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TBtools: An Integrative Toolkit Developed for Interactive Analyses of Big Biological Data 被引量:1148
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作者 Chengjie Chen Hao Chen +4 位作者 Yi Zhang Hannah R.Thomas Margaret H.Frank Yehua He Rui Xia 《Molecular Plant》 SCIE CAS CSCD 2020年第8期1194-1202,共9页
The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challen... The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challenging and time-consuming for most wet-lab biologists.Here,we present TBtools(a Toolkit for Biologists integrating various biological data-handling tools),a stand-alone software with a userfriendly interface.The toolkit incorporates over 130 functions,which are designed to meet the increasing demand for big-data analyses,ranging from bulk sequence processing to interactive data visualization.A wide variety of graphs can be prepared in TBtools using a new plotting engine("JIGplot")developed to maximize their interactive ability;this engine allows quick point-and-click modification of almost every graphic feature.TBtools is platform-independent software that can be run under all operating systems with Java Runtime Environment 1.6 or newer.It is freely available to non-commercial users at https://github.com/CJ-Chen/TBtools/releases. 展开更多
关键词 TBtools BIOINFORMATICS big data data visulization gene family
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Resource diversity of Chinese macrofungi:edible,medicinal and poisonous species 被引量:238
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作者 Fang Wu Li-Wei Zhou +3 位作者 Zhu-Liang Yang Tolgor Bau Tai-Hui Li Yu-Cheng Dai 《Fungal Diversity》 SCIE 2019年第5期1-76,共76页
The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In th... The huge land areas in China provide highly diverse habitats for macrofungi.Of these macrofungi,many are directly related to people’s daily life and have been utilized by ancient Chinese for at least 6800 years.In this study,we evaluate the current known resource diversity of Chinese macrofungi.A total of 1662 taxa are summarized,and all species names and their authorities have been checked and corrected according to authentic mycological databases.Among the 1662 taxa,1020,692,and 480 are considered to be edible,medicinal and poisonous mushrooms,respectively.A few of edible macrofungi in China are commonly used for commercial production.All known medicinal functions are labeled for medicinal species.The most common medicinal functions possessed by Chinese macrofungi are antitumor or anticancer,followed by antioxidant and antimicrobial.A total of 277 Chinese macrofungi are edible simultaneously with certain medicinal functions and without known toxicity.These species could be treated as“Gold Mushrooms”.Contrarily,193 edible and/or medicinal species are also recognized as poisonous mushrooms.To avoid poisoning caused by these species,ingestion either in a proper way or in small amounts is important.However,the mycotoxins metabolized by these poisonous species could be a huge wealth of natural products yet to be explored.How to utilize these Chinese macrofungal resources is a critical to benefit humans worldwide. 展开更多
关键词 Economic fungi Edible mushroom Fungal toxicity Medicinal function NOMENCLATURE
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红外相机技术在陕西观音山自然保护区兽类监测研究中的应用 被引量:144
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作者 武鹏峰 刘雪华 +4 位作者 蔡琼 何祥博 Melissa Songer 朱云 邵小明 《兽类学报》 CAS CSCD 北大核心 2012年第1期67-71,共5页
国外使用红外相机技术开展野生动物调查研究已有较长的历史,最早的报道见于Champion(1927),在20世纪90年代逐渐发展成熟,广泛用于动物种群数量和密度的研究。
关键词 红外相机技术 陕西观音山自然保护区 相对丰富度 夜行性
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利用红外相机技术分析秦岭有蹄类动物活动节律的季节性差异 被引量:82
