腾格里沙漠草方格固沙林土壤颗粒组成、分形维数及其对土壤性质的影响
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摘要
为了明确草方格人工固沙造林植被恢复过程中土壤颗粒组成、分形维数及对土壤理化性质的影响,以腾格里沙漠东南缘2016年(1 a)、2013年(4 a)和1987年(30 a)草方格固沙林为研究样地,以周围流动沙地为对照(CK),研究了草方格固沙造林后植被恢复过程中土壤颗粒组成、分形维数及与土壤理化性质的作用关系.结果表明:100～250、250～500μm土壤颗粒含量较高,分别为42.5%～80.1%、12.5%～42.2%; 50～100μm土壤颗粒含量居中,为0.2%～20.8%;<2和2～50μm的土壤颗粒含量次之,分别在0～1. 3%和0～22. 7%;而500～1000μm的土壤颗粒含量较低,在0.3%以下.<2和2～50μm土壤颗粒仅在30 a固沙林有分布; 50～100μm土壤颗粒分布为30 a最高,4 a和1 a居中,而CK最低; 100～250μm土壤颗粒分布依次为4 a>1 a>CK>30 a; 250～500μm土壤颗粒分布为CK>1 a>4 a>30 a;但500～1000μm土壤颗粒在各样地分布均较少,且不同样地之间无显著差异.研究区土壤颗粒分形维数为0.54～2.59,并且不同样地间存在显著差异,表现为30 a最高,4 a与1 a居中,而CK最低.土壤颗粒分形维数与土壤黏粒、粉粒、极细砂粒含量呈极显著正相关,而与土壤中砂粒呈极显著负相关.土壤颗粒分形维数与土壤电导率、有机碳、全氮和碳氮比均呈极显著正相关,而与土壤p H和含水量无相关性.土壤中<2、2～50、50～100μm颗粒与土壤电导率、有机碳、全氮和碳氮比均呈极显著正相关,而250～500μm土壤颗粒与上述4个土壤指标和土壤含水量呈显著负相关.500～1000μm土壤颗粒与土壤含水量亦呈极显著负相关.在腾格里沙漠东南缘地区利用草方格进行人工固沙植被建设,可有效促进土壤颗粒细粒化,长期演变导致土壤黏粒和粉粒及土壤分形维数显著增加,促使土壤有机碳和全氮含量提高,有利于土壤理化性质改善和促进沙漠化治理.
This study aims to elucidate the effects of soil particle composition and fractal dimension on soil physical and chemical properties following sand-binding revegetation within straw checkerboard in south-eastern Tengger Desert. Three afforested plantations in the year of 2016( i. e.,1year),2013( i.e.,4 years) and 1987( i.e.,30 years) were selected as study sites,with the adjacent mobile sand land as control( CK). We measured soil particle composition,soil fractal dimension,and the changes of soil physical and chemical properties. The relationship between soil particle composition,soil fractal dimension,and soil properties was analyzed. The results showed that contents of soil particle with the size of both 100-250 μm and 250-500 μm were greater than that of 50-100 μm,ranging from 42.5% to 80.1% and from 12.5% to 42.2% relative to that ranging from 0.2% to 20.8%. Contents of soil particle with the size of <2 μm and 2-50 μm were remarkably lower than that of 100-250 μm,250-500 μm and 50-100 μm,ranging from 0 to 1.3% and from 0 to 22.7%,respectively. However,contents of soil particle at the size of 500-1000 μm was the lowest occupying <0.3% of soil particle composition. Soil particle with the size of < 2 μm and2-50 μm were found in the 30-year sites only. Soil particle distribution at the size of 50-100 μm,100-250 μm,and 250-500 μm followed the order of 30 a>1 a>4 a>CK,4 a>1 a>CK>30 a,and CK>1 a>4 a> 30 a,respectively. Soil particle with the size of 500-1000 μm occupied little of soil particle composition,with no significant difference between each site. The fractal dimension of soil particles ranged from 0.54 to 2.59. There was significantly greater soil fractal dimension in 30 a in comparison to 4 a,1 a and CK,with the intermediate values in 4 a and 1 a,and the lowest values in CK. There was a significantly positive correlation of fractal dimension of soil particles with soil particle content of clay,silt,very fine sand,and a significantly negative correlation of fractal dimension of soil particles with soil particle content of medium sand. Fractal dimension of soil particles was positively correlated with soil electrical conductivity,organic carbon,total nitrogen,and carbon-nitrogen ratio,but with no correlation with soil p H and soil water content. Soil particle content at the size of <2 μm,2-50 μm,and 50-100 μm had a significant positive correlation with soil electrical conductivity,organic carbon,total nitrogen,and carbon-nitrogen ratio,whereas soil particle content at the size of 250-500 μm had a negative correlation with the former four soil indices and soil water content. In addition,there was a significant negative correlation of soil particle content at the size of 500-1000 μm with soil water content. It was concluded that the sand-binding revegetation within straw checkerboard in Tengger Desert could facilitate the fine soil particles by ameliorating stressful soil conditions. Long-term succession of revegetation on mobile sand land could enhance soil clay and silt content as well as soil fractal dimension,thus be beneficial for the improvement of soil physical and chemical properties and desertification control.
