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Wang F, Shi L, Zhang R, Xu W, Bo Y. Effects of nitrogen addition and Bothriochloa ischaemum and Lespedeza davurica mixture on plant chlorophyll fluorescence and community production in semi-arid grassland. FRONTIERS IN PLANT SCIENCE 2024; 15:1400309. [PMID: 38984159 PMCID: PMC11232416 DOI: 10.3389/fpls.2024.1400309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 06/06/2024] [Indexed: 07/11/2024]
Abstract
Background Grass-legume mixture can effectively improve productivity and stimulate overyielding in artificial grasslands, but may be N-limited in semi-arid regions. This study investigated the effects of N addition on chlorophyll fluorescence and production in the grass-legume mixtures community. Methods An N addition experiment was conducted in the Bothriochloa ischaemum and Lespedeza davurica mixture community, with seven mixture ratios (B0L10, B2L8, B4L6, B5L5, B6L4, B8L2, and B10L0) according to the sowing abundance of B.ischaemum and L.davurica and four N addition levels, N0, N25, N50, and N75 (0,25,50,75kgNhm-2 a-1), respectively. We analyzed the response of chlorophyll fluorescence parameters of the two species, the rapid light-response curves of chlorophyll fluorescence, as well as aboveground biomass (AGB) and overyielding. Results Our results showed that the two species showed different photosynthetic strategies, with L.davurica having significantly higher initial fluorescence (Fo), effective photochemical quantum yield of PSII (ΦPSII), and coefficient of photochemical fluorescence quenching (qP) than B. ischaemum, consisting with results of rapid light-response curves. N addition and mixture ratio both had significant effects on chlorophyll fluorescence and AGB (p<0.001). The ΦPSII and qP of L.davurica were significantly lowest in B5L5 and B6L4 under N addition, and the effect of N varied with mixture ratio. The photosynthetic efficiency of B. ischaemum was higher in mixture than in monoculture (B10L0), and ΦPSII was significantly higher in N50 than in N25 and N50 at mixture communities except at B5L5. The community AGB was significantly higher in mixture communities than in two monocultures and highest at B6L4. In the same mixture ratio, the AGB was highest under the N50. The overyielding effects were significantly highest under the N75 and B6L4 treatments, mainly attributed to L.davurica. The partial least squares path models demonstrated that adding N increased soil nutrient content, and complementary utilization by B.ischaemum and L.davurica increased the photosynthetic efficiency. However, as the different photosynthetic strategies of these two species, the effect on AGB was offset, and the mixture ratio's effects were larger than N. Our results proposed the B6L4 and N50 treatments were the optimal combination, with the highest AGB and overyielding, moderate grass-legume ratio, optimal community structure, and forage values.
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Affiliation(s)
- Fugang Wang
- College of Life Science, Yulin University, Yulin, China
| | - Lei Shi
- College of Life Science, Yulin University, Yulin, China
| | - Ruiyi Zhang
- College of Life Science, Yulin University, Yulin, China
| | - Weizhou Xu
- College of Life Science, Yulin University, Yulin, China
- Shaanxi Engineering Research Center of Forage Plants of the Loess Plateau, Yulin University, Yulin, Shaanxi, China
| | - Yaojun Bo
- College of Life Science, Yulin University, Yulin, China
- Shaanxi Engineering Research Center of Forage Plants of the Loess Plateau, Yulin University, Yulin, Shaanxi, China
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Yang Z, Li J, Xiao R, Zhang C, Ma X, Du G, Li G, Jiang L. Losses of low-germinating, slow-growing species prevent grassland composition recovery from nutrient amendment. GLOBAL CHANGE BIOLOGY 2024; 30:e17264. [PMID: 38556774 DOI: 10.1111/gcb.17264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 02/22/2024] [Accepted: 03/03/2024] [Indexed: 04/02/2024]
Abstract
Nutrient enrichment often alters the biomass and species composition of plant communities, but the extent to which these changes are reversible after the cessation of nutrient addition is not well-understood. Our 22-year experiment (15 years for nutrient addition and 7 years for recovery), conducted in an alpine meadow, showed that soil nitrogen concentration and pH recovered rapidly after cessation of nutrient addition. However, this was not accompanied by a full recovery of plant community composition. An incomplete recovery in plant diversity and a directional shift in species composition from grass dominance to forb dominance were observed 7 years after the nutrient addition ended. Strikingy, the historically dominant sedges with low germination rate and slow growth rate and nitrogen-fixing legumes with low germination rate were unable to re-establish after nutrient addition ceased. By contrast, rapid recovery of aboveground biomass was observed after nutrient cessation as the increase in forb biomass only partially compensated for the decline in grass biomass. These results indicate that anthropogenic nutrient input can have long-lasting effects on the structure, but not the soil chemistry and plant biomass, of grassland communities, and that the recovery of soil chemical properties and plant biomass does not necessarily guarantee the restoration of plant community structure. These findings have important implications for the management and recovery of grassland communities, many of which are experiencing alterations in resource input.
