施氮对关中地区冬小麦农田土壤呼吸的影响及基于植被指数的估算模型

王锐; 蔡焕杰; 王晓云; 赵政鑫; 田雅洁; 彭青

王锐,蔡焕杰,王晓云,赵政鑫,田雅洁,彭青.施氮对关中地区冬小麦农田土壤呼吸的影响及基于植被指数的估算模型[J].干旱地区农业研究,2023,(6):97~106

施氮对关中地区冬小麦农田土壤呼吸的影响及基于植被指数的估算模型

Effects of nitrogen fertilizer application on soil respiration in winter wheat fields in Guanzhong region and estimation model based on vegetation index

DOI：10.7606/j.issn.1000-7601.2023.06.11

中文关键词: 冬小麦土壤呼吸施氮量估算模型植被指数关中地区

英文关键词:winter wheat soil respiration nitrogen fertilizer application amount estimation model vegetation index Guanzhong region

基金项目:国家自然科学基金项目(52179046)

作者	单位
王锐	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100
蔡焕杰	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100
王晓云	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100
赵政鑫	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100
田雅洁	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100
彭青	西北农林科技大学水利与建筑工程学院，陕西杨凌 712100；西北农林科技大学中国旱区农业节水研究院，陕西杨凌 712100

摘要点击次数: 677

全文下载次数: 540

中文摘要:

为探寻不同施氮量对农田土壤呼吸（R_S）的影响并快速准确估算R_S，以关中地区冬小麦为研究对象，观测了5种施氮量下冬小麦农田R_S的变化，研究了环境因子（土壤温度、土壤湿度）及作物因素（叶面积指数、地上部生物量、SPAD值）对于R_S的影响，建立了适用于关中地区土壤温度与植被指数下的农田土壤呼吸估算模型。设置秸秆还田下的5种施氮量处理，分别为传统施氮量SN200（200 kg·hm^-2）、优化施氮量SN150（150 kg·hm^-2）、60%优化施氮量SN120（120 kg·hm^-2）、50%优化施氮量SN100（100 kg·hm^-2）以及不施氮肥SN0（0 kg·hm^-2）。结果表明：不同施氮量下R_S随生育期推进均表现为先升高再降低的趋势，同时添加氮肥促进了R_S排放。各处理观测期内R_S的均值为：SN200（3.68 μmol·m^-2·s^-1）>SN150（3.40 μmol·m^-2·s^-1）>SN120（3.06 μmol·m^-2·s^-1）>SN100（2.70 μmol·m^-2·s^-1）>SN0（2.21 μmol·m^-2·s^-1）。不同施氮量下冬小麦冠层近红外波段反射率在拔节期和抽穗期差异明显，反射率从高到低依次为SN200>SN150>SN120>SN100>SN0，而在灌浆期和成熟期差异不大。土壤温度显著影响了R_S（P<0.01），土壤湿度与R_S没有显著相关关系（P0.05）。叶面积指数、地上部生物量、SPAD值和植被指数均与R_S呈显著相关关系（P<0.05）。通过多种模型评估，建立基于植被指数和土壤温度的最佳农田土壤呼吸估算模型，显著高于基于土壤温度的单因子模型，模型精度可达到0.6以上（n=120）。

英文摘要:

In order to explore the effects of different nitrogen application rates on farmland soil respiration (R_S) and quickly and accurately estimate R_S, this study took winter wheat in Guanzhong area as the research object, observed the changes of R_S under five nitrogen application rates, and examined the effects of environmental factors (soil temperature and soil moisture) and crop factors (leaf area index, above\|ground biomass, SPAD) on R_S. An estimation model of farmland soil respiration based on soil temperature and vegetation index was established in Guanzhong area. The experiment was set as five nitrogen application rates under straw returning. They were conventional nitrogen application SN200 (200 kg·hm^-2), optimal nitrogen application SN150 (150 kg·hm^-2), 60% optimal nitrogen application SN120 (120 kg·hm^-2), 50% optimal nitrogen application SN100 (100 kg·hm^-2) and no nitrogen application SN0 (0 kg·hm^-2). The results showed that R_S increased first and then decreased with the growth period under different nitrogen application rates, and the addition of nitrogen promoted R_S emission. The mean value of R_S in each treatment observation period was: SN200 (3.68 μmol·m^-2·s^-1) > SN150 (3.40 μmol·m^-2·s^-1) > SN120 (3.06 μmol·m^-2·s^-1) > SN100 (2.70 μmol·m^-2·s^-1) > SN0 (2.21 μmol·m^-2·s^-1). The near\|infrared reflectance of winter wheat canopy at jointing stage and heading stage was significantly different under different nitrogen application rates, and the reflectance from high to low was SN200>SN150>SN120>SN100>SN0, while the difference was not significant at filling stage and maturity stage. Soil temperature significantly affected R_S (P<0.01), but soil moisture had no significant correlation with R_S (P0.05). Leaf area index, aboveground biomass, SPAD and vegetation index were significantly correlated with R_S (P<0.05). Through multiple model evaluation, the optimal farmland soil respiration estimation model based on vegetation index and soil temperature was established, which was significantly higher than the single factor model based on soil temperature, and the accuracy of the model could reach more than 0.6 (n=120).

查看全文查看/发表评论下载PDF阅读器