteins in Arabidopsis thaliana were reliably identified by combining the results of pr... Chloroplast is a typical plant cell organelle where photosynthesis takes place. In this study, a total of 1 808 chloroplast core proteins in Arabidopsis thaliana were reliably identified by combining the results of previously published studies and our own predictions. We then constructed a chloroplast protein interaction network primarily based on these core protein interactions. The network had 22 925 protein interaction pairs which involved 2 214 proteins. A total of 160 previously uncharacterized proteins were annotated in this network. The subunits of the photosynthetic complexes were modularized, and the functional relationships among photosystem Ⅰ (PSI), photosystem Ⅱ (PSII), light harvesting complex of photosystem Ⅰ (LHC Ⅰ) and light harvesting complex of photosystem Ⅰ (LHC Ⅱ) could be deduced from the predicted protein interactions in this network. We further confirmed an interaction between an unknown protein AT1G52220 and a photosynthetic subunit PSI-D2 by yeast two-hybrid analysis. Our chloroplast protein interaction network should be useful for functional mining of photosynthetic proteins and investigation of chloroplast-related functions at the systems biology level in Arabidopsis. 展开更多
关键词 ARABIDOPSIS chloroplast protein network functional linkage PHOTOSYNTHESIS
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Cloning and characterization of a glucose 6-phosphate/phosphate translocator from Oryza sativa 被引量:3
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作者 姜华武 佃蔚敏 +1 位作者 刘非燕 吴平 《Journal of Zhejiang University Science》 CSCD 2003年第3期331-335,共5页
Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 ph... Plastids of nongreen tissues import carbon as a source of biosynthetic pathways and energy, and glucose 6 phosphate is the preferred hexose phosphate taken up by nongreen plastids. A cDNA clone encoding glucose 6 phosphate/phosphate translocator ( GPT ) was isolated from a cDNA library of immature seeds of rice and named as OsGPT . The cDNA has one uninterrupted open reading frame encoding a 42 kDa polypeptide possessing transit peptide consisting of 70 amino acid residues. The OsGPT gene maps on chromosome 8 of rice and is linked to the quantitative trait locus for 1000 grain weight. The expression of OsGPT is mainly restricted to heterotrophic tissues. These results suggest that glucose 6 phosphate imported via GPT can be used for starch biosynthesis in rice nongreen plastids. 展开更多
关键词 Glucose 6 phosphate/phosphate translocator Starch synthesis Rice ( Oryza sativa L.)
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Science Letters:A modified chlorophyll absorption continuum index for chlorophyll estimation 被引量:3
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作者 YANG Xiao-hua HUANG Jing-feng +3 位作者 WANG Fu-min WANG Xiu-zhen YI Qiu-xiang WANG Yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2002-2006,共5页
There is increasing interest in using hyperspectral data for quantitative characterization of vegetation in spatial and temporal scopes. Many spectral indices are being developed to improve vegetation sensitivity by m... There is increasing interest in using hyperspectral data for quantitative characterization of vegetation in spatial and temporal scopes. Many spectral indices are being developed to improve vegetation sensitivity by minimizing the background influence. The chlorophyll absorption continuum index (CACI) is such a measure to calculate the spectral continuum on which the analyses are based on the area of the troughs spanned by the spectral continuum. However, different values of CACI were obtained in this method because different positions of continuums were determined by different users. Furthermore, the sensitivity of CACI to agronomic parameters such as green leaf chlorophyll density (GLCD) has been reduced because the fixed positions of con- tinuums are determined when the red edge shifted with the change in GLCD. A modified chlorophyll absorption continuum index (MCACI) is presented in this article. The red edge inflection point (REIP) replaces the maximum reflectance point (MRP) in near-infrared (NIR) shoulder on the CACI continuum. This MCACI has been proved to increase the sensitivity and predictive power of GLCD. 展开更多
关键词 CONTINUUM CHLOROPHYLL Sensitivity Prediction power
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Ionic Liquids: Progress and Prospective 被引量:2
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作者 孙宏伟 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第6期830-834,共5页
