Mapping of water-related ecosystem services in the uMngeni catchment using a daily time-step hydrological model for prioritisation of ecological infrastructure investment – Part 2: Outputs

South Africa is a semi-arid country which frequently faces water shortages, and experienced a severe drought in the 2016 and 2017 rainfall seasons. Government is under pressure to continue to deliver clean water to the growing population at a high assurance of supply. Studies now show that the delivery of water may be sustained not only through built infrastructure such as dams and pipelines, but also through investment in ecological infrastructure (EI). Part 1 of this paper in 2 parts concentrated on the role of EI in delivering water-related ecosystem services, as well as the motivation for this study, and the methods used in modelling and mapping the catchment. Part 2 explores and illustrates the current level of delivery of water-related ecosystem services in different parts of the catchment, with potential hydrological benefits of rehabilitation and protection of EI in the uMngeni catchment. The Mpendle, Lions River, Karkloof, Inanda and Durban sub-catchments are important areas for the generation of streamflows which accumulate downstream (i.e. water yield in the catchment) when annual totals are considered. Modelled annual sediment yield (in tonnes) from naturally vegetated areas is most severe in the lower catchment areas with steeper slopes such as Inanda, and in the high-altitude areas which have both steeper slopes and higher rainfall. The central and eastern parts of the uMngeni catchment were found to contribute the greatest yield of sediment from degraded areas with low protective vegetation cover. This combined modelling and mapping exercise highlighted areas of priority ecosystem service delivery, such as higher altitude grassland areas, which could be recommended for formal conservation, or protection under private partnerships. Generally, these areas confirm the intuitive sense of catchment stakeholders, but provide a robust and more defendable analysis through which water volumes are quantifiable, and potential investment into catchment interventions are justified.

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Mapping of water-related ecosystem services in the uMngeni catchment using a daily time-step hydrological model for prioritisation of ecological infrastructure investment – Part 1: Context and modelling approach

Water SA ◽

10.4314/wsa.v44i4.07 ◽

2018 ◽

Vol 44 (4 October) ◽

Author(s):

CJ Hughes ◽

G De Winnaar ◽

RE Schulze ◽

M Mander ◽

GPW Jewitt

Keyword(s):

Ecosystem Services ◽

Hydrological Model ◽

Severe Drought ◽

Water Shortages ◽

Time Step ◽

Ecological Infrastructure ◽

High Assurance ◽

Daily Time Step ◽

Daily Time

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ESTIMASI HASIL AIR DARI DAERAH TANGKAPAN AIR DANAU RAWA PENING DENGAN MENGGUNAKAN MODEL INVEST

MAJALAH ILMIAH GLOBE ◽

10.24895/mig.2017.19-2.578 ◽

2017 ◽

Vol 19 (2) ◽

pp. 157

Author(s):

Nunung Puji Nugroho

Keyword(s):

