TWO-DIMENSIONAL HYDRODYNAMIC MODELLING OF URBAN FLOOD INUNDATION CAUSED BY THE SOUTHWEST MONSOON TO CHARACTERIZE THE IMPACT OF TWENTY-YEAR DIFFERENCE IN LAND USE IN VALENZUELA-OBANDO-MEYCAUAYAN (VOM) USING FLO-2D

Abstract. The intensity of urban flooding area due to rapid urbanization in Metro Manila has been worsening over the years caused by the torrential rains brought by the Southwest Monsoon. To further characterize the impact of land use change influenced by urbanization, we compared the flood map generated from two periods (Year 200 & Year 2020) using a two-dimensional hydrodynamic modelling simulated in FLO-2D software. In our simulations, we assigned roughness coefficient values to corresponding land use category derived from an earlier study in the area previously spearhead by JICA in 2001. Each model will incorporate the implemented Year 2000 land use and the projected Year 2010 land use classification respectively, which were used in this earlier study. Meanwhile, both models will use the same sets of parameters for the simulation: IFSAR-derived DEM elevation model and a rainfall event with 10-yr return period. The area of interest of this study is located near Valenzuela-Obando-Meycauayan (VOM) with its boundaries defined from the National Mapping and Resource Information Authority. The flood simulations conducted do not take into consideration in existing flood control measures such as drainage systems and floodwalls to minimize the complexity of the model. The results are evaluated both quantitatively and qualitatively. According to the results, the impact of the land use change on flood formation in most areas are insignificant due to a low degree of land use change. However, there has been substantial impact on flooding in specific areas where there is a major change in the land use. For further studies, we recommend the use of a longer land use change period and the consideration of more varied and precise Manning’s n-values.

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Assessing the Effect of Land Use Change on Surface Runoff in a Rapidly Urbanized City: A Case Study of the Central Area of Beijing

Land ◽

10.3390/land9010017 ◽

2020 ◽

Vol 9 (1) ◽

pp. 17 ◽

Cited By ~ 7

Author(s):

Shanshan Hu ◽

Yunyun Fan ◽

Tao Zhang

Keyword(s):

Land Use ◽

Land Use Change ◽

Correlation Analysis ◽

Surface Runoff ◽

Flood Control ◽

Central Area ◽

Dominant Factor ◽

Landsat Images ◽

Rapid Urbanization ◽

The Impact

The change in land use during the process of urbanization affects surface runoff and increases flood risk in big cities. This study investigated the impact of land use change on surface runoff in Beijing’s central area during the period of rapid urbanization from 1984 to 2019. Land use maps of 1984, 1999, 2009, and 2019 were generated by image classification of Landsat images. Surface runoffs were calculated with the Soil Conservation Service curve number (SCS-CN) model. Correlation analysis was used to identify the dominant factor of land use change affecting surface runoff. The result showed that the variation trend of surface runoff was consistent with the trend of impervious land in Beijing’s central area, which increased during 1984~2009 and decreased during 2009~2019. Correlation analysis showed that changes in surface runoff were most strongly correlated with changes in impervious surfaces when compared with the correlation of runoff with other types of land use. The results of this study may provide a reference for city flood control and urban planning in fast growing cities worldwide, especially in developing countries.

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Comprehensive Assessment of the Effect of Urban Built-Up Land Expansion and Climate Change on Net Primary Productivity

Complexity ◽

10.1155/2020/8489025 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 5

Author(s):

Pengyan Zhang ◽

Yanyan Li ◽

Wenlong Jing ◽

Dan Yang ◽

Yu Zhang ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Primary Productivity ◽

Net Primary Productivity ◽

Urban Expansion ◽

Ecosystem Functions ◽

Rapid Urbanization ◽

Important Indicator ◽

The Impact

Urbanization is causing profound changes in ecosystem functions at local and regional scales. The net primary productivity (NPP) is an important indicator of global change, rapid urbanization and climate change will have a significant impact on NPP, and urban expansion and climate change in different regions have different impacts on NPP, especially in densely populated areas. However, to date, efforts to quantify urban expansion and climate change have been limited, and the impact of long-term continuous changes in NPP has not been well understood. Based on land use data, night light data, NPP data, climate data, and a series of social and economic data, we performed a comprehensive analysis of land use change in terms of type and intensity and explored the pattern of urban expansion and its relationship with NPP and climate change for the period of 2000–2015, taking Zhengzhou, China, as an example. The results show that the major form of land use change was cropland to built-up land during the 2000–2015 period, with a total area of 367.51 km2 converted. The NPP exhibited a generally increasing trend in the study area except for built-up land and water area. The average correlation coefficients between temperature and NPP and precipitation and NPP were 0.267 and 0.020, respectively, indicating that an increase in temperature and precipitation can promote NPP despite significant spatial differences. During the examined period, most expansion areas exhibited an increasing NPP trend, indicating that the influence of urban expansion on NPP is mainly characterized by an evident influence of the expansion area. The study can provide a reference for Zhengzhou and even the world's practical research to improve land use efficiency, increase agricultural productivity and natural carbon sinks, and maintain low-carbon development.