This study aims to elucidate the effects of soil particle composition and fractal dimension on soil physical and chemical properties following sand-binding revegetation within straw checkerboard in south-eastern Tengger Desert. Three afforested plantations in the year of 2016( i. e.,1year),2013( i.e.,4 years) and 1987( i.e.,30 years) were selected as study sites,with the adjacent mobile sand land as control( CK). We measured soil particle composition,soil fractal dimension,and the changes of soil physical and chemical properties. The relationship between soil particle composition,soil fractal dimension,and soil properties was analyzed. The results showed that contents of soil particle with the size of both 100-250 μm and 250-500 μm were greater than that of 50-100 μm,ranging from 42.5% to 80.1% and from 12.5% to 42.2% relative to that ranging from 0.2% to 20.8%. Contents of soil particle with the size of <2 μm and 2-50 μm were remarkably lower than that of 100-250 μm,250-500 μm and 50-100 μm,ranging from 0 to 1.3% and from 0 to 22.7%,respectively. However,contents of soil particle at the size of 500-1000 μm was the lowest occupying <0.3% of soil particle composition. Soil particle with the size of < 2 μm and2-50 μm were found in the 30-year sites only. Soil particle distribution at the size of 50-100 μm,100-250 μm,and 250-500 μm followed the order of 30 a>1 a>4 a>CK,4 a>1 a>CK>30 a,and CK>1 a>4 a> 30 a,respectively. Soil particle with the size of 500-1000 μm occupied little of soil particle composition,with no significant difference between each site. The fractal dimension of soil particles ranged from 0.54 to 2.59. There was significantly greater soil fractal dimension in 30 a in comparison to 4 a,1 a and CK,with the intermediate values in 4 a and 1 a,and the lowest values in CK. There was a significantly positive correlation of fractal dimension of soil particles with soil particle content of clay,silt,very fine sand,and a significantly negative correlation of fractal dimension of soil particles with soil particle content of medium sand. Fractal dimension of soil particles was positively correlated with soil electrical conductivity,organic carbon,total nitrogen,and carbon-nitrogen ratio,but with no correlation with soil p H and soil water content. Soil particle content at the size of <2 μm,2-50 μm,and 50-100 μm had a significant positive correlation with soil electrical conductivity,organic carbon,total nitrogen,and carbon-nitrogen ratio,whereas soil particle content at the size of 250-500 μm had a negative correlation with the former four soil indices and soil water content. In addition,there was a significant negative correlation of soil particle content at the size of 500-1000 μm with soil water content. It was concluded that the sand-binding revegetation within straw checkerboard in Tengger Desert could facilitate the fine soil particles by ameliorating stressful soil conditions. Long-term succession of revegetation on mobile sand land could enhance soil clay and silt content as well as soil fractal dimension,thus be beneficial for the improvement of soil physical and chemical properties and desertification control.
引文
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[2] Wang R-H(王让会). Eco-effect Research of Ecological Engineering. Beijing:Science Press,2016(in Chinese)
[3] Le Houerou HN. Restoration and rehabilitation of arid and semiarid Mediterranean ecosystems in North Africa and West Asia:A review. Arid Soil Research and Rehabilitation,2000,14:3-14
[4] Deng L,Shangguan ZP,Sweeney S,et al. Changes in soil carbon and nitrogen following land abandonment of farmland on the Loess Plateau, China. PLo S One,2013,8(8):e71923
[5] Song X,Peng C,Zhou G,et al. Chinese grain for green program led to highly increased soil organic carbon levels:A meta-analysis. Scientific Reports,2014,4:4460
[6] Dai Q-H(戴全厚),Xue S(薛萐). The synergistic effect between vegetation recovery and soil quality on abandoned arable land in eroded hilly Loess Plateau.Scientia Agricultura Sinica(中国农业科学),2008,41(5):1390-1399(in Chinese)
[7] Luo F-M(罗凤敏),Gao J-L(高君亮),Hao Y-G(郝玉光),et al. Soil grain size characteristics of five land use types in the northeastern margin of Ulan Buh Desert. Research of Soil and Water Conservation(水土保持研究),2017,24(5):172-177(in Chinese)
[8] Li X-B(李学斌),Zhang Y-F(张义凡),Chen L(陈林),et al. Relationship between soil particle size distribution and soil nutrient distribution characteristics in typical communities of desert grassland. Acta Botanica Boreali-Occidentalia Sinica(西北植物学报),2017,37(8):1635-1644(in Chinese)
