Seasonality of first admissions for schizophrenia in the southern hemisphere

Abstract

This case study was done to determine the impact of seasonal climate variability on rice production in the Nam Dong District, Central Highland of Vietnam. The Ordinary Least Square method was applied to establish the relationships between climatic factors and rice yields in two different growing seasons. The climatic factors are average maximum temperature (avemaxT), average minimum temperature (aveminT) and average rainfall (averain). The rice growing seasons are known as the Winter-Spring (WS) and Summer-Autumn (SA) season. The data of climate factors and rice yield during these two growing seasons were collected from District Meteorological Station and District Statistical Office over 27 years. The data used was from the years 1986 to 2012. A focus group discussion also was held with local rice farmers. The information gathered during this discussion was processed by using the timeline trend, which is a Participatory Rural Approach (PRA) tool. The farmers were invited to share their thoughts, experiences and opinions related to the impact of climate variability on their individual rice production. Moreover, an in-depth interview was conducted with local extension and agricultural officers to discuss the past losses of rice production caused by climate variability that occurred in Nam Dong district.The results from Ordinary Least Square show that seasonal averain, avemaxT, and aveminT had significant effect on rice yield. While, it was found that the seasonal averain factor had a positive relationship with rice yield and that the seasonal avemaxT affected adversely on rice yield of the two growing seasons. In addition, rice yield in the SA season did not relate to seasonal aveminT. This climate variable had positive impact on WS rice yield at statistical significant level. Moreover, participants in the focus group discussion reported that many climate events were irregular and unpredictable. An example of this is that droughts occurred more frequently, which caused negative impact on rice production. The result of in-depth interview also confirmed that drought, storm, pest and disease were the main cause losses of rice production under climate variability.The research results provide valuable information to assist local governments in rural socioeconomic development plans to minimize the impacts of adverse climate conditions. Moreover, Meteorological Stations, agricultural and extension units will also benefit from this data to help improve their communication methods when disseminating to the farmers current or accurate climate conditions, climate predictions and climate patterns.