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Carbon storage in a wolfberry plantation chronosequence established on a secondary saline land in an arid irrigated area of Gansu Province,China

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Journal of Arid Land 2018年第2期10卷 202-216页

作者： ma quanlin WANG Yaolin LI Yinke SUN Tao Eleanor MILNE State Key Laboratory of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research InstituteLanzhou 730070China Natural Resource Ecology Laboratory Colorado State UniversityFort Collins CO 80523-1499USA

Carbon（C） storage has received significant attention for its relevance to agricultural security and climate change. Afforestation can increase C storage in terrestrial ecosystems, and has been recognized as an important measure to offset CO_2 emissions. In order to analyze the C benefits of planting wolfberry（Lycium barbarum L.） on the secondary saline lands in arid areas, we conducted a case study on the dynamics of biomass carbon（BC） storage and soil organic carbon（SOC） storage in different-aged wolfberry plantations（4-, 7-and 11-year-old） established on a secondary saline land as well as on the influence of wolfberry plantations on C storage in the plant-soil system in an arid irrigated area（Jingtai County） of Gansu Province, China. The C sequestration and its potential in the wolfberry plantations of Gansu Province were also evaluated. An intact secondary saline land was selected as control. Results show that wolfberry planting could decrease soil salinity, and increase BC, SOC and litter C storage of the secondary saline land significantly, especially in the first 4 years after planting. The aboveground and belowground BC storage values in the intact secondary saline land（control） accounted for only 1.0% and 1.2% of those in the wolfberry plantations, respectively. Compared to the intact secondary saline land, the SOC storage values in the 4-, 7-and 11-year-old wolfberry plantations increased by 36.4%, 37.3% and 43.3%, respectively, and the SOC storage in the wolfberry plantations occupied more than 92% of the ecosystem C storage. The average BC and SOC sequestration rates of the wolfberry plantations for the age group of 0–11 years were 0.73 and 3.30 Mg C/（hm^2·a）, respectively. There were no significant difference in BC and SOC storage between the 7-year-old and 11-year-old wolfberry plantations, which may be due in part to the large amounts of C offtakes in new branches and fruits. In Gansu Province, the C storage in the wolfberry plantations has reached up

关键词： Lycium barbaum biomass carbon soil organic carbon carbon sequestration potential secondary saline land wolfberry plantation carbon dynamics

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Spatial heterogeneity of soil water content in the reversion process of desertification in arid areas

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Journal of Arid Land 2011年第4期3卷 268-277页

作者： quanlin ma Fang CHENG YouJun LIU FangLin Wang DeKuai ZHANG HuJia JIN Gansu Key Laboratory of Desertification Combating ＆ Minqin National Studies Station for Desert Steppe Ecosystem Gansu Desert Control Research Institute Lanzhou 730070 China Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Sandy soils in arid,rain-fed environments have low and limited water content,which is a principal factor limiting vegetation development,and a key constraint controlling the structure and functions of the ecological systems in arid *** spatial heterogeneity of soil water content is a major soil property,and a focus of soil science and *** the southern edge of the Tengger Desert,sample plots were selected from mobile sand dunes in desertified lands that had been enclosed for 5,15 and 25 years,*** study explored the dynamic and spatial heterogeneity of soil water content in these different layers of soil that were also in the reversion process of *** results showed that the soil water content of the mobile sand dunes was highest when in the initial stages of the reversion process of desertification,while the soil water content in the 0-20 cm,20-40 cm and 40-60 cm layers of soil was 1.769%,3.011%,and 2.967% respectively,presenting a restoring tendency after 25 years of *** were significant differences,as a whole,in the soil water content among different restoration stages and different soil layers,*** in soil water content,in different soil layers,at different restoration stages,exhibited exponential or spherical *** spatial distribution of soil water content exhibited a mosaic patch pattern with obvious spatial *** ratio of the heterogeneity of spatial autocorrelation to gross spatial heterogeneity was greater than 50%.The gross spatial heterogeneity of the 0-20 cm layer of soil improved gradually,while those of the 20-40 cm and 40-60 cm layers improved initially,then weakened in the reversion process of *** study revealed that restoration with sand-binding vegetation reduced soil water content,and increased its spatial heterogeneity in arid ***,after 25 years of vegetation-soil system restoration,the soil water content started to increase and it

