| 1. |
- Abbas, Nahlah, et al.
(författare)
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Recent Trends and Long-Range Forecasts of Water Resources of Northeast Iraq and Climate Change Adaptation Measures
- 2018
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Ingår i: Water. - Switzerland : MDPI. - 2073-4441. ; 10:11, s. 1-19
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Tidskriftsartikel (refereegranskat)abstract
- Iraq has been experiencing water resources scarcity, and is vulnerable to climate change. Analysis of historical data revealed that the region is experiencing climate change to a degree higher than generally reported elsewhere. The relationship between climate change and its effect on water resources of a region has been sparsely addressed in published literature. To fill that gap this research work first investigates if there has been a significant change in climate in the region, which has been found to be true. In the next stage, the research projects future climatic scenarios of the region based on six oft-used General CirculationModel (GCM) ensembles, namely CCSM4, CSIRO-Mk3.6.0, GFDL-ESM2M, MEROC5, HadGEM2-ES, and IPSL-CM5A-LR. The relationship between climate change and its impact on water resources is explored through the application of the popular, widely used SWAT model. The model depicts the availability of water resources, classified separately as blue and green waters, for near and distant futures for the region. Some of the findings are foreboding and warrants urgent attention of planners and decision makers. According to model outputs, the region may experience precipitation reduction of about 12.6% and 21% in near (2049–2069) and distant (2080–2099) futures, respectively under RCP8.5. Those figures under RCP4.5 are 15% and 23.4%, respectively and under RCP2.6 are 12.2% and 18.4%, respectively. As a consequence, the blue water may experience decreases of about 22.6% and 40% under RCP8.5, 25.8% and 46% under RCP4.5, and 34.4% and 31% under RCP2.6 during the periods 2049–2069 and 2080–2099, respectively. Green water, by contrast, may reduce by about 10.6% and 19.6% under RCP8.5, by about 14.8% and 19.4% under RCP4.5, and by about 15.8% and 14.2% under RCP2.6 during the periods 2049–2069 and 2080–2099, respectively. The research further investigates how the population are adapting to already changed climates and how they are expected to cope in the future when the shift in climate is expected to be much greater.
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| 2. |
- Abbas, Nahlah, et al.
(författare)
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The Impacts of Sea Level Rise on Basrah City,Iraq : The Impacts of Sea Level Rise on Basrah City,Iraq
- 2020
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Ingår i: Open Journal of Geology. - USA : Scientific Research Publishing. - 2161-7570 .- 2161-7589. ; 10:12, s. 1189-1197
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Tidskriftsartikel (refereegranskat)abstract
- Sea Level Rise (SLR) above the Mean Sea Level (MSL) is more likely to cause a significant risk to the coastal regions. This research explores the potential impact of sea level rise, due to climate change, on coastal areas. It examines the impact of sea level rise on Basrah city and adjacent cities in Iraq. A digital elevation model (DEM) was used to create a model of Potentially Inundated Areas, manipulated and processed in Geographical Information System version 10.7 (ArcGIS 10.7). Through this model, the impact of sea level rise was assessed on the surface area. After the susceptible areas were delineated, it was estimated that at worst case scenario of 5 m sea level rise will impact Basrah city by losing 38 percent of its total surface area.
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| 3. |
- Abbas, Nahla, et al.
(författare)
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Water resources problems of Iraq: Climate change adaptation and mitigation
- 2018
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Ingår i: Journal of Environmental Hydrology. - : International Association for Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 26
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Tidskriftsartikel (refereegranskat)abstract
- Iraq is suffering from water scarcity, and future predictions indicate that it could get worse due to changing climate. Arguably, climate change is one of the greatest challenges onfronting this region it could have significant adverse effects on water resources and hence the environment and economy, particularly in the agricultural sector. This study considers possible adaptation and mitigation measures that could be undertaken in response to climate change. To overcome this problem,adaptation measures at farm and government level were conferred. Farm-level adaptation comprises adopting crop modification, soil conservation, irrigation, changing crop calendar and planting of trees. The government role is to ensure success of these adaptation measures. The government should get involved and support the farmers financially and technologically.
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| 4. |
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| 5. |
- Ahmed, Nur, et al.
