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Effect of a thermal power plant waste fly ash on leguminous and non-leguminous leafy vegetables in extracting maximum benefits from P and K fertilization
2015
Inam, Akhtar | Sahay, Seema
Although the Indian population is largely vegetarian, not much attention has been given to the cultivation of vegetables, as compared to other crops like cereals, pulses and oil seeds. Therefore, the present study was conducted on two leafy vegetables, spinach (Spanacia oleracea L.) and methi (Trigonella foenum graecum L.) commonly grown in Aligarh, as the two popular vegetables of Indian diet. The study was conducted for two successive years and during the first year, phosphorus and fly ash interactions with a uniform dose of nitrogen and potassium on both vegetables was observed. During the second year, while keeping nitrogen and phosphorus uniform, potassium and fly ash combinations were studied again with both vegetables, to determine the optimum dose of inorganic fertilizers and fly ash combination. It was observed that fly ash applied at the rate of 15 t ha-1 along with N40P15K20, proved optimum for spinach while in the case of methi, N20P30K40 + FA10 was sufficient. Therefore, both vegetables can safely be grown with 10 to 15 t ha-1 of fly ash and a comparatively lower quantity of NPK.
显示更多 [+] 显示较少 [-]Forest decline and soil nutritional problems in Pacific areas.
1990
Mueller Dombois D.
Lanscape control on diffuse pollution : a critical review on some investigations on phosphorus – retaining landscape features
2011
Dorioz , Jean Marcel (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques) | Gascuel-Odoux , Chantal (INRA , Rennes (France). UMR 1069 Sol Agro et hydrosystème Spatialisation) | Merot , Philippe (INRA , Rennes (France). UMR 1069 Sol Agro et hydrosystème Spatialisation) | Trevisan , Dominique (INRA , Thonon-Les-Bains (France). UMR 0042 Centre Alpin de Recherche sur les Réseaux Trophiques des Ecosystèmes limniques)
This text focuses on the identification, efficiencies, classification and management of landscape features having a potential buffer function regarding diffuse phosphorus, because of their specific structure (vegetation-soil) and of their location at the interface between sources (farm infrastructures, emitting fields…) and surface water bodies. These buffers are very diverse and correspond to natural landscape features (wetlands, riparian areas…) as well as manmade structures (constructed buffer strips or intermediate cases such as field margins, hedgerows). Their role and efficiency depends on the local factors controlling the retention processes (internal organisation and properties of the buffer), on the position within the watershed, and on the landscape context which reciprocally determines the overall buffer capacity of a watershed. On that basis, we recognize the diversity of the buffers in structure and functioning and thus in the way they attenuate the signal, their limitations (sustainability, side effects) and their hierarchic organisation at the watershed scale.
显示更多 [+] 显示较少 [-]A phospho-compost biological-based approach increases phosphate rock agronomic efficiency in faba bean as compared to chemical and physical treatments.
2022
Chtouki, Mohamed | Bargaz, Adnane | Lyamlouli, Karim | Oukarroum, Abdallah | Zeroual, Youssef
peer reviewed | Under arid and semi-arid conditions, direct application of phosphate rock (PR) as a source of phosphorus (P) for crop production is likely influenced by agricultural practices and soil properties. Different approaches could be used to improve the agronomic efficiency of low-grade PR over a wider range of soils and crops. In this study, biological, physical, and chemical treatments of low-grade Moroccan PR were investigated and compared through agronomic trials on faba bean grown under alkaline soil conditions. The physical treatment was based on blending PR with triple superphosphate (TSP) at 75:25 and 50:50 ratios, the biological treatments involved co-application of PR with compost at 50:50 ratio and phospho-compost elaborated from PR (20%), sewage sludge (46%), and wheat residues (34%), while the chemical treatment was obtained by a 30% acidulation of PR by phosphoric acid. Control treatments consisting of zero P application (control), PR alone, and TSP alone were considered to assess the effectiveness of the abovementioned techniques to improve PR agronomic efficiency. A pot experiment was conducted in sandy soil (Jorf Lasfar, central Morocco) for 60 days in a completely randomized design considering eight treatments. All treatments, except the control, were amended with 52 mg kg-1 of P from different PR-based fertilizers before sowing. At the flowering stage (60-day-old plants), results indicated that all PR treatments significantly improved plant growth, root nodulation, and nutrient uptake compared to the control. The relative agronomic efficiency of pretreated PR was significantly higher with phospho-compost treatment (86%) than the partially acidulated PR (78%) or the PR/TSP blend 50:50 (64%). Likewise, P uptake, P use efficiency, number of root nodules, and N uptake all were improved under PR treatments. Our finding revealed that the biological technique based on phospho-compost yielded better compared to chemical and physical treatments.
