GIS and RS for soil loss estimation using

Research paper review

Background and Goal of paper

Thus, an attempt was made to estimate and map the spatial pattern of annual soil loss rate by water using Revised Universal Soil Loss Equation (RUSLE) simulated by GIS and Remote sensing techniques. Therefore, this research has given answers to four core research questions; how much of soil is lost per unit area of land annually in Koga watershed? How is the spatial distribution of soil loss rate in Koga watershed? Does the estimated soil loss rate exceed the tolerable limit of soil erosion set by FAO? And where are erosion hotspot areas located for conservation prioritization?

Methodology  and Results

To calculate the Soil loss in this koga watershed (KW) a Revised Universal Soil Loss Equation (RUSLE) is used , empirically expressed as

            A (metric tons ha^-1 year^-1) = L*S*R*K*C*P

where A is the mean annual soil loss (metric tons ha1 year1 ); R is the rain fall erosivity factor [MJ mm h^-1 ha^-1 year^-1]; K is the soil erodibility factor [metric tons ha^-1 MJ^-1mm^-1]; LS is the slope length–steepness factor (dimensionless); C is the cover and management factor (dimensionless, ranges from zero to one); and P is the erosion support practice or land management factor (dimensionless, and ranges from zero to one).

Raster map of each RUSLE parameters derived from different data source were produced and finally the Soil Loss Map was generated 

Reference
Soil loss estimation using GIS and Remote sensing techniques: A case of Koga watershed, Northwestern Ethiopia. H.S. Gelagay, A.S. Minale / International Soil and Water Conservation Research 4 (2016) 126–136.

Review by,

Kamran ullah Khan 

Municipal solid waste management options

Municipal solid waste (MSW) or garbage is thrown away from every house, every office, and every institute i.e. from every area that is dwelled. Topsy-turvy urbanization in the race of raising high rise & hi tech constructions far beyond the needs and closer to our egotistic fulsomeness, has lead this bare problem to a calamitous survival. The governments, environmentally sensible organizations, and inimitable individuals are finding technological ways to counter this global catastrophe. First step is to make people aware of reducing, reusing, & recycling waste at its very origin then to properly hauling it away, treating, and utilizing it in a manner that is auspicious for the environment and health of our planet.

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Waste-to-energy

A study in Malaysia shows that waste-to-energy techniques can recuperate energy from MSW [1]. MSW is being used for energy production in levelheaded countries who are putting forward a stiff scuffle to make human life better after whole world has wriggled to make it worse. In Malaysia a case study was done at a landfill to mug up the options for technological waste-to-energy stratagem. Incineration is expedient for the production of electricity & heat. Anaerobic digestion was found out to be more promised for electricity generation. A study in China showed that waste-to-energy incineration of MSW can improve ambient environment and cut out greenhouse gas emissions while producing renewable energy [2]. Pollutant discharges via MSW into land, water, & air can also be taken care of through this technology. Waste-to-energy methods can not only elicit better management of MSW but can also kindle methods of harvesting alternative energy.

Biogas yield

Biogas can be yielded from MSW using efficiently designed anaerobic digesters [3]. After adequately reducing MSW’s size and by considering key features like temperature hydrogen-ion concentration, and moisture content etc. for designing digesters, the biogas yield can be resourceful.

Bioelectricity production

A study on cattle manure shows that bioelectricity can be produced through it [4]. MSW has the potential to generate electricity that can be further utilized. Also, the greenhouse gas emissions can also be reduced when large amount of MSW will be employed for bioelectricity production [5].

