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The urgency to preserve tropical forest remnants has encouraged the development of remote sensing tools and techniques to monitor diverse forest attributes for management and conservation. State-of-the-art methodologies for mapping and tracking these attributes usually achieve accuracies greater than 0.8 for forest cover monitoring; r-square values of ~0.5–0.7 for plant diversity, vegetation structure, and plant functional trait mapping, and overall accuracies of ~0.8 for categorical maps of forest attributes. Nonetheless, existing operational tropical forest monitoring systems only track single attributes at national to global scales. For the design and implementation of effective and integrated tropical forest monitoring systems, we recommend the integration of multiple data sources and techniques for monitoring structural, functional, and compositional attributes. We also recommend its decentralized implementation for adjusting methods to local climatic and ecological characteristics and for proper end-user engagement. The operationalization of the system should be based on all open-source computing platforms, leveraging international support in research and development and ensuring direct and constant user engagement. We recommend continuing the efforts to address these multiple challenges for effective monitoring.

The area affected by sinkholes in Thulibeshi Phat of Armala VDC, Pokhara was studied in order to understand natural settings of the study area. A total of 117 sinkholes from depth range of 1 to 5 m and diameters from 1 to 15.2 m were observed at the time of our field visit. Out of these sinkholes, 52 sinkholes were filled sinkholes, 12 were water-bearing sinkholes and others were opened sinkholes. The area consists of sediments of fluvio-lacustrine and debris deposits and the sinkhole site has sediments mainly of silt, clay and fine sand size with chemical compositions of kaolin of major silica and minor constituents of calcium carbonate. The main mechanism of formation of sinkholes in Thulibeshi Phat was washed-away effect generated by piping mechanism of fine sediments by sub-surface flowing water, which was initiated by partial dissolution of carbonate containing sediments. Human impact on landscape, especially land use changes and stream channel modifications accelerated the process of piping mechanism for initiating and extending the sinkhole affected area in the present study site. This study will help to understand how geological conditions and human impacts interact to form sinkhole hazards in Nepal.

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