Key Takeaways & Executive Findings
- •• • Mixed forest soil exhibited the highest values for field water holding capacity, total porosity, saturated water content, total nitrogen, total carbon, available potassium, and available phosphorus, indicating superior soil physical and chemical properties compared to other vegetation types. • • Soil quality ranking: mixed forest > broad-leaved forest > shrub forest > economic forest > grassland > coniferous forest > abandoned cropland, with mixed forest significantly outperforming all others (p < 0.05). • • Compared to abandoned cropland, soil water content, total porosity, field water holding capacity, saturated water content, total carbon, total nitrogen, available potassium, and available phosphorus were significantly higher, while soil bulk density was significantly lower, demonstrating the positive impact of vegetation restoration on soil quality. • • Soil bulk density showed extremely significant negative correlations with soil water content, total porosity, and saturated water content (p < 0.01), and significant negative correlations with field water holding capacity, total carbon, and total nitrogen (p < 0.05), highlighting the critical role of soil compaction in nutrient and water retention.
Abstract
The effects of different vegetation types on soil quality in the Green Heart Area of the Changsha-Zhuzhou-Xiangtan City Cluster were evaluated to provide a reference for selecting suitable afforestation species and improving forest soil quality. Seven vegetation types (mixed forest, broad-leaved forest, coniferous forest, economic forest, shrub forest, grassland, and abandoned cropland) with similar site conditions were studied. Eleven soil physicochemical indicators were measured, and soil quality was assessed using principal component analysis (PCA), Pearson correlation, total data set (TDS), minimum data set (MDS), and entropy-weighted TOPSIS methods. Results showed no significant differences in soil water content, soil bulk density, and C:N ratio among vegetation types, while significant differences were found in total porosity, capillary porosity, saturated water content, field water holding capacity, total carbon, total nitrogen, available potassium, and available phosphorus. Compared with abandoned cropland, soil water content, total porosity, field water holding capacity, saturated water content, total carbon, total nitrogen, available potassium, and available phosphorus were significantly higher, and soil bulk density was significantly lower. Mixed forest soil exhibited the highest values for field water holding capacity, total porosity, saturated water content, total nitrogen, total carbon, available potassium, and available phosphorus. Correlation analysis revealed that soil bulk density was extremely significantly negatively correlated with soil water content, total porosity, and saturated water content, and significantly negatively correlated with field water holding capacity, total carbon, and total nitrogen. Soil capillary porosity, field water holding capacity, total porosity, and saturated water content were extremely significantly positively correlated with soil nutrients, while soil bulk density showed varying degrees of negative correlation with soil chemical nutrients. Soil chemical properties and stoichiometric ratios showed varying degrees of significant positive correlation. The order of soil quality under different vegetation types was mixed forest > broad-leaved forest > shrub forest > economic forest > grassland > coniferous forest > abandoned cropland. Mixed forest soil quality was the best and significantly higher than other vegetation types, with significant differences among vegetation types. Mixed forest soil quality was clearly superior. In vegetation restoration and plantation establishment in the Green Heart Area, the principle of matching tree species to site conditions should be followed, with a focus on mixed forests to improve overall soil quality and enhance ecological benefits of artificial vegetation restoration.
1. Introduction
The Green Heart Area of the Changsha-Zhuzhou-Xiangtan City Cluster, a critical ecological buffer in central China, faces soil degradation due to intensive land use and urbanization. Previous afforestation efforts have often relied on monocultures, which may not optimize soil quality. The selection of appropriate vegetation types is essential for enhancing soil health and ecosystem services. However, comprehensive evaluations comparing multiple vegetation types under similar site conditions are scarce, limiting evidence-based guidance for regional forest management.
This study addresses this gap by systematically assessing soil quality across seven vegetation types using a multi-method approach (PCA, TDS, MDS, entropy-weighted TOPSIS). By measuring 11 physicochemical indicators, we provide a robust comparison that identifies mixed forests as the most effective for improving soil properties. These findings offer actionable insights for afforestation strategies, emphasizing the need to prioritize mixed-species plantations to maximize soil quality and ecological benefits in urban green heart areas.
