Slope Ecological Restoration Research Articles

Growth and metabolic differences in the potential of phytoremediation between two hybrid bermudagrasses in roots, stems, and leaves under cadmium stress

Bermudagrass (Cynodon) species has been identified as a dominant plant species in cadmium (Cd)-contaminated soils. Objectives of current study were to evaluate Cd tolerance of two hybrid bermudagrass (Cynodon transvaalensis × Cynodon dactylon) cultivars Tifdwarf and Chuannong-3 for urban greening and slope ecological restoration and further to explore the difference in Cd tolerance associated with changes in ion absorption and distribution, antioxidant metabolism, and accumulations of phytochelatins (PCs) and metallothioneins (MTs) in roots, stems, and leaves. After exposure to equal concentration and duration of Cd stress, growth, chlorophyll content, and photochemical efficiency of both cultivars reduced significantly, but Cd-induced these inhibitory effects were more pronounced in Chuannong-3. As compared to Chuannong-3, Tifdwarf maintained significantly higher Cd concentration in roots and lower Cd concentration, bioconcentration factor, and translocation factor in aboveground parts in response to Cd stress. Each plant of Tifdwarf also accumulated more Cd in leaves, stems, and roots than each plant of Chuannong-3 due to larger biomass under Cd stress. Cd stress also significantly inhibited uptake and partitioning of iron, sodium, and potassium in two cultivars. In addition, Tifdwarf exhibited better antioxidant defense for reactive oxygen species (ROS) scavenging than Chuannong-3 under Cd stress, as reflected by higher antioxidant enzyme activities and antioxidant metabolites involved in ascorbic acid (ASA)-glutathione (GSH) cycle. Tifdwarf also accumulated more PCs in leaves, stems, and roots and more MTs in leaves and stems than Chuannong-3, which could help to chelate Cd to reduce cytotoxicity of Cd. Moreover, strong antioxidant property of MTs was beneficial for maintaining ROS homeostasis in plants. Therefore, better Cd tolerance of Tifdwarf could be mainly due to the inhibition of Cd uptake and partitioning, enhanced ASA-GSH cycle, and more accumulations of PCs and MTs. Tifdwarf showed better potential for Cd remediation or urban greening in Cd-polluted soils.

Analysis on the Impact of Various Slope Ecological Restoration Techniques on Soil Fertility and Physicochemical Properties During the Summer Drought Period in Red Soil Area of Northeast Jiangxi Province

[Purpose] This study aims to investigate the impacts of three slope restoration techniques, namely, soil spray sowing, vegetation fiber, and vegetation concrete, on soil fertility, pH, and organic matter content during the summer drought period. The study also aims to explore the advantages of these three different restoration techniques, providing a basis for slope restoration in the Northeast Jiangxi region. [Methods] The study used experimental slopes established with three different restoration techniques: soil spray sowing, vegetation fiber, and vegetation concrete. Soil samples were collected during the rainy season in July 2022 and the drought season in September 2022. The changes in hydrolyzable nitrogen, available potassium, available phosphorus content, pH, and organic matter in the soil after restoration were comprehensively investigated. The study relies on the Qi-Wu expressway, and all the experiments are set on the slopes on both sides of the expressway. [Results]①For the soil restored using soil spray sowing during the drought season, the content of hydrolyzable nitrogen and available potassium was higher than that of the original soil, while the content of available phosphorus significantly decreased. The pH changed from acidic to weakly alkaline. ②For the soil restored using vegetation fiber during the drought season, although the content of available phosphorus increased, it was still relatively low. The content of available potassium decreased, but the total amount remained high. The content of hydrolyzable nitrogen was high and showed an increasing trend. The pH slightly decreased from weakly acidic to acidic. ③For the soil restored using vegetation concrete during the drought season, the content of hydrolyzable nitrogen, available potassium, and available phosphorus was high and showed an increasing trend. The pH slightly decreased, but it remained weakly alkaline before and after the drought. [Conclusion] Soil spray sowing, vegetation fiber, and vegetation concrete, all three restoration techniques, could demonstrate good performance during the drought period in the Northeastern Jiangxi region. In terms of their overall performance, the ranking from strong to weak is as follows: vegetation concrete > vegetation fiber > soil spray sowing. Soil spray sowing, as the most convenient and cost-effective slope restoration technique, could in the future incorporate additives that can improve local soil properties according to different regional characteristics. Vegetation fiber not only needs to improve soil acidity-alkalinity but should also appropriately incorporate phosphorus-containing additives. Vegetation concrete needs to address the issue of reducing soil acidity-alkalinity after restoration in the future.

