【摘要】 在浙西北平原区和丘陵区分别选择传统施肥、施用化肥和施用商品有机肥等3种不同施肥方式的代表性梨园,进行为期一年的水果生产过程中有机肥、化肥、大气沉降、果实收获和地表径流中重金属流的定点定量观察分析,探讨梨园生态系统中重金属的年平衡值及其影响因素。结果表明,平原区梨园重金属的平衡值普遍高于丘陵区,平原区大气沉降对重金属输入的贡献高于丘陵区。梨园系统中多数重金属积累以施有机肥的最高,Cd主要以化肥方式进入梨园,Zn、Cu、Pb主要通过施有机肥方式进入梨园,而大气沉降对梨园中Zn、Pb、Hg和As积累也有较大的贡献。在丘陵区,传统施肥模式下,除Pb和As稍有积累外,梨园系统中其他重金属元素都呈现下降的趋势;化肥施肥模式下,Pb、Cd和As呈积累趋势,Zn、Cu和Hg呈现降低趋势;而有机肥施肥模式下,所有重金属元素均呈现积累趋势,并以Zn的积累量最高。在平原区,由于大气沉降输入的重金属较多,除传统施肥模式下的Cu和化肥施用模式下的Zn、Cu外,其他重金属元素都呈现积累趋势。更多还原

【Abstract】 Six typical pear orchards with different fertilization methods(traditional farmyard manure, chemical fertilizer and commercial organic fertilizer) in both plain and hilly regions of northwestern Zhejiang Province are selected to study the flows of Zn, Cu, Pb, Cd, Hg and As loaded by organic manure, chemical fertilizers,atmospheric deposition, pear harvest, and surface runoff in pear production system through one-year field monitoring. The annual mass balance values of the heavy metals in the pear orchard ecological system and their influencing factors are also discussed. The results showed that the balance values of heavy metals of the pear orchard in plain region were higher than those in hilly region. And the input contribution of heavy metals from atmospheric deposition in the plain region was higher than those in the hilly region. Annual accumulation of most of the heavy metals was the highest in the pear orchard applied with organic fertilizer. Cd was mainly from chemical fertilizer, meanwhile Zn, Cu and Pb were mainly from organic fertilizer. The atmospheric deposition also contributed greatly to the accumulation of Zn, Pb, Hg, and As. In the hilly region, for the pear orchard applied with traditional farmyard manure, Pb and As were slightly accumulated, and other heavy metals showed a decreasing trend. For the pear orchard applied with chemical fertilizer, Pb, Cd and As were accumulated,while Zn, Cu and Hg showed a decreasing trend. For the pear orchard applied with commercial organic fertilizer, all of the heavy metals were accumulated with the highest of Zn. Heavy metals in the pear orchards in plain regions, except Cu under conventional fertilization, and Zn and Cu under chemical fertilizer, showed an accumulation trend, due to more input of heavy metals from atmospheric deposition.更多还原