HighlightsThe proposed article aims to show the interest of the use of sludge in plantation forestry. Secondly, it offers solutions to the problems of storage of sludge at the wastewater treatment.One‐year‐old saplings of Eucalyptus camaldulensis were transplanted into pots with different doses of sludge: 20%, 40% and 60%, mixed with an agricultural soil. Biometric measurements (height, base diameter, diameter at mid‐height and the number of leaves) were performed for six months of planting, showing the positive effect of spreading the sludge on the growth of the plants.A significant difference in height increment and number of leaves was found between the control and sludge‐treated plants. The recorded biometric values were for all the doses, well above those of control plants (100% soil), with high values shown in the mixture of 60% sludge, whereas growth in diameter was not affected by the three treatments.The results obtained were: 493.77 ± 241 mm for height growth and 68.81 ± 6.2 for number of leaves, against: 342.89 ± 128.07 mm for height and 40 ± 3.8 for the number of leaves in control soils.This study also confirms the use of sludge as soil fertilizer in urban areas. The soils of cities are highly heterogeneous and consist of various materials. Thus, the physical properties of these soils are characterized by high compaction, poor ventilation and poor water permeability. It is necessary to provide an amendment of sludge from sewage treatment plants, to create soil suitable for planting trees growing in towns.

This article examines phytoecological aspects of plant groups in the Chebket El Melhassa region (Tiaret-Ouest Algérien) by several types of analysis: biological, biogeographic and statistical. From the plant analysis, a list of 103 taxa distributed in 36 families was compiled, biologically characterized by a dominance of therophytes (45.6%) with species of the Mediterranean biogeographic type 20 species (19.8%) assuming particular importance. The ordination of the plant community was performed in the search for the optimum solution based on correlation with environmental factors, estimated using the phytoindication approach. The results reveal that the plants represented in the community, mostly prefer strongly lit places. Phytoindication shows a warm sub Mediterranean climate. Continentality corresponds to the sub-oceanic climate. The moisture regime ranges from strongly dry to dry soil. The plant community is formed on moderately acid soils. Plants are able to grow on both strongly acidic and neutral soils. The soil is very poor or poor in nitrogen. A four dimension variant of multidimensional scaling procedure was selected as the most appropriate decision. Dimensions selected after nonmetric multidimensional scaling were interpreted by computing weighted average scores of ecological factors for ordination configuration. Four of the plant species clusters were found to be the optimal solution on the basis of the Calinsky-Harabasz criteria. The clusters can be viewed as a functional group. Functional group A is quite diverse and represented by 42 species. This functional group is closest to the community optimum because in all four space dimensions the corresponding cluster is near the origin, which corresponds to the most typical ecological conditions. Species that constitute the group B prefer minimum values of dimension 2. This indicates a preference for illuminated sites with high temperature regime and low soil humidity. This group includes 32 species. A feature of group С is that it is located in the area of maximum values for dimension 2. Thus, this functional group is opposite to functional group B. This indicates a preference of species included in the functional group C for wetter soils. Functional group C comprises 21 species. Functional group D differs considerably from all others in its ecological characteristics. The difference is in the preference for minimum values for measurement 1. This suggests that more acid soils are optimal for a given functional group. Functional group E comprises 8 species.

Sewage sludge is used as a fertilizer in agriculture to rehabilitate deteriorated soils and replace artificial fertilizers. Sludge can be utilized to improve soil characteristics, promote microbial life, and increase plant production where it includes the primary nutrients and organic matter. The current study investigated the impact of the treatment of sewage sludge on the physico-chemical characteristics of the soil, and also on the growth of tomato (Solanum lycopersicum). The experiment consists of using a sludge-soil mixture, with different fractions of sewage sludge: soil control (0% sludge) and 20%, 40%, 60%, 100% of sludge. Biometric measurements (height, stem diameter and number of leaves) were performed on the tomato. The results showed good fertilizing properties of a sludge/soil mixture with the 60% sludge fraction. However, the tomato that grew on the 40% fraction had better growth and high foliage compared to the plants on the other fractions. The spreading of sludge provides a soil amendment and an additional supply of nutrients for tomatoes. The use of 40% fraction of sludge spreading for the cultivation of this plant can maintain better soil fertility while reducing the risk of heavy metal accumulation. Indeed, the 40% fraction of sludge has concentrations which are: 86±0.40 mg/kg for copper, 294 ±0.40 mg/kg for zinc and 50±5.9 mg/kg for lead, lower than the limits recommended by the European directives.

<p>Wastewater treatment always produces a large amount of sludge. The different uses of sludge disposal have negative consequences for the environment. Agricultural use may appear in some situations as an alternative to current solutions, both to optimize the degradation and recycling of organic and mineral elements. During this work, on the one hand, we investigated  the effect of sludge on the growth of turnip (Brassica rapa), a plant that tolerates metallic trace elements, especially lead (Liu et al., 2000) and which is considered a model plant in eco-toxicology (Sun et al., 2010), and on the other hand to determine if it has the potential to be included in phytoremediation systems.</p><p>The seeds were put in different substrates that contained three sludge doses: 20%, 40% and 60%, mixed with agricultural soil  which contained high levels  of metallic trace elements  exceeding the standard eligible concentration  by AFNOR. compared to  the soil, concentrations of potentiall toxic trace elements in sludge were lower than in soil. Morphological measurements were carried out during two months of planting, showing the positive effect of the sludge on the growth of the plant. The recorded biometric values (height, number of leaves, weight, rotation and height of the bulb) for all doses, far exceed those of control plants (100% soil), with high values recorded in the mixture of soil with  60% sludge.</p><p>The concentration of metallic trace elements in the different substrates and also in the leaves and the turnip bulb after two months of planting shows that the plant  accumulates and tolerates hight concentrations of elements  and can therefore be used as a phytoremediator for polluted soils. The highest levels of metal accumulation were observed on the substrate in the  soil mixture  with  60% sludge.</p><p> </p>

The present study aimed at assessing water physicochemical quality of Bougara Dam (Algeria). Water samples were collected in 2019 from different locations within the dam's reservoir for a period of three months (from Mars to May). Several physicochemical parameters (pH, temperature, electrical conductivity (EC), dissolved oxygen (DO), dry residuals, oxidizable matter (OM), nitrate (NO3 -), ammoniacal nitrogen (NH4 + ), chloride (Cl -), phosphates (PO₄³⁻), biological oxygen demand (BOD5) and chemical oxygen demand (COD)) were measured. The result of this research showed that mean values of studied parameters, except phosphates and ammoniacal nitrogen concentrations were within the permissible limit of standards established by the National Agency for Hydraulic Resources (ANRH) and Algerian standards for surface water. These findings constitute a basis for monitoring the physicochemical quality of water in the study area.