【作者】 于兴洋；

【导师】 王文杰； 杨逢建；

【作者基本信息】 东北林业大学 ， 植物学， 2010， 硕士

【摘要】 松嫩平原西部是我国盐碱土集中分布的地区之一,已成为世界三大苏打盐碱地集中分布区之一,重度盐碱地的修复一直是盐碱地治理的一个难点。本文在对重度盐碱地实施生态治理后,产生的土壤特性,植物光合及生长,生态学效应和“水-碳-盐”机理等研究后得到如下结论：1.重度盐碱地生态治理对对土壤特性影响：土壤总孔隙度较对照盐碱裸地(55.08%)提高了5%-20%,其中深槽改良土壤总孔隙度最高为75.35%。对照区盐碱裸地的土壤容重高达1.4g cm3。土壤电导率作为土壤盐分重要指标,四种不同改良措施都明显降低了土壤电导率,平均降低了1288 us cm-1,同时,土壤pH降低约1.5个单位。改良措施也提高了土壤养分,如碱解氮在深槽和浅槽改良分别较对照未处理提高了50%和100%。生态治理措施显著改善了土壤物理化学性质,有利于土壤进一步改良。2.重度盐碱地生态治理对对植物光合和生长的影响：改良后种植的植物光合能力方面也有不同提高,其中甘草、甜玉米和偃柏等经深槽处理后比对照提高2.5-12 gmol m2s-1。不同植物经过处理后在生物量方面明显提高,其中甜玉米、白菜、萝卜和偃柏等深槽处理大大高于其覆盖处理,说明这类植物对土壤有机质需求较高,而苜蓿、甘草、甜菜和假苍耳等在不同处理的生物量因适应性较强而导致差距并不明显。3.重度盐碱地为改良盐碱土,随着土壤剖面深度的提高,土壤水溶性钠离子、.交换性钠离子、ESP变化和pH值呈下降趋势,钠离子由表层0.2m(2.25 g kg-1)降低到4.4m(0.2688 g kg-1)。土壤交换性钠离子由0.8m(6.67 cmol kg-1)降低到4.4m(0.34 cmol kg-1)。土壤碱化度(ESP)由表层0.2m处(16.54%)降低到4.2m处(1.10%)。土壤水溶性钙、镁、钠、钾和钙离子呈现正相关,r>0.5,p<0.05。pH值由0.4m(9.84)降低到4.4m(9.07)。不同覆盖高度、不同土壤剖面深度和不同基质覆盖对土壤盐碱化程度和土壤肥力产生影响。其中覆盖厚度25cm,植被生物量最大,总和为加水1.1kg和不加水0.9kg。覆盖10cm,生物多样性指数Gleason指数和Margalef指数最大。碱解氮呈现下降趋势,其中覆盖处理中较高值分别为覆盖10cm(92.9 mg kg-1)和覆盖20cm(94.5 mg kg-1)；破坏处理与覆盖相似,其中最高值为破坏10cm(78.8 mg kg-1)。人工基质因有机质含量较高,故其碱解氮最大(106.9 mg kg-1)。pH值和电导率随覆盖厚度的提高而降低,降幅由0.11降到3.52,电导率也平均降低15μs cm-1到2500μs cm-1。不同覆盖材料pH值平均降低0.04-3.68,电导率平均降低24gs cm-1到2062μs cm-1之间,人工基质覆盖效果最为明显,pH值和电导率分别降低了3.61和2062μscm-1。更多还原

【Abstract】 Songnen Plain which western plains are concentrated saline-alkali soil in China is one of the regions. It has become the third of world’s Sodium regions. The severe alkali amelioration has been a difficult point. In this paper, through appling the the ecological amelioration of severe saline and alkali soil, we studied soil characteristics, photosynthesis, plant growth, ecological effects and mechanism of "water-carbon-salt". The conclusions are followed:1 The effect of saline and alkaline soil ecological amelioration on soil properties:soil total porosity increased by 5%-20% than the control (saline bare land 55.08%), with deep groove treatment the soil total porosity of up to 75.35%. Saline control area of bare land and soil bulk density as high as 1.4 g cm3. Soil electrical conductivity as an important indicator of soil salinity, four different measures have improved significantly reduced electrical conductivity of soil, the average reduced 1288 us cm-1, the same time, soil pH decreased about 1.5 units. Improvement measures to improve soil nutrients, such as the nitrogen tank in the deep grooves and shallow compared with the control untreated Improvement increased by 50% and 100%. Ecological control measures significantly improved the soil physical and chemical properties, the soil are conducive to further improvement.2. Ecological Governance severe alkali plant photosynthesis and growth:the improved cultivation of the plants have different photosynthetic capacity increase, which licorice, sweet corn and Yan Bo, etc. The deep groove treatment was increased 2.5-12 umol.m-2s-1. Processed in different plants obviously increased in biomass, including sweet corn, cabbage, radish, and Yan Bo, etc. groove processing is much higher than its coverage, it is proved the demand of these plants to high soil organic matter, and alfalfa, licorice, sugar beet and false cocklebur and other biomass in the different treatment because of the gap caused by strong adaptability is not obvious.3. For the improvement of severe saline soil, with the increase in soil depth, soil water-soluble sodium, exchangeable sodium, ESP changes and decreased pH value, sodium ions from the surface of 0.2m (2.25 g kg-1) down to 4.4m (0.2688 g kg-1). Soil exchangeable sodium was from the 0.8m (6.67 cmol kg-1) down to 4.4m (0.34 cmol kg-1). Soil alkalization degree (ESP) from the surface 0.2m layer (16.54%) decreased to 4.2m layer (1.10%). Soil water-soluble calcium, magnesium, sodium, potassium and calcium showed a positive correlation, r> 0.5, p <0.05. pH value from 0.4m (9.84) down to 4.4m (9.07). Different cover heights and different soil depths and different media coverage on the degree of soil salinization and soil fertility impact. Which cover thickness 25cm, maximum biomass, the sum of water and no water 1.1 kg 0.9 kg. Cover 10cm, biological diversity index and Margalef index of the largest Gleason. Downward trend in nitrogen, which covers treatment values were higher cover 10cm (92.9 mg kg-1) and cover 20cm (94.5 mg kg-1); damage to deal with similar coverage, with the highest value of damage 10cm (78.8 mg kg-1). Artificial substrate for the higher organic matter content, so the maximum nitrogen (106.9 mg kg-1). pH value and conductivity, the thickness of the increase and decrease coverage, down from 0.11 down to 3.52, the average conductivity is also lower 15μs cm-1 to 2500μs cm-1. The average pH value of different mulch materials reduce 0.04-3.68, the average conductivity decreased 24μs cm-1 to 2062μs cm-1, between the most obvious coverage of artificial substrate, pH, and conductivity decreased by 3.61 and 2062μs cm-1.更多还原