The establishment and development of Haloxylon ammodendron promotes salt accumulation in surface soil of arid sandy land

doi:10.3724/SP.J.1226.2019.00116.

Abstract

Abstract:

Haloxylon ammodendron, a representative C₄ succulent xerophyte and salt-secreting plant, is widely used in vegetation reestablishment programs to stabilize shifting sand, and is one of the dominant shrubs in the shelter belt used to control desertification in the desert-oasis ecotone in northwestern China. In this study, we collected soil samples in an age sequence of 0-, 2-, 5-, 13-, 16-, 31-, and 39-year-old H. ammodendron plantations to assess the effects of the shrub on soil fertility and salinity. Results show that SOC and total N concentrations increased significantly with increasing plantation age and increased 5.95- (in the interspaces) to 9.05-fold (under the canopy) and 6.15- to 8.46-fold at the 0?5 cm depth at the 39-year-old plantation compared with non-vegetated sandy land. Simultaneously, H. ammodendron establishment and development resulted in significant salt accumulation in the surface layer. On average, total soil salt content at the 0?5 cm and 5?20 cm depth increased 16.8-fold and 4.4-fold, respectively, compared with non-vegetated sandy land. The increase of total salt derived mostly from the accumulation of SO $4 2 -$ , Ca²⁺ and Na⁺ with H. ammodendron development. The accumulation in salinity was more significant than the increase in fertility, suggesting that improved soil fertility did not limit the impact of salinization. The adverse effect of salt accumulation may result in H. ammodendron plantation degradation and impact community stability in the long run.

Key words: Haloxylon ammodendron, soil salt and its component, soil organic carbon, plantation chronosequence, sandy land in desert-oasis ecotone

YongZhong Su,TingNa Liu,JunQia Kong. The establishment and development of Haloxylon ammodendron promotes salt accumulation in surface soil of arid sandy land[J].Sciences in Cold and Arid Regions, 2019, 11(2): 116-125.

Figures/Tables 4

Figure 1

Table 1

Soil salt component and electrical conductivity (EC) in H. ammodendron plantations of different establishment age"