Loading authentic research manuscript (Pages 1–5)...
ZHOU Jinjin, TAO Liujun, HE Gongxiu, KONG Ting, MAN Qianru, PENG Jun (2026). Comprehensive Evaluation of Soil Quality under Different Vegetation Types in the Green Heart Area of the Changsha-Zhuzhou-Xiangtan City Cluster. Environmental Chemistry. https://doi.org/10.7524/j.issn.0254-6108.2024122406
Research & Educational Purpose Only: The translations, structured abstracts, analytical annotations, and data reports provided by SinoGreenTechare intended exclusively for academic research, internal corporate R&D, and educational benchmarking. They do not constitute formal engineering, chemical safety, legal, or professional advice.
Copyright & Intellectual Property Notice: Original copyright of the underlying source articles and experimental data remains with the respective authors, institutions, and original publishing journals. SinoGreenTech claims intellectual property only over its proprietary translations, analytical syntheses, and AEO structured enhancements in accordance with international fair use and academic citation principles.
Frequently Asked Questions
What specific soil physicochemical parameters were measured, and how were they selected for the evaluation?
Eleven soil physicochemical indicators were measured: soil water content, soil bulk density, total porosity, capillary porosity, saturated water content, field water holding capacity, total carbon, total nitrogen, available potassium, available phosphorus, and C:N ratio. These were selected to represent key physical, chemical, and fertility aspects of soil quality, and were analyzed using PCA to identify the most influential indicators for the minimum data set (MDS).
How did the soil quality of mixed forests compare quantitatively to that of abandoned cropland?
Mixed forest soil showed significantly higher values (p < 0.05) for field water holding capacity, total porosity, saturated water content, total nitrogen, total carbon, available potassium, and available phosphorus compared to abandoned cropland. For instance, total carbon and nitrogen were markedly elevated, while soil bulk density was significantly lower, indicating improved soil structure and fertility.
What statistical methods were employed to ensure the robustness of the soil quality ranking?
The study used principal component analysis (PCA) to reduce dimensionality, total data set (TDS) and minimum data set (MDS) to validate indicator selection, and entropy-weighted TOPSIS to compute comprehensive soil quality indices. Pearson correlation analysis was also performed to examine relationships among indicators. These methods collectively provided a robust and objective ranking of vegetation types.
Are there any limitations regarding the generalizability of these findings to other urban green heart areas?
The study was conducted in a specific region with particular climatic and soil conditions. While the methodology is transferable, the absolute values and rankings may vary with local factors such as soil type, climate, and land use history. However, the relative superiority of mixed forests is likely consistent, as they enhance soil structure and nutrient cycling through diverse litter inputs and root systems.
What practical recommendations can be derived for afforestation in the Green Heart Area?
The results strongly recommend prioritizing mixed-species plantations over monocultures to improve soil quality. Specifically, mixed forests should be favored, followed by broad-leaved forests and shrub forests, while coniferous forests and abandoned cropland are less effective. This aligns with the principle of matching tree species to site conditions and can guide future restoration projects to maximize ecological benefits.
Related Chinese Research & Cross-Citations
Exploring the Potential Molecular Mechanisms of Eight Environmental Pollutants in Lung Adenocarcinoma through Network Toxicology, Machine Learning, and Multi-Omics Analysis
Epidemiological studies have established a significant association between exposure to environmental pollutants (EP) and the risk of lung adenocarcinoma (LUAD). This study integrates network toxicology and multi-omics analysis to elucidate the EP-LUAD molecular regulatory network and identify key regulatory genes, thereby revealing novel mechanisms of environmental carcinogenesis. Transcriptomic data from GEO and TCGA databases yielded 4,971 and 4,488 disease-related targets, respectively. Integration of toxicology databases (TargetNet, Swiss Target Prediction, CTD, SEA) identified 24,860 potential targets for eight common pollutants (SO2, NO, CO, NO2, O3, benzene, toluene, and polycyclic aromatic hydrocarbons). Intersection of these datasets produced 1,536 EP-LUAD common target genes. Protein-protein interaction network analysis identified 247 core targets. Machine learning selected five key genes: AGER, CAV1, CD44, CEP55, and GNB3, which demonstrated robust diagnostic and prognostic efficacy. Their expression correlated with immune cell infiltration, including CD4+ memory T cells and macrophages. Single-cell RNA sequencing revealed epithelial cell-specific expression patterns. Molecular docking confirmed stable pollutant-target binding, with PAH showing highest affinity for CD44 (binding energy −9.32 kcal·mol−1) and GNB3 (−8.32 kcal·mol−1). These findings establish AGER, CAV1, CD44, CEP55, and GNB3 as core molecular mediators of pollution-related LUAD. The high-affinity binding of PAH to CD44 and GNB3 underscores its carcinogenic potential. This study constructs a multi-level regulatory network for EP-LUAD, revealing underlying molecular mechanisms and providing novel potential targets and theoretical basis for early warning and intervention.
