摘要
通过田间试验研究了不施肥（CK）、施氮360 kg·hm^-2（T1）、施氮720 kg·hm^-2（T2）处理下茶园土壤无机氮、p H、各形态氟含量的动态变化和春、夏、秋茶树新梢一芽四叶、一芽五叶氟含量,探讨茶园施氮对土壤和茶树新梢氟含量的影响。结果表明：1）茶园施氮后短期内（20-30 d）土壤水溶态氟含量显著降低,土壤交换态氟和铁锰结合态氟含量降低;长期（45-50 d）土壤水溶态氟含量的降低作用减弱,土壤交换态氟和铁锰结合态的含量增加;在试验结束时（164 d）,与CK处理相比,T1处理0-20 cm土壤各形态氟含量降低,T2处理0-20 cm土壤各形态氟含量增加。2）0-20 cm茶园土壤水溶态氟、铁锰结合态氟与NH4^＋-N分别呈极显著负、正相关（P〈0.01）,20-40 cm土壤水溶态氟、交换态氟与NO3^--N分别呈极显著正、负相关（P〈0.01）。土壤p H与土壤水溶态氟含量极显著负相关（P〈0.01）,与其他3种形态氟含量相关性不显著。土壤铁锰结合态氟与交换态氟、有机结合态氟呈显著、极显著正相关,但与土壤水溶态氟均无显著相关性。3）春茶前后施氮可以降低春、夏、秋茶树新梢一芽四叶、一芽五叶氟含量,但未达显著水平。T1处理新梢氟含量的降低值为夏茶（25.15-27.95 mg·kg^-1）〉秋茶（21.06-24.31 mg·kg^-1）〉春茶（18.58-21.03 mg·kg^-1）,T2处理的降低值为秋茶（18.64-22.34 mg·kg^-1）〉夏茶（7.79-14.14 mg·kg^-1）〉春茶（3.52-7.30 mg·kg^-1）。春、夏、秋茶树新梢氟含量主要受0-20 cm土壤无机氮和20-40 cm土壤p H的影响。因此推测施氮通过影响茶树根系氟的吸收和氟在叶片中的累积过程调控茶树新梢氟含量,该研究成果为合理利用施氮技术降低茶园土壤和茶树新梢氟含量提供了理论依据。
A field experiment was conducted to determine the effects of nitrogen（N） fertilization on fluorine（F） contents in tea garden soils and tea shoots. The rates of nitrogen application were respectively 0 kg（N） ·hm^-2（CK）, 360 kg（N） ·hm^-2（T1）and 720 kg（N）·hm^-2（T2）. The dynamic changes of soil p H and contents of NH4^＋-N, NO3^--N and F in different forms in tea garden soil were studied and F contents of shoots with one bud and four leaves, and shoots with one bud and five leaves were measured in spring, summer and autumn, respectively. The results showed that： 1） N application significantly decreased the content of water soluble F（FW） and slightly decreased the content of exchangeable F（FEx） and Fe/Mn oxide-bound F（FFe/Mn）in tea garden soil in 20 to 30 days after N application. In 45 -50 days after N fertilization, the reduction in Fwslowed down while the contents of FEx and FFe/Mn increased. Compared with CK, the contents of various forms F in the 0 -20 cm soil layer decreased under T1 treatment, while they increased under T2 treatment at the end of the experiment 164 days after N application. 2） Correlation analyses showed that for the 0 - 20 cm soil layer, NH4＋-N content was significantly negativelycorrelated with Fw and positively correlated with FFe/Mn（P〈0.01）. Then for the 20 - 40 cm soil layer, NO3^--N content was significantly positively correlated with FW and negatively correlated with FEx（P〈0.01）. Soil p H had a significantly negative correlation with FW（P〈0.01）, but no significant correlation with the other three forms of F. FFe/Mn was significantly positively correlated with FEx and organic matter-bound F（FOr） at P〈0.01, but no significantly correlated with FW. 3） N application before and after spring tea harvest reduced F content in new shoots with one bud and four leaves and shoots with one bud and five leaves in spring, summer and autumn. However, the effect was not significant among different treatments. Under T1 condition, the largest reduction in F content in tea shoots was in summer tea（25.15-27.95 mg·kg^-1）, followed by autumn tea（21.06-24.31 mg·kg^-1） and spring tea（18.58 - 21.03 mg · kg^ 1）. Under T2 condition, the largest reduction in F content in tea shoots was in autumn tea（18.64-22.34 mg·kg^-1）, followed by summer tea（7.79-14.14 mg·kg^-1） and then spring tea（3.52-7.30 mg·kg^-1）. F content in tea shoots was mainly affected by soil inorganic N in the 0-20 cm soil layer and by soil p H in the 20-40 cm soil layer. N application influenced tea root absorption of F and tea leaf accumulation of F, which regulated F content in new tea shoots. The study laid the theoretical basis for N fertilizing management in order to reduce F content in tea garden soils and in tea shoots.
出处
《中国生态农业学报》
CAS
CSCD
北大核心
2015年第12期1562-1570,共9页
Chinese Journal of Eco-Agriculture
基金
现代农业产业技术体系建设专项资金(CARS-23-01A)
安徽省农业科学院院长青年创新基金项目(13B0839)资助~~
关键词
氮肥
茶园土壤
茶树新梢
氟形态
铵态氮
硝态氮
土壤pH
Nitrogen fertilizer
Tea garden soil
Tea shoot
Fluorine form
Ammonium nitrogen
Nitrate nitrogen
Soil pH
