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Influence of canopy on precipitation and its nutrient elements in broadleaved/Korean pine forest on the northern slope of Changbai Mountain 被引量:3
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作者 肖以华 代力民 +3 位作者 牛德奎 佟富春 陈高 邓红兵 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期201-204,251,共4页
The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated... The precipitation distribution quantity of canopy in broadleaved/Korean pine forest was measured during the growing season (Jun.–Sept.) in 2001 in the Changbai Mountain, Jilin Province, P. R. China. Results indicated that the amounts of stemflow, throughfall, and interception were 37.39, 322.12 and 109.69 mm, accounting for 7.97%, 68.65% and 23.38% of the total rainfall, respectively. The rate of stemflow was higher in Jul. and Aug. than other months. The rate of throughfall dropped off from Jun. to Sept., however, rate of interception changed contrarily from 19.43% to 31.02% during the growing season. According to our analysis, the concentration of nutrient elements were arranged as Ca>Mg>N>K>Fe>P>Cu>Mn for rainfall, K>N>Mg>Ca>P>Fe>Mn>Cu for throughfall, and Mn>P>K>Cu>Fe>N>Mg>Ca for being leached through canopy. Nutrients concentration in stewflow and throughfall changed significantly when rainfall passed canopy, and concentration of all elements increased except for Ca and Mg. 展开更多
关键词 Broadleaved/Korean pine forest Precipitation distribution Concentration nutrient elements CANOPY STEMFLOW THROUGHFALL INTERCEPTION
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A Study of the Distribution and Accumulation of Major Nutrient Elements in Different Densities of Eucalyptus grandis 被引量:5
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作者 王丽 龙汉利 +3 位作者 郭洪英 辜云杰 肖兴翠 盛玉珍 《Agricultural Science & Technology》 CAS 2017年第6期1062-1066,共5页
This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: ... This study was conducted to investigate the distribution and accumulation of major elements of 5-year-old Eucalyptus grandis forests with the densities of 556 trees/hm2 and 1 667 trees/hm2. The results showed that: (1) The distribution of ma- jor nutrient element contents in various organs of the E. grandis with the 2 densi- ties was nearly the same, and the ranked order was leaf〉tree trunk〉branch or branchlet〉fruit〉bark. (2) From the distribution of nutrient elements and organic mat- ter in the trunk, P, K, Mg and Ca contents presented basically a trend of increasing with the trunk height increasing. And the organic matter content increased with the trunk height increasing in the low density stand, while the result was opposite in the high density stand. Furthermore, N content increased with the trunk height increas- ing in the low density stand, but the content in the high density stand exhibited a trend of decreasing at first, increasing then and increasing at the last. (3) From the distribution of biomass, the ranked order was tree trunk〉bark or branch〉branchlet〉 leaf〉fruit. And (4) The accumulated amounts of major nutrient elements in various organs under the 2 stand densities was nearly same. Ca content was the highest in the 2 kinds of plantations, followed by N, K, Mg and P contents. Ca content was 601.78 kg/hm2 in the low density stand and 1 204. 43 kg/hm2 in the high density stand. 展开更多
