Soil Restoration Research Articles

Effects of Inoculating Symbiotic Microorganisms on Acacia mangium Grown on Coconut Fiber

The ability of Acacia mangium to grow on degraded soils, thanks to its ability to fix atmospheric nitrogen, makes it a very important species in agroforestry and in the restoration of impoverished soils. However, all the experiments on Acacia mangium, whether inoculated or not, have only been carried out on a single type of substrate, i.e. soil. The aim was to determine whether inoculation significantly increased the biomass and height growth of Acacia mangium grown on coconut fiber. The experimental design comprised 5 treatments (Ta, T, M, R, and MR) with 5 replicates. Characterizing the coconut fiber and the dry biomass of Acacia mangium above ground and roots consisted of determining the content of elements such as P, K, Ca, Mg, and N. The number of nodules was also counted The results showed that inoculation (M, R and, MR) had no significant effect on the height growth and biomass of Acacia mangium. Non-inoculated (Ta and T) plants showed greater growth, probably due to the richness of nutrients (N, P) in the coconut fiber. The presence of nodules in the non-inoculated plants indicates the presence of indigenous strains in the coconut fiber. Double inoculation (mycorrhizae/rhizobia) significantly stimulated the growth and nodulation of Acacia mangium. Double inoculation also increased substrate fertility, which had a positive effect on plant growth. The Glomus-Bradyrhizobium combination appeared to be the most effective in improving the growth and nodulation of Acacia mangium.

Exploring the growth and phytoremediation efficacy of Suaeda fruticosa in agricultural soil contaminated by shrimp aquaculture

Plants face numerous environmental challenges from biotic and abiotic stressors, with soil salinization emerging as a significant global concern. The coastal regions of Tamil Nadu, face severe environmental challenges due to discharge of saline water from shrimp farms exacerbates this issue, compromising the viability of paddy and other crops in the vicinity. This study explores the phytoremediation potential of Suaeda fruticosa in addressing soil salinity resulting from shrimp farming activities under field conditions over a 120-day period to restore soil health in salt affected soil. This research demonstrates Suaeda fruticosa’s exceptional salt tolerance and bioaccumulation potential in facilitating soil restoration. Significant enhancements were observed in various growth parameters, including 466% increase in plant height, 338% in fresh weight and 387% in dry weight. Biochemical parameters also showed substantial enhancements with total chlorophyll, protein, proline, phenol, and glycinebetaine levels increasing by 655%, 588%, 690%, 153%, and 531%, respectively. Enzymatic activities exhibited notable elevations as well, with catalase, peroxidase, and polyphenol oxidase activities escalating by 258%, 587%, and 121% respectively, indicating robust adaptation to saline environments. Moreover, Suaeda fruticosa exhibited remarkable bioaccumulation capabilities, accumulating 461 kg NaCl ha−1. This led to substantial improvements in soil characteristics, including a reduction in pH from 8.8 to 6.49, electrical conductivity from 5.7 to 1.53 dSm−1, and sodium adsorption ratio from 16.1 to 4.4 mmol L−1. The successive cultivation of Suaeda fruticosa in this study, has proven to be a viable strategy for reclaiming salt-affected lands, thereby alleviating a significant constraint on crop productivity.

COMPARATIVE EVALUATION OF SORBENTS BASED ON NATURAL MATERIALS FOR CLEANING OIL-POLLUTED SOILS IN THE KOLA NORTH

The article presents the results of using sorbents based on natural materials as soil reclamation agents in the Arctic zone of the Russian Federation to reduce the negative impact of oil and oil product spills. It has been established that the most effective are composite sorbents based on sphagnum moss and peat in various combinations with excess activated sludge. The effectiveness of sorbents based on natural materials is compared with the commercial sorbent OilSorb. High dynamics of reducing the content of oil products in the first days in soil samples with the addition of composite sorbents, including natural sorption material and activated sludge, is noted.