Spatial Distribution ◽

Ecosystem Services ◽

Water Resources ◽

High Water ◽

Water Yield ◽

Accurate Information ◽

Yield Model ◽

Catchment Areas ◽

Integrated Valuation ◽

Valuation Of Ecosystem Services

ABSTRAKInformasi hasil air dari suatu ekosistem sangat penting dalam pengelolaan sumber daya air. Dalam perencanaan kegiatan konservasi sumber daya air, informasi sebaran spasial hasil air diperlukan untuk menentukan prioritas wilayah terkait dengan alokasi anggaran. Hasil air dari suatu ekosistem atau daerah aliran sungai (DAS) dapat diestimasi dengan menggunakan model hidrologi. Penelitian ini bertujuan untuk mendapatkan informasi tentang hasil air, baik besaran maupun sebaran spasialnya, dari daerah tangkapan air (DTA) Danau Rawa Pening. Hasil air dari lokasi penelitian dihitung dengan menggunakan model hasil air pada InVEST (the Integrated Valuation of Ecosystem Services and Tradeoffs), yang didasarkan pada pendekatan neraca air. Hasil perhitungan menunjukkan bahwa volume hasil air di DTA Danau Rawa Pening pada tahun 2015 adalah sekitar 337 juta m3. SubDAS Galeh, sebagai subDAS terluas, merupakan penghasil air terbesar (72,4 juta m3) diikuti oleh subDAS Sraten (66,8 juta m3) dan Parat (62,4 juta m3). Secara spasial, hasil air di lokasi kajian mempunyai nilai antara 0 hingga 29.634,19 m3/ha. Wilayah hulu dan tengah subDAS Sraten secara umum mempunyai hasil air yang lebih tinggi, sedangkan wilayah danau dan sekitarnya serta hulu subDAS Galeh mempunyai hasil air yang lebih rendah dibandingkan dengan wilayah lainnya. Wilayah dengan hasil air tinggi dapat diprioritaskan dalam kegiatan konservasi sumber daya air untuk mendukung pasokan air ke Danau Rawa Pening.Kata kunci: hasil air, daerah tangkapan air, model InVEST, Danau Rawa PeningABSTRACTAccurate information on water yield from an ecosystem is very important in the management of water resources. In the planning of water resources conservation activities, the information on the spatial distribution of water yield is needed to determine regional priorities related to budget allocations. The water yield from an ecosystem or watershed can be estimated using a hydrological model. This study aimed to obtain information about the water yield, both the magnitude and their spatial distribution, from the catchment areas of Lake Rawa Pening. The water yield from the study area was calculated using the water yield model in InVEST (the Integrated Valuation of Ecosystem Services and Tradeoffs), which based on the water balance approach. The results indicated that the volume of water yield in Lake Rawa Pening for 2015 is approximately 337 million m3. Galeh subwatershed, as the largest subwatershed, is the largest water producer (72.4 million m3), followed by Sraten subwatershed (66.8 million m3) and Parat subwatershed (62.4 million m3). Spatially, the water yield at the study site has a value between 0 to 29,634.19 m3/ha. Upstream and middle areas of Sraten subwatershed generally have higher water yield, while the lake and its surrounding areas as well as the upstream of Galeh subwatershed have lower water yield compared to other regions. The regions with high water yield can be prioritized in water resource conservation activities to support the supply of water to Lake Rawa Pening.Keywords: water yield, catchment areas, InVEST model, Lake Rawa Pening

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Runoff modelling in glacierized Central Asian catchments for present-day and future climate

Hydrology Research ◽

10.2166/nh.2006.0008 ◽

2006 ◽

Vol 37 (2) ◽

pp. 93-105 ◽

Cited By ~ 48

Author(s):

W. Hagg ◽

L.N. Braun ◽

M. Weber ◽

M. Becht

Keyword(s):

Tien Shan ◽

Water Shortages ◽

Time Step ◽

Climate Conditions ◽

Central Asian ◽

Complex Picture ◽

Daily Time Step ◽

The Alps ◽

High Degree ◽

Tien Shan Mountains

A conceptual precipitation–runoff model was applied in five glacierized catchments in Central Asia. The model, which was first developed and applied in the Alps, works on a daily time step and yields good results in the more continental climate of the Tien Shan mountains for present-day climate conditions. Runoff scenarios for different climates (doubling of CO2) and glacierization conditions predict an increased flood risk as a first stage and a more complex picture after a complete glacier loss: a higher discharge during spring due to an earlier and more intense snowmelt is followed by a water deficiency in hot and dry summer periods. This unfavourable seasonal redistribution of the water supply has dramatic consequences for the Central Asian lowlands, which depend to a high degree on the glacier melt water for irrigation and already nowadays suffer from water shortages.

