| 施肥和秸秆覆盖对成都平原区农田氮和磷流失的影响 |
| 摘要点击 2753 全文点击 2924 投稿时间：2022-03-30 修订日期：2022-05-13 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 成都平原 湿沉降 地表径流 养分流失 面源污染 |
| 英文关键词 Chengdu Plain wet deposition surface runoff nutrient loss non-point source pollution |
|
| 中文摘要 |
| 近年来由于氮、磷肥料过量施用造成了严重的污染问题和富营养化现象，而且这种污染问题在稻田区域更加明显.因此，采用田间小区试验方法，通过对2018年和2019年田间实地监测，在自然降雨条件下，对成都平原区不同施肥量以及秸秆覆盖对湿沉降和地表径流氮和磷的影响进行研究.结果表明，湿沉降氮养分主要以铵态氮存在，磷养分主要以可溶性总磷存在，氮和磷沉降主要发生在6~8月这3个月.地表径流量与降雨量呈正比，而地表径流氮养分浓度与降雨量呈反比.在2018年和2019年，增氮处理TR3总氮流失量分别为4.75 kg ·hm-2和2.68 kg ·hm-2，比常规处理TR1流失量增加26.73%和43.32%，是流失量最高的处理；减氮处理TR4总氮流失量分别为2.91 kg ·hm-2和1.37 kg ·hm-2，比常规处理TR1流失量降低了36.33%和26.74%，是流失量最小的处理.优化施肥处理TR2和减氮处理TR4能够有效降低地表径流磷素的流失，集中高强度降雨会降低地表径流总磷中颗粒态磷的含量.氮养分的流失主要集中于7~9月这3个月，而磷养分的流失主要集中在7月之前.因此，成都平原区，通过在施肥初期和雨季使用平衡施肥和减肥措施控制氮和磷的流失，能够有效地降低成都平原地区农田面源污染现象. |
| 英文摘要 |
| In recent years, the excessive application of nitrogen and phosphorus fertilizers has caused serious pollution and eutrophication, especially in paddy fields. Accordingly, a two-year (2018-2019) study was conducted at a rice paddy field under different fertilizer application rates and straw mulching in Chengdu Plain. N and P losses through the rainfall and surface runoff in the paddy field were measured under natural rainfall conditions. The results showed that nitrogen mainly existed in the form of ammonium nitrogen, and phosphorus mainly existed in the form of soluble phosphorus in the wet deposition. The wet deposition of nitrogen and phosphorus mainly occurred in June, July, and August. Surface runoff was positively correlated with rainfall, whereas surface runoff nitrogen concentration was inversely correlated with rainfall. The highest runoff losses of TN (4.75 kg·hm-2 in 2018 and 2.68 kg·hm-2 in 2019) were produced by TR3 practice and were 26.73% and 43.32% higher than that of the conventional practice. TN runoff loss was significantly decreased by reducing the rate of N fertilizer (P<0.05). Compared with that in the conventional practice TR1, TR4 reduced the N loss by 36.33% in 2018 and 26.74% in 2019, respectively. Optimized fertilizer TR2 and nitrogen reduction practice TR4 decreased P loss from surface runoff, and high intensity rainfall could reduce the content of granular phosphorus in surface runoff. The surface runoff occurring in July, August, and September contributed mostly to the total N loss, whereas the loss of total P mainly occurred before July. Consequently, the use of balanced fertilizer and decreased nitrogen fertilization amount might be effective strategies to attenuate non-point source pollution in the Chengdu Plain in the paddy fields. |
|
|
|
