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Small-Scale Spatial Variability of Soil Nutrients and Vegetation Properties in Semi-Arid Northern China

Pedosphere 2006年第6期16卷 778-787页

作者： chen fu-sheng ZENG De-Hui HE Xing-Yuan Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shengyang 110016 （China） Life College Nanchang University Nanchang 330047 （China）

A field experiment was conducted at Kezuohouqi County, Inner Mongolia Autonomous Region of China, which was located on the southeastern edge of the Horqin Sandy Land, to study the spatial variability of soil nutrients for a smallscale, nutrient-poor, sandy site in a semi-arid region of northern China; to investigate whether or not there were 'islands of fertility' at the experimental site; and to determine the key nutrient elements that sustained ecosystem stability. Results obtained from geostatistical analysis indicated that the spatial distribution pattern of soil total nitrogen (STN) was far different from those of soil organic matter (SOM), total phosphorus (STP), and total potassium (STK). Compared to SOM, STP, and STK, STN had a lower structural heterogeneity ratio and a longer range, while other elements were all similar. In addition, STN had an isotropic spatial structure, whereas the others had an anisotropic spatial structure. The spatial structure patterns of herbage species, cover,and height also differed, indicating that spatial variability was subjected to different ecological factors. Differences in the spatial variability patterns among soil nutrients and vegetation properties showed that soil nutrients for a small-scale were not the primary limiting factors that influenced herbage spatial distribution patterns. Incorporating spatial distribution patterns of tree species, namely, Pinus sylvestris var. mongolica Litv. and shrub Lespedeza bicolor Turcz. in a research plot and using fractal dimension,SOM, STP, and STK were shown to contribute to the 'islands of fertility' phenomenon, however STN was not, possibly meaning that nitrogen was a key limiting element. Therefore, during restoration of similar ecosystems more attention should be given to soil nitrogen.

关键词： Pinus sylvestris war. mongolica Litv. semi-arid region soil nutrients spatial variability species richness

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Soil Inorganic Nitrogen and Microbial Biomass Carbon and Nitrogen Under Pine Plantations in Zhanggutai Sandy Soil

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Pedosphere 2008年第6期18卷 775-784页

作者： YU Zhan-Yuan chen fu-sheng ZENG De-Hui ZHAO Qiong chen Guang-sheng Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 （China）. Life College Nanchang University Nanchang 330029 （China） Ecosystem Sciences and Regional Analysis （ESRA） Lab. School of Forestry ＆Wildlife Science Auburn University Alabama 36849 （USA）

The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004 by the in situ closed-top core incubation method. All mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 40.0-128.9, and 5.4-15.2 μg g^-1, respectively. The average contents of soil NH4^＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4^＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.

关键词： ecosystem management Horqin sandy land soil nitrogen availability Pinus densiflora Pinus sylvestris vat. mongoliea

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Soil nitrogen transformations varied with plant community under Nanchang urban forests in mid-subtropical zone of China

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Journal of Forestry Research 2011年第4期22卷 569-576页

作者： REN Wen chen fu-sheng HU Xiao-fei YU Ming-quan FENG Xue College of Life Sciences Nanehang University Nanchang 330031 China College of Life Sciences Jiangxi Science ＆ Technology Normal University Nanchang 330038 P. R. China

Soil N transformations using the polyvinyl chloride （PVC） closed-top tube in situ incubation method were studied in Nanchang urban forests of the mid-subtropical region of China in different months of 2007. Four plots of 20 m × 20 m were established in four different plant communities that represented typical successional stages of forest development including shrubs, coniferous forest, mixed forest and broad- leaved forest. Average concentrations of soil NH4^＋-N from January to December were not different among the four plant communities. The concentrations of soil NO3^--N and mineral N, and the annual rotes of ammonification, nitrification and net N-mineralization under the early successional shrub community and coniferous forest were generally lower than that of the late successional mixed and broad-leaved forests （p〈0.05）. Similar differences among the plant communities were also shown in the relative nitrification index （NH4^＋-N/NO3^--N） and relative nitrification intensity （nitrification rate/net N-mineralization rate）. The annual net N-mineralization rate was increased from younger to older plant communities, from 15.1 and 41.4 ***^-1.a^-1 under the shrubs and coniferous forest communities to 98.0 and 112.9 ***^-1.a^-1 under the mixed and broad-leaved forests, respectively. Moreover, the high annual nitrification rates （50-70 ***^-1.a^-1） and its end product, NO3-N （2.4-3.8 mg·kg^-1）, under older plant communities could increase the potential risk of N loss. Additionally, the temporal patterns of the different soil N variables mentioned above varied with different plant community due to the combined affects of natural biological processes associated with forest maturation and urbanization. Our results indicated that urban forests are moving towards a state of＂N saturation＂（extremely niUification rate and NO3^--N content） as they mature.

