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Combined effects of snow depth and nitrogen addition on ephemeral growth at the southern edge of the Gurbantunggut Desert,China

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Journal of Arid Land 2013年第4期5卷 500-510页

作者： lianlian fan Yan LI LiSong TANG Jian MA State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences University of Chinese Academy of Sciences

Water and nitrogen （N） inputs are considered as the two main limiting factors affecting plant *** in these inputs are expected to alter the structure and composition of the plant community,thereby influencing biodiversity and ecosystem *** is a form of precipitation in winter,and snow melting can recharge soil water and result in a flourish of ephemerals during springtime in the Gurbantunggut Desert,China.A bi-factor experiment was designed and deployed during the snow-covering season from 2009 to *** experiment aimed to explore the effects of different snow-covering depths and N addition levels on *** indicated that deeper snow cover led to the increases in water content in topsoil as well as density and coverage of ephemeral plants in the same N treatment; by contrast,N addition sharply decreased the density of ephemerals in the same snow ***,N addition exhibited a different effect on the growth of ephemeral plants：in the 50％ snow treatment,N addition limited the growth of ephemeral plants,showing that the height and the aboveground biomass of the ephemeral plants were lower than in those without N addition; while with the increases in snow depth （100％ and 150％ snow treatments）,N addition benefited the growth of the dominant individual *** richness was not significantly affected by snow in the same N ***,N addition significantly decreased the species richness in the same snow-covering *** primary productivity of ephemerals in the N addition increased with the increase of snow *** variations indicated that the effect of N on the growth of ephemerals was restricted by water *** plenty of water （100％ and 150％ snow treatments）,N addition contributed to the growth of ephemeral plants; while with less water （50％ snow treatment）,N addition restricted the growth of ephemeral plants.

关键词： snow depth soil water content N addition ephemeral plant plant density species richness

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Ecological biomass allocation strategies in plant species with different life forms in a cold desert, China

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Journal of Arid Land 2019年第5期11卷 729-739页

作者： fan lianlian DING Junxiang MA Xuexi LI Yaoming Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China Fukang Station of Desert Ecology Chinese Academy of SciencesFukang 8315005China Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041China

Biomass allocation patterns among plant species are related to their adaptive ecological strategies. Ephemeral, ephemeroid and annual plant life forms represent three typical growth strategies of plants that grow in autumn and early spring in the cold deserts of China. These plants play an important role in reducing wind velocity in the desert areas. However, despite numerous studies, the strategies of biomass allocation among plant species with these three life forms remain contentious. In this study, we conducted a preliminary quadrat study during 2014–2016 in the southern part of the Gurbantunggut Desert, China, to investigate the allocation patterns of above-ground biomass(AGB) and below-ground biomass(BGB) at the individual level in 17 ephemeral, 3 ephemeroid and 4 annual plant species. Since ephemeral plants can germinate in autumn, we also compared biomass allocation patterns between plants that germinated in autumn 2015 and spring 2016 for 4 common ephemeral species. The healthy mature individual plants of each species were sampled and the AGB, BGB, total biomass(TB), leaf mass ratio(LMR) and root/shoot ratio(R/S) were calculated for 201 sample quadrats in the study area. We also studied the relationships between AGB and BGB of plants with the three different life forms(ephemeral, ephemeroid and annual). The mean AGB values of ephemeral, ephemeroid and annual plants were 0.806, 3.759 and 1.546 g/plant, respectively, and the mean BGB values were 0.106, 4.996 and 0.166 g/plant, respectively. The mean R/S value was significantly higher in ephemeroid plants(1.675) than in ephemeral(0.154) and annual(0.147) plants. The mean LMR was the highest in annual plants, followed by ephemeroid plants and ephemeral plants, reflecting the fact that annual plants allocate more biomass to leaves, associated with their longer life span. Biomass of ephemeral plants that germinated in autumn was significantly higher than those of corresponding plants that germinated in spring in

关键词： above-ground biomass below-ground biomass plant life forms herbaceous species allometric hypothesis isometric hypothesis Gurbantunggut Desert

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Spatial heterogeneity of soil chemical properties between Haloxylon persicum and Haloxylon ammodendron populations

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Journal of Arid Land 2010年第4期2卷 257-265页