Changes in Soil Physicochemical Properties and Fungal Communities Following a Forest Fire in the Pine Forest of Uljin, Republic of Korea

Soil samples from the rhizosphere of pine (Pinus densiflora) stands in the fire-disturbed Uljin forest were collected to analyze their physicochemical properties and fungal communities. In the burned area, soil pH decreased by 0.56, and organic matter content decreased by 0.32%p compared to the undisturbed area. Fungal community analysis revealed that all alpha diversity indices decreased in the burned area, but there were no differences according to fire severity. Soil pH, available phosphorus, and total nitrogen showed a positive correlation with the alpha diversity. Additionally, beta diversity analysis also indicated significant differences in the fungal communities between the burned area and the control sites (p value = 0.031). The changes in fungal communities were considered to be influenced by the decline in the order Atheliales, genus Russula, and genus Trechispora. A prediction analysis of the functional traits of fungi showed that the number of fungi involved in nutrient absorption and decomposition decreased in the burned area. It seems that the soil restoration of pine forests is progressing very slowly, as the soil fungi related to nutrient absorption by pine trees have not recovered even 18 months after the forest fire. Therefore, it is necessary to monitor continuous fungal communities in pine forest restoration after a forest fire to determine forest ecosystem restoration success and stabilization.

The Role of Organic Amendments and Their Impact on Soil Restoration: A Review

Soil organic matter (SOM) plays a pivotal role in maintaining soil health by enhancing its physical, chemical, and biological properties. It improves soil structure, water retention, nutrient availability, and microbial activity, contributing significantly to sustainable agriculture. Organic amendments, including animal manure, compost, biosolids, crop residues, and various organic by-products, are widely used to restore degraded soils by increasing SOM content. These amendments not only supply essential nutrients but also promote biological aggregation, suppress soil-borne pathogens, and improve soil's resistance to environmental stressors such as drought and heavy metal toxicity. The positive impacts of organic amendments on soil properties are well-documented, with key benefits including increased soil organic carbon (SOC), improved nutrient cycling, enhanced microbial diversity, and greater water-holding capacity. Organic materials such as compost and animal manure have been shown to significantly improve soil fertility and restore degraded soils. The application of green manure and crop residues also boosts soil biodiversity, enhances rhizospheric processes, and supports overall ecosystem resilience. This paper emphasizes the importance of adopting holistic soil management practices that include organic amendments, conservation tillage, and sustainable cropping systems to address soil degradation. By focusing on replenishing SOM, improving nutrient availability, and increasing soil biodiversity, these practices can contribute to the long-term sustainability of agricultural systems and environmental health. The restoration of soil organic matter is essential for enhancing soil quality and mitigating degradation, ultimately ensuring food security and ecosystem stability for future generations.

Optimization of Acacia auriculiformis A. Cunn. Ex Benth. Seed Germination Using Pretreatment Analysis

Agroforestry resources play a crucial role in conserving biodiversity, stabilizing soils and improving the livelihoods of rural populations. This study investigates the impact of different treatments on the germination of Acacia auriculiformis, an important tree species for soil restoration in Côte d'Ivoire. The work was carried out at the University Jean Lorougnon GUEDE in Daloa. The seeds used for this work were subjected to four treatments, including a control (T0); those soaked for 3 days in ordinary water (T1); a hot water treatment at 60°C (T3); a boiling water treatment at 100°C and a flame treatment (T4). A randomized block design consisting of four treatments in three blocks. The results showed that seed treatment in hot water at 100°C until cooling gave the best germination percentages and germination speed. The results also showed that soaking the seeds in water for three days produced seedlings with the shortest germination time. The study underlines the importance of pregermination for the selection of better-performing varieties and the implementation of effective reforestation programs. It also highlights the need for further research into the impacts of climate change on tree germination and growth. However, for a better policy of extension, production and improvement of this endangered forest species of socio-economic interest, mastery of the requirements of this species while maintaining optimal conditions for its germination in the nursery is more necessary.

