Assessment of Reservoir Sedimentation Level and Storage Capacity Using Remotely Sensed Data for Namadope Reservoir in Luuka District, Uganda

Urban trees deliver many ecological services to the urban environment, including reduced runoff generation in storms. Trees intercept rainfall and store part of the water on leaves and branches, reducing the volume and velocity of water that reaches the soil. Moreover, trees modify the spatial distribution of rainwater under the canopy. However, measuring interception parameters is a complex task because it depends on many factors, including environmental conditions (rainfall intensity, wind speed, etc.) and tree characteristics (plant surface area, leaf and branch inclination angle, etc.). In the few last decades, remotely sensed data have been tested for retrieving tree metrics, but the use of this derived data for predicting interception parameters are still being developed. In this study, we measured the minimum water storage capacity (Cmin) and throughfall under the canopies of 12 trees belonging to three different species. All trees had their plant surface metrics calculated: plant surface area (PSA), plant area index (PAI), and plant area density (PAD). Trees were scanned with a mobile terrestrial laser scan (TLS) to obtain their individual canopy point clouds. Point clouds were used to calculate canopy metrics (canopy projected area and volume) and TLS-derived surface metrics. Measured surface metrics were then correlated to derived TLS metrics, and the relationship between TLS data and interception parameters was tested. Additionally, TLS data was used in analyses of throughfall distribution on a sub-canopy scale. The significant correlation between the directly measured surface area and TLS-derived metrics validates the use of the remotely sensed data for predicting plant area metrics. Moreover, TLS-derived metrics showed a significant correlation with a water storage capacity parameter (Cmin). The present study supports the use of TLS data as a tool for measuring tree metrics and ecosystem services such as Cmin; however, more studies to understand how to apply remotely sensed data into ecological analyses in the urban environment must be encouraged.

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A global Budyko model to partition evaporation into interception and transpiration

Hydrology and Earth System Sciences ◽

10.5194/hess-23-4983-2019 ◽

2019 ◽

Vol 23 (12) ◽

pp. 4983-5000 ◽

Cited By ~ 2

Author(s):

Ameneh Mianabadi ◽

Miriam Coenders-Gerrits ◽

Pooya Shirazi ◽

Bijan Ghahraman ◽

Amin Alizadeh

Keyword(s):

Land Surface ◽

Hydrological Cycle ◽

Remotely Sensed ◽

Global Scale ◽

Order Estimate ◽

Remotely Sensed Data ◽

Climate Conditions ◽

Total Evaporation ◽

Definition Of ◽

And Storage

Abstract. Evaporation is a crucial flux in the hydrological cycle and links the water and energy balance of a catchment. The Budyko framework is often used to provide a first-order estimate of evaporation, as it is a straightforward model with only rainfall and potential evaporation as required input. Many researchers have improved the Budyko framework by including more physics and catchment characteristics in the original equation. However, the parameterization of these improved Budyko models is not so straightforward, is data demanding, and requires local knowledge that is difficult to obtain at the global scale. In this paper we present an improvement of the previously presented Gerrits' model (“Analytical derivation of the Budyko curve based on rainfall characteristics and a simple evaporation model” in Gerrits et al., 2009 WRR), whereby total evaporation is calculated on the basis of simple interception and transpiration thresholds in combination with measurable parameters like rainfall dynamics and storage availability from remotely sensed data sources. While Gerrits' model was previously investigated for 10 catchments with different climate conditions and where some parameters were assumed to be constant, in this study we applied the model at the global scale and fed the model with remotely sensed input data. The output of the model has been compared to two complex land-surface models, STEAM and GLEAM, as well as the database of Landflux-EVAL. Our results show that total evaporation estimated by Gerrits' model is in good agreement with Landflux-EVAL, STEAM, and GLEAM. The results also show that Gerrits' model underestimates interception in comparison to STEAM and overestimates it in comparison to GLEAM, whereas the opposite is found for transpiration. Errors in interception can partly be explained by differences in the definition of interception that successively introduce errors in the calculation of transpiration. Relating to the Budyko framework, the model shows a reasonable performance for the estimation of total evaporation. The results also found a unimodal distribution of the transpiration to precipitation fraction (EtP), indicating that both increasing and decreasing aridity will result in a decline in the fraction of transpired rainfall by plants for growth and metabolism.

