中国玉米百千克籽粒地上部吸氮量的空间差异及驱动因素  

Spatial Differences and Driving Factors of Aboveground Nitrogen Uptake in Per Hundred Kilograms Grain of Maize in China

作　　者：王丹丹 陈焕轩 张翀 巨晓棠 WANG DanDan;CHEN HuanXuan;ZHANG Chong;JU XiaoTang(College of Tropical Agriculture and Forestry,Hainan University,Haikou 570228)

机构地区：[1]海南大学热带农林学院,海口570228

出　　处：《中国农业科学》2023年第20期3996-4009,共14页Scientia Agricultura Sinica

基　　金：海南省重点研发计划(ZDYF2021XDNY184);海南省重大科技计划(ZDKJ2021008);海南省自然科学基金(422RC597);海南大学启动经费(KYQD(ZR)-20098)。

摘　　要：【目的】定量中国不同农业生态区和不同产量水平条件下的玉米百千克籽粒地上部吸氮量(N_(100)),分析气候、土壤、品种和施肥因素对玉米N_(100)的影响,为确定合理施氮量提供科学依据。【方法】将中国分为东北、西北、华北平原、长江中下游平原、西南和东南6大农作区,搜集1980—2022年发表的349篇符合要求的文献,通过数据统计分析不同区域和不同产量水平条件下的玉米N_(100),并分析采用统一和区域化的N_(100)计算出的理论施氮量差异,采用皮尔逊相关系数(pearson correlation coefficient)、随机森林(random forest)模型和整合分析(Meta-analysis)方法分析气候、土壤和施肥因素对玉米N_(100)的影响,揭示导致中国玉米N_(100)空间差异的原因。【结果】优化处理条件下,中国春玉米N_(100)显著低于夏玉米,分别为2.21和2.46;不同农业生态区玉米N_(100)存在显著差异,分别为2.19(东北春玉米)、2.12(西北春玉米)、2.54(西北夏玉米)、2.45(华北夏玉米)、2.77(长江中下游春玉米)、2.38(长江中下游夏玉米)和2.39(西南玉米区)。依据本研究全国玉米平均N_(100)(2.34)计算的理论施氮量与采用区域化的N_(100)计算得到的理论施氮量相差-22—31 kg N·hm^(-2)。地上部吸氮量、产量、年均气温是影响玉米N_(100)的最重要因素;N_(100)随产量增加呈显著二次曲线降低的趋势(P<0.01),籽粒产量可以很好地预测N_(100);品种显著影响玉米N_(100),中国常见的玉米品种郑单958、先玉335和登海605的N_(100)分别为2.42、2.12和2.39,新品种玉米N_(100)显著低于老品种。施用氮肥显著增加了玉米N_(100),且在施氮量200—300 kg N·hm^(-2)时,施氮肥引起的N_(100)增加效应最大。单施缓控释肥、深施氮肥、减少氮肥基施比例以及增加施氮次数均显著增加了玉米N_(100)。【结论】在利用N_(100)进行合理施氮量计算时,需要考虑不同农业生态区N_(100)的显�【Objective】We aim to quantify aboveground nitrogen(N)uptake in per hundred kilograms grain(N_(100))of maize in different agro-ecological zones at different yield levels in China,and analyze the effects of climate,soil,variety and N fertilization on N_(100) of maize,thus to provide a scientific basis for determining rational N fertilizer rate.【Method】We divided Chinese cropland into six major regions,i.e.,northeast,northwest,North China Plain,middle and lower Yangtze River,southwest,and southeast,and collected 349 peer-reviewed papers published during 1980-2022 to analyze the spatial variation of N_(100) and its changes at different yield levels,and compared the differences in calculated theoretical N rate between constant and region-specific N_(100).The effects of climate,soil and fertilization on N_(100) were analyzed using Pearson correlation coefficient,Random forest model and Meta-analysis,to reveal the causes of spatial variation in N_(100).【Result】Under the optimized N management,N_(100) of spring maize was significantly lower than that of summer maize which were 2.21 and 2.46,respectively;and there were significant differences in N_(100) of maize among different agro-ecological zones,which were 2.19(Northeast spring maize),2.12(Northwest spring maize),2.54(Northwest summer maize),2.45(North China Plain summer maize),2.77(Middle and Lower Yangtze River spring maize),2.38(Middle and Lower Yangtze River summer maize),and 2.39(Southwestern maize zone),respectively.The difference between calculated the theoretical N rate based on the national average N_(100)(2.34)and that based on regional-specific N_(100) was-22-31 kg N·hm^(-2).Aboveground N uptake,yield,and mean annual temperature were the most important factors affecting N_(100).The N_(100) showed a significant quadratic decrease with increasing yield(P<0.01),and grain yield was a good predictor of N_(100).Varieties significantly affected maize N_(100),the N_(100) of common Chinese maize varieties Zhengdan 958,Xianyu 335,and Denghai 605 are 2.42

关 键 词：玉米 百千克籽粒地上部吸氮量 产量水平 合理施氮量 农业生态区 

分 类 号：S513[农业科学—作物学]