International Research in Environment, Geography and Earth Science Vol. 8

Maritime security strategies adopted by the navy and coastguards were reviewed in the work with a view to determining spatial coverage of acquired maritime domain in the new legal regime of the exclusive economic zone. Variables applied in the assessment include the coastal resources of the state such as renewable resources like fishes and non renewable under water resources such as oil. Others include the freedom sectors such as marine traffic, pipelines, underwater cables and air traffic. In the course of the research, regression analytical tools were applied to ascertain the quality of security. Recommendations for improvement on the quality of security were then made for the region based on research output. The concepts of sea base and the sea shield concepts were reviewed as a security strategy in Nigeria’s maritime domain. Analyses of reported maritime security problems in the region were made considering the two frameworks of sea shield and sea bases. Further recommendations were then made to the advantage of the entire system. A re-engineering of the present logistics operations methodology was suggested for world’s most advanced nations involved in anti-piracy activities in the world’s maritime domains. Superiority of the security outfits of nations involved in anti-piracy activities was emphasized. A joint sea and air logistics combination was deemed to produce superior maritime effects.

Fly ashes from energy industry are a valuable raw material that can be used to remove pollutants from the leachates generated in landfills. The degree of using fly ashes received from coal combustion as a raw material to form active barriers depends mainly on the their sorption properties and ion exchange. Active barriers, as opposed to passive barriers, have capabilities to bind pollutants, which mean immobilizing them by sorption, exchange, or other chemical reactions.

The presented results concern the possibility of using fly ash from coal combustion as efficient raw material for creating active barriers able to immobilize metals contained in leachates from landfill sites. Conducted analyses of selected sorption and physicochemical properties of fly ash included, among others, Scanning Electron Microscopy (SEM-BSE), X-ray Powder Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). In addition, a thermal analysis of analyzed samples with DTA - Differential Thermal Analysis and TGA -Thermogravimetric Analysis and porosimetric analysis was conducted. Kinetics of adsorption was described based on the pseudo-first and pseudo-second order kinetic equations and intramolecular diffusion model. The release susceptibility of adsorbed Cu(II), Mn(II), Pb(II) and Zn(II) ions was set out, which determines the possibility of application of the fly ash as an permeable, active barrier in remediation of contaminated soils. The release susceptibility was determined with BCR sequential fractionation method (European Community Bureau of References – now Standards, Measurements and Testing Programme).

Air pollution has been considered the main environmental degradation agent of the planet. The major air pollution problems arise from the release of gases and particles into the atmosphere, and the main sources are vehicles and industrial activities. Different fuels are used in Brazil and there is little knowledge about the presence of organic and inorganic acids in the atmosphere of the Brazilian cities. HNO₃, HCl, HCOOH and CH₃COOH were sampled in the gas phase using passive samplers and thermodiffusion system, in which the H₂SO₄ particulate was also sampled, in five sites of Salvador. Ion chromatography analyses showed that the organic and inorganic acids measured contributed on average with 89% and 11%, respectively, to the acidity of the city's atmosphere. The strong correlations between HCOOH, CH₃COOH and HCl with CO and NO₂ indicated a common source for these compounds, predominantly from vehicular emissions. H₂SO₄ showed strong correlations with PM₁₀ and with its precursor SO₂; and HNO₃ with NO₂ and NO precursors. Most of the compounds presented negative correlations with meteorological parameters. PCA and HCA confirmed these observations. The ratios [HCOOH]/[CH₃COOH] varied from 0.69 – 1.9, typical of urban areas. Pearson's correlation analysis showed that all acids determined in this study were influenced by vehicle emissions. Important correlations were established among the studied acids, meteorological parameters and criteria air pollutants in the atmosphere of this city through PCA and HCA.

An Agro-ecological (AEZ) zone describes it’s all characteristics about those phenomena which are related with agriculture such as temperature, rainfall, humidity, soil quality, soil fertility, crop pattern of a specific region. This study was done to find out irrigation distribution, crop pattern, and a relation between them. 12 AEZ units divided in a study area on the basis of topography, soil characteristics and development possibility from H. Brammer’s research “Agroecological aspects on agricultural research of Bangladesh”. In this study, data were collected by questionnaire survey, official documents and irrigation machine's locations data were collected by using Germin eTrex 30 GPS machine and Google Earth Pro. Irrigation distribution maps were created by inserting location data into XY data input on ArcGIS 10. Comparing satellite images of different time of a year from Google earth, Crop pattern map has produced.  The result here shown in Domar upazila found 4242 irrigation machines including electric pump, diesel pump and deep tubewell and also found relation between irrigation systems and crop pattern. In findings, there mainly diesel pump used in AEZ unit 1, AEZ unit 5 and AEZ Unit 12 and these AEZ units are dominated by Potato, Maize, Groundnut, Chili and Tobacco cultivation and rest AEZ units are dominated by Boro cultivation where used deep tubewell and electric pump. By proper distribution of the irrigation machine may need less time to irrigate the same land that is irrigated by haphazardly distributed.  This research helps to compare irrigation systems of different AEZ units and ensure the proper irrigation system. Proper distribution of irrigation systems according to AEZ units improve the agricultural production and also improve the socio-economic condition. In future, for further research related to this study a researcher will get help from this study to identified crop pattern distribution, irrigation machines distribution, relation with AEZ units, crop pattern and irrigation system and application of GIS.

