The relationship between landscape patterns and soil conservation, as well as the need for nature-based soil erosion control and landscape pattern optimization, have increasingly gained attention in ...the scientific and political community in the past decade. With the implementation of a series of afforestation/reforestation projects in the western China, the optimization and management of forest landscape patterns will become more important for soil conservation. In this study, the Bailongjiang Watershed (BLJW), in the western China, was used as a case study to explore the relationship between the forest landscape pattern and soil conservation services using mathematical and spatial statistics methods. A spatially-explicit model called the sediment delivery ratio (SDR) model of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) was used to assess the soil conservation service in each sub-basin of BLJW in 1990, 2002, and 2014, and landscape indices were used to describe changes in forest landscape patterns in each sub-basin. Nine forest landscape indices, including the percentage of landscape (PLAND), largest patch index (LPI), edge density (ED), landscape shape index (LSI), mean patch shape (SHAPE_MN), patch cohesion index (COHESION), landscape division index (DIVISION), splitting index (SPLIT) and aggregation index (AI), were significantly correlated to the soil conservation service. PLAND, AI, LSI and SPLIT of forestland were determined to be the more important landscape indicators. The results also indicated that soil conservation was substantially scale-dependent. The results demonstrated that landscape type diversity greatly affected watershed soil conservation and can be used for forest landscape restoration and management. Furthermore, spatial statistics analysis indicated that the Spatial Lag Model (SLM) was superior to the Ordinary Least Squares (OLS) for soil conservation regressions in 1990 and 2014, while OLS was more appropriate for the regression in 2002. These findings will be useful for enhancing soil conservation and for optimizing mountainous forest landscape patterns for afforestation/reforestation and regional development. Future planning and implementation of ecological restoration should focus more on strategic spatial planning and integrated landscape management with full consideration of future climate, water availability/consumption, hydrological regime, topography, and watershed features, especially on afforestation and revegetation projects in western mountainous China, where the socio-ecological system is fragile and poor.
There is an increasing interest in introducing ecosystem services (ESs) and landscape ecological risk (LER) into environmental policies and governance. Yet, we know little about how to integrate LER ...into real decision-making and ESs management. Using the ESs valuation method and the models of InVEST and LER, this study analyzed the spatiotemporal changes of cropland food production, carbon storage, water yield, biodiversity index and LER of Bailongjiang watershed (BLJW), China in 1990, 2002 and 2014, and the relationship between them. We found clear spatial differences in both ESs and LER levels in BLJW during the study period. The cropland food production service kept rising, and the areas of high yield mainly distributed in the loessal regions of BLJW with intensive human population. The carbon storage, water yield and biodiversity index first decreased and then increased. The LER was higher in the areas along the valleys with low elevation and intensive human activities. The regional ecological zoning based on overlay analysis of ESs with LER is effective for providing interactive spatial knowledge for adaptive landscape management. Our results illustrate the integrative approach on linking landscape ecological risk with ecosystem services is a comprehensive and helpful methodology for both regional risk reduction and ecosystem services enhancement at landscape scale.
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•Watershed ecosystem services and landscape ecological risk were assessed and mapped.•Clear spatial changes in ecosystem services and landscape ecological risk were found.•A novel method proposed to link landscape ecological risk with ecosystem services.•Overlay zoning lays scientific foundation to implement adaptive landscape management.
Chimeric antigen receptor T (CAR-T) cells therapy is a milestone achievement in the immunotherapy of relapsed and refractory (R/R) B cell acute lymphoblastic leukemia (B-ALL). However, some patients ...treated with CAR-T cells do not achieve complete remission, the mechanisms of which have not been elucidated. In the present study, we report a 9-year-old pediatric patient with refractory B-ALL received a triple infusion of autologous CD19 CAR-T cells therapy after the second relapse. CAR-T cells expanded in the peripheral blood and bone marrow. However, the patient did not achieve complete remission, indicating a lack of response to CAR-T cells therapy. Analysis of etiological factors revealed that the number of CD4 and CD8 double-negative T (DNT) cells was significantly upregulated in the peripheral blood, bone marrow, and autologous CAR-T cells products. In conclusiont, these findings indicate that DNT cells mediated resistance to CAR-T cells therapy in this pediatric patient with R/R B-ALL.
Microorganisms play an important role in soil phosphorus (P) cycling and regulation of P availability in agroecosystems. However, the responses of the functional and ecological traits of ...P-transformation microorganisms to long-term nutrient inputs are largely unknown. This study used metagenomics to investigate changes in the relative abundance of microbial P-transformation genes at four long-term experimental sites that received various inputs of N and P nutrients (up to 39 years). Long-term P input increased microbial P immobilization by decreasing the relative abundance of the P-starvation response gene (phoR) and increasing that of the low-affinity inorganic phosphate transporter gene (pit). This contrasts with previous findings that low-P conditions facilitate P immobilization in culturable microorganisms in short-term studies. In comparison, long-term nitrogen (N) input significantly decreased soil pH, and consequently decreased the relative abundances of total microbial P-solubilizing genes and the abundances of Actinobacteria, Gammaproteobacteria, and Alphaproteobacteria containing genes coding for alkaline phosphatase, and weakened the connection of relevant key genes. This challenges the concept that microbial P-solubilization capacity is mainly regulated by N:P stoichiometry. It is concluded that long-term N inputs decreased microbial P-solubilizing and mineralizing capacity while P inputs favored microbial immobilization via altering the microbial functional profiles, providing a novel insight into the regulation of P cycling in sustainable agroecosystems from a microbial perspective.
