Carbonisation from Dicranopteris pedata clippings (REE/C) offer a sustainable strategy for the utilisation of phytoremediation biomass in rare earth element (REE) mining regions. In this study, physicochemical properties of REE/C were characterised, and their performance in immobilising Pb, Cu, and Cd in orchard soils was evaluated using soil passivation and leaching experiments. The results showed that REE/C was mainly amorphous carbon with a small graphitic fraction, and that agglomerated La-, Ce-, and Y-containing particles were precipitated on its surface, providing a high specific surface area of 439.48 m2 g-1 and strong adsorption capacity for heavy metals (HMs). REE/C application to contaminated agricultural soils promoted the transformation of acid-soluble and reducible HMs into oxidisable and residual fractions, thereby significantly reducing their mobility. The concentrations of Pb, Cu, and Cd in the leachates decreased to 5.46 %, 38.71 %, and 33.80 % of those in control, respectively. In addition, REE/C increased β-N-acetylglucosaminidase to 41.00 IU L-1 and leucine aminopeptidase to 95.61 IU L-1. It also increased total nitrogen and alkaline hydrolysable nitrogen by 2.59- and 1.55-fold, respectively, and improved microbial diversity and community structure. Pearson correlation and Mantel analyses indicated that soil microbial communities were closely associated with pH, organic matter, organic carbon, nutrient availability, and endogenous REEs. These findings demonstrate that REE/C can serve as an effective amendment for HMs immobilisation and agricultural soil remediation, with endogenous REEs playing an important role in the remediation process. This study provides a resource-efficient pathway for phytoremediation biomass valorisation and soil restoration in REE mining regions.

Deep-space conditions exert severe stress on plant genome stability, gene expression, epigenetic modification, and cell differentiation. In this study, multiomics analysis is used to observe changes in rice at the molecular and cellular levels after deep-space flight, including an increase in the frequency and types of mutations. While overall DNA methylation levels do not significantly change, CHG methylation levels present an increase that is correlated with DNA methylation responses. RNA presents significantly elevated m6A modification levels, which positively regulate gene expression. The proportion of mesophyll cells decreases, and 188 genes are identified as affecting the differentiation of mesophyll cells. Integrated multiomics analysis supports a hypothesis that the NAC family transcription factor suppressor of variation transmission 1 (SVT1) negatively regulates MAPK pathway genes, potentially influencing differentiation of cells harbouring mutations. Overall, this study comprehensively describes the molecular map of rice after deep-space flight and proposes a putative mechanism through which SVT1 may adapt to deep-space flight by inhibiting the differentiation of cells harbouring mutations.

Achieving sustainable land restoration in southern Chinese ionic rare earth mining areas remains a significant challenge due to the extended duration and low efficiency of conventional remediation approaches. Although the hyperaccumulator Dicranopteris pedata possesses a remarkable capacity for rare earth element (REE) enrichment, a significant knowledge gap exists regarding how to effectively combine exogenous organic acids with agronomic practices like clipping to enhance its remediation efficiency in an environmentally sustainable manner. Crucially, the potential environmental risks associated with such synergistic strategies have not been systematically evaluated, hindering their practical application. To address this, our study focused on Dicranopteris pedata and employed integrated pot and soil column leaching experiments to systematically analyze the effects of different concentrations of citric acid and tartaric acid on REE migration and transformation within the soil-plant system. The results demonstrated that exogenous organic acids significantly reduced soil pH and promoted the conversion of REEs from the residual to the exchangeable fraction. Specifically, the 20 mmolkg-1 citric acid treatment increased the proportion of exchangeable REEs by 43.46%. Furthermore, organic acid treatments significantly altered the REE uptake patterns in Dicranopteris pedata, inhibiting the translocation and accumulation of REEs in the aboveground tissues. Soil column leaching experiments revealed that citric acid drove the migration of REEs to deeper soil layers, with the concentration peaking at 288.33 mgkg-1 at a depth of 6-8 cm; concomitantly, the REE content in the leachate reached its maximum on the 5th day. This study demonstrates that the combined application of 20 mmolkg-1 citric acid and 100% clipping management increased the annual REE accumulation in Dicranopteris pedata to 4.85 gm-2, thereby significantly shortening the theoretical remediation period from 25.0 years in the control to 12.1 years. Soil column leaching experiments indicated no significant secondary pollution risk associated with this strategy. These findings provide a feasible, low-risk, and sustainable technical strategy for the synergistically enhanced remediation of REE-contaminated soils, offering a promising path for ecological restoration and sustainable land management in degraded mining ecosystems.