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作者 贾晓东 刘雪华 +5 位作者 杨兴中 武鹏峰 Melissa Songer 蔡琼 何祥博 朱云 《生物多样性》 CAS CSCD 北大核心 2014年第6期737-745,共9页
2009年8月至2013年4月期间,在陕西观音山自然保护区,利用18台红外相机收集到羚牛(Budorcas taxicolor)、川西斑羚(Naemorhedus griseus)、中华鬣羚(Capricornis milneedwardsii)、毛冠鹿(Elaphodus cephalophus)、小麂(Muntiacus reeve... 2009年8月至2013年4月期间,在陕西观音山自然保护区,利用18台红外相机收集到羚牛(Budorcas taxicolor)、川西斑羚(Naemorhedus griseus)、中华鬣羚(Capricornis milneedwardsii)、毛冠鹿(Elaphodus cephalophus)、小麂(Muntiacus reevesi)、林麝(Moschus berezovskii)6种有蹄类动物的照片数据,通过相对丰富度指数分析了它们的活动规律及季节性差异。结果表明:(1)6种有蹄类动物在研究区域总丰富度达到了58.71%,其中羚牛的相对丰富度是28.02%,川西斑羚13.24%,毛冠鹿10.08%,中华鬣羚4.21%,小麂2.26%,林麝0.90%。(2)6种有蹄类动物的月相对丰富度反映了其年活动格局,其中羚牛、川西斑羚、毛冠鹿、中华鬣羚、小麂表现出一致性,即夏季活动最为频繁,秋季减弱,冬季达到活动低谷,春季逐渐回升;而林麝则在冬季活动最为频繁,夏季最弱。(3)日时间段相对丰富度反映了动物全年的日活动规律,其中川西斑羚和羚牛相似,主要以白天活动为主;毛冠鹿、小麂、林麝具有明显的晨昏活动习性;中华鬣羚活动高峰出现在02:00–06:00和20:00–22:00,以夜间活动为主。(4)分析不同季节6种有蹄类动物日活动规律,羚牛在春季出现一定的差异,活动高峰出现在16:00–20:00;川西斑羚、毛冠鹿、中华鬣羚在冬季表现出一定的差异,活动高峰相对延迟或者提前;小麂春季表现出差异,活动主要集中在00:00–10:00和18:00–20:00;林麝由于数据相对较少,在4个季节表现出不同的活动规律。(5)夜行性分析得到中华鬣羚具有较强的夜间活动能力,夜间相对丰富度达到了65.81%。这些研究结果有助于监测有蹄类动物种群的变化,为保护区有效保护管理提供了数据支持。 展开更多
关键词 相机陷阱 有蹄类 活动节律 季节性差异
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Leaching and Transformation of Nitrogen Fertilizers in Soil After Application of N with Irrigation: A Soil Column Method 被引量:59
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作者 ZHOU Jian-Bin XI Jin-Gen +1 位作者 CHEN Zhu-Jun LI Sheng-Xiu 《Pedosphere》 SCIE CAS CSCD 2006年第2期245-252,共8页
A soil column method was used to compare the effect of drip fertigation (the application of fertilizer through drip irrigation systems, DFI) on the leaching loss and transformation of urea-N in soil with that of surfa... A soil column method was used to compare the effect of drip fertigation (the application of fertilizer through drip irrigation systems, DFI) on the leaching loss and transformation of urea-N in soil with that of surface fertilization combined with flood irrigation (SFI), and to study the leaching loss and transformation of three kinds of nitrogen fertilizers (nitrate fertilizer, ammonium fertilizer, and urea fertilizer) in two contrasting soils after the fertigation. In comparison to SFI, DFI decreased leaching loss of urea-N from the soil and increased the mineral N (NH4+-N + NO3- -N) in the soil. The N leached from a clay loam soil ranged from 5.7% to 9.6% of the total N added as fertilizer, whereas for a sandy loam soil they ranged between 16.2% and 30.4%. Leaching losses of mineral N were higher when nitrate fertilizer was used compared to urea or ammonium fertilizer. Compared to the control (without urea addition), on the first day when soils were fertigated with urea, there were increases in NH4+-N in the soils. This confirmed the rapid hydrolysis of urea in soil during fertigation. NH4+-N in soils reached a peak about 5 days after fertigation, and due to nitrification it began to decrease at day 10. After applying NH4+-N fertilizer and urea and during the incubation period, the mineral nitrogen in the soil decreased. This may be related to the occurrence of NH4+-N fixation or volatilization in the soil during the fertigation process. 展开更多
关键词 FERTIGATION irrigation method N leaching N transformation nitrogen fertilizer
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四川唐家河自然保护区扭角羚冬春季日活动模式研究 被引量:54
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作者 李明富 李晟 +3 位作者 王大军 William J McShea 官天培 谌利民 《四川动物》 CSCD 北大核心 2011年第6期850-855,共6页
根据相机陷阱调查获得照片的时间,研究了2008年12月~2009年5月唐家河自然保护区内野生扭角羚Budorcastaxicolor的日活动模式。通过对24个1km×1km样方的调查,共完成686个相机工作日的取样量,获得有效的扭角羚捕捉次数709次(冬季322... 根据相机陷阱调查获得照片的时间,研究了2008年12月~2009年5月唐家河自然保护区内野生扭角羚Budorcastaxicolor的日活动模式。通过对24个1km×1km样方的调查,共完成686个相机工作日的取样量,获得有效的扭角羚捕捉次数709次(冬季322次,春季387次),并分别计算出扭角羚冬季和春季在各时间段的相对活动强度指数RAI。结果显示,扭角羚在冬季和春季的日活动模式没有显著差异(χ2检验,P>0.1),每天都有3个活跃时期(凌晨、早上和下午)和3个紧随的不活跃时期。其中,冬季日活动的最高峰出现在下午17:00~18:00(RAI=12.42),最低谷出现在日出前3:00~6:00(RAI=0.00);春季最高峰出现在早上6:00~7:00(RAI=20.16),最低谷出现在日出前2:00~5:00(RAI=0.26)。在春季,扭角羚在上午活跃期的活动强度明显高于下午活跃期,而在冬季则相反。春季与冬季相比,扭角羚上午和下午的两个活跃时间段都有提前,可能是由于不同季节气温和光照差异的影响。研究表明,相机陷阱调查技术是研究野生动物在野外活动模式和活动节律的有效工具,可为今后深入开展扭角羚行为生态学研究和保护区内野生动物的管理提供基础的科学依据。 展开更多
