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The accumulation of arsenic (As) in rice (Oryza sativa L.) grain poses a significant health concern in Bangladesh. To address this, we investigated the efficacy of various organic amendments and phytoremediation techniques in reducing As buildup in O. sativa. We evaluated the impact of five doses of biochar (BC; BC0.1: 0.1%, BC0.28: 0.28%, BC0.55: 0.55%, BC0.82: 0.82% and BC1.0: 1.0%, w/w), vermicompost (VC; VC1.0: 1.0%, VC1.8: 1.8%, VC3.0: 3.0%, VC4.2: 4.2% and VC5.0: 5.0%, w/w), and floating duckweed (DW; DW100: 100, DW160: 160, DW250: 250, DW340: 340 and DW400: 400 g m- 2) on O. sativa cultivated in As-contaminated soil. Employing a three-factor five-level central composite design and response surface methodology (RSM), we optimized the application rates of BC-VC-DW. Our findings revealed that As contamination in the soil negatively impacted O. sativa growth. However, the addition of BC, VC, and DW significantly enhanced plant morphological parameters, SPAD value, and grain yield per pot. Notably, a combination of moderate BC-DW and high VC (BC0.55VC5DW250) increased grain yield by 44.4% compared to the control (BC0VC0DW0). As contamination increased root, straw, and grain As levels, and oxidative stress in O. sativa leaves. However, treatment BC0.82VC4.2DW340 significantly reduced grain As (G-As) by 56%, leaf hydrogen peroxide by 71%, and malondialdehyde by 50% compared to the control. Lower doses of BC-VC-DW (BC0.28VC1.8DW160) increased antioxidant enzyme activities, while moderate to high doses resulted in a decline in these activities. Bioconcentration and translocation factors below 1 indicated limited As uptake and translocation in plant tissues. Through RSM optimization, we determined that optimal doses of BC (0.76%), VC (4.62%), and DW (290.0 g m- 2) could maximize grain yield (32.96 g pot- 1, 44% higher than control) and minimize G-As content (0.189 mg kg- 1, 54% lower than control). These findings underscore effective strategies for enhancing yield and reducing As accumulation in grains from contaminated areas, thereby ensuring agricultural productivity, human health, and long-term sustainability. Overall, our study contributes to safer food production and improved public health in As-affected regions.
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Arsénico , Biodegradación Ambiental , Carbón Orgánico , Oryza , Contaminantes del Suelo , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Arsénico/metabolismo , Contaminantes del Suelo/metabolismo , Compostaje/métodos , Araceae/metabolismo , Araceae/efectos de los fármacos , Araceae/crecimiento & desarrollo , Suelo/químicaRESUMEN
Microplastic (MP) pollution in terrestrial ecosystems is gaining attention, but there is limited research on its effects on leafy vegetables when combined with heavy metals. This study examines the impact of three MP types-polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS)-at concentrations of 0.02, 0.05, and 0.1% w/w, along with cadmium (Cd) and biochar (B), on germination, growth, nutrient absorption, and heavy metal uptake in red amaranth (Amaranthus tricolor L.). We found that different MP types and concentrations did not negatively affect germination parameters like germination rate, relative germination rate, germination vigor, relative germination vigor, and germination speed. However, they increased phytotoxicity and decreased stress tolerance compared to an untreated control (CK1). The presence of MPs, particularly the PS type, reduced phosphorus and potassium uptake while enhancing Cd uptake. For example, treatments PS0.02CdB, PS0.05CdB, and PS0.1CdB increased Cd content in A. tricolor seedlings by 158%, 126%, and 44%, respectively, compared to the treatment CdB (CK2). Additionally, MP contamination led to reduced plant height, leaf dry matter content, and fresh and dry weights, indicating adverse effects on plant growth. Moreover, the presence of MPs increased bioconcentration factors and translocation factors for Cd, suggesting that MPs might act as carriers for heavy metal absorption in plants. On the positive side, the addition of biochar improved several root parameters, including root length, volume, surface area, and the number of root tips in the presence of MPs, indicating potential benefits for plant growth. Our study shows that the combination of MPs and Cd reduces plant growth and increases the risk of heavy metal contamination in food crops. Further research is needed to understand how different MP types and concentrations affect various plant species, which will aid in developing targeted mitigation strategies and in exploring the mechanisms through which MPs impact plant growth and heavy metal uptake. Finally, investigating the potential of biochar application in conjunction with other amendments in mitigating these effects could be key to addressing MP and heavy metal contamination in agricultural systems.