[9] Jia W-F(贾文峰). The Research on Quality Evolution of the Artificial Oasis Soil on the Eastern Edge of Ulan Buh Desert. PhD Thesis. Huhhot:Inner Mongolia Agricultural University,2009(in Chinese)
[10] Li XR,Xiao HL,He MZ,et al. Sand barriers of straw checkerboards for habitat restoration in extremely arid desert regions. Ecological Engineering,2006,28:149-157
[11] Fearnehough W,Fullen MA,Mitchell DJ,et al. Aeolian deposition and its effect on soil and vegetation changes on stabilized desert dunes in northern China. Geomorphology,1998,23:171-182
[12] Li X-R(李新荣),Zhou H-Y(周海燕),Wang X-P(王新平),et al. Ecological restoration and recovery in arid desert regions of China:A review for 60-year research progresses of Shapotou Desert research and experiment station, Chinese Academy of Sciences.Journal of Desert Research(中国沙漠),2016,36(2):247-264(in Chinese)
[13] Zhao L(赵来),Lyu C-W(吕成文). Study on relation between fractal features and fertility of soil take paddy soil in southern area of Anhui Province for example.Soil and Fertilizer Sciences in China(中国土壤与肥料),2005(6):7-11(in Chinese)
[14] Zou C(邹诚),Xu F-L(徐福利),Yan Y-D(闫亚丹). The analysis of soil mechanical composition and available nutrient under different land uses patterns in the Loess Hilly Gully Region. Chinese Agricultural Science Bulletin(中国农学通报),2008,24(12):424-427(in Chinese)
[15] Yao J-Z(姚姣转),Liu T-X(刘廷玺),Tong X(童新),et al. Soil particle fractal dimension in the dunemeadow ecotone of the Horqin Sandy Land. Journal of Desert Research(中国沙漠),2016,36(2):433-440(in Chinese)
[16] Jia X-H(贾晓红),Li X-R(李新荣),Zhang J-G(张景光),et al. Spatial heterogeneity analysis of fractal dimension of soil particle for Ammopiptanhus mongolicus shrub. Acta Ecologica Sinica(生态学报),2006,26(9):2827-2833(in Chinese)
[17] Cleveland CC,Liptzin D. C:N:P stoichiometry in soil:Is there a “Redfield ratio”for the microbial biomass?Biogeochemistry,2007,85:235-252
[18] Li X-R(李新荣),Zhang Z-S(张志山),Tan H-J(谭会娟),et al. Ecological restoration and recovery in the wind-blown sand hazard areas of northern China:Relationship between soil water and carrying capacity for vegetation in the Tengger Desert. Scientia Sinica Vitae(中国科学:生命科学),2014,44(3):257-266(in Chinese)
[19] Qin Y-D(秦耀东). Soil Physics. Beijing:Higher Education Press,2003(in Chinese)
[20] Tyler SW,Wheatcraft SW. Fractal scaling of soil particle size distributions:Analysis and limitations. Soil Science Society of America Journal,1992,56:362-369
[21] Huang C-Y(黄昌勇). Soil Science. Beijing:China Agriculture Press,2010(in Chinese)
[22] Li C(李超),Dong Z-B(董治宝),Cui X-J(崔徐甲). Grain-size characteristics of transverse dune during different developmental stages in the southeastern edge of the Tengger Desert. Journal of Desert Research(中国沙漠),2015,35(1):129-135(in Chinese)
[23] Shi M(施明),Wang R(王锐),Sun Q(孙权),et al. Vegetation restoration and soil nutrient changes in edge of Tengger Desert. Bulletin of Soil and Water Conservation(水土保持通报),2013,33(6):107-111(in Chinese)
[24] Zhang Y-F(张义凡),Chen L(陈林),Li X-B(李学斌),et al. Relationship between soil particle size distribution and microbial biomass carbon and nitrogen in 3typical communities of desert grassland. Acta Botanica Boreali-Occidentalia Sinica(西北植物学报),2016,36(12):2513-2523(in Chinese)
[25] Yang W-B(杨文斌). Desertification Control with Low Coverage Vegetation. Beijing:Science Press,2016(in Chinese)
[26] Wang G-M(王艮梅),Ma A-J(马爱军),Xia Y(夏钰). Distribution of soil active organic carbon under different management patterns of poplar plantation. Ecology and Environment(生态环境学报),2015,24(11):1771-1776(in Chinese)
[27] Xu T-T(许婷婷),Dong Z(董智),Li H-L(李红丽),et al. Distribution of soil particle size and soil organic carbon in dunes of checkerboard barriers with different setting years. Research of Environmental Sciences(环境科学研究),2014,27(6):628-634(in Chinese)
[28] Cang M-L(仓木拉),Mu L(木兰),Wang X-D(王晓栋),et al. Spatial distribution of soil particle size and its correlation with soil moisture in Cragana Tibetica community. Journal of Domestic Animal Ecology(家畜生态学报),2014,35(9):23-27(in Chinese)
[29] Li XR,Wang XP,Li T,et al. Microbiotic crust and its effect on vegetation and habitat on artificially stabilized desert dunes in Tengger Desert,northern China. Biology and Fertility of Soils,2002,35:147-154
[30] Li X,Xiao X,Liu L,et al. Long-term effects of sandbinding vegetation on the restoration of biodiversity in Shapotou region of Tengger Desert, northern China.Journal of Desert Research,2004,25:173-181
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