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Study on land use change and its impact on ecosystem service value –Taking Hengyang central district for example

E3S Web of Conferences ◽

10.1051/e3sconf/201911804022 ◽

2019 ◽

Vol 118 ◽

pp. 04022

Author(s):

Fuqiang Huang ◽

Zengxiang Qi

Keyword(s):

Land Use ◽

Information System ◽

Land Use Change ◽

Ecosystem Service ◽

Ecosystem Service Value ◽

Rapid Urbanization ◽

Service Value ◽

Central District ◽

Equivalent Factor ◽

The Impact

Land use change on ecosystem service value(ESV) and its interaction is significant in the rapid urbanization. The GIS(Geographic Information System) incorporating with ESV equivalent factor is used to quantitatively study the change of land use change and its impact on the ecosystem service value in Hengyang central district. Further more, the Markov model is used to predict the change of land use and ESV in 2030 under the scenario of historical trend development. The results can serve as a useful tool that assists urban planners in their evaluation of ecosystem service value under the impact of land use change.

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Rapid Urbanization Impact on the Hydrological Processes in Zhengzhou, China

Water ◽

10.3390/w12071870 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1870

Author(s):

Jingyi Wang ◽

Caihong Hu ◽

Bingyan Ma ◽

Xiaoling Mu

Keyword(s):

Land Use ◽

Urban Areas ◽

Flood Control ◽

Hydrological Process ◽

Rapid Urbanization ◽

Flood Peak ◽

Island Effect ◽

Hourly Rainfall ◽

Impact Of Urbanization ◽

The Impact

Changes in the hydrological process caused by urbanization lead to frequent flooding in cities. For fast-growing urban areas, the impact of urbanization on the hydrological process needs to be systematically analyzed. This study takes Zhengzhou as an example to analyze the impact of urbanization on the hydrological process based on 1971–2012 hourly rainfall-runoff data, combining Geographic Information Systems with traditional hydrological methods. Our study indicates that the rain island effect in different districts of city became stronger with the increase of its built-up. The uneven land use resulted in the difference of runoff process. The flood peak lag was 25–30% earlier with the change of land use. The change of flood peak increased by 10–30% with the change of built-up. The runoff coefficient increases by 20–35% with the increase of built-up, and its change increased with the change of land use. Affected by the rain island effect, precipitation tends to occur in areas where built-up is dominant, which overall magnifies the impact of urbanization on the hydrological process. This provides new ideas for urban flood control. Refine flood control standards according to regional land use changes to cope with the hydrological process after urbanization.

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Sources of and Control Measures for PTE Pollution in Soil at the Urban Fringe in Weinan, China

Land ◽

10.3390/land10070762 ◽

2021 ◽

Vol 10 (7) ◽

pp. 762

Author(s):

Lei Han ◽

Rui Chen ◽

Zhao Liu ◽

Shanshan Chang ◽

Yonghua Zhao ◽

...

Keyword(s):

Land Use ◽

Urban Expansion ◽

Pollution Sources ◽

Urban Fringe ◽

Control Measures ◽

Atomic Fluorescence Spectrometry ◽

Human Beings ◽

Rapid Urbanization ◽

Kriging Interpolation Method ◽

The Impact

The environment of the urban fringe is complex and frangible. With the acceleration of industrialization and urbanization, the urban fringe has become the primary space for urban expansion, and the intense human activities create a high risk of potentially toxic element (PTE) pollution in the soil. In this study, 138 surface soil samples were collected from a region undergoing rapid urbanization and construction—Weinan, China. Concentrations of As, Pb, Cr, Cu, and Ni (Inductively Coupled Plasma Mass Spectrometry, ICP-MS) and Hg (Atomic Fluorescence Spectrometry, AFS) were measured. The Kriging interpolation method was used to create a visualization of the spatial distribution characteristics and to analyze the pollution sources of PTEs in the soil. The pollution status of PTEs in the soil was evaluated using the national environmental quality standards for soils in different types of land use. The results show that the content range of As fluctuated a small amount and the coefficient of variation is small and mainly comes from natural soil formation. The content of Cr, Cu, and Ni around the automobile repair factory, the prefabrication factory, and the building material factory increased due to the deposition of wear particles in the soil. A total of 13.99% of the land in the study area had Hg pollution, which was mainly distributed on category 1 development land and farmland. Chemical plants were the main pollution sources. The study area should strictly control the industrial pollution emissions, regulate the agricultural production, adjust the land use planning, and reduce the impact of pollution on human beings. Furthermore, we make targeted remediation suggestions for each specific land use type. These results are of theoretical significance, will be of practical value for the control of PTEs in soil, and will provide ecological environmental protection in the urban fringe throughout the urbanization process.

