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论蒙元时期钦察人土土哈家族 被引量:1
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作者 杨继红 《内蒙古农业大学学报(社会科学版)》 2009年第3期317-318,共2页
在蒙元时期,钦察人土土哈及其后人累代簪缨,是最为显赫的钦察阀阅世家。土土哈家族几乎伴随着元朝从建立到消灭的全过程,在元朝的政治、军事方面发挥过显著的作用。是元朝时钦察人的一个缩影。
关键词 钦察 土土 床兀儿 燕铁木儿 唐其势
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从土土哈任官履历看钦察人在元朝地位的变化
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作者 乌兰 《今古文创》 2021年第35期57-58,共2页
纵观其钦察人在元朝中的官职担任史,是极其活跃的。本文主要讲述入降蒙古之后的钦察人土土哈在蒙元时期担任的官职演变过程。在此重点利用苏天爵的《元朝名臣事略》来列出土土哈的三次重要的担任官职状况,并用其他材料如虞集《句容郡王... 纵观其钦察人在元朝中的官职担任史,是极其活跃的。本文主要讲述入降蒙古之后的钦察人土土哈在蒙元时期担任的官职演变过程。在此重点利用苏天爵的《元朝名臣事略》来列出土土哈的三次重要的担任官职状况,并用其他材料如虞集《句容郡王世纪碑》等文献内容作为补充。随之附上笔者的拙见:如土土哈的官职演变原因探析与随之而来的钦察人的待遇。 展开更多
关键词 钦察人 土土 官职 同知枢密院事
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软土土工试验中有关问题分析
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作者 许春莲 《科学中国人》 2015年第4Z期54-,共1页
现如今,我国的经济和科技都在不断发展,其中包括市政工程、工业工程以及其他的建筑类型等等。另外,在具体的水利设施中都需要进行室内的土木实验。为了获得更加准确的实验数据,工作人员需要按照科学的软土土工试验的顺序以及流程来进行... 现如今,我国的经济和科技都在不断发展,其中包括市政工程、工业工程以及其他的建筑类型等等。另外,在具体的水利设施中都需要进行室内的土木实验。为了获得更加准确的实验数据,工作人员需要按照科学的软土土工试验的顺序以及流程来进行,并且对相关的实验数据进行缜密地分析,在保证工程项目建设安全性和稳定性的前提下保证工程的整体质量。本文中,笔者主要对南方地区软土试验的一般规律和重点问题进行深入分析,旨在解决软土土工试验中的相关问题。 展开更多
关键词 土土工试验 问题 分析
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花木移栽为什么要带母土土球
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作者 杜德民 崔百喜 《中国林业》 2004年第12A期42-42,共1页
关键词 移栽成活率 花木 带母土土 道理
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土土土
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作者 汤汤 阿卡伊(图) 《儿童文学》 2010年第8期66-73,共8页
我每天都在寻找瞳孔里开着烟灰色花朵的人。瞳孔里的花,小小的、灰灰的,有五个或者六个花瓣——只是大多数人都看不见哦。我是谁?你不可能猜得到。我假装成一个人,住在城市的六十楼。我姓土,名土土,所以我叫做土土土。我喜欢这个... 我每天都在寻找瞳孔里开着烟灰色花朵的人。瞳孔里的花,小小的、灰灰的,有五个或者六个花瓣——只是大多数人都看不见哦。我是谁?你不可能猜得到。我假装成一个人,住在城市的六十楼。我姓土,名土土,所以我叫做土土土。我喜欢这个名字。 展开更多
关键词 小说 文学作品 现代文学 土土土》
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整体式桥梁动力特性及抗震性能研究
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作者 郑梦洋 梁喜燕 +2 位作者 宋旭明 牛安心 唐冕 《地震工程学报》 CSCD 北大核心 2023年第6期1369-1376,共8页
为深入了解整体式桥梁的动力特性和抗震性能,建立台-土有限元模型,并提出合理的台-土相互作用数学模型,然后利用Midas Civil整体模型研究台-土相互作用、桩-土相互作用、桥墩构造等因素对整体式桥梁抗震性能的影响。结果表明:与简支梁相... 为深入了解整体式桥梁的动力特性和抗震性能,建立台-土有限元模型,并提出合理的台-土相互作用数学模型,然后利用Midas Civil整体模型研究台-土相互作用、桩-土相互作用、桥墩构造等因素对整体式桥梁抗震性能的影响。结果表明:与简支梁相比,同等跨度下整体式桥梁的纵向刚度明显提高,但横向刚度差距不大;台后土的约束刚度大小对桥梁的静动力特性不产生明显影响,整体式桥梁根据我国现有规范计算台后地震力相对保守;改变桩-土约束刚度对整体式桥梁的抗震性能影响不大;提高桥墩的横向刚度,将独柱墩改为双柱墩能大幅提高结构抗震性能。研究结论及台后土压力系数的计算方式,可供整体式桥梁抗震计算提供参考。 展开更多
关键词 整体式桥梁 动力特性 抗震性能 台-土相互作用 台后土土压力系数
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土力学发展的四个阶段的思考 被引量:5
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作者 杨光华 《岩土工程学报》 EI CAS CSCD 北大核心 2022年第9期1730-1732,共3页
土力学的发展以变形特性作为依据,可以分为四个阶段。第一阶段主要是研究土的一维压缩变形,以压缩试验的e–p曲线为标志;第二阶段是研究土的三维压缩变形的形态,以Roscoe的临界状态面为标志,建立e–p–q的三维曲面;第三阶段是以Duncan-C... 土力学的发展以变形特性作为依据,可以分为四个阶段。第一阶段主要是研究土的一维压缩变形,以压缩试验的e–p曲线为标志;第二阶段是研究土的三维压缩变形的形态,以Roscoe的临界状态面为标志,建立e–p–q的三维曲面;第三阶段是以Duncan-Chang本构模型为标志,以土的压硬性和剪软性为特点,更直观地以土的剪切变形研究为主;第四阶段应该是以现场原位土为研究对象,以原位测试技术为主要手段,掌握原位土的力学特性,发展原位土土力学,更好地服务于工程实际。第四阶段应该是今后值得努力的方向。 展开更多
关键词 土的压缩 土的临界状态面 原位土土力学
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路基结构性能衰变影响因素与机理分析 被引量:3
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作者 李冬雪 孙宗元 《路基工程》 2014年第6期42-45,50,共5页
准确掌握路基结构性能与湿度的相关性,并且能够进行科学的表征,是完善"力学-经验"设计法的基础。鉴于此,综述了路基结构性能的主要影响因素,并探讨了路基结构性能的衰变机理。结果表明:应力状态与路基湿度对路基结构性能影响... 准确掌握路基结构性能与湿度的相关性,并且能够进行科学的表征,是完善"力学-经验"设计法的基础。鉴于此,综述了路基结构性能的主要影响因素,并探讨了路基结构性能的衰变机理。结果表明:应力状态与路基湿度对路基结构性能影响最为显著,而路基性能衰变可从非饱和土基质吸力、抗剪强度及细颗粒土流失等方面进行解释。 展开更多
关键词 路基 路基湿度 回弹模量 永久变形 非饱和土土力学
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大型深基坑工程中“施工结构”的方案设计、实施与监测——兼谈基坑工程研究新进展
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作者 吕凤梧 刘前曦 +3 位作者 徐伟 伍朝琛 黄立雄 徐青松 《建筑施工》 1998年第2期4-7,共4页
基坑围护体兼作地下室外墙,同时可作载车和行人之用途,称谓“施工结构”。
关键词 基坑 监测 施工结构 扰动土土压力
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生长旺季花木如何移植
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作者 邹新群 《专业户》 2002年第9期14-14,共1页
早春晚秋温度低,花木处于休眠期,有些阔叶类花木叶子完全脱落,蒸腾量小,移植容易成活。但日常碰到新建、改建、扩建街区、景点、水利设施、道路、矿山、房产等,亟需在生长旺季搬迁或移植个体较大花木。生长旺季怎样移植花木才能取得满... 早春晚秋温度低,花木处于休眠期,有些阔叶类花木叶子完全脱落,蒸腾量小,移植容易成活。但日常碰到新建、改建、扩建街区、景点、水利设施、道路、矿山、房产等,亟需在生长旺季搬迁或移植个体较大花木。生长旺季怎样移植花木才能取得满意的成效呢? 展开更多
