宁夏设施与露地土壤理化性状对比

根据宁夏灌区温室的分布状况，采集设施栽培与露地栽培表层(0~20 cm)土壤，对同地域设施土壤与露地土壤进行对比分析。结果表明，宁夏设施土壤，在物理性状上与露地土壤相比水稳性团聚体显著增加，而土壤体积质量显著降低，通气孔隙度、田间持水量和自然水质量含量增加较小，未达到显著差异；在化学性状上，设施土壤有机质、全盐以及碱解氮、速效P、K质量分数均显著提高，而pH显著降低，微量元素质量分数除有效Fe显著提高外，有效B、有效Zn、有效Mn、有效Cu均升高不明显，但是土壤有效Zn和有效Cu质量分数与其背景值相比均在高指标范围内，因Zn和Cu都属于重金属元素，因此，在确定施肥量及农事操作时应重点予以考虑。

Comparison of Physical and Chemical Properties between Soils of Protected and Open Cultivation in Ningxia Province

Based on distribution of greenhouse in irrigation regions of Ningxia, the soil samples of top soil (0-20 cm) were collected by means of random sampling for both the facility cultivation soil and open cultivation soil. Chemical and physical properties were compared between the soils of protected and open cultivation. The results showed that the water stable aggregate in the protected field were significantly increased compare to the open field, but soil capillary porosities and field water capacities and soil water contents were a few increased, however, the soil bulk densities were significantly reduced. For the chemical properties of the soils, the soil organic matter, salt contents, alkali-hydro. N contents and available P and K in protected fields were significantly increased compared with the open fields, but the pH value in the protected cultivation was lower than open cultivation, and that micronutrient contents did not differ much between the pairs except available Fe. However, the soil available Zn, Cu in the protected cultivation were higher compare to background value, and the soil available Zn, Cu are metal elements. So, feeding plants with fertilizer is an important consideration in this case.