Ecohydrology
Shafi Noor Islam; Sandra Reinstädtler; Albrecht Gnauck
Abstract
The physical characteristics of geographic location, river morphology, and the monsoon climate render Bangladesh highly vulnerable to natural disasters, primarily floods and cyclones. River flood has exerted a more significant impact on the culture, society, and economy of Bangladesh. The Ganges-Brahmaputra-Meghna ...
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The physical characteristics of geographic location, river morphology, and the monsoon climate render Bangladesh highly vulnerable to natural disasters, primarily floods and cyclones. River flood has exerted a more significant impact on the culture, society, and economy of Bangladesh. The Ganges-Brahmaputra-Meghna (GBM) river carries 2.4 billion tonnes of sediments annually, and these sediments are settled on the bed of the major rivers channel and the remaining portion carried into the Bay of Bengal. The newly emerged land in the river channel is called char or diara. Purba Khas Bandarkhola Mouza is a unique char and revenue village located in the Padma River basin. The char people and the settlements of char-lands are under threat due to floods and char-lands erosion. The Padma is a meandering river and has a high river bank and char-land erosion and accretion character in the channel. The excess water during the monsoon causes widespread flooding that damages char-land settlements, agricultural crops, infrastructures, communication networks, and livelihood. Purba Khas Bandarkhola Mouza of Char-Janajat union is highly affected by annual floods and char-lands erosion. As a result, char people have to move, and settlements have to be relocated from one place to another, within the char/or outside the char. The dwellers are displaced from the char and again come back to the native char when the new land emerges in the river channel. This study aims to develop a comprehensive plan for char-land sustainable settlement, people sustainability, and livelihood in the Padma River channel. The study is carried out based on primary and secondary data sources. The results show that the average interval of displacement is every five years at Purba Khas Bandarkhola Mouza. The cyclic dislodgment range is 90 km² ranges and pulls, and push factors are the root cause of displacement. Therefore an integrated management plan is necessary for the char-land livelihood, migration, and settlement sustainability.
Irrigation Efficiency
Mohsen Ahmadee; Morad Ghanbarpouri; Abbas Khashei Siuki; Sayed Reza Hashemi
Abstract
There has been a great need to improve agricultural yield in arid and semi-arid regions in countries like Iran due to climate conditions and poor soils quality. Zeolite, as an abundant mineral in Iran, has been proposed to be used as substitutions for chemical fertilizers to increase the yield and yield ...
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There has been a great need to improve agricultural yield in arid and semi-arid regions in countries like Iran due to climate conditions and poor soils quality. Zeolite, as an abundant mineral in Iran, has been proposed to be used as substitutions for chemical fertilizers to increase the yield and yield components of plants. In addition, magnetic water is one of the important factors to increase crop yield. For this purpose, a greenhouse study was conducted based on a factorial design by two factors (Zeolite in three types: control, calcic zeolite and potassic zeolite and water in two types: tap and magnetic) and six replications in University of Birjand, Iran. The results showed that the type of water had a significant effect on the leaf length, leaf area, root dry weight, and leaf dry weight (P-value<0.05). The type of zeolite had a significant effect on the leaf length (P-value<0.01), leaf area, and total dry weight. The interaction between water and zeolite showed a significant effect on root length and leaf width (P-value<0.05). Since the application of magnetic water with calcic zeolite had a significant effect on increasing leaf length, leaf area index, and total dry weight compared to other treatments, it is recommended to use both factors together.
Groundwater Productivity
Mushtak Ahmed Gharbi; Abdulkarem Ahmed Alalwany; Ahmed Fawzi Shfig; Saeideh Parvizi
Abstract
The present study examines the chemical properties of the groundwater in the Wadi Al-Mohammadi basin, which is located between the cities of Ramadi and Hit in the Upper Euphrates region. The study is conducted based on the field, geomorphological and geological study of the study area. The water quality ...
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The present study examines the chemical properties of the groundwater in the Wadi Al-Mohammadi basin, which is located between the cities of Ramadi and Hit in the Upper Euphrates region. The study is conducted based on the field, geomorphological and geological study of the study area. The water quality of some wells in the region was monitored during 2017, for irrigation according to the FAO Standard and their classification according to Richards. The results of the laboratory analysis showed that all of the well water under study exceeded the criteria for use of irrigation. Therefore, it is not recommended to use it in the Wadi Al-Mohammadi basin because it is saline water, where the values of electrical conductivity, which is a factor affecting agricultural use, ranged between 3.68-7.51dS/m-1 for wells 7 and 5, respectively, while the SAR ratio ranged between 7.20 - 183.6 for wells 7 and 2, respectively. Wells (5,4,1), according to Richard's chart, 1954, were classified as C4-S2, medium and very high, and wells (2,6,3,7) C4-S4, C3-S3, C4-S3, C3-S1, respectively. With continuous use, salt accumulations are formed which eventually lead to salinization of the soil and increasing the state of the problem of desertification and conversion of agricultural lands from producing to unproductive lands. In the case of its use, the methods for accuracy management intentions and selection of soil types as well as cultivation and selection of plants resistant to salinity and reducing the state of degradation of those soils within the valley should be followed. This causes increasing crop productivity.