Application of Biological Glue-Clay Composite Substrate in Slope Ecological Restoration.

Given the issues of soil cracking, poor water retention during drought, and erosion damage caused by rainfall, we conducted an in-depth study on the water retention properties, cracking resistance, and scouring resistance of biogel-amended clay using evaporation cracking and scouring tests. The hydrophysical properties and cohesive aggregation mechanism of biogel-amended clay were explored, and the results showed that the incorporation of biogel improved the water retention, cracking resistance, and scour resistance of the clay samples. With an increase in the biogel content, the biogel mucous membrane inside the samples improved the cohesion between soil particles, reduced the generation and development of cracks, and improved the cracking resistance. There was no significant cracking of the samples after the biogel content reached 0.3%, which changed the migration of water in the sample, prevented water evaporation, and improved the water retention of the clay samples. Biofilm can change the migration of water in the sample, prevent some evaporation, and reduce the evaporation rate. To a certain extent, it can enhance the water retention capacity of the sample. Enhanced biofilm content significantly reduced scouring in the process of rainfall and runoff erosion of the sample, and biofilm content of 0.2% significantly reduced the surface of the specimen damaged by erosion. The hydrophysical properties of the composite-adhesive-amended clay samples were significantly improved compared with those of the single-bioadhesive-amended clay samples.

Dynamic evaluation on slope ecological restoration effect based on cosine similarity and markov chain

It is important to evaluate the slope ecological restoration effect for diagnosing the slope restoration state in time. Several soft computing methods require experts to determine the index weight, which will affect the rationality of the evaluation results. Moreover, they are all static evaluation methods and cannot reflect the time effect of restoration. Therefore, a dynamic evaluation method has been proposed without determining the index weight based on Cosine Similarity and Markov Chain. Several cases were applied to prove the effectiveness of the proposed method. The results presented that the results of this method are more consistent with the actual situations and can reflect the variability of the restoration effect. Finally, the sensitivity of indexes under different ecological restoration methods was analyzed. The results show that the core link of the restoration method was consistent with the sensitivity result. The proposed method provides a basis for optimizing the restoration methods.

Effects of biochar additions on the mechanical stability of soil aggregates and their role in the dynamic renewal of aggregates in slope ecological restoration

Mechanical stability of soil aggregates is important for resisting external disturbances in slope soils. Biochar (BC) is widely used in slope remediation. However, biochar application may not be conducive to the formation of mechanical-stable soil aggregates, and the effects of biochar additions on the mechanical stability of soil aggregates in slope restoration remain largely unclear. In this context, an incubation experiment was conducted in this study with four biochar levels added to artificial soil, namely 0 % (BC0), 1.5 % (BC1), 3 % (BC2), and 4.5 % (BC3), corresponding approximately to 0, 0.77, 1.53 and 2.30 M ha−1, respectively. The contributions of different soil aggregate fractions to maintaining the mechanical stability of aggregates, as well as the main influencing factors and pathways of biochar additions on soil aggregate stability in a dynamic renewal process of aggregates, were investigated in this study. The results showed a decreasing trend in the mean weight diameter (MWD) with increasing biochar levels and BC1 has no significant difference with BC0, showing MWD values of 2.74 and 2.75, respectively. In contrast, BC3 is significantly lower MWD value of 2.18. The BC3 exhibited negative impact on the mechanical stability of the aggregates. Redundancy analysis (RDA) showed that large macroaggregates (>5 mm) exhibited a stronger contribution on the aggregate mechanical stability between all soil aggregate fractions. The random forest (RF) algorithm and structural equation modeling (SEM) indicated that microaggregate-associated soil organic carbon (SOC) contents and soil pH values were the main factors driving the changes in the aggregate mechanical stability caused by biochar applications. Indeed, the biochar level of 1.5 % maintained the stability of macroaggregates and increased the microaggregate-associated SOC content by 35.7 %, which was conducive to the formation of microaggregates within macroaggregates. Our study suggests that the application of biochar at a level of 1.5 % is more beneficial for maintaining the mechanical stability of artificial soil aggregates.