Ionic liquids (ILs) are green solvents that have attracted great attention in recent years due to their unique properties. In this paper the latest progresses in both the fundamental studies and applications of ILs ... Ionic liquids (ILs) are green solvents that have attracted great attention in recent years due to their unique properties. In this paper the latest progresses in both the fundamental studies and applications of ILs have been summarized, with the emphasis on the topics of physical properties, catalytic reactions, and biochemical engineering. The critical problems in the applications of the ILs have been addresses, and the prospective of the ILs were finally predicted. 展开更多
关键词 ionic liquids green solvents PROPERTIES APPLICATIONS REVIEW
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ROLE OF OUTER MEMBRANE PROTEINS IN IMIPENEM DIFFUSION IN PSEUDOMONAS AERUGINOSA 被引量:2
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作者 左联 姚天爵 《Chinese Medical Sciences Journal》 CAS CSCD 1999年第1期57-60,共4页
The present study identified the properties of porins in the outer membrane in Pseudomonas aeruginosa,and showed the role of outer membrane in determining imipenem diffusion in Pseudomonas a... The present study identified the properties of porins in the outer membrane in Pseudomonas aeruginosa,and showed the role of outer membrane in determining imipenem diffusion in Pseudomonas aeruginosa The molecular weight of the major outer membrane protein was analyzed by SDS PAGE The purification of the porins in Pseudomonas aeruginosa was achieved by DEAE ion exchange HPLC The purified outer membrane proteins were reconstituted with phosphatidylcholine and dicetylphosphate into membrane vesicles, and were tested by the liposomes swelling method for the diffusion of imipenem The permeability assay showed that OprC (70 kD), OprD 2 (46kD), and OprE(43 kD) were the channel forming proteins But only OprD 2 was thought to be the likely route of imipenem diffusion 展开更多
关键词 Pseudomonas aeruginosa outer membrane imipenem
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Effect of Slash Burning on Nutrient Removal and Soil Fertility in Chinese Fir and Evergreen Broadleaved Forests of Mid-Subtropical China 被引量:19
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作者 YANG YUSHENG, GUO JIANFEN, CHEN GUANGSHUI, HE ZONGMING and XIE JINSHENGFujian Agriculture and Forestry University, Nanping 353001 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第1期87-96,共10页
A Chinese fir forest (Cunninghamia lanceolata, CF) and an evergreen broadleaved forest (EB) located inFujian Province, southeastern China, were examined following slash burning to compare nutrient capital andtopsoil p... A Chinese fir forest (Cunninghamia lanceolata, CF) and an evergreen broadleaved forest (EB) located inFujian Province, southeastern China, were examined following slash burning to compare nutrient capital andtopsoil properties with pre-burn levels. After fire, nutrient (N, P and K) removal from burning residues wasestimated at 302.5 kg ha-1 in the CF and 644.8 kg ha-1 in the EB. Fire reduced the topsoil capitals of totalN and P by about 20% and 10%, respectively, in both forests, while K capital was increased in the topsoils ofboth forests following fire. Total site nutrient loss through surface erosion was 28.4 kg (N) ha-1, 8.4 kg (P)ha-1 and 328.7 kg (K) ha-1 in the CF. In the EB, the losses of total N, P and K were 58.5, 10.5 and 396.3kg ha-1, respectively. Improvement of soil structure and increase in mineralization of nutrients associatedwith increased microbe number and enzyme activities and elevated soil respiration occurred 5 days after fire.However, organic matter and available nutrient contents and most of other soil parameters declined one yearafter fire on the burned CF and EB topsoils. These results suggest that short-term site productivity canbe stimulated immediately, but reduced subsequently by soil and water losses, especially in South China,where high-intensity precipitation, steep slopes and fragile soil can be expected. Therefore, the silviculturalmeasurements should be developed in plantation management. 展开更多
关键词 chinese fir evergreen broadleaved forest nutrient removal slashburning soil fertility
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Effect of Two Herbicides on the Growth of Early Seedlings of Rye(Secale cereale) 被引量:2
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作者 党晨 高越 《Agricultural Science & Technology》 CAS 2011年第8期1213-1216,共4页
[Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye(Secale cereale).[Method]Effect of two kinds of herbicide(Atrazine and APM)on seedling growth of rye was investigated ... [Objective]The aim was to study the effect of herbicide on the growth of early seedlings of rye(Secale cereale).[Method]Effect of two kinds of herbicide(Atrazine and APM)on seedling growth of rye was investigated at the physiological,biochemical and cellular level.[Result]The Atrazin significantly decreased the contents of chlorophyll a,b and soluble proteins.Rye seeds were treated with 0.01-1 mg/L Atrazine for 16 h,the contents of chlorophyll a and b decreased from 1.26(a),0.49(b)mg/g FW(control)to 1.15(a),0.46(b)mg/g FW(0.1 mg/L)and 0.81(a),0.33(b)mg/g FW(1.0 mg/L).The content of soluble protein decreased with the increasing concentration of Atrazin.Atrazin had no significant influence on the cell division and chromosome structure variation.The contents of chlorophyll a,b and soluble proteins had no significantly change under the treatment of APM,but the number of chromosome structure variation such as chromosome bridge,multipolar division cells,lagging chromosome and unequal division cells increased significantly.[Conclusion]The critical concentration of Atrazine was 0.1-1.0 mg/L and 4 mg/L of APM in rye. 展开更多
关键词 HERBICIDES Secale cereal Chlorophyll content Soluble protein Chromosome structure variation
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Efficient expression of green fluorescent protein (GFP) mediated by a chimeric promoter in Chlamydomonas reinhardtii 被引量:3
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作者 吴锦霞 胡章立 +2 位作者 王潮岗 黎双飞 雷安平 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第3期242-247,共6页
To improve the expression efficiency of exogenous genes in Chlamydomonas reinhardtii, a high efficient expression vector was constructed. Green fluorescent protein (GFP) was expressed in C. reinhardtii under the con... To improve the expression efficiency of exogenous genes in Chlamydomonas reinhardtii, a high efficient expression vector was constructed. Green fluorescent protein (GFP) was expressed in C. reinhardtii under the control of promoters: RBCS2 and HSP70A-RBCS2. Efficiency of transformation and expression were compared between two transgenic algae: RBCS2 mediated strain Tran-Ⅰ and HSP70A-RBCS2 mediated strain Tran-Ⅱ. Results show that HSP70A-RBCS2 could improve greatly the transformation efficiency by approximately eightfold of RBCS2, and the expression efficiency of GFP in Tran-Ⅱ was at least double of that in Tran-Ⅰ. In addition, a threefold increase of GFP in Tran-Ⅱ was induced by heat shock at 40℃. All of the results demonstrated that HSP70A-RBCS2 was more efficient than RBCS2 in expressing exogenous gene in C. reinhardtii. 展开更多
关键词 expression efficiency green fluorescent protein (GFP) HSP70A-RBCS2 RBCS2 transformation efficiency
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Analysis on n-gram statistics and linguistic features of whole genome protein sequences
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作者 董启文 王晓龙 林磊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第5期694-698,共5页
To obtain the statistical sequence analysis on a large number of genomic and proteomic sequences available for different organisms, the n-grams of whole genome protein sequences from 20 organisms were extracted. Their... To obtain the statistical sequence analysis on a large number of genomic and proteomic sequences available for different organisms, the n-grams of whole genome protein sequences from 20 organisms were extracted. Their linguistic features were analyzed by two tests: Zipf power law and Shannon entropy, developed for analysis of natural languages and symbolic sequences. The natural genome proteins and the artificial genome proteins were compared with each other and some statistical features of n-grams were discovered. The results show that: the n-grams of whole genome protein sequences approximately follow the Zipf law when n is larger than 4; the Shannon n-gram entropy of natural genome proteins is lower than that of artificial proteins; a simple uni-gram model can distinguish different organisms; there exist organism-specific usages of "phrases" in protein sequences. It is suggested that further detailed analysis on n-gram of whole genome protein sequences will result in a powerful model for mapping the relationship of protein sequence, structure and function. 展开更多
关键词 n-gram statistics protein sequence Zipf law
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