关键词 生长旺季 花木 移植 株势平衡 强度修剪 带母土土 浇水 遮荫 养护管理
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Column leaching process of rare earth and aluminum from weathered crust elution-deposited rare earth ore with ammonium salts 被引量:18
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作者 何正艳 张臻悦 +4 位作者 余军霞 徐志高 徐源来 周芳 池汝安 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第11期3024-3033,共10页
In order to better understand the leaching process of rare earth (RE) and aluminum (Al) from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the... In order to better understand the leaching process of rare earth (RE) and aluminum (Al) from the weathered crust elutiondepositedRE ore, the mass transfer of RE and Al in column leaching was investigated using the chromatographic plate theory. Theresults show that a higher initial ammonium concentration in a certain range can enhance the mass transfer process. pH of leachingagent in the range of 2 to 8 almost has no effect on the mass transfer efficiency of RE, but plays a positive role in the mass transferefficiency of Al under strong acidic condition (pH〈4). There is an optimum flow rate that makes the highest mass transfer efficiency.The optimum leaching condition of RE is the leaching agent pH of 4?8, ammonium concentration of 0.4 mol/L and flow rate of0.5 mL/min. The mass transfer efficiencies of RE and Al both follow the order: (NH4)2SO4〈NH4Cl〈NH4NO3, implying thecomplexing ability of anion. 展开更多
关键词 column leaching process weathered crust elution-deposited rare earth ore rare earth ALUMINUM ammonium salt MASSTRANSFER
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Effect of Protective Cultivation Patterns of Rice in Cold Areas on Soil Physiological and Biochemical Status in Paddy Field 被引量:8
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作者 汪秀志 钱永德 +4 位作者 张德远 刘崇文 刘丽华 吕艳东 郑桂萍 《Agricultural Science & Technology》 CAS 2010年第2期183-188,共6页
[Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil product... [Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil productivity of paddy field from the cultivation aspect.[Method] Taking kenjiandao 10 as the material,the variation laws of root weight,soil physical and chemical characteristics,soil enzyme,straw decomposition rate,soil temperature,microorganism of rice under the planting patterns of water-saving pro... 展开更多
关键词 Tillage methods Paddy field Soil physics and chemistry Soil microorganism Soil enzyme activity
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Analysis of Soil Degradation Causes in Orchards with Different Planting Years 被引量:5
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作者 王治国 付彦博 +3 位作者 饶晓娟 耿庆龙 孟阿静 冯耀祖 《Agricultural Science & Technology》 CAS 2014年第8期1331-1334,共4页
The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards... The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation. 展开更多
关键词 ORCHARD Soil degradation Soil available nutrient Trace element in soil
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Analysis for Soil Characteristics of Degraded Grassland on Alpine Meadow 被引量:10
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作者 杨元武 李希来 周华坤 《Agricultural Science & Technology》 CAS 2011年第8期1221-1225,共5页
[Objective]The aim of this study is to explore the effects of grassland degradation on soil physical and chemical properties.[Method]The ratio of plant root to soil and soil texture on Alpine Meadow were investigated ... [Objective]The aim of this study is to explore the effects of grassland degradation on soil physical and chemical properties.[Method]The ratio of plant root to soil and soil texture on Alpine Meadow were investigated in this study,and soil available N,P,K,Cu,Zn,organic matter and pH value were also analyzed by routine analysis of soil nutrients in different degraded grasslands.[Result]With the intensification of degraded gradient and the soil depth,the ratio of plant root to soil was decreased gradually.The highest ratio of plant root to soil was in 0-10 cm depth of soil in grassland with different degraded gradients,while its ratio of plant root to soil changed from 0.001 to 0.040 with soil type of loam.Soil chemical characteristic changed in different degraded gradients.The content of available N,P,K reduced significantly with the soil depth and the intensification of degraded gradients.The content of Cu and Zn was relatively lack in degraded grassland.[Conclusion]There is no significant correlation between nutrition content or pH value and the succession degree of degraded grassland. 展开更多