Development of sustainable agricultural system require cognizance of soil quality status, extent and impact of degradation processes and land use management strategy in practice. Response of soils to management and inputs are important considerations that depend on soil quality and was therefore evaluated in this study for Ultisols in subtropical China. Over-exploitation of soils over many decades has resulted in exhaustion of intensive agricultural production systems and steadily declining productivity has been noticed in long-term experiments in Asia. Changes in soil quality were assessed by measuring appropriate indicators from a long-term experiment at the Taoyuan Station, Hunan province, China from 2000 to 2009. Data obtained were analyzed using the SAS statistical package for ANOVA and means were separated with DNMRT, matched graphically to delineate threshold limits for a minimum threshold data set. Results show that the soils responded positively with Sweet potato-rape/NP+straw treatment (7.18 g kg^-1) contributing significantly (P<0.05) higher total carbon and least total carbon was contributed from Sweet potato-rape/nil fertilizer and Fallow/nil fertilizer application treatments. Highest total nitrogen was contributed by Sweet potato-rape/NP+ straw (0.882 g kg^-1) and was significantly (P<0.05) higher than each of the other treatments. Sweet potato-rape/NPK+stalk treatment also resulted in significantly higher biomass carbon (132.66 mg kg^-1) to be better biomass carbon contributors than the other treatments. Biomass nitrogen contributed by Sweet potato-rape/NPK+stalk (23.96 mg kg^-1) was also significantly higher, to be preferred over Sweet potato-rape/NPK (18.34 mg kg^-1), Sweet potato-rape/nil fertilizer (16.36 mg kg^-1) or Fallow/nil fertilizer (14.92 mgkg^-1) in contributing nitrogen into the Ultisols. This study also show that treatments with stalk amendments resulted in 3.6 to 5.7% biomass carbon and 15.8 to 23.5% biomass nitrogen increase over Sweet potato-rape/NPK. Increasing trends of biomass carbon, nitrogen and phosphorus in the Ultisols were attributed to organic matter inputs as compliment fertilizer materials. The study revealed that Sweet potato-rape/NP+straw treatment (7.18 g kg^-1) contributed significantly (P<0.05) higher total carbon, followed by Peanut-broadbean/NP+straw (6.81g kg^-1) that was significantly higher than the other treatments and least total carbon was contributed from Sweet potato-rape/nil fertilizer and Fallow/nil fertilizer  application  treatments  in  the  Ultisols.   Percent decline in potato yields were as high as 65.57% of 2007 yield value and require that further investigation be conducted to ascertain cause of this decline and forestall future yield depressions. Threshold limits for selected minimum data set for the subtropical China region Ultisols on sweet potato production was produced to enhance future soil quality monitoring in support of sustainable crop production and national food security.  

High sediment supply and low accommodation result in spit development. Spits are important   for understanding   sediment drift as well as morphodynamics of the inlets. The evolution of a diverging spit-one growing northward and another southward across the Baindur and Yadamavina River mouths along the Central West Coast of India is examined using remote sensing data, seasonal variations in the foreshore profiles, textural characteristics of the foreshore sediments, and wave-current patterns. Remote sensing data indicated lengthening of the southern spit across the Yedamavina River by 168 m between the period 1973 and 1989, while the northern spit across the Baindur River showed relative stability. Finer sediments were observed towards the ends of the spit in both northern and southern spits. Waves approach from the west between March and May, generating wave divergence and convergence cause sediment movement on either side. The alongshore current is northward from October to November and southward from December to February. This reversal in the direction of alongshore drifts, and wave divergence prevailing in this tropical climate favor  sediments movement on either side leading to diverging spits to develop. As a result of the diverging spits, both the rivers are shifting their mouths in the respective directions leading to erosion of the opposite bank. In order to prevent the erosion due to shifting of the river mouths, sediments flux to the central part of the mainland shoreline from which sediments move either side leading to spit growth needs to be checked. From the above observation, we conclude that for diverging spits to develop it is essential that there is a sediment divider, alongshore drift on either side from the divider, sediment influx, and a sheltered effect.

