Skip to main content
NCBI home page
iScience logoLink to iScience
. 2026 Jan 8;29(2):114650. doi: 10.1016/j.isci.2026.114650

Flooding effects on soil properties, heavy metals, and microbial communities in tea plantations

Caijin Ling 1, Dongxia Liang 1, Liyang Gao 1, Qiaoyi Zhou 1, Hualin Huang 1,2,∗
PMCID: PMC12860698  PMID: 41630902

Summary

The flooding of tea plantation caused by natural rainfall is a common natural disaster, which has adverse effects on the soil quality of tea plantation, the growth of tea trees, and the yield and quality of tea. This article systematically studied the multidimensional effects of natural rainfall (flood conditions) on tea plantation soil for the first time. In this study, the physicochemical properties, heavy metals, and microbial communities of tea plantation soil samples were analyzed at six time points after natural rainfall (flood conditions) at 0, 15, 18, 21, 24, and 27 days. The results showed that natural rainfall (flood conditions) had a significant impact on soil nutrients and heavy metal concentrations in tea plantations. With the extension of flooding time, compared with the pre-flooding control (0 days), soil pH, organic matter, available potassium, available phosphorus, alkali-hydrolyzable nitrogen, and the concentrations of eight heavy metals first increased and then decreased with prolonged flooding, and the concentrations of all heavy metals were lower than the limits of soil environmental quality standards. After flooding, Proteobacteria was the dominant group of bacterial community, and Acidobacterita, Chloroflexi, and Actinobacteriota were also abundant. The fungal community is dominated by Ascomycota and Basidiomycota. Soil components were significantly correlated with microbial community, in which organic matter, available potassium, and pH value had the greatest impact on bacterial community, while fungal community was mainly affected by available potassium, organic matter, Cr, and As. In general, natural rainfall (flood conditions) will reduce the content of nutrients and heavy metals in tea plantation soil and change the soil microbial community structure, which provides a scientific basis for evaluating the impact of natural rainfall on tea plantation soil health.

Subject areas: Applied sciences, Environmental science, Soil science

Graphical abstract

graphic file with name fx1.jpg

Open in a new tab

Highlights

  • •

    First systematic study on multi-dimensional impacts of flooding on tea soil

  • •

    Flooding alters soil composition and reshapes microbial community structure

  • •

    Bacterial communities are mainly driven by soil organic matter, available potassium, and pH

  • •

    Available potassium, organic matter, Cr, and As are key drivers of fungal community structure

Applied sciences; Environmental science; Soil science

Introduction

Tea (Camellia sinensis L.) is an important economic crop in China. After thousands of years of domestication and cultivation, a unique growth habit of liking slightly acidic soil has been formed; especially in slightly acidic soil with a pH value of 4.5–5.5, tea trees exhibit the best growth conditions. In recent years, as the level of tea plantation production intensification increases, tea plantation ecosystems have gradually become homogeneous and less capable of regulation, and the degradation of soils has become increasingly prominent.1,2

Flooding is a common natural phenomenon with significant impacts on agricultural systems, especially sensitive ecosystems such as tea plantations. Tea, as a high-value crop, is highly susceptible to environmental stresses, of which soil health is a key determinant of plant growth and quality.3,4 Excessive waterlogging can disrupt the delicate balance of physical, chemical, and biological properties of soil, leading to reduced nutrient availability, increased accumulation of heavy metals, and changes in soil microbial communities. These changes not only affect plant growth but also threaten the long-term sustainability of tea plantation soils.5,6 Therefore, understanding the effects of inundation on tea plantation soils is essential for developing effective management strategies to mitigate the negative impacts of such environmental stresses.

Tea plantations are widely distributed across subtropical and tropical mountainous regions of southern China—such as Fujian, Yunnan, Guangdong, Zhejiang, and Guizhou—where the East-Asian monsoon climate delivers abundant but highly uneven seasonal rainfall. These characteristics make tea plantations especially vulnerable to short-duration flooding during the early-summer rainy season. Prolonged flooding in tea plantation can lead to hypoxic conditions, which in turn affects soil nutrient cycling, altering key soil components such as organic matter (OM), alkaline-hydrolyzable nitrogen (AN), available phosphorus (AP), and available potassium (AK), and the accumulation of hazardous heavy metals including copper (Cu), lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), mercury (Hg), zinc (Zn), and nickel (Ni).7,8,9 These changes in soil nutrient dynamics may lead to nutrient deficiencies or toxicity, which directly affects the quality and yield of tea plants.10

In addition, soil microbial communities play an important role in maintaining soil health and are involved in nutrient cycling, OM decomposition, and degradation of pollutants.11,12 Flooding may lead to significant changes in microbial community structure, and certain microbial groups may flourish or decline under waterlogged conditions.13,14,15 These microbial changes can further affect nutrient availability, soil fertility, and the overall resilience of tea plantation ecosystems.

Several studies have reported that flooding can lead to changes in soil OM content, nutrient availability, and microbial community structure in other plant systems.10,16,17 However, relatively few studies have been conducted to specifically investigate the effects of flooding on tea plantation soils, especially the effects of different flood durations on soil fertility, heavy metal accumulation, and microbial communities. Given the economic importance of tea production and the high frequency of flood events, understanding these effects is crucial for developing effective flood management strategies for tea plantations.

The purpose of this study was to explore the effects of natural rainfall (flood conditions) on tea plantation, specifically (1) how different flooding durations affect the soil’s physical and chemical properties and heavy metal content, (2) the changes of the abundance and community structure of bacteria and fungi in tea plantation soil under different flooding time, and (3) the key environmental factors and important microbial groups that affect the changes of microbial community structure in tea plantation soil under different flooding time. The results provide a scientific basis for evaluating the effects of natural rainfall on the health of tea plantation soil.

Results

Soil physical and chemical properties

The experimental design is shown in (Figure 1). The physical and chemical properties of the soil before the experiment are shown in (Tables 1 and 2). After different flooding duration treatments, significant changes in the chemical properties of the tea plantation soil were observed, with the most pronounced alterations observed in available nutrient contents (Table 3). Compared to day 0 of flooding, the maximum increases in AN, AP, and AK in the tea plantation soil after different flooding durations were 57.55%, 923.41%, and 110.63%, respectively. However, the increases tended to decrease with prolonged flooding durations, a trend also observed for soil pH and OM content. Additionally, after 21 days of flooding, the pH value of the tea plantation soil increased significantly to 4.73 ± 0.01, remaining acidic, which indicated that short-term flooding treatments may not effectively alleviate soil acidification in tea plantation soils.

Figure 1.

Figure 1

Open in a new tab

Schematic diagram of community layout

In the figure, “CK” represents the control group (flooded for 0 days), and T1, T2, T3, T4, and T5, respectively, represent the treatments of being flooded for 15, 18, 21, 24, and 27 days. Each treatment was set up with three replicates.

Table 1.

Basic soil chemical properties (mg·kg−1)

Index pH OM/g·kg−1 AP AK AN Cu Pb Cd Cr As Hg Zn Ni
Pilot site 5.23 34.04 69.91 172.81 150.19 36.64 35.89 0.12 132.02 31.26 0.05 66.18 23.68
Open in a new tab

Table 2.

Screening values for soil pollution risk in non-paddy agricultural land with pH ≤ 5

Index Cu Pb Cd Cr As Hg Zn Ni
Pilot site 50 70 0.30 150 40 13 200 60
Open in a new tab

Table 3.