Heavy-metal contamination in soil has long been a persistent challenge and the utilization of agricultural waste for in-situ stabilization remediation presents a promising approach to tackle this ...problem. Agricultural wastes exhibit promising potential in the remediation of contaminated land and modification could improve the adsorption performance markedly. Citric acid and Fe3O4 treated sugarcane bagasse adsorbed more heavy metals than raw materials in the aqueous system, employing these materials for heavy metal remediation in soil holds significant implications for broadening the raw material source of passivators and enhancing waste utilization efficiency. In this paper, a 120-day soil incubation study was conducted to compare the effects of pristine sugarcane bagasse (SB), citric-acid modified (SSB1, SSB2 and SSB3 with increasing proportion of citric acid) and citric-acid/Fe3O4 modified (MSB1, MSB4 and MSB7 with increasing proportion of Fe3O4) sugarcane bagasse at 1 % addition rate on cadmium (Cd) and copper (Cu) passivation. The SB, SSB1 and MSB1 did not always decrease the content of CaCl2-extractable Cd while all the seven amendments decreased the CaCl2-extractable Cu during the experiment period. Among all materials, SSB3 and MSB7 exhibited the highest efficiency in reducing the concentrations of CaCl2-extractable Cd and Cu. At Day 120, SB, SSB3 and MSB7 reduced the content of CaCl2-extractable Cd by 8 %, 18 % and 24 %, and of CaCl2-extractable Cu by 25 %, 50 % and 61 %, respectively. The efficiency of Cd and Cu immobilization was associated positively with the pH, functional groups and H-bonds of the amendments. The results suggest that the efficiency of sugarcane bagasse in heavy-metal passivation can be largely enhanced through chemical modifications using high proportions of citric acid and Fe3O4.
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•Novel sugarcane bagasse (SB)-based amendments immobilize Cd and Cu in soil.•The amendments are more effective to immobilize Cu than Cd.•SSB3 and MSB7 exhibit the best performance in passivating both Cd and Cu.•CaCl2-extractable Cd is the main component of acid-soluble Cd.•Cd and Cu immobilization results from high pH, functional groups and H-bonding.
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•Calcium-based magnetic biochar has a great adsorption capacity for As and Cd.•This study elucidates mutual effects of Cd(II) and As(III) on their adsorption.•Both competition and ...synergistic effects exist between Cd(II) and As(III).•The synergistic effect is controlled by formation of type B ternary complex.
A novel calcium-based magnetic biochar (Ca-MBC), made by pyrolyzing the mixture of rice straw, iron oxide (Fe3O4) and calcium carbonate (CaCO3), was developed in this study for remediation of co-pollution of arsenic and cadmium. Characteristics of the material showed that Fe3O4 and CaCO3 were adhered on the surface of biochar. The experiments on the effects of pH, adsorption kinetics and isotherm revealed that the Ca-MBC had a great ability to adsorb arsenic and cadmium within 0.5 h for cadmium and 12 h for arsenic with a maximum adsorption capacity of 6.34 and 10.07 mg g−1, respectively, and that the adsorption of both metals was pH-dependent from 2 to 12 with an optimal pH of pH 5. The mechanism of co-adsorption of Cd(II) and As(III) included both competitive and synergistic effects. The presence of As(III) enhanced Cd(II) adsorption by 3–16% while Cd(II) addition suppressed As(III) adsorption by 15-33%. The synergistic effects on As(III) and Cd(II) adsorption had resulted from the electrostatic interaction and the formation of type B ternary surface complexes. These new insights provide valuable information for the application of Ca-MBC as a potential adsorbent in treatment of water contaminated with As(III) and Cd(II).
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•MGO showed the best adsorption capacities for TC, Cd(II) and As(V) among three magnetic graphene nanomaterials.•Adsorption behaviors of MGO in three different types of binary systems ...were systematically studied.•Mutual effects of TC and Cd(II) in the simultaneously added system were negligible.•Adsorption of As(V) was significantly suppressed in the presence of TC.•Cd(II) and As(V) were co-adsorbed by MGO via electrostatic attraction and formation of type A ternary surface complexation.