Effects of Different Functionalized Nanoplastics on the Transformation of Extracellular Antibiotic Resistance Genes in Aquatic Environments
The rapid dissemination of antibiotic resistance genes (ARGs) in aquatic environments poses serious threats to public health and environmental safety under the 'One Health' framework. Nanoplastics (NPs), as co-occurring pollutants, can exacerbate ARG risks by promoting horizontal gene transfer (HGT), yet the influence of different functional groups on extracellular ARG (eARG) transformation remains unclear. This study investigated the effects of carboxy-modified polystyrene NPs (PS-COOH) and amino-functionalized polystyrene NPs (PS-NH2) compared to unmodified polystyrene NPs (PS) on the transformation of the extracellular resistance plasmid IE-V1955 (carrying an ampicillin resistance gene) into Escherichia coli DH5α. Results showed that PS-COOH exposure promoted plasmid transformation similarly to PS, with effects increasing over 0.1–20 mg·L−1. Low concentrations (0.1–0.5 mg·L−1) of PS-NH2 also enhanced transformation, with stronger effects than PS-COOH at equal doses, whereas high concentrations (1–20 mg·L−1) inhibited it. Mechanistically, PS-COOH (0.1–20 mg·L−1) and low PS-NH2 induced intracellular reactive oxygen species (ROS), increased cell membrane permeability, elevated the protein-to-polysaccharide ratio in extracellular polymeric substances (EPS), and promoted biofilm formation, thereby facilitating transformation. High PS-NH2 concentrations caused excessive ROS leading to cell lysis and formed aggregates with plasmids larger than membrane pores, blocking uptake. These findings provide a theoretical basis for assessing the combined environmental health risks of NPs and ARGs.
Cardiovascular Toxicity Induced by Micro/Nano-Plastics and Its Mechanisms
Micro/nano-plastics (MNPs) are emerging contaminants widely detected in human circulatory systems, including blood, heart, and vascular endothelium, raising concerns about cardiovascular health risks. This systematic review analyzed 61 peer-reviewed studies (2008–2024) to elucidate the cardiotoxic effects and molecular mechanisms of MNPs. Evidence indicates that MNPs exposure elevates risks of atherosclerosis, thrombosis, and arrhythmias through oxidative stress, inflammatory cascades, endothelial dysfunction, and metabolic dysregulation. Notably, co-exposure with persistent organic pollutants (POPs) or heavy metals may produce synergistic or antagonistic effects. Current research relies predominantly on animal and cell models, with critical gaps in low-dose, long-term exposure data and epidemiological evidence. Future studies should optimize experimental designs, integrate metabolomics and epigenetics, and explore transgenerational effects and combined toxicity mechanisms to inform pollution control policies and mitigate cardiovascular risks.