关键词 Eucalyptus grandis Stand density nutrient elements DISTRIBUTION
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Available Contents of Trace Nutrient Element and Factors Affecting Their Availability in Western Jilin 被引量:4
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作者 施宪 王冬艳 +2 位作者 李月芬 靳克 郭珍 《Agricultural Science & Technology》 CAS 2010年第5期73-76,共4页
Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient ele... Based on the assay of the total content and available content of the trace nutrient elements and the soil pH and organic matter of the soil samples,the characteristic of the available content of the trace nutrient elements and their affecting factors are studied. The results show that the available B in western Jilin is in a middle level,the content in Nong'an is higher than that in the others; the available Mn is extremely abundant; the available Cu in Nong'an is obviously higher than other areas,and the content in Da'an differs greatly; the available Zn is in a middle level; the severe shortage of available Mo differs between different areas; and the available Fe is extremely abundant. The available Mn,Cu and Fe have significantly positive correlation with their total content; the available B has significantly positive correlation with pH,and Zn has obviously negative correlation with pH; the available Mn and Fe had significantly positive correlation with soil organic matter. 展开更多
关键词 Trace nutrient element Available content The affecting factors Western Jilin
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Distribution and Accumulation of Nutrient Elements in Organic Tissue of Eucalyptus grandis Saplings 被引量:1
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作者 闵安民 王宇 +2 位作者 李红霞 费楠 李凤鸣 《Agricultural Science & Technology》 CAS 2015年第12期2749-2753,2880,共6页
The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of n... The biomass, macroelements (N, P, K, Ca, Mg) and microelements (Fe, Zn) contents were detected in organs of 1a-3a Eucalyptus grandis saplings, as well as their accumulated amount. Results showed that contents of nutrient elements varied greatly in different organs. Total contents of macroelements N, P, K, Ca and Mg in1a-3a E. grandis were distributed in the order of stem phloem, leaves 〉 branch- es, roots 〉 stem xylem. Accumulated amount of macroelements in 1a-3a E. grandis were in the order of leaves 〉 branches 〉 stem phloem 〉 roots or stem xylem 〉 stem xylem or roots. Accumulated amount law of nutrient elements was not affected by the plant age. Microelements Fe and Zn were mainly concentrated in the leaves and roots. The accumulation of macroelements was in the order of Ca 〉 N 〉 K 〉 Mg 〉 P; and the microelements was in the order of Fe 〉 Zn. Accumulated amounts of microelements in 1a-3a E. grandis were 12.45 136.19 and 420.23 g per plants, respectively. Among the annual net accumulated amount of nutrient ele- ments per plant in 1a-3a E. grandis, Ca element was the maximum, N and K ele- ments took the second and third places. Mg element was relatively small and P el- ement was the minimum. 展开更多