MSW management in Pakistan

In Pakistan the annual MSW production is around 20 million tons and the production rate is increasing each year [6]. Unless the public is aware of environmental issues and is self-motivated to generate less waste at the source, the MSW production rate per year cannot be lessen. In the absence of proficient waste collection system the waste is being dumped on the streets and in any area that has apparently unclaimed space. Neither waste sorting at the source is encouraged nor does the public have an inner urge to do so. Serious health problems are on rise due to deteriorating environment. According to a study in Data Ganj Bukhsh Town in Lahore, Pakistan showed that reconditioning household waste material, gathering biowaste, biogasification, and energy recovery from landfill are preferable scenarios for an environmentally enhanced practice [7]. A proper MSW management plan is needed to solve the issue of solid waste floating around here and there across the country.  

A gist of MSW by,
Engr. Ayesha Alam Khurram

References

[1]        S. T. Tan, W. S. Ho et al., “Energy, economic and environmental (3E) analysis of waste-to-energy (WTE) strategies for municipal solid waste (MSW) management in Malaysia”, Energy conservation and management, vol. 102 (2015), p: 111-120.  

[2]        H. Cheng and Y. Hu, “Municipal solid waste (MSW) as a renewable source of energy: Current and future practices in China”, Bioresource Technology, vol. 101 (2010), p: 3816-3824.

[3]        A. H. Igoni, M. J. Ayotamuno et al., “Designs of anaerobic digesters for producing biogas from municipal solid-waste”, Applied Energy, vol. 85 (2008), p: 430-438.

[4]        Y. Lee and N. Nirmalakhandan, “Electricity production in membrane-less microbial fuel cell fed with livestock organic solid waste”, Bioresource Technology, vol. 102 (2011), p: 5831-5835.

[5]        M. A. Rajaeifar, H. Ghanavati et al., “Electricity generation and GHG emission reduction potentials through different municipal solid waste management technologies: A comparative

review”, Renewable and Sustainable Energy Reviews, vol. 79 (2017), p: 414-439.  

[6]      https://www.bioenergyconsult.com/solid-waste-management-in-pakistan/

[7]        S. A. Batool and M. N. Chuadhry, “The impact of municipal solid waste treatment methods on greenhouse gas emissions in Lahore, Pakistan”, Waste Management, vol. 29 (2009), p: 63-69.  

How digitization is beneficial?

Introduction

In today’s digital era, everyone in a seriatim fashion is embracing the technology to shape the career, to improve social interactions, to analyze problems, to preserve the moments, and to digitize their profile. In other words people are digitizing their lives. The process in which an analog data or information or geographic feature on a map that is not readable by computer is converted into computer readable format and represented digitally is called digitization.   

Benefits of Digitization

Once the data or map or any information is digitized its access can be increased, it can be distributed on massive scale, it can be preserved for long, it can be integrated into software, it can be analyzed in a technological way, and the intentional goals through that data can be achieved efficiently. Digital data on a simple click can be utilized, shared, updated, integrated, multiplied, copied, published, and saved. This is the reason why digital data is less likely to get stolen or get damaged for good and never to be seen again.   

Digitizing environment

It is the environment where we dwell. As we know more about the environment, we can benefit ourselves and the environment itself. Digitizing of floods can save lives. Digital flood maps provide the information to the government and to the public and make them a bit relax while making decision about new building or infrastructure or while flood proofing existing ones. Flood maps can be cost effectively used during planning and implementation of mitigation measures at flood prone localities. Digital flood maps can provide access of flood related information to land developers and managers, property owners, infrastructure planners, policy makers, and risk assessment teams.        

Similarly, digital soil map can be used for planning of crop production, understanding of ecosystem and climate change, surveying of site for construction, soil data management, integration of soil characteristics into other environmental parameters, assessment of soil degradation and vulnerability, and using soil data in forestry and agriculture. 

Digitizing healthcare

Digitizing healthcare can have enormous benefits to the doctors, care takers, patients, hospitals, and rehabilitation centers. The doctors can have access to medical condition of a patient, results of medical tests, medicine that the patient is on, allergies information, and does and don’ts with the patient. The patient won’t have to undergo similar examination repeatedly, won’t have to take same tests every now and then, and won’t have to explain same case many times, will be less tensed, and will get fast action to a particular health condition. Both parties i.e. healthcare seeker and healthcare provider will save time, money, efforts, and will enjoy peace of mind at least in the terms of accessible and assessable information. Digital data of health care will provide opportunities of better medical decisions, will be a database for real-time medical research, and will not be used against medical laws due to its openness and real-time availability.