Body Burden of Polybrominated Diphenyl Ethers and Joint Effects on Thyroid Function in a Physical Examination Population in Shenzhen
This study characterized the body burden of polybrominated diphenyl ethers (PBDEs) in a physical examination population in Shenzhen and evaluated its impact on thyroid function. Serum samples from 368 residents were analyzed for eight PBDE congeners using atmospheric pressure gas chromatography-tandem mass spectrometry (APGC-MS/MS). The median concentration of ∑8PBDEs was 10.2 ng·g⁻¹ lipid weight (lw), ranging from 0.13 to 2089.4 ng·g⁻¹ lw, with BDE-209 predominating (59.7% of total). Multiple linear regression revealed that a 1.7-fold increase in serum BDE-153 was associated with a 0.4% increase in free triiodothyronine (FT3) (P<0.05), while a 1.7-fold increase in BDE-183 was associated with a 0.9% decrease in total triiodothyronine (T3) and a 0.7% decrease in FT3 (P<0.05). Bayesian kernel machine regression (BKMR) indicated a negative correlation between mixed PBDE exposure and thyroid-stimulating hormone (TSH) at high exposure levels. Weighted quantile sum (WQS) regression showed that mixed exposure was associated with decreased T3 levels and T3/FT3 ratio, with BDE-153 and BDE-183 as the primary contributors. These findings suggest that PBDE exposure may adversely affect thyroid function and disrupt thyroid hormone homeostasis, with BDE-183 and BDE-153 playing key roles. This study provides a scientific basis for PBDE health risk assessment and thyroid protection.
Mechanisms of Natural Organic Matter in Regulating Microplastic Aggregation and Transport in Soil-Groundwater Systems: A Review
Microplastics (MPs) are persistent emerging contaminants ubiquitously distributed in soil-groundwater environments, where their aggregation and transport critically govern pollutant fate and ecological risks. Natural organic matter (NOM), a complex assemblage of organic compounds, interacts with MPs and porous media via hydrogen bonding, π-π interactions, hydrophobic effects, and electrostatic binding, thereby modulating MP surface properties and environmental behavior. This review systematically synthesizes the mechanisms by which NOM influences MP aggregation and transport, with emphasis on the distinct roles of humic substances, proteins, and extracellular polymeric substances (EPS), and their synergistic modulation with solution chemistry (pH, ionic strength, ion type). Additionally, NOM accelerates MP aging and alters surface characteristics, consequently impacting transport capacity. Current research limitations are identified, and future directions are proposed to inform MP pollution risk assessment and management strategies. Key findings indicate that NOM generally enhances MP stability and mobility at low ionic strengths, while high ionic strengths may induce aggregation depending on NOM type and ion valence. Humic substances predominantly increase electrostatic repulsion, whereas proteins and EPS can bridge particles, promoting aggregation. Aging processes, accelerated by NOM photochemical activity, increase surface oxygen functionality and hydrophilicity, further altering transport. The review underscores the need for systematic studies under environmentally relevant conditions to predict MP fate accurately.
Neurotoxicity of Carboxyl-Modified Polystyrene Microplastics on Zebrafish at Early Developmental Stage
Carboxyl-modified polystyrene microplastics (PS-COOH) are negatively charged particles formed by surface oxidation and functional group modification of polystyrene microplastics (PS), widely used in biomedical and analytical chemistry. However, studies on their neurotoxic effects on aquatic organisms are scarce. This study employed zebrafish (Danio rerio) as a model organism, exposing embryos to environmentally relevant concentrations (0.1, 1, 10, 100 μg·L−1) of PS and PS-COOH. Neurotoxic effects were assessed by measuring tail coiling frequency at 24 hpf and swimming velocity under alternating light/dark cycles at 120 hpf. Results demonstrated that both PS and PS-COOH induced neurotoxicity, with PS-COOH significantly reducing tail coiling frequency and average swimming speed compared to PS (P<0.05). Exposure to 10 μg·L−1 PS-COOH disrupted neurotransmitter homeostasis, altering levels of acetylcholine (ACh), serotonin (5-HT), and γ-aminobutyric acid (GABA). Transgenic zebrafish Tg(huc:EGFP) fluorescence assays revealed that PS-COOH (0.1–100 μg·L−1) caused damage to central neurons. These findings indicate that PS-COOH exposure impairs cholinergic, serotonergic, and GABAergic neurotransmission, induces neuronal damage, and exerts neurotoxic effects on zebrafish larvae. This study provides a theoretical basis for assessing the ecological and health risks of modified microplastics.