Effects of flooding duration on tea plantation soil chemical properties (mg·kg−1)

Index Flooding time/d
0 15 18 21 24 27
pH 4.44 ± 0.01d 4.55 ± 0.01b 4.47 ± 0.01c 4.73 ± 0.01a 4.55 ± 0.01b 4.29 ± 0.01e
Organic matter/g·kg−1 38.30 ± 0.03c 40.32 ± 0.07b 50.74 ± 0.09a 29.82 ± 0.07e 31.89 ± 0.02d 20.95 ± 0.03f
Alkaline nitrogen 140.11 ± 1.16c 165.65 ± 0.67b 220.75 ± 1.17a 118.61 ± 0.89e 126.00 ± 0.58d 89.71 ± 0.58f
Available phosphorus 13.07 ± 0.11e 88.39 ± 0.43b 133.66 ± 0.43a 11.14 ± 0.05f 41.98 ± 0.11c 38.47 ± 0.14d
Available potassium 97.89 ± 0.06e 156.83 ± 0.59c 206.18 ± 0.44b 227.15 ± 1.62a 113.65 ± 0.22d 90.72 ± 0.21f
Open in a new tab

Note: the data in the table represent the average ±SEM of three replicate treatments. Different lowercase letters indicate significant differences during different flooding duration treatment (p < 0.05).

Heavy metals in tea plantation soil

After flooding treatment, the soil Cu, Pb, Cd, Hg, Zn, and Ni contents in the tea plantation soils did not exceed the risk screening values for non-paddy agricultural land with pH ≤ 5.5 (Table 4). However, compared to day 0 of flooding, total Cr content in the soil was 164.67 ± 0.52 mg kg−1 after 18 days of flooding treatment (m[Cr] ≤ 150 mg kg−1, indicating slight Cr contamination), and total As content was 40.76 ± 0.36 mg kg−1 after 18 days and 40.59 ± 0.36 mg kg−1 after 21 days of flooding treatment (m[As] ≤ 40 mg kg−1, indicating slight As contamination at both periods). In addition, by analyzing the correlation between heavy metals and nutrients (Figure S1), we further clarified their impact on relationship.

Table 4.

Effects of different durations on heavy metals concentrations in tea plantation soil (mg·kg−1)

Index Flooding time/d
0 15 18 21 24 27
Cu 34.57 ± 0.10c 37.35 ± 0.11b 33.38 ± 0.05days 38.73 ± 0.033a 30.09 ± 0.22e 30.01 ± 0.05e
Pb 30.66 ± 0.13c 32.85 ± 0.04b 29.47 ± 0.05d 34.30 ± 0.27a 25.67 ± 0.07e 24.38 ± 0.15f
Cd 0.09 ± 0.01b 0.09 ± 0.01b 0.10 ± 0.01a 0.09 ± 0.01b 0.08 ± 0.01c 0.08 ± 0.01c
Cr 126.24 ± 1.68c 140.30 ± 2.41b 164.67 ± 0.52a 143.90 ± 1.56b 117.05 ± 0.29d 122.98 ± 2.24c
As 32.83 ± 0.06c 35.15 ± 0.45b 40.76 ± 0.36a 40.59 ± 0.36a 28.37 ± 0.27d 32.05 ± 0.55c
Hg 0.06 ± 0.01b 0.05 ± 0.01bc 0.08 ± 0.01a 0.05 ± 0.01cd 0.04 ± 0.01d 0.05 ± 0.01bc
Zn 70.10 ± 0.22c 75.23 ± 0.12b 68.92 ± 0.45d 83.70 ± 0.19a 66.85 ± 0.06e 65.60 ± 0.71f
Ni 23.37 ± 0.11b 24.39 ± 0.20a 23.47 ± 0.04b 24.56 ± 0.10a 23.67 ± 0.14b 22.27 ± 0.01c
Open in a new tab

Note: the data in the table represent the average ±SEM of three parallel treatments. Different lowercase letters indicate significant differences during different flooding times (p < 0.05).

Microbial community structure in tea plantation soil

Microbial community diversity

Compared with other flooding times, the Chao1 index of soil bacteria in the 15-day flooding treatment was significantly higher than other flooding times, and the Chao1 index of soil fungi in the 27-day flooding treatment was significantly higher than other flooding times. The Chao1 index of soil fungi in the 15-day flooding treatment showed the second advantage (Figures 2A and 2E). Among them, after 15 days of flooding treatment, the unique OTU number of soil bacteria was 5,745, which was 2,582 and 1,452 higher than that of 0 and 27 days, respectively (Figure 2B). Soil fungi had a unique OTU count of 357 after 15 days of flooding treatment, which was 128 higher than that of 0 days (Figure 2F). Principal-component analysis (PCA) analysis of soil bacteria and fungi showed that the first and second principal components of soil bacteria explained 52.5% and 22.9% of all variation, respectively (Figures 2C and 2D), while those of soil fungi explained 50.6% and 23.1% of all variation, respectively (Figures 2G and 2H), indicating a significant influence of flooding duration on soil bacterial and fungal community structure.

Figure 2.

Figure 2

Open in a new tab

Alpha and beta diversity of soil bacterial and fungal communities across flooding durations

(A–H) The α diversity of bacteria (A). Venn diagram showing the number of unique and shared OTUs among different bacterial treatments (B). The β-diversity of bacteria (PCA analysis) (C). The β-diversity of bacteria (boxplot); the alpha diversity of fungi (D). Error bars represent the distribution range of data subjects. Venn diagram showing the number of unique and shared OTUs among the various fungal treatments (F). The β-diversity of fungi (PCA analysis) (G). The β-diversity of fungi (boxplot) (H). Error bars represent the distribution range of data subjects.

Soil microbial community abundance

The compositions of soil bacterial and fungal communities at the phylum level under different treatments were analyzed, as shown in Figures 3A and 3D. Ten bacterial phyla were detected across all treatments, although with differences in relative abundance. The phylum Proteobacteria was the dominant bacterial phylum in flooded soil, with the highest relative abundance observed after 15 days of flooding treatment (37.36%), followed by after 0 (34.69%), 27 (33.59%), 24 (32.65%), 21 (28.08%), and 18 days (27.99%). Acidobacteria was the second most dominant bacterial phylum, with the following order of relative abundance across treatments: 0 > 18 > 15 > 21 > 24 > 27 days (30.40%, 28.09%, 27.28%, 24.57%, 24.54%, 23.43%, respectively). Additionally, the phyla Chloroflexi and Actinobacteriota were the dominant phyla in flooded soil (relative abundance >10%) (Figures 3A and 3B).

Figure 3.

Figure 3

Open in a new tab

Relative abundance and differential taxa of soil microbial communities at the phylum level

(A–F) The relative abundance at the bacterial phylum level (A), bacterial LEfSe analysis (B), species composition heatmap at the bacterial phylum level (C), the relative abundance at the fungal kingdom level (D), fungal LEfSe analysis (E), and species composition heatmap at the fungal kingdom level (F).

Heatmap analysis further revealed that soil bacterial communities were enriched primarily with Actinobacteria, Acidobacteria, Firmicutes, Elusimicrobia, Verrucomicrobia, Proteobacteria, FCPU426, Bacteroidetes, and Patescibacteria after 0 and 15 days of flooding, and they were enriched with Chloroflexi, GAL15, Cyanobacteria, Verrucomicrobia, Chlamydiae, Gemmatimonadetes, Armatimonadetes, Nitrospirae, and Acidibacter after 18 and 21 days of flooding. Additionally, soil bacterial communities were enriched primarily with Cyanobacteria, Euryarchaeota, Actinobacteria, WPS_2, Dependentiae, and Elusimicrobia after 24 and 27 days of flooding (Figure 3C).

