长期不同施肥红壤磷素变化及其对产量的影响

doi:10.3864/j.issn.0578-1752.2019.21.012

摘要/Abstract

摘要：

目的定量长期不同施肥红壤磷素的演变特征,研究红壤磷素变化对生产力的影响,为红壤地区磷素管理提供理论依据。方法利用持续26年的红壤旱地长期定位试验平台（1991—2016年）,比较长期不施磷肥（CK、N、NK）、施用化学磷肥（PK、NP、NPK）、化肥配合秸秆还田（NPKS）和化肥配施有机肥及有机肥（1.5NPKM、NPKM、M）土壤Olsen-P和全磷含量变化,分析土壤磷素对磷盈亏量的响应,采用不同模型拟合作物产量对有效磷的响应曲线,计算土壤有效磷农学阈值。结果长期施用磷肥显著提高了土壤全磷和有效磷含量,提升了土壤磷素活化系数（PAC）。化肥配施有机肥及有机肥处理（1.5NPKM、NPKM、M）的PAC高于化肥配合秸秆还田（NPKS）和施用化学磷肥（PK、NP、NPK）。红壤地区土壤全磷和有效磷变化量与土壤磷盈亏量呈正相关关系（P＜0.01）,土壤每累积盈余100 kg P·hm ^-2,土壤Olsen-P含量上升3.00—5.22 mg·kg ^-1,全磷上升0.02—0.06 g·kg ^-1。土壤每累积亏缺磷100 kg P·hm ^-2,不施磷肥处理（CK、N、NK）土壤Olsen-P分别下降1.85、0.40、1.76 mg·kg ^-1。化肥配施有机肥及有机肥处理（1.5NPKM、NPKM、M）的小麦和玉米产量显著高于化肥配合秸秆还田（NPKS）以及施用化学磷肥（PK、NP、NPK）,显著高于不施磷肥（CK、NK、N）。化肥配施有机肥及有机肥处理（1.5NPKM、NPKM、M）的产量可持续指数也高于其他处理。3种模型（线性-线性模型、线性-平台模型和米切里西方程）均能较好地拟合作物产量与红壤有效磷含量的响应关系（P＜0.01）。在红壤地区推荐使用拟合度较好的线性-线性模型,其计算出小麦和玉米的土壤Olsen-P农学阈值分别为13.5和23.4 mg·kg ^-1。结论在南方红壤地区,化肥配施有机肥更有利于磷素累积和提升磷素有效性。化肥配施有机肥作物产量显著高于其他处理,且稳产性好。线性-线性模型可用于计算红壤地区有效磷的农学阈值。生产上应该根据土壤有效磷含量及其农学阈值调整磷肥施用量。

关键词: Olsen-P, 全磷, 相对产量, 磷素活化系数, 磷盈亏, 磷素农学阈值, 长期施肥, 红壤

Abstract:

【Objective】 Change characteristic of phosphorus (P) in red soil were quantified under long term different fertilizations, and effects of P on soil productivity were studied, so as to provide a theoretical basis for P management in red soil regions in southern China. 【Method】 Change of soil Olsen-P and total P content was compared under long term no P fertilization (CK, N, NK), chemical P fertilizer (PK, NP, NPK), application of chemical fertilizer combined with half crop straw return (NPKS) and application of organic manure and chemical fertilizer combined with organic manure (1.5NPKM, NPKM, M) using long term trial platform in the upland red soil (from 1991-2016). Responses of soil P to P balance were analyzed. Different models were used to fit the response curve of crops yield to Olsen-P in the red soil. The critical P value of soil Olsen-P for crop yield (CV) was calculated. 【Result】 The Olsen-P and total P increased, and P activation coefficient (PAC) promoted under long term P fertilization in the red soil. PAC was higher under application of organic manure and chemical fertilizer combined with organic manure (1.5NPKM, NPKM, M) than that under application of chemical fertilizer combined with half crop straw return (NPKS) and chemical P fertilizer (PK, NP, NPK). Changes of Olsen-P and total P were significantly affected by P balance (P＜0.01). Soil Olsen-P increased by 3.00-5.22 mg·kg ^-1, and total P increased by 0.02-0.06 g·kg ^-1 with 100 kg P·hm ^-2 cumulative surplus in the red soil. The Olsen-P decreased with years under long term no P fertilization (CK, N, NK), and they decreased by 1.85 mg·kg ^-1, 0.40 mg·kg ^-1, and 1.76 mg·kg ^-1, respectively, with 100 kg P·hm ^-2 cumulative deficiency in the red soil. Grain yields of wheat and maize were significant higher under application of organic manure and chemical fertilizer combined with organic manure (1.5NPKM, NPKM, M) than that under application of chemical fertilizer combined with half crop straw return (NPKS) and chemical P fertilizer (PK, NP, NPK) than under no P fertilizations (CK, N, NK). Sustainability index of grain yield (SYI) were higher under application of organic manure and chemical fertilizer combined with organic manure (1.5NPKM, NPKM, M) than that under the other treatments. Three models (linear-linear model, linear-platform model and Michelice model) were better fit the response of crop yield to Olsen-P in red soil (P＜0.01). Linear-linear model was recommended for the higher R ². The critical value of Olsen-P content in agronomic in red soil of wheat and maize were 13.5 mg·kg ^-1, and 23.4 mg·kg ^-1, respectively, calculated by linear-linear mode. 【Conclusion】 Application of chemical fertilizer combined with organic manure were recommended in red soil region of southern China. That had the beneficial for P accumulation and promoting P availability. Applications of chemical fertilizer combined with organic manure were also used to keep the high and stable production. Linear-linear model was recommended to calculate the critical value of Olsen-P content in agronomic. Application rates of P fertilizer should be adjusted timely according to the difference between actual Olsen-P content in the soil and critical value of Olsen-P content in agronomic in productivity.