Obtaining accurate spatial information on soil organic matter (SOM) is crucial for understanding global carbon cycle. Digital soil mapping (DSM) has become an effective method for mapping SOM, in which selection of influential environmental covariates plays an important role. Soil moisture (SM) can serve as a potential covariate, especially it can be estimated at large spatial scales thanks to remote sensing. The normalized shortwave- infrared difference bare soil moisture indices (NSDSIs) based on Landsat SWIR bands generated at bare soil period has been employed in SOM mapping previously. However, soil is usually covered by vegetation, it is thus necessary to develop new SM indices applicable to areas covered with vegetation, and examine how SM indices perform in areas with different vegetation densities. In this paper, we developed a new SM index by introducing NSDSIs to the Optical TRApezoid Model (OPTRAM-NSDSI), and compared it with the original OPTRAM with the shortwave infrared transformed reflectance (OPTRAM-STR), as well as NSDSIs. SM indices were generated across two study areas, i.e. Zhuxi, Fujian (104 samples and 43.93 km2 with forestland and farmland as main land uses) and Heshan, Heilongjiang (106 samples and 60 km2 with primarily farmland) in China. The Integrated Nested Laplace Approximation with the Stochastic Partial Differential Equation approach was utilized as the SOM prediction model. The results suggest that adding SM variables into the commonly-used environmental covariates improves the prediction accuracies. The highest accuracy improvement of 26.8% in terms of Lin's concordance correlation coefficient in Zhuxi is obtained by NSDSIs, and the highest improvement of 56.7% in Heshan is obtained by OPTRAM-NSDSI. This may indicate that OPTRAM-NSDSI is more effective in areas with higher vegetation densities while NSDSIs in areas with lower densities. Furthermore, the optimal image dates for SM estimation are probably at the vegetation "green-up" stage. This study provides a reference for using SM information to improve SOM mapping in areas covered with vegetation.

Rare earth elements (REEs) are key resources of strategic importance, but pollution has increased due to uncontrolled mining. Although heavy metal hyperaccumulating plants are environmentally friendly, they require strict control during post-treatment, or they may cause secondary pollution. Therefore, their safe disposal plays a key role in the ecological restoration of REE mines. In this study, rare earth element (REE)-rich biochar was produced by pyrolyzing the REE hyperaccumulator Dicranopteris pedata. This biochar was then applied to the Citrus grandis (L.) Osbeck. cv. Guanximiyou soil amendment experiment to evaluate its effects on soil physicochemical properties and microbial indicators. Four treatments were established: CK (0% REE-rich biochar), BC1 (1% REE-rich biochar), BC3 (3% REE-rich biochar), and BC5 (5% REE-rich biochar). The BC5 treatment decreased soil REE bioavailability, thereby preventing REE pollution. The BC5 treatment also demonstrated the highest efficacy in improving soil total organic carbon (229.11%), total nitrogen (53.92%), total phosphorus (55.61%), total potassium (55.50%), available nitrogen (14.76%), available phosphorus (46.79%), and available potassium (159.42%) contents compared to CK. Furthermore, soil enzyme activities were significantly increased by BC5 treatment (p < 0.05). At the bacterial phylum level of classification, the bacterial diversity index (Chao1 and Shannon) exhibited elevated levels under BC5 conditions. Furthermore, the Chao1 index of fungal diversity exhibited a substantial augmentation of 55.67% (p < 0.05) in the BC5 treatment in comparison to the CK, and also significantly higher than the other treatments (p < 0.05). Our study showed that the composition of soil microorganisms was altered by REE-rich biochar. Proteobacteria, Acidobacteria, Actinobacteriota, and Chloroflexi are dominant among bacteria, while Ascomycota is dominant among fungi. Mantel and redundancy analyses showed that the most important environmental factor affecting the structure of soil microbial communities was pH, especially in the case of bacteria. In summary, this study showed that the application of 5% REE-rich biochar provided the best improvement in soil physicochemical properties and microbial diversity. These findings highlight its potential for soil remediation and provide new ideas for recycling heavy metal hyperaccumulating plant waste.