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Prediksi Beban Sedimentasi Waduk Selorejo Menggunakan Debit Ekstrapolasi dengan Rantai Markov

Jurnal Media Teknik Sipil ◽

10.22219/jmts.v13i1.2542 ◽

2015 ◽

Vol 13 (1) ◽

pp. 37

Author(s):

Ernawan Setyono ◽

Devi Ismijayanti

Keyword(s):

Service Life ◽

Storage Capacity ◽

Reservoir Sedimentation ◽

Sediment Storage ◽

Water Line ◽

Dead Storage ◽

Rate Of Sedimentation ◽

The Dead ◽

And Storage

Prediksi Beban Sedimentasi Waduk Selorejo Menggunakan Debit Ekstrapolasi dengan Rantai MarkovPrediction of Reservoir Sedimentation Selorejo Loads Using Debit Extrapolation Markov ChainErnawan Setyono1 & Devi Ismijayanti21,2Jurusan Teknik Sipil – Fakultas Teknik Univ. Muhammadiyah MalangAlamat Korespondensi : Jl. Raya Tlogomas 246 Malang 65144Email : 2)[email protected] reservoirs in operation since 1970 and is expected to operate and serve the needs of water up to the year 2020. The main problem encountered in the construction and operation of reservoirs is how to keep the service life of the reservoir as planned, one of which causes the sediment that settles at the bottom of the reservoir , Based on the results of recent measurements, it is known that the dead storage capacity of 1.71 million m3. Each year has an additional volume of sediment that settles that require greater storage capacity. The results showed that in 2014 increased storage capacity for additional volume of sediment that settles at 3,223,797.64 m3 and storage capacity increased to 4,933,797.64 m3. 2015 dead storage capacity increased to 7,920,967.58 m3 and continued to increase until 2020 dead storage capacity reaches 25,585,055.30 m3. This situation shows that the volume of sediment elevation has crossed the level of low-water line (LWL) and already exceeds the volume of the sediment storage capacity die before the age of reservoirs that have been planned so that it takes some effort to reduce the rate of sedimentation in the reservoir.Keywords: reservoirs, dead storage capacity, sedimentAbstrakWaduk Selorejo beroperasi sejak tahun 1970 dan diharapkan dapat beroperasi dan melayani kebutuhan air hingga pada tahun 2020. Masalah utama yang dihadapi dalam pembangunan dan pengoperasian waduk adalah bagaimana menjaga agar umur layanan waduk sesuai dengan yang direncanakan, salah satunya penyebabnya adanya sedimen yang mengendap di dasar waduk. Berdasarkan hasil pengukuran terakhir, diketahui bahwa kapasitas tampungan mati 1,71 juta m3. Setiap tahun memiliki tambahan volume sedimen yang mengendap sehingga memerlukan kapasitas tampungan yang lebih besar. Hasil penelitian menunjukkan bahwa pada tahun 2014 kapasitas tampungan meningkat karena penambahan volume sedimen yang mengendap di 3,223,797.64 m3 dan kapasitas tampungan meningkat menjadi 4,933,797.64 m3. Tahun 2015 kapasitas tampungan mati meningkat menjadi 7,920,967.58 m3 dan terus meningkat hingga 2020 kapasitas tampungan mati mencapai 25,585,055.30 m3. Situasi ini menunjukkan bahwa volume elevasi sedimen telah menyeberangi tingkat garis air rendah (LWL) dan sudah melebihi volume kapasitas tampungan sedimen mati sebelum usia waduk yang telah direncanakan sehingga dibutuhkan beberapa upaya untuk mengurangi tingkat sedimentasi ke dalam reservoir.Kata kunci: waduk, kapasitas tampungan mati, sedimen

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A global Budyko model to partition evaporation into interception and transpiration

10.5194/hess-2018-638 ◽

2019 ◽

Author(s):