关键词 Eucalyptus grandis ORGAN nutrient element Accumulated amount
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Variations of nutrient elements and its effect on ecological environment off the Changjiang estuarine waters 被引量:2
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作者 Lin Yi’ an, Tang Renyou, Pan Jianming, Jin Mingming ( Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第2期197-208,共11页
On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The trans... On the basis of the date obtained in two cruises during October 1997 and May 1998, the concentration distribution and the variation of present species of nutrient elements in the water masses are described. The transform mechanism of present species of nutrients and the of differrnt water masses, frontal area and thermohaline transition layer on convergence or divergence and the biogeochemical cycle of nutrient elements off the Changjiang Estuary are studied. Meanwhile, the environmental capaci- ty of nutrients is primarily estimated: they are 1.803 x 104t DIN and 6.18 x 102t PO43- -P in autumn, and 4.20x 102t PO43- -P in spring. 展开更多
关键词 nutrient element biogeochemical cycle ecological environmental effect the Changjiang Estuary
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Reanalysis of the Atmospheric Flux of Nutrient Elements to the Southern Yellow Sea and the East China Sea 被引量:2
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作者 万小芳 吴增茂 常志清 《Marine Science Bulletin》 CAS 2003年第1期45-51,共7页
Based on the recent research results on dry and wet deposition of nutrient elements and sulphate, we estimate the atmospheric flux of nutrient elements and sulphate to the southern Yellow Sea and the East China Sea in... Based on the recent research results on dry and wet deposition of nutrient elements and sulphate, we estimate the atmospheric flux of nutrient elements and sulphate to the southern Yellow Sea and the East China Sea in each season. The results suggest that the concentrations of nutrient elements and sulphate in aerosol and precipitation show an apparent seasonal cycle with the maximum values in winter and the minimum values in summer. Depositions of nitrate and sulphate are dominated by wet deposition, while the deposition for phosphate is mainly dry deposition. Moreover, compared with the riverine inputs, the atmospheric deposition may be the main source of dissolved inorganic nutrients in the southern Yellow Sea and the East China Sea. 展开更多
关键词 the southern Yellow Sea the East China Sea nutrient elements atmospheric flux
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Study on the Changes of the Major Nutrient Elements During Simple Composting Process of Dry Chicken Manure 被引量:2
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作者 Jintao XU Longfei LI +4 位作者 Lijuan GAO Yong GUO Hai'e ZHANG Minghui JI Baofeng HAO 《Agricultural Biotechnology》 CAS 2020年第6期95-98,103,共5页