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Affiliation(s)
- Zhongling Yang
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, China
| | - Junyong Li
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, China
- Dabieshan National Observation and Research Field Station of Forest Ecosystem, Henan University, Kaifeng, China
| | - Rui Xiao
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, China
| | - Chunhui Zhang
- State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, China
| | - Xiaojun Ma
- School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Guozhen Du
- School of Life Sciences, Lanzhou University, Lanzhou, China
| | - Guoyong Li
- International Joint Research Laboratory for Global Change Ecology, School of Life Sciences, Henan University, Kaifeng, China
- Dabieshan National Observation and Research Field Station of Forest Ecosystem, Henan University, Kaifeng, China
| | - Lin Jiang
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia, USA
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He M, Barry KE, Soons MB, Allan E, Cappelli SL, Craven D, Doležal J, Isbell F, Lanta V, Lepš J, Liang M, Mason N, Palmborg C, Pichon NA, da Silveira Pontes L, Reich PB, Roscher C, Hautier Y. Cumulative nitrogen enrichment alters the drivers of grassland overyielding. Commun Biol 2024; 7:309. [PMID: 38467761 PMCID: PMC10928195 DOI: 10.1038/s42003-024-05999-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 03/01/2024] [Indexed: 03/13/2024] Open
Abstract
Effects of plant diversity on grassland productivity, or overyielding, are found to be robust to nutrient enrichment. However, the impact of cumulative nitrogen (N) addition (total N added over time) on overyielding and its drivers are underexplored. Synthesizing data from 15 multi-year grassland biodiversity experiments with N addition, we found that N addition decreases complementarity effects and increases selection effects proportionately, resulting in no overall change in overyielding regardless of N addition rate. However, we observed a convex relationship between overyielding and cumulative N addition, driven by a shift from complementarity to selection effects. This shift suggests diminishing positive interactions and an increasing contribution of a few dominant species with increasing N accumulation. Recognizing the importance of cumulative N addition is vital for understanding its impacts on grassland overyielding, contributing essential insights for biodiversity conservation and ecosystem resilience in the face of increasing N deposition.
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Affiliation(s)
- Miao He
- Ecology and Biodiversity group, Department of Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1479 Gortner Ave, St Paul, MN, 55108, USA.
| | - Kathryn E Barry
- Ecology and Biodiversity group, Department of Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Merel B Soons
- Ecology and Biodiversity group, Department of Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Eric Allan
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland
- Centre for Development and Environment CDE, University of Bern, Mittelstrasse 43, 3012, Bern, Switzerland
| | - Seraina L Cappelli
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1479 Gortner Ave, St Paul, MN, 55108, USA
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland
| | - Dylan Craven
- GEMA Center for Genomics, Ecology & Environment, Universidad Mayor, Camino La Pirámide, 5750, Huechuraba, Santiago, Chile
- Data Observatory Foundation, ANID Technology Center No. DO210001, Eliodoro Yáñez 2990, 7510277, Providencia, Santiago, Chile
| | - Jiří Doležal
- Department of Functional Ecology, Institute of Botany of the Czech Academy of Sciences, Zámek 1, 252 43, Průhonice, Czech Republic
- Department of Botany, Faculty of Science, University of South Bohemia, Na Zlaté stoce 1, 370 05, České Budějovice, Czech Republic
| | - Forest Isbell
- Department of Ecology, Evolution, and Behavior, University of Minnesota, 1479 Gortner Ave, St Paul, MN, 55108, USA
| | - Vojtěch Lanta
- Department of Functional Ecology, Institute of Botany of the Czech Academy of Sciences, Zámek 1, 252 43, Průhonice, Czech Republic
| | - Jan Lepš
- Department of Botany, Faculty of Science, University of South Bohemia, Na Zlaté stoce 1, 370 05, České Budějovice, Czech Republic
| | - Maowei Liang
- Cedar Creek Ecosystem Science Reserve, University of Minnesota, 2660 Fawn Lake Dr NE, East Bethel, MN, 55005, USA
| | - Norman Mason
- Landcare Research, Private Bag 3127, Hamilton, 3240, New Zealand
| | - Cecilia Palmborg
- Department of Crop production Ecology, Swedish University of Agricultural Sciences, 901 83, Umeå, Sweden
| | - Noémie A Pichon
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, 3013, Bern, Switzerland
- Swiss Federal Research Institute WSL, Zürcherstrasse 111, CH-8903, Birmensdorf, Switzerland
| | - Laíse da Silveira Pontes
- Rural Development Institute of Paraná - IAPAR-EMATER, Av. Euzébio de Queirós, s/n°, CP 129, CEP 84001-970, Ponta Grossa, PR, Brazil
| | - Peter B Reich
- Department of Forest Resources, University of Minnesota, 1479 Gortner Ave, St Paul, MN, 55108, USA
- Institute for Global Change Biology, and School for the Environment and Sustainability, University of Michigan, 440 Church Street, Ann Arbor, MI, 48109, USA
| | - Christiane Roscher