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Amaranthus , Cadmio , Carbón Orgánico , Microplásticos , Amaranthus/efectos de los fármacos , Amaranthus/crecimiento & desarrollo , Amaranthus/metabolismo , Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Germinación/efectos de los fármacos , Nutrientes/metabolismo , Plantones/crecimiento & desarrollo , Plantones/efectos de los fármacos , Plantones/metabolismoRESUMEN
To improve our understanding of how coal mining areas can be re-vegetated and ecosystem function restored, we examined the potential effects of five water (W) regimes (40, 50, 60, 70 and 80% of field capacity), five nitrogen (N) (0, 24, 60, 96 and 120 mg kgâ1 soil) and five phosphorus (P) fertilizer doses (0, 36, 90, 144 and 180 mg kgâ1 soil), which control the growth and development of Elaeagnus angustifolia under adverse environmental conditions. To optimize the W-N-P application rate, three factors and five levels of central composite design along with an optimization technique named response surface methodology were utilized. Here we provide data on root-shoot biomass ratio, leaf dry matter content, stomatal conductance, chlorophyll (Chl) a, Chl b, membrane stability index and soluble protein content of E. angustifolia. The data described in this article are available in Mendeley Data, DOI: 10.17632/2vfbrdxyf2.2[1]. These data could be used to evaluate the improvement in growth performance of E. angustifolia subjected to various regimes of W, N and P. This dataset showed that E. angustifolia grew optimally in coal-mine spoils when irrigated at 66% of field capacity and supplemented with 74.0 mg N and 36.0 mg P kgâ1 soil. This could considerably help the success of revegetation in coal-mined degraded arid areas where W is scarce. This article contains data complementary to the main research entitled "Fine-tuning of soil water and nutrient fertilizer levels for the ecological restoration of coal-mined spoils using Elaeagnus angustifolia" in the Journal of Environmental Management (Roy et al., 2020).
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Surface mining is a critical anthropogenic activity that significantly alters the ecosystem, while the use of appropriate revegetation techniques can be considered an important and feasible strategy in the way to improve the ecosystem services of degraded land. In the present study, we carried out a pot experiment to investigate the effects of three different variables on morpho-physiological and biochemical parameters of Onobrychis viciifolia to assess the capability of this species to be used for restoration purposes. Specifically, the variables studied were: (a) water (W) regime, working at five values as regards field capacity (FC) (i.e., 80% FC = highest, 72% FC = high, 60% FC = moderate, 48% FC = low, and 40% FC = very-low dose); and (b) rates of cattle manure compost (CMC) and wood biochar (BC) (weight/weight ratio), working at five rates (i.e., 4.0% = highest, 3.2% = high, 2.0% = moderate, 0.8% = low, and 0% = either no-CMC or no-BC dose). In addition, soil physical-chemical properties and enzyme activities were also investigated at the end of the experimental period. It was found that morphological growth attributes such as plant height, maximum root length, and dry biomass significantly increased with W, CMC and BC applications. Compared to control, moderate-to-high W, CMC and BC doses (W80CMC2BC2) increased net photosynthesis rate (by 42%), stomatal conductance (by 50%), transpiration rate (by 29%), water use efficiency (by 10%), chlorophyll contents (by 73%), carotenoid content (by 81%), leaf relative water content (by 33%) and leaf membrane stability index (by 30%). Under low-W content, the application of CMC and BC enhanced osmotic adjustments by increasing the content of soluble sugar and the activities of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase, decreasing the oxidative stress, as verified by low levels of hydrogen peroxide, superoxide anion, malondialdehyde and proline contents in leaf tissues. Moreover, application of W, CMC and BC significantly improved soil water holding capacity, available nitrogen, phosphorus and potassium, urease and catalase activities, which facilitate plant growth. These results would aid in designing an appropriate strategy for achieving a successful revegetation of O. viciifolia, providing optimum doses of W (64% field capacity), CMC (2.4%) and BC (1.7%), with the final aim of reaching ecological restoration in arid degraded lands.