[Objectives]This study was conducted to provide a theoretical basis for production and application of chicken manure compost.[Methods]With dry manure as a material,the variations of the major nutrients during simple c... [Objectives]This study was conducted to provide a theoretical basis for production and application of chicken manure compost.[Methods]With dry manure as a material,the variations of the major nutrients during simple composting process of dry chicken manure were studied,in order to get the best fermentation method.[Results]Chicken manure should not be preserved wet,but should be preserved after air-drying and fermented before use.Necessary moisture,simple sealing treatment and a certain amount of N element were conducive to simple fermentation of chicken manure.The treatments in which the chicken manure was wrapped around and compacted,added with an appropriate amount of water(50%-60%)and naturally fermented,or was wrapped around and compacted and added with an appropriate amount of water(50%-60%)and 0.2%of urea,were more appropriate for the production directly.[Conclusions]This study provides a theoretical basis for the actual production and application of chicken manure compost. 展开更多
关键词 Chicken manure Simple composting process nutrient element Changing relationship
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Regression Analysis of Nutrient Elements between Soil and Tobacco Leaves and Their Influences on Aroma Quality of Flue-cured Tobacco 被引量:1
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作者 Xueqin XU Xiaolan LI +2 位作者 Zhiyan CHEN Defen ZENG Aifei XU 《Agricultural Science & Technology》 CAS 2014年第3期493-498,共6页
This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences... This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences of these elements on chemical composition and aroma components in tobacco leaves. Results showed that there were certain relationship between contents of nutrient elements in tobacco-planting soils and contents of corresponding elements in tobacco leaves; various elements exhibited different influences on the aroma quality of flue-cured tobacco. Based on the actual situation of nutrient contents in soils from different tobaccoproducing areas, contents of various elements in tobacco leaves should be regulated by soil fertilization and foliar spraying, thereby improving the aroma quality of flue-cured tobacco. 展开更多
关键词 SOIL TOBACCO nutrient elements Regression analysis Aroma quality
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COMPARATIVE ANALYSES ON THE LITTER IN KOREAN PINE MONGOLIAN SCOTS PINE AND DAHURIAN LARCH PLANTATIONS(Ⅱ)CONTENT AND RETURNING AMOUNT OF NUTRIENT ELEMENTS
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作者 王克 张羽 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第1期12-17,共6页
Comparative analyses were conducted on the nutrient element content and returning amount of main fractional compositions of litter in Korean pine (KP), Mongolian Scots pine(MSP) and Dahurian larch (DL) plantations in ... Comparative analyses were conducted on the nutrient element content and returning amount of main fractional compositions of litter in Korean pine (KP), Mongolian Scots pine(MSP) and Dahurian larch (DL) plantations in Laoshan Plantation Experiment Station of Maoershan Experiment Forest