Digitizing academics

Digital libraries have information stored and that information is accessible over a server or over the internet. The user can get the desired material without being physically present in the library and can access library 24/7 round the year. The library management can relocate, add or remove a particular material any time. The library information can be conserved and turned into various copies to lessen the fear of losing that information. There is no physical limitation to store more information after the library has set up and running. Wear and tear of books and shelves don’t affect the availability of a particular material.          

Conclusion

At this pace of fast growing digital era, there is high need to digitize offices, shops, work places, art and craft facilities, cooking and recipes, finance departments, healthcare system, planning and management firms, and academics and research etc. Digital maturity in every department requires a digital mindset, management that is equipped with digital know-how, agile techniques for analysis and decision making, and digital skilled resources and workforce.    

Digitately written by,

Engr. Ayesha Alam Khurram

Vegetation mapping using LiDAR

Introduction

LIght Detection And Ranging (LiDAR) technology is capable of making spatially located point elevation measurements to generate precise and high resolution Digital Elevation Model (DEM) of a chosen canopy or particular structure. Vegetation and trees mapping can be expertly done using LiDAR technology. LiDAR’s fast, dense, and systematic dataset permits mapping of land-use classification, vegetation canopy, ground elevations in dense vegetation covers, areas of minute textural differences, areas of minute elevation differences, and point and line features i.e. trees, water lines etc.         

Why vegetation mapping is important?

Natural resources when managed for a positive reason of saving the ecosystem in an optimistic way, can offer benefits for longer time period without getting deteriorated. Natural resources management is not comprehensive unless vegetation is properly identified with its characteristics, uses and impacts on the environment. Such vegetation mapping is sure to be efficiently done using LiDAR for determining species and groups of vegetation, measuring vegetation in three dimensions, and mapping vegetation spectrally, spatially, and temporally. If and when vegetation mapping is done in a resourceful and well-organized manner, it can solve widespread concerns during forest inventories, ecological studies, environmental modeling, hazards control, risk mapping, and wildlife safety. LiDAR data can be used to identify distinct structures in any canopy such as trees in parks, fruit orchards or forests. Distinct 3D models of trees can be created using LiDAR data. LiDAR can also acquire data on leaves’ characteristics, diversity of microhabitat, and transpiration.

Factors that effect LiDAR data

The accuracy of LiDAR data depends upon the factors like alignment of the coordinate system, quality of point data, point density, vegetation height thresholds, vegetation density in the canopy, wind that affects the leaves, leaf-on and leaf-off seasons, forest cover effects, complex vegetation cover, size of individual trees, undergrowth of herbs, shrubs’ areas, wood quality, birds in the vicinity, slope and elevation of the terrain, terrains with high and low reliefs, data recruitment times and dates, aircraft fluctuations, the distance between LiDAR sensor and trees, pulse mode, site conditions, weather, interpolation of points, stitching accuracy, and the LiDAR sensor itself. The task of creating a well-defined 3D model of tree is accomplished when the modeling of leaves, twigs, branches, tree height, tree crown, and crown diameter are incorporated into it.    

The DEM

When LiDAR data is achieved, generation of DEM can be done flawlessly after filtering of errors and outliers removal from LiDAR points, interpolating and reorganization of the points, and separation of ground points i.e. ground filtering. DEM which is representation of the landscape along with its vegetation quantitatively can be used to assess the terrain, vegetation, and trees conditions and their effects on the surroundings. DEM provides a broad vision and is used to get the spatial information about processes occurring within the forest canopy. After evaluation of DEM, the decision can be made for the management and control of vegetation areas for the betterment of neighboring flora and fauna, wildlife, water bodies, human settlement, and the vegetation itself.