Saltion (cmol/kg)	Depth(cm)	Sampling location	Plantation age								F value	P
Saltion (cmol/kg)	Depth(cm)	Sampling location	0	2	5	9	13	16	31	39	F value	P
SO $4 2 -$	0?5	UC	0.18±0.02 e	0.27±0.02 de	0.47±0.07 de	0.74±0.09 d	0.83±0.03 d	1.79±0.04 c	7.22±0.98 b	14.13±0.38 a	538.4	<0.001
	0?5	OC	0.18±0.03 c	0.20±0.03 c	0.37±0.04 c	0.58±0.06 c	0.58±0.05 c	0.65±0.04 c	6.41±0.12 b	14.51±1.10 a	514.6	<0.001
	5?20	UC	0.44±0.04 d	0.20±0.03 f	0.37±0.07 de	0.46±0.01 de	0.64±0.03 d	0.92±0.11 c	2.18±0.08 b	3.14±0.28 a	159.8	<0.001
	5?20	OC	0.44±0.04 d	0.19±0.03 f	0.33±0.01 de	0.34±0.04 de	0.67±0.05 d	0.99±0.06 c	2.08±0.11 b	2.85±0.35 a	226.9	<0.001
Cl^?	0?5	UC	0.45±0.05 d	0.38±0.05 d	0.69±0.05 c	0.79±0.08 c	0.75±0.12 c	0.80±0.11 c	1.02±0.16 b	1.17±0.20 a	15.6	<0.001
	0?5	OC	0.45±0.05 bc	0.26±0.03 c	0.40±0.05 bc	0.32±0.03 c	0.46±0.05 bc	0.71±0.07 b	1.25±0.04 a	1.56±0.51 a	20.1	<0.001
	5?20	UC	0.23±0.02 d	0.32±0.04 bc	0.39±0.04 c	0.34±0.06 c	0.42±0.07 c	0.27±0.08 b	0.58±0.04 b	0.90±0.13 a	30.8	<0.001
	5?20	OC	0.23±0.02 e	0.29±0.02 de	0.24±0.02 de	0.32±0.06 cd	0.27±0.03 d	0.35±0.06 c	0.93±0.07 a	0.66±0.06 b	81.8	<0.001
HCO $3 -$	0?5	UC	0.35±0.07 e	0.25±0.01 ef	0.49±0.05 de	0.52±0.05 d	1.26±0.10 c	1.51±0.02 b	1.72±0.04 a	1.43±0.20 b	139.0	<0.001
	0?5	OC	0.35±0.07 e	0.36±0.09 e	0.81±0.09 d	0.76±0.08 d	1.68±0.04 a	1.29±0.09 b	1.01±0.08 c	1.14±0.13 c	82.3	<0.001
	5?20	UC	0.44±0.09 c	0.57±0.03 c	0.91±0.14 b	1.06±0.03 ab	1.14±0.31 a	0.93±0.04 b	1.28±0.08 a	1.06±0.11 ab	13.5	<0.001
	5?20	OC	0.44±0.09 d	0.61±0.07 c	0.59±0.02 c	0.96±0.06 c	1.29±0.05 a	1.16±0.09 b	0.48±0.02 cd	1.11±0.13 b	58.9	<0.001
K⁺	0?5	UC	0.05±0.01 b	0.05±0.01 b	0.09±0.01 b	0.07±0.01 b	0.10±0.02 b	0.09±0.01 b	0.66±0.11 a	0.66±0.07 a	100.0	<0.001
	0?5	OC	0.05±0.01 d	0.06±0.01 d	0.15±0.03 c	0.16±0.05 b	0.21±0.05 bc	0.09±0.01 d	0.89±0.07 a	0.79±0.20 a	52.4	<0.001
	5?20	UC	0.07±0.01 e	0.04±0.01 e	0.04±0.01 e	0.11±0.01 d	0.17±0.01 c	0.22±0.03 b	0.22±0.03 b	0.35±0.03 a	71.8	<0.001
	5?20	OC	0.07±0.01 d	0.08±0.01 d	0.08±0.01 d	0.10±0.04 c	0.16±0.01 c	0.10±0.02 d	0.20±0.01 b	0.33±0.02 a	78.4	<0.001
Ca²⁺	0?5	UC	0.49±0.05 cd	0.43±0.04 d	0.62±0.01 cd	0.72±0.11 cd	0.89±0.06 c	0.86±0.08 c	3.20±0.57 b	8.51±0.34 a	407.8	<0.001
	0?5	OC	0.49±0.05 cd	0.44±0.03 d	0.31±0.05 cd	0.54±0.05 cd	0.45±0.03 c	0.65±0.06 c	1.67±0.02 b	8.84±1.17 a	148.1	<0.001
	5?20	UC	0.43±0.01c	0.27±0.04 d	0.45±0.08 c	0.28±0.06 d	0.36±0.03 cd	0.56±0.04 b	0.58±0.03 b	0.89±0.07 a	44.0	<0.001
	5?20	OC	0.43±0.01 c	0.38±0.03 c	0.34±0.05 cd	0.29±0.01d	0.36±0.04 cd	0.45±0.02 c	0.72±0.01 b	1.11±0.15 a	61.9	<0.001
Na⁺	0?5	UC	0.27±0.01 e	0.33±0.03 e	0.64±0.08 e	0.72±0.06 de	1.38±0.14 d	2.69±0.17 c	5.50±1.08 b	6.54±0.35 a	107.5	<0.001
	0?5	OC	0.27±0.01 f	0.35±0.01 f	1.15±0.11 e	1.18±0.14 e	1.84±0.11 c	1.93±0.10 c	4.83±0.03 b	5.48±1.02 a	84.4	<0.001
	5?20	UC	0.38±0.02 ef	0.40±0.02 e	0.77±0.21 de	0.86±0.12 d	1.67±0.12 c	1.11±0.12 d	2.29±0.36 b	3.14±0.42 a	58.0	<0.001
	5?20	OC	0.38±0.02 e	0.57±0.04 d	0.99±0.06 c	1.20±0.09 c	1.24±0.21 c	1.20±1.13 c	1.41±0.26 b	2.96±0.33 a	78.1	<0.001
Mg²⁺	0?5	UC	0.21±0.01 d	0.21±0.02 d	0.23±0.02 d	0.47±0.03 e	0.50±0.04 d	0.62±0.01 c	1.24±0.10 a	0.82±0.11 b	125.4	<0.001
	0?5	OC	0.21±0.01 d	0.15±0.01 d	0.15±0.02 d	0.25±0.02 d	0.22±0.04 d	0.48±0.06 c	1.22±0.01 a	1.04±0.21b	85.5	<0.001
	5?20	UC	0.26±0.04 cd	0.27±0.02 cd	0.20±0.09 cd	0.22±0.08 cd	0.13±0.01 d	0.34±0.09 bc	0.83±0.14 a	0.47±0.13 b	20.0	<0.001
	5?20	OC	0.26±0.04 c	0.25±0.02 c	0.26±0.09 c	0.18±0.02 d	0.21±0.05 cd	0.26±0.06 c	0.61±0.01 b	0.74±0.05 a	100.9	<0.001
Total anions	0?5	UC	0.98±0.06 f	0.91±0.07 f	1.64±0.15 e	2.05±0.07 de	2.83±0.17 d	4.10±0.07 c	9.95±0.83 b	16.72±0.61 a	665.6	<0.001
	0?5	OC	0.98±0.06 d	0.95±0.06 d	1.39±0.13 d	1.65±0.17 d	2.72±0.07 c	2.65±0.17 c	8.67±0.02 b	17.21±1.31 a	438	<0.001
	5?20	UC	1.11±0.11 e	1.07±0.07 e	1.52±0.15 d	1.74±0.12 d	2.22±0.27 c	2.19±0.11 c	3.93±0.04 b	4.81±0.35 a	164.2	<0.001
	5?20	OC	1.11±0.11 f	1.11±0.09 f	1.20±0.08 f	1.74±0.01 e	2.20±0.04 d	2.42±0.10 c	3.27±0.14 b	4.91±0.25 a	347.9	<0.001
Total cations	0?5	UC	1.00±0.04 f	1.02±0.01 f	1.58±0.09 e	1.98±0.11 e	2.87±0.17 d	4.26±0.17 c	10.61±0.64 b	16.53±0.52 a	997.4	<0.001
	0?5	OC	1.00±0.04 e	1.00±0.02 e	1.76±0.11 de	2.30±0.14 cd	2.71±0.10 c	3.15±0.10 c	8.62±0.08 b	16.15±1.45 a	308.1	<0.001
	5?20	UC	1.14±0.06 de	1.03±0.04 e	1.50±0.10 d	1.46±0.04 de	2.32±0.09 c	2.10±0.26 c	3.80±0.09 b	4.84±0.48 a	136.8	<0.001
	5?20	OC	1.14±0.06 f	1.24±0.07 e	1.63±0.07 d	1.78±0.08 d	1.98±0.22 cd	2.13±0.07 c	2.96±0.05 b	5.17±0.18 a	367.2	<0.001
Total salt	0?5	UC	1.98±0.03 f	1.92±0.07 f	3.22±0.24 e	4.03±0.17 e	5.71±0.34 d	8.36±0.23 c	20.56±1.12 b	33.26±1.12 a	1095.9	<0.001
	0?5	OC	1.98±0.03 d	1.95±0.07 d	3.14±0.07 d	3.95±0.11 cd	5.42±0.17 c	5.80±0.25 c	17.30±0.09 b	33.36±2.76 a	373.3	<0.001
	5?20	UC	2.25±0.17 e	2.10±0.03 e	3.02±0.25 d	3.20±0.10 d	4.55±0.30 c	4.30±0.35 c	7.73±0.09 b	9.65±0.58 a	269.9	<0.001
	5?20	OC	2.25±0.17g	2.35±0.16 g	2.84±0.10 f	3.52±0.10 e	4.18±0.26 d	4.55±0.06 c	6.23±0.11 b	10.08±0.43 a	484.5	<0.001
EC	0?5	UC	115±12 c	135±12 c	692±147 bc	973±739 bc	1,001±677 bc	1,146±552 ab	1,589±816 ab	1,996±539 a	4.45	0.006
	0?5	OC	115±12 c	362±100 c	620±137 bcd	650±181 bc	789±393 bc	1,078±450 a	911±458 a	1,456±767 a	3.86	0.012
	5?20	UC	157±42 cd	164±48 c	137±15 c	481±120 b	615±166 b	384±138 bc	625±357 b	968±136 a	10.14	<0.001
	5?20	OC	157±42 cd	371±111 c	142±27 d	404±57 cd	881±26 b	416±255 c	709±127 b	1,328±153 a	31.42	<0.001