Combined Application of Biochar and Calcium Superphosphate Can Effectively Immobilize Cadmium and Reduce Its Uptake by Cabbage

Biochar and phosphate fertilizer are commonly employed for the mitigation of soil cadmium (Cd) contamination. Nevertheless, there is a dearth of research regarding the mechanism behind their joint implementation. In this study, a combination of corn straw biochar (0 (C0), 5 (C5), and 10 (C10) g kg−1) and calcium superphosphate (0 (P0), 0.1 (P1), 0.2 (P2), 0.5 (P5), and 1.0 (P10) g kg−1) was applied in pot experiments, and the effects of the combined application on Cd bioavailability and its uptake by cabbage were investigated in Cd-contaminated soils. The results demonstrated that the combined treatment of applying biochar and Ca(H2PO2)2 yielded a significant decrease in the uptake of Cd by cabbage in alkaline soil, in contrast to the individual treatments of biochar or Ca(H2PO2)2. Compared to the CK treatment (C0P0), the Cd content in the shoots decreased by 46.26% and in the roots decreased by 24.81%, while the biomass of the cabbage demonstrated a noteworthy increase in C5P10 treatment. Compared to the CK treatment, the content of available phosphate (AP) in the soil increased by 17.57 mg kg−1, residual Cd increased by 22.02%, the exchangeable Cd decreased by 45.86%, and carbonate-bound Cd decreased by 20.55% in the C5P10 treatment. Therefore, it is advisable to use a combination of 5 g kg−1 biochar and 1 g kg−1 Ca(H2PO2)2 for the restoration of soil contaminated with Cd.

Evaluation of the Ability of Ameliorants to Influence the Biological Indicators and Hydrophobicity of Oil-Contaminated Haplic Chernozems

ABSTRACT The aim of the study was to assess the ameliorants effect on the biological parameters and Haplic Chernozems hydrophobicity. In model experiment conditions, Haplic Chernozem was polluted by oil and remediation with application of nitroammophos, Sodium humate, biochar, and Baikal EM-1 was simulated during to 30, 90, and 180 days. Indicators of soils activity – germination and intensity indicators of initial seed growth, the activity of catalase and dehydrogenases, the total number of bacteria, hydrophobicity were studied. On the 30 and 90th days after remediation, the most significant reliable decrease in oil regarding was promoted by 2 D biochar. After 180 days of dose 1 D and dose 2 D nitroammophos, as well as 1 D Baikal EM-1, the total petroleum hydrocarbon content was reduced significantly. Baikal EM-1 and biochar contributes to the greatest decrease in hydrophobicity at all periods of the experiment to a greater extent. On the 30th day, the introduction of nitroammophos, biochar, and 1 D Sodium humate contributed to an increase in the integral indicator of the biological state of oil-contaminated Haplic Chernozem, on the 90th day, the introduction of all doses of biochar led to an increase in the indicator, and on the 180th – all doses of Baikal EM-1, and 0.5 D Sodium humate. The research results may be used when choosing a method of soil restoration after oil pollution.

An enhanced electrokinetic system for remediation of Cu-polluted clay soils by integrating purging solutions and intermittent power

This study investigated the effectiveness and underlying mechanisms of purging solutions enhanced by intermittent power in improving electrokinetic (EK) restoration of clay soils even under high levels of heavy metals (HM). In so doing, the artificially contaminated specimens containing a wide range of copper (Cu) were prepared and then subjected to a series of EK tests with various electrolytes and electric regimes. Macro and micro scale examinations revealed that under the unenhanced EK condition (i.e., continuous current without agents), the formation of non-conducting solid phases and/or the clogged fabric in the samples with the high dosages (> 250 mg/kg) of HM could dramatically impede the metal separation from the soil. Hence, increasing the remediation time would not be very effective in facilitating the decontamination process. It was observed that the EDTA-ameliorated treatment accompanied by pentetic acid and acetic acid can mitigate the metal precipitation/encapsulation effects induced by EK actions, resulting in improved rate of HM removal. In this case; however, a high portion of these enhancers would be required to ensure the stable mobility of ions and to achieve successful recovery. Such a limitation has been shown to be overcome by incorporating pulsed power (PP) at an optimal frequency. In fact, as evidenced by SEM-EDX and XRD analyses, the integration of chemical agents with PP could simultaneously retain the solubilized Cu species in the soil mass and modify the matrix tortuosity (i.e., the establishment of well-linked pores), two features that have been found to play essential roles in providing for favorable activity of HM ions during the EK operation. The corresponding refinements in the binary system would cause an almost 8 folds increase in the removal efficiency and a shorter (up to 30 %) time of treatment compared to conventional EK.

