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    Use of new generation geospatial data and technology for low cost drought monitoring and SDG reporting solution : a thesis presented in partial fulfillment of the requirement for the degree of Master of Science in Computer Science at Massey University, Manawatū, New Zealand
    (Massey University, 2018) Dehghan-Shoar, Mohammad Hossain
    Food security is dependent on ecosystems including forests, lakes and wetlands, which in turn depend on water availability and quality. The importance of water availability and monitoring drought has been highlighted in the Sustainable Development Goals (SDGs) within the 2030 agenda under indicator 15.3. In this context the UN member countries, which agreed to the SDGs, have an obligation to report their information to the UN. The objective of this research is to develop a methodology to monitor drought and help countries to report their ndings to UN in a cost-e ective manner. The Standard Precipitation Index (SPI) is a drought indicator which requires longterm precipitation data collected from weather stations as per World Meteorological Organization recommendation. However, weather stations cannot monitor large areas and many developing countries currently struggling with drought do not have access to a large number of weather-stations due to lack of funds and expertise. Therefore, alternative methodologies should be adopted to monitor SPI. In this research SPI values were calculated from available weather stations in Iran and New Zealand. By using Google Earth Engine (GEE), Sentinel-1 and Sentinel- 2 imagery and other complementary data to estimate SPI values. Two genetic algorithms were created, one which constructed additional features using indices calculated from Sentinel-2 imagery and the other data which was used for feature selection of the Sentinel-2 indices including the constructed features. Followed by the feature selection process two datasets were created which contained the Sentinel- 1 and Sentinel-2 data and other complementary information such as seasonal data and Shuttle Radar Topography Mission (SRTM) derived information. The Automated Machine Learning tool known as TPOT was used to create optimized machine learning pipelines using genetic programming. The resulting models yielded an average of 90 percent accuracy in 10-fold cross validation for the Sentinel- 1 dataset and an average of approximately 70 percent for the Sentinel-2 dataset. The nal model achieved a test accuracy of 80 percent in classifying short-term SPI (SPI- 1 and SPI-3) and an accuracy of 65 percent of SPI-6 by using the Sentinel-1 test dataset. However, the results generated by using Sentinel-2 dataset was lower than Sentinel-1 (45 percent for SPI-1 and 65 percent for SPI-6) with the exception of SPI-3 which had an accuracy of 85 percent. The research shows that it is possible to monitor short-term SPI adequately using cost free satellite imagery in particular Sentinel-1 imagery and machine learning. In addition, this methodology reduces the workload on statistical o ces of countries in reporting information to the SDG framework for SDG indicator 15.3. It emerged that Sentinel-1 imagery alone cannot be used to monitor SPI and therefore complementary data are required for the monitoring process. In addition the use of Sentinel-2 imagery did not result in accurate results for SPI-1 and SPI-6 but adequate results for SPI-3. Further research is required to investigate how the use of Sentinel-2 imagery with Sentinel-1 imagery impact the accuracy of the models.
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    Impact assessment of the 1990 East Coast technology transfer programme : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Agricultural Science in Farm Management, Massey University
    (Massey University, 1995) Walker, Philip B
    The East Coast of the North Island experienced serious drought conditions during the summer of 1988/89, which severely depressed farm production and profitability. To assist farmers recover from the drought the Government provided $30 million in the form of a special "Drought Recovery Assistance Programme". Part of the budget was assigned to a Technology Transfer Programme (incorporating an Alternative Pasture Demonstration Programme). This programme aimed to mitigate future drought risk, promote dryland farming sustainability and reduce the need for future Government intervention by encouraging farmers to adopt a range of short- and long-term practices in their overall farming system. A farm 'systems' approach to technology transfer differentiated this programme from previous adverse event assistance. The Government, farmers and the agencies responsible for the East Coast Technology Transfer Programme were interested in whether this new approach to technology transfer had been successful. The objectives of this research were to assess the programme's success relative to its objectives and in terms of its on-farm impact. Telephone, mail and interview surveys of farmers located in the East Coast region were conducted. Data about processes used for the dissemination of information, the type and amount of technology adopted, and the attitude of farmers to future droughts and Government intervention were collected. Most of the farmers (91%) contacted in the telephone survey (n=200 farmers) had changed some aspect of their farming system in order to decrease its susceptibility to drought, and 81% now consider themselves to be better equipped to successfully manage drought conditions. Written material prepared for the programme was most often cited by farmers as an information source. The most common changes made by farmers were the incorporation of new pasture (52%), more timely decision making (48%), increased proportions of readily disposable livestock and greater use of feed supplements to counteract the effects of a drought. Half (50%) of the farmers surveyed believed that no Government assistance should be provided if a drought was to occur again. The mail survey to evaluate farmers (n=69) involved in the Alternative Pasture Species Demonstration Programme indicated that the area sown in alternative pasture species had increased from an average of 16 hectares in 1991/92 to 37 hectares in June 1994. Most farmers believed that the alternative pasture species were superior to their existing traditional ryegrass/white clover pastures. However, out of a list of six drought management options encouraged through the Technology Transfer Programme, farmers rated alternative pasture species as second to least important in reducing the effect of a drought on their farm, although they still considered this option as either "important" (49%) or "very important" (44%). Most farmers (74%) said that "early decisions on livestock numbers for summer" was "very important". Adoption of alternative pasture species by farmers who had made direct contact with alternative pasture demonstration farmers was low. Personal interviews with farmers (n=10) neighbouring Focus Farms (n=2) and a mail survey of the consultants (n=14) responsible for their selection and field day programme indicated that Focus Farms did not attract large numbers of farmers, although those that attended were generally positive about the information provided through this medium. Some of the recommended technologies and management practices were not appropriate for some farmers. Technologies that were encouraged through the field days, and which have been adopted, were a greater proportion of trading stock, the use of alternative pasture species, reduction of overall stocking rate, incorporation of summer-moist run-offs, and more reserved supplementary feed. Most farmers had made at least one 'drought proofing' change to their farming system since 1989 and now felt more confident to cope with drought conditions. However it was not possible to determine how much change occurred due to the influence of the Technology Transfer Programme relative to the farmer's own drought experience, the wider base of agricultural knowledge available to farmers, the influence of other farming and non-farming objectives and improved financial returns for farm products since 1990. The present Government policy of non-intervention is now accepted by the majority of farmers. Future adverse event relief programmes are therefore not expected by farmers, although some would like flexibility with items such as taxation when farm profit is radically altered because of drought management.