In the event of natural disasters, Sierra Leone like any other country loses lives as well as property and natural resources. Despite notable occurrences of small disasters in the country, only on August 14^th sugarloaf landslide and the resulting flash flood (twin disasters) which affected Regent and other communities in 2017 have captured both national and international attention due to their alarming impacts. Landslides represent a serious geologic hazard that results in loss of lives and property damages. To obtain a better knowledge on the nature of the disasters, this research considered the geological context of the landslide and focused on statistical analysis of the impacts of the twin disasters using Statistical Package for Social Sciences (SPSS). Geological field-based approach and self-administered questionnaires of both closed and open-ended questions, personal interviews and observations were adopted as research techniques. Descriptive statistics and qualitative analysis were used to analyze the data of the research. Relevant literature from books, journals, and newspapers was also consulted, including Radio, Television discussions and the internet. Slope destabilization that caused the Landslide was linked to the geology of sub-surface formation (highly weathered olivine gabbro), lineaments and the rate of weathering. Study showed remarkable economic, social and political impacts as a consequence of the twin disasters. Study also revealed that families assisted the most in both financial and non-financial ways to the victims, and renowned misappropriation of donated disaster funds. All variables tested using student t-distribution and chi-square test of independence accepted the hypothesis. Information obtained from this work could be fundamental for policy makers and development practitioners [1]. The research revealed that geological conditions played dominant role in the rainfall-triggered sugarloaf landslide underlain by fractured/jointed/bedded gabbroic rocks. Lineaments at the upper part of the slope (fault/fractures/joint sets) greatly influenced the landslide occurrence under the influence of gravity and constitute the sliding form.

The high population pressure, fast urbanization, rapid industrialization, and extensive agriculture have put great stresses on land resources, resulting into the substantial reduction in agricultural area and natural resources. Increasing population worldwide is also leading to deforestation and resource degradation that has disturbed the balance of terrestrial ecosystems. Recent studies reported that many areas covered by wastelands are decreasing because parts of wastelands are being converted into arable land. It is important to identify and monitor these changes in spatial planning and management. This paper adopts a remote sensing-based identification of culturable wastelands based on seasonal vegetation changes in Vadodara district, India. Supervised classification was applied on three MODIS images of 2016-17 of 3 different seasons. Separability analysis was applied to get the best data combination for image classification. Validation was done by ground referencing and Google earth images. The composite of winter season image with NDVI and EVI performed best with an overall accuracy of 78.2% with the kappa co-efficient of 0.7580. This method opens a possibility of using digital classification for identification of culturable wastelands in the study area which are so far mapped with visual interpretations only.

In this chapter, a Markov model to study weekly rainfall both in discrete and continuous time is presented. The model predicts and analyzes weekly rainfall pattern of  Makurdi, Nigeria using rainfall data of  eleven years(2005-2015). After some successful iterations of the discrete time Markov model, its stabilizes to equilibrium probabilities, revealing that   in the  long-run  22% of the weeks during rainy season in Makurdi, will  experience No rainfall, 50% will experience Low rainfall, 25% will experience Moderate rainfall and 2% will experience High rainfall. For the continuous time Markov model, It was observed that, if it is in No rainfall state in a given week, it would take at most 49%, 27% and 16% of the time to make a transition to Low rainfall, Moderate rainfall, and High rainfall respectively in the far future. Thus given the rainfall in a week, it is possible to determine quantitatively the probability of finding weekly rainfall in other states in the following week and in the long run. The model also reveals that, a week of High rainfall cannot be followed by another week of High rainfall,  a week of High rainfall cannot be followed by a week of  No rainfall, and a week of Moderate rainfall cannot precede a week of  High rainfall. With the combined results of the discrete and continuous time Markov model, the rainfall pattern of the study area is better understood. These results are important information to the residents of Markudi and environmental management scientists  for effective planning and viable crop production.

The quest for sustainable agriculture has increased along with the ever increasing demand for food and fibre by the growing human population. It has been realised that monoculture is probably not sustainable and has a detrimental influence on the soil’s capability to produce food and fibre. In 2010, we reported on a four year study that was conducted in the wheat producing area of the Western Cape, South Africa, in which we compared the effects of monoculture wheat to wheat in a legume/pasture rotation, with regards to soil physicochemical characteristics and culturable microbial populations. In order to determine the long-term effects of the two management systems on these parameters, the site was revisited in 2019. Soil biological aspects measured were aggregate stability, active carbon levels, microbial activity as well as carbon substrate utilisation as measured by Biolog Ecoplates^TM. Physicochemical properties measured included soil moisture on the day of sampling, as well as the levels of organic carbon, boron, sulphur and phosphorous in the soil. It was found that the carbon substrate utilisation patterns in 2019 were significantly different from those recorded in 2006. When the variables tested in 2019 were analysed, the different management systems separated clearly. Interestingly, substrate utilisation was higher in the monoculture system. This could be attributed to the possibly higher plant diversity and the associated root exudates of these systems, should the weed infestation that was occurred, be considered. Further long-term research is needed in the quest for sustainable agriculture and healthy soils.