关键词 扭角羚 相机陷阱 日活动模式 相对活动强度指数 唐家河自然保护区
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Shannon-Wiener多样性指数两种计算方法的比较研究 被引量:48
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作者 王晶 焦燕 +3 位作者 任一平 薛莹 纪毓鹏 徐宾铎 《水产学报》 CAS CSCD 北大核心 2015年第8期1257-1263,共7页
在应用群落多样性指数评价调查海域群落物种多样性或进行海域生态环境评价时,常用基于样方数据(方法 1)或基于区域混合样数据(方法 2)2种方法计算Shannon-Wiener多样性指数。为了比较哪种方法所得结果能更好地反映调查海域群落多样性状... 在应用群落多样性指数评价调查海域群落物种多样性或进行海域生态环境评价时,常用基于样方数据(方法 1)或基于区域混合样数据(方法 2)2种方法计算Shannon-Wiener多样性指数。为了比较哪种方法所得结果能更好地反映调查海域群落多样性状况,并且分析多样性指数与样本含量的关系,本实验根据2009年胶州湾潮滩湿地大型底栖动物季度调查数据,应用再抽样模拟方法对2种多样性指数计算方法进行了比较研究。结果表明,对于相同样本含量,基于样方数据计算的Shannon-Wiener多样性指数值小于基于区域混合样数据计算的结果。方法 1所计算的群落多样性指数与样本含量无关;而方法 2计算的多样性指数值随样本含量的增加而增加,并在样本含量为20时接近"真值"并趋于稳定,其相对估计误差(REE)和相对偏差(RB)较小,表明样本含量影响方法 2的多样性指数的计算。在评价调查海域群落物种多样性或进行海域生态环境评价时,应该使用基于区域混合样数据的计算方法,并保证足够的样本含量,才能客观地反映海域群落生物多样性现状。 展开更多
关键词 Shannon-Wiener多样性指数 计算方法 再抽样 最优样本含量
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Terrestrial carbon sinks in China and around the world and their contribution to carbon neutrality 被引量:43
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作者 Yuanhe Yang Yue Shi +25 位作者 Wenjuan Sun Jinfeng Chang Jianxiao Zhu Leiyi Chen Xin Wang Yanpei Guo Hongtu Zhang Lingfei Yu Shuqing Zhao Kang Xu Jiangling Zhu Haihua Shen Yuanyuan Wang Yunfeng Peng Xia Zhao Xiangping Wang Huifeng Hu Shiping Chen Mei Huang Xuefa Wen Shaopeng Wang Biao Zhu Shuli Niu Zhiyao Tang Lingli Liu Jingyun Fang 《Science China(Life Sciences)》 SCIE CAS CSCD 2022年第5期861-895,共35页
Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neu... Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ec 展开更多
关键词 terrestrial ecosystem carbon sink carbon neutrality carbon cycle global warming
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应用红外相机技术研究秦岭观音山自然保护区内野猪的行为和丰富度 被引量:44
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作者 王长平 刘雪华 +4 位作者 武鹏峰 蔡琼 邵小明 朱云 Melissa Songer 《兽类学报》 CAS CSCD 北大核心 2015年第2期147-156,共10页
2009年7月,在陕西观音山自然保护区凉风垭小区域(中高海拔)和西沟小区域(低海拔)安装18台红外相机,2009年8月至2013年4月共收集野猪照片1 195张。定义9种野猪行为,分别为站立、走动、跑动、采食、饮水、修饰、发情、拱土、坐着休息,并... 2009年7月,在陕西观音山自然保护区凉风垭小区域(中高海拔)和西沟小区域(低海拔)安装18台红外相机,2009年8月至2013年4月共收集野猪照片1 195张。定义9种野猪行为,分别为站立、走动、跑动、采食、饮水、修饰、发情、拱土、坐着休息,并逐一比对照片中野猪的行为,统计各种行为所占的比例;引入月相对丰富度和时间段相对丰富度两个指数分别研究野猪的年活动规律和日活动规律;利用一个种群估测模型探讨野猪密度的年际变化。结果表明:(1)春季野猪以走动、采食和站立为主,分别占总行为次数的36%、25.6%和17.4%;夏季野猪以走动、站立、采食和跑动为主,分别占总行为次数的35.7%、23.6%、17%和16.5%;秋季野猪以采食、走动和发情为主,分别占总行为次数的50.3%、19.3%和17.8%;冬季野猪以采食、走动和站立为主,分别占总行为次数的53.7%、26.7%和11.9%。(2)野猪在8月、9月和12月活动较为频繁;全年日活动高峰出现在午后14:00-16:00,低谷出现在22:00-04:00,四季活动规律不同。(3)2009-2012年野猪密度呈逐年上升趋势。这些研究结果有助于了解野猪的行为活动和种群动态,并采取针对性的措施对野猪进行有效管理。 展开更多
关键词 红外相机 野猪 行为 相对丰富度
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Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake,North China:Concentrations,sources profiles and potential risk 被引量:43
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作者 Guocheng Hu Xiaojun Luo +6 位作者 Fengchao Li Jiayin Dai Jianyang Guo Shejun Chen Cao Hong Bixian Mai Muqi Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期176-183,共8页
Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflow... Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China. Total concentrations of OCPs, PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng]g, 2.3 to 197.8 ng/g, and 101.3 to 6360.5 ng]g, respectively. The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake. For hexachlorocyclohexane (HCHs) and dichlorodiphenytrich/oroethanes (DDTs), α-HCH and p,p'-DDT were predominant isomers; while for PCBs, PCB 28/31, PCB 40/103, PCB 60, PCB 101, and PCB 118 were predominant congeners. Possible sources derived from historical usage for OCPs and incomplete combustion fuel, wood, and coal and exhaustion of boats or cars for PAHs. Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact. 展开更多