关键词： global change nitrogen saturation soil nitrogen mineralization Southern China urban forests

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Soil animals and nitrogen mineralization under sand-fixation plantations in Zhanggutai region,China

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Journal of Forestry Research 2007年第1期18卷 73-77页

作者： chen fu-sheng ZENG De-hui HU Xiao-fei chen Guang-sheng YU Zhan-yuan Daqinggou Ecological Station Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 P. R. China College of Life Sciences Nanchang University Nanchang 330031 P. R. China Ecosystem Sciences ＆ Regional Analysis Laboratory School of Forestry and Wildlife Sciences Auburn University AL 36830 USA

The effects of soil animals on soil nitrogen (N) mineralization and its availability were studied by investigating soil animal groups and their amounts of macro-faunas sorted by hand, and middle and microfaunas distinguished with Tullgren and Baermann methods under three Pinus sylvestris var. mongolica Litv. plantations in Zhanggutai sandy land, China. In addition, soil N mineralization rate was also measured with PVC closed-top tube in situ incubation method. The soil animals collected during growing season belonged to 13 orders, 5 groups, 4 phyla, whose average density was 86 249.17 individuals·m^(-2). There were significant differences in soil animal species, densities, diversities and evenness among three plantations. Permanent grazing resulted in decrease of soil animal species and diversity. The average ammonification, nitrification and mineralization rates were 0.48 g·m^(-2)·a^(-1), 3.68 g·m^(-2)·a^(-1) and 4.16 g·m^(-2)·a^(-1), respectively. The ammonification rate in near-mature forest was higher than that in middle-age forests, while the order of nitrification and net mineralization rates was: middle-age forest without grazing < middle-age forest with grazing < near-mature forest with grazing (P<0.05). Soil N mineralization rate increased with soil animal amounts, but no significant relationship with diversity. The contribution of soil animals to N mineralization was different for different ecosystems due to influences of complex factors including grazing, soil characteristics, the quality and amount of litter on N mineralization.

关键词： Soil animals N mineralization Pinus sylvestris var. mongolica Litv. Zhanggutai sandy land

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Observation of atomic steps on CaCO_3 crystal surface

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Nuclear Science and Techniques 1998年第2期9卷 90-91页

作者： Sun Jie-Lin Hu Jun Zhang Yi chen sheng-fu Ouyang Zhen-Qian and Li Min-Qian (Shanghai Institute of Nuclear Research, the Chinese Academy of Sciences, Shanghai 201800 ) Shangfiai Institute of Nuclear Research Chinese Academy of Sciences Slianghai 201800 China

By using scanning polarization force microscopy,the deliquescence process and the atomic steps on the cleavage surface of CaCO3 in air were studied in *** an exposure to medium umidity(-57%),the sloiw step movement ha... 详细信息

关键词： CaCO3晶体表面原子阶跃观测

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An Improved Heuristic Recursive Strategy Based on Genetic Algorithm for the Strip Rectangular Packing Problem

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自动化学报 2007年第9期33卷 911-916页

作者： ZHANG De-fu chen sheng-Da LIU Yan-Juan Department of Computer Science Xiamen University Xiamen 361005 P. Ft. China

与基因算法结合的改进启发式的递归的策略在这份报纸被介绍。第一，这个方法寻找一些矩形，它有一样的长度或宽度，到没有浪费空间，形成一些层，然后，计算留下包装顺序的高度使用启发式的递归的策略并且使用基因算法的进化能力减少高... 详细信息

与基因算法结合的改进启发式的递归的策略在这份报纸被介绍。第一，这个方法寻找一些矩形，它有一样的长度或宽度，到没有浪费空间，形成一些层，然后，计算留下包装顺序的高度使用启发式的递归的策略并且使用基因算法的进化能力减少高度。基准问题的几个班上的计算结果证明了介绍算法能与已知的进化启发规则竞争。它特别为大测试问题更好表现。