关键词： Tengger Desert reversion process of desertification soil water content sand-binding vegetation geostatistical analysis

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Utilizing sediment grain size characteristics to assess the effectiveness of clay–sand barriers in reducing aeolian erosion in Minqin desert area,China

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Journal of Arid Land 2024年第5期16卷 668-684页

作者： SONG Dacheng ZHAO Wenzhi LI Guangyu WEI Lemin WANG Lide YANG Jingyi WU Hao ma quanlin College of Forestry Gansu Agricultural UniversityLanzhou 730070China Gansu Hexi Corridor Forest Ecosystem National Research Station Gansu Desert Control Research InstituteLanzhou 730070China Linze Inland River Basin Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The clay–sand barriers in Minqin desert area,China,represent a pioneering windbreak and sand fixation project with a venerable history of 60 ***,studies on evaluating the long-term effectiveness of clay–sand barriers against aeolian erosion,particularly from the perspective of surface sediment grain size,are limited and thus insufficient to ascertain the protective impact of these barriers on regional aeolian *** study focused on the surface sediments(topsoil of 0–3 cm depth)of clay–sand barriers in Minqin desert area to explain their erosion resistance from the perspective of surface sediment grain *** march 2023,six clay–sand barrier sampling plots with clay–sand barriers of different deployment durations(1,5,10,20,40,and 60 a)were selected as experimental plots,and one control sampling plot was set in an adjacent mobile sandy area without sand *** sediment samples were collected from the topsoil of each sampling plot in the study area in April 2023 and sediment grain size characteristics were *** indicated a predominance of fine and medium sands in the surface sediments of the study *** deployment of clay–sand barriers cultivated a fine quality in grain size composition of the regional surface sediments,increasing the average contents of very fine sand,silt,and clay by 30.82%,417.38%,and 381.52%,*** trend became markedly pronounced a decade after the deployment of clay–sand *** effectiveness of clay–sand barriers in erosion resistance was manifested through reduced wind velocity,the interception of sand flow,and the promotion of fine surface sediment *** particles such as medium,coarse,and very coarse sands predominantly accumulated on the external side of the barriers,while finer particles such as fine and very fine sands concentrated in the upwind(northwest)region of the *** contrast,the contents of finest particles such as silt and clay were higher in the downwind

关键词： clay-sand barriers sediment grain size grain size distribution aeolian erosion windbreak and sand fixation Minqin desert area

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Effects of Caragana microphylla plantations on organic carbon sequestration in total and labile soil organic carbon fractions in the Horqin Sandy Land, northern China

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Journal of Arid Land 2017年第5期9卷 688-700页

作者： SHANG Wen LI Yuqiang ZHAO Xueyong ZHANG Tonghui ma quanlin TANG Jinnian FENG Jing SU Na State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research Institute Lanzhou 730070 China Naiman Desertification Research Station Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China