A State-of-the-Art Review of Organic Polymer Modifiers for Slope Eco-Engineering.

In slope ecological restoration projects, reinforcing soil and promoting vegetation growth are essential measures. Guest soil spraying technology can be used to backfill modified soil and vegetation seeds onto the slope surface, resulting in successful ecological restoration. The use of organic polymer modifiers to reinforce soil has several benefits, such as high strength, effective results, and low pollution levels. Organic polymer soil modifiers can be divided into two categories: synthetic polymer modifiers and biopolymer modifiers. This paper provides a thorough review of the properties and interaction mechanisms of two types of polymer modifiers in soil consolidation. The properties of organic polymer modifiers make them applicable in soil and vegetation engineering on slopes. These modifiers can enhance soil mechanics, infiltration, and erosion resistance and promote vegetation growth. Therefore, the suitability of organic polymer modifiers for soil and vegetation engineering on slopes is demonstrated by their properties and potential for improvement in key areas. Furthermore, challenges and future prospects for slope protection technology using organic polymer modifiers are suggested.

Vegetative substrate configuration technology for tower foundation slope of transmission line in arid area considering species suitability

AbstractIn order to realize the ecological restoration of transmission line tower foundation slope and enrich the research methods of slope ecological restoration, this paper studies a nutrient matrix configuration technology for transmission line tower foundation slope in arid areas. The Xilingol arid grassland area in Inner Mongolia is selected as the research object, and plants such as Leymus chinensis, Festuca arundinacea and Agropyron pratense are selected as the grass species of the vegetative substrate configuration technology. Different proportions of water retaining agent, compound fertilizer, microbial agents and other substances are added to the soil, which are combined into 10 test groups. The effect of slope ecological restoration is verified by species suitability, physical and chemical properties of matrix and plant growth. The resβults showed that Caragana korshinskii, Artemisia annua, Astragalus adsurgens, Sonchus oleraceus and other plants are the dominant grass species in the plant substrate plants; The physical and chemical indexes of soil's bulk density, organic matter, total nitrogen and so on in group B2 are better than those in other groups. Adopting the vegetative substrate configuration technology with the proportion of group B2 can obtain a good ecological restoration effect of tower foundation slope of transmission line in arid areas. The vegetative substrate configuration technology can solve the long‐standing ecological and environmental protection problems of the tower foundation slope of transmission line in arid areas, and should be actively promoted and applied. Daur lymphatic is also widely used in ecological restoration of transmission line base slope in arid region. The average coverage rate was 14.85%. The average height was 100.5 cm. It could grow at an altitude of more than 1000 m. After the nutrient matrix of the transmission line base slope was configured, the grass planting belt was established under normal maintenance, and the seeds began to germinate 3 days later. After 10 days, the germination rate was 78% and the coverage rate was 65%.

Experimental Study on Ecological Performance Improvement of Sprayed Planting Concrete Based on the Addition of Polymer Composite Material.

Sprayed planting concrete (SPC) can be used for the ecological restoration of rocky steep slopes. It is a kind of outside-soil material with excellent soil and slope stabilization performance, and plants can grow in SPC, thus achieving harmony between engineering stability and ecological restoration and improving the landscape and ecosystem. The addition of cement is the key to allowing SPC to achieve slope stabilization and prevent soil erosion. However, the addition of cement can cause SPC to have high alkalinity, overheating (cement generates hydration heat), and excessive hardening, which are not conducive to the growth of plants and can lead to poor ecological performance of SPC for slope ecological restoration. We studied the improvement of the ecological performance of SPC by using a polymer composite material composed of a polymer adhesive material and a polymer water-retaining material. This paper studied the improvement effects of the polymer composite material on the ecological performance of SPC used in slope ecological restoration through a laboratory erosion resistance test and a plant growth test. The results showed that SPC with the addition of polymer composite material can reduce its cement content by about 50% while still retaining excellent erosion resistance performance when it is used in slope ecological restoration. Additionally, the plant germination rates and plant heights when using the SPC improved by polymer composite material were increased by 190% and 110%, respectively. These results show that polymer composite material can significantly improve the ecological performance of SPC and effectively improve its slope ecological restoration effects. This study provides theoretical and technical support for the application of SPC in ecological restoration on rocky steep slopes.