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Benefits of water-related ecological infrastructure investments to support sustainable land-use: a review of evidence from critically water-stressed catchments in South Africa

Royal Society Open Science ◽

10.1098/rsos.201402 ◽

2021 ◽

Vol 8 (4) ◽

Author(s):

Alanna J. Rebelo ◽

Petra B. Holden ◽

Karen Esler ◽

Mark G. New

Keyword(s):

Land Use ◽

Ecosystem Services ◽

South African ◽

Evidence Base ◽

Sustainable Land Use ◽

Financial Investment ◽

Ecological Infrastructure ◽

Catchment Areas ◽

Infrastructure Investments

Investments to promote sustainable land-use within critical river catchment areas are often undertaken to provide benefits to society. Investments generally aim to protect or restore ecological infrastructure—the underlying framework of ecosystems, functions and processes that supply ecosystem services—for multiple benefits to society. However, the empirical evidence base from studies across the world on both mechanisms and outcomes to support these assumptions is limited. We collate evidence on the benefits of ecological infrastructure interventions, in terms of ecosystem services provided to society, from three major South African water-providing catchments using a novel framework. In these catchments, millions of US Dollars' worth of investments have been made into ecological infrastructure since 1996. We ask the question: is there evidence that ecological infrastructure interventions are delivering the proposed benefits? Results show that even in catchments with substantial, long-term financial investment into ecological infrastructure, research has not empirically confirmed the benefits. Better baseline data collection is required, and monitoring during and after ecological infrastructure interventions, to quantify benefits to society. This evidence is needed to leverage investment into ecological infrastructure interventions at scale. Investment at scale is needed to transition to more sustainable land-use to unlock greater benefits to nature and people.

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Assessment of the Impacts of Climate and LULC Changes on the Water Yield in the Citarum River Basin, West Java Province, Indonesia

Sustainability ◽

10.3390/su13073919 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3919

Author(s):

Irmadi Nahib ◽

Wiwin Ambarwulan ◽

Ati Rahadiati ◽

Lestari Munajati ◽

Yosef Prihanto ◽

...

Keyword(s):

Ecosystem Services ◽

River Basin ◽

Potential Evapotranspiration ◽

Soil Depth ◽

Coefficient Of Determination ◽

Water Yield ◽

West Java ◽

Catchment Areas ◽

Integrated Valuation ◽

Valuation Of Ecosystem Services

Changes in climate and land use land cover (LULC) are important factors that affect water yield (WY). This study explores which factors have more significant impact on changes in WY, spatially and temporally, within the Citarum River Basin Unit (RBU), West Java Province, Indonesia with an area of ±11.317 km2. The climate in the area of Citarum RBU belongs to the Am climate type, which is characterized by the presence of one or more dry months. The objectives of the study were: (1) To estimate a water yield model using integrated valuation of ecosystem services and tradeoffs (InVEST), and (2) to test the sensitivity of water yield (WY) to changes in climate variables (rainfall and evapotranspiration) and in LULC. The integration of remote sensing (RS), geographic information system (GIS), and the integrated valuation of ecosystem services and tradeoffs (InVEST) approach were used in this study. InVEST is a suite of models used to map and value the goods and services from nature that sustain and fulfill human life. The parameters used for determining the WY are LULC, precipitation, average annual potential evapotranspiration, soil depth, and plant available water content (PAWC). The results showed that the WY within the territory of Citarum RBU was 12.17 billion m3/year, with mean WY (MWY) of 935.26 mm/year. The results also show that the magnitude of MWY in Citarum RBU is lower than the results obtained in Lake Rawa Pening Catchment Areas, Semarang Regency and Salatiga City, Central Java (1.137 mm/year) and in the Patuha Mountain region, Bandung Regency, West Java (2.163 mm/year), which have the same climatic conditions. The WY volume decreased from 2006, to 2012, and 2018. Based on the results of the simulation, climatic parameters played a major role affecting WY compared to changes in LULC in the Citarum RBU. This model also shows that the effect of changes in rainfall (14.06–27.53%) is more dominant followed by the effect of evapotranspiration (10.97–23.86%) and LULC (10.29–12.96%). The InVEST model is very effective and robust for estimating WY in Citarum RBU, which was indicated by high coefficient of determination (R2) 0.9942 and the RSME value of 0.70.