Restoring Degraded Lands in Maroua I Municipality, Cameroon: Application of Veazcomutech Techniques

This study was carried out in the Sudano-Sahelian zone of Cameroon. It aims to contribute to the restoration of degraded land in the localities of Maroua I; to set up a sustainable soil restoration technique based on Vetiveria zizanioide- Azadirachta indica-eggshell and Musa paradisiaca peel; to evaluate the restoration of this land through the crop set up and to assess the state of the art of the "VEACOMUTECH" technique on an area of 103.5 m2. The method envisaged in this research is based on the new modern technique "VEAZCOMUTECH): Technique of V. zizanioide, A. indica, Musa paradisiaca and eggshell" with a view to restoring the fertility of the land and diversifying the population's sources of income by using this technique. The study was carried out in the Maroua I municipality on experimental plots at the Technical School of Agriculture. A control plot and a main plot treated with VEAZCOMUTECH were selected. The most vigorous species were chosen to measure growth and yield parameters over a three-week period. The results of this study show that the application of "VEAZCOMUTECH" on the site increases plant growth. In the first week, leaf length ranged from six (06) to fifteen (15) centimetres on average in the control plot. In the main plot where "VEAZCOMUTECH" was applied, leaf length ranged from ten (10) to thirty-two (32) centimetres during the same week. By the third week, leaf length had increased from 15 to 20 centimetres, while in the main plot, leaf length had increased from 32 to 80 centimetres. There was also a clear difference in the number of leaves at week three, with 20 and 87 leaves for the control and main plots respectively. The largest number of flower buds (23 flower buds) was observed on the plant in the main plot, compared with 2 flower buds in the control plot. These results could serve as a reference for the strategy of restoration and fertilization of degraded land in the Far North Region in particular and in the Sudano-Sahelian zone in general.

Short‐term survival and growth of 32 native boreal plants on treated oil sands tailings

AbstractThe consolidation of oil sands tailings is a cost‐ and time‐consuming process that requires treatment via active (e.g., centrifugation) and passive (e.g., self‐weight consolidation) methods. The use of plants to dewater tailings is a promising concept and has previously been evaluated using agronomic grass species in greenhouse studies. This greenhouse study evaluated the short‐term survivorship and growth of 32 upland and lowland native plant species (12 forbs, 14 graminoids, and six woody plants) in centrifuged tailings and benchmarked their performance against reclamation soil and undisturbed forest soil. All plant species were propagated from seed and transplanted as seedlings into containers filled with one of the three substrates. After 42 days, the height (woody species only) and total aboveground biomass were determined for all living plants. As expected, the mortality of seedlings in tailings was higher than plants grown in the other two substrates. Graminoid species, regardless of species community type (wetland or upland), had higher survival probabilities and growth compared to forb or woody species across all substrates. Of forbs and woody species evaluated, Geum aleppicum and Populus tremuloides showed the most promise amongst the upland species, and Rumex occidentalis was the wetland equivalent.

Predicting Subsurface Drainage Requirement for Different Soil Desalinization Goals in Coastal Reclamation Areas