Microplastic pollution in marine environments has become a global concern due to its potential ecological risks. However, long-term data on microplastic distribution are scare, hindering the assessment of the ecological threats. This study monitored microplastics pollution in the surface water of the northern South China Sea from 2019 to 2023. The average abundance of microplastics exhibited an increasing trend from 2019 to 2021 and a subsequent decrease from 2021 to 2023 in both the Pearl River Estuary and Zhanjiang offshore waters. Conversely, a steady annual decrease was observed in the surface waters of Beibu Gulf from 2020 to 2023. The spatial variability of microplastic hotspot across different years and regions. Microplastics predominantly ranged from 1 to 2 mm in size, with fragments and fibers being the most common shapes and transparent and white colors being the most prevalent. The primary chemical components of microplastics were polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET). No significant inter-annual differences were observed in the physicochemical characteristics of microplastics. The pollution load index (PLI) indicated medium to low levels of microplastic pollution, with the potential ecological risk index (PERI) suggesting a low level of ecological risk, implying a minimal threat to the marine ecosystem. This study first revealed the annual variations in microplastic pollution and their potential ecological risks in the northern South China Sea, providing crucial data support for the future management and control of marine microplastic pollution.

The escalating demand for rare earth elements (REEs) necessitates innovative strategies for their recovery from unconventional resources like mining wastewater. However, achieving high selectivity in such complex, multi-ion matrices remains a formidable challenge. This study introduces a novel approach for the rapid and highly selective extraction of 15 REEs from authentic mining effluent using magnetic MnFe2O4 nanoparticles. The synthesis strategy uniquely combines a benign, plant-extract-based precursor step with a subsequent thermal treatment to engineer the desired high-performance spinel phase, thus avoiding hazardous chemical reductants. The resulting MnFe2O4 nanoparticles exhibit exceptional group selectivity, with distribution coefficients (K-d) for REEs that are two to four orders of magnitude higher than those for competing alkali, alkaline earth, and heavy metal ions (Separation Factor, SF > 10(2)). Detailed characterization, corroborated by Density Functional Theory (DFT) calculations, reveals that the Mn sites on the (220) crystal facet are the primary active centers for this selective binding. Furthermore, the adsorbent demonstrates excellent practical applicability, achieving > 95 % desorption efficiency under optimized acidic conditions and maintaining robust performance over five consecutive adsorption-desorption cycles (>90 % efficiency). A comprehensive Life Cycle Assessment (LCA) quantitatively validates the environmental benefits of our approach, demonstrating significantly lower impacts (e.g., an 8-fold reduction in GWP compared to the hydrothermal method) compared to conventional synthesis routes. This work not only presents a highly effective and recyclable magnetic adsorbent for valorizing low-concentration waste streams but also provides a holistic, LCA-validated framework for designing genuinely sustainable separation technologies.