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Compostaje , Estiércol , Animales , Bovinos , Carbón Orgánico , Carbón Mineral , Deshidratación , Suplementos Dietéticos , Ecosistema , Suelo/químicaRESUMEN
Ecological restoration of coal mine degraded soils across arid and semi-arid environments worldwide remains particularly challenging. We used a combination of greenhouse and field experiments to assess the potential role of a woody species, Ulmus pumila, in the restoration of degraded soils associated with coal-mining activities in the northwest China. We investigated how various combinations of water-nitrogen-phosphorus (W-N-P) resources affect multiple growth parameters in U. pumila. We found that several plant growth traits significantly improved with W-N applications, regardless of P inputs. Moderate-to-highest W-N-P doses increased net photosynthesis and transpiration rates, water use efficiency, stomatal conductance, chlorophyll and carotenoid contents under greenhouse conditions. A combination of high W together with low N-P applications led to high relative water content and net photosynthetic rates under field conditions. Increasing of N-P doses under W-shortage condition, aided U. pumila to enhance osmotic adjustments by increasing contents of proline and soluble sugar and also boost the activity of superoxide dismutase, peroxidase and catalase in leaf tissues to reduce accumulation of reactive oxygen species and malondialdehyde content in all conditions of greenhouse and field. Our study is the first to assess the optimum W-N-P resources in U. pumila and demonstrate that optimum growth performance could be obtained under W supplements corresponding to 90 mm year-1, N and P at 110 and 45 kg ha-1, respectively, under field condition. These findings can have far reaching implications for vegetation restoration of degraded areas associated with coal-mining activities across arid and semi-arid regions worldwide.
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Carbón Mineral , Agua , Nutrientes , Suelo , MaderaRESUMEN
Coal mining activities are responsible for significant land degradation and often long-term irreversible effects on ecosystem functioning. To better understand how coal mined sites could be re-vegetated and ecosystem functioning restored, we address the role of the signalling hormone melatonin, which controls plant growth and development under adverse environmental conditions. We assessed the effects of exogenous melatonin on the plant species Althaea rosea by measuring morphological growth attributes, photosynthetic efficiency, reactive oxygen species (ROS)-induced oxidative damage and antioxidant defence developed by the seedlings when grown on coal-mined spoils under various water regimes. Water deficit and negative effects of coal mine spoils significantly decreased morphological growth attributes (i.e. plant height, root length and dry biomass), gas-exchange traits (i.e. net photosynthesis rate, inter intercellular concentration of CO2, transpiration rate, stomatal conductance and water use efficiency) and photosynthetic pigments (chlorophyll and carotenoid contents) by increasing the ROS-induce oxidative damage and decreasing antioxidant enzyme activities of A. rosea seedlings. However, melatonin applications increased photosynthetic performance and antioxidant enzyme activities and decreased hydrogen peroxide and malondialdehyde contents and ultimately improved growth performance of A. rosea in coal-mined spoils. Overall, our findings show how the application of optimum water (63.0 %field capacity equivalent to 1.67 mm day-1) and melatonin (153.0 µM dose) significantly improves the re-vegetation of coal-mined spoils with A. rosea. Our study provides new insight into melatonin-mediated water stress tolerance in A. rosea grown on coal-mined spoils, and this strategy could be implemented in re-vegetation programmes of coal mine-degraded areas under arid and semiarid conditions of the north-western part of China and perhaps across other arid areas worldwide.