Polyvinyl acetate-based soil stabilization for rock slope ecological restoration

External-soil spray seeding (ESSS) is a method often used for the ecological restoration of bare rock slopes. However, the direct use of ESSS is normally less satisfactory due to the erosion of sprayed soil and low survival rate of the plants on rock slopes. This study proposes a novel approach to addressing this issue through the combined use of ESSS with polyvinyl acetate (PVA) based soil stabilization. The PVA solutions are added to the soil to stabilize soil and improve soil strength while possessing high water and nutrient retention favorable for plant growth. A series of experimental tests on the mechanical properties, water stability, erosion resistance, water retention, and plant growth of the PVA-stabilized soil were conducted to assess the efficacy of the proposed method. The results showed that the proposed method could be promising for rock slope ecological restoration. A proper curing time (e.g., >3 days) was required to achieve beneficial effects of PVA on the soil properties. A shorter curing time would otherwise result in the decrease in the strength with the increased PVA content. It was found that the optimum PVA content was 3% for achieving the maximum water stability, erosion resistance, water retention, and plant growth. The cohesion increased by up to 50% and the internal friction angle increased by 3.5° compared to the natural soil. The disintegration rate of the stabilized soil was generally < 3e-3%/min. The maximum reduction in erosion was up to 83% when the PVA content ≥3%. The mechanisms behind the findings are also discussed.

Effects of Municipal Solid Waste on Planting Properties and Scouring Resistance of Vegetation Concrete (Wuhan, China).

Vegetation concrete (VC) laid as a reinforcement base and covered by a soil layer with vegetation has been increasingly used to beautify the landscape, reduce environmental pollution and control stormwater runoff. In this study, the effects of municipal solid waste (MSW) on vegetation characteristics of modified VC were tested under different mix compositions. We first explored the effects of the mixed concrete environment on Festuca elata and perennial Ryegrass for 60 days. Then, the influence of various MSW contents added to different percentages of cement on scouring resistance of VC was examined. The experimental results revealed that the germination rates and plant heights of both species decreased with the increase in concrete content. Considering the scouring resistances, the optimal mix proportion of MSW-modified VC was recommended as No. 25, with 5% KW fertilizer, 8% cement and 0.5% wheat straw in this study. Furthermore, adding a small amount of fallen leaves or silica fume to VC can promote the growth of both species to some extent, although these additions had an inverse effect on the scouring resistances. The results contribute to beneficial knowledge for future research on the feasibility of the use these species with VC technology for slope ecological restoration.

Optimal Allocation of Slope Ecological Restoration for the Climate Change Mitigation and Natural Function Improvement

The key to dealing with extreme problems at watershed or region scales in the context of climate change is the “de-extremalization” of hydrological processes. The foundation lies in how to optimize the allocation of ecological restoration on slopes to mitigate the extreme impacts of climate change on hydrological processes and improve ecological service functions. Previous studies focused on analyzing the direct effects of slope land use, vegetation distribution, or historical pattern of ecological restoration on runoff processes. This study developed a slope ecological restoration evaluation system to evaluate the naturalness, functional types, and functional coordination of slope ecological restoration at different historical stages and quantitatively identified the mitigation effect on climate change in the future, which was applied to the Huangshui River Basin (above Minhe County) in Qinghai Province, China. Based on the land suitability evaluation methods, a set of layout schemes were constructed. The runoff mutation and ecological function of different schemes under climate change were evaluated, and the highly suitable scheme was selected as the optimal scheme. Compared with the current situation, the coupling coordination degree index of the scheme would increase from 0.32 to 0.59. Meanwhile, the runoff and coefficient of variation would decrease by 30% and 60%, respectively, during the wet season under the high-emission scenario RCP8.5. This study closely links the ecological construction of slopes with the response to extreme climates, which provides technical methods and practical support for the optimization of regional ecological patterns and scientific water governance modes.