This study aimed to develop an aromatic thermosensitive genic male sterile (TGMS) line in indica rice using CRISPR/Cas9 technology. The TMS5 and FGR in the high-quality conventional rice variety Huahang 48 were targeted for editing using CRISPR/Cas9 technology. CRISPR/Cas9 vectors designed for TMS5 and FGR were constructed and introduced into rice calli through Agrobacterium-mediated transformation. Transgenic seedlings were subsequently regenerated, and the target sites of the edited plants were analyzed via sequencing. A total of fifteen T0 double mutants were successfully obtained. Three mutants without T-DNA insertion were screened in the T1 generation by the PCR detection of hygromycin gene fragments, and homozygous mutants without T-DNA insertion were screened in the T2 generation by the sequencing analysis of the mutation sites, named Huahang 48s. Huahang 48s exhibited complete sterility at 24 °C and pollen transfer at 23 °C. The 2-acetyl-1-pyrroline (2-AP) content was detected in the young panicles, leaves, and stems of Huahang 48s. The leaves of Huahang 48s had the highest 2-AP content, contrasting with the absence of 2-AP in HuaHang 48. F1 hybrids that crossed Huahang 48s with two high-quality restorer lines were superior to the two parents in terms of yield per plant and 1000-grain weight. Huahang 48s has a certain combining ability and application potential in two-line cross breeding. The successful application of CRISPR/Cas9 technology in Huahang 48 established a foundation for developing aromatic TGMS lines, providing both theoretical insights and practical materials for breeding efforts.

Phytoremediation is currently a very popular remediation method for salvaging rare earth mining sites. However, there is still a challenge concerning how to use secondary resources such as plant biomass following the extraction of rare earth elements (REEs). Herein, Dicranopteris pedata (Houtt.) Nakaike, a REEs hyperaccumulator, served to fabricate REEs-rich carbonisation materials (REEs/C) at different temperatures. The results showed that the percentages of Pb(II) removed using REEs/C prepared at 400 °C (REEs/C-4) and 800 °C (REEs/C-8) were 85.1% and 84.0%, respectively. These amounts were better than that of REEs-C prepared at 600 °C (REEs/C-6 (67.0%)). Characterisation analysis confirmed that rich functional groups like aromatic, hydroxyl and C = C/C-C in REEs/C-4 provided more chelation sites to effectively complex with Pb(II), while the superior removal capacity of REEs/C-8 resulted from the enrichment of more REEs and abundant pore structure. Chemisorption, such as ion exchange and chelation, plays a significant role in adsorption. During the carbonisation process of REEs/C, the REEs enriched in Dicranopteris pedata contributed to the formation of rare earth oxides and oxygen vacancies in the material, and these properties enhanced the Pb removal ability of REEs/C. Moreover, the REEs contained in the material did not cause a leaching phenomenon during Pb removal, which is a safe and environmentally friendly material. Finally, the REEs/C was applied to wastewater, and it was found that this material could effectively adsorb Pb from wastewater. Overall, this study generates a new insight into: firstly, how to use phytoextracted biomass containing REEs as valuable REEs/C materials; and secondly, how to save the environment by using technology that promotes recycling of used materials.

Rare earth elements (REEs) have emerged as critical metallic resources in modern industries due to their unique physicochemical properties. However, rare earth elements are inevitably discharged into environments during mining operations, leading to impact the ecosystem and to loss rare earth elements. To address this, the carbonized Fe/Mn nanomaterials (C-Fe/Mn) were synthesized through green carbothermal reduction to achieve efficient recovery of rare earth elements. It can be seen that the maximum adsorption efficiencies of REEs by synthesized material were yttrium (Y(III) 98.28 %), lanthanum (La(III) 97.37 %), dysprosium (Dy(III) 88.75 %), and ytterbium (Yb(III) 77.27 %), respectively. Through advanced characterization, C-Fe/Mn's magnetic properties have been confirmed, which enables direct recovery from wastewater and easy separation in application. The results showed that the carbon coating provides additional active sites, thereby enhancing its adsorption capacity, while the presence of zerovalent iron lattice improves its stability. Therefore, its efficient adsorption of rare earth elements is mainly attributed to the combined effect of complexation and electrostatic force. Finally, column experiments demonstrated that rare earth elements can be effectively removed and desorbed by C-Fe/Mn under continuous flow, indicating its potential for practical application. Overall, this approach not only mitigates environmental pollution but also promotes resource recycling, offering dual economic and ecological benefits.

