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In recent years, increasing efforts have focused on production of organic-inorganic compound fertilizers using ammonium sulfite pulping waste liquor. However, their ecological effects on soil have not been studied. In this study, earthworm Eisenia fetida was exposed to various doses (0, 0.13, 0.26 and 0.52 kg/m2) for different time (7, 14, 21, and 28 d) to evaluate the effects of fertilizers made from pulping waste liquor, including reactive oxygen species (ROS) generation, antioxidant enzymes activities, glutathione S-transferase enzyme (GST) activity, malondialdehyde (MDA) content and DNA damage. Results showed that there were significant increase of ROS and MDA levels after 14 d, inducing production of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)) as well as GST. Before 14 d, excess ROS and MDA caused damage to the DNA of earthworms, leading to gradual increase of Olive tail moment (OTM) in the comet assay. With the exposure time extended to 28 d, owing to the combined effects of elimination of free radicals by antioxidant enzymes and detoxification enzymes as well as self-repairing function of cells, ROS and MDA levels declined slightly and OTM gradually decreased. In summary, this study indicated that there was a toxicological effect on earthworms when fertilizers made from pulping waste liquor were applied to soil, which needs more attention.

Alkaline residuals, such as wood ash and lime mud generated from pulp and paper mills, could be recycled as liming agents in sugar maple (Acer saccharum Marsh.) forests affected by soil acidification. The objectives of this study were (1) to evaluate soil chemistry, in particular soil acidity, after the application of three alkaline residuals from the pulp and paper industry, and (2) to determine if these alkaline residuals altered soil greenhouse gas (GHG) emissions as a result of the change in soil pH or due to their chemical composition. Soil properties and GHG fluxes were monitored for two years after alkaline residuals were applied to six forest sites dominated by sugar maple in southeastern Quebec, Canada. Each site received six treatments: wood ash applied at 5, 10 and 20 t ha−1, lime mud (7.5 t ha−1), a mixture of slaker grits and green liquor sludge (7 t ha−1) and an unamended control. These treatments had acid-neutralizing power from 0 to 9 t ha−1. All alkaline residuals buffered soil acidity as a function of their neutralizing power, and more neutralization occurred in the forest floor layer than in the underlying mineral soil. In the forest floor, the alkaline residual treatments significantly increased pH by more than one unit, nearly doubled the base saturation, and reduced exchangeable acidity, Al and Fe concentrations compared to control plots. The CO2 and N2O fluxes were lower after application of alkaline residuals, and this was related to the soil pH increase and the type of alkaline residual applied. Lime mud was more effective at reducing GHG fluxes than other alkaline residuals. We conclude that these alkaline residuals can effectively counteract soil acidity in sugar maple forests without increasing soil GHG emissions, at least in the short term.

The disposal of industrial paper mill sludge waste is a big issue and has a great importance all over the world. A study was conducted to determine the chemical properties of recycled paper mill sludge (RPMS) and assess its possibilities for land application. RPMS samples were collected from six different paper mills in Malaysia and analyzed for physical and chemical properties, heavy metals, polycyclic aromatic hydrocarbons, (13)C-NMR spectra and for the presence of dioxins/furans. The RPMS was dewatered, sticky with a strong odour, an average moisture of 65.08%, pH 7.09, cation exchange capacity (CEC) 14.43 cmol (+) kg(-1), N 1.45, P 0.18, K 0.12, Ca 0.82, Mg 0.73, Na 0.76 and Al, 1.38%. The polycyclic aromatic hydrocarbons (PAHs) and heavy metals levels were below the standard Class 2 limits. The dioxin and furan were in below the standard concentration of Class 1. The most prominent peak in the (13)C-NMR spectra of RPMS was centered at 31 ppm, proving the presence of methylene (-CH2) groups in long aliphatic chains, with lipids and proteins. The signal at 89 ppm and highly shielded shoulder at 83 ppm were due to presence of cellulose carbon C-4, and the peak at 63 and 65 ppm was due to the cellulose carbon spectrum. The RPMS therefore contains significant amount of nutrients with safe levels of heavy metals and PAHs for environment and can be used as a fertilizer and soil amendment for land application.

This synthesis report details the process, outputs and intermediate outcomes of the World Bank’s Water and Sanitation Program (WSP) Technical Assistance (TA) to Support Government of India for implementation of the National Urban Sanitation Policy (P131963). The objective of this TA was to (i) strengthen urban sanitation services and target the urban poor by development of strategies for regulation, funds allocation, improved accountability mechanisms and implementation of inclusive sanitation policies at national level and in at least five states, with two of these low-income states (LIS). This was to be supplemented with (ii) enabling design and use of improved performance monitoring systems by Government of India, 3 states and 300 urban local bodies by 2015, and (iii) strengthen capacity of local urban government institutions to provide improved – inclusive and sustainable – sanitation services for all. This TA provides the building blocks for sustainable sanitation improvements which are being adopted and implemented as part of another TA (P131967) in Madhya Pradesh and Tripura to pilot and operationalize City Sanitation Plans (CSPs) towards outcome oriented sector improvements. The areas addressed in this TA include the following specific goals of the NUSP: open defecation free cities, and integrated city-wide sanitation. The TA provided assistance to central government and the states in putting in place various elements identified as necessary for sector improvement, including planning, provisioning and monitoring processes. The TA also identified the need for the cities to see opportunities for financial recovery of investments through reuse and recycle strategies, to strengthen the incentive for investment in sanitation improvements.