(författare)
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Impact of climate change on rice insect pests and their natural enemies
- 2013
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Konferensbidrag (refereegranskat)abstract
- Rice is one of the important staple foods for half of the world population particularly Asian countries for their livelihood, socio-economic and nutrition. Global warming is predicted to increase frequency of precipitation/rainfall, intensity of drought and solar-radiation/UV-B radiation which might affect the intensity and severity of rice pests in one hand, but also change in other friendly arthropods on the other hand. The present studies discuss the influence of climatic factors (temperature and rainfall) on yellow stem borer (YSB), brown planthopper (BPH), green leafhopper (GLH) and their natural enemies (spider, lady bird beetle, green mirid bug). Light trap and sweep net catches of arthropods from different rice habitats were used in this study. For GLH there is a strong periodicity at 6 months and a somewhat weaker periodicity at 12 months followed by an even weaker periodicity at 3 months, especially valid for both methods of data collection (light trap and sweep-net data). Finally, for GMB there is a strong periodicity at 6 months and a somewhat weaker periodicity at 3 months followed by an even weaker periodicity at 4 months. There is a general increasing trend over the ten years seems to be present in the GLH. This corresponds to that the abundance in 2005 is generally 15 times larger than in January 1996. For LBB, there is an increasing trend of log abundance of LBB over time and shows a strong periodicity at 3 months and a somewhat weaker periodicity at 4 months followed by an even weaker periodicity at about 6 months. For Spider there is a strong periodicity at 2.4 months and a somewhat weaker periodicity at 4 months followed by an even weaker periodicities at about 3 months and 6 months. Results show an increase of maximum temperature of approximately 0.5 to 1°C over 10 years.
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| 6. |
- Ali, Md Panna, et al.
(författare)
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Farmer's behavior in pesticide use : Insights study from smallholder and intensive agricultural farms in Bangladesh
- 2020
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697. ; 747
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Tidskriftsartikel (refereegranskat)abstract
- Since independence and over the years, pesticides have become a dominant feature of Bangladesh agriculture. To protect farmers' health, environment and to improve sustainability of chemical pest control quantitative understanding of farmers' behavior in pesticide use is critical. However, study on the levels of knowledge and awareness of farmers and the practices of pesticide use are often limited. We conducted a broad analysis on the effects of knowledge and awareness of farmers as well as the influence of the different associated stakeholders such as pesticide retailers and the government, on farmers' behavior in pesticide use from a detailed survey of 917 agricultural households in different regions of Bangladesh. Within eight protective behaviors (PBs) or PPEs were largely influenced by the crops growers and regions. Never discarding empty pesticide containers in the field, never applying pesticides more than prescribed by DAE or the instruction manual, selecting new types of pesticides recommended by DAE and purchasing low toxicity pesticides were the most adopted practices. Most farmers from the South-East region were adopting the PB of wearing mask, gloves and long sleeved clothes when spraying and farmers from South trusted the recommendations of pesticides by village leaders and neighbors. Majority of vegetables growers were well informed that pesticides were very harmful to the quality of agricultural products, the environment, and human health but not rice or mixed crops growers. Generally, PBs were positively affected by the perception of the consequences of farmers' behavior and knowledge of pesticide use but negatively influenced by action of governments and trust of retailers. It is important to recognize the differences that exist among different crops growers and locations. Attempt needs to bridge the gap among crop growers, locations and different stakeholder such as government agencies and retailers to develop policy.
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| 7. |
- Alrasheedi, Khlood Ghalib, et al.
(författare)
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GIS-based Spatial Accessibility to Islamic Facilities for Muslim Community in the Melbourne Metropolitan Area
- 2020
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Ingår i: Earth Sciences and Geotechnical Engineering. - UK : Scientific Press International Limited. - 1792-9040. ; 10:5, s. 49-68
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Tidskriftsartikel (refereegranskat)abstract
- The Geographic Information System (GIS) technology has not been widely used in Islamic facilities including mosques, Islamic schools and halal butchers, and is an important issue for the Muslim communities in Melbourne, Australia. This study applied spatial methods to analyze the spatial accessibility to Muslim facilities of the population in Melbourne city. Spatial accessibility is needed because Muslim people believe that they must pray in the mosques, buy halal food and educate their children in Islamic environment. Therefore, this study aimed to (i) identify spatial accessibility by car to the above-mentioned Muslim facilities and (ii) identify disadvantaged Muslim communities and facilities using census data at the fine spatial resolution (i.e. at Mesh Block level). The disadvantaged Muslim commonalities in the Melbourne Metropolitan Area (MMA) were delineated in GIS environment using such techniques as spatial and hot spot analysis, network analysis, mean center and standard distance methods by using ArcGIS 10.3. The spatial accessibility was assessed in terms of travel distance and time, to highlight their differences. This study highlighted the most affected Muslim communities in terms of spatial accessibility, which are located in Hume, Whittlesea, and Melton and Casey suburbs. Furthermore, this study stressed that there is a lack of Mosques and Islamic Schools in the MMA, as approximately 5,000 Muslims do not have proper access to this kind of facilities. The findings of this study could be used by Muslim community when choosing a suburb for their families. Therefore, it is recommended that the urban and regional planners should take the obtained results into consideration to achieve fair and better distribution of Islamic facilities in Melbourne city.
