Recycling mineral nutrients to farmland via compost application

2006 ◽  
Vol 53 (2) ◽  
pp. 111-118 ◽  
Author(s):  
Y.Y. Liu ◽  
M. Ukita ◽  
T. Imai ◽  
T. Higuchi

Increased cultivation of farmland has resulted in nutrient deficiency and consequently fertility degradation of soils. This research examined the application of composted wastes in terms of the feasibility and effectiveness of recycling plant essential minerals. Minerals in composts (derived from sewage sludge, livestock excrement, and municipal solid wastes, respectively) and in amended soils were observed. Ca/Mg ratios in amended soils and the effect of compost applications (mineral nutrients and heavy metals) on plant uptake were also studied. Results showed that composts, especially those made from sewage sludge and livestock excrement, were richer in mineral nutrients but also contained more heavy metals than untreated soil. The increase in some elements and plant-growth-essential Ca/Mg ratios were found in amended farmlands, implying that compost applications have made up for the nutrient deficiency and have adjusted chemical conditions of the soil. The soil contamination from heavy metals was noticeable. However, some results showed that the large existence of mineral nutrients and heavy metals in soils has caused no significant increase in the plant uptake of elements. The controlled composting process and farmland uses are believed necessary for reducing the heavy metal accumulation in agricultural plants.

2004 ◽  
Author(s):  
Edmundo Robledo S. ◽  
Joel Pineda P. ◽  
Ranferi Maldonado T. ◽  
Esteban Martínez V. ◽  
Edna Álvarez S. ◽  
...  

Geoderma ◽  
2007 ◽  
Vol 142 (3-4) ◽  
pp. 262-273 ◽  
Author(s):  
M.J. Sánchez-Martín ◽  
M. García-Delgado ◽  
L.F. Lorenzo ◽  
M.S. Rodríguez-Cruz ◽  
M. Arienzo

Water SA ◽  
2018 ◽  
Vol 44 (4 October) ◽  
Author(s):  
Awonke Mbangi ◽  
Pardon Muchaonyerwa ◽  
Rebecca Zengeni

Long-term application of sewage leads to heavy metal accumulation in soils, causing serious risks to plants, humans, animals and the environment, and phytoremediation could be essential. A study was conducted to determine the concentration of heavy metals in self-seeding vegetables, amaranthus (Amaranthus dubius), tomato (Solanum lycopersicum), black nightshade (Solanum nigrum), Rumex pulcher and turf grass, grown on land treated with sewage sludge for over 50 years. A pot experiment was conducted to determine phytoremediation potential of Indian mustard (Brassica juncea), lucern (Medicago sativa), vetch (Vicia sativa), rape (Brassica napus) and ryegrass (Lolium perenne), using the same soil. Another pot experiment was conducted to determine effects on tissue metal composition of Indian mustard of adding increasing concentrations of EDTA. All the self-seeding vegetables had tissue Zn, Cu, Cr, Ni, Cd and Pb concentrations higher than toxicity thresholds. Turf grass tissue had higher concentrations of all the metals than all the self-seeding vegetables growing on the soil. Indian mustard and rape had the highest biomass and tissue concentration of most of the metals studied. Addition of EDTA to the soil drastically increased uptake of Zn, Cu, Cd and Pb but not Cr and Ni. The findings of this study imply that self-seeding vegetables and turf grass growing on the polluted soils pose serious health risks and that Indian mustard, and to some extent rape, have potential for phytoremediation, especially if grown on the soil treated with EDTA.


Soil Research ◽  
2006 ◽  
Vol 44 (6) ◽  
pp. 619 ◽  
Author(s):  
Mónica Antilén ◽  
Nadia Araya ◽  
Margarita Briceno ◽  
Mauricio Escudey

Forest fires are frequent in central-southern Chile; high temperatures may affect chemical fractions of heavy metals (Cu, Zn, Ni, Pb, Cd, Mo, Cr, and Mn) naturally present in soils and those coming from sewage sludge amendment. Changes in exchangeable, sorbed, organic, carbonate, and residual heavy metals fractions, evaluated by sequential extraction, were observed after heating at 400°C in 2 amended volcanic soils. Most significant heavy metals in these samples were Cu, Zn, Pb, and Ni. A significant increment in the total content of organic matter and metal ions, such as Zn and Cu, was observed in amended soils with respect to controls. In all samples, sorbed and exchangeable forms represent <10% of the total amount, while organic and carbonate fractions represent 24 and 48%, respectively. The thermal treatment of amended soil samples results in a redistribution of the organic fraction, mainly into more insoluble carbonate and residual fractions such as oxides. Finally, the thermal impact is much more important on sewage sludge amended soils if a heavy metal remediation process is considered, reducing the mobility and solubility of heavy metals supported by sewage sludge, minimising leaching and promoting accumulations in surface horizons.