Farm of Northeast Forestry University. The results are as follows: (1) The nutrient element content and returning amount in litter varies among different fractional compositions and tree species, the total returning amount of all nutrient elements and the returning amount of K, Ca, Mg, N and P are DL>MSP>KP, the returning amount of Cu is DL>KP>MSP, the returning amount of Fe and Mn are MSP>DL>KP, (2) To KP and DL plantations, the main nutrient element returned is dead needles; dead branches, bark scales and dead cones account for a little proportion; whereas to MSP plantation, besides dead needles,dead branches and bark scales also play an important role in the return of nutrient elements; (3)A little deal of dead leaves can provided a great deal of returning amount of nutrient elements. 展开更多
关键词 Korean pine Mongolian Scots pine Dahurian larch PLANTATION Litter nutrient elements Returning amount
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Soil Nutrient Elements of Trampling Disturbance Kobresia humilis Communities along the Highway in Na’qu, Tibet
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作者 ZHANG Jinhua LI Chenqiong +2 位作者 YAN Yan ZHONG Li QIN Taoying 《Wuhan University Journal of Natural Sciences》 CAS 2009年第2期174-178,共5页
The change of soil nutrient elements during restoration succession processes of high mountain meadow in Na'qu County, Tibet, was investigated. The results showed that with the trampling disturbance, the normal struct... The change of soil nutrient elements during restoration succession processes of high mountain meadow in Na'qu County, Tibet, was investigated. The results showed that with the trampling disturbance, the normal structure of soil is violated, soil quality worsened, leading to soil erosion and nutrient loss. The recoverage of soil is lagged behind vegetation when change depends on elements of soil nutrient increase in mass. The content of total nitrogen, total phosphorus and total potassium changed accordingly with total nutrient, and is remarkably correlated to the content of organic matter. The content of available phosphorus is complex and changes with biomass and soil pH. The content of available potassium change was different from that of total nitrogen, total phosphorus and total potassium, and was increasing with trampiing, and the change was relatively little during successive stages. 展开更多
关键词 degenerated meadow recoverage succession soil nutrient elements
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Transport patterns of micro nutrient elements from the continental shelf of the East China Sea to the Kuroshio area
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作者 Lu Saiying, Yao Qiao’er and Chen Zhen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第2期219-230,共12页
On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviousl... On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advec-tion and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advec-tion process and the upwelling degree of the subsurface Kuroshio water to the shelf.4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area. 展开更多
