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Temporal changes in mixing effects on litter decay and nitrogen release in a boreal riparian forest in northeastern China

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Journal of Forestry Research 2024年第2期35卷 33-41页

作者： Simin Wang Bo Liu Rui Li xiaoxin sun Rong Mao Key Laboratory of National Forestry and Grassland Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang 330045People’s Republic of China Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102People’s Republic of China Key Laboratory of Sustainable Forest Ecosystem Management of Ministry of Education School of ForestryNortheast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang Sanjiang Plain Wetland Ecosystem Research Station Fuyuan 156500People’s Republic of China

In riparian forests,litter decay provides essential energy and nutrients for both terrestrial and fluvial *** mixing effects(LMEs)are crucial in regulating litter decay and nutrient dynamics,yet how LMEs change over time is unclear in riparian *** this study,leaf litter of three common species(Alnus sibirica *** Turcz,Betula platyphylla Sukaczev,and Betula fruticosa Pall.)were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen(N)remaining in whole litter mixtures over a 3-year period in a boreal riparian forest,northeastern *** were also assessed for component litter mass and N remaining by separating litter mixtures by *** the decay of litter mixtures,antagonistic effects on mass and N remaining were dominant after one and two years of decay,whereas only additive effects were observed after three *** correlated negatively with functional diversity after the first and two years of decay but disappeared after three *** sorting litter mixtures by species,non-additive LMEs on mass and N remaining decreased over incubation ***,non-additive LMEs were more frequent for litter of both *** and *** with lower N concentration than for *** litter with higher N *** results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests.

关键词： Biodiversity Litter quality Litter mixtures Synergistic effects Functional diversity

Non-use value assessment for wetland ecosystem service of Hongxing National Nature Reserve in northeast China

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Journal of Forestry Research 2016年第6期27卷 1435-1442页

作者： Xin Jin Jianzhang Ma Tijiu Cai xiaoxin sun Northeast Forestry University Harbin 150040People's Republic of China

By the contingent value method, we studied the non-use value of wetland ecosystem service of Hongxing National Nature Reserve （HNNR） in Heilongjiang Pro- vince, northeast China. The proportion of respondents willing to pay （WTP） for protection of HNNR was 63 %. The WTP ratio was affected by geographical area, contact nature, personal preferences, and familiar degree of the respondents. The WTP value was affected by age, education level and career of the respondents. The mainly reasons for people rejecting to pay for protecting HNNR were ＂I am not familiar to HNNR＂ and ＂I had no capacity for additional spending because of low income＂. Weighted average individual WTP value was CNY 59.26 Yuan ind.^-1 year^-1 for all the respondents with WTP. The total non-use ecosystem service value of HNNR was CNY 1430 million Yuan in 2013. The heritage value was highest followed by existence value and option value. From the high ecosystem service value in HNNR, it is very important to construct nature reserve for protecting natural ecosystems and human sustainable use of natural resources.

关键词： Ecosystem service Non-use value Hongxing National Nature Reserve - xiaoxing'an Mountains

Adjustable contrast optical target device for test of acquisition of photoelectric theodolite

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Science China(Technological Sciences) 2013年第8期56卷 2052-2058页

作者： sun xiaoxin SHEN XiangHeng WANG SuHua YE Lu School of Computer Science and Information Technology Northeast Normal University Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences School of Information Technology Changchun Vocational Institute of Technology

A new device used to detect the low contrast target acquisition of photoelectric theodolite is designed and its reliability is experimentally *** adjustable contrast optical target device,which can simulate the sky background luminance and a low contrast target,is *** utilizes a big integrating sphere and a small one to simulate the luminance of the background and target ***,by controlling the luminous flux of the two integrating spheres,the targets and background radiance can be continuously adjustable under the condition of constant color ***,the contrast can be controlled continuously in the range of 0%-90% and its stability is better than 1%.The biggest background luminance exceeds 60 W m-2str-1 in the spectral range of 400-800 nm.

