Spatial Relation of Bumblebees (Hymenoptera-Apidae) with Host-Plant and their Conservation Issues: An Outlook from Urban Ecosystem of Kathmandu Valley, Nepal

Ecology and conservation status of bumblebee species remains poorly understood, especially in rapidly degrading urban ecosystems, which is important considering the role of bumblebees in the pollinations. We collected more than 200 bumblebee (Bombus spp.) specimens under six species in different parts of the Kathmandu valley (Kathmandu, Lalitpur, and Bhaktapur cities) in Nepal. The species of bumblebees were analyzed with their host plant types and the land use change using remote sensing and field observation data. We found that the bumblebees exert strong variation and were significantly affected by the families of the host plants and the nature of flowers (open and closed type) rather than colors and categories (invasive and noninvasive). We underline that the rapid habitat loss by changing land use in the study area can be a potential threat to the conservation of these important pollinators, and thus, need focused habitat conservation efforts

Factors controlling the accelerated expansion of Imja Lake, Mount Everest region, Nepal

This study explores the link between area increase of Imja Tsho (Lake) and changes of Imja Glacier (area ∼25km2) under the influence of climate change using multitemporal satellite imagery and local climate data. Between 1962 and 2013, Imja Lake expanded from 0.03±0.01 to 1.35±0.05 km2 at a rate of 0.026±0.001 km2 a-1. The mean glacier-wide flow velocity was 37±30ma-1 during 1992-93 and 23±15ma-1 during 2013-14, indicating a decreasing velocity. A mean elevation change of -1.29±0.71ma-1 was observed over the lower part of the glacier in the period 2001-14, with a rate of -1.06±0.63ma-1 in 2001-08 and -1.56±0.80ma-1 in 2008-14. We conclude that the decrease in flow velocity is mainly associated with reduced accumulation due to a decrease in precipitation during the last few decades. Furthermore, glacier ablation has increased due to increasing maximum temperatures during the post-monsoon months. Decreased glacier flow velocities and increased mass losses induce the formation and subsequent expansion of glacial lakes under favourable topographic conditions.Publisher PDFPeer reviewe

Improving decision support system in identifying vulnerability rating and prioritizing the best interventions for sustainable watersheds in Pakistan, Nepal, and Sri Lanka

Quantification of watershed vulnerability rating and prioritization of the best watershed management intervention is always a challenge for multidisciplinary experts in developing consensus. Consequently, the lack of a decision support system (DSS) negatively affects the adoption of promising interventions leading to reduced watershed communities’ resilience to climate change. Therefore, a DSS has been developed to integrate local multi-disciplinary knowledge in identifying the watershed vulnerability ratings and prioritizing the best site-specific watershed management interventions. The DSS developed was applied to selected watersheds using 25 local experts each in Pakistan, Nepal, and Sri Lanka. The results showed the DSS is conveniently applicable and effective in developing consensus among multidisciplinary experts. The DSS recommended that the best interventions for the selected watersheds should primarily reduce the existing accelerated land and water degradation through engineering and biological actions, namely the control the rainwater run-off losses through appropriate harvesting systems and their subsequent efficient utilization for improving food security, climate change resilience and livelihood of vulnerable watershed communities. The DSS developed can be helpful in developing local adaptation plans and strengthening the policy support for promoting sustainable watersheds in Pakistan, Nepal, and Sri Lanka. However, the system needs further refinement through the incorporation of the design, specifications and costing of the interventions and making the data acquisition and analysis automatic using an online electronic system for quicker results and appropriate resource allocation for stimulated adoption.Quantification of watershed vulnerability rating and prioritization of the best watershed management intervention is always a challenge for multidisciplinary experts in developing consensus. Consequently, the lack of a decision support system (DSS) negatively affects the adoption of promising interventions leading to reduced watershed communities’ resilience to climate change. Therefore, a DSS has been developed to integrate local multi-disciplinary knowledge in identifying the watershed vulnerability ratings and prioritizing the best site-specific watershed management interventions. The DSS developed was applied to selected watersheds using 25 local experts in Pakistan, Nepal, and Sri Lanka. Results showed that DSS is conveniently applicable and effective in developing consensus among multidisciplinary experts. The DSS recommended that the best interventions for the selected watersheds should primarily reduce the existing accelerated land and water degradation through engineering and biological actions. These actions may include controlling the rainwater run-off losses through appropriate harvesting systems and their subsequent efficient utilization for improving food security, climate change resilience and livelihood of vulnerable watershed communities. The DSS developed can be helpful in developing local adaptation plans and strengthening the policy support for promoting sustainable watersheds in Pakistan, Nepal, and Sri Lanka. However, the system needs further refinement through the incorporation of the design, specifications and costing of the interventions and making the data acquisition and analysis automatic using an online electronic system for quicker results and appropriate resource allocation for stimulated adoption