ABSTRACTBuilding subsurface drainage systems for more efficient salt leaching with the natural rainfall or artificial irrigation is a widely accepted practice for saline soils reclamation, but the high initial cost of the system construction often limits its adoption, and the uncertainty in drainage intensity requirement to meet desired desalinization goals for field crop production challenges the system design. In this paper, we proposed a soil desalinization model based on the field hydrology model‐DRAINMOD, predicted number of years required to lower soil salinity to a threshold level under different subsurface drainage conditions, and estimated the net return from different subsurface drainage system layout based on a case study in a coastal reclamation area in eastern China. The results showed that, DRAINMOD accurately predicted water table fluctuations in artificially drained fields: the root mean square error to standard deviation ratio (RSR) was 0.4 and 0.54, and the Nash Sutcliffe efficiency (NSE) was 0.84 and 0.68, respectively, during the model calibration and validation periods. The DRAINMOD based soil desalinization model predicted a negative relationship between subsurface drainage intensity and the soil desalinization period, that is, improving drainage condition shortened the time requirement for soil desalinization. For the study area, the model's predictions showed that installing subsurface drainage at 20 m spacing and 1.2 m deep lowered soil salinity to the slightly saline level in less than 7 years under the rainfall leaching only, and such system layout produced the maximum economic return based on the local agricultural practice. The results indicate that, early investment in adequate subsurface drainage systems is beneficial for field crop production in the salt impacted farmland areas. Findings from this research may provide technical references for saline soil reclamation or land improvement in both rain fed and irrigated agricultural areas.

Circular Regenerative Agricultural Practices in Africa: Techniques and Their Potential for Soil Restoration and Sustainable Food Production

The conventional linear system of global food production and consumption is unsustainable as it is responsible for a substantial share of greenhouse gas emissions, biodiversity declines due land use change, agricultural water stress due resource-intensive water consumption patterns and land degradation. During the last decade (1994–2014), for example, the greenhouse emissions from agriculture in Africa were reported to increase at an average annual rate of between 2.9% and 3.1%, equivalent to 0.44 Gt and 0.54 Gt CO2 per annum, respectively. Between 2000 and 2020, the greenhouse gas emissions from agrifood systems were shown to decrease in all major regions of the world, except in Africa and Asia, where they grew by 35 and 20 percent, respectively. With most of the circular agricultural practices still central to food production in the developing African countries, the continent can spearhead a global return to circular agriculture. Using a descriptive review approach, we explore the literature to examine the extent to which African agriculture is deploying these practices, the potential areas for improvement and lessons for the world in embracing sustainable food production. We underscore that the farming communities in sub-Saharan Africa have, for decades, been using some of the most effective circular agricultural principles and practices in agricultural production. We further show that practices and strategies akin to sustainable agricultural production include agronomic practices, smart irrigation options, renewable energy harvesting and waste-to-fertilizer technologies. All of these technologies, which are central to sustainable agricultural production, are not new to Africa, although they may require packaging and advocacy to reach a wider community in sub-Saharan Africa.

Soil reclamation of cranberry plantations on reclaimed lands in Arkhangelsk region

In the production conditions of the "Arkhangelsk cranberry" in the Arkhangelsk region, the land use analysis was carried out as a part of land use monitoring in this agricultural production. In 2015, the first cranberry plantations were planted, and in April 2023 about 40 hectares of peatlands were already in land use of the factory including 8 fields (checks) with an average area of 1 hectare. An assessment of the dynamics of change on the area of the created plantation was carried out for all indicators such as the length of roads, developed area and some separately designed structures (except of drained bogs). It was found that the soil indicators of peatlands are normal for this type of lands, and provide favorable conditions for growing cranberries. The analysis of the dynamics of land use in the period from 2015 to 2023 revealed the following dynamic indicators: an increase in the area of active land use by 418.97%, an increase in the area of drained swamps by 310.68%, 5.5 hectares were withdrawn from the forest fund, 42.31 hectares are under development (complex works), the total number of checks for planting increased by 23 parcels, an increase in the length of roads, including dirt roads, by 8.6 km, an increase in the number of fire ponds by 3 pieces, an increase in the number of sludge ponds by 3 pieces, and, finally, 1 recreational site was commissioned. The research has also shown that drainage does not lead to a significant change in the chemical composition of the organic part of peat and its agrochemical properties, so using drainage is not rational. In this case, a slight change in the water-air regime was observed together with the changes in the soil-forming process, and some activities of microorganisms, which was a prerequisite for an increase in the level of mineralization of the organic part of peat. Despite the gradual commissioning of peatlands, environmental sustainability has a trend towards an increase, which should be taken into account in the further development of the enterprise.