Retraction Note to: Slope ecological restoration based on image classification and construction of sports fitness index

This study uses literature method, comparative research method, qualitative and quantitative multiple demonstration method, Delphi method, analytic hierarchy process and survey method, image classification, mathematical statistics based on local characteristics and international experience, and other research methods to explore the construction of national and international children and youth sports fitness evaluation index system. In the process of construction, it is the first to establish the development history of Chinese children and adolescents’ physical quality assessment. Secondly, following the specific program design, we use and optimize the child and adolescent grade index system and verify the child and adolescent physical condition grade model. Finally, the paper puts forward the suggestion of sustainable utilization evaluation index system to promote the health of children and young people. This paper also studies the exposed slopes produced by a large number of slope engineering in the process of highway construction. It has the problems of weak soil structure and insufficient plant coverage. The slope problem of highway laterite in rainy area A is particularly serious. It is very important to adopt necessary slope ecological restoration for slope safety and stability, soil and water conservation, and plant community reconstruction. According to the disease characteristics of red clay slope in a rainy area, this paper analyzes the ecological principle and plant quarantine mechanism of slope ecological restoration, takes into account the two main characteristics of poor erosion resistance of slope, and introduces three new functional materials: red clay and low slope, nutrient content of slope, and artificial soil and soil stabilizer for erosion control. It promotes the further research on ecological restoration technology of red clay slope.

RETRACTED ARTICLE: Slope ecological restoration based on image classification and construction of sports fitness index

RETRACTED ARTICLE: Slope ecological restoration based on image classification and construction of sports fitness index

Discussion on Ecological Protection Technology of High and Steep Slope of Expressway

The construction and development of expressways have played a positive role in promoting regional economic and social development, but the construction process and behaviour have caused disturbance to the original landform and caused various damages to the slope. It is currently reasonable protection of the slope is one of the important works of highway construction. This article takes the Huizhou-Qingyuan section of the Shan-Zhan Expressway as an example, analyses and studies different slope ecology from the three aspects of the slope ecological protection mechanism, the slope ecological protection difficulties and the slope ecological restoration design, combined with the current situation of the slope along the line and the main restoration difficulties. This article studies the principles, forms, characteristics of protection technology, and the design of typical slope ecological restoration. The results show that reasonable ecological protection of slopes according to local conditions can achieve slope protection, prevent soil erosion, restore and improve the local ecological environment, and improve highways. The integration and coordination of road landscape and natural landscape are of great significance to ecological environmental protection and driving safety.

Optimal Allocation Model of Plant Community in Slope Ecological Restoration

&lt;p&gt;In order to effectively analyze the optimal allocation mode of plant community in the process of slope ecological restoration, 15 plants were selected and 10 plant community combinations were designed. The experiment lasted for 90 days, and the optimal allocation model of plant community was obtained. The optimal allocation pattern of plant communities in slope ecological restoration was C7: 10 plants of Amorpha fruticosa + 20 plants of Vitex negundo + 30 plants of Festuca arundinacea + 20 plants of Moxa argyi + 10 plants of Dianthus caryophylla + 20 plants of Lespedeza + 10 plants of Leucaena + 8 plants of Acacia; C8: 30 plants of Euonymus microphylla + 10 plants of Shearnut + 20 plants of Alfalfa + 30 plants of Pigeon Beans + 20 plants of Crotalaria mucronata + 20 plants of Mimosa bimucronata; C3: 20 plants of Amorpha fruticosa + 50 plants of Euonymus fortunei var. radicans + 20 plants of Aicao + 10 plants of Pigeon bean + 8 plants of Leucaena +10 plants of Dodonaea viscosa. The experimental results show that the optimal allocation model of plant community is effective in slope ecological restoration.&lt;/p&gt;&#x0D;

The Future Prospects of Arbuscular Mycorrhizal Fungi in Slope Ecological Restoration

The Future Prospects of Arbuscular Mycorrhizal Fungi in Slope Ecological Restoration

Three-dimensional geonet ecological slope protection technology and its engineering application

A protective structure system for slope with combination of vegetation and 3D geonet network was established. First the mechanism and ecological effects of slope protection with vegetation technology in slope engineering were discussed. Then specific implementation steps were proposed. Taking a slope ecological restoration project as an example, herbaceous plants suitable for slope protection were compared and tested, long term monitoring shows that the slope plants grow well, the protection effect of the new branches and roots were obvious, the stability of the slope was enhanced under comprehensive protection measures.

