乌龙茶专用肥的农学、经济和环境效应评价

针对铁观音茶园施肥过量问题,于2018—2019年在安溪县布置4季田间试验,分析农民习惯、优化施肥以及乌龙茶专用肥对铁观音产量、品质、养分吸收和环境代价的影响。结果显示：（1）与农民习惯施肥相比,优化施肥处理的产量、经济效益、新梢氮磷钾的养分浓度和养分带走量以及茶叶品质无显著差异;乌龙茶专用肥处理较优化施肥处理显著增加了芽密度。（2）与农民习惯施肥相比,优化施肥处理的氮、磷、钾肥料偏生产力分别提高了63.8%、112.4%、106.6%,乌龙茶专用肥处理的氮、磷、钾肥料偏生产力分别提高72.3%、123.3%、117.3%。（3）优化施肥处理的氮、磷、钾肥表观盈余量较农民习惯施肥分别减少了48.0%、58.0%、65.8%,乌龙茶专用肥处理的氮、磷、钾肥表观盈余量较农民习惯施肥分别减少48.8%、58.0%、65.8%。（4）与农民习惯施肥相比,优化施肥处理的单位产量的活性氮损失、温室气体排放、酸化效应、富营养化效应的平均降低幅度分别为37.6%、36.1%、37.5%、37.7%,乌龙茶专用肥平均降低幅度分别为42.4%、41.0%、42.3%、42.5%。减肥情况下茶叶产量、芽密度和百芽重均未受到影响,且在保证茶叶养分吸收利用、品质、经济效益的基础上,提高肥料利用率,降低氮磷钾养分的表观盈余和环境代价。此外,加镁显著提高茶芽密度,对实现铁观音茶叶的绿色生产具有重要的现实意义。

Evaluation of Agronomic,Economic and Environmental Effects of Special Fertilizer on Oolong Tea

To solve the problem of excessive fertilization input in Tie Guanyin tea garden, a field experiment was conducted in Anxi County to analyze the effects of different fertilization modes (farmers’ practice, optimized fertilization and special fertilizer treatment) on yield, quality, nutrient absorption and environmental cost of Tie Guanyin tea garden from 2018 to 2019. The results showed that: (1) compared with the farmers’ practice (FP), the yield, economic benefit, NPK concentration of young shoot and nutrient take away amount of the optimized fertilization (Opt-_NPK) had no significant difference, the special fertilizer treatment (SF) of oolong tea significantly increased bud density compared with the optimized fertilization treatment; (2) compared with the FP treatment, the partial productivity of NPK fertilizers in the Opt-_NPK treatment increased by 63.8%, 112.4% and 106.6%, respectively, and that of SF treatment increased by 72.3%, 123.3% and 117.3%, respectively; (3) the apparent surplus of NPK fertilizers in the Opt-_NPK treatment was reduced by 48.0%, 58.0% and 65.8% compared with the FP treatment, respectively, the apparent surplus of NPK fertilizers in the SF treatment was reduced by 48.8%, 58.0% and 65.8% compared with the FP treatment, respectively; (4) compared with the FP treatment, the environmental impacts were also significantly reduced, for the per unit output of Opt-_NPK treatment, the reactive N loss, greenhouse gas emission, acidification and eutrophication averagely decreased by 37.6%, 36.1%, 37.5% and 37.7%, respectively, and those of special fertilizer treatment averagely decreased by 42.4%, 41.0%, 42.3% and 42.5%, respectively. Reducing the amount of fertilizer has no effect on the yield, bud density and hundred bud weight of tea, in addition, it could guarantee of the stable absorption and utilization of nutrients, tea quality and economic benefits, and increase the fertilizer utilization rate and decrease the apparent surplus of NPK nutrients and environmental cost. Meanwhile, the application of magnesium could improve tea bud density, which was effective to the sustainable development of Tie Guanyin tea.