- UFZ, Helmholtz Centre for Environmental Research, Physiological Diversity, Permoserstrasse 15, 04318, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv), Puschstrasse 4, 04103, Leipzig, Germany
| | - Yann Hautier
- Ecology and Biodiversity group, Department of Biology, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
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Zhang M, Li X, Xing F, Li Z, Liu X, Li Y. Soil Microbial Legacy Overrides the Responses of a Dominant Grass and Nitrogen-Cycling Functional Microbes in Grassland Soil to Nitrogen Addition. PLANTS (BASEL, SWITZERLAND) 2022; 11:1305. [PMID: 35631730 PMCID: PMC9145027 DOI: 10.3390/plants11101305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/03/2022] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
Both atmospheric nitrogen (N) deposition and soil microbial legacy (SML) can affect plant performance, the activity of soil N-cycling functional microbes and the relative abundance of N-cycling functional genes (NCFGs). In the grassland vegetation successional process, how the interaction of SML and N deposition affects the performance of dominant grass and NCFGs remains unclear. Therefore, we planted Leymus chinensis, a dominant grass in the Songnen grassland, in the soil taken from the early, medium, late, and stable successional stages. We subjected the plants to soil sterilization and N addition treatments and measured the plant traits and NCFG abundances (i.e., nifH, AOB amoA, nirS, and nirK). Our results showed the biomass and ramet number of L. chinensis in sterilized soil were significantly higher than those in non-sterilized soil, indicating that SML negatively affects the growth of L. chinensis. However, N addition increased the plant biomass and the AOB amoA gene abundance only in sterilized soils, implying that SML overrode the N addition effects because SML buffered the effects of increasing soil N availability on NCFGs. Therefore, we emphasize the potential role of SML in assessing the effects of N deposition on dominant plant performance and NCFGs in the grassland vegetation succession.
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Affiliation(s)
- Minghui Zhang
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
| | - Xueli Li
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
| | - Fu Xing
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
| | - Zhuo Li
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
| | - Xiaowei Liu
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
| | - Yanan Li
- Key Laboratory of Vegetation Ecology, Ministry of Education, Jilin Songnen Grassland Ecosystem National Observation and Research Station, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China; (M.Z.); (X.L.); (Z.L.); (X.L.); (Y.L.)
- Jilin Provincial Key Laboratory of Ecological Restoration and Ecosystem Management, Northeast Normal University, Changchun 130024, China
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Estimating Carbon, Nitrogen, and Phosphorus Contents of West–East Grassland Transect in Inner Mongolia Based on Sentinel-2 and Meteorological Data. REMOTE SENSING 2022. [DOI: 10.3390/rs14020242] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Estimating the carbon (C), nitrogen (N), and phosphorus (P) contents of a large-span grassland transect is essential for evaluating ecosystem functioning and monitoring biogeochemical cycles. However, the field measurements are scattered, such that they cannot indicate the continuous gradient change in the grassland transect. Although remote sensing methods have been applied for the estimation of nutrient elements at the local scale in recent years, few studies have considered the effective estimation of C, N, and P contents over large-span grassland transects with complex environment including a variety of grassland types (i.e., meadow, typical grassland, and desert grassland). In this paper, an information enhancement algorithm (involving spectral enhancement, regional enhancement, and feature enhancement) is used to extract the weak information related to C, N, and P. First, the spectral simulation algorithm is used to enhance the spectral information of Sentinel-2 imagery. Then, the enhanced spectra and meteorological data are fused to express regional characteristics and the fractional differential (FD) algorithm is used to extract sensitive spectral features related to C, N, and P, in order to construct a partial least-squares regression (PLSR) model. Finally, the C, N, and P contents are estimated over a West–East grassland transect in Inner Mongolia, China. The results demonstrate that: (i) the contents of C, N, and P in large-span transects can be effectively estimated through use of the information enhancement method involving spectral enhancement, regional feature enhancement, and information enhancement, for which the estimation accuracies (R2) were 0.88, 0.78, and 0.85, respectively. Compared with the estimation results of raw Sentinel-2 imagery, the RMSE was reduced by 3.42 g/m2, 0.14 g/m2, and 13.73 mg/m2, respectively; and (ii) the continuous change trend and spatial distribution characteristics of C, N, and P contents in the west–east transect of the Inner Mongolia Plateau were obtained, which showed decreasing trends in C, N, and P contents from east to west and the characteristics of meadow > typical grassland > desert grassland. Thus, the information enhancement algorithm can help to improve estimates of C, N, and P contents when considering large-span grassland transects.