Climate Change
Zareena Begum Irfan; A Chandhini
Abstract
Rapid urbanisation has led to emergence of urban agglomerations, which are the primary drivers of unsustainable land use trends in recent years. In terms of less restrictive laws, grazing lands are the ones that are easiest to obtain for developmental purposes. The livestock sector is also booming in ...
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Rapid urbanisation has led to emergence of urban agglomerations, which are the primary drivers of unsustainable land use trends in recent years. In terms of less restrictive laws, grazing lands are the ones that are easiest to obtain for developmental purposes. The livestock sector is also booming in terms of its production and trade because of the emergence of these agglomerations. Furthermore climate variability adds more strain on the already available grazing lands. As a result, the interplay between these factors and their resulting impact on grazing resources are a major source of concern for policy makers. The study looked at the effect of urban population density and the development of 1 million+, 5 million+, and 10 million+ agglomerations on grazing footprint for fifty countries with the highest level of permanent pasture over a period of 17 years (2000-2016). The study has also taken into consideration the livestock trade, climate variability and few other control variables to understand the true impact of the urbanisation indicators. According to the empirical findings, agglomerations of 5 million+ are the most sustainable in terms of resource usage from gazing and all other land types. However other agglomerations are quite unsustainable in their land use, necessitating stringent environmental policies to govern their land use patterns. Because of poor environmental governance in these countries, establishing comprehensive policies targeting land use and clearing is challenging.
Irrigation Efficiency
Akbar Hemmati
Abstract
Investigations have shown that the seed inoculation with rhizobium bacteria was caused higher nitrogen fixation and consequently higher grain yield of bean in dry lands. To investigate the effects of the seed inoculation with rhizobium bacteria’s strains on yield and drought resistance of common ...
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Investigations have shown that the seed inoculation with rhizobium bacteria was caused higher nitrogen fixation and consequently higher grain yield of bean in dry lands. To investigate the effects of the seed inoculation with rhizobium bacteria’s strains on yield and drought resistance of common bean, two years' study (greenhouse and field) was conducted on split plot experiment using Complete Block Design with 12 treatments in three replications 2018 and 2019 years. The experimental factors were irrigation methods 30, 60 and 80 % of soil field capacity (FC) as a main plots and four inoculants, including 54, 58, 160 and 177 rhizobia strains as a sub plots. In field the seed yield, biologic yield, irrigation water content, water use efficiency, 100seed weight, pods per plant and seed per pod were determined. In greenhouse the plant height, left area and number leaves per plant, fresh and dry tissue weight, plant nitrogen percent, nodule dry mater and nodule number per plant were determined. The results in two years’ pooled data showed that; the main effects of irrigation methods and rhizobia treatments have significant (P<0.05 %) effects on seed yield and water use efficiency. The highest yield (3066 kgha-1) and water use efficiency (0.81 kgm-3), were obtained at 60 % FC irrigation level with application of 160 strains with no significant difference with 80 % FC. The results showed that; inoculation of seed bean with rhizobium strains mitigates some of the negative effects of drought stress.
Water and Soil Conservation
Shiva Mohammadian Khorasani
Abstract
Improving water and soil productivity and its management by considering soil structure, soil textures and soil physics parameters are an important criterion for the suitable management of soil and water resources. One of the relatively new methods proposed to explain soil structure in a quantitative ...
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Improving water and soil productivity and its management by considering soil structure, soil textures and soil physics parameters are an important criterion for the suitable management of soil and water resources. One of the relatively new methods proposed to explain soil structure in a quantitative manner is the so-called fractal geometry concept. In this concept, by determining the fractal dimension of bulk soil, the stability of aggregates can be quantitatively analyzed at different scales. The objective of this study has been to quantify the soil structure stability using some classic indicators and also fractal approach in a large scale. Consequently, 41 intact soil samples were taken from an agricultural area and their particle size distribution, soil bulk density and aggregate bulk density, were measured. The weighted mean diameter and geometric mean diameter of both dry and wet aggregates were measured using the dry and wet sieving method. The fractal dimensions of all dry and wet aggregates were obtained using the fractal models of Mandelbrot, Tyler-Wheatcraft and Rieu-Sposito. The results indicated that fractal dimensions of the number-size model of Mandelbrot for dry sieve series and the number-size model of Rieu-Sposito in the wet sieve series perform quite well (R2=0.82). These two models could have the suitable determination coefficient with classical geometric mean and weighted mean diameters of aggregates (R2=0.69).