The fungi in the tea plantation soil are divided into two dominant phyla, Ascomycota and Basidiomycota. The relative abundance of fungal phyla varies under different waterlogging treatments. Among them, the relative abundance of Ascomycota is the highest. Specifically, the highest relative abundance (94.02%) was observed after 24 days of waterlogging, followed by 15 (81.33%), 0 (78.98%), 27 (56.39%), and 18 days (45.10%). The second dominant phylum is Basidiomycota, which accounted for 19.62%, 14.51%, 28.04%, and 3.61% of the fungal phyla under the 0, 15, 18, and 24 days treatments, respectively (Figure 3D). Additionally, under the no waterlogging treatment, Coniochaetales and Coniochaeticeae, as well as Branch06, Ophiocordycipitaceae, Purpureocillium, and Staphylotrichum, had significantly higher relative abundances after 18 and 21 days of flooding. The results of the heatmap analysis further indicated that after 0 and 15 days of waterlogging, the soil fungal community was mainly enriched in Ascomycota and Basidiomycota; after 18 and 21 days, it was enriched in Entorrhizomycota, Kickxellomycota, Ascomycota, and Basidiomycota; and after 24 and 21 days, it was enriched in Mortierellomycota, Mucoromycota, Chytridiomycota, Rozellomycota, Calcarisporiellomycota, and Olpidiomycota (Figure 3F).

Correlation between soil chemical properties and microbial communities

Detrended correspondence analysis (DCA) results indicated that the lengths of gradient on the first axis were <3. RDA elucidated the impact of soil chemical properties on untreated soil microbial communities (Figure 4). In bacteria, soil environmental factors accounted for a total of 77.85% of the variation in soil bacterial community structure. Out of this, RDA1 explained 62% of the variation, while RDA2 explained 15.85% (Figure 4A). Additionally, soil environmental factors accounted for 92.24% of the variation in soil fungal community structure, and RDA1 and RDA2 explained 78.76% and 13.48% of the variation, respectively (Figure 4B).

Figure 4.

Figure 4

Open in a new tab

Redundance analysis of soil bacterial and fungal communities and environmental factors

(A and B) Analysis of the RDA between nutrient factors and heavy metal elements and the bacterial community structure (A). Analysis of the RDA between nutrient factors and heavy metal elements and the fungal community structure (B).

Further analysis of the influence of soil environmental factors on bacterial and fungal community composition was conducted by correlating annotated OTUs at the genus level with environmental factors using a correlation heatmap (Figure 5). The results indicated significant impacts of various environmental factors on both bacterial and fungal community composition (Figure 5).

Figure 5.

Figure 5

Open in a new tab

Heatmap analysis of the correlation between bacterial and fungal communities and environmental factors

(A and B) Heatmap analysis of the correlations between nutrient factors and heavy metal elements and bacterial communities (A). Heatmap analysis of the correlations between nutrient factors and heavy metal elements and fungal communities (B). Red indicates a positive correlation, with darker colors indicating a stronger correlation; blue indicates a negative correlation, with darker colors indicating a stronger negative correlation. Asterisk indicates significant difference test; ∗p < 0.05,∗∗p < 0.01,∗∗∗p < 0.001.

Correlation analysis between soil environmental factors and bacterial community revealed significant negative correlations of pH and K with Acidothermus and WPS-2, significant positive correlations with Candidatus Solibacter, significant positive correlations of K with Acidibacter, and significant negative correlations with Subgroup-13. Additionally, Cd exhibited significant positive correlation with Acidibacter, whereas Cu and Cr exhibited significant positive correlations with Subgroup-13, and Pb exhibited significant positive correlations with Subgroup-13 and Candidatus Solibacter, as well as significant negative correlation with Subgroup-13, and significant positive correlation with Candidatus Solibacter. Moreover, Hg exhibited significant positive correlation with WPS-2. In addition, Zn exhibited significant positive correlation with WPS-2 and significant negative correlation with Candidatus Solibacter (p < 0.05) (Figure 5A).

Correlation analysis between soil environmental factors and fungal community revealed significant positive correlations of Cu with Lophotrichous and Acaulium, significant positive correlation of Cr with Lophotrichus, significant positive correlations of As with Lophotrichus and significant negative correlations with Humicola and Corallomycetella. Additionally, Ni exhibited significant negative correlations with Humicola and Corallomycetella, while OM exhibited significant positive correlation with Metarhizium and significant negative correlations with Talaromyces and Xylogone. Furthermore, N and P concentrations exhibited significant positive correlations with Metarhizium and Pb exhibited significant positive correlations with Metarhizium and significant negative correlations with Talaromyces. In addition, Cd had significant positive correlation with Metarhizium, and Zn had significant positive correlations with Talaromyces and Xylogone. Lastly, Hg had significant positive correlation with Xylogone (p < 0.05) (Figure 5B).

Discussion

Changes in soil chemical properties

Variations in soil moisture content lead to alterations in soil properties such as pH, redox potential, metal oxides, and OM.18 In this study, the initial stage of flooding significantly increased the levels of AN, AP, AK, soil pH, and OM content. This is attributed to the fact that flooding treatment may enhance the decomposition and mineralization of OM, thereby releasing more available nutrients.19,20,21,22 However, as the duration of flooding extended, the increasing trend of these nutrients gradually weakened and eventually declined. Soil pH and OM content exhibited similar trends, consistent with the findings of Miao Tingting et al. and Huang Yanli et al., who reported a decrease in soil nutrient content after flooding.10,23 Furthermore, prolonged flooding reduces oxygen supply in the soil, potentially leading to a decline in microbial activity and subsequently slowing the rate of nutrient release.24,25 Additionally, although flooding treatment significantly increased soil pH to 4.73 ± 0.01, the soil remained acidic, indicating that short-term flooding may not effectively alleviate soil acidification in tea plantations. Long-term flooding could enhance soil reducibility, further exacerbating soil acidification issues.26,27

Heavy metals in tea plantation soils

Heavy metals exert significant effects on the physiological activities of tea plants, particularly when their concentrations in the soil exceed certain thresholds, leading to severe inhibition of tea plant growth.28 In this study, following flooding treatment, the concentrations of heavy metals in the tea plantation soil initially increased and then decreased. Tea plants exhibit low tolerance to heavy metals, with Pb and Cd notably having significant negative impacts on their growth and quality. The flooding treatment likely altered the soil’s redox conditions, thereby influencing the bioavailability of heavy metals.29,30 The concentrations of Cu, Pb, Cd, Hg, Zn, and Ni in the tea plantation soil did not exceed the risk screening values for non-paddy agricultural land. However, the concentrations of Cr and As reached 164.67 ± 0.52 mg kg−1 and 40.76 ± 0.36 mg kg−1, respectively, after 18 days of flooding, indicating slight contamination by Cr and As. This phenomenon may be attributed to the leaching of heavy metals caused by flooding, which facilitated their downward migration and increased the risk of groundwater contamination. Particularly under acidic soil conditions, the solubility and mobility of heavy metals are enhanced.31,32 Heavy metals affect the physiological activities of tea plants, as metal ions can chelate compounds such as amino acids and proteins, in turn reducing their supply to plants.33 When the concentrations of heavy metals in tea plantation soil exceeds a certain level, the growth of tea trees would be affected severely.34 Following treatment with Pb, tea plants exhibited leaf chlorosis and wilting, weakened sprouting ability, and reduced shoot size, with significant decrease in tea plant biomass.35 Compared to other ecosystems, tea trees are perennial evergreen woody plants with sparse strip planting, with root depths of 30–50 cm. They are more sensitive to surface redox changes than field crops, and their target product is “fresh leaves.” Any heavy metal or metabolic stress can be directly transmitted to the human food chain, and the safety threshold is stricter than that of food crops.36 Compared to other crops, tea soil needs to maintain an “acidic window” of pH 4.5–5.5. Once flooded, it can cause a sudden increase in pH or metal activation, making it difficult to repair through crop rotation. In addition, tea plantations are more sensitive to Cr and As activation due to acidic substrates and deep root systems, but due to high organic matter fixation, the peak soil concentration after flooding is actually lower than that of neutral corn fields.23 Although Cr (164.7 mg kg−1) and As (40.8 mg kg−1) at 18 days were only slightly higher than the screening values of GB 15618-2018, their peaks then dropped rapidly, indicating a short risk period, and the Cr in acidic red soil was mainly low-toxicity Cr(III). The bioavailability of As decreased after re-adsorption with Fe/Al oxides.37 Furthermore, referring to the report by Barman et al. on the same type of red soil tea plantation, the soil-tea enrichment coefficient (BCF) was generally less than 0.02, which was much lower than that of staple crops such As rice. Correspondingly, the theoretical contents of Cr and As in fresh leaves were lower than 0.07 mg kg−1, still lower than 5 mg kg−1 (Cr) and 0.5 mg kg−1 (As) stipulated in “Limits of Contaminants in Tea” (GB 2762-2022).38 Therefore, instant picking materials are safe but suggest to downhill catchment tea plantation for intermittent drainage (18 days or less) and monitoring of pore water every 3 years, to prevent Cr(VI) or As(V) from migrating downward.

