scholarly journals THE IMPACT OF RELIEF ON LAND COVER AND LAND USE OF THE LLAP RIVER BASIN

2020 ◽  
Vol 14 (1) ◽  
Author(s):  
Shpejtim Bulliqi ◽  
Leutrim Krasniqi ◽  
Florim Isufi

Based on the dialectical principle, an attempt was made to analyze in details the impact of relief on land cover and land use. To achieve this objective, the Llap river basin was chosen. The Llap river basin lies in the north-eastern part of Kosovo, which is discerned as a morphological whole with particular physical-geographic elements. Since the past, relief was a factor with direct and indirect impact on land cover and especially on land use. The essential part of the analysis was the correlation of the geomorphometric parameters (altitude and slope) with land cover and land use. For calculating these parameters, a digital elevation model of 12 m / pixel was downloaded from the Alaska Satellite Facility. On the other hand, the CORINE Land Cover 2012 data from the European Environment Agency (EEA) were used for land cover. The completion of the analysis was done in that form for each category of geomorphometric parameters was compared with land cover and land use. It is evident that relief has influenced the Llap basin, both in the extent of settlements and in the activities that human develop on this land.

Hydrology ◽  
2018 ◽  
Vol 6 (1) ◽  
pp. 2 ◽  
Author(s):  
Kinati Chimdessa ◽  
Shoeb Quraishi ◽  
Asfaw Kebede ◽  
Tena Alamirew

In the Didessa river basin, which is found in Ethiopia, the human population number is increasing at an alarming rate. The conversion of forests, shrub and grasslands into cropland has increased in parallel with the population increase. The land use/land cover change (LULCC) that has been undertaken in the river basin combined with climate change may have affected the Didessa river flow and soil loss. Therefore, this study was designed to assess the impact of LULCC on the Didessa river flow and soil loss under historical and future climates. Land use/land cover (LULC) of the years 1986, 2001 and 2015 were independently combined with the historical climate to assess their individual impacts on river flow and soil loss. Further, the impact of future climates under Representative Concentration Pathways (RCP2.6, RCP4.5 and RCP8.5) scenarios on river flow and soil loss was assessed by combining the pathways with the 2015 LULC. A physically based Soil and Water Assessment Tool (SWAT2012) model in the ArcGIS 10.4.1 interface was used to realize the purpose. Results of the study revealed that LULCC that occurred between 1986 and 2015 resulted in increased average sediment yield by 20.9 t ha−1 yr−1. Climate change under RCP2.6, RCP4.5 and RCP8.5 combined with 2015 LULC increased annual average soil losses by 31.3, 50.9 and 83.5 t ha−1 yr−1 compared with the 2015 LULC under historical climate data. It was also found that 13.4%, 47.1% and 87.0% of the total area may experience high soil loss under RCP2.6, RCP4.5 and RCP8.5, respectively. Annual soil losses of five top-priority sub catchments range from 62.8 to 57.7 per hectare. Nash Stuncliffe Simulation efficiency (NSE) and R2 values during model calibration and validation indicated good agreement between observed and simulated values both for flow and sediment yield.


2018 ◽  
Vol 17 (2) ◽  
pp. 65-80
Author(s):  
Eva Stopková

The paper summarizes the geodetic contribution for the Slovak team within the joint Polish-Slovak archaeological mission at Tell el-Retaba in Egypt. Surveying work at archaeological excavations is usually influenced by somewhat specific subject of study and extreme conditions, especially at the missions in the developing countries. The case study describes spatial data development according to the archaeological conventions in order to document spatial relationships between the objects in excavated trenches. The long-term sustainability of surveying work at the site has been ensured by detailed metadata recording. Except the trench mapping, Digital Elevation Model has been calculated for the study area and for the north-eastern part of the site, with promising preliminary results for further detection and modelling of archaeological structures. In general, topographic mapping together with modern technologies like Photogrammetry, Satellite Imagery, and Remote Sensing provide valuable data sources for spatial and statistical modelling of the sites; and the results offer a different perspective for the archaeological research.


Solid Earth ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 2047-2074
Author(s):  
Oleg Sizov ◽  
Anna Volvakh ◽  
Anatoly Molodkov ◽  
Andrey Vishnevskiy ◽  
Andrey Soromotin ◽  
...  

