摘要
不同农作体系施肥措施差异引起的土壤环境质量变化 ,会进一步影响该体系的生产力并对大气和水体环境产生潜在影响。选取中国北方两种重要的集约化种植体系 (大棚蔬菜和小麦 -玉米轮作体系 ) ,研究了经过长期施肥后 ,0～ 30 cm土壤有机质、全氮、微量元素与重金属的差异以及 0～ 90 cm土壤剖面的硝态氮、铵态氮、速效磷、速效钾、p H和电导率的变化。结果表明 ,大棚菜地氮、磷、钾化肥投入量达 N 2 82 3、P 92 8和 K 92 5 kg/(hm2 · a) ,分别为小麦 -玉米轮作农田的 4 .7、10 .1和 2 3.4倍。大棚菜地还施用了大量的有机肥。菜地土壤养分大量积累 ,尤其是硝态氮和速效磷 ,0～ 90 cm土层二者分别达 1389.8kg N/hm2和 132 1.1kg P/hm2 ,为农田的 5 .6和 8.4倍。速效钾和铵态氮累积量分别为 1817.3kg K/hm2 和 10 0 .4 kg N/hm2 ,为农田的2 .2倍和 1.8倍。同时 ,大棚菜地土壤中的养分还存在严重的淋溶现象。大棚菜地有机质、全氮和有效铁、锰、铜、锌含量分别为农田的 1.3、1.4、1.2、1.3、1.3和 1.4倍。镉含量为农田的 3.8倍。镉与土壤速效磷含量呈显著正相关 ,可见 ,磷肥的大量投入是镉在土壤中累积的主要原因。大棚菜地各层土壤 p H均明显低于农田相应土层 p H,而 0～ 30 cm和 30～ 6 0
Changes of soil quality caused by different fertilization under different cropping systems may affect the production, and potentially air and water quality. This paper investigated the differences of OM, total N, microelements and heavy metals in 0～30cm soil layer and NO^-_3-N, NH^+_4-N, available P and K, pH and electrical conductivity in 0～90 cm soil profile after long-term different fertilization in two cropping systems, rotation of wheat and corn and plastic greenhouse vegetable in north China. The results showed that the chemical fertilizer rates for N, P and K applied to vegetable fields were as high as 2823, 928 and 925 kg/(hm^2·a), being 4.7, 10.1 and 23.4 folds of that applied to wheat-corn system, respectively. In addition, large amount of organic fertilizer was applied to protected vegetable. A great amount of nutrients accumulated in the vegetable soil, especially NO^-_3-N and available P which amounted to 1389.8 kg N/hm^2 and 1321.1 kg P/hm^2 in 0～90cm soil layer and were 5.6 and 8.4 times of that in wheat-corn soil, respectively. Available K and NH^+_4-N accumulated in 0～90cm soil layer amounted to 1817.3 kg K/hm^2 and 100.4 kg N/hm^2 and were only 2.2 and 1.8 times of that in wheat-corn soil. Nutrients accumulated in vegetable soil were also seriously leached down to deep soil layer. The other nutrients, OM, total N and available Fe, Mn, Cu and Zn accumulated in the soil of plastic greenhouse were only 1.3, 1.4, 1.2, 1.3, 1.3 and 1.4 folds of those in wheat-corn field. Soil concentration of Cd in vegetable field was 2.8 folds of that in wheat-corn field. The significantly positive correlation of soil concentration of Cd with available P meant that large application dose of P fertilizer may be the source of Cd accumulated in soil. Soil pH in vegetable field was lower than wheat-corn field in all 3 layers, while the electrical conductivity was higher in 0～30cm and 30～60cm soil layers. Obvious soil acidification and severe accumulation of salt was observed, especially in 0～30cm soil layer in vegetable field. Soil electrical conductivity was positively correlated with nitrate content, while pH decreasingly related with nitrate with power function, and this indicted that accumulation of NO^-_3-N in soil was the main factor inducing soil salinization and acidification.
出处
《生态学报》
CAS
CSCD
北大核心
2004年第11期2548-2556,共9页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 ( 3 0 2 70 787和 3 0 3 90 0 81)
国家十五攻关重大专项资助项目 ( 2 0 0 2 BA5 16A0 2 )~~
关键词
大棚蔬菜
小麦-玉米轮作
养分累积
电导率
pH
微量元素
重金属
plastic greenhouse vegetable
wheat-corn rotation system
nutrient accumulation
electrical conductivity
pH
micronutrients
heavy metal