关键词 persistent organic pollutants CONCENTRATIONS profiles risk assessment Baiyangdian Lake
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Sequencing of Cultivated Peanut, Arachis hypogaea, Yields Insights into Genome Evolution and Oil Improvement 被引量:30
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作者 Xiaoping Chen Qing Lu +23 位作者 Hao Liu Jianan Zhang Yanbin Hong Haofa Lan Haifen Li Jinpeng Wang Haiyan Liu Shaoxiong Li Manish K.Pandey Zhikang Zhang Guiyuan Zhou Jigao Yu Guoqiang Zhang Jiaqing Yuan Xingyu Li Shijie Wen Fanbo Meng Shanlin Yu Xiyin Wang Kadambot H.M.Siddique Zhong-Jian Liu Andrew H.Paterson Rajeev K.Varshney Xuanqiang Liang 《Molecular Plant》 SCIE CAS CSCD 2019年第7期920-934,共15页
Cultivated peanut (Arachis hypogaea) is an allotetraploid crop planted in Asia, Africa, and America for edible oil and protein. To explore the origins and consequences of tetraploidy, we sequenced the allotetraploid A... Cultivated peanut (Arachis hypogaea) is an allotetraploid crop planted in Asia, Africa, and America for edible oil and protein. To explore the origins and consequences of tetraploidy, we sequenced the allotetraploid A. hypogaea genome and compared it with the related diploid Arachis duranensis and Arachis ipaensis genomes. We annotated 39 888 A-subgenome genes and 41 526 B-subgenome genes in allotetraploid peanut. The A. hypogaea subgenomes have evolved asymmetrically, with the B subgenome resembling the ancestral state and the A subgenome undergoing more gene disruption, loss, conversion, and transposable element proliferation, and having reduced gene expression during seed development despite lacking genome-wide expression dominance. Genomic and transcriptomic analyses identified more than 2 500 oil metabolism-related genes and revealed that most of them show altered expression early in seed development while their expression ceases during desiccation, presenting a comprehensive map of peanut lipid biosynthesis. The availability of these genomic resources will facilitate a better understanding of the complex genome architecture, agronomically and economically important genes, and genetic improvement of peanut. 展开更多
关键词 CULTIVATED PEANUT denovo SEQUENCING comparative GENOMICS genome evolution OIL metabolism
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Production of high-quality agarwood in Aquilaria sinensis trees via whole-tree agarwood-induction technology 被引量:31
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作者 Xing Li Zhang Yang Yang Liu +5 位作者 Jian He Wei Yun Yang Zheng Zhang Jun Qing Huang Huai Qiong Chen Yu Jun Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期727-730,共4页
We used whole-tree agarwood-induction technology to produce agarwood from Aquilaria sinensis trees within 20 months, and evaluated the quality of this agarwood. The results showed its characteristics were similar to t... We used whole-tree agarwood-induction technology to produce agarwood from Aquilaria sinensis trees within 20 months, and evaluated the quality of this agarwood. The results showed its characteristics were similar to those of high-grade wild agarwood in terms of texture, chemical constituents, essential oil content, and ethanol-soluble extract content, with the lattermost quality far surpassing the requirement of traditional Chinese medicine agarwood, as indicated in Chinese Pharmacopoeia 2010. To the best of our knowledge, this is first study to show that high-quality agarwood can be produced in whole A. sinensis trees via a chemically induced technology. 展开更多