Conclusion

LiDAR technology acquires accurate and workable 3D data swiftly and competently. The use of LiDAR technology in forest environments can speedily attain precise spatial data of trees and vegetation temporally. When LiDAR data is presented in form of DEM, it enables researchers to visualize the canopies’ physical, chemical, and biological scenarios through an unprecedented visualization for the quantitative analysis of the forest’s canopy.     

References

Reconstruction of individual trees based onLiDAR and in situ data 

Ground Filtering Algorithms for Airborne LiDAR Data: A Review of Critical Issues

A Vegetation Mapping Strategy for ConiferForests by Combining Airborne LiDAR Data andAerial Imagery

Analysis of the factors affecting LiDAR DTM accuracy in a steep shrub area

Written by,

Engr. Ayesha Alam Khurram

How environmental engineering can be relished with GIS?

Introduction

Geographic Information System (GIS) is one of the geospatial technologies that are enthralling the globe with their scientific stewardship and shrewdness. GIS is a deluxe technology that succors geo-mapping, environmental modeling, temporal update of the globe, achieving geographic scenarios insights, spatial data exploration, environmental data formulation, and cost analysis of the projects. GIS is suitable for every field that comes under the domain of environmental engineering. GIS gathers and saves the required environmental information which can be used to reveal selected angle of a particular situation to solve a given problem. Applications of GIS are discussed according to the location of environmental issues i.e. environmental issues that are related to air, water, and land.          

Air

The filthiness of the atmosphere can be sensed by every being living on the planet’s face. Whether it is the urbanization, the industrialization, the cottage industry advancement, or the traffic increment, it is adding more and more to the air pollution. All of it is upsetting wildlife, human life, and well being and aesthetics of the environment. GIS can be used to map the air pollution, to model the spatial configuration of the pollution, and to assess extent of the air pollution temporally. 

Water

The same factors that impact unfavorably health of the air are also offensive to the fresh water ways and water bodies. GIS can be nimbly used to inspect landscape characteristics data to evaluate water quality, collect data for assisting remediation of pollution, manage water treatment procedures, oversee natural and anthropogenic processes that disturb water catchments, make a practicable land use management plan, store spatial and temporal data of water resources, and map environmental phenomenon with in water bodies.  

Wastewater treatment can be efficiently done using GIS when it is used to calculate treatment costs, decide amongst the treatment alternatives, model wastewater transport data, improve the pumping of wastewater, and map successive treatment processes. 

Land

One of the utmost sources of environmental degradation on land is solid waste. Be it municipal, industrial or hazardous, it is totally messy. It pollutes the land, the water ways, and the atmosphere. GIS can be used to plan and map solid waste collection, segregation, transportation, and dumping system. GIS can also be used to estimate distances to landfill, map landfill location and land slope, plan optimal routes from source to disposal, and recommend a suitable disposal site.          

Conclusion

If and when the field of environmental engineering is equipped with GIS, it can sense the aptitude of GIS while making life refining environmental decisions. GIS is unequivocally an expedient and technical tool for environmental studies, applications, and research. Not only students and institutes can get benefit of this technology but also environmental decision makers, managers, developers, and even lay person can be benefited from it. GIS is expected to demonstrate more of its abilities in future there by saving money, labor, and time of its users. GIS when incorporated into environmental engineering research and projects can illustrate its technical benefits. Environmental engineering can then be understood, solved, and displayed in an enhanced style.  

References

Aspinall R, Pearson D. J Environ Manage. 2000; 59: 299–319p.

Crooks AT, Castle CJE. In Heppenstall AJ, Crooks AT, See LM, et al. (Eds). Agent–Based Models of Geographical Systems. Netherlands: Springer; 2012; 219–51p.

Goodchild MF, et al. Environmental Modeling with GIS. New York: Oxford University Press; 1993.

Written by,

Engr. Ayesha Alam Khurram