Environmental and landscape rehabilitation: case study for fresh stone treatment on big dams

The construction of big dams usually cause a severe environmental change at a local level, producing a considerable visual impact that must be remedied and the disturbed area must be rehabilitated and recovered, approaching the landscape prior to the dam construction. In this work, several assays were tested, with the purpose of finding a treatment for fresh cut granite that could be used as a general rock treatment for visual impact of fresh excavated rocks. Some organic mixtures were tried, using autochthonous lichens and moss, as well as chemical treatments, like acid or paint. Granite blocks were selected and five different treatments were applied to cover the fresh granitic blocks and trigger their colonization and aging. The experiment has been established on two groups of blocks, one submitted to irrigation three times a week and the other without irrigation. Each treatment had two repetitions per group. Two blocks for control were also established in each group to interpret the gaps of variation in comparison to the treated blocks. All the stone blocks were maintained in a greenhouse, with controlled temperature and humidity. The monitoring of the treatment was done by taking pictures every 20 days, that were analyzed using RGB color characteristics and parameters that shows the evolution of pigmentation of the blocks. The results of this study show that three or at least two out of the five tested treatments are recommended to use in the disturbed areas. Irrigation can be more useful for the first two to three weeks after treatmentsinfo:eu-repo/semantics/submittedVersio

Dynamic composting optimization through C/N ratio variation as a startup parameter

Different organic wastes (waste of tomato leaves and stems, sheep manure, olive mill waste and melon waste) were mixed with different proportions for different C/N ratio to make better use of tomato waste as it constitutes the majority of horticultural waste in the Souss-Massa region (south-western of Morocco). The objective of this study was to evaluate the effect of C/N ratio on the physicochemical parameters during aerobic composting process (temperature, relative humidity, pH, EC...), and the quality of the compost. The effect of each produced compost was also tested by its incorporation at different rates into sandy soil. The four studied C/N ratios (treatments) were: C/N=25; C/N=30; C/N=35 and C/N=40. Results revealed that the treatment C/N=35 has resulted in the highest oxygen consumption and also, the longest thermophilic phase. Treatments C/N=25 and C/N=35 have reached optimal C/N ratios at the end of the process (respectively 11.88 and 14.71), while treatments C/N=30 and C/N=40 stood higher than 15 (respectively 17.93 and 18.84). Fulvic acid evolution remained constant for all treatments, whereas humic acid content has reached highest levels with C/N=25 and C/N=35 treatments. The effect of compost on seed germination test and phytotoxicity test showed that treatment C/N=35 has produced the most mature compost with the lowest phytotoxicity effect. The amendment of compost has reduced the pH, increased the EC, and enriched soil with organic matter as far as the rate of the amendment is increasing (10; 20 and 30Tonnes.ha-1). Compost of treatment C/N=40 has recorded the highest soil total organic matter content poorly decomposed during composting. However compost of treatment C/N=35 has resulted in the lowest soil total organic matter content, this is mainly due to the intense degradation of the compost during the composting process. The quality of the produced compost depends largely on the level of C/N startup ratio and also the quality of its constituents within the mixture

The 4p1000 initiative : opportunities, limitations and challenges for implementing soil organic carbon sequestration as a sustainable development strategy

Authors would like to acknowledge the executive secretariat of the 4p1000 initiative, Charlotte Verger and Claire Weill for their valuable contributions during the preparation of this manuscript. The input of PS contributes to the UK NERC-funded Soils-R-GGREAT project (NE/P019455/1).Peer reviewedPostprin

Contribution à l'étude du pouvoir minéralisateur des sols en régions semi-arides: cas du Maroc

dissertn: Diss. Doct

Les évaluations environnementales: Etude d'impact sur l'Environnement (EIE) et Evaluations Environnementales Stratégiques (EES)

Actes du Séminaire international tenu les 21 et 22 novembre 2013, à Rabat, Maro

Evaluation of nitrogen fertilizing value of composted household solid waste under greenhouse conditions

Accumulation of municipal solid wastes, such as household solid waste, can be rated as a harmful, if not critical, pollution problem. However, if these wastes can be composted and the end product used as soil organic amendment or fertilizer, this may represent one of the alternatives for achieving the goal of ensuring integrated and sustainable waste management. The objective of the present work is to evaluate the nitrogen fertilizing value of household solid waste compost in two soils of Morocco with contrasting properties: a sandy soil and a loamy-clay soil. The compost used in this study was prepared by aerobic biodegradation using the organic fraction after its separation from the non-compostable materials. A study of nitrogen availability of the compost was carried out in a Soil – Compost – Crop system under greenhouse conditions using lettuce as a test crop. Four increasing compost rates of 0, 10, 20 and 30 tons/ha were applied to the soils. The recommended mineral fertilizer rate by the Agricultural Extension Service for lettuce and its half values constituted additional treatments. The results show a high stock of mineral nitrogen in the loamy-clay soil before crop installation. Unlike the loamy-clay soil, the sandy soil generated a better yield increase and a better response to mineral fertilizers. The effect of compost rate on nitrogen mineralization was significant in the two studied soils. The quantities of mineralized nitrogen of the compost varied between 15 and 24% of the compost total nitrogen applied to the sandy and the loamy-clay soils during the lettuce growing season. Therefore the use of household solid waste compost as soil amendment constitutes a beneficial alternative in Mediterranean soils because it permits the generation of a high nitrogen fertilizing value

Developping an optimal soil and water quality monitoring network for the Triffa irrigated perimeter (Eastern of Morocco)

In Morocco, the irrigated areas play a key role as real centers for agricultural and rural development, both at local and regional level. Thus, the irrigated agriculture contributes to about 45% on average of the agricultural value added. However, it is noted that the water and soil of different irrigated areas are excessively exploited and threatened by different degradation problems. In this study, we aim to design an advanced methodology allowing to monitor soil and water quality in the irrigated perimeter of Triffa. The study area is the most fertile and productive agricultural region of north-east Morocco.The surface area of the plain rises to 61 000 ha of which 36 060 ha are irrigated. The climate is warm semi-arid. The mean annual rainfall in 28 years is 331 mm. The mean annual temperature is 17.2 ◦C. Recognized by the quality of its clementine, the Triffa plain experienced during the last decade a large and rapid expansion of irrigated areas mainly citrus through improved irrigation. Recent studies have shown that in this region, soil and water resources are under pressure due to salinization and groundwater nitrate pollution. The degradation of soil and water resources is largely caused by the increased use of agrochemicals, such as nitrogen fertilizers and pesticides, and the lack of control of irrigation and drainage of the plots. The protection and the preservation of these resources are top priority necessities, particularly in arid zones. We first aim to identify robust indicators of soil and groundwater degradation. These indicators should be able to measure the different functions and services provided by the soil and water system. Subsequently, we will design a spatial network allowing to evaluate the state of the soil and water resource. We will use geostatistical and GIS tools to optimize the monitoring network. This study is undertaken within the framework of a CUD-PIC project, aiming to develop tools for the management of water and soils resources in the irrigated perimeter of Morocco

Elucidation of functional chemical groups responsible of compost phytotoxicity using solid-state 13C NMR spectroscopy under different initial C/N ratios

International audienc