关键词 AGARWOOD Aquilaria sinensis Chemically induced QUALITY Whole-tree agarwood-induction technology
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TBtools-II: A “one for all, all for one” bioinformatics platform for biological big-data mining 被引量:26
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作者 Chengjie Chen Ya Wu +8 位作者 Jiawei Li Xiao Wang Zaohai Zeng Jing Xu Yuanlong Liu Junting Feng Hao Chen Yehua He Rui Xia 《Molecular Plant》 SCIE CSCD 2023年第11期1733-1742,共10页
Since the official release of the stand-alone bioinformatics toolkit TBtools in 2020,its superior functionality in data analysis has been demonstrated by its widespread adoption by many thousands of users and referenc... Since the official release of the stand-alone bioinformatics toolkit TBtools in 2020,its superior functionality in data analysis has been demonstrated by its widespread adoption by many thousands of users and references in more than 5000 academic articles.Now,TBtools is a commonly used tool in biological laboratories.Over the past 3 years,thanks to invaluable feedback and suggestions from numerous users,we have optimized and expanded the functionality of the toolkit,leading to the development of an upgraded version—TBtools-II.In this upgrade,we have incorporated over 100 new features,such as those for comparative genomics analysis,phylogenetic analysis,and data visualization.Meanwhile,to better meet the increasing needs of personalized data analysis,we have launched the plugin mode,which enables users to develop their own plugins and manage their selection,installation,and removal according to individual needs.To date,the plugin store has amassed over 50 plugins,with more than half of them being independently developed and contributed by TBtools users.These plugins offer a range of data analysis options including co-expression network analysis,single-cell data analysis,and bulked segregant analysis sequencing data analysis.Overall,TBtools is now transforming from a stand-alone software to a comprehensive bioinformatics platform of a vibrant and cooperative community in which users are also developers and contributors.By promoting the theme“one for all,all for one”,we believe that TBtools-II will greatly benefit more biological researchers in this big-data era. 展开更多
关键词 TBtools-ll PLUGIN biological big data BSA-seq
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Long-Term Effect of Fertilizer and Rice Straw on Mineral Composition and Potassium Adsorption in a Reddish Paddy Soil 被引量:30
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作者 LIAO Yu-lin ZHENG Sheng-xian +3 位作者 NIE Jun XIE Jian LU Yan-hong QIN Xiao-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第4期694-710,共17页
Increasing K+ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might... Increasing K+ adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K+ adsorption because of changes in the chemical and mineralogical properties of a rice (Oryza sativa L.). The aims of this study were (i) to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagramdecomposition method; (ii) to measure K+ adsorption isotherms before and after H202 oxidation of organic matter, and (iii) to investigate whether K+ adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr longterm fertilization treatments caused little change in soil organic C (SOC) but a large variation in soil mineral composition. The whole-clay fraction (〈5 Jam) corresponded more to the fertilization treatment than the fine-clay fraction (〈1 gin) in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage ofillite peak area in the 〈5 lam soil particles (R=-0.946, P〈0.0006). Different fertilization treatments gave significantly different results in K+ adsorption. The SOC oxidation test showed positive effects of SOC on K+ adsorption at lower K+ concentration (≤120 mg L-0 and negative effects at higher K+ concentration (240 mg L-l). The K+ adsorption by soil clay minerals after SOC oxidization accounted for 60-158% of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K+ adsorption. The K+ adsorption potential was significantly correlated to the amount of poorly crystallized illite present (R--0.879, P=0.012). The availability of adsorbed K+ for plant growth needs further study. 展开更多
