Luo Jin-Ming, Wang Yong-Jie, Deng Wei, Ye Ya-Jie, Zhang Xiao-Ping
Department of Physical and Geography, Qiqihar University, Qiqiha, Heilongliang, China.
Ying Yong Sheng Tai Xue Bao. 2009 Aug;20(8):1912-7.
The study by the methods of in situ observation and laboratory analysis showed that the micro-relief in salinization area of Songnen Plain area was composed of flat land, micro-slope land, depression margin, and depression. Isohumusols distributed in depression, while alkalic halosols distributed in depression margin, micro-slope land, and flat land. The exchangeable sodium percent (ESP) in alkalized layer (15-30 cm) of alkaline soil in flat land was 60%, and the maximal ESP in surface soil layer in micro-slope land could reach to 75%. The alkalized soil layer in depression margin was mainly at the depth of 10-30 cm, where the maximal ESP could reach to 30% -40%. Nearly no alkalized layer was found in the soil profile in depression. The soils developed on the four micro-relief units had obvious differences in their water retention curves. The maximal saturation moisture content in the soils of micro-slope land was only 25%, while that of 0-10 cm soil layer in depression reached to 45%. The freezing-thawing process in different micro-relief units differed markedly, with the maximal frozen depth in micro-slope land and depression being 157 and 136 cm, respectively. The surface soil moisture content in depression increased from 20% before freezing to 50% during freezing period. Among the four micro-relief units, micro-slope land had the most obvious variation of surface soil salt content during freezing-thawing, with the increment after thawing being as high as 80%.
通过原位观测和实验室分析方法的研究表明，松嫩平原盐碱化区域的微地貌由平地、微坡地、洼地边缘和洼地组成。腐殖质土分布在洼地，而碱性盐土分布在洼地边缘、微坡地和平地。平地碱性土壤碱化层（15 - 30厘米）的交换性钠百分比（ESP）为60%，微坡地表层土壤层的最大ESP可达75%。洼地边缘的碱化土层主要在10 - 30厘米深度，最大ESP可达30% - 40%。洼地土壤剖面中几乎未发现碱化层。在这四个微地貌单元上发育的土壤在持水曲线上有明显差异。微坡地土壤的最大饱和含水量仅为25%，而洼地0 - 10厘米土层的最大饱和含水量达到45%。不同微地貌单元的冻融过程差异显著，微坡地和洼地的最大冻深分别为157厘米和136厘米。洼地表层土壤含水量从冻结前的20%增加到冻结期的50%。在这四个微地貌单元中，微坡地在冻融过程中表层土壤盐分含量变化最为明显，解冻后的增量高达80%。