Soil microbial community structure in tea plantations

Flooding treatment significantly influenced the diversity and structure of soil microbial communities in tea plantations. Short-term flooding (15 days) markedly increased the Chao1 index of soil bacteria and fungi, indicating an enhancement in microbial diversity during the initial flooding period. However, prolonged flooding led to significant alterations in microbial community structure, particularly in the relative abundances of Proteobacteria and Ascomycota, which varied notably with different flooding durations. Soil chemical properties, such as OM and AK content, had a pronounced impact on microbial community structure. The decomposition and mineralization of OM likely provided additional carbon and energy sources for microorganisms, fostering the growth of certain microbial groups.39 Conversely, extended flooding may result in the enrichment of anaerobic microorganisms, suppressing the growth of aerobic species.40

Redundancy analysis (RDA) revealed that soil chemical properties accounted for a substantial portion of the variation in microbial community structure, with OM and AK content being the most influential factors for both bacterial and fungal communities. This is attributed to OM serving as the primary carbon and energy source for microbial growth41 and AK being an essential nutrient for microbial development.42 Additionally, heavy metals (e.g., Cd, Pb, and Cr) significantly affected microbial communities, potentially leading to the reduction of sensitive species and the enrichment of metal-tolerant microorganisms. For instance, the abundance of Proteobacteria was positively correlated with AN, AP, AK, Pb, Cd, Cr, As, and Hg concentrations, while Ascomycota abundance showed positive correlations with AK, Cd, and Ni concentrations.

At the phylum level, Proteobacteria, Acidobacterita, Chloroflexi, and Actinobacteriota were the dominant bacterial phyla in the soil. Acidobacterita exhibited the highest relative abundance in the 0-day flooding treatment, suggesting its potential role in nutrient-limited environments, particularly in the degradation of plant residues’ cellulose and lignin within the carbon cycle.43 Chloroflexi reached its peak relative abundance in the 21-day flooding treatment, indicating its possible significance in the biogeochemical cycling of elements such as C, N, and S.44

Regarding fungal communities, Ascomycota predominated in the 24-day flooding treatment, whereas Basidiomycota was most abundant in the 18-day flooding treatment. Ascomycota demonstrated strong OM degradation capabilities, especially under low-nutrient conditions,45 while Basidiomycota played a crucial role in lignin and cellulose degradation.46

Further analysis identified AK, OM, Cr, and As as key environmental factors influencing fungal communities in flooded soils. Different studies have proposed varying dominant environmental factors driving changes in fungal communities in tea plantations. For example, in organically mulched tea plantations, soil moisture content and available nitrogen were key factors,47 whereas in those with organic fertilizer application, soil organic carbon (SOC), microbial biomass carbon (MBC), and AK were critical.48 Moreover, pH had a greater impact on bacterial communities than on fungal communities.49 These findings suggest that agricultural management practices significantly affect microbial community composition and function by altering soil physicochemical properties, thereby driving the restructuring of microbial communities.

The reason for the rapid increase in Proteobacteria may be because this group contains a large number of facultative anaerobic bacteria (such as Pseudomonas and Rhizobium), which can quickly switch to nitrate respiration after a sudden drop in O2, gaining energy advantages. RDA showed a significant positive correlation (p < 0.05) between Proteobacteria and AN, AP, K, Pb, Cd, etc., indicating that it not only benefits from nutrient pulses but may also participate in heavy metal biotransformation (such as reduction of Cr(VI), methylation of As), thereby further consolidating its ecological niche.50 Similarly, most members of Chloroflexi are obligate or facultative anaerobic “slow fermentation bacteria” that are adept at degrading recalcitrant OM such as cellulose and lignin. Their peak abundance coincides with the second decline of OM, indicating their role in “late stage carbon recovery.” Chloroflexi can participate in denitrification and Fe (III) reduction, serving as an “electron transfer hub” in the iron–carbon coupled cycle, helping the system maintain redox balance.50 Both RDA and ABT in this study indicate a significant positive correlation between Chloroflexi and Cr and As, suggesting that it indirectly reduces plant availability by forming anaerobic biofilms to fix or reduce these metals. Short-term (≤15 days) flooding: Proteobacteria dominates, driving “rapid nutrient cycling+potential metal detoxification” to provide quick-acting nitrogen and phosphorus for tea trees. Medium- to long-term (≥21 days) flooding: Chloroflexi takes over, promoting “stubborn carbon degradation+anaerobic metal reduction,” slowing down the continuous decline of redox potential, and maintaining microbial network stability. Therefore, the successive advantage of the two is a functional indicator of the transition of tea plantation soil from “aerobic facultative” to “anaerobic fermentation,” which can be used as a microbial indicator group to evaluate the flood resilience of tea plantation.

This study systematically reveals, for the first time, the multidimensional impacts of natural rainfall-induced flooding on tea plantation soils. The findings demonstrate that flooding duration significantly regulates the dynamic changes in soil nutrients and heavy metals. Short-term flooding (15–18 days) promotes an increase in soil pH, organic matter, and available nutrients, whereas prolonged flooding leads to their subsequent decline and is accompanied by slight exceedances of Cr and As, suggesting that flooding may enhance heavy metal mobility and ecological risk. Concurrently, flooding significantly alters microbial community structure: short-term flooding enhances microbial diversity, while long-term flooding reinforces bacterial communities dominated by Proteobacteria and fungal communities dominated by Ascomycota and Basidiomycota. Bacterial communities are primarily driven by organic matter, available potassium, and pH, whereas fungal communities are mainly influenced by available potassium, organic matter, Cr, and As. In summary, flooding synchronously regulates the dynamics of soil nutrients and heavy metals as well as microbial community functions by modifying key environmental factors, providing a theoretical basis for assessing tea plantation soil health, and developing flooding management strategies.