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Althaea , Malvaceae , Melatonina , Althaea/metabolismo , Antioxidantes/metabolismo , Carbón Mineral , Deshidratación/metabolismo , Ecosistema , Melatonina/metabolismo , Melatonina/farmacología , Estrés Oxidativo , Fotosíntesis , Especies Reactivas de Oxígeno/metabolismo , PlantonesRESUMEN
This study analyzes the effects of credit constraints on technical efficiency of Boro rice growers in the district of Pabna in Bangladesh. Using a simple random sampling technique, the data was collected from 570 Boro rice growers from the Pabna district of Bangladesh. Before conducting a field survey, a theoretical model was designed to identify credit-constrained and non-constrained rice growers. We have analyzed the collected data in two phases: first, we investigated the technical efficiency of Boro rice growers using the stochastic frontier model (SFA); and second, we used an inefficiency effect model to estimate the influence of credit constraints on technical efficiency. Findings indicate that credit-constrained rice growers (CCRG) are 6.7% less technically efficient than credit non-constrained rice growers (CNRG). Findings further indicate that the education level of the household head, family size, certified seed, sowing time, access to extension services, off-farm income, and household savings have significant effects on the technical efficiency of both groups of rice growers. Furthermore, credit size has a significantly positive impact, whereas the interest rate imposed on the principal amount has a significantly negative impact.
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Oryza , Bangladesh , Eficiencia , GranjasRESUMEN
Accomplishing unremitting favorable health outcomes, especially reducing maternal mortality, remains a challenge for South Asian countries. This study explores the relationship between health expenditure and maternal mortality by using data set consisting of 18 years from 2000 to 2017. Fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) models were employed for the empirical analysis. The outcomes revealed that a 1% rise in health expenditure increased the maternal mortality rate by 1.95% in the case of FMOLS estimator and 0.16% in the case of DOLS estimator. This reflects that the prevailing health care system is not adequate for reducing maternal mortality. Moreover, the meager system and the priorities established by an elitist system in which the powerless and poor are not considered may also lead to worsen the situation. In addition, the study also added population, economic growth, sanitation, and clean fuel technology in the empirical model. The findings revealed that population growth has a significant long-term effect on maternal mortality-an increase of 40% in the case of FMOLS and 10% in the case of DOLS-and infers that an increase in population growth has also dampened efforts towards reducing maternal mortality in the South Asian panel. Further, the results in the case of economic growth, sanitation, and clean fuel technologies showed significant long-term negative effects on maternal mortality by 94%, 7.2%, and 11%, respectively, in the case of the FMOLS estimator, and 18%, 1.9%, and 5%, respectively, in the case of the DOLS estimator. The findings imply that GDP and access to sanitation and clean fuel technologies are more nuanced in declining maternal mortality. In conclusion, the verdict shows that policymakers should formulate policies considering the fundamental South Asian aspects warranted to reduce maternal mortality.
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Gastos en Salud , Mortalidad Materna , Dióxido de Carbono , Desarrollo Económico , Política de SaludRESUMEN
Women's empowerment has a great influence on health, nutrition, education, and the overall well-being of societies as well as of the children and households. This study investigates the effect of women's empowerment on poverty reduction and focuses on household deprivation, in terms of education, health, and standard of living. Primary data was collected from 914 married women from rural areas of Bangladesh using a well-structured questionnaire and a random sampling technique. Descriptive statistics, logistic regression, and ordinary least squares models were used in this study. The results indicate that increased women's access to education, asset ownership, decision-making power on children's health and education, and access to medical facilities, have caused a significant decline in income poverty and multidimensional poverty. However, gender violence, taking resources against women's will, and preventing women from working outside, have caused a considerable decline in per capita income and an increase in income poverty and multidimensional poverty. Overall, it is found that women's empowerment has a great impact on the reduction of income poverty and multidimensional poverty in society. The findings of the study can assist and guide policymakers to initiate appropriate strategies for women's empowerment to reducing poverty in Bangladesh while making progress towards other social and developmental goals.
