Impacts of land use changes and climate variability on transboundary Hirmand River using SWAT

Abstract Many river basins are facing a reduction of flows which might be attributed to changes in climate and human activities. This issue is very important in transboundary river basins, where already existing conflicts about shared water resources between riparian countries can easily escalate. The decrease of streamflow in the transboundary Hirmand (Helmand) River is one of the main challenges for water resources management in Iran and Afghanistan. This research aims to quantify the causes of this problem which has a direct impact on the dryness of the Hamoun wetlands being an international Ramsar site. To achieve this, the land use changes in the Middle Helmand Basin (MHB) in Afghanistan were evaluated for three time periods between 1990 and 2011 using remote sensing data and the Soil and Water Assessment Tool (SWAT) Model for understanding watershed response to environmental changes. It was concluded that the total irrigated area in the region has increased from 103,000 ha in 1990 to 122,000 ha in 2001 and 167,000 ha in 2011 (62% increase). According to the results, the average annual discharge when adapting the land use during the simulations was 4,787 million cubic meters (MCM)/year and while employing the land use of 1990 from the beginning of the simulations, the average annual discharge was 5,133 MCM/year. Therefore, the agricultural developments in the Helmand basin decreased the discharge with about 346 MCM/year accompanying an increase of 64,000 ha in an irrigated area in MHB after 1990. Notably, the impact of land use change increases significantly for more recent periods and causes a reduction of 810 MCM in annual streamflow for the MHB. The amount of water depletion (i.e. actual evapotranspiration) per hectare has increased from 5,690 in 1985 to 7,320 m3 in 2012. The applied methodology of this study is useful to cope with such a data scarcity region. It can help quantify the impact of land use change on the region and formulates strategies that can improve the situation between Iran and Afghanistan.

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Evaluating and Predicting the Effects of Land Use Changes on Hydrology in Wami River Basin, Tanzania

Hydrology ◽

10.3390/hydrology7010017 ◽

2020 ◽

Vol 7 (1) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Sekela Twisa ◽

Shija Kazumba ◽

Mathew Kurian ◽

Manfred F. Buchroithner

Keyword(s):

Land Use ◽

Water Resources ◽

Assessment Tool ◽

Swat Model ◽

Land Use Changes ◽

Management Strategies ◽

River System ◽

Least Squares Regression ◽

Natural Forests ◽

The Impact

Understanding the variation in the hydrological response of a basin associated with land use changes is essential for developing management strategies for water resources. The impact of hydrological changes caused by expected land use changes may be severe for the Wami river system, given its role as a crucial area for water, providing food and livelihoods. The objective of this study is to examine the influence of land use changes on various elements of the hydrological processes of the basin. Hybrid classification, which includes unsupervised and supervised classification techniques, is used to process the images (2000 and 2016), while CA–Markov chain analysis is used to forecast and simulate the 2032 land use state. In the current study, a combined approach—including a Soil and Water Assessment Tool (SWAT) model and Partial Least Squares Regression (PLSR)—is used to explore the influences of individual land use classes on fluctuations in the hydrological components. From the study, it is evident that land use has changed across the basin since 2000 (which is expected to continue in 2032), as well as that the hydrological effects caused by land use changes were observed. It has been found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period. These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources’ use.

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Analyzing the impacts of climate and land use changes on the water quality in the 3S river basin

Science and Technology Development Journal - Natural Sciences ◽

10.32508/stdjns.v2i2.745 ◽

2019 ◽

Vol 2 (2) ◽

pp. 125-131

Author(s):

Loi Thi Pham ◽

Khoi Nguyen Dao

Keyword(s):

Climate Change ◽

Water Quality ◽

Land Use ◽

Water Resources ◽

Land Use Change ◽

River Basin ◽

Water Resource Management ◽

Hydrological Modeling ◽

Swat Model ◽

The Impact

Assessing water resources under the influence of environmental change have gained attentions of scientists. The objective of this study was to analyze the impacts of land use change and climate change on water resources in terms quantity and quality in the 3S basin in the period 1981–2008 by using hydrological modeling (SWAT model). The results showed that streamflow and water quality (TSS, T-N, and T-P) tend to increase under individual and combined effects of climate change and land use change. In addition, the impact of land use change on the flow was smaller than the climate change impact. However, water balance components and water quality were equally affected by two factors of climate change and land use change. In general, the results of this study could serve as a reference for water resource management and planning in the river basin.