Analyzing the changes in agricultural carbon emissions (ACE) and their influencing factors can provide a sound basis for accurately estimating the carbon balance of agroecosystems. Such analyses can serve as a reference for developing policies to mitigate global climate change and promote sustainable agricultural development. Using the carbon emission calculation framework of the Intergovernmental Panel on Climate Change, this study examined the spatiotemporal characteristics of ACE, including total amount, intensity, structure and their influencing factors, in Fujian Province from 2002 to 2022. The logarithmic mean scale index model and Tapio decoupling model were used, with the GM (1,1) model to forecast carbon emissions from 2023 to 2040. The results indicate that both the total emissions and intensity of ACE had fluctuating downward trends and agricultural material inputs were the largest contributors to ACE. Additionally, total ACE was found to have a spatial pattern higher in the west and lower in the east and agricultural production efficiency was the primary factor in reducing ACE. ACE was clearly decoupled from economic development and is projected to continually decline after 2023.

The post-treatment of heavy metal-enriched plants in mining areas and the purification of ammonia and nitrogen pollution in water bodies are significant for the ecological environment of ionic rare earth mining areas. Herein, we focused on the biochar production potential of Dicranopteris pedata, characterizing biochar prepared by an oxidative modification process and an iron modification process. We conducted adsorption experiments to comparatively investigate the adsorption performance of biochar on NH4+ and studied the fertilizer application and migration toxicity of the adsorbed biochar for rare earth elements (REEs). Results indicated that ~332.09 g of biochar could be produced per unit area of D. pedata under 100% clipping conditions. The Brunauer–Emmett–Teller (BET) specific surface area of oxidized biochar (H2O2BC) increased, and the pore size of iron-modified biochar increased. The adsorption behavior of biochar toward NH4+ was well represented by the pseudo-second-order and Langmuir models. H2O2BC demonstrated the strongest adsorption of NH4+ with maximum theoretical equilibrium adsorption of 43.40 mg·g−1, 37.14% higher than that of pristine biochar. The adsorption process of NH4+ on biochar is influenced by various physicochemical mechanisms, including pore absorption, electrostatic attraction, and functional group complexation. Furthermore, the metal ions in the biochar did not precipitate during the reaction process. The adsorbed NH4+ biochar promoted the growth of honey pomelo without risking REE pollution to the environment. Therefore, it can be applied as a nitrogen-carrying rare earth fertilizer in low rare earth areas. This study provides a theoretical basis and technical support for the phytoremediation post-treatment of rare earth mining areas and the improvement of ammonia nitrogen wastewater management pathways in mining areas.

The ion adsorption rare earth (IARE) mining areas in southern China frequently experience severe seasonal drought, posing significant challenges to plant growth. This study investigates the hypothesis that rare earth elements (REEs) present in these mining areas induce drought resistance in Dicranopteris pedata (D. pedata). An experiment was designed with three drought stress intensities (0%, 5%, and 10% PEG6000) and three levels of rare earth element (REE) addition (none, low, and high). After 72 h of drought stress, physiological indices and metabolomic profiles of D. pedata were examined. The results showed that under drought conditions, the REE additions increased the catalase and peroxidase activities of D. pedata by 99.04% and 81.25%, respectively, and the contents of proline, soluble proteins, and soluble sugars by 97.52%, 71.24%, and 61.81%, respectively. Metabolomic analysis revealed up-regulation of lipid and lipid-like molecules, as well as flavonoid metabolism, which contribute to improved drought resistance in D. pedata under stress. Furthermore, REE addition further up-regulated flavonoid and anthocyanin synthesis compared to drought stress alone, enhancing the plant’s resilience to drought. These findings suggest that D. pedata responds to drought stress by modulating enzyme activities, osmoregulatory substances, and metabolic pathways upon REE exposure. This study underscores the dual role of REEs in enhancing both the drought tolerance and enrichment capacity of D. pedata in IARE mining areas, which is crucial for sustaining plant growth amidst drought stress, and provides new ideas for the ecological restoration and sustainable development of IARE mining areas.