关键词 Alpine meadow Degraded grassland Ratio of plant root to soil Soil texture Chemical characteristics
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Effects of Nitrogen Treatments on Organic Carbon Mineralization of Citrus Orchard Soil 被引量:2
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作者 翁伯琦 王峰 +4 位作者 王义祥 江福英 吴志丹 尤志明 张文锦 《Agricultural Science & Technology》 CAS 2012年第8期1702-1707,共6页
[Objective] This study aimed to investigate the effect of soil organic carbon mineralization at different temperature on the amount of nitrogen application, in order to provide references for the establishment of carb... [Objective] This study aimed to investigate the effect of soil organic carbon mineralization at different temperature on the amount of nitrogen application, in order to provide references for the establishment of carbon circulation model for orchard eco-system. [Method] The effects of nitrogen treatments on soil organic carbon mineralization of citrus orchard soil were investigated under 10, 20, 30 ℃ by laboratory simulated experiment. [Result] The mineralization rate decreased quickly at the be- ginning of the experiment but remained stable at the late period under three temper- ature treatments. The amounts of CO2 ranged from 1 328.25-2 219.42 mg/kg under three temperature condition, and the amount of soil organic carbon mineralization of 100 mg/kg (N4) treatment was the greatest, while that of CK was the lowest. High level nitrogen treatment (N4 and N3) were significant higher than the lower level nitro- gen treatment (N2 and N1). The soil organic carbon mineralization rate increased with the temperature from 10 to 30℃. The dependence of soil carbon mineralization to temperature (Q10) was different under different nitrogen treatments that the Qlo value of N2 treatment was the lowest while that of the N4 treatment was the greatest. The soil organic carbon mineralization in Citrus orange orchard soil was affected significantly by high level nitrogen treatment, but with no significance under lower nitrogen treatment. [Conclusion] The dependence of soil carbon mineralization to temperature (Q10) increased with the increasing nitrogen input. The combination of nitrogen with temperature may increase the CO2 emission from Citrus orchard soil. 展开更多
关键词 Citrus orchard Soil organic carbon mineralization Nitrogen treatment TEMPERATURE
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Effects of Long-term Located Fertilization on Wheat Yield and Soil Nutrients of Three Types of Soils in Shandong Province 被引量:1
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作者 张英鹏 刘兆辉 +3 位作者 李彦 仲子文 孙明 井永苹 《Agricultural Science & Technology》 CAS 2014年第3期400-406,426,共8页
[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experi... [Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experiment in Jinan of Shandong Province was selected and the results of soil nutrient and crop yield in 1984, 1987, 1988, 1989, 1990, 2001, 2005, 2006, 2007 and 2010 were measured and collected. In this study, five treatments: CK, NP, NK, PK and NPK of the located experiment were selected. [Result] The three types of soils in wheat yields decreased signifi- cantly in the first several years and in 2006. Wheat yields of the treatments with P fertilizers were obviously higher than those without P fertilizers; it was shown that phosphorus is the primary nutritional factor for high-yielding of wheat. The highest yield is from cinnamon soil, followed by that from brown soil, and the lowest pro- duction is from fluvo-aquic soil. Under the same fertilization, the influence of other factors on wheat yield of brown soil is the smallest, while cinnamon