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Assessing the Impact of Climate and Land Use Change on Water Resources in Schuylkill River Watershed

10.17918/d8v387 ◽

2021 ◽

Author(s):

Suna Ekin Sahin

Keyword(s):

Land Use ◽

Water Resources ◽

Land Use Change ◽

River Watershed ◽

Schuylkill River ◽

The Impact

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The Impact of Land-Use Change on Water Resources in the Tropics: An Australian View of the Scientific Issues

Hydrology and Water Management in the Humid Tropics ◽

10.1017/cbo9780511564468.022 ◽

1993 ◽

pp. 405-413

Author(s):

P.M. Fleming

Keyword(s):

Land Use ◽

Water Resources ◽

Land Use Change ◽

The Tropics ◽

The Impact

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Link between Land Use and Flood Risk Assessment in Urban Areas

Proceedings ◽

10.3390/proceedings2019030062 ◽

2020 ◽

Vol 30 (1) ◽

pp. 62

Author(s):

Zahra Kalantari ◽

Johanna Sörensen

Keyword(s):

Land Use ◽

Land Use Change ◽

Green Infrastructure ◽

Flood Risk ◽

Urban Areas ◽

Land Use Changes ◽

Drainage System ◽

Property Owners ◽

Pluvial Flooding ◽

The Impact

The densification of urban areas has raised concerns over increased pluvial flooding. Flood risk in urban areas might increase under the impact of land use changes. Urbanisation involves the conversion of natural areas to impermeable areas, causing lower infiltration rates and increased runoff. When high-intensity rainfall exceeds the capacity of an urban drainage system, the runoff causes pluvial flooding in low-laying areas. In the present study, a long time series (i.e., 20 years) of geo-referenced flood claims from property owners has been collected and analysed in detail to assess flood risk as it relates to land use changes in urban areas. The flood claim data come from property owners with flood insurance that covers property loss from overland flooding, groundwater intrusion through basement walls, as well as flooding from drainage systems; these data serve as a proxy of flood severity. The spatial relationships between land use change and flood occurrences in different urban areas were analysed. Special emphasis was placed on examining how nature-based solutions and blue-green infrastructure relate to flood risk. The relationships are defined by a statistical method explaining the tendencies whereby land use change affects flood risk.

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Drought Risk under Climate and Land Use Changes: Implication to Water Resource Availability at Catchment Scale

Water ◽

10.3390/w11091790 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1790 ◽

Cited By ~ 1

Author(s):

Muhammad Afzal ◽

Ragab Ragab

Keyword(s):

Climate Change ◽

Land Use ◽

Water Resources ◽

Groundwater Recharge ◽

Land Use Changes ◽

Future Climate Change ◽

Emission Scenarios ◽

Catchment Scale ◽

High Emission ◽

The Impact

Although the climate change projections are produced by global models, studying the impact of climatic change on water resources is commonly investigated at catchment scale where the measurements are taken, and water management decisions are made. For this study, the Frome catchment in the UK was investigated as an example of midland England. The DiCaSM model was applied using the UKCP09 future climate change scenarios. The climate projections indicate that the greatest decrease in groundwater recharge and streamflow was projected under high emission scenarios in the 2080s. Under the medium and high emission scenarios, model results revealed that the frequency and severity of drought events would be the highest. The drought indices, the Reconnaissance Drought Index, RDI, Soil Moisture Deficit, SMD and Wetness Index, WI, predicted an increase in the severity of future drought events under the high emission scenarios. Increasing broadleaf forest area would decrease streamflow and groundwater recharge. Urban expansion could increase surface runoff. Decreasing winter barley and grass and increasing oil seed rape, would increase SMD and slightly decrease river flow. Findings of this study are helpful in the planning and management of the water resources considering the impact of climate and land use changes on variability in the availability of surface and groundwater resources.

