Effect of tree evapotranspiration and hydrological processes on urban microclimate in a tropical city: A WRF/SLUCM study

It was not until the late Middle Ages that the sea penetrated far into the interior of The Netherlands, thus flooding three quarters of a million hectares of land. Since then half a million hectares have been reclaimed from the sea. The Dutch Government chose to preserve the remaining quarter of a million hectares of shallow sea with mudflats of the Waddensea as a nature reserve. The management objectives are at one hand to preserve all characteristic habitats and species with a minimal interference by human activities in geomorphological and hydrological processes, and at the other hand to guarantee the safety against the sea of the inhabitants of the adjacent mainland and islands and to facilitate certain economic and recreational uses of the Waddensea without jeopardizing the natural qualities. These objectives are being elaborated in managementplans.

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A STELLA-Based Model to Simultaneously Predict Hydrological Processes, N Uptake and Biomass Production in a Eucalyptus Plantation

Forests ◽

10.3390/f12050515 ◽

2021 ◽

Vol 12 (5) ◽

pp. 515

Author(s):

Ying Ouyang ◽

Gary Feng ◽

Heidi Renninger ◽

Theodor D. Leininger ◽

Prem Parajuli ◽

...

Keyword(s):

Water Use ◽

Biomass Production ◽

Net Primary Production ◽

N Uptake ◽

Hydrological Processes ◽

Modeling Tools ◽

Eucalyptus Plantation ◽

Simulation Scenario ◽

Use Efficiency ◽

N Use

Eucalyptus is one of the fastest growing hardwoods for bioenergy production. Currently, few modeling tools exist to simultaneously estimate soil hydrological processes, nitrogen (N) uptake, and biomass production in a eucalyptus plantation. In this study, a STELLA (Structural Thinking and Experiential Learning Laboratory with Animation)-based model was developed to meet this need. After the model calibration and validation, a simulation scenario was developed to assess eucalyptus (E. grandis × urophylla) annual net primary production (ANPP), woody biomass production (WBP), water use efficiency (WUE), and N use efficiency (NUE) for a simulation period of 20 years. Simulation results showed that a typical annual variation pattern was predicted for water use, N uptake, and ANPP, increasing from spring to fall and decreasing from fall to the following winter. Overall, the average NUE during the growth stage was 700 kg/kg. To produce 1000 kg eucalyptus biomass, it required 114.84 m3 of water and 0.92 kg of N. This study suggests that the STELLA-based model is a useful tool to estimate ANPP, WBP, WUE, and NUE in a eucalyptus plantation.

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Women Advancing Research on Hydrological Processes: Preface

Hydrological Processes ◽

10.1002/hyp.14267 ◽

2021 ◽

Author(s):

Doerthe Tetzlaff ◽

Elizabeth Boyer ◽

Tanya Doody ◽

Anne Jefferson ◽

Annalisa Molini

Keyword(s):

Hydrological Processes

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Analysis of Urban Greening Scenarios for Improving Outdoor Thermal Comfort in Neighbourhoods of Lecce (Southern Italy)

Climate ◽

10.3390/cli9070116 ◽

2021 ◽

Vol 9 (7) ◽

pp. 116

Author(s):

Elisa Gatto ◽

Fabio Ippolito ◽

Gennaro Rispoli ◽

Oliver Savio Carlo ◽

Jose Luis Santiago ◽

...

Keyword(s):

