The study analyzed the soil chemical properties, nutrient contents and distribution characteristics in the litchi gardens from the major growing regions in Yunnan aimed to provide supports for nutrient and fertilization management in litchi gardens. Soil samples were collected from 22 litchi gardens in 6 major production regions. Soil pH, organic matter and multi-elements content were analyzed and used as the indicators to evaluate soil fertility via fuzzy comprehensive analysis. The results showed that soil pH was 5.62, with 22.73% of soil samples were suitable for litchi growth (pH=5.0~5.5). The cation exchange capacity (CEC) of 27.28% of soils was lower than 10.00 cmol/kg, indicating fertilizer retention ability should be improved. Organic matter content was relatively high (14.81-57.06 g/kg). Soil total N content (0.84-2.70 g/kg) was higher than medium level (>1.00 g/kg) excepting for Baoshan region. Soil alkaline hydrolyzed N (78.61-259.19 mg/kg), available P (21.14-92.48 mg/kg) and available K (35.00-642.50 mg/kg) were all higher than medium level excepting one orchard in Yongde, where the available K content (36.67 mg/kg) was at deficiency level (<50.00 mg/kg). Among the trace elements, available Ca (415.63-4900.00 mg/kg) and available S (20.43-127.89 mg/kg) were relatively abundant. Soil available Mg (3.13-512.50 mg/kg) was at moderate level, with 42.43% of samples were below the limit value (<100.00 mg/kg). Available Zn (0.51-9.68 mg/kg) and available Fe (7.18-124.82 mg/kg) were abundant. Available Mn (2.56-104.78 mg/kg) and available Cu (0.76-6.06 mg/kg) were at moderate level, with 8.60% of the samples showing available Mn lowering than 5.00 mg/kg. Available B and Mo were at sufficient level in Yingjiang at 0.88 and 0.43 mg/kg, while those in Pingbian (B: 0.44 mg/kg, Mo: 0.13 mg/kg), Yuanyang (B: 0.31 mg/kg, Mo: 0.15 mg/kg), Baoshan (Mo: 0.10 mg/kg), Yongde (B: 0.42 mg/kg, Mo: 0.10 mg/kg) and Xinping (B: 0.41 mg/kg, Mo: 0.10 mg/kg) were at deficient levels. The integrated fertility index (IFI) was 0.51-0.97, with average value at 0.79. All IFI values were above level II excepting Baoshan region at level III. The principal component analysis showed that total N, alkaline hydrolyzed N, organic matter and pH were the most important factors affecting soil fertility. The data suggested that the overall soil fertility of the studied 22 litchi gardens was above the medium level. Mg and Mo fertilizers can be improved in Baoshan, and B and Mo fertilizers can be improved in Pingbian, Yuanyang, Yongde and Xinping.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |