scholarly journals The Terraces of the Anti-Atlas: From Abandonment to the Risk of Degradation of a Landscape Heritage

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 510
Author(s):  
Mohamed Sabir

The Anti-Atlas is subject to an intense rural exodus. The agricultural terraces built for several centuries have been abandoned. They are gradually deteriorating. The risks of runoff and erosion are becoming significant. The objective was to study the effect of the abandonment of terraces on the risks of runoff and erosion in the territory of two villages, Tizerkine and Timzemzit. After the characterization of the soil surface conditions, the extent of erosion and the risk of runoff were qualified according to the age of abandonment. Erosion was assessed by estimating the “soil surface factor” (PAP/CAR method) and infiltration by the double ring method. The abandonment of the terraces has led to a reduction in the plant cover of the soil surface and its opening and to enhancing its compaction. The risk of runoff is high. A year of abandonment reduced the infiltration from 301.8 mm/h (SD: 105.8 mm/h) to 129.6 mm/h (SD: 28.9 mm/h). Furthermore, 5 years of abandonment reduced it to 62.9 mm/h (SD: 14.9 mm/h). The walls of the terraces are gradually being destroyed with an increasing age of abandonment. More than half (57%) of the terraced slope surface has suffered moderate to high water erosion. More than 11% of the surfaces are severely degraded after 20 years of abandonment. The heritage made up of these managed slopes is being lost. Particular attention must be paid to these landscapes in order to better rehabilitate and develop them.

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 295
Author(s):  
Marina Moura Morales ◽  
Nicholas Brian Comerford ◽  
Maurel Behling ◽  
Daniel Carneiro de Abreu ◽  
Iraê Amaral Guerrini

The phosphorus (P) chemistry of biochar (BC)-amended soils is poorly understood. This statement is based on the lack of published research attempting a comprehensive characterization of biochar’s influence on P sorption. Therefore, this study addressed the kinetic limitations of these processes. This was accomplished using a fast pyrolysis biochar made from a mix of waste materials applied to a highly weathered Latossolo Vermelho distrofico (Oxisol) from São Paulo, Brazil. Standard method (batch method) was used. The sorption kinetic studies indicated that P sorption in both cases, soil (S) and soil-biochar (SBC), had a relatively fast initial reaction between 0 to 5 min. This may have happened because adding biochar to the soil decreased P sorption capacity compared to the mineral soil alone. Presumably, this is a result of: (i) Inorganic phosphorus desorbed from biochar was resorbed onto the mineral soil; (ii) charcoal particles physically covered P sorption locations on soil; or (iii) the pH increased when BC was added SBC and the soil surface became more negatively charged, thus increasing anion repulsion and decreasing P sorption.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rekha A. ◽  
Vidhya A.

Recent research suggests that biochar is a promising approach to minimize soil contamination caused by heavy metals and organic pollutants. It is also involved in the amendment of soil by altering the nutrients, pH and other factors. Through intensive literature review, this paper was aimed to better understand the selection of feedstock processes, preparation, and characterization of biochar. Wide variety of feedstock used for the biochar production based on the cost effectiveness, ease availability and they are ecofriendly to the environment. Among the thermochemical processes, pyrolysis is the promising techniques followed for the production of BC. The stabilization efficacy was mainly determined by cation exchange capacity, pH, and ash content of the biochar. The physicochemical characteristic of the biochar is analyzed using various methods such as SEM, FTIR, TGA and BET analysis. The surface area plays a major role in the metal sorption. The quality characteristics of biochar as a soil amendment varied greatly with the feedstock materials and the pyrolysis conditions. Biochar plays a great role in increasing the pH which helps the acidic soil region and its high-water retention capacity enhance the moisture level in the soil which enhances the microbial communities and its activity. Biochar becomes stabilized in the soil by interacting with soil particles. The inherent characteristics of the biochar as dictated by feedstock and pyrolysis conditions, interact with climatic conditions such as precipitation and temperature to influence how long biochar carbon remains stored in the soil. Due to its carbon sequestration in the soil, it helps in increasing the fertility of the soil and also enhances the crop yield.


2018 ◽  
Author(s):  
Bruno J. Cardoso ◽  
Adélio Rodrigues Gaspar ◽  
José Carlos Góis ◽  
Eugénio Rodrigues

Indoor swimming pools have high water and energy (electricity and natural gas) consumption levels due to the need to provide suitable thermal comfort conditions (temperature and relative humidity) to its occupants and to counterbalance losses (evaporation, ventilation, etc.). In Portugal, most of the swimming pool facilities belong to the municipalities and their operation represent a considerable financial burden. This work intent to characterize and benchmark the energy (electrical and thermal) and water consumption of five sport complexes with indoor swimming pools, located in two cities of the Centre of Portugal. The four most commonly performance indicators used in the literature were calculated and analyzed according to the operating time and services. Some measures are suggested to enhance the energy efficiency as well as to reduce the consumptions.


Botany ◽  
2018 ◽  
Vol 96 (11) ◽  
pp. 779-791 ◽  
Author(s):  
Félix Gagnon ◽  
Line Rochefort ◽  
Claude Lavoie

There are very few studies on the spontaneous revegetation of cutover fens or bogs from which peat has been extracted to the minerotrophic layers. Most peatlands with fen-type residual peat have problems regenerating a plant cover satisfactorily from a restoration point of view. We nevertheless found a site (Moss Spur, Manitoba, Canada) presenting a substantial and diversified spontaneous plant cover. We estimated that the site would provide insights about natural revegetation processes operating in peatlands. Vegetation assemblages and environmental conditions were surveyed 19 years after extraction activities ceased. Moss Spur has densely revegetated (163 plant species, vegetation cover of 94%) with minimal human assistance. However, the composition of plant assemblages varies considerably across the site, depending on certain abiotic variables, particularly water pH, water table level, and the thickness of the residual peat layer. Moss Spur was remarkably wet considering the past peat extraction activities and the absence of active rewetting procedures. The high water table level may in part explain the successful revegetation. However, plant assemblages were not of equal quality from a restoration perspective. Some assemblages were highly diversified, and especially those dominated by Scirpus cyperinus, a species that should be further considered in peatland restoration projects to direct the recovery of the peatland towards a natural fen species composition.


2005 ◽  
Vol 96 (1) ◽  
pp. 78-86 ◽  
Author(s):  
N. Holah ◽  
N. Baghdadi ◽  
M. Zribi ◽  
A. Bruand ◽  
C. King

Author(s):  
Fernando Gomes de Souza ◽  
Valdinar Ferreira Melo ◽  
Wellington Farias Araújo ◽  
Thiago Henrique de Castro Araújo

Currently in Brazil, the main form of erosion is caused by the impact of raindrops on the soil surface, triggering the process of water erosion and causing serious damage to agricultural areas. This study evaluated losses of soil, water, organic carbon and nutrients in different cultures, bare soil and savanna under natural rain. The experimental design was completely randomized with five treatments (bare soil - BS, cowpea bean - CB, Brachiaria brizantha - BB, corn - CO and natural savanna – SN) with three replications; The treatment of bare soil (BS), followed by the treatment cultivated with cowpea bean  (CB) showed higher losses of soil, water, organic carbon and nutrients; The highest losses of soil, water, organic carbon and nutrients in the treatment of bare soil (BS) occurred during the period of greatest erosivity; but for treatments CB, BB and CO, the highest losses occurred during the establishment of the crop, in view of the lower soil cover. Soils cultivated with Brachiaria brizantha - BB, corn - CO and in the Natural Savana - SN area were more efficient in reducing soil and water losses during all months evaluated. Plant cover produced by the (SN) treatment and by the (BB) and (CO) treatments acted to reduce the harmful effects of erosion, minimizing losses of nutrients and organic carbon. The soil should be well protected during periods when rainfall presents the highest values of erosivity index.


2018 ◽  
Vol 18 (6) ◽  
pp. 1946-1955 ◽  
Author(s):  
Miguel Ángel López Zavala ◽  
Mónica José Cruz Prieto ◽  
Cristina Alejandra Rojas Rojas

Abstract In this study, the reliability of using rainwater harvesting to cover the water demand of a transportation logistics company located in Mexico City was assessed. Water consumption in facilities and buildings of the company was determined. Rainwater potentially harvestable from the roofs and maneuvering yard of the company was estimated based on a statistical analysis of the rainfall. Based on these data, potential water saving was determined. Characterization of rainwater was carried out to determine the treatment necessities for each water source. Additionally, the capacity of water storage tanks was estimated. For the selected treatment systems, an economic assessment was conducted to determine the viability of the alternative proposed. Results showed that current water demand of the company can be totally covered by using rainwater. The scenario where roof and maneuvering yard rainwater was collected and treated together resulted in being more economic than the scenarios where roof and maneuvering yard rainwater was collected and treated separately. Implementation of the rainwater harvesting system will generate important economic benefits for the company. The investment will be amortized in only 5 years and the NPV will be on the order of US$ 5,048.3, the IRR of 5.7%, and the B/I of 1.9.