Ecological Utilization of the CO2 Mineralization Using Alkaline Solid Wastes: Synthesis of Porous Materials for Sandy Soil Restoration

Ecological Utilization of the CO₂ Mineralization Using Alkaline Solid Wastes: Synthesis of Porous Materials for Sandy Soil Restoration

Analysis of the structure of Russian acreage within the framework of the concept of sustainable agriculture

The purpose of scientific work is a comprehensive analysis of the impact of changes in the structure of acreage and the land use system on ensuring the sustainability of the agricultural industry in Russia. The results obtained demonstrate that, despite the implementation of a number of legislative initiatives aimed at improving the efficiency and environmental orientation of agriculture, a number of unresolved problems remain in the Russian Federation that hinder the transition to a model of sustainable agricultural production. Inefficient use of land resources is a problem faced by many agricultural regions in Russia. Irrational structuring of land, unbalanced distribution of agricultural land, low efficiency of use of modern technologies and resources lead to the loss of land potential. This has a negative impact on the yield and quality of agricultural products. There may be insufficient attention to the environmental aspects of land management: conserving biodiversity, maintaining natural ecosystems, minimizing the ecological footprint of agricultural activities and applying methods that promote soil regeneration. The comprehensive improvement of land management mechanisms in the Russian Federation, taking into account the concept of sustainable agriculture, involves the development and implementation of policies aimed at stimulating sustainable agricultural practices, supporting innovative methods and technologies, as well as training and advising agricultural producers on sustainable agriculture. This approach will significantly improve land use efficiency and ensure the sustainable development of Russia's agricultural sector.

Investigation of the impact of dual inoculations of arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria on drought tolerance of maize grown in a compost-amended field under Mediterranean conditions.

In the current context of rapid climate change, water scarcity and soil poverty are becoming increasingly alarming, leading to growing losses of 30-50% of global agricultural production. It is imperative to find environmentally-friendly approaches for improving plant tolerance to drastic conditions, particularly in arid and semi-arid Mediterranean regions. Biostimulants based on symbiotic microbes are emerging as effective strategies for improving tolerance and agricultural productivity. This study aims to evaluate the effects of single and double inoculation of arbuscular mycorrhizal fungi (My) and plant growth-promoting bacteria (Ba) on the growth, physiological and biochemical traits of maize crop grown in compost (Co) amended soil under two irrigation regimes: well-watered (WW: 100% of crop evapotranspiration [ETc]) and drought-stressed (DS: 50% ETc) using drip irrigation system. Reducing irrigation to 50% reduced shoot dry weight (SDW), root dry weight (RDW), 1,000-grains weight (TGW) and grain yield (Y). However, Ba alone increased SDW by 63%, while CoMyBa improved RDW, TGW and Y by 197, 43 and 175%, respectively compared with the control under DS conditions. Dual inoculation boosted root colonization intensity, normalized difference vegetation index (NDVI), total chlorophyll and leaf area of maize seedlings in compost-amended soil, compared to the controls. The application of Ba significantly reduced hydrogen peroxide and malondialdehyde by 46%, in maize seedlings grown in compost-amended soil, compared to the controls under DS. Our results indicated that My and Ba significantly boost the ability of maize to tolerate drought by improving water supply and physiology and stimulating the accumulation of organic and inorganic osmolytes, as well as improving the properties of soils such as cation exchange capacity particularly amended by Co. The dual inoculations were the most effective and represent an environmentally-friendly and relatively inexpensive approach to optimizing agricultural production and soil restoration programs in Mediterranean regions.

Caatinga Microbiome Initiative: disentangling the soil microbiome across areas under desertification and restoration in the Brazilian drylands

The Caatinga biome in Brazil is renowned for its rich aboveground biodiversity. However, approximately 19% of this biome has experienced desertification, severely affecting the soil microbiome. Monitoring these microbial communities is essential to understanding the impacts of desertification and the potential outcomes of restoration efforts. The Caatinga Microbiome Initiative aims to assess the soil microbiome in areas undergoing desertification and those under restoration in the Brazilian drylands. This initiative seeks to explore the core microbial communities and their functions, including overlooked groups such as protists, nematodes, and viruses across native, desertified, and restored areas. We believe that two approaches should be used simultaneously in the study of microbiomes in areas undergoing desertification. First, the use of the soil microbiome as a bioindicator of soil quality in both desertified and restored lands. Second, the manipulation of the microbiome to facilitate soil restoration. By understanding soil microbiome responses to desertification and restoration, we can develop targeted restoration strategies to enhance biodiversity and promote functional recovery in desertified areas.