Ameneh Mianabadi ◽

Miriam Coenders-Gerrits ◽

Pooya Shirazi ◽

Bijan Ghahraman ◽

Amin Alizadeh

Keyword(s):

Land Surface ◽

Hydrological Cycle ◽

Remotely Sensed ◽

Global Scale ◽

Order Estimate ◽

Remotely Sensed Data ◽

Climate Conditions ◽

Total Evaporation ◽

Surface Models ◽

And Storage

Abstract. Evaporation is a very important flux in the hydrological cycle and links the water and energy balance of a catchment. The Budyko framework is often used to provide a first order estimate of evaporation, since it is a simple model where only rainfall and potential evaporation is required as input. Many researchers have tried to improve the Budyko framework by including more physics and catchment characteristics into the original equation. However, this often resulted in additional parameters, which are unknown or difficult to determine. In this paper we present an improvement of the previously presented Gerrits' model (Analytical derivation of the Budyko curve based on rainfall characteristics and a simple evaporation model in Gerrits et al., 2009 WRR), whereby total evaporation is calculated on the basis of simple interception and transpiration thresholds in combination with measurable parameters like rainfall dynamics and storage availability from remotely sensed data sources. While Gerrits' model was investigated for 10 catchments with different climate conditions and some parameters were assumed to be constant, in this study we applied the model on the global scale and fed with remotely sensed input data. The output of the model has been compared to two complex land–surface models STEAM and GLEAM, as well as the database of Landflux-EVAL. Our results show that total evaporation estimated by Gerrits' model is in good agreement with Landflux-EVAL, STEAM and GLEAM. Results also show that Gerrits' model underestimates interception in comparison to STEAM and overestimates it in comparison to GLEAM, while for transpiration the opposite is found. Errors in interception can partly be explained by differences in the interception definition that successively introduce errors in the calculation of transpiration. Comparing to the Budyko framework, the model showed a good performance for total evaporation estimation.

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A simple global Budyko model to partition evaporation into interception and transpiration

10.5194/hess-2017-306 ◽

2017 ◽

Cited By ~ 1

Author(s):

Ameneh Mianabadi ◽

Miriam Coenders-Gerrits ◽

Pooya Shirazi ◽

Bijan Ghahraman ◽

Amin Alizadeh

Keyword(s):

Land Surface ◽

Hydrological Cycle ◽

Remotely Sensed ◽

Global Scale ◽

Order Estimate ◽

Remotely Sensed Data ◽

Climate Conditions ◽

Total Evaporation ◽

Surface Models ◽

And Storage

Abstract. Evaporation is a very important flux in the hydrological cycle and links the water and energy balance of a catchment. The Budyko framework is often used to provide a first order estimate of evaporation, since it is a simple model where only rainfall and potential evaporation is required as input. Many researchers have tried to improve the Budyko framework by including more physics and catchment characteristics into the original equation. However, this often resulted in additional parameters, which are unknown or difficult to determine. In this paper we present an improvement of the previously presented Gerrits' model (Analytical derivation of the Budyko curve based on rainfall characteristics and a simple evaporation model in Gerrits et al., 2009 WRR), whereby total evaporation is calculated on the basis of simple interception and transpiration thresholds in combination with measurable parameters like rainfall dynamics and storage availability from remotely sensed data sources. While Gerrits' model was investigated for 10 catchments with different climate conditions and also some parameters were assumed to be constant, in this study we applied the model on the global scale and it was fed with remotely sensed input data. The output of the model is compared to two complex land–surface models STEAM and GLEAM, as well as the database of Landflux-EVAL. Our results showed that total evaporation estimated by Gerrits' model is in good agreement with Landflux-EVAL, STEAM and GLEAM. Results also show that Gerrits’ model underestimated interception in comparison to STEAM and overestimated in comparison to GLEAM, while for transpiration the opposite was found. Errors in interception can partly be explained by differences in the interception definition that successively introduce errors in the calculation of transpiration. Comparing to the Budyko framework, the model showed a good performance for total evaporation estimation and the results are closer to Ol'dekop than Schreiber, Pike and Budyko curves.

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