Thermal Comfort ◽

Urban Environment ◽

Southern Italy ◽

Hot Spot ◽

Outdoor Thermal Comfort ◽

Urban Greening ◽

Urban Microclimate ◽

Field Campaigns ◽

Typical Summer ◽

Radiant Temperature

This study analyses the interactions and impacts between multiple factors i.e., urban greening, building layout, and meteorological conditions that characterise the urban microclimate and thermal comfort in the urban environment. The focus was on two neighbourhoods of Lecce city (southern Italy) characterised through field campaigns and modelling simulations on a typical hot summer day. Field campaigns were performed to collect greening, building geometry, and microclimate data, which were employed in numerical simulations of several greening scenarios using the Computational Fluid Dynamics-based and microclimate model ENVI-met. Results show that, on a typical summer day, trees may lead to an average daily decrease of air temperature by up to 1.00 °C and an improvement of thermal comfort in terms of Mean Radiant Temperature (MRT) by up to 5.53 °C and Predicted Mean Vote (PMV) by up to 0.53. This decrease is more evident when the urban greening (in terms of green surfaces and trees) is increased by 1266 m2 in the first neighbourhood and 1988 m2 in the second one, with respect to the current scenario, proving that shading effect mainly contributes to improving the urban microclimate during daytime. On the contrary, the trapping effect of heat, stored by the surfaces during the day and released during the evening, induces an increase of the spatially averaged MRT by up to 2 °C during the evenings and a slight deterioration of thermal comfort, but only locally where the concentration of high LAD trees is higher. This study contributes to a better understanding of the ecosystem services provided by greening with regard to microclimate and thermal comfort within an urban environment for several hours of the day. It adds knowledge about the role of green areas in a Mediterranean city, an important hot spot of climate change, and thus it can be a guide for important urban regeneration plans.

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Impacts of land use and land cover changes on hydrological processes and sediment yield determined using the SWAT model

International Journal of Sediment Research ◽

10.1016/j.ijsrc.2021.04.002 ◽

2021 ◽

Author(s):

Edivaldo Afonso de Oliveira Serrão ◽

Madson Tavares Silva ◽

Thomás Rocha Ferreira ◽

Lorena Conceição Paiva de Ataide ◽

Cleber Assis dos Santos ◽

...

Keyword(s):

Land Use ◽

Land Cover ◽

Sediment Yield ◽

Swat Model ◽

Hydrological Processes ◽

Land Cover Changes

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Groundwater salinity variation in Upazila Assasuni (southwestern Bangladesh), as steered by surface clay layer thickness, relative elevation and present-day land use

Hydrology and Earth System Sciences ◽

10.5194/hess-23-1431-2019 ◽

2019 ◽

Vol 23 (3) ◽

pp. 1431-1451 ◽

Cited By ~ 5

Author(s):

Floris Loys Naus ◽

Paul Schot ◽

Koos Groen ◽

Kazi Matin Ahmed ◽

Jasper Griffioen

Keyword(s):

Land Use ◽

Drinking Water ◽

Coastal Region ◽

Shallow Depth ◽

Hydrological Processes ◽

Groundwater Salinity ◽

Clay Layer ◽

Fresh Groundwater ◽

Salinity Variation ◽

Clay Layers

Abstract. In the southwestern coastal region of Bangladesh, options for drinking water are limited by groundwater salinity. To protect and improve the drinking water supply, the large variation in groundwater salinity needs to be better understood. This study identifies the palaeo and present-day hydrological processes and their geographical or geological controls that determine variation in groundwater salinity in Upazila Assasuni in southwestern Bangladesh. Our approach involved three steps: a geological reconstruction, based on the literature; fieldwork to collect high-density hydrological and lithological data; and data processing to link the collected data to the geological reconstruction in order to infer the evolution of the groundwater salinity in the study area. Groundwater freshening and salinization patterns were deduced using PHREEQC cation exchange simulations and isotope data were used to derive relevant hydrological processes and water sources. We found that the factor steering the relative importance of palaeo and present-day hydrogeological conditions was the thickness of the Holocene surface clay layer. The groundwater in aquifers under thick surface clay layers is controlled by the palaeohydrological conditions prevailing when the aquifers were buried. The groundwater in aquifers under thin surface clay layers is affected by present-day processes, which vary depending on present-day surface elevation. Slightly higher-lying areas are recharged by rain and rainfed ponds and therefore have fresh groundwater at shallow depth. In contrast, the lower-lying areas with a thin surface clay layer have brackish–saline groundwater at shallow depth because of flooding by marine-influenced water, subsequent infiltration and salinization. Recently, aquaculture ponds in areas with a thin surface clay layer have increased the salinity in the underlying shallow aquifers. We hypothesize that to understand and predict shallow groundwater salinity variation in southwestern Bangladesh, the relative elevation and land use can be used as a first estimate in areas with a thin surface clay layer, while knowledge of palaeohydrogeological conditions is needed in areas with a thick surface clay layer.

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