关键词：改良式启发式递归策略遗传算法矩形封装

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一种新的正规自适应边缘保护的超分辨率算法(英文)

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红外与毫米波学报 2014年第1期33卷 98-105页

作者：余徽陈福胜张智杰王晨晟华中科技大学光学与电子信息学院湖北武汉430074 华中光电技术研究所-武汉光电国家实验室湖北武汉430074

主要提出了一个新的正规自适应超分辨率算法.正规项只惩罚图像中可能包含有大量噪声的低频部分,同时保护图像中可能包含有锐利边缘的高频部分,其中,惩罚阈值自动地被一个线性函数决定.对于正规参数的选择,这里不采用固定的正规参数而是... 详细信息

主要提出了一个新的正规自适应超分辨率算法.正规项只惩罚图像中可能包含有大量噪声的低频部分,同时保护图像中可能包含有锐利边缘的高频部分,其中,惩罚阈值自动地被一个线性函数决定.对于正规参数的选择,这里不采用固定的正规参数而是提出一个对数函数在每次迭代时自适应地选择正规参数.该算法经过仿真实验和真实的红外图像测试,实验结果显示该算法鲁棒性好,可以有效复原图像细节.

关键词：超分辨率正规项正规参数惩罚阈值

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ZL208铝合金端盖熔模铸造工艺设计

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铸造 2020年第3期69卷 297-300页

作者：陈复生新乡市航空锻铸有限公司河南新乡453049

某航空气压调节器端盖采用ZL208铝合金,经熔模铸造硅溶胶制壳工艺生产而成。通过设计合理的浇注系统、硅溶胶制壳工艺,并采用蒸汽脱蜡及合适的焙烧工艺、熔炼浇注工艺、热处理工艺,获得了尺寸精度高、内部质量好的铸件,产品合格率达到85... 详细信息

某航空气压调节器端盖采用ZL208铝合金,经熔模铸造硅溶胶制壳工艺生产而成。通过设计合理的浇注系统、硅溶胶制壳工艺,并采用蒸汽脱蜡及合适的焙烧工艺、熔炼浇注工艺、热处理工艺,获得了尺寸精度高、内部质量好的铸件,产品合格率达到85%以上。该工艺方法不仅操作简单,且制壳时对环境无污染,应用较为广泛。

关键词： ZL208合金浇注系统硅溶胶制壳熔炼浇注工艺热处理工艺

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耕种对沙地土壤全磷空间变异性的影响

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中国环境科学 2005年第B6期25卷 85-88页

作者：陈伏生曾德慧中国科学院沈阳应用生态研究所

利用经典统计学和地统计学相结合的方法,以科尔沁沙地东南缘的丘间低地为例,分析了农业耕种对沙地土壤全磷空间变异性的影响.结果表明,草地开垦8年后的耕地同未开垦的草地相比,表层和亚表层土壤全磷量均有明显增加(P<0.05);两层土壤全... 详细信息

利用经典统计学和地统计学相结合的方法,以科尔沁沙地东南缘的丘间低地为例,分析了农业耕种对沙地土壤全磷空间变异性的影响.结果表明,草地开垦8年后的耕地同未开垦的草地相比,表层和亚表层土壤全磷量均有明显增加(P<0.05);两层土壤全磷贮量增加7.64%,约增加25.71kg/hm2.耕地同草地相比,土壤全磷空间结构和格局存在明显差异.耕地表层表现为一种随机上下波动的空间分布格局,而草地表现为相对均一的空间分布格局.亚表层耕地同草地相比,基台值、结构方差和变程明显偏大,结构异质性和空间依赖性较强,而随机性较弱的空间分布格局.分数维进一步说明耕地与草地土壤全磷空间变异性的差异.克立格制图直观地反映2种土地利用方式下土壤全磷的空间结构特征.为此,认为耕种易导致沙地土壤退化,退耕还草有利于维持脆弱沙地生态系统的稳定性.

关键词：科尔沁沙地土壤全磷农业耕种空间变异性地统计学

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Supplement to New Words and Expressions

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福建外语 1986年第2期 7-11页

作者：陈福生

New words and expressions I havementioned in my previous article(见《福建外语》1984年4期)are supple-mented and amplified with the follow-ing:*** capital put on festive air(首

关键词：土办法 Supplement to New Words and Expressions 缓和

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