Key words: Olsen-P, total P, relative yield, PAC, P balance, critical value of Olsen-P content in agronomic, long-term fertilization, red soil

李冬初,王伯仁,黄晶,张杨珠,徐明岗,张淑香,张会民. 长期不同施肥红壤磷素变化及其对产量的影响[J]. 中国农业科学, 2019, 52(21): 3830-3841.

LI DongChu,WANG BoRen,HUANG Jing,ZHANG YangZhu,XU MingGang,ZHANG ShuXiang,ZHANG HuiMin. Change of Phosphorus in Red Soil and Its Effect to Grain Yield Under Long-Term Different Fertilizations[J]. Scientia Agricultura Sinica, 2019, 52(21): 3830-3841.

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处理 Treatment	玉米季Maize		小麦季Wheat
处理 Treatment	化肥 Mineral fertilizer (kg·hm^-2)	猪粪鲜重 Swine manure (t·hm^-2)	化肥 Mineral fertilizer (kg·hm^-2)	猪粪鲜重 Swine manure (t·hm^-2)
CK	0-0-0	0	0-0-0	0
N	210-0-0	0	90-0-0	0
NP	210-84-0	0	90-36-0	0
NK	210-0-84	0	90-0-36	0
PK	0-84-84	0	0-36-36	0
NPK	210-84-84	0	90-36-36	0
NPKM	63-84-84	29.4	27-36-36	12.6
1.5NPKM	95-126-126	44.1	40-54-54	18.9
NPKS	210-84-84	1/2秸秆还田 1/2 crop straw return	90-36-36	1/2秸秆还田 1/2 crop straw return
M	0-0-0	42	0-0-0	18

处理 Treatments	小麦产量 Grain yield of wheat (kg·hm^-2·a^-1)	产量可持续指数 SYI	玉米产量 Grain yield of maize (kg·hm^-2·a^-1)	产量可持续指数 SYI	年总产量 Grain yield annually (kg·hm^-2·a^-1)	产量可持续指数 SYI
CK	332.2±135.0 C	0.32	241.7±207.5 F	0.04	573.9±287.5E	0.23
N	275.5±392.8 C	-0.09	578.4±721.3 F	-0.05	853.9±1079.6E	-0.06
NP	774.3±584.4 B	0.09	1438.5±1254.1E	0.05	2212.8± 1780.3D	0.07
NK	302.9±416.8 C	-0.09	801.9±951.5 F	-0.05	1104.8±1342.9E	-0.06
PK	829.2±279.8 B	0.37	453.7±286.2 F	0.12	1282.9± 430.2E	0.38
NPK	941.0±612.3 B	0.14	2571.4±1580.9D	0.17	3512.5±1985.5C	0.22
NPKM	1569.5±429.1 A	0.48	5185.8±1026.6 B	0.58	6755.2±1034.9 A	0.65
1.5NPKM	1555.6±478.2 A	0.42	5802.2± 1225.1A	0.54	7357.8±1343.6A	0.61
NPKS	1065.9±653.6 B	0.16	2969.6±1802.5 D	0.18	4034.5±2268.0 C	0.23
M	1349.3±424.0 A	0.41	3760.2±1064.1C	0.46	5109.5±1146.0B	0.51

作物 Crop	样本数 N	线线模型LL		线性-平台模型LP		米切里西方程EXP		农学阈值平均 Mean of CV (mg·kg^-1)
作物 Crop	样本数 N	农学阈值 CV (mg·kg^-1)	R²	农学阈值 CV (mg·kg^-1)	R²	农学阈值 CV (mg·kg^-1)	R²	农学阈值平均 Mean of CV (mg·kg^-1)
小麦 Wheat	108	13.5	0.72**	22.3	0.67**	28.8	0.69**	21.5
玉米 Maize	108	23.4	0.66**	29.2	0.65**	46.0	0.67**	32.9