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Renta , Pobreza , Bangladesh , Niño , Escolaridad , Femenino , Humanos , Factores Socioeconómicos , Derechos de la MujerRESUMEN
Ecosystem degradation as a result of coal mining is a common phenomenon in various regions of the world, especially in arid and semi-arid zones. The implementation of appropriate revegetation techniques can be considered crucial to restore these degraded areas. In this regard, the additions of spent mushroom compost (SMC) and wood biochar (WB) to infertile and degraded soils have been reported to enhance soil fertility and plant growth under water (W) deficit conditions. However, the combined application of W, SMC and WB to coal mine degraded soils, to promote Althaea rosea growth and facilitate subsequent restoration, has not been explored yet. Hence, in the current study a pot experiment was carried out by growing A. rosea on coal mine spoils to assess the influence of different doses of W, SMC and WB on its morpho-physiological and biochemical growth responses. The results indicated that several plant growth traits like plant height, root length and dry biomass significantly improved with moderate W-SMC-WB doses. In addition, the simultaneous application of W-SMC-WB caused a significant decrease in hydrogen peroxide (H2O2) (by 7-56%), superoxide anion (O2ââ) (by 14-51%), malondialdehyde (MDA) (by 23-46%) and proline (Pro) contents (by 23-66%), as well as an increase in relative water content (by 10-27%), membrane stability index (by 2-24%), net photosynthesis rate (by 40-99%), total chlorophylls (by 43-113%) and carotenoids (by 31-115%), as compared to the control treatment. The addition of SMC and WB under low-W regime enhanced leaf water use efficiency, and soluble sugar content, also boosting the activity of superoxide dismutase, catalase, peroxidase and ascorbate peroxidase in leaf tissues, thus reducing the oxidative stress, as proved by low levels of H2O2, O2ââ, MDA and Pro contents. Finest growth performance under optimum doses of W (60% field capacity), SMC (1.4%) and WB (0.8%) suggest that revegetation of A. rosea with the recommended W-SMC-WB doses would be a suitable and eco-friendly approach for ecological restoration in arid degraded areas.
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Agaricales , Althaea , Compostaje , Carbón Orgánico , Carbón Mineral , Sequías , Ecosistema , Peróxido de Hidrógeno , Suelo , Agua , MaderaRESUMEN
Global discourses have advocated women's empowerment as a means to reduce their own's food insecurity, which is also key development challenges in Bangladesh. However, little empirical research has conducted on this issue, especially in the rural area of Bangladesh. Therefore, the present study was conducted to examine the relationship of six domains of women's empowerment with their food security in rural Bangladesh using a partial least square structural equation modelling approach. Our empirical analysis indicates that women's accesses to their legal and familial rights and decision-making roles in households increase their bargaining power over the utilization of resources and to choices of food which significantly and negatively decrease their food insecurity. Moreover, information and communication technologies and infrastructure facilities also negatively and significantly associated with women's food insecurity. However, women's leadership has a negative but not significant effect on their food insecurity, as low self-esteem rural women feel no ease in publicly addressing their inequalities. By understanding family composition from women's perceptions, the results from our research can assist policymakers to develop more suitable strategies to enhance the empowerment status of rural women and reduce their food insecurity.