显示更多 [+] 显示较少 [-]Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France
2008
Banas, Damien | Masson, Gérard | Leglize, L. | Usseglio-Polatera, Philippe | Boyd, C.E. | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL) | Université Paris-Sud - Paris 11 (UP11) | Centre National de la Recherche Scientifique (CNRS) | AgroParisTech | Université Paul Verlaine - Metz (UPVM) | Auburn University (AU)
International audience | Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2–620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L. Effluent phosphorus loads were higher than those reported for more intensive aquaculture ponds, but the pollutant source was catchments rather than feeds and fertilizers.
显示更多 [+] 显示较少 [-]Fate of phosphorus in two constructed wetlands receiving treated wastewater:contributions of free water, soil and plants retention | Le devenir du phosphore dans 2 Zones de Rejet Végétalisées: contributions de l'eau libre, du sol et des plantes
2018
Papias, S. | Masson, M. | Morvannou, A. | Forquet, N. | Boutin, Catherine | Choubert, J.M.
Constructed Wetlands receiving treated wastewater (CWtw) have recently become attractive in France under the perception that they would increase water quality of the WWTP effluent. This study focuses on the fate of phosphorus (P) in 2 pilot-scale CWtw after 2 years of operation considering the 3 components: water, soil and plants. P mass balance was estimated by measures of water balance (inflow outflow and infiltration), flow composite samples, grab samples, water in soil, deposits, soil and plants samples. When considering inlet/outlet an efficiency of 83% and 39 % P removal was observed respectively in M1 and M2. Since the plant uptake was of 15-25 % of total P removal in both systems, the remaining fraction was either retained in the soil or infiltrated. Removal of P by harvesting of aboveground biomass is relevant in that case because of a lightly load system and confirms the need for a harvesting per year to avoid the release of up to 7 kg of P.
显示更多 [+] 显示较少 [-]Phosphorus removal by apatite in horizontal flow constructed wetlands: kinetics and treatment reliability
2008
Harouiya, N. | Molle, Pascal | Prost Boucle, S. | Liénard, A.
Phosphorus removal in constructed wetlands have received particular attention last decades by using specific materials promoting adsorption/precipitation mechanisms. Recent studies have shown interest in using apatite materials to promote P precipitation onto the particle surface. As previous trials were mainly done by lab experiments, this present study aims to evaluate the real potential of apatites to remove P from wastewater in pilots and a full-scale plant. Two different apatites have been studied in 1.5 m² pilots fed with wastewater from the outlet of a trickling filter. They were monitored to follow inlet/oulet flows, hydraulic gradient, meteorological conditions, pH, temperature, and redox potential. Treatment performances were evaluated by regular complete analysis (COD, BOD, SS, nitrogen and phosphorus forms, Ca) as well as PO4-P by a WTW online analyser. At the same time a full-scale experiment study have been done to point out P retention properties in real conditions over a 2 years period. P retention kinetics of two qualities of apatites are presented and discussed according to the temperature dependence. In this work apatite appears to have high retention capacity and is still an interesting way for P removal in constructed wetlands. However, other qualities of apatite must be studied for a better reliability of treatment.
显示更多 [+] 显示较少 [-]Additive effect of calcium depletion and low resource quality on Gammarus fossarum (Crustacea, Amphipoda) life history traits
2018
Rollin, Marc | Coulaud, Romain | Danger, Michael | Sohm, Benedicte | Flayac, Justine | Bec, Alexandre | Chaumot, Arnaud | Geffard, Olivier | Felten, Vincent | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement (INEE) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Stress Environnementaux et BIOsurveillance des milieux aquatiques (SEBIO) ; Institut National de l'Environnement Industriel et des Risques (INERIS)-Université de Reims Champagne-Ardenne (URCA)-Université Le Havre Normandie (ULH) ; Normandie Université (NU)-Normandie Université (NU)-SFR Condorcet ; Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS) | Biocenter, Div. of Developmental Immunology ; Biocenter ; Innsbruck Medical University = Medizinische Universität Innsbruck (IMU)-Innsbruck Medical University = Medizinische Universität Innsbruck (IMU) | Laboratoire Microorganismes : Génome et Environnement (LMGE) ; Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS) | Milieux aquatiques, écologie et pollutions (UR MALY) ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