关键词 long-term experiment mineral composition potassium adsorption reddish paddy soil
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Wheat Grain Yield and Yield Stability in a Long-Term Fertilization Experiment on the Loess Plateau 被引量:28
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作者 HAO Ming-De FAN Jun +3 位作者 WANG Quan-Jiu DANG Ting-Hui GUO Sheng-Li WANG Ji-Jun 《Pedosphere》 SCIE CAS CSCD 2007年第2期257-264,共8页
To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fe... To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis. The experiment consisted of 17 fertilizer treatments, containing the combinations of different N and P levels, with three replications arranged in a randomized complete block design. Nitrogen fertilizer was applied as urea, and P was applied as calcium superphosphate. Fertilizer rates had a large effect on the response of wheat yield to fertilization. Phosphorus, combined with N, increased yield significantly (P 〈 0.01). In the unfertilized control and the N or P sole application treatments, wheat yield had a declining trend although it was not statistically significant. Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat. 展开更多
关键词 dryland wheat yield long-term fertilization nitrogen PHOSPHORUS yield stability
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Decoding the evolution and transmissions of the novel pneumonia coronavirus(SARS-CoV-2/HCoV-19)using whole genomic data 被引量:29
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作者 Wen-Bin Yu Guang-Da Tang +1 位作者 Li Zhang Richard T.Corlett 《Zoological Research》 SCIE CAS CSCD 2020年第3期247-257,共11页
The outbreak of COVID-19 started in mid-December2019 in Wuhan, China. Up to 29 February 2020,SARS-CoV-2(HCoV-19/2019-nCoV) had infected more than 85 000 people in the world. In this study,we used 93 complete genomes o... The outbreak of COVID-19 started in mid-December2019 in Wuhan, China. Up to 29 February 2020,SARS-CoV-2(HCoV-19/2019-nCoV) had infected more than 85 000 people in the world. In this study,we used 93 complete genomes of SARS-CoV-2 from the GISAID EpiFlu TM database to investigate the evolution and human-to-human transmissions of SARS-CoV-2 in the first two months of the outbreak.We constructed haplotypes of the SARS-CoV-2 genomes, performed phylogenomic analyses and estimated the potential population size changes of the virus. The date of population expansion was calculated based on the expansion parameter tau(τ)using the formula t=τ/2 u. A total of 120 substitution sites with 119 codons, including 79 non-synonymous and 40 synonymous substitutions, were found in eight coding-regions in the SARS-CoV-2 genomes.Forty non-synonymous substitutions are potentially associated with virus adaptation. No combinations were detected. The 58 haplotypes(31 found in samples from China and 31 from outside China)were identified in 93 viral genomes under study and could be classified into five groups. By applying the reported bat coronavirus genome(bat-RaTG13-CoV)as the outgroup, we found that haplotypes H13 and H38 might be considered as ancestral haplotypes,and later H1 was derived from the intermediate haplotype H3. The population size of the SARS-CoV-2 was estimated to have undergone a recent expansion on 06 January 2020, and an early expansion on 08 December 2019. Furthermore,phyloepidemiologic approaches have recovered specific directions of human-to-human transmissions and the potential sources for international infected cases. 展开更多