2020 ◽  
Vol 981 ◽  
pp. 132-137
Author(s):  
Suharno Rusdi ◽  
Ridwan A. Destian ◽  
Fitratur Rahman ◽  
Achmad Chafidz

Everyday human life cannot be separated from plastic. Almost all objects that are around us are made of plastic. In general, plastics are non-biodegradable, causing environmental problems caused by the increased volume of plastic waste. One way to overcome this is by recycling existing plastic waste. But the use of recycled plastics is very limited and considered inefficient because the process is more difficult and processing is more expensive than buying new plastic raw materials. Another alternative is to use bioplastics or biodegradable plastic. This plastic is more environmentally friendly because it is biodegradable or easily decomposed by microorganisms. Basically, bioplastics can be made from vegetable starches. In this study we will use starch extracted from banana peel waste as a base material for making bioplastics. In this research, glycerin which is used as a bioplastic adhesive or plasticizer will be used. Whether or not bioplastics depend on the resistance to water, the attractiveness of the bioplastics, the ability of the plastic to be decomposed by microorganisms. From this research, it is expected to produce bioplastics with high water resistance and high tensile strength and easy to decompose microorganisms.


Sensors ◽  
2020 ◽  
Vol 20 (13) ◽  
pp. 3756
Author(s):  
Marta Cavagnaro ◽  
Giuseppe Ruvio

Dielectric characterization of biological tissues has become a fundamental aspect of the design of medical treatments based on electromagnetic energy delivery and their pre-treatment planning. Among several measuring techniques proposed in the literature, broadband and minimally-invasive open-ended probe measurements are best-suited for biological tissues. However, several challenges related to measurement accuracy arise when dealing with biological tissues in both ex vivo and in vivo scenarios such as very constrained set-ups in terms of limited sample size and probe positioning. By means of the Finite Integration Technique in the CST Studio Suite® software, the numerical accuracy of the reconstruction of the complex permittivity of a high water-content tissue such as liver and a low water-content tissue such as fat is evaluated for different sample dimensions, different location of the probe, and considering the influence of the background environment. It is found that for high water-content tissues, the insertion depth of the probe into the sample is the most critical parameter on the accuracy of the reconstruction. Whereas when low water-content tissues are measured, the probe could be simply placed in contact with the surface of the sample but a deeper and wider sample is required to mitigate biasing effects from the background environment. The numerical analysis proves to be a valid tool to assess the suitability of a measurement set-up for a target accuracy threshold.


1991 ◽  
Vol 260 (3) ◽  
pp. F311-F316 ◽  
Author(s):  
K. Yoshitomi ◽  
M. Imai

The upper portion of the descending limb of long-looped nephron (LDLu) of the hamster is characterized by high water and ion permeabilities. Although the paracellular route is considered to be the major pathway representing cation permselectivity of this segment, ion transport mechanisms through the transcellular pathway are unknown. To study this issue; we applied cable analysis and conventional microelectrode technique to the hamster LDLu perfused in vitro. The transmural voltage (VT) was not different from zero, and transmural resistance (RT) was very low, 18.3 +/- 2.0 omega.cm2 (n = 12). The basolateral membrane voltage was -80 +/- 2 mV (n = 55), and fractional apical membrane resistance was 0.92 +/- 0.23 (n = 5). Ouabain (0.1 mM) in the bath decreased basolateral membrane voltage (VB) by 23 +/- 3 mV (n = 6, P less than 0.001). Increase in K+ concentration in bath and in lumen from 5 to 50 mM decreased VB by 39 +/- 2 (n = 7, P less than 0.01) and apical membrane voltage (VA) by 10 +/- 1 mV (n = 7, P less than 0.001), respectively. Addition of 2 mM Ba2+ to bath and to lumen decreased VB by -47 +/- 2 (n = 11, P less than 0.001) and decreased VA by 8 +/- 1 mV, respectively. Reduction of HCO3- in bath from 25 to 2.5 mM decreased VB by 4 +/- 1 mV (n = 7, P less than 0.005). Reduction of bath Cl- did not cause any rapid deflection of VB. No appreciable Na+ conductance was detected in the apical membrane.(ABSTRACT TRUNCATED AT 250 WORDS)


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