关键词 Transport patterns of micro nutrient elements from the continental shelf of the East China Sea to the Kuroshio area
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Variations of nutrient element contents of plants and soils in the process of karst rocky desertification 被引量:1
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作者 Liping XIE Shijie WANG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期176-176,共1页
关键词 喀斯特 土壤 植物 生态系统 营养元素
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Effects of Different Seed Stem Sizes on the Changes of Available Elements in Rhizosphere Soil of Fritillaria thunbergii Miq.
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作者 Yong PENG Rui PAN +3 位作者 Zhengyan LIU Xiaohong WU Nong ZHOU Wenwu YANG 《Agricultural Biotechnology》 2024年第3期18-23,共6页
[Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F... [Objectives]This study was conducted to screen suitable seed stems of Fritillaria thunbergii Miq.from different provenances and to provide a theoretical basis for the high-yielding and high-efficiency cultivation of F.thunbergii Miq.introduced to different places.[Methods]F.thunbergii Miq.from four different provenances including Zhejiang,Nantong and Chongqing were introduced and cultivated in Wanzhou of Chongqing.The contents of available Zn,Fe,Mn,Cu,Mo,N,P,K,Ca and Mg in rhizosphere soil of F.thunbergii Miq.during five growing stages were determined after selecting different stem sizes for field cultivation.[Results]Small stems of Pan an and Ningbo provenances(SSG3,121-160/kg)and middle stems of Nantong and Fengjie provenances(SSG2,81-120/kg)showed higher soil availability.[Conclusions]In the process of introduction and cultivation of F.thunbergii Miq.,high yield and high efficiency can be achieved by selecting smaller seed stems of F.thunbergii Miq. 展开更多
关键词 Fritillaria thunbergii Miq. Different provenances Stem size INTRODUCTION CULTIVATION Soil nutrient element AVAILABILITY
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Technique of wheat breeding for efficiently utilizing soil nutrient elements
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作者 李继云 刘秀娣 +6 位作者 周伟 孙建华 童依平 刘文杰 李振声 王培田 姚树江 《Science China Chemistry》 SCIE EI CAS 1995年第11期1313-1320,共8页
500 wheat varieties were grown and screened,and 18 of them with better characters identified inthe low phosphorus,low zinc,low boron soil and in contrast with the control(appilied with N,P,Zn andB).A few varieties sho... 500 wheat varieties were grown and screened,and 18 of them with better characters identified inthe low phosphorus,low zinc,low boron soil and in contrast with the control(appilied with N,P,Zn andB).A few varieties showed able to efficiently utilize P,Zn or B in soil,and it has been demonstrated by theanalysis that their roots can secrete more organic acids making the soil pH around the roots decrease.Six or-ganic acids in the roots of four representative varieties were analysed,their contents were of difference amongthe varieties and had a positive correlation with the yield of the varieties in low nutrition soil.All theabove-mentioned provided the scientific basis of crop breeding for efficient utilization of soil nutritions. 展开更多