关键词 COVID-19 HCoV-19 SARS-CoV-2 Novel pneumonia outbreak Human-to-human transmission Phyloepidemiology
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Effects of plastic film mulching on soil greenhouse gases(CO2,CH4 and N2O) concentration within soil profiles in maize fields on the Loess Plateau,China 被引量:28
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作者 NAN Wei-ge YUE Shan-chao +2 位作者 HUANG Hai-zhou LI Shi-qing SHEN Yu-fang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期451-464,共14页
To better understand the effects of plastic film mulching on soil greenhouse gases(GHGs) emissions,we compared seasonal and vertical variations of GHG concentrations at seven soil depths in maize(Zea mays L.) fiel... To better understand the effects of plastic film mulching on soil greenhouse gases(GHGs) emissions,we compared seasonal and vertical variations of GHG concentrations at seven soil depths in maize(Zea mays L.) fields at Changwu station in Shaanxi,a semi-humid region,between 2012 and 2013.Gas samples were taken simultaneously every one week from non-mulched(BP) and plastic film-mulched(FM) field plots.The results showed that the concentration of GHGs varied distinctly at the soil-atmosphere interface and in the soil profile during the maize growing season(MS).Both carbon dioxide(CO_2) and nitrous oxide(N_2O) concentrations increased with increasement of soil depth,while the methane(CH_4)concentrations decreased with increasement of soil depth.A strong seasonal variation pattern was found for CO_2 and N_2O concentrations,as compared to an inconspicuous seasonal variation of CH_4 concentrations.The mean CO_2 and N_2O concentrations were higher,but the mean CH_4 concentration in the soil profiles was lower in the FM plots than in the BP plots.The results of this study suggested that plastic film mulching significantly increased the potential emissions of CO_2and N_2O from the soil,and promoted CH_4 absorption by the soil,particularly during the MS. 展开更多
关键词 greenhouse gas soil profile plastic film mulching growing season
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敦煌莫高窟顶尼龙网栅栏防护效应研究 被引量:26
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作者 汪万福 王涛 +4 位作者 樊锦诗 张伟民 屈建军 AGNEWN 林博明 《中国沙漠》 CSCD 北大核心 2005年第5期640-648,共9页
野外监测和风洞模拟实验结果表明,孔隙度为20%~25%的尼龙网栅栏,其保护范围达23.5H^29.5H,栅栏前后的积沙范围主要集中在2H(栏前)~3H(栏后)。砂砾质戈壁区尼龙网栅栏直接阻止了偏西风向洞窟搬运沙量的80%以上,但其侧导能力微弱,外围栅... 野外监测和风洞模拟实验结果表明,孔隙度为20%~25%的尼龙网栅栏,其保护范围达23.5H^29.5H,栅栏前后的积沙范围主要集中在2H(栏前)~3H(栏后)。砂砾质戈壁区尼龙网栅栏直接阻止了偏西风向洞窟搬运沙量的80%以上,但其侧导能力微弱,外围栅栏对来自主风向的外侧积沙的侧导率平均达到35%;对其内侧的侧导作用,在偏东风时为57.51%,偏西风时平均为15.89%,反映了防护效益的季节变化特征。在网后1H处,20cm、50cm、100cm和150cm高处的风速分别降到网前3H的48.6%、38.6%、40.7%和66%。在NW风作用下,网后10m、2m的输沙量分别是网前10m、2m的1/29和1/43,并受栅栏设置等因素的影响。流沙区尼龙网栅栏的防沙效益亦表现出在三组不同风向上的差异。栅栏的阻沙效益与沙源供给关系密切,沙源充足时以风积为主,相反,则出现较强的风蚀作用。3~5月间,对比分析前方沙源充足(1992年)、基本控制(2002年)和较好控制(2003年)3种情况,窟前栈道不同部位洞前积沙分别减少39.4%~83.3%、75.4%~95.2%和94.0%~98.7%。尼龙网栅栏是比其他材料更优的一种防沙材料,不仅价格便宜,施工简单,而且在沙障被埋后容易移动重设,在阻止沙丘前移和防止过境风沙流具有优势。目前在网栅周围形成的局部积沙,在综合防护体系逐渐建立,前方沙源截留的前提下,利用窟顶输沙能力的季节变化特别是偏东方的反向搬运功能,局部积沙可以得到较好的输导。同时建议维护调整现有砂砾质戈壁区尼龙网栅栏防护体系。 展开更多
关键词 敦煌莫高窟 尼龙网栅栏 防沙效应
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ClimateAP: an application for dynamic local downscaling of historical and future climate data in Asia Pacific 被引量:29
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作者 Tongli WANG Guangyu WANG +2 位作者 John L.INNES Brad SEELY Baozhang CHEN 《Frontiers of Agricultural Science and Engineering》 2017年第4期448-458,共11页