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Water Availability In Patuha Mountain Region Using InVEST Model “Hydropower Water Yield”

E3S Web of Conferences ◽

10.1051/e3sconf/201912501015 ◽

2019 ◽

Vol 125 ◽

pp. 01015

Author(s):

Yudistiro ◽

Eko Kusratmoko ◽

Jarot Mulyo Semedi

Keyword(s):

Ecosystem Services ◽

High Volume ◽

Mountain Region ◽

Water Yield ◽

Mountainous Area ◽

Yield Model ◽

Invest Model ◽

Catchment Areas ◽

Lowland Area ◽

Integrated Valuation

The mountainous region provides ecosystem services for the surrounding area and its lowland area. Patuha Mountain Region located in Ciwidey, Rancabali and Pasirjambu district of Bandung Regency. Fast population growth causing the need for water to increase drastically. The water yield from an ecosystem or watershed can be estimated using a hydrological model. This study aimed to estimate water yield, both the magnitude and their spatial distribution of the Patuha Mountain catchment areas. The water yield from the study area was calculated using the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) water yield model, which based on the water balance approach. The results indicated that the volume of water yield in Patuha Mountain for 2018 has a value between 21.429 to 31.857 m3/ha/year and approximately 1.202 million m3 per year. Spatially, sub-watersheds with a high volume of Water yield located in the southeast of Patuha Mountain, which is a mountainous area with an elevation of more than 1.500 m above sea level and rainfall average of 2.500 to 3300 mm per year. The water yield area also shows the same pattern with the distribution of the rainfall area.

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Hydrologic Modeling Using SWAT

Advances in Environmental Engineering and Green Technologies - Decision Support Methods for Assessing Flood Risk and Vulnerability ◽

10.4018/978-1-5225-9771-1.ch008 ◽

2020 ◽

pp. 162-198 ◽

Cited By ~ 2

Author(s):

Zineb Moumen ◽

Soumaya Nabih ◽

Ismail Elhassnaoui ◽

Abderrahim Lahrach

Keyword(s):

Land Management ◽

Swat Model ◽

Management Strategies ◽

Rainfall Event ◽

Decision Makers ◽

Water Yield ◽

Flood Forecast ◽

Time Step ◽

Daily Time Step ◽

Flood Damages

The Innaoune Watershed represents an important hydric potential of the oriental part of Morocco. However, the basin exhibits a set of hydrologic drawbacks, such as floods, erosion, and pollution. This chapter is focused on flood forecast study. In order to help managers and decision makers to adopt the appropriate land management strategies for protecting the population from flood damages, the study of the hydrological behavior and quantification of water yield are paramount. According to this perspective, the main goal of this chapter is to test the ability of the SWAT model to simulate and reproduce the hydrological behavior of the upstream of Innaouene Watershed. The output of the model could be used to map, delineate, and forecast the floods expansion for a particular rainfall event. SWAT was performed on a daily time step from 2004 to 2012 for calibration and 2012 to 2014 for validation. The model accuracy was evaluated by measuring the Nash-Sutcliffe coefficient and R2.

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ASSESSMENT OF MAXIMUM INSTANT DISCHARGE OF VARIOUS FREQUENCY AT UNGAUGED MOUNTAINOUS RIVER KHEMCHIK (TUVA REPUBLIC) BASED ON MATHEMATICAL MODELLING

Engineering survey ◽

10.25296/1997-8650-2019-13-2-36-51 ◽

2019 ◽

Vol 13 (2) ◽

pp. 36-51 ◽

Cited By ~ 2

Author(s):

O. M. Makarieva ◽

N. V. Nesterova ◽

G. P. Yampolsky ◽

E. Y. Kudymova

Keyword(s):