关键词： photoelectric theodolite adjustable contrast integration sphere collimating lens

Changes of plant species diversity and biomass with reclaimed marshes restoration

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Journal of Forestry Research 2021年第1期32卷 133-142页

作者： Xin Jin xiaoxin sun Haixing Li Danhui Zhao Dong Li Lei Wang Xiuling Man Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China Heilongjiang Sanjiang Plain Wetland Ecosystem Research Station Fuyuan 156500People’s Republic of China Panjin Institute of Wetland Science Panjin 124000People’s Republic of China School of Geography and Environmental Science Guizhou Normal UniversityGuiyang 550025People’s Republic of China

Wetland restoration had been implemented for more than two decades in Sanjiang Plain,Northeast *** assess the restoration effi ciency of wetland vegetation,we investigated plants composition of community,plant species diversity and aboveground biomass of restored sites in a chronosequence of restoration(1,2,3,6,8,11,15 and 25 years)in the Sanjiang Nature *** comparison,we also investigated the same factors in a cropland and a natural marsh adjacent to the restored *** results showed that wetland plant species can invade quickly after croplands were abandoned when there were suitable hydrology *** the early stage of the restoration,weeds were main plant species in the restored *** species appeared at the same time but diff ered from the dominant species from the adjacent natural *** native wetland species could dominance the community after 3-year *** richness and diversity increased on the early stage,and then decreased to the similar level of the natural marsh with the extension of *** biomass could restore easier than the species composition and *** results indicated that plant species composition and diversity of abandoned reclaimed wetlands can restore gradually by natural succession in Sanjiang ***,25-year restoration site had similarity index of only 56%with the natural marsh,which revealed that two decades are not enough for complete restoration of vegetation.

关键词： Plant species composition Richness index Shannon–Wiener index Similarity index Wetland restoration

Interaction between Hosts and Guests of Rural Tourism in Northeast China Based on Symbolic Interaction Theory

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Asian Agricultural Research 2018年第1期10卷 73-75页

作者： Shuheng XU xiaoxin sun Yingchun HU School of Business Administration University of Science and Technology Liaoning

With constant economic development and continuous improvement of living standards in Northeast China,rural tourism,as a new type of tourism,is increasingly favored. From the perspective of symbolic interaction theory,taking the current situation of rural tourism in Northeast China as an example,this paper explained the semiotic significance between hosts and guests in rural tourism. It established the evaluation indicators for authentic symbolic perception of rural tourism. Also,combined with the theories of sociology and anthropology,it studied the interaction between hosts and tourists of rural tourism in Northeast China.

关键词： Rural tourism in Northeast China Interaction between hosts and guests Symbolic interaction theory

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幼儿园教师职业嵌入的场动力模型研究

教育研究与实验 2024年第5期 137-148页

作者：但菲孙小鑫沈阳师范大学学前与初等教育学院沈阳110034 中国航天科技集团有限公司第一研究院航天幼儿园北京100071

幼儿园教师流失率高、流动性强是学前教师高质量发展的瓶颈。为更好地保障学前师资力量稳定性,基于勒温的场动力论构建幼儿园教师职业嵌入的场动力模型,运用访谈法、问卷法编制幼儿园教师职业嵌入的本土化测量工具,探寻幼儿园教师的“... 详细信息

幼儿园教师流失率高、流动性强是学前教师高质量发展的瓶颈。为更好地保障学前师资力量稳定性,基于勒温的场动力论构建幼儿园教师职业嵌入的场动力模型,运用访谈法、问卷法编制幼儿园教师职业嵌入的本土化测量工具,探寻幼儿园教师的“个体场”与“环境场”如何相互作用并共同为幼儿园教师职业嵌入提供动力。研究发现,幼儿园教师“个人场”中教师主体因素对职业联系、职业牺牲、职业匹配具有显著正向影响;幼儿园教师“环境场”中的园所组织因素和社会行业因素对职业联系、职业牺牲具有显著正向影响。基于此,从巩固调适“个人场”和共建发展“环境场”两方面提出促进幼儿园教师职业嵌入的有效策略。

关键词：幼儿园教师职业嵌入场动力论

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江苏省城镇化与农业产业化协调发展格局研究

地域研究与开发 2017年第1期36卷 12-17页

作者：孙晓欣马晓冬江苏师范大学地理测绘与城乡规划学院江苏徐州221116 江苏师范大学区域与城市研究中心江苏徐州220009

通过构建城镇化与农业产业化发展综合评价指标体系,采用熵值法、模比系数、耦合协同度模型等方法,揭示江苏省55个县(市)的城镇化与农业产业化发展的格局特征,并探究两者耦合协调发展特征。结果发现:1)江苏省城镇化与农业产业化水平均呈... 详细信息