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Seguridad Alimentaria , Población Rural , Bangladesh , Composición Familiar , Femenino , Alimentos , HumanosRESUMEN
BACKGROUND: Education institutions promptly implemented a set of steps to prevent the spread of COVID-19 among international Chinese students, such as restrictive physical exercise, mask wear, daily health reporting, etc. Success of such behavioral change campaigns largely depends on awareness building, satisfaction and trust on the authorities. The purpose of this current study is to assess the preventive, supportive and awareness-building steps taken during the COVID-19 pandemic for international students in China, that will be useful for planning such a behavioral change campaign in the potential pandemic situation in other parts of the world. METHODS: We conducted an online-based e-questionnaire survey among 467 international students in China through WeChat. The data collection duration was from February 20, 2020 to March 10, 2020 and we focused on their level of awareness, satisfaction, and trust in authorities regarding pandemic measures. Simple bivariate statistics was used to describe the background characteristics of the respondents along with adoption of the partial least squares-structural equation modeling (PLS-SEM) as the final model to demonstrate the relationship between the variables. RESULTS: In our study, the leading group of the respondents were within 31 to 35 years' age group (39.82%), male (61.88%), living single (58.24%) and doctoral level students (39.8%). The preventive and supportive measures taken by students and/or provided by the respective institution or authorities were positively related to students' satisfaction and had an acceptable strength (ß = 0.611, t = 9.679, p < 0.001). The trust gained in authorities also showed an acceptable strength (ß = 0.381, t = 5.653, p < 0.001) with a positive direction. Again, the personnel awareness building related to both students' satisfaction (ß = 0.295, t = 2.719, p < 0.001) and trust gain (ß = 0.131, t = 1.986, p < 0.05) in authorities had a positive and acceptable intensity. Therefore, our study clearly demonstrates the great impact of preventive and supportive measures in the development of students' satisfaction (R2 = 0.507 indicating moderate relationship). The satisfied students possessed a strong influence which eventually helped in building sufficient trust on their institutions (R2 = 0.797 indicating above substantial relationship). CONCLUSIONS: The worldwide student group is one of the most affected and vulnerable communities in this situation. So, there is a profound ground of research on how different states or authorities handle such situation. In this study, we have depicted the types and magnitude of care taken by Chinese government and educational institutions towards international students to relieve the panic of pandemic situation. Further research and such initiatives should be taken in to consideration for future emerging conditions.
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Concienciación , COVID-19/psicología , Conocimientos, Actitudes y Práctica en Salud , Satisfacción Personal , Estudiantes/psicología , Adulto , China , Femenino , Humanos , Internacionalidad , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Modelos Teóricos , Servicios Preventivos de Salud/estadística & datos numéricos , Grupos de Autoayuda/estadística & datos numéricos , Adulto JovenRESUMEN
Surface mining is a critical anthropogenic activity that significantly alters the ecosystem. Revegetation practices are largely utilized to compensate for these detrimental impacts of surface mining. In this study, we investigated the effects of five water (W) regimes [W40: 40%, W48: 48%, W60: 60%, W72: 72%, and W80: 80% of field capacity (FC)], five nitrogen (N) (N0: 0, N24: 24, N60: 60, N96: 96, and N120: 120 mg kg-1 soil), and five phosphorus (P) fertilizer doses (P0: 0, P36: 36, P90: 90, P144: 144, and P180: 180 mg kg-1 soil) on morpho-physiological and biochemical parameters of Ammopiptanthus mongolicus plants to assess the capability of this species to be used for restoration purposes. The results showed that under low W-N resources, A. mongolicus exhibited poor growth performance (i.e., reduced plant height, stem diameter, and dry biomass) in coal-degraded spoils, indicating that A. mongolicus exhibited successful adaptive mechanisms by reducing its biomass production to survive long in environmental stress conditions. Compared with control, moderate to high W and N-P application rates greatly enhanced the net photosynthesis rates, transpiration rates, water-use efficiency, chlorophyll (Chl) a, Chl b, total Chl, and carotenoid contents. Under low-W content, the N-P fertilization enhanced the contents of proline and soluble sugar, as well as the activities of superoxide dismutase, catalase, and peroxidase in leaf tissues, reducing the oxidative stress. Changes in plant growth and metabolism in W-shortage conditions supplied with N-P fertilization may be an adaptive strategy that is essential for its conservation and restoration in the desert ecosystem. The best growth performance was observed in plants under W supplements corresponding to 70% of FC and N and P doses of 33 and 36 mg kg-1 soil, respectively. Our results provide useful information for revegetation and ecological restoration in coal-degraded and arid-degraded lands in the world using endangered species A. mongolicus.