Environmental problems associated with sewage sludge disposal have prompted strict legislative actions over the past few years. At the same time, the upgrading and expansion of wastewater treatment plants have greatly increased the volume of sludge generated. The major limitation of land application of sewage sludge compost is the potential for high heavy metal content in relation to the metal content of the original sludge. Composting of sewage sludge with natural zeolite (clinoptilolite) can enhance its quality and suitability for agricultural use. However, the dewatered anaerobically stabilized primary sewage sludge (DASPSS) contained a low concentration of humic substances (almost 2%), and the addition of the waste paper was necessary in order to produce a good soil conditioner with high concentrations of humics. The final results showed that the compost produced from DASPSS and 40-50% w/w of waste paper was a good soil fertilizer. Finally, in order to estimate the metal leachability of the final compost product, the generalized acid neutralization Capacity (GANC) procedure was used, and it was found that by increasing the leachate pH, the heavy metal concentration decreased. The application of the sequential chemical extraction indicated that metals were bound to the residual fraction characterized as a stabilize fractions.

Use of organic by-products as soil amendments in agricultural production exemplifies a strategy for converting wastes to resources. The overall objective of this research was to evaluate the short- and intermediate-term effects of repeatedly amending sandy soil with paper mill residuals (PMR) and composted PMR in a vegetable rotation in Wisconsin's Central Sands. Specifically, we investigated the effects of PMR and composted PMR on total soil C and related these to changes in water-holding capacity and plant-available water (PAW). Amendment effects on irrigation requirements were estimated with a simple soil water balance model. The experimental design was replicated five times as a randomized complete block with four organic amendments: raw PMR, PMR composted alone (PMRC), PMR composted with bark (PMRB), and peat applied at two rates and a non-amended control. All amended treatments significantly increased total soil C relative to the nonamended control following applications in 1998 and 1999. One year following the second serial amendment, all PMR treatments increased PAW by 5 to 45% relative to the control. There was a significant positive linear relationship between total soil C and PAW. All amended treatments reduced the average amount of irrigation water required for potato production by 4 to 30% and the number of irrigation events by 10 to 90%. There was a clear trend of greater reduction in irrigation requirements with more carbon added. The cumulative effects of repeated additions of PMRB suggest that certain composts might sustain elevated PAW and reduce irrigation requirements beyond one year.

The ferti-irrigational effect of an agro-based paper mill effluent on Abelmoschus esculentus (var. IHR-31) was investigated. Different doses of paper mill effluent viz. 5, 10, 25, 50, 75 and 100% were used for fertigation ofA. esculentus along with bore well water (control). The study revealed that paper mill effluent had significant (p0.05) effect on EC, pH, OC, Na+, K+, Ca2+, Mg2+, Fe2+, TKN, PO4(3-), SO4(2-), Cd, Cr, Cu, Mn and Zn of the soil in both seasons. Insignificant (p0.05) changes in WHC and bulk density of the soil were observed after irrigation with paper mill effluent. The agronomical performance of A. esculentus was increased from 5 to 25% and decreased from 50 to 100% concentration of paper mill effluent as compared to control in both seasons. The heavy metals concentration was increased in A. esculentus from 5 to 100% concentrations of paper mill effluent in both seasons. Biochemical components like crude proteins, crude fiber and crude carbohydrates were found maximum with 25% paper mill effluent in both seasons. The order of Contamination Factor (Cf) of various heavy metals was CrCdMnZnCu for soil and ZnMnCuCrCd for A. esculentus plants after fertigation with paper mill effluent. Therefore, paper mill effluent can be used as a biofertigant after appropriate dilution to improve yield of A. esculentus.

In the present study the change in metal content on vermicomposting of paper mill solid waste was studied. On vermicomposting, quantity of iron, zinc and chromium found to be increased whereas quantity of aluminium, copper, manganese, nickel and lead found comparatively low. The bioaccumulation of any metal was not observed in the body of the earthworm, hence after vermicomposting, there is no harm to fishes to utilize earthworm biomass as their food. The metal content in the vermicompost prepared from the paper mill solid waste was well within the permissive limits and can therefore be safely applied in an aquaculture, agriculture and other food production systems.