Impact of Plantation Induced Forest Degradation on the Outbreak of Emerging Infectious Diseases-Wayanad District, Kerala, India.

The world has been facing a pandemic owing to COVID-19. We have also seen the geographic expansion and outbreaks of other emerging infectious diseases (EID) in recent years. This paper investigates the direct and indirect effects of land use land cover change (LULCC) on EID outbreaks in the context of Wayanad District of Kerala, India. Wayanad is in the vulnerable tropical forested region, and it is named as one of the four environmental change hotspots. The focus of this project is mainly three EIDs prevalent in this region: Kyasanur forest disease (KFD), Dengue and Leptospirosis. Our results, based on topographical map, remote sensing and extensive field work, show that the natural forest in Wayanad was replaced with agriculture and forest plantation during 1950-2018. This paper further suggests that encroachment of forest by forest plantation causes the human-animal conflict resulting in the outbreak of KFD cases. Our analysis reveals that a high number of Dengue cases is found in the forested regions of the district and over the adjacent human-made agriculture plantation areas. High and medium number of Leptospirosis cases contain a high portion of land area devoted to paddy cultivation and agricultural plantation. In summary, the results clearly show the linkage between the outbreak of above mentioned EIDs and LULCC in the context of Wayanad district, Kerala. We also discuss in detail the causal pathway involving human-environmental dynamics through which plantation leads to the outbreak of KFD. Replacing forests with plantations poses an alarming threat of disease outbreak in the community.

The role of local heating in the 2015 Indian Heat Wave.

India faced a major heat wave during the summer of 2015. Temperature anomalies peaked in the dry period before the onset of the summer monsoon, suggesting that local land-atmosphere feedbacks involving desiccated soils and vegetation might have played a role in driving the heat extreme. Upon examination of in situ data, reanalysis, satellite observations, and land surface models, we find that the heat wave included two distinct peaks: one in late May, and a second in early June. During the first peak we find that clear skies led to a positive net radiation anomaly at the surface, but there is no significant sensible heat flux anomaly within the core of the heat wave affected region. By the time of the second peak, however, soil moisture had dropped to anomalously low levels in the core heat wave region, net surface radiation was anomalously high, and a significant positive sensible heat flux anomaly developed. This led to a substantial local forcing on air temperature that contributed to the intensity of the event. The analysis indicates that the highly agricultural landscape of North and Central India can reinforce heat extremes under dry conditions.