当前我国农业生产中的养分需求分析

Analyses on nutrient requirements in current agriculture production in China

【目的】估算当前我国不同区域农业生产中的养分需求和化肥需求,对如何实现2020年化肥零增长以及零增长下如何进行养分资源的合理分配、科学管理和施用具有重要的指导意义和参考价值。【方法】本研究依据国家统计最新数据、研究结果和文献资料,以省级为单元,系统估算了农作物、林地、草地、水产养殖全面实现平衡施肥条件下对氮磷钾养分的需求量。在考虑有机肥养分有效还田基础上,分析当前化肥消费量与化肥需求量的差异。【结果】当前我国农业生产需要氮磷钾养分共8410万t,其中N 3746万t、P_2O_5 2024万t、K_2O2640万t,粮食作物、蔬菜/瓜果、果树和茶叶、油料作物、纤维作物、糖料作物、饲草/草地、水产养殖的养分需求分别占总需求的41.8%、20.8%、13.1%、5.1%、2.3%、2.1%、10.6%和2.2%。华北、长江中下游、西北、西南、东南、东北地区的养分需求分别占20.3%、23.2%、18.8%、16.8%、11.1%和9.8%,其中山东、河南和四川对养分的需求高于其他省份。当前全国化肥消费量为6023万t,其中N、P_2O_5、K_2O分别为3001万t、1943万t和1079万t,东北、华北、长江中下游、东南、西南、西北地区的化肥消费量分别占全国化肥消费量的10.6%、27.7%、24.4%、11.5%、11.4%、14.2%。我国当前有机肥养分资源潜力为N 3200万t、P_2O_5 1440万t和K_2O 3400万t,但还田的有效养分约为N 484万t、P_2O_5 411万t和K_2O 1273万t。有机肥还田主要在河北、河南、山东、四川和湖南省,其次是广东、广西、云南,而西北、东北及东南沿海地区各省有机肥还田的有效养分量相对较少。化肥消费与需求差表明,全国氮肥和钾肥供应不足,分别亏缺约N 261万t和K_2O 288万t,而磷肥投入过量约P_2O_5 330万t。但不同省份和区域间化肥供需具有较大差异,东北、华北、长江中下游或东南地区的一些省份如吉林、河北、河南、山东、安徽、江苏、湖北、广东省氮磷钾肥均过量,而西北和西南地区多数省份的化肥投入不足。【结论】粮食作物是养分需求的主体,其次是蔬菜和果树。在全面实现平衡施肥的情况下,氮、钾肥投入不足,磷肥投入过量。养分需求地区间差异明显,东北、华北、长江中下游和东南沿海地区需适当减少肥料消费,而西北和西南地区需要依据需求适量增加肥料的投入。

【Objectives】Analyses of the nutrient requirements in current agricultural production and estimation of the chemical fertilizer demand in China will provide theoretical reference for the reliance of zero growth of chemical fertilizers by 2020,and also provide practical guide for rationally distribute,scientifically manage and apply nutrient resources under the situation of zero growth of chemical fertilizers.【Methods】Based on latest national statistical data,research data and literature review,this study made systematic estimation on N,P and K requirements by crops,forest,grassland and aquiculture under balance fertilization at a provincial level.The fertilizer gaps among fertilizer need and current consumption were also estimated considering recycle of available nutrients from organic sources.【Results】The current N,P_2O_5,K_2O requirements in China＇s agricultural production were 3746×10^4 t for N,2024×10^4 t for P_2O_5 and 2640×10^4 t for K_2O,respectively,with a total of8410×10^4 t.Grain crops,vegetables/melons,fruits/tea,oil crops,fiber crops,sugar crops,forage/grassland and aquiculture were accounted for 41.8%,20.8%,13.1%,5.1%,2.3%,2.1%,10.6% and 2.2% of total nutrient requirements,respectively.Northcentral（NC）,Middle and Lower Reaches of Yangzi River（MLRY）,Northwest（NW）,Southwest（SW）,Southeast（SE） and Northeast（NE） region were accounted for 20.3%,23.2%,18.8%,16.8%,11.1% and 9.8%,respectively,while nutrient requirements in Shandong,Henan and Sichuan were more than other provinces.Among the total nutrient consumption in China,chemical fertilizer was 6023×10^4 t including3001×10^4 t N,1943×10^4 t P_2O_5 and 1079×10^4 t K_2O;the consumption distribution in NE,NC,MLRY,SE,SW and NW was accounted for 10.6%,27.7%,24.4%,11.5%,11.4% and 14.2%,respectively.The organic nutrient capacity was 3200×10^4 t N,1440×10^4 t P_2O_5 and 3400×10^4 t K_2O,but the available nutrient returned to cropland was estimated to be 484×10^4 t N,411×10^4 t P_2O_5,1273×10^4 t K_2O.Organic nutrient return was mainly distributed in Hebei,Henan,Shandong,Sichuan and Hunan provinces,followed by Guangdong,Guangxi and Yunnan provinces,while relative small amount in NW,NE and SE regions.Gaps between fertilizer consumption and fertilizer demand indicated that N and K inputs were not enough as a whole in China,N and K_2O inputs were respectively in deficit of 261×10^4 t and 288×10^4 t,while P inputs were overused with 330×10^4 t P_2O_5 surplus.Great difference existed in fertilizer gaps among provinces and regions.In some provinces of NE,NC,MLRY or SE regions such as Jilin,Hebei,Henan,Shandong,Anhui,Jiangsu,Hubei and Guangdong provinces,N,P and K fertilizers were all overused,but fertilizer inputs in most provinces of NW and SW regions were insufficient.【Conclusions】Grain crops were the main nutrient demander,followed by vegetables and fruit trees.Under the hypothesis of balanced fertilization achieved in all crops and areas,nitrogen and potassium fertilizer inputs were insufficient,and phosphate fertilizer inputs were excessive.Great variations existed among regions in nutrient requirement.The NE,NC,MLRY and SE coastal areas need to appropriately reduce fertilizer consumption and the NW and SW regions need to appropriately increase fertilizer inputs based on nutrient requirements.