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滩涂围垦后土壤化学性质发生快速的变化,揭示其演变规律可以为土壤资源的可持续利用提供科学依据。以浙江省慈溪市东部滩涂围垦区为研究对象,用网格法采集滩涂沉积物和围垦区土壤样品,研究不同围垦年限和不同土地利用方式下土壤主要化学性质的变化特征。结果表明,围垦后土壤盐分含量经过急剧和缓慢降低两个阶段后,40年后趋于稳定。土壤p H在不断降低之后,和盐分含量水平一样,已适合多数作物的种植。有机质、全氮和全磷等养分相关指标在围垦后保持上升趋势。有机质含量在围垦30年后增速趋缓,目前仍处于较缺乏水平。土壤全氮保持持续增加趋势,但仍处于氮素缺乏状态,需要适当加大投入。土壤磷素供应能力已基本满足作物生长需求,未来只需在作物生长季节少量施用磷肥,保持磷素的输入/输出平衡。围垦初期,土地利用方式对土壤质量指标的影响明显,水田的脱盐效果最好,旱地土壤的肥力最高。而围垦超过40年的垦区内,不同土地利用方式间的土壤质量指标差异较小,各种农业种植方式都有利于围垦土壤的熟化。
After the reclamation of the tidal flat, the chemical properties of the soil changed rapidly, and the evolution of the reclaimed tidal flat could provide a scientific basis for the sustainable utilization of soil resources. Taking the reclamation area of beach in the east of Cixi City, Zhejiang Province as the research object, the tidal flat sediment and reclamation area soil samples were collected by grid method to study the change characteristics of main chemical properties of soils under different reclamation years and different land use types. The results showed that after the reclamation, the soil salinity content tended to be stable after 40 years after two stages of rapid and slow decrease. As soil pH decreases, it is suitable for planting most crops, just as salt levels. Organic matter, total nitrogen and total phosphorus and other nutrient-related indicators in the reclamation to maintain an upward trend. After 30 years of reclamation, the organic matter content has slowed down and is still at a relatively low level. Soil total nitrogen remained a trend of increasing, but still in a state of nitrogen deficiency, need to increase investment. Soil phosphorus supply capacity has basically met the crop growth needs, the future only a small amount of fertilizer application of crop growth season, to maintain the input / output balance of phosphorus. In the initial period of reclamation, the land use pattern had obvious influence on the soil quality index, the paddy field had the best desalination effect, and the dry land soil had the highest fertility. In the reclamation area reclaimed for more than 40 years, the differences in soil quality indicators among different land use types are small, and all kinds of agricultural planting methods are conducive to the maturation of reclaimed soil.