Assessment of check dams’ role in flood hazard mapping in a semi-arid environment

This study aimed to examine flood hazard zoning and assess the role of check dams as effective hydraulic structures in reducing flood hazards. To this end, factors associated with topographic, hydrologic and human characteristics were used to develop indices for flood mapping and assessment. These indices and their components were weighed for flood hazard zoning using two methods: (i) a multi-criterion decision-making model in fuzzy logic and (ii) entropy weight. After preparing the flood hazard map by using the above indices and methods, the characteristics of the change‐point were used to assess the role of the check dams in reducing flood risk. The method was used in the Ilanlu catchment, located in the northwest of Hamadan province, Iran, where it is prone to frequent flood events. The results showed that the area of ‘very low’, ‘low’ and ‘moderate’ flood hazard zones increased from about 2.2% to 7.3%, 8.6% to 19.6% and 22.7% to 31.2% after the construction of check dams, respectively. Moreover, the area of ‘high’ and ‘very high’ flood hazard zones decreased from 39.8% to 29.6%, and 26.7% to 12.2%, respectively

Geomatics in physiognomic landscape research: A Dutch view

Geomatics is a technology and service sector focussing on the acquisition, storage, analysis and management of geographically referenced information for improved decision-making. Landscape physiognomic and research –and its GI science application. The geomatics developments since 40 years confront us with many new algorithms and a variety of geo data. Due to these the interest in physiognomic research has been increased. This article links the variety of geodata and its processing functions to the landscape physiognomic research framework. This link is based on an overview of the geo data, the intended applications in landscape physiognomic research and the functions to perform. The article provides an overview of geographical data using/driving methods and applications that may support physiognomic landscape research that longs from methods that rely on geo-data that ranges from a administratively defined (INSPIRE), professional experiment acquired  up to collected by volunteers. These methods may act manifold: describe, proof and project of space as could be perceived, imagined and created from both perspectives affectively and cognitively. Besides to communicate results the methods include persistently also analysis by visualization. Other findings are the interest in changing objects of the landscape and perception via moving subjects

Participatory land management planning in biodiversity conservation areas of Lao PDR

The importance of integrating forest conservation and rural development objectives is much better understood today than in the past. Despite an increased understanding such integration in many countries remains poorly supported in terms of co-ordination between government agencies and stakeholders. Environmental degradation and loss of biodiversity conservation areas to competing alternative uses is widespread throughout the world and Lao PDR is no exception. The forest policy in Lao PDR has developed under the framework of international conventions. The protected area system has been established with the aim of conserving healthy and diverse forests. Rehabilitation and reforestation policies are important complements. The former “rules by decree” approach has been replaced by a set of laws and regulations. This thesis presents and discusses a management approach for biodiversity conservation areas in Lao PDR. As part of that, it highlights the significance of appropriate policies and legislation as a base for sustainable management, discusses various interdisciplinary and interactive planning methods tested in case studies, and analyses the utilisation of non-timber forest products as part of a strategy for sustainable management of biodiversity conservation areas. The integration of techniques from social sciences and natural sciences is emphasised to encourage local participation in managing the conservation areas. Participatory Rural Appraisal, simple sampling methods, and remote sensing were used in the studies. A simple simulation model (the Area Production Model) strengthened the inter-action process. The integrated and cross-sectoral approach turned out to be simple, flexible and dynamic. The recognition of non-timber forest products (NTFPs) plays an important role in the conservation and development of protected area management. A literature review was made to gain insight into the research trend in Southeast Asia in terms of tenure rights of NTFPs and the way people utilise them. Quantitative resource assessment is an important part in sustainable management. In a case study, a participatory two-phase sampling approach for cardamom assessment was developed and tested with a promising result

Effects of different building blocks designs on the statistical characteristics of Automated Zone-design Tool output areas

Prior to any census, the country usually gets demarcated into small geographic units called census enumeration areas, districts or blocks. In most countries, these small geographic units are also used for census dissemination. In cases where they are not used for census release, they are normally used as building blocks for developing output areas or they are aggregated to higher spatial levels in an effort to preserve privacy or confidentiality. Buildings blocks are therefore, of significant importance towards results that could be drawn from either aggregated higher level or from output areas developed using these small geographic areas. This paper aimed at evaluating the effects of different building blocks on the statistical characteristics of output areas generated using the Automated Zone-design Tool (AZTool) computer program. Different spatial layers (such as Enumeration Areas (EAs), Small Area Layers (SALs) and SubPlaces) from the 2001 census data were used as building blocks for the generation of census output areas with AZTool program in both rural and urban areas of South Africa. One way-Analysis of Variance (ANOVA) was also performed to determine statistical significance of the AZTool results. Results showed that the AZTool output areas generated from smaller areas (EAs and SALs) tend to be more homogeneous than the ones generated from larger areas (SubPlaces) when using dwelling type and geotype as homogeneity variables. The output areas from smaller areas also had narrower population distribution and more compact shapes than their counter-parts. In addition, the AZTool optimised output areas from the smaller areas allowed a clear distinction of the scale effects than output areas from larger areas. It was concluded that indeed different building blocks did have an impact on the statistical qualities of the AZTool optimised output areas in both rural and urban settings in South Africa.Keywords: AZTool; Building blocks; Enumeration areas; Output areas; Scale effects; Small Area Layers; SubPlace

Key Challenges and Potential Urban Modelling Opportunities in South Africa, with Specific Reference to the Gauteng City-Region

Urban growth and land use change models, supported by Geographic Information Systems (GIS) software and increased digital data availability, have the potential to become important tools for monitoring and guiding urban spatial planning and development. Five broad categories of urban models are utilised internationally, that is, land use transportation models, cellular automata, system dynamics, agent-based models and spatial economics/econometric models. This paper provides a broad overview of South African modelling projects that monitor or simulate urban spatial change. The review identified a variety of government and academic urban modelling initiatives. These initiatives mostly track trends, rather than simulating future scenarios, and analyse historical land cover change using GIS and remote sensing software. There is a risk within Gauteng, however, that out-dated data, different population projections, duplicated tools, limited spatial data infrastructure (SDI) and a lack of resources; could compromise urban spatial change modelling efforts within government institutions. As such, the paper discusses key challenges and opportunities for modelling urban spatial change, with specific reference to the Gauteng City-Region – the heartland of the South African economy and the Southern African region

GIS in the assessment of the impact of microclimatic variables on human comfort in Akure, Nigeria

This study involved the use of Geographic Information System (GIS) to examine variation of physiologic comfort of the people living in Akure urban environment using physiological equivalent temperature (PET) index. PET value generated from both micro-climatic parameters and thermo-physiological data measured, using Rayman model because of its ability to generate mean radiant temperature and PET which is useful in thermo-physiological heat balance model. It also examines the responses from sampled population across the land uses. Results showed that thermal heat stress are found spatially and temporally (6:00; 12:00 and 18:00 local standard time, LST) within the study area as high as (41-55) °C due to different activities in each of the land uses. Results indicated that many of the respondents are yet to have better understanding about thermal stress and it effects. The recommendation from this study is that more days of data should be measured during dry season, and planting of tress and urban greenery should be strongly encouraged as a means to improve the micro climate as well as the level of human comfort in Akure, Nigeria.Keywords: Micro-climate, Urbanization, Thermal comfort, PET, Rayma