Water and nitrogen coupling regulates the present and future restoration trends under Spartina alterniflora invasion in a coastal salt marsh

Global change can easily cause the wetland ecosystem structure and function to be damaged by alien species. Former studies on Spartina alterniflora invasion only focused on the effect of aboveground communities, ignoring the potential regeneration of soil seed banks. Therefore, the study aimed to find the key resources that limit the S. alterniflora invasion and the regulation mechanism for S. alterniflora regeneration. Through investigating the S. alterniflora communities with different invasion stages, we studied the structure and composition of the aboveground communities and the soil seed banks, in response to the soil properties and water and nitrogen addition. The dominant competitive advantage of S. alterniflora was mainly affected by the aboveground biomass, which was regulated by soil NH4+-N and moisture content. Although the richness was same in the soil seed banks under the S. alterniflora communities with different coverage, S. alterniflora seeds maintained its specific competitive dominance. The niche breadth of S. alterniflora and the niche overlap between S. alterniflora and Tripolium pannonicum was the highest under low aboveground coverage. The soil seed bank germination experiments showed that the S. alterniflora density decreased when the soil nitrogen concentration exceeded 1 g/kg, while the density of native species E. crusgalli and T. pannonicum decreased when the water depth above the soil surface exceeded 2 cm. The successful naturalization of S. alterniflora invasion regulated by nitrogen-water coupling is a bet-hedging of the niche and fitness differences between invasive and native species in the coastal salt marsh of eastern China.

Circular economy strategies in sedimentary phosphate mine reclamation: Development of technosol from phosphate waste rock

Proper management of mine waste plays a crucial role in minimizing environmental impacts. One potential solution to tackle this problem involves transforming mine waste rock into soil to facilitate the process of mine restoration. The aim of this study was to assess the mineralogical, chemical, and physical characteristics of technosol derived from phosphate mine waste dumps. Following this evaluation, a novel rehabilitation strategy was proposed. For this purpose, a total of 32 samples were systematically collected across a 4 ha area of technosols, which had been established in accordance with the waste rock soil rehabilitation strategy involving geomorphic reshaping. According to the findings, phosphate mining left the soil with a sandy texture, resulting in a degraded soil structure with severely unfavorable crop growth conditions, notably poor stability, and low water retention. The chemistry of the studied soils was characterized by the dominance of CaO (29.02 wt%± 1.01) > SiO2 (27.61 wt% ± 0.61) > P2O5 (11.34 wt% ± 0.23) > MgO (5.97 wt%±0.16). Mineralogically, the samples were mainly formed by quartz, dolomite, calcite, apatite, and clay minerals. The prevalence of dolomite played a significant role in enhancing the accessibility of Mg as an essential nutrient and the occurrence of apatite in the soil resulted in the presence of P2O5. However, the abundance of Ca was linked to three major minerals: calcite, apatite, and dolomite. X-ray fluorescence analyses demonstrated that the concentrations of Fe2O3, K2O, and SO3 did not exceed 2 wt%.Organic matter, represented by SOC <0.2% and N < 0.02%, demonstrated an extraordinary deficiency in the study area. The analysis of element bioavailability confirmed that the soil was rich in Ca (10383,26 mg/kg), Mg (278,47 mg/kg), Zn (12,82 mg/kg), and Cu (3,7 mg/kg) but deficient in other essential nutrients such as P, K, S, Mn, and Fe. Our research results provide a set of recommendations aimed at enhancing existing mine rehabilitation practices applicable to both pre- and post-rehabilitation phases, leveraging automated mineralogy and circular economy principles. Notably, we propose a rehabilitation strategy to be implemented prior to the geomorphic reshaping phase, which is intended to reduce costs and efforts associated with soil reconstitution.