Table 1

Table 2

Figure 2

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Soil properties	Depth (cm)	Plantation age							F value	P
Soil properties	Depth (cm)	2	5	9	13	16	31	39	F value	P
SOC	0?5	1.05±0.02 c	1.89±0.01 a	1.52±0.42 abc	1.41±0.12 abc	1.53±0.33 abc	1.21±0.18 bc	1.70±0.55 ab	2.67	0.019
SOC	5?20	1.03±0.14 d	1.44±0.07 bc	1.12±0.15 cd	1.00±0.03 d	1.69±0.38 ab	1.32±0.25 c	1.80±0.18 a	7.42	0.001
Total N	0?5	1.14±0.14 cd	2.42±0.11 a	1.72±0.40 bc	1.37±0.17 cd	1.89±0.23 b	1.22±0.06 d	1.39±0.05 cd	15.35	<0.001
Total N	5?20	1.04±0.11 c	1.63±0.18 ab	1.15±0.14 c	1.36±0.37 b	1.46±0.36 ab	1.84±0.28 a	1.28±0.13 bc	3.77	0.019
Total anions	0?5	1.14±0.27 bc	1.09±0.20 bc	1.24±0.10 b	1.04±0.06 bc	1.55±0.12 a	1.15±0.10 bc	0.97±0.07 c	4.80	0.007
Total anions	5?20	0.97±0.07 b	1.27±0.06 a	1.00±0.07 b	1.01±0.12 b	0.90±0.0.07 b	1.20±0.06 a	0.98±0.11 b	8.04	0.001
Total cations	0?5	1.01±0.03 cd	0.90±0.04 d	0.86±0.01d	1.06±0.08 c	1.35±0.09 a	1.23±0.08 b	1.03±0.10 c	20.0	<0.001
Total cations	5?20	0.83±0.06 b	0.92±0.09 b	0.82±0.06 b	1.18±0.10 a	0.99±0.14 b	1.32±0.16 a	0.93±0.07 b	9.25	<0.001
Total salt	0?5	1.07±0.12 bc	0.98±0.08 c	1.02±0.03 c	1.05±0.07 d	1.44±0.10 a	1.19±0.07 b	1.00±0.08 c	11.2	<0.001
Total salt	5?20	0.89±0.06 c	1.06±0.08 b	0.91±0.03 c	1.08±0.03 b	0.95±0.09 c	1.26±0.10 a	0.96±0.50 c	11.5	<0.001

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