Coniferous Forest ◽

Frequency Interval ◽

Time Step ◽

Model Calculations ◽

Runoff Formation ◽

Emergency Situations ◽

Daily Streamflow ◽

Standard Methodology ◽

Maximum Elevation ◽

Daily Time Step

Abstract: the article presents the results of application of distributed deterministic hydrological model Hydrograph for estimation of maximum discharge values of different frequency at the ungauged catchment of the Khemchik River (Khemchik village, Tuva Republic). The catchment area is 1750 km2 , the average and maximum elevation — 2200 and 3600 m, respectively. Due to the lack of detailed information, a schematization of the catchment and the parameterization of the model are proposed, based on general ideas about the water balance and the processes of runoff formation of the main landscapes — rocky talus, coniferous forest and steppe. Parameters and algorithms are verified based on the results of streamflow modeling at two studied catchments: the Tapsy River — Kara-Khol (302 km2 ) and the Khemchik River — Iyme (25500 km2 ). Modelling of runoff formation processes with daily time step for the Khemchik River — Khemchik village was conducted for the period 1966–2012 using observational data at Teeli meteorological station. For the transition from daily to instant discharges, the dependence of the observed values of instant and daily streamflow at the studied gauges has been applied. On the basis of simulated discharge series, the frequency curve was built and the obtained curve was compared with the calculation data according to the standard methodology SP 33-101-2003 “Determination of the main calculated hydrological characteristics” using the analogue river. Simulated maximum instant discharges for entire frequency interval of up to 1% are 1.3–5 times higher than the values obtained by standard methodology SP 33-101-2003. The results of model calculations is indirectly confirmed by the evidences of regular flooding of the Khemchik village provided by the Ministry of Emergency Situations of the Tuva Republic, which is not predicted by the values obtained by the standard methods.

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A 2050 Vision for Colorado's water supply future

Water Practice & Technology ◽

10.2166/wpt.2012.095 ◽

2012 ◽

Vol 7 (4) ◽

Author(s):

N. Rowan ◽

E. Hecox ◽

S. Morea

Keyword(s):

Water Supply ◽

Water Conservation ◽

Colorado River ◽

Economic Recession ◽

The State ◽

Severe Drought ◽

Water Shortages ◽

Water Projects ◽

Demand And Supply ◽

Local Water

The last decade has brought many changes to Colorado's water supply outlook. Despite the recent economic recession, the state has experienced significant population growth, and Colorado's population is expected to nearly double within the next 40 years. Other pressures on Colorado's water supply include severe drought, a desire to meet multiple needs (i.e., municipal, environmental, recreational) with existing resources, and impacts to agriculture due to water shortages, urbanization, and transfers to new users. To address these challenges, the Colorado Water Conservation Board (CWCB) has undertaken a visioning process to explore solutions to these future water supply challenges. As part of this process, CWCB has led the state in identifying demand and supply strategies to meet the state's future water needs while considering agriculture and the environment. These strategies have been combined into varying portfolios that include methods such as conservation, local water projects, new Colorado River development, and agricultural transfers. This paper details the development and evaluation of these portfolios and describes stakeholder's efforts to balance meeting Colorado's water needs in the future.

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Study on the Comprehensive Improvement of Ecosystem Services in a China’s Bay City for Spatial Optimization

Water ◽

10.3390/w13152072 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2072

Author(s):

Ying Fang ◽

Tianlin Zhai ◽

Xiaodong Zhao ◽

Kun Chen ◽

Baishu Guo ◽

...

Keyword(s):

Ecosystem Services ◽

Carbon Sequestration ◽

Ecosystem Service ◽

Food Supply ◽

Spatial Optimization ◽

Coastal Areas ◽

Water Yield ◽

Human Welfare ◽

Yantai City ◽

Synergistic Relationships

Ecosystem services are characterized by region and scale, and contribute to human welfare. Taking Yantai city, a typical bay city in China, as the example, its three representative ecosystem services: food supply (FS), carbon sequestration (CS) and water yield (WY) were chosen as study targets. Based on analyzation of six different aspects of the supply and variation characteristic of demand, this study tried to propose advices for comprehensive improvement of ecosystem services for spatial optimization. The results showed that: (1) ecosystem services supply was strong in central and southern areas of Yantai, while the northern coastal areas were relatively weak; (2) synergistic relationships were found of FS-CS, FS-WY and CS-WY both in 2009 and 2015, with the strongest one for FS-WY. Additionally, in the synergistic relationships, each pair of ecosystem services was dominated by one ecosystem service; (3) most of the three pairs of synergistic relationships had the tendency to strengthen with larger scales; (4) four ecosystem demands changing areas were observed and comprehensive improvement suggestions for them were proposed. This work provides a new attempt to improve ecosystem services based on its supply-demand relationship, which will give a baseline reference for related studies in Yantai city, as well as other similar bay cities.

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