soil is vulnera- ble to the influence of external conditions, resulting in larger fluctuation of annual wheat yield. The alkali-hydro nitrogen contents of three kinds of soils first de- creased, then raised, and at last reduced apparently. Since 2007, the change of al- kali-hydro nitrogen content appeared rebounded. The available P contents of no- phosphorus treatments decreased over time while those of the treatments with P fertilizers increased at first, then decreased, and after that kept relatively stable. The available K contents of no K treatments decreased slowly. The treatments of PK and NK had higher available K content than NPK treatment. [Conclusion] Thus, it is an effective fertilization measure to improve the wheat yield by supplying reasonable phosphate fertilizer and nitrogen fertilizer and making up potassium fertilizer. 展开更多
关键词 Long-term located fertilization Brown soil Fluvo-aquic soil Cinnamon soil Wheat yield Soil nutrient
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Soil structure characters of different soil and water conservation plantations in typical black soil region 被引量:1
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作者 史长婷 王恩姮 +1 位作者 谷会岩 陈祥伟 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第2期151-154,I0004,共5页
A study was conducted to determine the characters of soil structure in different water and soil conservation forests in Keshan County,northwest of Heilongjiang Province,China.The soil bulk density,the ratio of non-cap... A study was conducted to determine the characters of soil structure in different water and soil conservation forests in Keshan County,northwest of Heilongjiang Province,China.The soil bulk density,the ratio of non-capillary porosity and capillary porosity(NCP/CP),and the generalized soil structure index(GSSI) were measured for Fraxinus mandshurica,Larix gmelini,Pinus sylvestris var.mongolica,and Picea koraiensis plantations as well as the abandoned land(as control) adjacent to the forests in typical black soil region.Results show that at soil depth of 0–30cm,the soil bulk density of F.mandshurica forest and L.gmelini forest was lower than that of P.sylvestris var.mongolica forest and P.koraiensis forest,with the relative decrease of 8.04%–11.01%.The soil bulk density of L.gmelini forest was significantly different from that of the P.sylvestris var.mongolica forest and P.koraiensis forest.The NCP/CP values of the four types of plantations were all higher(59.75%–128.82% relatively) than that of abandoned land(p〈0.05),indicating that the soil aeration and permeability under forest were enhanced,especially under L.gmelini forest.GSSI values of the four types of forests were also relatively higher(2.98%–4.36%) than abandoned land(p〈0.05),indicating that those soil and water conservation forests,especially the F.mandshurica forest and P.koraiensis forest,can promote soil condition to approximate ideal soil structure.The result of this study can provide theoretical basis for scientifically evaluating the effects of vegetation restoration on soil quality in typical black soil region. 展开更多
关键词 typical black soil soil and water conservation plantation Bulk density GSSI NCP/CP
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Some factors controlling diffusive transportof potassium ion through clayey soils 被引量:3
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作者 杜延军 刘松玉 林重德 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期106-111,共6页
To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer ... To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer program Pollute V6.3, the effective diffusion coefficients of K^+ of the soils were back-calculated from the diffusion tests. It is found that the Ariake clay has a larger effective diffusion coefficient than the Akaboku soil, indicating that the Ariake clay may provide a better diffusion barrier. A comparison of the effective diffusion coefficients between the single-salt solution condition and the multi-salt solution condition indicates that soils have higher effective diffusion coefficients under the former condition. It is suggested to use miscible solution close to landfill leachates for determining effective diffusion coefficients of specified chemical species for a practical design. 展开更多