关键词 wheat BREEDING efficient utilization nutrient elementS ROOT SECRETION
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深圳湾表层沉积物砷、镉、汞和营养元素的分布与富集特征 被引量:1
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作者 甘华阳 林海 何海军 《海洋地质与第四纪地质》 北大核心 2025年第1期42-52,共11页
基于2020年的调查资料研究了深圳湾(深圳管辖区)表层沉积物中砷、镉、汞和氮、磷等营养元素的含量、空间分布、富集、来源以及生态风险等特征,深圳湾表层沉积物中As、Cd、Hg、TN、TP和TOC的含量分别为16.46±3.78μg/g、0.26±0... 基于2020年的调查资料研究了深圳湾(深圳管辖区)表层沉积物中砷、镉、汞和氮、磷等营养元素的含量、空间分布、富集、来源以及生态风险等特征,深圳湾表层沉积物中As、Cd、Hg、TN、TP和TOC的含量分别为16.46±3.78μg/g、0.26±0.10μg/g、0.110±0.044μg/g、947±281μg/g、631±214μg/g和1.41%±0.41%。三种重金属含量在内湾深圳河口外和蛇口港沿岸相对较高;TN、TP和TOC含量则在内湾含量较高。排污等人类活动输入导致了TN、TP、As和Cd在深圳湾表层沉积物中富集,其中TN在整个海湾都明显富集,后三者则主要富集于内湾的深圳河口、北部沿岸和湾口港口区。As、Cd可能主要来源于港口船只排污,而TN、TP则可能主要来源于沿岸污水溢流。虽然深圳湾大部分海域表层沉积物中As、Cd、Hg和TOC含量均低于我国沉积物质量一类标准阈值,满足目前一般工业用水、滨海风景旅游的环境功能要求,但As、TN、TOC和TP含量仍可能会对某些敏感底栖生物产生负面影响,需持续保持关注。 展开更多
关键词 重金属 营养元素 表层沉积物 生态风险 深圳湾
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白鲜不同生育时期营养元素积累规律及分配特征
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作者 邵财 孙海 +3 位作者 关一鸣 金桥 王秋霞 张亚玉 《东北林业大学学报》 CAS 北大核心 2025年第1期35-42,共8页
以3年生白鲜(Dictamnus dasycarpus)为研究对象,通过测定白鲜不同生育时期根、茎、叶的干质量及营养元素含量,分析白鲜不同生育时期营养元素积累规律及分配特征,为白鲜科学精准施肥提供理论依据。结果表明:白鲜在生长过程中,不同营养元... 以3年生白鲜(Dictamnus dasycarpus)为研究对象,通过测定白鲜不同生育时期根、茎、叶的干质量及营养元素含量,分析白鲜不同生育时期营养元素积累规律及分配特征,为白鲜科学精准施肥提供理论依据。结果表明:白鲜在生长过程中,不同营养元素的积累量由大到小的顺序为氮(N)、钙(Ca)、磷(P)、钾(K)、镁(Mg)、铁(Fe)、锰(Mn)、锌(Zn)、铜(Cu);在生长初期,N、P、K质量分数相对较高,植物对N、P、K元素的需求较大;出苗期至花蕾期,白鲜根中N、P、K的积累量分配比例明显降低,茎叶中积累量分配比例明显增加;从果前期开始,白鲜茎叶中Ca、Mg质量分数和积累量显著增加,在茎叶中分配比例相对较高;果前期和果中期茎叶中Fe、Mn质量分数显著增加,Fe、Mn元素积累量在果中期相对较高,茎叶中分配比例有所增加;根中Zn质量分数从果前期至果中期显著增加,整株积累量显著增大,果中期在根中分配比例达到最大,白鲜茎叶中Cu、Zn质量分数在花蕾期相对较高,在茎叶中的分配比例达到最大。因此,白鲜出苗期至花蕾期需要补充大量元素(N、P、K)及微量元素(Cu、Zn),果前期至果熟期需要补充中量元素(Ca、Mg)和微量元素(Fe、Mn、Zn)。 展开更多
关键词 白鲜 营养元素 积累 分配 合理施肥
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锌肥随水滴施对新疆绿洲棉田土壤养分的影响
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作者 李全胜 高志建 +2 位作者 于航 王国栋 刘瑜 《新疆农业科学》 北大核心 2025年第6期1308-1317,共10页
【目的】研究随水滴施锌肥对棉田土壤养分的影响,为指导锌肥随水滴灌施用提供理论依据。【方法】设置田间小区试验,在棉花生育期设置随水滴施不同用量锌肥处理,分别为0 kg/hm^(2)(CK)、7.5 kg/hm^(2)(Zn1)、15 kg/hm^(2)(Zn2)、22.5 kg/... 【目的】研究随水滴施锌肥对棉田土壤养分的影响,为指导锌肥随水滴灌施用提供理论依据。【方法】设置田间小区试验,在棉花生育期设置随水滴施不同用量锌肥处理,分别为0 kg/hm^(2)(CK)、7.5 kg/hm^(2)(Zn1)、15 kg/hm^(2)(Zn2)、22.5 kg/hm^(2)(Zn3)、30 kg/hm^(2)(Zn4)、37.5 kg/hm^(2)(Zn5)、45 kg/hm^(2)(Zn6),分析不同锌肥滴施用量条件0~20 cm和20~40 cm土壤中主要养分含量的变化特征。【结果】随着锌肥施用量的增加,0~20 cm土层有效锌含量呈逐渐增加趋势,20~40 cm土层呈波动变化;同不施锌肥相比,锌肥施用降低了0~20 cm和20~40 cm棉田土壤pH值,并提高碱解氮、有效磷含量,其中碱解氮、有效磷含量均在Zn3处理时含量最高,分别为84.16和84.68 g/kg、31.93和30.40 g/kg;0~20 cm和20~40 cm棉田土壤速效钾、有效铁含量随着锌肥施用量的增加呈先增加后降低的趋势,并且均在Zn4处理时含量最高,为548.33和552.00 g/kg、10.35和10.55 mg/kg;0~20 cm和20~40 cm棉田土壤有效锰和交换性镁随着锌肥施用量的增加呈逐渐增加的趋势,并且均在Zn6处理时含量最高,分别为5.0和5.0 mg/kg、4.48和4.48 mg/kg。【结论】不同锌肥用量试验,当硫酸锌滴施量为22.5~30.0 kg/hm^(2)时,土壤pH值下降,碱解氮、有效磷、速效钾、有效锌、有效铁含量均处于较高值,有效锰、交换性镁则在锌滴施量为45 kg/hm^(2)时,含量最高,滴施锌肥对提升新疆绿洲棉田灌耕灰漠土的土壤肥力有正向的作用。 展开更多
关键词 锌肥 随水滴施 棉花 土壤养分 微量元素
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高寒沙地2种密度沙柳人工林叶片、枝条和土壤养分特征
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作者 李清雪 贾志清 +3 位作者 何凌仙子 张佳鹏 赵雪彬 羊秀本 《生态学报》 北大核心 2025年第18期9230-9241,共12页