Limitations of the study

This research was a single-site experiment conducted in a red soil tea plantation in Yingde, Guangdong, with the parent material being granite weathering crust and a background soil pH of 5.2.51 Therefore, the research conclusions should be applied with caution to other tea-growing areas with granite, sandstone, shale, or Quaternary red soil parent materials, as the background content of heavy metals and soil buffering capacity in these areas may differ significantly and direct extrapolation is not advisable. Additionally, the continuous rainfall in June 2022 was an extreme meteorological event that occurs once every 30 years. This uncontrollable factor limited the repeated verification of different intensities or intermittent flooding processes, which may have led to an overestimation of the extent of metal leaching. Prior to the research, the experimental site had been managed using “organic fertilizer+formula fertilizer” for several consecutive years.52 If different management measures such as long-term avoidance of organic fertilizers or excessive phosphorus fertilizer application were adopted in the tea plantation, it would change the content of iron and aluminum oxides in the soil, thereby affecting the release patterns of elements such as chromium and arsenic.53 Moreover, the sampling depth in this study was limited to the 0–20 cm surface soil, and the migration of heavy metals to deeper layers below 30 cm and their potential impact on groundwater were not evaluated. Future research should conduct multi-scale validations under different parent materials, management conditions, and meteorological backgrounds and strengthen the monitoring of the migration process in deep soil and groundwater to more comprehensively assess the migration patterns and ecological risks of heavy metals in tea plantation. Furthermore, given the potential for Cr and As to translocate into fresh leaves, future work should directly determine Cr(VI) and total As concentrations in tea shoots under varying flooding durations and establish a dynamic transfer model with soil levels to more accurately assess food-safety thresholds.

Resource availability

Lead contact

Requests for further information and resources should be directed to and will be fulfilled by the lead contact, Dongxia Liang (liangdx3407@163.com).

Materials availability

This study did not generate new unique reagents.

Data and code availability

  • •The data supporting the findings of this study are availability within the manuscript and the supplemental information.

  • •This paper does not report the original code.

  • •Any additional information required is available upon reasonable request to the lead contact.

Acknowledgments

This research was funded by the Innovative Team Construction Project of Modern Agricultural Industrial Technology System in Guangdong Province with Agricultural Products as Unit (Tea Industry Technology System) (2024CXTD11), Modern Agricultural Industry Technology System Innovation Team Construction Project of Guangdong Province with Agricultural Products as Unit (Tea) (Project Code:2024KJ120), Guangzhou Science and technology planning project (Project Code:2023E04J1267), and Guangdong Academy of Agricultural Sciences Innovation Fund – Industry special project (Project Code:202303).

Author contributions

All authors contributed to the study conception and design. Conceptualization, C.L.; writing—original draft, C.L., D.L., and L.G.; investigation, C.L. and Q.Z.; formal analysis, C.L.; methodology, D.L.; data curation, D.L.; funding acquisition, H.H.; writing—review & editing, H.H.

Declaration of interests

The authors declare no competing interests.

STAR★Methods

Key resources table

REAGENT or RESOURCE SOURCE IDENTIFIER
Chemicals, peptides, and recombinant proteins
Nanodrop Thermo Scientific NC2000
Electrophoresis apparatus Beijing Liuyi Instrument Factory DYY-6C
Gel imaging system Beijing Baijing Instrument Factory BG-gdsAUTO(130)
Agarose Invitrogen 75510–019
Marker Takara DL15000 or DL2000
TAE Invitrogen AM9870
Grinding equipment Shanghai Jingxin Tissuelyser-48
HCl Chronchem 7647-01-0
HNO3 Chronchem 7697-37-2
HF Chronchem 7664-39-3
La(NO3)3·6H2O Chronchem 10277-43-7
HClO4 Chronchem 7601-90-3
H2SO4 Chronchem 7664-93-8
KI Chronchem 7681-11-0
SnCl2·2H2O Chronchem 10025-69-1
CuSO4·5H2O Chronchem 7758-99-8
Pb(CH3COO)2·5H2O Chronchem 6080-56-4
C4H10NS2Ag Chronchem 1470-61-7
((HOCH2CH3)3N) Chronchem 102-71-6
CHCl3 Chronchem 67-66-3
NaOH Chronchem 1310-73-2
K2CrO7 Chronchem 7778-50-9
KMnO4 Chronchem 7722-64-7
NH2OH·HCl Chronchem 5470-11-1
V2O5 Chronchem 1314-62-1
FeSO4·7H2O Chronchem 7782-63-0
C8H4K2OSb2 Chronchem 28300-74-5
C6H8O6 Chronchem 50-81-7
FH4N Chronchem 12125-01-8
NaHCO3 Chronchem 144-55-8
NH4C2H3O2 Chronchem 631-61-8
Open in a new tab

Method details

Overview of the experimental area

The experimental site was located at the Yingde Experimental Base of the Tea Research Institute, Guangdong Academy of Ag-ricultural Sciences, Kengkouzui, Yingde City, Qingyuan City, Guangdong Province, China (longitude 113°39′59″, latitude 24°30′62″), at an altitude of 30 m. The area experiences a south Asian monsoon climate characterized by warm and rainy weather, without severe cold or extreme heat. The annual average temperature is 20.7°C, with an average annual rainfall of 1876.8 mm distributed over 162 days. The average relative humidity is 79.0%, and there are 316.7 frost-free days annually. The soil is classified as red soil, and its basic physicochemical properties are listed in Table 1. According to the GB 15618-2018 “Soil Environmental Quality Standard for Agricultural Land Soil Pollution Risk Control (Trial)” regulations, the contents of Cu, Pb, Cd, Cr, As, Hg, Zn, and Ni contents do not exceed the screening values for non-paddy agricultural land soil pollution risk with a pH ≤ 5.5 (Table 2).

Experimental design

In order to explore the effects of different flooding time after natural rainfall (flood conditions) on the physical and chemical properties, heavy metals and microbial community structure of tea plantation soil, this experiment used natural rainfall to treat the tea plantation soil with flooding. According to the local rainfall conditions, 27 days of continuous rainfall in June 2022 were selected for the test to ensure that the test was conducted under suitable natural rainfall conditions. Therefore, a 27 days tea plantation soil flooding experiment was carried out. During the experiment, a total of 5 PVC water level gauges (with an accuracy of 1 mm) are arranged at the four corners and the center of the community, and the water depth is recorded at 08:00 and 16:00 every day. During the experiment, the tea plantation soil was completely submerged, and the flooding depth was more than 0.5 m high. Specifically, the field experiment was carried out in a 20 m2 (10 m × 2 m) tea plantation micro area. The experiment used a completely randomized block design, including 6 treatments with 3 replicates for each treatment, and a total of 18 microregions. The experimental design was as follows: CK (control group, flooding 0 days), T1 (flooding 15 days), T2 (flooding 18 days), T3 (flooding 21 days), T4 (flooding 24 days), T5 (flooding 27 days). 1 m protective row is set around the test area, and 0.5 m wide drainage ditch is set between the communities. After the water was completely drained, 0–20 cm depth soil samples were collected from different areas in the tea plantation (The layout of the test area is shown in Figure 1). The soil cultivation and management measures of tea plantation after water withdrawal are consistent with the local field production and management measures.

Determination of basic soil chemical properties

Each experimental plot underwent composite sampling at five points to collect surface soil (0–20 cm) from different areas. Plant debris and gravel were removed, and the soil samples were air-dried in a shaded area before being ground and sieved (2 mm). The physicochemical properties of the soil were then determined. Microbiological analysis samples were frozen at −80°C within 24 h; Physicochemical and heavy metal samples are dried at room temperature and ground for standby. Soil nutrient contents were determined according to Bao Shidan’s “Soil Agrochemical Analysis”54 and Lu Rukun’s “Soil Agrochemical Analysis Methods”,55 as follows. Soil pH was measured using the potentiometric method (soil-water ratio of 1:2.5) Soil OM content was determined using the potassium dichromate volumetric method, and alkali-hydrolyzable nitrogen (AN) content was determined using the alkali diffusion method. AP and AK contents were determined using the hydrochloric acid-ammonium fluoride extraction-molybdenum antimony anti-colorimetric method and the ammonium acetate extraction-flame photometric method, respectively.