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| 8. |
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| 9. |
- Baby, Sultana Nasrin, et al.
(författare)
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Application of GIS for Mapping Rainwater-Harvesting Potential : Case Study Wollert, Victoria
- 2019
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Ingår i: Engineering. - : Scientific Research Publishing. - 1947-3931 .- 1947-394X. ; 11:1, s. 14-21
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Tidskriftsartikel (refereegranskat)abstract
- Water is a basic normal asset for supporting the condition of life. Accessible water assets are feeling the squeeze because of expanding demand. Soon wa- ter, which we have epended upon to be accessible and an unconditional present of nature will turn into a rare roduct. Protection and conservation of water assets are desperately required. In many parts of Victoria, water supply to communities is limited. Rainwater harvesting systems can provide water ator near the point of demand. The systems can be owner and utility operated and managed. Rainwater collected using existing structures, i.e. rooftops, parking lots, playgrounds, parks, ponds, floodplains etc., has few negative en- vironmental impacts compared to other technologies for water resources de- velopment. Rainwater is relatively clean and the quality is usually acceptablefor many purposes with little or even no treatment. The physical and chemi- cal properties of rainwater are usually superior to sources of groundwater that may have been subjected to contamination. The present study was intended to measure the rooftop rainwater harvesting potential using GIS techniques. The GIS examination utilized in this investigation was basically an efficient assess- ment of rooftop water collecting in the chose Wollert which is a suburb in Melbourne, Victoria. With the use of GIS it was conceivable to appraise the ag- gregate sum of water harvestable at the household level. It is very tedious work to assess the catchments available for rooftop rainwater harvesting. Here the roof surfaces are the catchments and GIS is employed to calculate the area of various types of roofs and their potential for planning for the area under study. As a result Eucalypt Estate Wollert has huge potential and can makeabove 179.11 litres water available per person per day throughout the year.
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| 10. |
- Baby, Sultana Nasrin, et al.
(författare)
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Developing a Spatial Tool for Assessing Coastal Community and Identifying Infrastructure at Risk
- 2021
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Ingår i: Engineering. - China : Scientific Research Publishing Inc. - 1947-3931 .- 1947-394X. ; 13:1, s. 45-55
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Tidskriftsartikel (refereegranskat)abstract
- A recent trend of sea level shows constant rising. Sea level rise has caused asignificant risk to seaside areas. This study examines the potential effect ofclimate change and rising sea levels on coastal regions and evaluates the susceptibilityof coastal areas in Inverloch, Melbourne Australia. A model ofHypothetically Flooded Zones, based on LiDAR data was built, processed andmanipulated in ArcGIS. Through applying this model, the effect of rising sealevel on the infrastructures such as buildings, dwellings, roads, land use andthe population was assessed. Elevation data sets of varying resolution and accuracyhave been processed to show the improved quality of LiDAR datacontributes to a more precise delineation of flood-prone coastal lands. Afterthe susceptible areas to sea level rise were delineated, the worst-case scenariowas calculated (based on the increase in sea level projected for 2100) and itwould impacts about 0.86% of roads, 221 of different building infrastructures.This method can be used in other areas to protect the coasts due to rapidchanges caused by climate change.
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| 11. |
- Baby, Sultana Nasrin, et al.