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Coal mining activities remain of great environmental concern because of several negative impacts on soil ecosystems. Appropriate revegetation interventions of coal-spoiled lands can provide environmental management solutions to restore soil degraded ecosystems. The present study addressed the potential of the pioneer woody species, Elaeagnus angustifolia, in the restoration of coal-mined spoils under a range of different water (W) levels and nitrogen (N) and phosphorus (P) applications. Our results show how moderate applications of N (N60 = 60 mg N kg-1 soil) and P (P90 = 90 mg P kg-1 soil) fertilizers led either to maximum or minimum growth performance of E. angustifolia depending on whether W was applied at very high (W80 = 80% field capacity) or very low (W40 = 40% field capacity) levels suggesting that W was the main limiting factor for plant growth. Very low-W regime (W40N60P90) also caused significant reduction of photosynthetic parameters, including net photosynthetic rate, transpiration rate and water use efficiency. The combination of high W-N doses with low P doses (W70N96P36) positively influenced gas-exchange parameters, chlorophyll and carotenoid contents. Seedlings treated with low-W and -N doses (W50N24P144) showed highest increases in malondialdehyde content and lowest levels of relative water content (RWC). Decreases in malondialdehyde content and increases in RWC were observed following a gradual increment of W and N doses, indicating that high W and N doses contributed to drought tolerance of E. angustifolia by protecting cell membranes and increasing water status. Low-W and -N applications considerably increased the activities of antioxidant enzymes (superoxide dismutase, catalase, and peroxidase) and the contents of proline and soluble sugars, suggesting that E. angustifolia developed defensive strategies to avoid damage induced by water scarcity. Results from heatmap and principal component analyses confirmed that W and N were the main clustering factors, and both N and P performed well at high-W dose. The optimum growth performance of E. angustifolia was found under a combination of W level at 66.0% of field capacity, N dose of 74.0 mg kg-1 soil, and P dose of 36.0 mg kg-1 soil. Our findings demonstrate how optimum growth performance of E. angustifolia can be achieved by fine-tuning doses of W, N, and P resources, and how this in turn could greatly support the ecological restoration of coal-mined degraded environments.
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Elaeagnaceae , Suelo , Carbón Mineral , Ecosistema , Fertilizantes , Nutrientes , AguaRESUMEN
BACKGROUND: Water availability and nutrient-status of soils play crucial roles in seedling establishment and plant survival in coal-spoiled areas worldwide. Restoration of spoils pertains to the application of proper doses of nutrients and water, and selection of particular plant species for efficient revegetation. This study aimed at examining the potential effects of different combinations of soil-water and fertilizers (nitrogen, N and phosphorus, P) on morpho-physiological and biochemical attributes of Amorpha fruticosa grown in coal-mined spoils. Three factors five-level central-composite-design with optimization technique response surface methodology (rsm) was used to optimize water irrigation and fertilizer application strategies. RESULTS: Our results revealed a strong correlation between experimental data and predicted values developed from the rsm model. The best responses of A. fruticosa in terms of plant height, stem diameter, root length, and dry biomass were observed under a high-water regime. Low-water regime caused a notable reduction in growth-associated parameters, and fertilization with either N or P did not show positive effects on those parameters, indicating that soil-water was the most influential factor for growth performance. Leaf water potential, gas-exchange parameters, and chlorophyll content significantly increased under high levels of soil-water, N and P, suggesting a synergistic effect of these factors for the improvement of photosynthesis-related parameters. At low soil-water contents and N-P fertilizer application levels, enhanced accumulation of malondialdehyde and proline indicated that A. fruticosa suffered from oxidative and osmotic stresses. Amorpha fruticosa also responded to oxidative stress by accelerating the activities of superoxide dismutase, catalase, and peroxidase. The effects of both fertilizers relied on soil-water, and fertilization was most effective under well-watered conditions. The maximum growth of A. fruticosa was observed under the combination of soil-water, N-dose and P-dose at 76% field capacity, 52.0 mg kg- 1 and 49.0 mg kg- 1, respectively. CONCLUSION: Our results demonstrate that rsm effectively designed appropriate doses of water and N-P fertilizer to restore coal-spoiled soils. Furthermore, A. fruticosa responded to low-water and fertilizer-shortage by upregulating defensive mechanism to avoid damage induced by such deficiencies. Finally, our findings provide effective strategies for revegetation of coal-contaminated spoils with A. fruticosa using appropriate doses of water and N-P fertilizers.