Clipping is crucial during phytoremediation. However, research into the effects of clipping intensity on the physiology of Dicranopteris pedata (D. pedata) and its interroot soil in the rare-earth-mining area in southern China is lacking. A clipping experiment was conducted to verify the phytoremediation effect of D. pedata. The physiology of D. pedata, such as biomass, antioxidant enzymes, chlorophyll, and rare-earth elements (REEs), were determined after clipping. And the microbial community diversity and soil enzyme activities in the interroot soil of D. pedata were investigated. The phytoremediation efficiency was determined at the end of the experiment. The results showed that the compensatory growth effect of D. pedata was stronger with increasing clipping intensity. There was no significant difference in the α diversity of interroot soil microorganisms of D. pedata at different clipping intensities, but β diversity analysis showed that the clipping treatment group deviated from the control group. Only urease activity decreased among the interroot soil enzymes in D. pedata after clipping, while the soil catalase and sucrase were less responsive to clipping. The REEs accumulated by D. pedata were dominated by light REEs in the aboveground part of the plant, while the amounts of light and heavy rare-earth elements accumulated in the underground part of the plant were similar. The phytoextraction of REEs gradually increased with increasing clipping intensity. It was concluded that 100% clipping once a year is the most appropriate when considering D. pedata’s phytoremediation potential and soil system. The time it takes for 100% clipping of D. pedata to reduce the soil TREEs (total rare-earth elements), LREEs (light rare-earth elements), and HREEs (heavy rare-earth elements) to below-average soil REE concentration in China was estimated to be 25.54 years, 19.56 years, and 65.43 years, respectively, which was significantly lower than that for other clipping intensities and the control group. It is concluded that clipping D. pedata is an effective way to promote phytoextraction efficiency in the southern rare-earth-mining areas. The soil can still support the resumption of D. pedata growth after high-intensity clipping.

Our understanding of how varying clipping intensities affect the efficiency of phytoextraction remains limited, particularly with co-cropping systems. This study focuses on assessing the effects of different clipping intensities on phytoextraction efficiency within co-cropping systems dominated by the key species Dicranopteris pedata and Pinus massoniana in rare-earth mines of southern China. Our results confirmed the following. Firstly, the compensation index, dry aboveground biomass, and rare-earth elements (REE) accumulation of clipped D. pedata per unit area were highest under 100% clipping (p < 0.05). Meanwhile, the bioabsorption coefficient, bioconcentration factor, and translocation factor of P. massoniana were less than 1. Secondly, the soil catalase, sucrase, and alpha-diversity indices of bacteria and fungi separately indicated no significant variation between the clipping treatments and control. The REE content in tree rings increased, and the total REE contents in thicker tree rings were higher than those in the thinner tree rings of P. massoniana from 1997 to 2016. Additionally, the soil erosion intensity diminished significantly in the growth area of P. massoniana from 1995 to 2019. Thirdly, both D. pedata and P. massoniana, when subjected to 100% clipping, could effectively remove excess REEs from the 0-20 cm soil layer within 18.57-61.19 years. In contrast, P. massoniana alone achieved a removal rate of excess REEs in the 20-60 cm layer, within 923.16-1899.62 years. Thus, D. pedata with 100% clipping can phytoextract the maximum amount of REEs. It is noted that P. massoniana cannot be used for REEs phytoextraction or phytostabilization. Co-cropping with 100% clipping would have a less negative impact on growth and REEs extraction, and the co-cropping system can phytoextract excess REEs from the surface soil within decades. However, it is not efficient for the phytoextraction of excess REEs from deep soil layers.