Afforestation is conducive to soil carbon（C） sequestration in semi-arid regions. However, little is known about the effects of afforestation on sequestrations of total and labile soil organic carbon（SOC） fractions in semi-arid sandy lands. In the present study, we examined the effects of Caragana microphylla Lam. plantations with different ages（12-and 25-year-old） on sequestrations of total SOC as well as labile SOC fractions such as light fraction organic carbon（LFOC） and microbial biomass carbon（MBC）. The analyzed samples were taken from soil depths of 0–5 and 5–15 cm under two shrub-related scenarios： under shrubs and between shrubs with moving sand dunes as control sites in the Horqin Sandy Land of northern China. The results showed that the concentrations and storages of total SOC at soil depths of 0–5 and 5–15 cm were higher in 12-and 25-year-old C. microphylla plantations than in moving sand dunes（i.e., control sites）, with the highest value observed under shrubs in 25-year-old C. microphylla plantations. Furthermore, the concentrations and storages of LFOC and MBC showed similar patterns with those of total SOC at the same soil depth. The 12-year-old C. microphylla plantations had higher percentages of LFOC concentration to SOC concentration and MBC concentration to SOC concentration than the 25-year-old C. microphylla plantations and moving sand dunes at both soil depths. A significant positive correlation existed among SOC, LFOC, and MBC, implying that restoring the total and labile SOC fractions is possible by afforestation with C. microphylla shrubs in the Horqin Sandy Land. At soil depth of 0–15 cm, the accumulation rate of total SOC under shrubs was higher in young C. microphylla plantations（18.53 g C/（m^2·a）; 0–12 years） than in old C. microphylla plantations（16.24 g C/（m^2·a）; 12–25 years）, and the accumulation rates of LFOC and MBC under shrubs and between shrubs were also higher in young C. microphylla plantations than in old C. microphylla plantat

关键词： Caragana microphylla plantation soil organic carbon light fraction organic carbon microbial biomass carbon carbon accumulation rate Horqin Sandy Land

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运用QC管理方法解决缸盖大面针孔难题

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特种铸造及有色合金 2008年第8期28卷 613-614页

作者：马泉林周麟升重庆红旗缸盖制造有限公司

针对铝合金汽车缸盖大面针孔(二级以上)导致废品率高达30%的问题,成立了QC小组,经过3次PDCA循环,从"人、机、料、法、环"等方面找原因,第一次找到的原因一是精炼不足,二是浇注温度偏高,第二次找到的原因是模具温度偏高,第三次找到的原... 详细信息

针对铝合金汽车缸盖大面针孔(二级以上)导致废品率高达30%的问题,成立了QC小组,经过3次PDCA循环,从"人、机、料、法、环"等方面找原因,第一次找到的原因一是精炼不足,二是浇注温度偏高,第二次找到的原因是模具温度偏高,第三次找到的原因是模具本身有问题。解决方案是将燃烧室大面进水工艺改为框面进水工艺,即改造模具,将原浇口芯模报废,增加一副浇口芯模,结果针孔问题基本解决,废品率降至1.36%。

关键词： QC管理铝合金汽车缸盖针孔废品率

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3D Velocity Structure and Its Tectonic Implications in the East China Sea and Yellow Sea

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Acta Geologica Sinica(English Edition) 1993年第3期67卷 273-296页

作者： Feng Rui, Zhou Hainan, Institute of Geophysics, State Seismological Bureau, Beijing Yao Zhengsheng, Seismological Institute of Lanzhou, Lanzhou ma Guiming and Li quanlin Institute of Geophysics, State Seismological Bureau Beijing Fei Zhenbi

3D structure of the crust and upper mantle in the studied area has been analyzed from surface wave tomography. The velocity distribution in the uppermost crust is symmetrical on two sides of the central line of the sea, and coincides with the structure of crystalline basement. The essential difference in tectonics between the East China Sea and the Yellow Sea mainly lies in that the velocity structures of their lower crust and upper mantle are identical to those of South China and North China respectively. In the upper mantle there exists a high-velocity zone with a nearly EW strike from the Hangzhou Bay, China, to the Tokara Channel, Japan, along about the latitude of 30°N. It is found that between the East China Sea and the Yellow Sea there are systematical differences in geomorphology, geology, seismicity, heat flow, quality factor and gravity and aeromagnetic anomalies, which is related to both left-lateral shear dislocation and right-lateral tear of the Benioff zone from the Hangzhou Bay to the Tokara Channel.It is inferred that the East China Sea was formed by Cenozoic back-arc extension. The boundary between the North China and South China crustal blocks stretches along the southern piedmont of Mts. Daba-Dabie-Hangzhou Bay-Tokara Channel, and the subduction zone at the Okinawa trench is the eastern boundary of the South China crustal block. The movements of the Pacific plate, Indian plate and upper mantle rather than the Philippine plate subduction have played a dominant role for the modern tectonic movements in East Asia.

