Ecological stoichiometry of soil carbon, nitrogen and phosphorus in farmland salinization in arid oasis

doi:10.6048/j.issn.1001-4330.2023.08.021

Abstract

Abstract:

【Objective】 The aim of the study is to reveal soil C, N and P stoichiometry of agricultural salinization ecosystem in arid oasis in northern China, which may be helpful for effective rehabilitation of salinized desertification.【Methods】 By using the method of replacing time with space, the soil stoichiometry (0~40 cm) in alfalfa and barley growing fields in different salinized stages, including the native (CK), lightly, moderately, heavily, severely salinized field was studied.【Results】 (1) In alfalfa grown field, soil organic C (SOC), total N concentrations (TN) increased firstly and then decreased with an increase in salinity, while total phosphorus concentration (TP) decreased.SOC, TN, and TP concentrations decreased in barley growing field.It was found that SOC, TN, and TP concentrations in two farmlands accumulated in the surface of soil layers among the five stages.(2) With an increase in salinity, C/N in alfalfa growing field presented a “V” change trend and the moderately salinized field C/N was the lowest, but C/P and N/P increased firstly and then decreased.The C/N increased in barley growing field, but C/P and N/P decreased.Analysis showed that C/N in the depth of 0-10 cm, 10-20 cm and 20-40 cm was not significantly different in alfalfa growing field among different salinized stages.In the two farmlands, C/N, C/P and N/P was not significantly different among different soil depths in each salinized stage.(3) Analysis showed that TN, TP, C/P and N/P had significant positive correlation with SOC in two farmlands.A significant negative correlation was found between TN, and C/N (P<0.05), but C/P and N/P had very significant positive correlation with TN (P<0.01).And C/N had very significant negative correlation with N/P, but a very significant positive correlation was found between C/P and N/P (P<0.01).C/N, C/P, N/P had no significant correlation with TP in two farmlands.(4) Analysis showed that soil water content, soil EC_P, fine particle content had significant correlation with the soil stoichiometry at alfalfa growing field (P<0.05).The soil stoichiometry had significant correlation with soil water content, soil EC_P,soil bulk density and soil temperature at barley growing field.【Conclusion】 Soil SOC and TN are major factors which affect soil stoichiometry, but TP is not the factor.

Key words: oasis; farmland salinization; soil carbon nitrogen and phosphorus; soil stoichiometric characteristics

摘要：

【目的】研究荒漠绿洲农田盐渍化生态系统土壤C、N、P含量生态化学计量学特征,为盐渍化治理提供参考。【方法】以空间代替时间的方法,选取干旱绿洲区紫花苜蓿和大麦2种作物不同盐渍化农田为对象,以未盐渍化农田为对照,研究农田盐渍化过程中土壤(0~40 cm)C、N、P生态化学计量特征。【结果】(1)在0~40 cm土层,随盐渍化程度的加剧,紫花苜蓿地土壤SOC和TN含量表现为先增后减的变化,全磷(TP)含量表现为波动式降低;大麦地土壤SOC、TN和TP含量表现为波动式降低的变化。2种作物地,不同盐渍化阶段农田土壤养分含量垂直分布上表现出明显的“表聚性”特征。(2)在农田盐渍化过程中,随盐渍化的加剧,在紫花苜蓿地,C/N呈“V”型变化;在中度盐渍化阶段C/N比值最低;C/P和N/P值表现为先增后减的变化趋势,在中度盐渍化阶段C/P和N/P值比值最高;在大麦地,C/N值表现为波动式增加,C/P值和N/P值表现为降低趋势。在紫花苜蓿地,0~10、10~20、20~40 cm土层土壤C/N在不同盐渍化阶段间无显著性差异;2种作物地,在各盐渍化阶段土壤C/N、C/P及N/P在不同土层间也无显著性差异。(3)2种作物地,土壤SOC与土壤TN、土壤TP、C/P、N/P有显著的正相关关系;TN与C/N呈显著负相关关系(P<0.05),与C/P、N/P呈极显著正相关关系(P<0.01);土壤C/N与N/P有极显著负相关关系,C/P与N/P有极显著正相关关系(P<0.01)。在2种作物地,TP与C/N、C/P、N/P没有显著相关性。(4)土壤养分化学计量特征,在紫花苜蓿地,与土壤含水量、土壤电导率和土壤黏粉粒含量有显著相关关系(P<0.05);在大麦地,与土壤含水量、土壤电导率、土壤容重和土壤温度有显著相关关系。【结论】在农田盐渍化过程中土壤SOC与TN是影响土壤养分生态化学计量比的主要因素,TP不是土壤养分限制的主要因素。