Due to their use in a number of advanced electronic technologies, Rare earth elements (REEs) have recently emerged as a key strategic resource for many nations worldwide. The significant increase in demand for REEs has thus greatly increased the mining of these substances, but this industrial-scale expansion of mining activities also poses potential risks to the surrounding environment, flora, fauna, and humans. Hence efficient REE remediation is one potential remediation process involving in situ clean-up of contaminated soil which has gained much attention in recent years, due to its low cost and lack of secondary pollution. However, some crucial aspects of phytoremediation, such as the precise-mechanisms of absorption, transport, and tolerance of REEs by hyperaccumulators -are poorly understood. This review briefly discusses the environmental risks associated with excess REEs, the efficacy of phytoremediation technologies coupled with, appropriate hyperaccumulator species to migrate REEs exposure. While REEs hyperaccumulator species should ideally be large-biomass trees and shrubs suitable for cropping in subtropical regions areas, such species have not yet been found. Specifically, this review focuses on the factors affecting the bioavailability of REEs in plants, where organic acids are critical ligands promoting efficient transport and uptake. Thus the uptake, transport, and binding forms of REEs in the above-ground parts of hyperaccumulators, especially the transporters isolated from the heavy metal transporter families, are discussed in detail. Finally, having summarized the current state of research in this area, this review proceeds to discuss current knowledge gaps and research directions. With a focus on hyperaccumulators, this review serves as a basis for future phytoremediation strategies of rare earth mining-impacted environments and addresses ecosystem/environmental degradation issues resulting from such mining activity.

With severe soil and water erosion, the crucial ion-adsorption rare earth elements (REEs) have attracted much global attention. REEs play a vital role in tracing material sources and exploring sedimentary characteristics due to their unique and stable geochemistry properties. In the present work, three representational possible redeposition areas in western Fujian were selected as the study areas. The geochemical characteristics of REEs in the sediments of the study areas were evaluated to elucidate that REEs are the products of soil and water erosion and to assess their redeposition characteristics. In the research results, the properties of the parent rocks shown in the samples, together with the negative correlation between the content of REEs in the samples and altitude as well as the relief degree on the land surface (RDLS), fully indicate that the sediments in the study areas are the products of migration caused by soil erosion and redeposition in the downstream areas. At the same time, according to the widely applicable standard of rare earth resources exploitation, that is the boundary grade of ion-adsorption rare earth ore in southern China (∑REE = 500 mg·kg−1), we found that the content of REEs in the study areas was close to or exceeded this standard, and the maximum ∑REE of Guozhai Reservoir (869.11 mg·kg−1) was much larger than this standard. Therefore, the redeposited rare earth in Changting Country has high reuse potential under the current scarce resources.

The migration and enrichment of rare earth after mining activities pose a significant environmental threat to the surrounding habitants. We conducted a study at the Zhuxi watershed to analyze the rare earth element distribution in the topsoil after mining activities. Our findings reveal that the rare earth elements content in the top soil of the watershed shows a decreasing trend from the eastern area to the western area. The distribution of each element indicated that the crust abundance had the greatest influence. Mining activities can affect the fractionation of rare earth elements. The ecological risk assessment of rare earth elements necessitates comprehensive assessments, as the geoaccumulation method weakens the impact of a single element.

Ideal Plant Architecture 1 (IPA1) is a key regulator of plant architecture. However, knowledge of downstream genes applicable for improving rice plant architecture is very limited. We identified the plant architecture regulatory gene NARROW LEAF 11 (NAL11), which encodes a heat-shock protein (HSP) containing a DnaJ domain. A promising rare allele of NAL11 (NAL11-923del-1552 ) positively selected in Aus cultivars was identified; this allele exhibited increased expression and generated relatively few tillers, thick stems, and large panicles, components of the ideal plant architecture (IPA). NAL11 is involved in regulating the cell cycle and cell proliferation. NAL11 loss-of-function mutants present impaired chloroplast development and gibberellin (GA) defects. Biochemical analyses show that IPA1 directly binds to elements in the missing fragment of the NAL11-923del-1552 promoter and negatively regulates NAL11 expression. Genetic analyses support the hypothesis that NAL11 acts downstream of IPA1 to regulate IPA by modulating GA homeostasis, and NAL11 may be an essential complement for IPA1. Our work revealed that avoidance of the inhibition of NAL11-923del-1552 caused by IPA1 represents a positive strategy for rescuing GA defects accompanied by the upregulation of IPA1 in breeding high-yield rice.