Data sets on soil bacteria, enzyme activities, physical and chemical properties for different land use types and soil depths

The data contain three types of core indicators:
(1) Soil physicochemical properties: including pH, bulk density (BD), soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), quick-acting phosphorus (AP), and quick-acting potassium (AK) were measured by potentiometric, ferrocyclic, and oxidative potassium dichromate methods, respectively;
(2) Enzyme activity data: six enzymes related to C/N/P cycling (α-glucosidase AG, β-glucosidase BG, etc.) were measured using microplate fluorescence; (3) Microbial community data: 16S rRNA genes VG, β-glucosidase BG, etc., were measured by Illumina PE300 platform. glucosidase AG, β-glucosidase BG, etc.), which were detected using the microtiter plate fluorescence method;
(3) Bacterial community data: bacterial community composition and diversity data (e.g., relative abundance of phyla such as Chloroflexi, Actinobacteriota, etc.) were obtained by sequencing the V4-V5 region of the 16S rRNA gene via the Illumina PE300 platform.
The data collected were systematically analyzed through the above methodology to achieve the following objectives: (i) to study the effects of land use and soil depth on bacterial community composition and enzyme activities; (ii) to elucidate the relationship between soil physicochemical properties and bacterial communities as well as enzyme activities; and (iii) to explore the functional roles of enzymes in nutrient cycling and to predict bacterial functional profiles.
Redundancy and beta diversity analyses revealed that while the dominant bacterial phyla (Chloroflexi, Actinobacteriota, Acidobacteriota, and Proteobacteria) were consistent across land-use types, their relative abundances varied significantly. Cultivated lands exhibited higher bacterial diversity and species richness, along with enhanced functionality in C and N cycling. However, long-term tillage led to a decline in soil organic carbon (SOC), nutrient levels, and associated enzyme activities. Soil physicochemical properties, particularly total nitrogen (TN), SOC, and available phosphorus (AP), were identified as key drivers of bacterial community composition.