Soil heavy metal concentration determination

Soil samples were digested with a mixture of concentrated acids (HCl–HNO3–HF, USEPA 3052 method) and the soil Cd and Pb contents were determined using graphite furnace atomic absorption spectrophotometry, whereas soil Cu, Cr, Zn, and Ni contents were determined using flame atomic absorption spectrophotometry. To determine soil Hg and As contents, soil samples were di-gested with aqua regia, followed by atomic fluorescence spectrometry.

Determination of soil microbial diversity

According to the instructions provided by MP Biomedicals, Santa Ana, CA, DNA was extracted from soil samples using the Fast DNA Spin Kit for Soil. Sequencing primers targeting the bacterial 16S rRNA V3∼V4 region (338F: 5′-ACTCCTACGGGAGGCAGCA-3'/806R: 5′-GGACTACHVGGGTWTCTAAT-3′) and the fungal ITS region (ITS5F: 5′-GGAAGTAAAAGTCGTAACAAGG-3'/ITS2: 5′-GCTGCGTTCTTCATCGATGC-3′) were selected for PCR amplification. The PCR amplification conditions were as follows: 98°C for 5 min (initial denaturation); 98°C for 10 s; 50°C for 30 s; 72°C for 30 s (25 cycles); and 72°C for 5 min (final extension).56 The PCR products were purified, quantified, and normalized to construct sequencing libraries. Libraries that passed quality control were subjected to paired-end (PE) high-throughput sequencing on the Illumina NovaSeq-PE250 platform (Illumina, Inc., San Diego, CA, USA). Fungal diversity analysis was performed according to the standard protocols of Personalbio Technology Co., Ltd. (Shanghai, China).

Quantification and statistical analysis

Alpha diversity indexes, including Chao1, Shannon, Simpson, and observed species, were calculated using QIIME2 (2019.4; https://www.genescloud.cn/home). In the analysis of alpha diversity, the Chao1 index is particularly emphasized because it is particularly effective in estimating species richness, especially in microbial communities with high diversity and uneven abundance distribution. The Chao1 index reflects species richness, and the larger the value, the higher the species richness in the community.57 The Chao1 index is sensitive to rare species and can provide a reliable estimate of the total number of operable taxonomic units (OTUs) in the sample, which is crucial for understanding microbial diversity in soil ecosystems. Therefore, it is particularly emphasized.58 Principal Component Analysis (PCA) and analysis of differences between groups using Permutational Multivariate Analysis of Variance were conducted to estimate the beta diversity index of bacterial communities in different treatments.59 Linear Discriminant Analysis coupled with Effect Size was used to determine the species with significant differences in relative abundance among different treatments.60 16S rRNA gene sequences were used to predict metabolic pathways using PICRUSt2 in the Kyoto Encyclopedia of Genes and Genomes database. Redundancy analysis (RDA) analysis and Heatmap correlation analysis between soil properties and microbial communities were completed using Wekemo Bioincloud (https://www.bioincloud.tech).

All statistical analyses were performed using IBM SPSS Statistics 21 (IBM Corp., Armonk, NY, USA) and visualization was performed using Origin 2021b (OriginLab, Northampton, MA, USA). One-way ANOVA followed by Tukey’s multiple comparisons test were used to evaluate the differences more than two group. The data are presented as the means ± SEM. Different lowercase letters indicate significant differences (p < 0.05).

Published: January 8, 2026

Footnotes

Supplemental information can be found online at https://doi.org/10.1016/j.isci.2026.114650.

Supplemental information

Document S1. Figure S1
mmc1.pdf (188.7KB, pdf)

