Information about the behavior and temporal evolution of heavy metals in agricultural soils is limited, particularly about greenhouse soils on semiarid lands, indeed it nonexistent. Western Almería (Southern Spain) is a semiarid land where some 30,000 ha are occupied by greenhouses with high productivity. As these greenhouses are fundamental to the socioeconomic development of this area, they should be maintained and well conserved. However, there are indications that long‐term intensive agriculture with considerable agrochemicals use can deteriorate soil quality, which in turn, would reduce productivity and food quality. This study was conducted to investigate soil contamination and the temporal trends of heavy metal concentrations in greenhouse soils of western Almería. Contamination level, availability, and sources of metals were evaluated by the extractable fraction percentage, by indices zinc equivalent, geoaccumulation, enrichment factor and pollution load, and by a correlation analysis between soil properties and metal contents. The results showed that the total contents of Cd, Cu, Ni, and Pb, and the available concentration of Cd, Cu, Pb, and Zn, were significantly higher than background levels. Temporal patterns indicated that these elements accumulate in greenhouse soils. After more than 20 years of intensive agriculture, the available concentration of elements, and contamination, had clearly increased.

中文翻译：

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评估半干旱地区温室土壤污染和重金属含量的时空变化趋势

关于农业土壤中重金属的行为和时间演变的信息是有限的，特别是关于半干旱土地上的温室土壤的信息，实际上是不存在的。西部的阿尔梅里亚（西班牙南部）是半干旱的土地，约有30,000公顷的温室被高生产率的温室所占据。由于这些温室对于该地区的社会经济发展至关重要，因此应予以维护和妥善保存。但是，有迹象表明，长期大量使用农药的集约化农业会恶化土壤质量，从而降低生产力和食品质量。这项研究旨在调查西部阿尔梅里亚温室土壤中的土壤污染和重金属含量的时空趋势。污染程度，可用性，金属的来源通过可提取的分数百分比，锌当量，地积累，富集因子和污染负荷等指标进行评估，并通过土壤性质与金属含量之间的相关分析进行评估。结果表明，Cd，Cu，Ni和Pb的总含量以及Cd，Cu，Pb和Zn的有效浓度均显着高于背景水平。时间模式表明这些元素在温室土壤中积累。经过20多年的集约化农业，元素的有效浓度和污染明显增加。Cu，Ni和Pb以及Cd，Cu，Pb和Zn的有效浓度均显着高于背景水平。时间模式表明这些元素在温室土壤中积累。经过20多年的集约化农业，元素的有效浓度和污染明显增加。Cu，Ni和Pb以及Cd，Cu，Pb和Zn的有效浓度均显着高于背景水平。时间模式表明这些元素在温室土壤中积累。经过20多年的集约化农业，元素的有效浓度和污染明显增加。