Research on the ecological restoration method for highway debris slope: A case study of Guidu Highway in China

To clarify the superiority of slope ecological restoration technology in slope restoration, the artificial slope in the section of Guiyang-Duyun highway as the case study was analyzed in this paper. Plant sample collection experiments were carried out by sample method, and the evaluation indicators factors were plant distribution density, biomass and soil nutrients. The effect of slope restoration was evaluated by comparing with the ecological effect of traditional slope restoration measures. The results showed that for the slope ecological restoration sample, the average cumulative plant density was 187 plants per square meter, about 3.8 times of the comparison sample. The average biomass was 333.25g/m2 , which was about 6.4 times that of the comparison sample. Soil nutrients were also much higher than those in the comparison sample. The ecological restoration of the slope with ProGanics and Flexterra materials was superior to the traditional slope restoration measures. The oretical research results will have important theoretical and technical significance for the ecological restoration method for highway debris slope of Guidu highway.

Study on the selection of vegetation for ecological restoration of residual soil slopes in South China

Vegetation selection is one of the key contents of slope ecological restoration, based on the characteristics of climate and soil in South China and the principle of local conditions, this paper studies the selection of vegetation in the ecological restoration project of the residual soil slope. The typical herbs, shrubs and trees suitable for the area are determined by theoretical analysis. At the same time, through field tests, the growth and development of vegetation after the spraying are monitored for a long time, and the interaction relationship between vegetation community after multiple vegetation mix-ups is analyzed. The results show that plant selection should avoid the choice of a single plant, and should try to achieve complementary coordination between species. At the same time, when taking a variety of plant mixing spray, the configuration ratio of different plants should be determined according to the growth cycle of different plants and the results of indoor ratio test, so as to avoid mutual interference.

Effects of Slope Ecological Restoration on Runoff and Its Response to Climate Change.

Slope ecological restoration and climate change are important factors affecting the hydrological processes of the Huangshui River Basin in Qinghai province, China. How to quantitatively identify the impact of slope ecological restoration on runoff and whether slope ecological restoration can mitigate the impact of future climate change on runoff are both very important. In this paper, the Huangshui River above the center of Minhe county was taken as the research area, and the Pinus tabulaeformis and shrubs were taken as the main forest land types of slope ecological restoration. First, based on the law of forest land variation, the construction scales of slope ecological restoration in different periods were identified. The influence of slope ecological restoration on runoff was then quantitatively evaluated by using a distributed hydrological model. Second, the future climate scenarios of five general circulation models (GCMs) under three representative concentration pathways (RCPs) (i.e., RCP2.6, RCP4.5, and RCP8.5) from 2021 to 2050 were selected and modified by model integration. Combined with the slope ecological restoration scenarios, the influence of slope ecological restoration on runoff under future climate scenarios was explored. The results showed that the effect of slope ecological restoration was significant. Compared with 1980, the area of slope ecological restoration increased by 24% in 2017. Under the present climate conditions (1960–2017), different periods of slope ecological restoration have an effect on the process of runoff in the wet season (June, July, August, and September) and dry season (January, February, March, and December), which eliminates the maximum, replenishes the minimum, and reduces the variability of runoff processes in the watershed. Under the future climate scenario (2021–50), slope ecological restoration will reduce runoff. On the other hand, climate change will increase runoff, and the combination of the two effects will have a certain offsetting effect. On the whole, comparing the influence of slope ecological restoration on the runoff process with that of climate change in different seasons, due to the main influence of slope ecological restoration, the runoff decreased by about 55% in the temperate season (April, May, October, and November), and increased by about 50% in the dry season or wet season due to the main influence of future climate scenarios.