Table 1.
Locations, physicochemical properties, and planted fruit trees of the soil samples.
| Soil samples | Locations | Physicochemical properties* | Planted fruit tree | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Type | Code | Latitude | Longitude | Altitude/m | County, province | pH | TP/g kg−1 DW | WSP/mg kg−1 DW | Species | Tree age/years |
| Karst | KGY1 | 28°01′25″N | 108°29′07″E | 517 | Yinjiang, Guizhou | 8.40 ± 0.01 A | 0.58 ± 0.01 B | 0.69 ± 0.20 D | Citrus maxima (Burm) Merr. | 10 |
| KHT1 | 28°27′40″N | 109°29″52″E | 550 | Huayuan, Hunan | 6.84 ± 0.07 C | 0.60 ± 0.05 B | 0.20 ± 0.03D | Amygdalus persica L. | 3 | |
| KHZ1 | 28°26′33″N | 109°28′49″E | 550 | Huayuan, Hunan | 7.94 ± 0.02 B | 0.31 ± 0.03 CD | 0.20 ± 0.03 D | Ziziphus jujuba Mill. | 3 | |
| KNY2 | 28°12′38″N | 112°35′42″E | 388 | Ningwu, Hunan | 5.35 ± 0.10 F | 0.29 ± 0.01 D | 1.37 ± 0.39 C | Citrus aurantium L. | 10 | |
| KXB1 | 26°32′08″N | 110°45′41″E | 365 | Xinning, Hunan | 6.20 ± 0.06 D | 0.37 ± 0.03 CD | 0.29 ± 0.05 D | Castanea mollissima BL. | 5 | |
| Non-karst | KXQ2 | 26°31′46″N | 110°45′03″E | 353 | Xinning, Hunan | 5.70 ± 0.16 E | 0.55 ± 0.04 B | 0.91 ± 0.19 CD | Citrus sinensis L. Osbeck | 10 |
| NCX2 | 43°54′13″N | 125°20′37″E | 211 | Changchun, Jilin | 8.38 ± 0.14 A | 0.71 ± 0.02 A | 6.89 ± 0.21 A | Armeniaca vulgaris Lam. | 20 | |
| NCX3 | 43°49′13″N | 125°16′41″E | 251 | Changchun, Jilin | 8.27 ± 0.04 A | 0.38 ± 0.03 C | 4.71 ± 0.42B | Armeniaca vulgaris Lam. | 10 | |
WSP, the water-soluble phosphorus content; TP, the total phosphorus content. *, the data comparison experiments were performed in triplicate. Values are shown as means ± SD. Different capital letters indicate significant differences based on the S-N-K method of one-way ANOVA at P < 0.01 with IBM SPSS Statistics 22.0 (SPSS Inc., Chicago, IL, USA).