以青海共和盆地高寒沙地2种密度衰退沙柳人工林为研究对象,测定叶片、枝条和土壤养分含量,并计算其化学计量比,分析植物和土壤的养分含量及其化学计量比之间的关系,揭示人工林生长的主要限制因素,为高寒沙区植被恢复与重建及可持续经营... 以青海共和盆地高寒沙地2种密度衰退沙柳人工林为研究对象,测定叶片、枝条和土壤养分含量,并计算其化学计量比,分析植物和土壤的养分含量及其化学计量比之间的关系,揭示人工林生长的主要限制因素,为高寒沙区植被恢复与重建及可持续经营提供理论依据。结果表明:(1)高密度林叶片和枝条的C、N、P、K含量都高于低密度林,C∶N、C∶P、C∶K低于低密度林,说明低密度林对N、P、K元素的利用效率较高。(2)2种密度人工林叶片的N∶P分别为18.37和19.11,林木生长都受到P元素的限制。(3)低密度林3个土壤深度的SOC、TN和AK含量都明显高于高密度林,AN和AP含量及pH值明显低于高密度林,对土壤养分指标的综合评价结果为低密度林土壤质量指数较高。低密度林3个深度土壤的C∶P(0—20cm除外)和N∶P都明显高于高密度林,C∶N明显低于高密度林,说明低密度林提高了N的有效性,降低了P的有效性,P对低密度林生长的限制性更强。(4)RDA分析表明,土壤TN(0—60cm)和AK(40—60cm)含量对沙柳叶片的C、N、P、K含量及其化学计量比的解释程度最高,且都达到显著水平(P<0.05),土壤TN和AK含量与沙柳C、N、P、K含量呈负相关关系。 展开更多
关键词 高寒沙地 沙柳人工林 密度 养分元素 化学计量比
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原榨果汁中多酚和多元素的含量特征及营养分析
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作者 李轶 卢岚 +5 位作者 李谭瑶 李帮锐 李欣 鲁兵 伍碧珍 陈东洋 《卫生研究》 北大核心 2025年第4期566-572,581,共8页
目的对电商平台采购的11种原榨果汁中多酚和多元素进行含量测定,掌握其含量特征及进行营养评价。方法使用pH示差法、Folin-Ciocalteu试剂比色法、电感耦合等离子体质谱法、直接测汞法分别测得果汁中的总花色苷、总多酚和16种多元素的含... 目的对电商平台采购的11种原榨果汁中多酚和多元素进行含量测定,掌握其含量特征及进行营养评价。方法使用pH示差法、Folin-Ciocalteu试剂比色法、电感耦合等离子体质谱法、直接测汞法分别测得果汁中的总花色苷、总多酚和16种多元素的含量,用营养素密度(nutrient density,ND)和营养质量指数(index of nutrient quality,INQ)进行营养分析。结果果汁中总花色苷含量为未检出~1664 mg/L,蓝靛果汁含量最高;总多酚含量为281~2948 mg/L,刺梨汁含量最高。常量元素以钾含量最高(288~1996 mg/L),微量元素以锰含量最高(0.2~17.7 mg/L)。果汁中总花色苷的ND为0~332.8%,钾、钙、钠、镁、铁、锌、铜和硒的ND偏低,均小于10%,锰、铬、钼的ND较高,分别为0.4%~39.3%、0.7%~35.3%和0~13.2%。果汁中总花色苷的INQ范围是0~167.63,除沙棘汁和刺梨汁外,其他品种果汁中总花色苷的INQ均大于1。果汁中钾、铁的INQ均小于6,钙和锌的INQ小于2,镁和铜的INQ均小于4,钠的INQ小于3,锰、铬和钼的INQ更高,分别是0.21~24.00、0.27~15.76和0~7.18。硒的INQ全部小于1。结论原榨果汁(除沙棘汁、刺梨汁和加拿大蔓越莓汁外)可作为花色苷良好的来源。蓝莓汁、中国黑龙江蔓越莓汁、德国黑莓汁、红树莓汁、黑果枸杞汁、中国辽宁野樱莓汁和沙棘汁还可以为人体补充锰、铬和钼。但它们的钾、钠、钙、镁、铁、锌、铜和硒不能满足人体的需求。 展开更多
关键词 果汁 多酚 元素 营养素密度 营养质量指数
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长期化肥配施不同有机物料对亚热带稻田土壤微生物生物量及酶化学计量特征的影响 被引量:1
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作者 李雪 周萍 +5 位作者 程爱武 戴玉婷 赖佳鑫 李康祺 盛浩 吴金水 《植物营养与肥料学报》 北大核心 2025年第2期305-316,共12页
【目的】利用肥料长期定位试验,研究化肥与不同有机物料配施下,亚热带稻田土壤的微生物生物量碳氮磷含量、土壤胞外酶活性及其化学计量比的差异,揭示不同有机肥源对土壤微生物生物量稳定性的影响特征。【方法】依托位于湖南省宁乡市农... 【目的】利用肥料长期定位试验,研究化肥与不同有机物料配施下,亚热带稻田土壤的微生物生物量碳氮磷含量、土壤胞外酶活性及其化学计量比的差异,揭示不同有机肥源对土壤微生物生物量稳定性的影响特征。【方法】依托位于湖南省宁乡市农技中心的稻田长期定位试验(始于1986年),选取5个施肥处理,分别为不施肥对照(CK)、单施化肥(NPK)、30%猪粪有机肥替代化肥氮(30%OM)、60%猪粪有机肥替代化肥氮(60%OM)、秸秆还田+化肥(NPKS),种植制度为一年三熟,早稻-晚稻-大麦轮作。于2022年9月晚稻成熟期采集表层(0—20 cm)土壤样品,测定土壤有机碳(SOC)、全氮(TN)、全磷(TP)含量,微生物生物量碳、氮、磷(MBC、MBN、MBP)含量和β-葡萄糖苷酶(βG)、β-N-乙酰氨基葡萄糖苷酶(NAG)、酸性磷酸酶(ACP)活性,并计算化学计量比。【结果】长期施肥显著提高了土壤SOC、TN和TP含量,60%OM处理3个指标的增幅均最高(P<0.05),30%OM处理的增幅也显著高于NPK处理,而NPKS处理的TN增幅与NPK处理相当。3个有机无机肥配合处理之间土壤C/N无显著差异,而NPKS处理的C/P和N/P均显著高于60%OM和30%OM处理。3个有机无机肥配合处理MBC含量无显著差异,均高于NPK处理;MBN和MBP含量均以60%OM处理最高,显著高于其他处理,其次为30%OM处理,NPKS处理MBN含量高于NPK处理,而MBP含量与NPK处理相当,因而NPKS处理的MBC/MBN和MBC/MBP均显著高于两个猪粪处理,低于NPK处理。与CK相比,NPK处理仅显著增加了βG活性,而有机无机肥配施提高了土壤βG、NAG和ACP活性,30%OM处理土壤中的βG/NAG和βG/ACP显著高于NPK处理,而60%OM处理则显著低于NPK处理。相关性分析表明,土壤微生物生物量及其化学计量,以及βG和ACP活性,均与土壤碳、氮、磷含量及其化学计量呈正相关。进一步冗余分析表明,土壤TP含量和N/P是驱动土壤微生物生物量及其化学计量变化的关键因子。【结论】长期将化肥与有机肥配合施用,能显著提升稻田土壤的有机碳、全氮和全磷含量,同时增加微生物生物量和胞外酶活性。其中,以60%的猪粪替代化肥氮的效果最为突出,不仅显著提高了土壤碳、氮、磷的含量,而且显著增加了微生物生物量碳、氮、磷含量,但降低了胞外酶化学计量比,并维持较低的胞外酶化学计量平衡。因此,猪粪与氮磷钾配施通过增加土壤有机碳、氮、磷投入,维持较稳定的积累,进而提升土壤肥力,提高适应环境变化的能力。而氮磷钾与秸秆配施可能造成土壤磷素的限制,降低土壤养分的供应能力。 展开更多
关键词 长期试验 亚热带稻田 土壤养分 微生物生物量 土壤酶活性 元素化学计量
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