While low-to-moderate resolution gridded climate data are suitable for climate-impact modeling at global and ecosystems levels, spatial analyses conducted at local scales require climate data with increased spatial ac... While low-to-moderate resolution gridded climate data are suitable for climate-impact modeling at global and ecosystems levels, spatial analyses conducted at local scales require climate data with increased spatial accuracy. This is particularly true for research focused on the evaluation of adaptive forest management strategies. In this study, we developed an application, Climate AP, to generate scale-free(i.e., specific to point locations) climate data for historical(1901–2015) and future(2011–2100)years and periods. Climate AP uses the best available interpolated climate data for the reference period 1961–1990 as baseline data. It downscales the baseline data from a moderate spatial resolution to scale-free point data through dynamic local elevation adjustments. It also integrates and downscales the historical and future climate data using a delta approach. In the case of future climate data, two greenhouse gas representative concentration pathways(RCP 4.5 and 8.5) and 15 general circulation models are included to allow for the assessment of alternative climate scenarios. In addition, Climate AP generates a large number of biologically relevant climate variables derived from primary monthly variables. The effectiveness of the local downscaling was determined based on the strength of the local linear regression for the estimate of lapse rate. The accuracy of the Climate AP output was evaluated through comparisons of Climate AP output against observations from 1805 weather stations in the Asia Pacific region. The local linear regression explained 70%–80% and 0%–50% of the total variation in monthly temperatures and precipitation, respectively, in most cases. Climate AP reduced prediction error by up to27% and 60% for monthly temperature and precipitation,respectively, relative to the original baselines data. The improvements for baseline portions of historical and futurewere more substantial. Applications and limitations of the software are discussed. 展开更多
关键词 biologically relevant climate variables DOWNSCALING dynamic local regression future climate historical climate
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Effect of Nitrogen Management on Yield and Water Use Efficiency of Rainfed Wheat and Maize in Northwest China 被引量:26
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作者 DANG Ting-Hui CAI Gui-Xin +2 位作者 GUO Sheng-Li HAO Ming-De L. K. HENG 《Pedosphere》 SCIE CAS CSCD 2006年第4期495-504,共10页
A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to ... A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to 2002. The local cropping sequence of wheat, wheat-beans, maize, and wheat over the 4-year period was adopted. A micro-plot study using ^15N-lahelled fertilizer was carried out to determine the fate of applied N fertilizer in the first year. When N fertilizer was applied wheat (years 1, 2 and 4) and maize (year 3) grain yield increased significantly (P 〈 0.05) (〉 30%), with no significant yield differences in normal rainfall years (Years 1, 2 and 3) for N application at the commonly application rate and at 2/3 of this rate. Grain yield of wheat varied greatly between years, mainly due to variation in annual rainfall. Results of ^15N studies on wheat showed that plants recovered 36.6%-38.4% of the N applied, the N remained in soll (0-40 cm) ranged from 29.2% to 33.6%, and unaccounted-for N was 29.5%-34.2%. The following crop (wheat) recovered 2.1%- 2.8% of the residual N from N applied to the previous wheat crop with recovery generally decreasing in the subsequent three crops (beans, maize and wheat). 展开更多
关键词 wheat MAIZE ^15N studies water use efficiency YIELD
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