通过构建城镇化与农业产业化发展综合评价指标体系,采用熵值法、模比系数、耦合协同度模型等方法,揭示江苏省55个县(市)的城镇化与农业产业化发展的格局特征,并探究两者耦合协调发展特征。结果发现:1)江苏省城镇化与农业产业化水平均呈现出较大的地域差异,"两化"高低水平的空间分布并不完全吻合,城镇化发展内部差异总体上大于农业产业化差异;2)"两化"耦合度与协同度空间分布差异明显,耦合度与协同度高低值的空间分布差异也较大,但整体协同水平不高;3)基于城镇化和农业产业化水平及其耦合协同度的分数特征,将江苏省划分为4种协调发展的地域类型,并分析其相应成因及发展对策,为江苏省推进"两化"协调互动提供决策依据。

关键词：城镇化农业产业化耦合协同度协调发展江苏省

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聚醚砜的功能化改性及其性能

化学反应工程与工艺 2018年第3期34卷 276-281,288页

作者：孙小欣李毓陵王洪东华大学纺织面料技术教育部重点实验室上海201620

聚醚砜(PES)是一种带有苯环的高分子材料,比较容易进行功能改性。以1,4-二氯甲氧基丁烷为氯甲基化试剂,N-甲基咪唑为季铵化试剂,对PES进行季铵化改性,使其成为一种表面带有电荷的功能材料。采用红外光谱和核磁氢谱分析表征了PES的氯甲... 详细信息

聚醚砜(PES)是一种带有苯环的高分子材料,比较容易进行功能改性。以1,4-二氯甲氧基丁烷为氯甲基化试剂,N-甲基咪唑为季铵化试剂,对PES进行季铵化改性,使其成为一种表面带有电荷的功能材料。采用红外光谱和核磁氢谱分析表征了PES的氯甲基化和季铵化程度,并测试了样品Zeta电位、静电荷、离子交换量和接触角等性能。结果表明,季铵化聚醚砜膜的离子交换量、静电荷和Zeta电位值皆与季铵化程度呈正相关关系,季铵化改性可以明显提高聚醚砜的亲水性。

关键词：聚醚砜季铵化 Zeta 电位

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顺层岩质滑坡渐进破坏进入加速的能量学判据

地球科学 2021年第11期46卷 4033-4042页

作者：唐朝晖余小龙柴波张淑杞孙晓鑫中国地质大学工程学院湖北武汉430074 中国地质大学环境学院湖北武汉430078 西南能矿建设工程有限公司贵州贵阳550022

顺层岩质滑坡是最常见的斜坡灾害,研究其渐进破坏过程、建立预报判据对于防灾减灾具有重要意义.以秭归杉树槽滑坡为例,在野外调查和室内岩石试验的基础上,利用JRC-JCS模型及GSI法估算得出滑坡基本力学参数;通过FLAC^(3D)模拟滑坡渐进破... 详细信息

顺层岩质滑坡是最常见的斜坡灾害,研究其渐进破坏过程、建立预报判据对于防灾减灾具有重要意义.以秭归杉树槽滑坡为例,在野外调查和室内岩石试验的基础上,利用JRC-JCS模型及GSI法估算得出滑坡基本力学参数;通过FLAC^(3D)模拟滑坡渐进破坏过程,分析顺层岩质滑坡变形破坏的发展规律;基于能量守恒和虚功原理,提出了顺层岩质滑坡迈入加速变形的能量学判据.研究表明:杉树槽滑坡由后缘向前渐进破坏,后缘变形累积的总位移值不断增大,前缘切层段的锁固作用使变形迅速降低,当临近破坏时,前缘位移由前向后发展,滑面快速贯通;滑体沿滑动方向应变曲线可近似表示为"S"型曲线,随渐进破坏该曲线向坡下发展;以滑体动能增量大于0作为滑坡迈入加速变形的能量学判据,其结果符合滑坡地质演化观点,与FLAC^(3D)模拟结果吻合.

关键词：顺层岩质滑坡预测预报数值模拟能量学判据工程地质