[Departement_IRSTEA]Eaux [TR1_IRSTEA]BELCA [ADD1_IRSTEA]Systèmes aquatiques soumis à des pressions multiples | International audience | Gammarus fossarum is an often-abundant crustacean detritivore that contributes importantly to leaf litter breakdown in oligotrophic, mainly heterotrophic, headwater streams. This species requires large amounts of Ca to moult, thus allowing growth and reproduction. Because resource quality is tightly coupled to the organism's growth and physiological status, we hypothesised that low Ca concentration [Ca] and low food resource quality (low phosphorus [P] and/ or reduced highly unsaturated fatty acid [HUFA] contents) would interactively impair molecular responses (gene expression) and reproduction of G. fossarum. To investigate the effects of food resources quality, we experimentally manipulated the P content of sycamore leaves and also used diatoms because they contain high amounts of HUFAs. Three resource quality treatments were tested: low quality (LQ, unmanipulated leaves: low P content), high quality 1 (HQ1; P-manipulated leaves: high P content), and high quality 2 (unmanipulated leaves supplemented with a pellet containing diatoms: high P and HUFA content). Naturally, demineralised stream water was supplemented with CaSO4 to obtain three Ca concentrations (2, 3.5, and 10.5 mg Ca L
显示更多 [+] 显示较少 [-]Assessment of currently used organochlorine pesticides in surface water and sediments in Xiangjiang river, a drinking water source in China: Occurrence and distribution characteristics under flood events
2022
Zhang, Shengwei | Zhao, Wenyu | Yang, Chao | Li, Yanxia | Liu, Mengyue | Meng, Xiang−Zhou | Cai, Minghong
Xiangjiang (XJ) is a typical urban inland river that serves as a drinking water source, which may be affected by the currently used organochlorine pesticides (CUOCPs) originating from agricultural activities in the vicinity. On this basis, this study comprehensively explored the occurrence and distribution characteristics of CUOCPs in surface water and sediments under long-term precipitation and subsequent floods. Considering the low concentration of CUOCPs in water, a technique combining high-throughput organic analysis with high-volume solid phase extraction (High-throat/Hi-volume SPE) was introduced for effective analysis of CUCOPs. The results showed that the concentration of CUOCPs in the water and sediments of XJ ranged from 2.33 to 6.40 ng L⁻¹ (average of 3.93 ± 1.15 ng L⁻¹) and from 1.52 to 21.2 ng g⁻¹ (average of 6.60 ± 4.31 ng g⁻¹ dw), respectively. The distribution of CUOCPs in water was consistent throughout XJ, but that in sediments was not uniform, indicating a stronger impact of floods on water than on sediments. Water-sediment partition coefficients were generally >2 L g⁻¹, showing a tendency of CUOCP dominance in sediments. The results of principal component analysis and cluster analysis showed that the occurrence of CUOCPs is significantly affected by exogenous disturbance, which could be flood events; meanwhile, clusters of CUOCPs were found in both water and sediments in the source-limited middle reaches in urban areas. Redundancy analysis (RDA) showed that CUOCP occurrences were not positively correlated with nutrient elements (nitrogen and phosphorus), but related to pH and dissolved oxygen (DO), indicating complex sources.
显示更多 [+] 显示较少 [-]Wood vinegar facilitated growth and Cd/Zn phytoextraction of Sedum alfredii Hance by improving rhizosphere chemical properties and regulating bacterial community
2022
Zhou, Xueqi | Shi, An | Rensing, Christopher | Yang, Jing | Ni, Wuzhong | Xing, Shihe | Yang, Wenhao
Soil Cd and Zn contamination has become a serious environmental problem. This work explored the performance of wood vinegar (WV) in enhancing the phytoextraction of Cd/Zn by hyperaccumulator Sedum alfredii Hance. Rhizosphere chemical properties, enzyme activities and bacterial community were analyzed to determine the mechanisms of metal accumulation in this process. Results demonstrated that, after 120 days growth, different times dilution of WV increased the shoot biomass of S. alfredii by 85.2%–148%. In addition, WV application significantly increased soil available Cd and Zn by lowing soil pH, which facilitated plant uptake. The optimal Cd and Zn phytoextraction occurred from the 100 times diluted WV (D100), which increased the Cd and Zn extraction by 188% and 164%, compared to CK. The 100 and 50 times diluted WV significantly increased soil total and available carbon, nitrogen and phosphorus, and enhancing enzyme activities of urease, acid phosphatase, invertase and protease by 10.1–21.4%, 29.1–42.7%,12.2–38.3% and 26.8–85.7%, respectively, compared to CK. High-throughput sequencing revealed that the D 100 significantly increased the bacterial diversity compared to CK. Soil bacterial compositions at phylum, family and genera level were changed by WV addition. Compared to CK, WV application increased the relative abundances of genus with plant growth promotion and metal mobilization function such as, Bacillus, Gemmatimonas, Streptomyces, Sphingomonas and Polycyclovorans, which was positively correlated to biomass, Cd/Zn concentrations and extractions by S. alfredii. Structural equation modeling analysis showed that, soil chemical properties, enzyme activities and bacterial abundance directly or indirectly contributed to the biomass promotion, Cd, and Zn extraction by S. alfredii. To sum up, WV improved phytoextraction efficiency by enhancing plant growth, Cd and Zn extraction and increasing soil nutrients, enzyme activities, and modifying bacterial community.
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