关键词: 荒漠绿洲, 农田盐渍化过程, 土壤碳氮磷, 生态化学计量学

CLC Number:

S156.4

WANG Yan, WU Xingbao, QIN Xinhui, ZHANG Yongjiu, YANG Li, ZHAO Halin. Ecological stoichiometry of soil carbon, nitrogen and phosphorus in farmland salinization in arid oasis[J]. Xinjiang Agricultural Sciences, 2023, 60(8): 1996-2005.

王燕, 武兴宝, 秦新惠, 张永久, 杨丽, 赵哈林. 荒漠绿洲农田盐渍化过程中的土壤碳、氮、磷生态化学计量特征[J]. 新疆农业科学, 2023, 60(8): 1996-2005.

Figures/Tables 5

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作物 Crop	不同盐渍化农田 Different salinized stages	有机碳 Soil organic carbon (g/kg)	全氮 Total nitrogen (g/kg)	全磷 Total phosphorus (g/kg)	C/N	C/P	N/P
大麦 Barley	CK	7.82±1.40^A	0.86±0.19^A	1.37±0.12^AB	9.33±0.35^B	5.74±1.06^A	0.63±0.15^A
	S₁	8.18±0.76^A	0.87±0.10^A	1.49±0.14^A	9.50±0.73^B	5.55±0.64^A	0.59±0.11^AB
	S₂	6.36±0.63^B	0.65±0.07^B	1.30±0.01^B	9.78±0.19^AB	4.91±0.48^AB	0.50±0.05^AB
	S₃	5.04±0.25^BC	0.57±0.06^BC	1.27±0.05^B	8.98±0.51^B	4.00±0.33^BC	0.45±0.06^BC
	S₄	4.22±0.36^C	0.40±0.04^C	1.30±0.04^B	10.50±0.33^A	3.23±0.24^C	0.31±0.02^C
苜蓿 Alfalfa	CK	5.33±0.39^ABC	0.52±0.06^AB	1.61±0.17^A	10.31±0.31^A	3.32±0.10^B	0.32±0.00^BC
	S₁	6.30±0.73^A	0.62±0.08^A	1.66±0.06^A	10.25±0.93^A	3.79±0.44^AB	0.37±0.04^B
	S₂	5.83±0.25^AB	0.63±0.05^A	1.38±0.11^B	9.25±0.35^B	4.24±0.25^A	0.46±0.03^A
	S₃	4.76±1.04^BC	0.47±0.10^B	1.39±0.10^B	10.09±0.44^AB	3.40±0.53^B	0.34±0.05^BC
	S₄	4.22±0.36^C	0.40±0.04^B	1.30±0.04^B	10.50±0.33^A	3.23±0.24^B	0.31±0.02^C