关键词： East China Sea and Yellow Sea 3D velocity structure surface wave tomography the Hang zhou Bay-Tokara Channel transform fault North China crustal block South China crustal block

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干旱荒漠白刺灌丛植被演替过程土壤种子库变化特征

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生态学报 2015年第7期35卷 2285-2294页

作者：马全林卢琦魏林源靳虎甲中国林业科学研究院荒漠化研究所北京100091 甘肃省治沙研究所荒漠化与风沙灾害防治国家重点实验室培育基地兰州730070

土壤种子库是反映气候与土地利用变化的指示器,也是荒漠植被更新与恢复的基础。典型荒漠白刺灌丛植被广泛分布于我国西北绿洲边缘地带,对保护绿洲免受风沙危害发挥着重要作用。但是,对干旱荒漠白刺灌丛植被土壤种子库仍未见研究报道。... 详细信息

土壤种子库是反映气候与土地利用变化的指示器,也是荒漠植被更新与恢复的基础。典型荒漠白刺灌丛植被广泛分布于我国西北绿洲边缘地带,对保护绿洲免受风沙危害发挥着重要作用。但是,对干旱荒漠白刺灌丛植被土壤种子库仍未见研究报道。应用空间代替时间的方法,选择石羊河下游白刺灌丛植被演替的初始阶段、稳定阶段、衰退阶段与严重衰退阶段样地,研究了白刺灌丛植被演替过程的土壤种子库物种组成、时空分布和数量变化特征。结果表明:石羊河下游白刺灌丛植被演替过程中,土壤种子库共出现9科18种植物,其中草本植物占到55%—80%,是白刺灌丛植被土壤种子库的主体。不同演替阶段土壤种子库密度以稳定阶段最高,达到660.7粒/m2,是初始阶段、衰退阶段和严重衰退阶段的5.6、14.5倍和6.2倍。不同沙堆部位,土壤种子库密度以迎风坡中部与背风坡中部最高,分别达到329粒/m2和309粒/m2;沙堆土壤种子库密度是堆间地的1.9倍,土壤种子库主要分布于灌丛沙堆上。不同演替阶段土壤种子库间的相似性系数均在0.6以下,除稳定阶段外,其他阶段间均属于中等相似水平;土壤种子库与地上植被的相似性系数均在0.5以上,达到中等相似或极相似水平。该研究进一步证明了灌丛沙堆和土壤种子库在白刺灌丛植被中的重要性,也说明人为干扰损害了白刺灌丛地下潜在植被及其恢复潜力。因此,需要开展人工种子库或人工植被建设以控制干旱荒漠白刺灌丛沙堆活化,并实现退化白刺灌丛植被恢复。

关键词：石羊河下游白刺灌丛植被灌丛沙堆土壤种子库相似性

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甘肃马鬃山地区种子植物多样性研究

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干旱区资源与环境 2009年第7期23卷 188-190页

作者：汪之波孙继周马全林天水师范学院生命科学和化学学院天水741000 兰州大学生命科学学院兰州730000 甘肃省荒漠化防治重点实验室武威733000

对甘肃肃北马鬃山地区的种子植物多样性进行了调查,结果表明:马鬃山地区的种子植物有25科65属112种。其中裸子植物1科1属3种,被子植物24科65属112种;马鬃山地区的植被类型大致分为5个植被型组;马鬃山地区分布着国内罕见、甘肃省面积最... 详细信息

对甘肃肃北马鬃山地区的种子植物多样性进行了调查,结果表明:马鬃山地区的种子植物有25科65属112种。其中裸子植物1科1属3种,被子植物24科65属112种;马鬃山地区的植被类型大致分为5个植被型组;马鬃山地区分布着国内罕见、甘肃省面积最大而且保存最完整的天然梭梭林;最后论述了马鬃山地区天然梭梭林的保护价值并且提出了保护建议。

关键词：马鬃山种子植物多样性梭梭

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