Almost 10 hetares of harvested sites of eucalypt plantation were divided into four equal blocks, and three planting patterns were randomly arranged within each block in July 2016. The first planting pattern (E) was the continuous planting of pure Eucalyptus. urograndis (hybrid strain of Eucalyptus urophylla and Eucalyptus grandis) plantations of the third generation at a density of 1,667 plants/ha. The second planting pattern (EC) was the creation of mixed plantations of E. urograndis and Cinnamomum camphora (mixed pattern: inter-row, mixed density: 1667 plants/ha). The third planting pattern (EH) was the creation of mixed plantations of E. urograndis and Castanopsis hystrix (mixed pattern: inter-row, mixed density: 1667 plants/ha). Simultaneously, four unmanaged first-generation E. urophylla plantations in Luogangling Forest Park were selected as controls (CK). Information on forestland preparation, seedling specifications of eucalypts and native trees, and later plantation tending can be found in Xu et al. (2022) (link).
Sixteen mixed topsoil samples in the 10-cm layer were collected in December 2019 by removing the humus and litterfall from four different planting patterns. Soil samples for fungal community structure analysis were preserved with dry ice in centrifuge tubes and transferred to a-80°C freezer as soon as possible. Other soil samples for analyses of soil chemical properties and enzyme activities were stored in a portable refrigerator at 4°C.
The pH of each sample was determined with an electronic pH meter (soil: water, 1:2.5). Soil OM was determined by the potassium dichromate-sulfate colorimetric method (Sims and Haby, 1971 (link)). Total nitrogen (TN) and total phosphorus (TP) were measured with the Kjeldahl method (Tsiknia et al., 2014 (link)) and sodium hydroxide fusion-molybdenum antimony colorimetric method (Liu H. et al., 2017 (link)), respectively. Nitrate nitrogen (NO¯ 3_N) was determined by 2 mol·L−1 KCl leaching-indophenol blue colorimetric method and ammonium nitrogen (NH+ 4_N) was determined by UV spectrophotometry (Lu, 1999 ). Available phosphorus (AP) was measured by the hydrochloric acid-ammonium fluoride extraction-molybdenum antimony colorimetric method (Lu, 1999 ). Soil available zinc (AZn) and available calcium (ACa) were measured by hydrochloric acid extract, atomic absorption spectrophotometry and ammonium acetate exchange, atomic absorption spectrophotometry, respectively (Liu J. et al., 2017 (link)). For soil enzyme activities, acid phosphatase (ACP) was determined by Phenylphosphonium-4-amino-antipyrine colorimetric method (Guan, 1986 ), urease (URE) by alkaline dish diffusion-HCL titration method (Guan, 1986 ), and invertase (INV) by 3,5-Dinitrosalicylic acid colorimetric method (Lu, 1999 ).
Sixteen mixed topsoil samples in the 10-cm layer were collected in December 2019 by removing the humus and litterfall from four different planting patterns. Soil samples for fungal community structure analysis were preserved with dry ice in centrifuge tubes and transferred to a-80°C freezer as soon as possible. Other soil samples for analyses of soil chemical properties and enzyme activities were stored in a portable refrigerator at 4°C.
The pH of each sample was determined with an electronic pH meter (soil: water, 1:2.5). Soil OM was determined by the potassium dichromate-sulfate colorimetric method (Sims and Haby, 1971 (link)). Total nitrogen (TN) and total phosphorus (TP) were measured with the Kjeldahl method (Tsiknia et al., 2014 (link)) and sodium hydroxide fusion-molybdenum antimony colorimetric method (Liu H. et al., 2017 (link)), respectively. Nitrate nitrogen (NO¯ 3_N) was determined by 2 mol·L−1 KCl leaching-indophenol blue colorimetric method and ammonium nitrogen (NH+ 4_N) was determined by UV spectrophotometry (Lu, 1999 ). Available phosphorus (AP) was measured by the hydrochloric acid-ammonium fluoride extraction-molybdenum antimony colorimetric method (Lu, 1999 ). Soil available zinc (AZn) and available calcium (ACa) were measured by hydrochloric acid extract, atomic absorption spectrophotometry and ammonium acetate exchange, atomic absorption spectrophotometry, respectively (Liu J. et al., 2017 (link)). For soil enzyme activities, acid phosphatase (ACP) was determined by Phenylphosphonium-4-amino-antipyrine colorimetric method (Guan, 1986 ), urease (URE) by alkaline dish diffusion-HCL titration method (Guan, 1986 ), and invertase (INV) by 3,5-Dinitrosalicylic acid colorimetric method (Lu, 1999 ).
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