作者： Li, CongJuan Li, Yan Ma, Jian fan, lianlian Wang, QinXue Chinese Acad Sci Xinjiang Inst Ecol & Geog Fukang Stn Desert Ecol Urumqi 830011 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China Natl Inst Environm Studies Tsukuba Ibaraki 3058506 Japan

Spatial heterogeneity is a ubiquitous feature in natural ecosystems, especially in arid regions. Different species and their discontinuous distribution, accompanied by varied topographic characteristics, result in soil resources distributed differently in different locations, and present significant spatial heterogeneity in desert ecosystems. In this study, conventional and geostatistical methods were used to identify the heterogeneity of soil chemical properties in two desert populations, Haloxylon persicum Bunge ex Boss., which dominates on the slopes and tops of sand dunes and Haloxylon ammodendron (C. A. Mey.) Bunge, which inhabits interdunes in the Gurbantunggut Desert of Xinjiang, China. The results showed that soil pH, electrical conductivity (EC), soil organic carbon (SOC), available nitrogen (AN) and available phosphorus (AP) were significantly higher in H. ammodendron populations than that in H. persicum. The coefficient of variation (CV) indicated that (1) most parameters presented a moderate degree of variability (10% < CV < 100%) except pH in both plots, (2) the variability of soil pH, EC and AP in H. ammodendron populations was higher than that in H. persicum populations, and (3) SOC and AN in H. ammodendron populations were lower than that in H. persicum populations. Geostatistical analysis revealed a strong spatial dependence (C0/(C0+C) < 25%) within the distance of ranges for all tested parameters in both plots. The Kriging-interpolated figures showed that the soil spatial distribution was correlated with the vegetation distribution, individual size of plants, and the topographic features, especially with the plants nearest to sampling points and the topographic features. In each plot, soil EC, SOC, AN and AP presented similar distributions, and fertile islands and salt islands occurred in both plots but did not affect every individual plant, since the sampling distance was larger than the size of such fertile islands. The results of topogr

关键词： fertile island geostatistics plant population soil chemical properties spatial heterogeneity

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Elevated CO_(2) increases shoot growth but not root growth and C:N:P stoichiometry of Suaeda aralocaspica plants

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Journal of Arid Land 2021年第11期13卷 1155-1162页

作者： WANG Lei fan lianlian JIANG Li TIAN Changyan State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Research Center for Ecology and Environment of Central Asia Chinese Academy of SciencesUrumqi 830011China

The purpose of the current study was to investigate the eco-physiological responses,in terms of growth and C:N:P stoichiometry of plants cultured from dimorphic seeds of a single-cell C4 annual Suaeda aralocaspica(Bunge)Freitag and Schütze under elevated CO_(2).A climatic chamber experiment was conducted to examine the effects of ambient(720μg/L)and CO_(2)-enriched(1440μg/L)treatments on these responses in *** at vegetative and reproductive stages in *** showed that elevated CO_(2) significantly increased shoot dry weight,but decreased N:P ratio at both growth *** grown from dimorphic seeds did not exhibit significant differences in growth and C:N:P stoichiometric *** transition from vegetation to reproductive stage significantly increased shoot:root ratio,N and P contents,but decreased C:N,C:P and N:P ratios,and did not affect shoot dry ***,our results indicate that the changes in N:P and C:N ratios between ambient and elevated CO_(2) are mainly caused by the decrease of N content under elevated CO_(2).These results provide an insight into nutritional metabolism of single-cell C4 plants under climate change.

关键词： biomass CO_(2)elevation C:N:P stoichiometry seed heteromorphism Suaeda aralocaspica

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Transformation of vegetative cover on the Ustyurt Plateau of Central Asia as a consequence of the Aral Sea shrinkage

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Journal of Arid Land 2021年第1期13卷 71-87页

作者： Adilov BEKZOD Shomurodov HABIBULLO fan lianlian LI Kaihui MA Xuexi LI Yaoming Institute of Botany Academy of Sciences of UzbekistanTashkent 100125Uzbekistan CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

The gradual shrinkage of the Aral Sea has led to not only the degradation of the unique environments of the Aral Sea,but also numerous and fast developing succession processes in the neighborhood habitats surrounding the *** this study,we investigated the vegetative succession processes related to the Aral Sea shrinkage in the Eastern Cliff of the Ustyurt Plateau in Republic of Uzbekistan,Central *** compared the results of our current investigation(2010–2017)on vegetative communities with the geobotany data collected during the 1970s(1970–1980).The results showed great changes in the mesophytic plant communities and habitat aridization as a result of the drop in the underground water level,which decreased atmospheric humidity and increased the salt content of the soil caused by the shrinkage of the Aral *** the vegetative communities,we observed a decrease in the Margalef index(DMg),which had a positive correlation with the poly-dominance index(I-D).The main indications of the plant communities'transformation were the loss of the weak species,the appearance of new communities with low species diversity,the stabilization of the projective cover of former resistant communities,as well as the appearance of a new competitive species,which occupy new habitats.

关键词： plant cover mesophytic plant communities vegetative succession xerophytization biodiversity index climate change Aral Sea

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热岛效应对植物生长的影响以及叶片形态构成的适应性

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生态学报 2011年第20期31卷 5992-5998页

作者：王亚婷范连连中国科学院生态环境研究中心北京100085 中国科学院研究生院北京100049 中国科学院新疆生态与地理研究所乌鲁木齐830011

热岛效应是一种由于地表覆盖改变及人类活动导致的热量在城区空间范围内聚集的现象,是城市气候最明显的特征之一,随着越来越多的人口涌入城市以及伴随而生的超大城市的出现,城市热岛效应将更加凸显,这种环境温度的升高必将影响到各种景... 详细信息

热岛效应是一种由于地表覆盖改变及人类活动导致的热量在城区空间范围内聚集的现象,是城市气候最明显的特征之一,随着越来越多的人口涌入城市以及伴随而生的超大城市的出现,城市热岛效应将更加凸显,这种环境温度的升高必将影响到各种景观园林植物的生理状态乃至形态结构。选取以生长在热岛点和有大量绿植覆盖的低温点的两种典型园林植物大叶黄杨和丁香作为实验材料,研究了这两种植物叶在城市热岛效应影响下,在热岛点和低温点中的形态特征。结果表明,在热岛点环境温度和二氧化碳浓度显著高于低温点,但其他环境要素差异并不显著。热岛点的大叶黄杨和丁香叶生物量分别是低温点的1.6倍和1.4倍。进一步研究表明,相较于低温点,在热岛点生长的植物叶表现出较低的比叶面积、单位重量和单位面积叶氮含量。生物量在向各部分组织分配时,热岛点的植物叶倾向于将更多的生物量分配给叶肉部分,而减少了对叶柄的生物量投入。

关键词：热岛城市植物生物量

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低压低产气井排水采气工艺技术

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天然气工业 2005年第4期25卷 106-109页

作者：张书平白晓弘樊莲莲桂捷中国石油长庆油田分公司油气工艺技术研究院

针对长庆气田产水状况,文章总结了近几年来长庆气田排水采气工艺技术研究所所取得的成果,介绍了优选管柱排水采气、泡沫排水采气、柱塞气举排水采气等三种技术的工艺原理、工艺要求及各项工艺在长庆气田的试验效果,归纳了目前长庆气田... 详细信息

针对长庆气田产水状况,文章总结了近几年来长庆气田排水采气工艺技术研究所所取得的成果,介绍了优选管柱排水采气、泡沫排水采气、柱塞气举排水采气等三种技术的工艺原理、工艺要求及各项工艺在长庆气田的试验效果,归纳了目前长庆气田采用的三种行之有效的复产工艺措施,形成了长庆气田低压低产气井排水采气工艺技术体系,这对提高低压低产气井的采收率及高效开发具有指导意义。

关键词：气井排水采气工艺采收率地层临界携液流量加注工艺起泡剂消泡剂

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FCC汽油选择性加氢脱硫过程中烃类组成与辛烷值损失的关系

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石油炼制与化工 2010年第9期41卷 70-73页

作者：樊莲莲高晓冬习远兵石油化工科学研究院北京100083

以典型的FCC汽油重馏分为原料,在Co-Mo/Al_2O_3催化剂上进行选择性加氢脱硫试验。结果表明,烯烃加氢饱和是导致汽油加氢后辛烷值下降的主要原因。按照烯烃加氢后辛烷值损失的大小,将其分成五类。五类烯烃加氢饱和后辛烷值损失由大到小... 详细信息

