Publications by authors named "Wennian Xu"

Article Synopsis
  • - This study focuses on assessing soil quality as a key factor for successful vegetation restoration in areas disturbed by engineering activities, utilizing sixteen different soil indicators across six restoration sites.
  • - Researchers identified a minimum and revised minimum data set through principal component analysis and developed six Soil Quality Indices (SQIs) to measure the impact of various restoration methods on soil quality.
  • - Findings revealed that restoration techniques, particularly those at VC and TB sites, significantly improved soil quality, suggesting that the SQI-NLRM method is an effective tool for evaluating soil quality in similar disturbed environments, like the Xiangjiaba hydropower station.
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Article Synopsis
  • Drought stress hampers plant growth, complicating efforts to green slopes, but introducing arbuscular mycorrhizal (AM) fungi can help mitigate these challenges.
  • The study evaluated the impact of AM fungi on two plant species under varying drought conditions, finding that AM fungi significantly improved plant height, root length, and biomass even under drought stress.
  • Results showed that AM fungi boosted photosynthesis, increased protective enzyme activity, reduced oxidative damage, and enhanced overall plant drought tolerance by improving water retention and nutrient uptake.
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  • The study investigates how soil respiration dynamics are affected by different stages of vegetation succession on restored slopes, comparing various vegetation types like herbaceous, shrub, and arborvitae.
  • Soil respiration rates peaked in July and August, showing a decrease as vegetation progressed from herbaceous to arborvitae, with herbaceous stages exhibiting significantly higher respiration rates than arborvitae.
  • Soil respiration was positively correlated with nitrate nitrogen and microbial biomass nitrogen, and the relationship was better explained by a model considering soil temperature and water content, indicating varying soil respiration rates throughout the succession stages.
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Vegetation concrete has been widely applied for the ecological restoration of bare steep slopes in short-term frozen and non-frozen soil regions in China. However, field experiments conducted in seasonally frozen soil regions have revealed decreases in the bulk density, nutrient content and vegetation coverage. This study aimed to clarify the evolution process and mechanism of the engineering properties of vegetation concrete under atmospheric freeze-thaw (F-T) test conditions.

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Background: Soil erosion is a severe problem in the karst watershed, and analysis of soil erosion at the watershed scale is urgently needed.

Methods: This study tried to estimate the soil erodibility factor (-factor) using the Erosion Productivity Impact Calculator (EPIC) nomograph and evaluate the spatial distribution of the predicted -factor in a karst watershed. Soil properties and -factors of five land use types (NF: natural mixed forest, CF: cypress forest, EF: economic forest, ST: stone dike terrace, VF: vegetable land) in the Xialaoxi small watershed were compared and key factors affecting erodibility were analyzed.

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Under freeze-thaw conditions, the substrates used for ecological protection degrade, which involves decreases in compactness and fertiliser retention ability. As such, our purpose in this study was to use two typical types of activated carbon (AC), wood-based activated carbon (WAC) and coal-based activated carbon (CAC), to enhance the antifrost property of vegetation concrete (VC). We investigated the effects of five different proportions of planting soil weight (0.

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Background: To quantitatively evaluate the contribution of plant roots to soil shear strength, the generalized equivalent confining pressure (GECP), which is the difference in confining pressure between the reinforced and un-reinforced soil specimens at the same shear strength, was proposed and considered in terms of the function of plant roots in soil reinforcement.

Methods: In this paper, silt loam soil was selected as the test soil, and the roots of were chosen as the reinforcing material. Different drainage conditions (consolidation drained (CD), consolidation undrained (CU), and unconsolidated undrained (UU)) were used to analyse the influences of different root distribution patterns (horizontal root (HR), vertical root (VR), and complex root (CR)) and root contents (0.

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Vegetation concrete is one of the most widely used substrates for slope ecological protection in China. However, there are still some imperfections that are disadvantageous for plant growth, such as high density, low porosity, insufficient nutrient retention ability and so on. In this paper, the effect of wood activated carbon and mineral activated carbon on the physicochemical properties of vegetation concrete is studied.

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The overland flow erosion is common and became more serious because of the climate warming inducing more runoff in the Tibet Plateau. The purposes of this study were to evaluate the effects of flow rate, slope gradient, shear stress, stream power, unit stream power and unit energy of water-carrying section on the soil detachment capacity for the soil in the Tibet Plateau of China due to the information is limited. To achieve this aim, laboratory experiments were performed under six flow rates (5, 10, 15, 20, 25 and 30 L min) and six slope gradients (8.

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In order to understand the characteristics of the distribution of sediment total phosphorus (TP) and phosphorus fractions in the mainstream sediments in the Three Gorges Reservoir (TGR) after impounding the water level to 175 m, 13 surface sediment samples were collected from the Wujiang to Maoping sections in October 2010. The physico-chemical properties, including organic matter content, particle grain size distribution, and major mineral analysis, as well as total phosphorus and its fractions in the sediment, were determined. Moreover, the relationships among phosphorus fractions, organic matter contents, and particle grain size were discussed, and the effect of the impoundment on sediment phosphorus accumulation and bioavailability was also evaluated.

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Large-scale railway construction has resulted in large areas of bare-cut-slope, and outside soil spray seeding (OSSS), a frequently used technique, has been adopted for slope restoration for many years. However, compared with natural slope soils, the quality of artificial soils on rock-cut slopes is low. Enzyme activity and microbial biomass are the main indices used for estimating soil quality; thus, our objective was to explore the influence of slope position, slope aspect, and season on two important factors that positively influence the plant growth capability in artificial soil.

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Salix variegate, a widely distributed species along the riverbank in Three Gorges Reservoir area, plays an important role in soil conservation and riverbank stabilization. Waterlogging from April to May was simulated in 2006 to test the adapting ability and mechanism of S. variegate seedlings to water environment change resulted from the construction of Three Gorges Project.

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