2007 ◽  
pp. 227-237
Author(s):  
Nataliia Suchkova ◽  
Yuri Vergeles

The contamination of the sewage sludge fields of municipal wastewater treatment plants (WWTPs) by heavy metals, hydrocarbons or other pollutants is a major environmental problem. Sludge can retain up to 96% of all the metals entering the WWTPs in sewage, therefore, when it is disposed to land, heavy metals will be accumulated in the soil. Effects of heavy metal accumulation are long lasting and even permanent. Phytotoxicity is the main problem, although metals can be transferred directly to man via vegetables and other crops or indirectly via animals, primarily cattle, eating herbage (zootoxic). The common metals in sludge are Zn, Cu, Ni, Pb, Cr, and Cd which are generally the most toxic metal found in high concentration.Conventional treatment techniques of contaminated territory suffer from serious shortcomings which limit their applicability and efficiency. These include high cost and maintenance requirements, the need to transfer the contamination from one medium to another, and the extended duration of the operation. Alternatives to these treatments lie in in­situ phytoremediation. Plants are among the most tolerant organisms to pollution, which emphasizes their utility for the detoxification or degradation of pollutants. The concept of phytoremediation was inspired by the discovery of hyper-accumulators, most of which belong to the botanical families Brassicaceae, Poaceae, Papilionaceae, Caryophyllaceae, and Asteraceae, which provide most of the candidates for heavy metal phytoremediation. Two other families are important - the Salicaceae with the genera Salix and Populus, which are effective against a range of pollutants; and the Betaceae which contribute species effective against salt ions and small (few rings) polycyclic aromatic hydrocarbons (PAHs). Some Asteraceae species have been shown to be good phytoremediants of radionuclide pollution [ I ].This paper summarizes the results obtained from laboratory, as well as from in-situ experiments (sludge fields at Kharkiv's WWTP, total area is approx. 126 ha) which focused on phytoremediation methodologies for the removal of heavy metals from sewage sludge.


2019 ◽  
Vol 37 (3) ◽  
pp. 243
Author(s):  
Martha Alicia Velázquez Machuca ◽  
Juan Rosario Equihua Soriano ◽  
José Venegas González ◽  
José Luis Montañez Soto ◽  
José Luis Pimentel Equihua ◽  
...  

Pyrolysis treatment of sewage sludge to generate biochar is one of the current alternatives for environmental management of this waste. The treatment transforms sewage sludge into biochar, conserves some of the characteristics that give it an important agronomic value and reduces its pathogen content. The objective of this study was to analyze the potential use of the sewage sludge biochar obtained from the wastewater treatment plant (WWTP) of Morelia, Michoacán, México, as an agricultural soil improver considering the physical-chemical properties of the material and its content of nutrients and heavy metals as indicators. The sewage sludge was subjected to pyrolysis (SSB) in an experimental scale reactor that uses solar energy, with six residence times and temperature of 280 to 355 oC. The parameters analyzed were: pH EC, OM, Cu, Mn, Zn, Fe available (DTPA and EDTA), elemental composition (C, N, O, Ca, Mg, Na, K, P, S, Cl, Si, Al, Fe, Mn, Cu, Zn, Ti, Ni, Cr, Cd and Pb). The EC of the SSB obtained was from 592 to 5240 μS cm‑1, pH = 6.33 to 7.02, OM = 3.8 to 5.6%, high contents of C, N, P (31 to 38%, 6.5 to 7.7% and 37.7 to 48.8 g kg‑1, respectively), low Na/Ca ratio and a low content of total and available heavy metals. The properties of the SSB obtained indicate that it can be used as an agricultural soil improver since it is a material with high nutrient content and low environmental risk in terms of its low heavy metal content. These results should be complemented with studies on the response of plants to BLR, monitoring of physical-chemical conditions and analysis of organic contaminants in soil and water where this material is applied.


Sign in / Sign up

Export Citation Format

Share Document