References

  • 1.Liu Z., Chen Z., Yang Y., Jiang R. Innovation Drives High-quality Development of Chinese Tea Industry from Basic Research of Tea Science to Supporting Industrial Development. China Tea. 2021;43:1–9. [Google Scholar]
  • 2.Qiu Q., Fan D., Wang Y., Huang D., Wang Y., Ma J., Wang X. Effect of calcium cyanamide on soil fungal community in successive tea-cuttings nursery. Agriculture. 2021;11:716–732. doi: 10.3390/agriculture11080716. [DOI] [Google Scholar]
  • 3.Liu Q., Li X., He L. Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, China. Front. Chem. 2022;10:10988587–10988597. doi: 10.3389/fchem.2022.988587. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 4.Wang Y., Wu T., Zhou D., Chen H. Advances in soil heavy metal pollution evaluation based on bibliometrics analysis. Journal of Agro-Environment Science. 2017;36:2365–2378. [Google Scholar]
  • 5.Gong X., Shi J., Zhou X., Yuan T., Gao D., Wu F. Crop Rotation With Cress Increases Cucumber Yields by Regulating the Composition of the Rhizosphere Soil Microbial Community. Front. Microbiol. 2021;12:631882–631894. doi: 10.3389/fmicb.2021.631882. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Zhang X., Huang C., Meng Y., Liu X., Gao Y., Liu Z., Ma S. Physiological Mechanism of Waterlogging Stress on Yield of Waxy Maize at the Jointing Stage. Plants. 2023;12:3034–3047. doi: 10.3390/plants12173034. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 7.He Q. Effect of flooding on leaching behavior of heavy metals in soil and its mechanism. Environmental Pollution & Control. 2020;1:91–93. [Google Scholar]
  • 8.Hu C., Yan C., Guo L., Hao M., Mao Q., Yang S. Effects of flooding on soil organic carbon and dissolved organic carbon under extreme rainstorm. Chin. J. Eco-Agric. 2024;32:1322–1330. [Google Scholar]
  • 9.Ponting J., Kelly T.J., Verhoef A., Watts M.J., Sizmur T. The impact of increased flooding occurrence on the mobility of potentially toxic elements in floodplain soil-A review. Sci. Total Environ. 2021;754:142040–142054. doi: 10.1016/j.scitotenv.2020.142040. [DOI] [PubMed] [Google Scholar]
  • 10.Miao T., Wu Z., Liu J., Ding C., Cao Z., Sun H., Yan C., Yang C. The Impact of Seasonal Flooding on the Physicochemical Properties, Enzyme Activity, and Microbial Communities of Populus Forest Soil in the Yangtze River Floodplain. J. Northeast For. Univ. 2025;53:134–146. doi: 10.13759/j.cnki.dlxb.2025.01.012. [DOI] [Google Scholar]
  • 11.Unger I.M., Motavalli P.P., Muzika R.M. Changes in soil chemical properties with flooding: A field laboratory approach. Agric. Ecosyst. Environ. 2009;131:105–110. doi: 10.1016/j.agee.2008.09.013. [DOI] [Google Scholar]
  • 12.Zhang J., Li S., Sun X., Tong J., Fu Z., Li J. Sustainability of urban soil management: analysis of soil physicochemical properties and bacterial community structure under different green space types. Sustainability. 2019;11:1395–1411. doi: 10.3390/su11051395. [DOI] [Google Scholar]
  • 13.Devi R., Kaur T., Kour D., Rana K.L., Yadav A., Yadav A.N. Beneficial fungal communities from different habitats and their roles in plant growth promotion and soil health. Microbial Biosystems. 2020;5:21–47. doi: 10.21608/mb.2020.32802.1016. [DOI] [Google Scholar]
  • 14.Shen R., Lan Z., Jörg R., Ni M., Hu Q., Yan Z., Fang C., Jin B., Chen J. Flooding variations affect soil bacterial communities at the spatial and inter-annual scales. Sci. Total Environ. 2020;759:143471–143481. doi: 10.1016/j.scitotenv.2020.143471. [DOI] [PubMed] [Google Scholar]
  • 15.Tedersoo L., Bahram M., Põlme S., Kõljalg U., Yorou N.S., Wijesundera R., Villarreal Ruiz L., Vasco-Palacios A.M., Thu P.Q., Suija A., et al. Fungal biogeography. Global diversity and geography of soil fungi. Science. 2014;346 doi: 10.1126/science.aaa4269. [DOI] [PubMed] [Google Scholar]
  • 16.Liang X., Li M., He P., Qin X., Bei E., Li J., Liang M., Zeng M., Cheng F. Effects of Water Logging Stress on Fungal Diversity, Community Structure and Functional Composition in Rhizosphere Soils of Simmondsia chinensis Seedlings. Guangxi Forestry Science. 2024;53:170–177. doi: 10.19692/j.issn.1006-1126.20240205. [DOI] [Google Scholar]
  • 17.Nguyen L.T.T., Osanai Y., Anderson I.C., Bange M.P., Tissue D.T., Singh B.K. Flooding and prolonged drought have differential legacy impacts on soil nitrogen cycling, microbial communities and plant productivity. Plant Soil. 2018;431:371–387. doi: 10.1007/s11104-018-3774-7. [DOI] [Google Scholar]
  • 18.Boostani H.R., Hardie A.G., Najafi-Ghiri M., Khalili D. The effect of soil moisture regime and biochar application on lead (Pb) stabilization in a contaminated soil. Ecotoxicol. Environ. Saf. 2021;208:111626–111634. doi: 10.1016/j.ecoenv.2020.111626. [DOI] [PubMed] [Google Scholar]
  • 19.Liang J., Li S., Liu X., Feng Q. Effects of biochar on phosphorus release and adsorption characteristics from submerged soil. Acta Agriculturae Jiangxi. 2022;34:72–78. doi: 10.19386/j.cnki.jxnyxb.2022.12.012. [DOI] [Google Scholar]
  • 20.Liu B., Zhao W., Wen Z., Yang Y., Chang X., Zhu Z., Si R. Hydrochemical characteristics jointly determine the transport and cycling of soil carbon,nitrogen,and phosphorus in an arid Chinese wetland. JGR. Biogeosciences. 2020;125 doi: 10.1029/2020JG005697. [DOI] [Google Scholar]
  • 21.Zhang X., Tian S., Zeng L., Chen L., Zhang M., Liu K., Hu J., Liu C. Effects of litter addition from common greening tree species in northern China on organic carbon composition characteristics of urban soils. Plant Science Journal. 2024;42:140–149. [Google Scholar]
  • 22.Zhao N., Wang X., He J., Yang S., Zhen Q., Li M. Effects of Replacing chemical nitrogen fertilizer with organic fertilizer on active organic carbon fractions, enzyme activities, and crop yield in yellow soil. Environmental Science. 2024;45:4196–4205. doi: 10.13227/j.hjkx.202307222. [DOI] [PubMed] [Google Scholar]
  • 23.Huang Y., Su H., Huang P., Zhuang J., Zhou H. Changes of Soil Nutrients in Summer Corn Field during Different. J. Henan Agric. Sci. 2024;53:90–99. doi: 10.15933/j.cnki.1004-3268.2024.07.010. [DOI] [Google Scholar]
  • 24.Szukics U., Hackl E., Zechmeister-Boltenstern S., Sessitsch A. Rapid and dissimilar response of ammonia oxidizing archaea and bacteria to nitrogen and water amendment in two temperate forest soils. Microbiol. Res. 2012;167:103–109. doi: 10.1016/j.micres.2011.04.002. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Zhu D., Liu Y., Zhang L., Wang X., An Y., Li Y., Lin D. Effects of pH, Eh, Fe, and flooded time on available-Cd content after flooding of different kinds of soil. Journal of Agro-Environment Science. 2017;36:1508–1517. [Google Scholar]
  • 26.Zhu T., Sun P., Dang Q., Zhang J., Cai Z. Improvement of Degraded Greenhouse Vegetable Soil by Flooding and/or Amending Organic Materials. Acta Pedol. Sin. 2014;51:335–341. [Google Scholar]
  • 27.Zhu T.B., Zhang J.B., Cai Z.C. Effects of organic material amendment on vegetable soil nitrate content and nitrogenousgases emission under flooding condition. Chin. J. Appl. Ecol. 2012;23:109–114. doi: 10.13287/j.1001-9332.2012.0015. [DOI] [PubMed] [Google Scholar]
  • 28.Ju Y., Luo Z., Bi J., Liu C., Liu X. Transfer of heavy metals from soil to tea and the potential human health risk in a regional high geochemical background area in southwest china. Sci. Total Environ. 2024;908 doi: 10.1016/j.scitotenv.2023.168122. [DOI] [PubMed] [Google Scholar]
  • 29.Wang Z., Liu X., Liang X., Dai L., Li Z., Liu R., Zhao Y. Flooding-drainage regulate the availability and mobility process of Fe, Mn, Cd, and As at paddy soil. Sci. Total Environ. 2022;817:152898. doi: 10.1016/j.scitotenv.2021.152898. [DOI] [PubMed] [Google Scholar]
  • 30.Yang B., Luo H., Liu S., Han C., Song Q., Cao Y. Effect and mechanism of water inundation on the leaching behavfrior of heavy metals in contaminated soils. Chinese Journal of Environmental Engineering. 2019;13:936–943. [Google Scholar]
  • 31.Qu C., Chen W., Hu X., Cai P., Chen C., Yu X.Y., Huang Q. Heavy metal behaviour at mineral-organo interfaces: Mechanisms, modelling and influence factors. Environ. Int. 2019;131:104995–105009. doi: 10.1016/j.envint.2019.104995. [DOI] [PubMed] [Google Scholar]
  • 32.Song P., Xu D., Yue J., Ma Y., Dong S., Feng J. Recent advances in soil remediation technology for heavy metal contaminated sites: A critical review. Sci. Total Environ. 2022;838:156417–156434. doi: 10.1016/j.scitotenv.2022.156417. [DOI] [PubMed] [Google Scholar]
  • 33.Feng Z., Ji S., Ping J., Cui D. Recent advances in metabolomics for studying heavy metal stress in plants. Trends Anal. Chem. 2021;143:116402–116413. doi: 10.1016/j.trac.2021.116402. [DOI] [Google Scholar]
  • 34.Tao C., Song Y., Chen Z., Zhao W., Ji J., Shen N., Ayoko G.A., Frost R.L. Geological load and health risk of heavy metals uptake by tea from soil: What are the significant influencing factors? Catena. 2021;204:105419–105431. doi: 10.1016/j.catena.2021.105419. [DOI] [Google Scholar]
  • 35.Wu Y., Li Q.H., Tang Q. Effect of Pb on growth, accumulation and quality component of tea plant. Procedia Eng. 2011;18:214–219. doi: 10.1016/j.proeng.2011.11.034. [DOI] [Google Scholar]
  • 36.Liu M., Yi X., Shi Y., Ma L., Ruan J. Research Progress of Soil Properties in Tea Gardens and Absorption and Translocation Mechanisms of Nutrients and Other Elements in Tea Plant. Journal of Tea Plant. Tea Science. 2015;35:110–120. doi: 10.13305/j.cnki.jts.2015.02.002. [DOI] [Google Scholar]
  • 37.Qin X., Desmau M., Guinoiseau D., Rovezzi M., Gélabert A., Ren Z., Benedetti M.F. Unveiling chromium dynamics: XANES spectroscopy insights in two Fe-Mn nodule-rich red soil profiles. J. Hazard. Mater. 2025;500 doi: 10.1016/J.JHAZMAT.2025.140547. [DOI] [PubMed] [Google Scholar]
  • 38.Barman T., Barooah A.K., Goswami B.C., Sharma N., Panja S., Khare P., Karak T. Contents of Chromium and Arsenic in Tea (Camellia sinensis L.): Extent of Transfer into Tea Infusion and Health Consequence. Biol. Trace Elem. Res. 2020;196:318–329. doi: 10.1007/s12011-019-01889-y. [DOI] [PubMed] [Google Scholar]
  • 39.Dong X., Wang J., Tian L., Lou B., Zhang X., Liu T., Liu X., Sun H. Review of relationships between soil aggregates, microorganisms and soil organic matter in salt-affected soil. Chin. J. Eco-Agric. 2023;31:364–372. doi: 10.12357/cjea.20220752. [DOI] [Google Scholar]
  • 40.Martínez-Arias C., Witzell J., Solla A., Martin J., Rodríguez-Calcerrada J. Beneficial and pathogenic plant-microbe interactions during flooding stress. Plant Cell Environ. 2022;45:2875–2897. doi: 10.1111/pce.14403. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 41.Bhattacharyya S.S., Ros G.H., Furtak K., Iqbal H.M.N., Parra-Saldívar R. Soil carbon sequestration-An interplay between soil microbial community and soil organic matter dynamics. Sci. Total Environ. 2022;815:152928. doi: 10.1016/j.scitotenv.2022.152928. [DOI] [PubMed] [Google Scholar]
  • 42.Jordi S., Josep P. Potassium Control of Plant Functions: Ecological and Agricultural Implications. Plants. 2021;10:419. doi: 10.3390/plants10020419. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 43.Ward N.L., Challacombe J.F., Janssen P.H., Henrissat B., Coutinho P.M., Wu M., Xie G., Haft D.H., Sait M., Badger J., et al. Three genomes from the phylum Acidobacteria provide insight into their lifestyles in soils. Appl. Environ. Microbiol. 2009;75:2046–2056. doi: 10.1128/aem.02294-08. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 44.Xian W., Zhang X., Li W. Research status and prospect on bacterial phylum Chloroflexi. Acta Microbiol. Sin. 2020;60:1801–1820. doi: 10.13343/j.cnki.wsxb.20200463. [DOI] [Google Scholar]
  • 45.Chen Y.L., Xu T.L., Veresoglou S.D., Hu H.W., Hao Z.P., Hu Y.J., Liu L., Deng Y., Rillig M.C., Chen B.D. Plant diversity represents the prevalent determinant of soil fungal community structure across temperate grasslands in northern China. Soil Biol. Biochem. 2017;110:12–21. doi: 10.1016/j.soilbio.2017.02.015. [DOI] [Google Scholar]
  • 46.Osono T., Takeda H. Fungal decomposition of Abies needle and Betula leaf litter. Mycologia. 2006;98:172–179. doi: 10.3852/mycologia.98.2.172. [DOI] [PubMed] [Google Scholar]
  • 47.Zhang S., Wang Y., Sun L., Qiu C., Ding Y., Gu H., Wang L., Wang Z., Ding Z. Organic mulching positively regulates the soil microbial communities and ecosystem functions in tea plantation. BMC Microbiol. 2020;20:103–115. doi: 10.1186/s12866-020-01794-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 48.Ji L., Ni K., Wu Z., Zhang J., Yi X., Yang X., Ling N., You Z., Guo S., Ruan J. Effect of organic substitution rates on soil quality and fungal community composition in a tea plantation with long-term fertilization. Biol. Fertil. Soils. 2020;56:633–646. doi: 10.1007/s00374-020-01439-y. [DOI] [Google Scholar]
  • 49.Fan D., Zhao Z., Wang Y., Ma J., Wang X. Crop-type-driven changes in polyphenols regulate soil nutrient availability and soil mi-crobiota. Front. Microbiol. 2022;13:964039–964056. doi: 10.3389/fmicb.2022.964039. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 50.de Freitas A.S., Carlos F.S., Martins G.L., Monteiro G.G.T.N., Roesch L.F.W. Bacterial Resilience and Community Shifts Under 11 Drainage Flooding Cycles in Rice Soil. Microb. Ecol. 2024;87:149. doi: 10.1007/s00248-024-02468-y. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 51.Tan X., Yun S., Liu S. Study on Soil Physical and Chemical Properties and Fertilization Measures of Red Soil High Yield Tea Plantations. CHINESE JOURNAL OF SOIL SCIENCE. 1987;1:1–3. doi: 10.19336/j.cnki.trtb.1987.01.010. [DOI] [Google Scholar]
  • 52.Li R., Lv Z., Zhou B., Cui Y. Study on soil acidification improvement and tea quality formation in the red tea area of northern Guangdong. Guangdong Tea Industry. 2024;6:7–14. [Google Scholar]
  • 53.Wang Q., Liu S., Ling C. Evaluation of Soil Quality and Heavy Metal Safety in Tea Garden of 13 Towns in Yingde, Guangdong. Chin. Agric. Sci. Bull. 2018;34:82–91. [Google Scholar]
  • 54.Bao S. China Agriculture Press; 2000. Soil Agrochemical Analysis. [Google Scholar]
  • 55.Lu R. China Agricultural Science and Technology Press; 2000. Soil Agrochemical Analysis Method. [Google Scholar]
  • 56.Wang Q., Feng X., Liu Y., Cui W., Sun Y., Zhang S., Wang F. Effects of microplastics and carbon nanotubes on soil geochemical properties and bacterial communities. J. Hazard. Mater. 2022;433:128826. doi: 10.1016/J.JHAZMAT.2022.128826. [DOI] [PubMed] [Google Scholar]
  • 57.Liu F., Peng L., Li C., Chen J., Sun X., Xiao Y., Li H., Gao R., Zhao T., Shu Q., et al. Effects of High-risk Herbicides on Bacterial Community Structure in Tobacco Field Soils with D.ifferent Texturest. Chin. Tobac. Sci. 2025;46:61–68. doi: 10.13496/j.issn.1007-5119.2025.05.008. [DOI] [Google Scholar]
  • 58.Haegeman B., Hamelin J., Moriarty J., Neal P., Dushoff J., Weitz J.S. Robust estimation of microbial diversity in theory and in practice. The ISME journal. 2013;7:1092–1101. doi: 10.1038/ismej.2013.10. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 59.Ramette A. Multivariate analyses in microbial ecology. FEMS Microbiol. Ecol. 2007;62:142–160. doi: 10.1111/j.1574-6941.2007.00375.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 60.Segata N., Izard J., Waldron L., Gevers D., Miropolsky L., Garrett W.S., Huttenhower C. Metagenomic biomarker discovery and explanation. Genome Biol. 2011;12:18. doi: 10.1186/gb-2011-12-6-r60. [DOI] [PMC free article] [PubMed] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Document S1. Figure S1
mmc1.pdf (188.7KB, pdf)

Data Availability Statement

  • •The data supporting the findings of this study are availability within the manuscript and the supplemental information.

  • •This paper does not report the original code.

  • •Any additional information required is available upon reasonable request to the lead contact.

Articles from iScience are provided here courtesy of Elsevier

RESOURCES