Abstract. Analysing the genesis of Quaternary sediments is important for understanding the glaciation history and development of marine sediments in the northern part of Western Siberia. The problem is relevant since there is no consistent concept of the Quaternary sediment genesis in the north of Western Siberia. The formation of sediments is associated with marine, glacial and interglacial sedimentation conditions. The research objective is to identify the persistent features characterising the conditions of sedimentation and relief formation using the Nadym River basin as an example. The best method for studying this problem is a comprehensive analysis of the lithological, chronostratigraphic, petrographic and geomorphological studies of the Quaternary sediment upper strata. This study provides data from the analysis of the basic characteristics of quartz grains at the site. The rounding and morphology of the quartz grains provide evidence of possible glacial processing of some of the site strata. A petrographic study of selected boulder samples was performed. Some of them, by the shape and presence of striation, can be attributed to ice basins. The first use of a detailed digital elevation model applied to the study area made it possible to identify specific relief forms that could very likely be created during glaciations. Based on the analysis, we propose to consider the vast lake alluvial plains in the Nadym River basin as periglacial regions. This idea lays the lithological framework for understanding the reasons for the formation of the modern landscape structure. The materials and descriptions provided are of interest to researchers of Quaternary sediments, topography, vegetation and soil cover, particularly researchers engaged in revising the history of the natural environment development in the north of Western Siberia.


2021 ◽  
Vol 16 (3) ◽  
pp. 662-664
Author(s):  
Sabu Joseph ◽  
Rahul R ◽  
Sukanya S

The changes in the pattern of land use and land cover (LU/LC) have remarkable consequences on ecosystem functioning and natural resources dynamics. The present study analyzes the spatial pattern of LU/LC change detection along the Killiar River Basin (KRB), a major tributary of Karamana river in Thiruvananthapuram district, Kerala (India), over a period of 64 years (1957-2021) through Remote Sensing and GIS approach. The rationale of the study is to identify and classify LU/LC changes in KRB using the Survey of India (SOI) toposheet (1:50,000) of 1957, LISS-III imagery of 2005, Landsat 8 OLI & TIRS imagery of 2021 and further to scrutinize the impact of LU/LC conversion on Soil Organic Carbon stock in the study area. Five major LU/LC classes, viz., agriculture land, built-up, forest, wasteland and water bodies were characterized from available data. Within the study period, built-up area and wastelands showed a substantial increase of 51.51% and 15.67% respectively. Thus, the general trend followed is the increase in built-up and wastelands area which results in the decrease of all other LU/LC classes. Based on IPCC guidelines, total soil organic carbon (SOC) stock of different land-use types was estimated and was 1292.72 Mt C in 1957, 562.65 Mt C in 2005 and it reduced to 152.86 Mt C in 2021. This decrease is mainly due to various anthropogenic activities, mainly built-up activities. This conversion for built-up is at par with the rising population, and over-exploitation of natural and agricultural resources is increasing every year.


Author(s):  
Mohamed Elhag ◽  
Silvena Boteva

Land Cover monitoring is an essential task for a better understanding of the ecosystem’s dynamicity and complexity. The availability of Remote Sensing data improved the Land Use Land Cover mapping as it is routine work in ecosystem management. The complexity of the Mediterranean ecosystems involves a complexity of the surrounding environmental factors. An attempt to quantitatively investigate the interdependencies between land covers and affected environmental factors was conducted in Nisos Elafonisos to represent diverse and fragile coastal Mediterranean ecosystems. Sentinel-2 (MSI) sensor and ASTER Digital Elevation Model (DEM) data were used to classify the LULC as well as to draw different vegetation conditions over the designated study area. DEM derivatives were conducted and incorporated. The developed methodology is intended to assess the land use land cover for different practices under the present environmental condition of Nisos Elafonisos. Supervised classification resulted in six different land cover clusters and was tested against three different environmental clusters. The findings of the current research pointed out that the environmental variables are independent and there is a vertical distribution of the vegetation according to altitude.