(författare)
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Developing an Automated City of Whittlesea Urban Tree Canopy Inventory Using Airborne LiDAR and Aerial Imagery
- 2019
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Ingår i: Engineering. - USA : Scientific Research Publishing. - 1947-3931 .- 1947-394X. ; 11:12, s. 828-840
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Tidskriftsartikel (refereegranskat)abstract
- The City of Whittlesea is in Melbourne’s north and is one of the largest municipalities in metropolitan Melbourne. The council GIS team using current aerial photos from 2017 and LiDAR (“LiDAR” stands for Light Detection and Ranging) point clouds 2009 products to identify trends in urban tree canopy cover in the established suburbs of the municipality between 2009 and 2017. The tree canopy coverage was calculated for residential properties, road reservations, public land and park sites within urban parts of Bundoora, Epping, Lalor, Mill Park, Thomastown, and South Morang. From the total project area of approximately 3499 hectares a test site was selected based on an extension of one of the LIDAR data tiles (e325n5828). This project investigates only 6 meters and higher tree canopy cover within the project area. The objectives of the project were to establish a methodology to calculate the urban tree canopy coverage from LiDAR 2009 data, that can be replicated in future calculations. The calculated urban tree canopy coverage from LiDAR 2009 data is 9%, compared to 8% coverage in 2017, based on aerial photography. This estimate was compared to similar Local Governance Areas that range from 12% to 40%. A key to planning and managing urban tree canopy is first to understand the quantity, quality, tree density and distribution of the resource across the landscape. Tree inventories and urban tree canopy analyses comprise an assortment of tools, technologies, and procedures that help us understand the structure and function of our urban tree canopy. The data and information gleaned from urban tree canopy assessments enable resource professionals and policymakers to make informed decisions about ordinances, housing diversity strategy, and budgeting, future tree planting programs and reduce urban heat islands.
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| 12. |
- Baby, Sultana Nasrin, et al.
(författare)
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Finding Areas at Risk from Floods in a Downpour Using the Lidar-Based Elevation Model
- 2021
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Ingår i: Journal of Civil Engineering and Architecture. - USA : David Publishing Company. - 1934-7359 .- 1934-7367. ; 15:1
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Tidskriftsartikel (refereegranskat)abstract
- Climate change can impact coastal areas in different ways, including flooding, storm surges, and beach erosion. Of these, flooding has a major impact on the operation of coastal drainage systems. This paper develops a new flood screening model using a LiDAR based digital elevation model (DEM) to improve the implementation of Victorian’s coastal flooding risk assessment and management. Hydrological elevation models are directed towards protection from cloudbursts and applied to rising sea level. The aim is to simulate water flow on the ground and in streams, and the resulting accumulation of water in depressions of the blue spot using DEM. Due to the presence of pipes, watercourses, bridges and channels it was required that the DEM data to be lowered. The reservoirs of rain will prevent seawater from flowing across the stream channel into land. The rain drain will be open during normal sea levels to allow rain water in the river to move and flow in to the sea. Traditionally, geographic information system (GIS) assists with spatial data management, but lacks modelling capability for complex hydrology problems and cannot be relied upon by decision-makers in this sector. Functionality improvements are therefore required to improve the processing or analytical capabilities of GIS in hydrology. This research shows how the spatial data can be primarily processed by GIS adopting the spatial analysis routines associated with hydrology. The objective of this paper is to outline the importance of GIS technology for coastal flood management. Following a definition of the coastal flood, and, short description of its peculiarities and the urgency of its management, this paper describes the use of GIS technology in coastal flood management, its advantages and the consideration for accuracy. This is followed by the information and LiDAR data required for coastal flood management and the application area in coastal flood management. This paper method is presented to conduct a first high-resolution DEM screening to detect the degree and capacities of the sinks in the coastal landscape. When their capacities are established, the rain volumes received during a rainstorm from their coastal catchments are saved as attributes to the pour points. The conclusion emphases the importance of a geographical information system in coastal flood management for efficient data handling and analysis of geographically related data. Local governments at risk of coastal flooding that use the flood screening model can use to determine appropriate land use controls to manage long-term flood risk to human settlements.
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| 13. |
- Baby, Sultana Nasrin, et al.
(författare)
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Spatial Decision Support System for Coastal Zone Management under a Changing Climate in Victoria, Australia
- 2018
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Ingår i: Engineering. - : Scientific Research Publishing. - 1947-3931 .- 1947-394X. ; 10:10, s. 637-642
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Tidskriftsartikel (refereegranskat)abstract
- The ultimate aim of using spatial datasets and spatial data modelling is fo- cused on enabling a sustainable environment by bringing the public policies into practice. The consequence will be sustainable spatially aware strategic planning for all levels of Australian government. Geographical Information Systems (GIS) are the platform that can serve this aim provided that model, current process and spatial datasets are fit for purpose. To bring public policy into practice a broad range of knowledge from different disciplines is needed. Most decision making processes are pressured in terms of time and driving forces and also the process is beyond the knowledge of individuals in the var- ious disciplines. There is a need for immediate uptake models and tools which are relevant to the target subject that will facilitate this decision making process. This paper focuses on realizing the utility in spatial data and spatial data handling in order to help climate change adaptation programs at local government level. Web-based mapping tools can assist planners prepare for the changing climate conditions in Bass Coast Shire Council. The GIS team has gathered data from various climate research organizations to understand projections of what different climate scenarios might look like over the next 100-year period. From this website demo it is hoped that the user will under- stand how the tool works, background information on different GIS plat- forms, access to interactive mapping, online geospatial analysis tools, videos, open source resource, sea level tools, modelling, 3D visualization and direct download access to various planning and natural resource data sets relating to environment management. Some results from our elevation data analysesthrough these Web map visualization tools are provided.