关键词 adsorption Ariake clay BARRIER batch-type test CONTAMINANT diffusion LANDFILL
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Seasonal changes of soil respiration in Betula platyphylla forest in Changbai Mountain, China 被引量:2
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作者 刘颖 韩士杰 林鹿 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第4期367-371,I0007,共6页
A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004.... A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004. Results indicated that the total soil respiration, root-severed soil respiration and the root respiration followed a similar seasonal trend, with a high rate in summer due to wet and high temperature and a low rate in spring and autumn due to lower temperature. The mean rates of total soil respiration, root-severed soil respiration and root respiration were 4.44, 2.30 and 2.14 μmol.m^-2.s^-1, respectively during the growing season, and they were all exponentially correlated with temperature. Soil respiration rate had a linear correlation with soil volumetric moisture. The Q10 values for total soil respiration, root-severed soil respiration and root respiration were 2,82, 2.59 and 3. 16, respectively. The contribution rate of root respiration to the total soil respiration was between 29.3% and 58.7% during the growing season, indicating that root is a major component of soil respiration. The annual mean rates of total soil respiration, root-severed soil respiration and root respiration were 1.96, 1.08, and 0.87 μmol.m^-2.s^-1, or 741.73 408.71, and 329.24 g.m^-2.a^-1, respectively. Root respiration contributed 44.4% to the annual total soil respiration. The relationship proposed for soil respiration with soil lemperature was useful for understanding and predicting potential changes in Changbai Mountain B. platyphylla forest ecosystem in response to forest management and climate change. 展开更多
关键词 root respiration seasonal variations soil respiration soil temperature soil water content
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Spatial pattern of soil carbon and nutrient storage at the Alpine tun-dra ecosystem of Changbai Mountain, China 被引量:3
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作者 魏晶 吴钢 +1 位作者 邓红兵 赵景柱 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第4期249-254,共6页
In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different... In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different depths were significantly (p<0.05) higher in Meadow alpine tundra vegetation than that in other vegetation types; the soil C (including inorganic carbon) concentrations at layer below 10 cm are significantly (p<0.05) higher than at layer of 1020 cm among the different vegetation types; the spatial distribution of soil N concentration at top surface of 0-10 cm depth was similar to that at 1020 cm; the soil P concentrations at different depths were significantly (p<0.05) lower at Lithic alpine tundra vegetation than that at other vegetation types; soil K concentration was significantly (p<0.05) higher in Felsenmeer alpine tundra vegetation and Lithic alpine tundra vegetation than that in Typical alpine tundra, Meadow alpine tundra, and Swamp alpine tundra vegetations.. However, the soil K had not significant change at different soil depths of each vegetation type. Soil S concentration was dramatically higher in Meadow alpine tundra vegetation than that in other vegetation types. For each vegetation type, the ratios of C: N, C: P, C: K and C: S generally decreased with soil depth. The ratio of C: N was significantly higher at 010 cm than that at 1020 cm for all vegetation types except at the top layer of the Swamp alpine tundra vegetation. Our study showed that soil C and nutrients storage were significantly spatial heterogeneity. 展开更多
关键词 Soil carbon storage Soil nutrients Alpine tundra ecosystem Vegetation type Changbai Mountain
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