作物 Crop	不同盐渍化农田 Different salinized stages	有机碳 Soil organic carbon (g/kg)	全氮 Total nitrogen (g/kg)	全磷 Total phosphorus (g/kg)	C/N	C/P	N/P
大麦 Barley	CK	7.82±1.40^A	0.86±0.19^A	1.37±0.12^AB	9.33±0.35^B	5.74±1.06^A	0.63±0.15^A
	S₁	8.18±0.76^A	0.87±0.10^A	1.49±0.14^A	9.50±0.73^B	5.55±0.64^A	0.59±0.11^AB
	S₂	6.36±0.63^B	0.65±0.07^B	1.30±0.01^B	9.78±0.19^AB	4.91±0.48^AB	0.50±0.05^AB
	S₃	5.04±0.25^BC	0.57±0.06^BC	1.27±0.05^B	8.98±0.51^B	4.00±0.33^BC	0.45±0.06^BC
	S₄	4.22±0.36^C	0.40±0.04^C	1.30±0.04^B	10.50±0.33^A	3.23±0.24^C	0.31±0.02^C
苜蓿 Alfalfa	CK	5.33±0.39^ABC	0.52±0.06^AB	1.61±0.17^A	10.31±0.31^A	3.32±0.10^B	0.32±0.00^BC
	S₁	6.30±0.73^A	0.62±0.08^A	1.66±0.06^A	10.25±0.93^A	3.79±0.44^AB	0.37±0.04^B
	S₂	5.83±0.25^AB	0.63±0.05^A	1.38±0.11^B	9.25±0.35^B	4.24±0.25^A	0.46±0.03^A
	S₃	4.76±1.04^BC	0.47±0.10^B	1.39±0.10^B	10.09±0.44^AB	3.40±0.53^B	0.34±0.05^BC
	S₄	4.22±0.36^C	0.40±0.04^B	1.30±0.04^B	10.50±0.33^A	3.23±0.24^B	0.31±0.02^C

作物 Crop	土层 Soil layer (cm)	盐渍化阶段 Salinized stage	C/N	C/P	N/P
苜蓿 Alfalfa	0~10	CK	10.38±0.25^Aa	3.56±0.44^Aa	0.34±0.05^ABa
		S₁	10.64±0.31^Aa	3.81±0.42^Aa	0.36±0.03^ABa
		S₂	9.23±1.23^Aa	4.22±0.86^Aa	0.47±0.13^Aa
		S₃	9.90±1.18^Aa	3.60±0.56^Aa	0.37±0.08^ABa
		S₄	10.36±0.92^Aa	3.36±0.26^Aa	0.33±0.03^Ba
	10~20	CK	10.35±0.86^Aa	3.50±0.33^ABa	0.34±0.01^ABa
		S₁	10.48±0.56^Aa	3.84±0.52^ABa	0.37±0.03^ABa
		S₂	10.02±1.67^Aa	4.22±0.12^Aa	0.43±0.09^Aa
		S₃	10.68±0.25^Aa	3.38±0.80^ABa	0.32±0.07^Ba
		S₄	10.74±0.59^Aa	3.27±0.35^Ba	0.30±0.02^Ba
	20~40	CK	10.13±0.37^Aa	2.81±0.70^BCa	0.28±0.08^Ba
		S₁	9.76±1.82^Aa	3.67±0.75^ABCa	0.39±0.14^ABa
		S₂	8.98±1.57^Aa	4.40±0.60^Aa	0.50±0.12^Aa
		S₃	9.85±0.35^Aa	3.15±0.21^Ca	0.32±0.02^Ba
		S₄	10.46±0.14^Aa	3.06±0.17^Ca	0.29±0.02^Ba
大麦 Barley	0~10	CK	8.74±0.93^Ba	6.37±1.69^Aa	0.74±0.27^Aa
		S₁	9.28±0.80^ABa	5.17±1.90^ABa	0.57±0.27^ABa
		S₂	9.79±0.08^ABa	5.29±0.46^ABa	0.54±0.05^ABa
		S₃	9.33±0.29^ABa	3.99±0.33^Ba	0.43±0.04^ABa
		S₄	10.36±0.92^Aa	3.36±0.26^Ba	0.33±0.03^Ba
	10~20	CK	9.72±0.18^ABa	4.32±0.56^ABa	0.45±0.07^ABa
		S₁	9.98±0.36^ABa	5.94±1.87^ABa	0.60±0.20^Aa
		S₂	9.65±0.50^ABa	4.89±0.39^Aa	0.51±0.03^Aa
		S₃	8.89±1.19^Ba	3.70±0.16^Ba	0.42±0.08^ABa
		S₄	10.74±0.59^Aa	3.27±0.35^Ba	0.30±0.02^Ba
	20~40	CK	9.55±0.18^ABCa	6.54±2.06^Aa	0.69±0.23^Aa
		S₁	9.24±1.35^BCa	5.54±1.77^Aa	0.61±0.22^Aa
		S₂	9.91±0.12^ABa	4.55±1.11^ABa	0.46±0.12^ABa
		S₃	8.71±0.49^Ca	4.31±0.83^ABa	0.50±0.12^ABa
		S₄	10.46±0.14^Aa	3.06±0.17^Ba	0.29±0.02^Ba