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Review on Urban Heat Island in China: Methods, Its Impact on Buildings Energy Demand and Mitigation Strategies

Sustainability ◽

10.3390/su13020762 ◽

2021 ◽

Vol 13 (2) ◽

pp. 762

Author(s):

Liu Tian ◽

Yongcai Li ◽

Jun Lu ◽

Jue Wang

Keyword(s):

Energy Consumption ◽

Urban Heat Island ◽

Building Energy ◽

Design Stage ◽

Heat Island ◽

Building Energy Consumption ◽

Rapid Urbanization ◽

Substantial Impact ◽

Urban Heat ◽

The Impact

High population density, dense high-rise buildings, and impervious pavements increase the vulnerability of cities, which aggravate the urban climate environment characterized by the urban heat island (UHI) effect. Cities in China provide unique information on the UHI phenomenon because they have experienced rapid urbanization and dramatic economic development, which have had a great influence on the climate in recent decades. This paper provides a review of recent research on the methods and impacts of UHI on building energy consumption, and the practical techniques that can be used to mitigate the adverse effects of UHI in China. The impact of UHI on building energy consumption depends largely on the local microclimate, the urban area features where the building is located, and the type and characteristics of the building. In the urban areas dominated by air conditioning, UHI could result in an approximately 10–16% increase in cooling energy consumption. Besides, the potential negative effects of UHI can be prevented from China in many ways, such as urban greening, cool material, water bodies, urban ventilation, etc. These strategies could have a substantial impact on the overall urban thermal environment if they can be used in the project design stage of urban planning and implemented on a large scale. Therefore, this study is useful to deepen the understanding of the physical mechanisms of UHI and provide practical approaches to fight the UHI for the urban planners, public health officials, and city decision-makers in China.

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Dynamics of soil organic carbon in the steppes of Russia and Kazakhstan under past and future climate and land use

Regional Environmental Change ◽

10.1007/s10113-021-01799-7 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Susanne Rolinski ◽

Alexander V. Prishchepov ◽

Georg Guggenberger ◽

Norbert Bischoff ◽

Irina Kurganova ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Organic Carbon ◽

Land Use Change ◽

Soil Organic Carbon ◽

Arable Land ◽

Future Climate ◽

Future Climate Change ◽

Climate Scenarios ◽

The Impact

AbstractChanges in land use and climate are the main drivers of change in soil organic matter contents. We investigated the impact of the largest policy-induced land conversion to arable land, the Virgin Lands Campaign (VLC), from 1954 to 1963, of the massive cropland abandonment after 1990 and of climate change on soil organic carbon (SOC) stocks in steppes of Russia and Kazakhstan. We simulated carbon budgets from the pre-VLC period (1900) until 2100 using a dynamic vegetation model to assess the impacts of observed land-use change as well as future climate and land-use change scenarios. The simulations suggest for the entire VLC region (266 million hectares) that the historic cropland expansion resulted in emissions of 1.6⋅ 1015 g (= 1.6 Pg) carbon between 1950 and 1965 compared to 0.6 Pg in a scenario without the expansion. From 1990 to 2100, climate change alone is projected to cause emissions of about 1.8 (± 1.1) Pg carbon. Hypothetical recultivation of the cropland that has been abandoned after the fall of the Soviet Union until 2050 may cause emissions of 3.5 (± 0.9) Pg carbon until 2100, whereas the abandonment of all cropland until 2050 would lead to sequestration of 1.8 (± 1.2) Pg carbon. For the climate scenarios based on SRES (Special Report on Emission Scenarios) emission pathways, SOC declined only moderately for constant land use but substantially with further cropland expansion. The variation of SOC in response to the climate scenarios was smaller than that in response to the land-use scenarios. This suggests that the effects of land-use change on SOC dynamics may become as relevant as those of future climate change in the Eurasian steppes.

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