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The assessment of surface water resources for the semi-arid Yongding River Basin from 1956 to 2000 and the impact of land use change

Hydrological Processes ◽

10.1002/hyp.7566 ◽

2010 ◽

Vol 24 (9) ◽

pp. 1123-1132 ◽

Cited By ~ 27

Author(s):

Lei Wang ◽

Zhongjing Wang ◽

Toshio Koike ◽

Hang Yin ◽

Dawen Yang ◽

...

Keyword(s):

Land Use ◽

Surface Water ◽

Water Resources ◽

Land Use Change ◽

River Basin ◽

Surface Water Resources ◽

The Impact ◽

Semi Arid ◽

Yongding River

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Changes in hydrological behaviour: case studies of the Unica and Rižana karst springs, Slovenia

10.5194/egusphere-egu2020-12961 ◽

2020 ◽

Author(s):

Natasa Ravbar ◽

Gregor Kovačič ◽

Metka Petrič

Keyword(s):

Land Use ◽

Large Scale ◽

Environmental Changes ◽

Hydrological Cycle ◽

Land Use Changes ◽

Precipitation Amount ◽

Flood Pulse ◽

Karst Springs ◽

The Impact ◽

Gauging Station

<p>Environmental changes, such as alterations in precipitation and evapotranspiration regimes, changes in vegetation type, etc. are triggering direct impact on hydrological cycle through modified amounts and patterns of recharge conditions, as well as occurrence of more frequent and severe hydrometeorological events. Karst aquifers are particularly vulnerable to these effects due to highly dynamic hydrological processes. In this study, we were interested in studying the possibilities to observe changed hydrological behaviour of karst springs on a human timescale. Therefore, we focused on two examples in Slovenia, both regionally important for freshwater supply, agriculture and hydropower. The Unica spring mostly drains areas under moderate continental climate. Its catchment has been repeatedly and severely hit by natural disasters (e.g., ice break, bark beetle attack, windthrow) after 2014 causing large-scale forest disturbances. The catchment of Ri&#382;ana spring, on the other hand, belongs to the moderate Submediterranean climate. There these types of disturbance did not occur in recent years (excluding some wildfires), but the catchment has been liable to substantial land use changes in the past six decades. For assessment of vegetation cover changes and large-scale disturbances in forests, historical digital orthophotos of the Surveying and Mapping Authority of the Republic of Slovenia since 1957 have been compared with the recent land use data provided by Ministry of Agriculture, Economy and Food and forest state database of Slovenian Forest Service. At the same time, hydrological data of the Unica (Hasberg gauging station) in the period 1962-2018 and Ri&#382;ana springs (Kubed gauging station) in the period 1966-2018 and precipitation data from Postojna (period 1962-2018) and Podgrad (period 1966-2018) meteorological stations have been processed. Individual flood pulse events over the 57 years for Unica and 53 years for Ri&#382;ana have been separated. For each flood pulse various information about precipitation amount and intensity, duration of discharge increase, its intensity and amplitude have been specified. We compared these findings with the calculated trends of meteorological and hydrological variables and also changes in land use. The impact of particular environmental change on discharge values of both springs has been evaluated, showing that both, climate and land-use changes, have considerable impact on hydrological regime of studied karst springs. In particular, altered duration of flood pulses increase, their amplitude and intensity have been observed, meaning that the most important issues of water availability that are crucial for water-dependant economic sectors are under threat.</p>

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