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| 14. |
- Djurfeldt, Göran, et al.
(författare)
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Afrint database
- 2011
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Annan publikation (övrigt vetenskapligt/konstnärligt)
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| 15. |
- Djurfeldt, Göran, et al.
(författare)
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Using panel survey and remote sensing data to explain yield gaps for maize in sub-Saharan Africa
- 2018
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Ingår i: Journal of Land Use Science. - 1747-423X. ; 13:3, s. 344-357
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this paper is to combine remote sensing data with geo-coded household survey data in order to measure the impact of different socio-economic and biophysical factors on maize yields. We use multilevel linear regression to model village mean maize yield per year as a function of NDVI, commercialization, pluriactivity and distance to market. We draw on seven years of panel data on African smallholders, drawn from three rounds of data collection over a twelve-year period and 56 villages in six countries combined with a time-series analysis of NDVI data from the MODIS sensor. We show that, although there is much noise in yield forecasts as made with our methodology, socio-economic drivers substantially impact on yields, more, it seems, than do biophysical drivers. To reach more powerful explanations researchers need to incorporate socio-economic parameters in their models.
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| 16. |
- Holmquist, Björn, et al.
(författare)
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Approximating Noncentral Chi-Squared to the Moments and Distribution of the Likelihood Ratio Statistic for Multinomial Goodness of Fit
- 2020
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Ingår i: Recent Developments in Multivariate and Random Matrix Analysis : Festschrift in Honour of Dietrich von Rosen - Festschrift in Honour of Dietrich von Rosen. - Cham : Springer International Publishing. - 9783030567736 - 9783030567729
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Bokkapitel (refereegranskat)abstract
- The chi-square distribution is often assumed to hold for the asymptotic distribution of two times the log likelihood ratio statistic under the null hypothesis. Approximations are derived for the mean and variance of G2, the likelihood ratio statistic for testing goodness of fit in a s category multinomial distribution. The first two moments of G2 are used to fit the distribution of G2 to a noncentral chi-square distribution. The fit is generally better than earlier attempts to fit to scaled versions of asymptotic central chi-square distributions. The results enlighten the complex role of the dimension of the multivariate variable in relation to the sample size, for asymptotic likelihood ratio distribution results to hold.
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| 17. |
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| 18. |
- Nasrin Baby, Sultana, et al.
(författare)
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Climate Change Impacts on Water Resources of AryCreek, Inverloch, Victoria
- 2018
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Ingår i: Journal of Civil Engineering and Architecture. - USA : David Publishing Company. - 1934-7359 .- 1934-7367. ; 12:10, s. 727-740
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Tidskriftsartikel (refereegranskat)abstract
- Understanding urban wetland ecosystem services structure allows managers to base restoration efforts on multiple user end-benefits. Ary Creek can provide the coupled function of improving water quality and mitigating floods through delayed stormwater flow. It is fundamental to identify areas surrounded by water for the safety of individual should in case the water level raise beyond areasonable doubt and might cause a flood. For many years, the Ary Creek catchment in Inverloch has been flooding and causing great problems for the inhabitants as well as the environment. The procedure is to develop models of the area around the catchment or watershed using Victorian Coastal LiDAR and other input data from the GIS (geographic information system). This study uses the real-time simulation in ArcSWAT—ArcGIS 10.3 and 3D in ArcScene 10.3, and the variables obtained from the soil and water assessment tool ArcSWAT such as the land use, soil and slope are the parameters measured to induce the flood. When certain portions of the Hydrologic response unit HRU, land use, soil or slope is changed due to temporal adjustment and climate change, then the model can predict zones of low, moderate and high flood risk. The 3D simulations appear to produce a visual model for decision-making, planning, management, and mitigation. The simulation helps in determining the extent of the flood by using animation.