The adsorption of tetracycline (TC), cadmium Cd(II) and arsenate As(V) onto magnetic graphene oxide (MGO), magnetic chemically-reduced graphene (MCRG) and magnetic annealing-reduced graphene (MARG) was investigated to understand the adsorption properties and molecular mechanisms. The adsorption of three contaminants was pH-dependent and the adsorption capability followed the order of MGO > MCRG > MARG, and hence MGO was selected to systematically study the adsorption behaviors in three different types of binary systems. The maximum adsorption capacities of MGO were 252 mg/g for TC, 234 mg/g for Cd(II) and 14 mg/g for As(V). The superiority of MGO was mainly attributed to its high dispersibility, thin nanosheets and various O-containing functional groups. In addition to H-bonding and π–π interactions, the strong adsorption of TC onto MGO was mainly due to the n–π electron-donor–acceptor (EDA) effect, with the maximum adsorption around pKa of TC. The mutual effects of TC and Cd(II) in the simultaneously added system were negligible. Adsorption of As(V) was significantly suppressed in the presence of TC, whilst As(V) hardly affected TC adsorption. The adsorptions of Cd(II) and As(V) in the co-adsorption system were increased by 65% and 30%, respectively. This synergistic effect resulted from the electrostatic attraction and the formation of type A ternary surface complexation. These new insights were valuable for elucidating the interaction mechanisms and designing novel adsorbents for traditional and emerging pollutions in practical application.
Organochlorine pesticides have been extensively used for many years to prevent insect diseases of rice (Oryza sativa L.), but little is known about their residual impacts on the underground ...micro-ecology in anaerobic environment. In this glasshouse study, we characterized the lindane effects on the assembly of root-associated microbiomes of commonly used indica, japonica and hybrid rice cultivars, and their feedback in turn, in modifying lindane anaerobic dissipation during 60 days' rice production. The results showed that rice growth inhibited the anaerobic dissipation of lindane, but was not affected apparently by lindane at initial spiked concentration of 4.62 and 18.54 mg kg−1 soil. Suppressed removal of lindane in rice planted treatments as compared with that in unplanted control was likely due to inhibited reductive dechlorination induced by a comprehensive effect of radial O2 secretion of rice root and co-occurring Fe(III) reduction that consumed electron competitively in rice rhizosphere. However, the hybrid cultivar exhibited a less suppression than the conventional cultivars in high polluted soils. Bacteria was more sensitively responded to lindane pollution than fungal taxa, and Actinobacteria, Chloroflexi, Verrucomicrobia and Proteobacteria were the main different phyla between hybrid and conventional cultivars, with a more stable community structure exhibited in the hybrid rice under lindane stress. Our study highlights the assembly and variation of root-associated microbiomes in responses of lindane pollution, and suggests that hybrid rice cultivar might be most competent for cultivation in paddy fields polluted by lindane and other organochlorine pesticides, especially in the area with high residual levels.
•Rice growth inhibited the dissipation of lindane with hybrid cultivar having a less suppression than conventional cultivars.•Lindane and cultivar significantly affected the assembly of rice root-associated bacterial and fungal microbiomes.•The endosphere and rhizosphere compartments showed the greatest divergence.•A more stable community structure exhibited in the hybrid rice cultivar under lindane stress.•Hybrid rice might be the most competent cultivar for paddy fields polluted by organochlorine pesticides such as lindane.
The application of biochars for the remediation of water and soils contaminated with potentially toxic elements (PTEs) has seen a recent growing interest. The mechanisms of chemical immobilization of ...PTEs with biochars in aqueous media have been well defined. However, immobilization mechanisms by which biochars interact with PTEs in soil matrix are more complex. The biological immobilization mechanisms and their interactions with PTEs in biochar-amended soils are not as well defined. This review presents an overview of factors governing interactions of biochars with PTEs as well as the synergistic effect of biochars and microorganisms in biological immobilization processes. The effectiveness of biochars in improvement of microbial immobilization of PTEs mainly depends on biochar properties, application rates, and soil environments such as organic matter content, clay type and content, pH and redox potential. Although some modified biochars appear to be better than the pristine biochars for immobilization of PTEs, their potential adverse impacts on soil microbial activity should be considered. This review highlights the most common analytical methods to discover molecular interaction mechanisms between biochar and PTEs and future research areas required for the understanding of biochar-PTE interactions in polluted soil systems.
The issue of microplastic pollution emerged from the marine environment, but the terrestrial environment is estimated to receive annually 4-23 times more plastic wastes. Microplastic pollution in the ...soil environment has thus begun to elicit great concern. This review summarizes the observed effects of microplastic pollution on soil ecosystems as well as sorption and transport behaviors of microplastics in such environments. Microplastic pollution has been detected in various soils including agricultural/farmland, greenhouse, home garden, coastal, industrial, and floodplain soils. Microplastics affect soil physical and chemical properties, microbial and enzyme activities, and plant growth, and also pose adverse ecotoxicological effects to soil fauna. These effects depend on the concentration, size, and shape of microplastics, as well as soil texture. Microplastics are known to sorb organic and inorganic pollutants, possibly affecting the distribution of these substances in soil. Existing evidence demonstrates the negligible effect of microplastics on bioaccumulation of contaminants in soil fauna. The horizontal and vertical transport of microplastics can be facilitated by soil fauna. Pollutants associated with microplastics may disperse further following the transport of microplastics in soil. This review also highlights perspectives for future research on microplastics in soil.
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