以典型的FCC汽油重馏分为原料,在Co-Mo/Al_2O_3催化剂上进行选择性加氢脱硫试验。结果表明,烯烃加氢饱和是导致汽油加氢后辛烷值下降的主要原因。按照烯烃加氢后辛烷值损失的大小,将其分成五类。五类烯烃加氢饱和后辛烷值损失由大到小的顺序是:直链内烯烃〉直链端烯烃〉C_(7+)单支链烯烃〉环烯烃〉多支链和C_5、C_6支链烯烃。建立了烯烃变化量与辛烷值损失量的关联式,可以预测加氢汽油辛烷值的损失。

关键词：选择性加氢脱硫烯烃辛烷值

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榆林南地下储气库注采井完井管柱的优化设计

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天然气工业 2014年第1期34卷 92-96页

作者：汪雄雄樊莲莲刘双全韩强辉中国石油长庆油田公司油气工艺研究院 "低渗透油气田勘探开发"国家工程实验室

地下储气库注采井与常规气田开发井运行工况存在着很大差异，要求具有采气和注气双重功能，能够实时监测井下动态，在长期（30～50a）频繁剧烈的注采气和压差变化下能够确保井筒的密封性和安全性。为此，针对鄂尔多斯盆地榆林南地下储... 详细信息

地下储气库注采井与常规气田开发井运行工况存在着很大差异，要求具有采气和注气双重功能，能够实时监测井下动态，在长期（30～50a）频繁剧烈的注采气和压差变化下能够确保井筒的密封性和安全性。为此，针对鄂尔多斯盆地榆林南地下储气库注采井气量大、周期性强注强采的特点以及高安全性能、长使用寿命等的特殊要求，应用节点分析方法对天然气的流入、流出注采过程、不同尺寸油管注呆能力等进行了分析，并结合冲蚀流量和临界携液流量等的计算结果，最终确定了I类注采井（小于等于200×10^4m^3/d）采用p139．7mm油管，Ⅱ类注采井（小于等于80×10^4m^3／d）采用乃114．3mm油管。通过管柱结构优化设计，注采井采用井下悬挂压力计测压完井管柱，从上至下完井工具包括“上流动短节＋井下液控安全阀＋下流动短节＋循环滑套＋永久式封隔器＋磨铣延伸筒＋堵塞坐落短节＋带孔管＋悬挂坐落短节”等。现场2个注采周期运行试验结果表明，完井管柱能够满足地下储气库生产运行要求，其设计方法可供同类储气库注采井完井设计时参考。

关键词：鄂尔多斯盆地榆林南地下储气库完井管柱节点分析敏感性冲蚀流量完井工具井下安全阀强注强采

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靖边气田喷射器和压缩机组合增压新工艺

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天然气工业 2013年第5期33卷 96-99页

作者：刘双全汪雄雄樊莲莲韩强辉叶亮中国石油长庆油田公司油气工艺研究院 "低渗透油气田勘探开发"国家工程实验室

中国石油长庆油田公司靖边气田目前采用的压缩机增压工艺存在着高压气井能量利用率低、压缩机长期处于低载荷运行等突出问题。为此,在对靖边气田现有压缩机站运行现状及喷射器应用实践进行分析的基础上,提出了利用喷射器和压缩机进行组... 详细信息

中国石油长庆油田公司靖边气田目前采用的压缩机增压工艺存在着高压气井能量利用率低、压缩机长期处于低载荷运行等突出问题。为此,在对靖边气田现有压缩机站运行现状及喷射器应用实践进行分析的基础上,提出了利用喷射器和压缩机进行组合来增压的新模式。喷射增压可以充分利用高压气源的能量,实现低压气井增压,再与压缩机组合应用,可以明显提高增压站的能量利用效率。采用数值仿真技术对喷射器和压缩机组合应用模式进行了模拟计算,结果表明,该组合应用模式可以实现3个方面的应用效果:①对高压气井节流浪费的部分能量进行利用,可提升能量利用效率;②进一步降低被引射的低压井井口压力,可提高低压气井的最终采收率;③可减少压缩机低载荷运行时间,延长压缩机使用寿命,降低压缩机维护成本。结论认为,该工艺在气田增压稳产的中后期具有良好的经济效益和广阔应用前景。

关键词：靖边气田增压工艺喷射增压二级增压稳产压缩机节能增压喷射器

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