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Shi W, Du M, Ye C, Zhang Q. Divergent effects of hydrological alteration and nutrient addition on greenhouse gas emissions in the water level fluctuation zone of the Three Gorges Reservoir, China. WATER RESEARCH 2021; 201:117308. [PMID: 34102598 DOI: 10.1016/j.watres.2021.117308] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Changes in global rainfall patterns and construction of artificial dams have led to widespread alteration of hydrological processes in riparian ecosystems. At the same time, many riparian ecosystems, such as those associated with the Yangtze, are being subjected to enhanced inputs of nitrogen (N) and phosphorus (P) due to intensified agricultural activity in surrounding uplands. Together, these environmental changes may alter the magnitude and direction of greenhouse gasses (GHGs) fluxes from riparian soils. We conducted an in situ experiment combined with quantitative PCR approach (qPCR) to elucidate the effects of hydrological alterations (continuous flooding (CF), periodic flooding (PF), and no flooding (NF)) and nutrient addition (N addition (urea, 100 kg N ha-1 y-1), P addition (P2O5, 20 kg ha-1y-1), N + P addition, and control (CK)) on three major GHGs including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes as well as the underlying mechanisms. Our results showed that hydrological alterations greatly affected GHGs emissions, possibly by altering soil moisture, soil organic C, and C:N ratios. The CF, with higher soil moisture and lower C:N ratio, increased CH4 emissions 13-fold and reduced CO2 and N2O emissions by 37.3% and 72.2% averaged over the growing seasons compared with no flooding. PF enhanced CH4 emissions 5.7-fold and decreased N2O emissions by 69.0% in comparison with no flooding. Nutrient additions had no significant effect on CO2 or CH4 flux, but P addition significantly lowered N2O flux. Interactions between hydrological alterations and nutrient additions were not detected for any GHGs. As a result, hydrological alterations and nutrient additions affected the global warming potential (GWP) of growing season GHG budgets on a 100-year time horizon, mainly by changing the CO2 emissions. CF reduced GWP from 597 to 439 g CO2-eq m-2, and N + P addition enhanced GWP from 489 to 625 g CO2-eq m-2. The qPCR analysis revealed that decreased CH4 oxidation potential may lead to the enrichment of CH4 emissions under the hydrological alterations, and reduced nitrification and denitrification potential contributed to the reduction of N2O fluxes under all the treatments. Our study indicates that continuous flooding could curb the contribution of riparian GHGs fluxes to global warming but that the combination of N and P additions may increase the greenhouse effect mainly by regulating the CO2 emissions of growing season in riparian ecosystem.
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Affiliation(s)
- Wenjun Shi
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan 430074, PR China; Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China; The University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Ming Du
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan 430074, PR China; Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China
| | - Chen Ye
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan 430074, PR China; Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China.
| | - Quanfa Zhang
- Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden of the Chinese Academy of Sciences, Wuhan 430074, PR China; Center for Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, PR China.
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Abstract
Global deposits of concentrated phosphates, which are a necessary source for the production of phosphate fertilizers, are limited. These reserves keep getting thinner, and every day, large amounts of phosphorus end up in watercourses. In this study, we verified that modified biochar (saturated with FeCl3 solution and then neutralized with NaOH solution) can adsorb significant amounts of phosphorus from wastewater. Moreover, the agrochemical qualities of sludge water from a municipal wastewater treatment plant, struvite, phosphorus-saturated biochar, and iron(III) phosphate from a reused biochar filter were tested in this study. We determined the amount of mobile phosphorus as well as the amount of extractable phosphorus and its five fractions. It was found that modified biochar can hold one-third of the phosphorus amount contained in the commonly used agricultural fertilizer simple superphosphate (1 × 105 g of modified biochar captures up to 2.79 × 103 g of P). Moreover, plants can more easily access phosphorus biochar fractions than struvite, which is formed spontaneously during sludge management. The results of this research prove that the proposed method of recycling phosphorus from wastewater can be applied in technological practice.
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