Author(s):  
Ikpong Sunday Umo ◽  
M. C. Ike ◽  
Ifeanyi G. Ukwe

This study evaluates the relationships between dimensionless basin geomorphometry and discharge in the Ikpa River. The basin was stratified into seven sub-units using [1] scheme. Geospatial tools were used in generating data for the digital elevation model, while dimensionless geomorphometric parameters were generated from topographic maps (sheet 322 NE; sheet 322 SE; sheet 323 SW; and sheet 331 NW) of the basin area drawn on a scale of 1.50,000. The sampled sub-basins were gauged and discharge measured by a surface float. Graphical analysis of discharge revealed wide variations between months and in seasons across sub-basins with the rainy season attracting highest volume of discharge and the corresponding fluvial processes. The regression analysis yields a coefficient of multiple determination (R) of 0.937, signifying a very high effect expressed by 87.8 of the proportion of variance in dimensionless geomorphometric parameters on discharge in Ikpa River Basin. Also, the computed F value yields 1.439, while the Table value tested at (0.05)5/2 confident level offers 19.30. The result led to the conclusion that variations in relief ratio, average bifurcation ratio, circularity ratio, elongation ratio and form factor have a significant effect on discharge in Ikpa River Basin. This paper recommends for prompt installations of state of the art river gauging and monitoring facilities to provide the needed information to the government, researchers, and individuals for the sustainable land and watershed development options (dam and irrigation) in the coastal plain of Ikpa River basin.  


2021 ◽  
Author(s):  
Shaini Naha ◽  
Miguel A. Rico-Ramirez ◽  
Rafael Rosolem

Abstract. The objective of this study is to assess the impacts of Land Use Land Cover change on the hydrological responses of the Mahanadi river basin, a large river basin in India. Commonly, such assessments are accomplished by using distributed hydrological models in conjunction with different land use scenarios. However, these models through their complex interactions among the model parameters to generate hydrological processes, can introduce significant uncertainties to the hydrological projections. Therefore, we seek to further understand the uncertainties associated with model parameterization in those simulated hydrological responses due to different land cover scenarios. We performed a sensitivity-guided model calibration of a physically semi-distributed model, the Variable Infiltration Capacity (VIC) within a Monte Carlo Framework to generate behavioural models for subcatchments of the Mahanadi river basin. These behavioural models are then used in conjunction with historical and future land cover scenarios from the recently released, Land use Harmonisation (LUH2) to generate hydrological predictions and related uncertainties from behavioural model parameterisation. The LUH2 dataset indicates a noticeable increase in the cropland (23.3 % cover) at the expense of forest (22.65 % cover) by the end of year 2100 compared to the baseline year, 2005. As a response, simulation results indicate a median percent increase in the extreme flows (defined as the 95th percentile or higher river flow magnitude) and mean annual flows in the range of 1.8 to 11.3 % across the subcatchments. The direct conversion of forested areas to agriculture (on the order of 30,000 km2) reduces the Leaf Area Index and which subsequently reduces the Evapotranspiration (ET) and increases surface runoff. Further, the range of behavioural hydrological predictions indicated variation in the magnitudes of extreme flows simulated for the different land cover scenarios, for instance uncertainty in far future scenario ranges from 17 to 210 cumecs across subcatchments. This study indicates that the recurrent flood events occurring in the Mahanadi river basin might be influenced by the changes in LULC at the catchment scale and suggests that model parameterisation represents an uncertainty, which should be accounted for in the land-use change impact assessment.


2013 ◽  
Vol 16 (5) ◽  
pp. 989-1003 ◽  
Author(s):  
Huiliang Wang ◽  
Xuyong Li ◽  
Wenzan Li ◽  
Xinzhong Du

The Hydrologic Simulation Program-FORTRAN (HSPF) model is widely used to develop management strategies for water resources. The spatial resolution of the input data used to parameterize the HSPF model may lead to uncertainty in model outputs. In this study, we evaluated the impact of the spatial resolution of the digital elevation model (DEM) and land use data on uncertainty in HSPF-predicted flow and sediment. The resolution of DEMs can affect stream length, watershed area, and average slope, while the resolution of land use data can influence the distribution of land use information. Results showed that DEMs and land use maps with finer resolutions generated higher flow volumes and sediment loads. There was a non-linear relationship between changes in resolution of the DEM and land use data and changes in the uncertainty of predicted flow and sediment loads. Relative error was used to describe model uncertainty and the probability density function was used to estimate these uncertainties. The best-fit distributions of uncertainty in modeled flow and sediment related to DEM and land use data resolution were the generalized Pareto distribution and the Johnson SB distribution, respectively. The results of this study provide useful information for better understanding and estimating uncertainties in the HSPF model.


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