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| 19. |
- Nasrin, Sultana, et al.
(författare)
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Drivers of rice production: evidence from five Sub-Saharan African countries
- 2015
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Ingår i: Agriculture & Food Security. - : Springer Science and Business Media LLC. - 2048-7010. ; 4:12, s. 1-19
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Tidskriftsartikel (refereegranskat)abstract
- Background: In spite of considerable rice production gains over the past 50 years, Sub-Saharan Africa is becoming increasingly dependent on rice imports as demand is outpacing domestic supply. The serious economic and social strains caused by this have urged national leaders to address production deficits. The aim of this article is to analyse and discuss the drivers behind recent changes in rice production in Africa South of the Sahara, focusing on Ghana, Malawi, Nigeria, Tanzania and Mozambique. Considering the period 2002–2008, we model production performance and changes in production amongst 317 rice-growing households using multilevel and longitudinal data. We evaluate and discuss the role of three key processes: the role of commercial drivers, farm technology and macro-level conditions. Results: We show that until 2002, production was driven by a combination of the three key processes considered, while during the period 2002–2008, production increases were primarily associated with area expansion and commercial drivers. This suggests that production lately has been more driven by processes of extensification than intensification. We also note that in none of the periods considered, the share of the state budget allocated to agriculture had a significant effect on production and that recent developments do not give any obvious support for an Asianstyle state-driven Green Revolution in rice in Sub-Saharan Africa. Conclusions: The role of commercialization in explaining changes in production suggests that policies strengthening food staple markets in the sub-continent hold great potential for driving rice production in the near future. Due to the scarcity of available land, the possibilities of further growth in the rice sector are limited without an intensification of production. Hence, farmers also need to access new farm technology, and positive development of rice production would in turn contribute to an improvement of food security.
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| 20. |
- Nasrin, Sultana
(författare)
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Statistical aspects of modeling panel data originating from smallholder household surveys in Sub-Saharan Africa and Vietnam
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis focuses on multivariate multilevel modeling of panel data originated from smallholder farm surveys in Sub-Saharan African (SSA) countries and Vietnam to investigate driving forces in maize and rice production in SSA and diversification of farms in the rice sector in Vietnam. We also present and evaluate different tests for endogeneity in explanatory binary variables in multivariate linear regression models. Paper I discusses drivers behind changes in rice production in SSA. Drivers of production were a combination of area expansion, market integration, farm technology in terms of fertilizer and tractor ploughing, village elite membership and key macro level conditions such as rice imports and GDP per capita. Rice production increase is primarily associated with area expansion and commercial drivers during the period. The role of commercialization changes in production suggests that policies hold great potential for driving rice production in SSA. Paper II focuses on the drivers behind changes in maize production. It is shown that the drivers of production were a combination of area expansion, market integration, farm technology in terms of fertilizer and ploughing, village elite membership and key macro level conditions including share of budget to agriculture and import of maize with some exception within time frame in 2002 and 2008. Maize production increases are primarily associated with area expansion, ploughing, commercial drivers, GDP per capita and village elite membership. Paper III discuss different tests for endogeneity in explanatory binary and counting variables to take into account different aspects of the possible dependence structure between the variable and the disturbance in regression model. The study is shown how approximate equivalent tests can be obtained using the commonly used technique of ‘adding residuals’ to the regression model and which corresponds to tests based on differences of regression parameter estimates obtained under different assumptions. Paper IV investigates the power of some test statistics for testing endogeneity in case of binary endogenous variables. Statistics based on correlations between residuals in the studied regression and the endogenous variable, are studied and compared with the technique of testing significance of the added residual in the studied regression and also the standard Hausman test of endogeneity. Paper V aims to analyse the income diversification patterns of total income of rice farming households in two regions of Vietnam- the Mekong River Delta (MRD) and the Red River Delta (RRD). Two indices; less dominance of rice income, and less dominance of non-farm income of the total household income and their changes over time, defines four categories of farmers: 1) High diversified, 2) Ascenders, 3) Descenders, and 4) Low diversified. In MRD we found that education as resource/wealth, differences in rice production and incomes for households showed a significant effect on total income at the later time frame. Ascenders increased their share of all other incomes but rice, mostly shift to non-farm incomes i.e., out of rice dependence. In the RRD region only initial higher income level effected in income in 2005. The ascenders increased their incomes substantially while the descenders, more dependent on rice income, sharp fall in income. Higher education level and smaller farm sizes reduce the importance of education and rice productivity changes in RRD.
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