作物 Crop	土层 Soil layer (cm)	盐渍化阶段 Salinized stage	C/N	C/P	N/P
苜蓿 Alfalfa	0~10	CK	10.38±0.25^Aa	3.56±0.44^Aa	0.34±0.05^ABa
		S₁	10.64±0.31^Aa	3.81±0.42^Aa	0.36±0.03^ABa
		S₂	9.23±1.23^Aa	4.22±0.86^Aa	0.47±0.13^Aa
		S₃	9.90±1.18^Aa	3.60±0.56^Aa	0.37±0.08^ABa
		S₄	10.36±0.92^Aa	3.36±0.26^Aa	0.33±0.03^Ba
	10~20	CK	10.35±0.86^Aa	3.50±0.33^ABa	0.34±0.01^ABa
		S₁	10.48±0.56^Aa	3.84±0.52^ABa	0.37±0.03^ABa
		S₂	10.02±1.67^Aa	4.22±0.12^Aa	0.43±0.09^Aa
		S₃	10.68±0.25^Aa	3.38±0.80^ABa	0.32±0.07^Ba
		S₄	10.74±0.59^Aa	3.27±0.35^Ba	0.30±0.02^Ba
	20~40	CK	10.13±0.37^Aa	2.81±0.70^BCa	0.28±0.08^Ba
		S₁	9.76±1.82^Aa	3.67±0.75^ABCa	0.39±0.14^ABa
		S₂	8.98±1.57^Aa	4.40±0.60^Aa	0.50±0.12^Aa
		S₃	9.85±0.35^Aa	3.15±0.21^Ca	0.32±0.02^Ba
		S₄	10.46±0.14^Aa	3.06±0.17^Ca	0.29±0.02^Ba
大麦 Barley	0~10	CK	8.74±0.93^Ba	6.37±1.69^Aa	0.74±0.27^Aa
		S₁	9.28±0.80^ABa	5.17±1.90^ABa	0.57±0.27^ABa
		S₂	9.79±0.08^ABa	5.29±0.46^ABa	0.54±0.05^ABa
		S₃	9.33±0.29^ABa	3.99±0.33^Ba	0.43±0.04^ABa
		S₄	10.36±0.92^Aa	3.36±0.26^Ba	0.33±0.03^Ba
	10~20	CK	9.72±0.18^ABa	4.32±0.56^ABa	0.45±0.07^ABa
		S₁	9.98±0.36^ABa	5.94±1.87^ABa	0.60±0.20^Aa
		S₂	9.65±0.50^ABa	4.89±0.39^Aa	0.51±0.03^Aa
		S₃	8.89±1.19^Ba	3.70±0.16^Ba	0.42±0.08^ABa
		S₄	10.74±0.59^Aa	3.27±0.35^Ba	0.30±0.02^Ba
	20~40	CK	9.55±0.18^ABCa	6.54±2.06^Aa	0.69±0.23^Aa
		S₁	9.24±1.35^BCa	5.54±1.77^Aa	0.61±0.22^Aa
		S₂	9.91±0.12^ABa	4.55±1.11^ABa	0.46±0.12^ABa
		S₃	8.71±0.49^Ca	4.31±0.83^ABa	0.50±0.12^ABa
		S₄	10.46±0.14^Aa	3.06±0.17^Ba	0.29±0.02^Ba

作物 Crop	项目 Index	TN	TP	C/N	C/P	N/P
苜蓿 Alfalfa	SOC	0.939^**	0.675^**	-0.256	0.763^**	0.682^**
	TN		0.575^*	-0.569^*	0.783^**	0.824^**
	TP			0.001	0.045	0.017
	C/N				-0.388	-0.696^**
	C/P					0.930^**
大麦 Barley	SOC	0.977^**	0.590^*	-0.405	0.951^**	0.898^**
	TN		0.468	-0.573^*	0.971^**	0.961^**
	TP			0.153	0.317	0.212
	C/N				-0.534^*	-0.683^**
	C/P					0.979^**