Experience With a Hard and Soft Participatory Modeling Framework for Social-ecological System Management in Mount Everest (Nepal) and K2 (Pakistan) Protected Areas

High mountains have sensitive social-ecological systems (SESs) characterized by fragility, complexity, and marginality. The local economies of these environments mainly rely on primary production, tourism, and leisure activities; thus human-ecosystem interactions are intricately linked. Many authors stress that this strict relationship must be assisted with a participatory approach involving interested stakeholders in the conceptualization, specification, and synthesis of knowledge and experience into useable information for the express purpose of addressing a problem complex. This paper presents experience garnered with a participatory modeling framework combining hard and soft methodology in 2 case studies: the Sagarmatha National Park and Buffer Zone (Nepal) and the Central Karakoram National Park (Pakistan). The modeling framework was developed based on local stakeholders' demands and needs; it consists of 5 modules, briefly presented here along with their conceptual background. In developing the framework, particular emphasis was given to considering the needs of decision-makers at the local level, rather than simply providing technical solutions to abstract problems. From the development of this modeling process, a need emerged to structure a management-oriented research module in order to generate management knowledge that is both stakeholder-relevant and evidence-based. The application of the framework in the 2 cases studies showed that the modeling can trigger valuable discussion among stakeholders as well as guidance for management-oriented research and feedback loops ensuring validation of knowledge. In addition, the resulting scenarios can help decision-makers in defining pathways for sustainable development in mountain areas, where people's livelihoods are closely dependent on ecosystems. The framework was developed in such a way that it can be replicated in other mountain areas with similar challenges

Open-Source Data Alternatives and Models for Flood Risk Management in Nepal

Availability and applications of open-source data for disaster risk reductions are increasing. Flood hazards are a constant threat to local communities and infrastructures (e.g., built-up environment and agricultural areas) in Nepal. Due to its negative consequences on societies and economic aspects, it is critical to monitor and map those risks. This study presents the open access earth observation (EO) data, geospatial products, and different analytical models available for flood risk assessment (FRA) and monitoring in Nepal. The status of flood risk knowledge and open-source data was reviewed through a systematic literature review. Multispectral optical data are widely used, but use of microwave data is extremely low. With the recent developments in this field, especially optical and microwave data, the monitoring, mapping, and modeling of flood hazards and risk have been more rapid and precise and are published in several scientific articles. This study shows that the choice of appropriate measurements and data for a flood risk assessment and management involves an understanding of the flood risk mechanism, flood plain dynamics, and primary parameter that should be addressed in order to minimize the risk. At the catchments, floodplains, and basin level, a variety of open data sources and models may be used under different socioeconomic and environmental limitations. If combined and analyzed further, multi-source data from different models and platforms could produce a new result to better understand the risks and mitigation measures related to various disasters. The finding of this study helps to select and apply appropriate data and models for flood risk assessment and management in the countries like Nepal where the proprietary data and models are not easily accessible

Assessment of channel migration of Koshi River in Nepal using remote sensing and GIS

River channel shifting involves the lateral migration of an alluvial river channel across its floodplain. High planform dynamics are a distinctive feature of the Koshi river, particularly in the lower stretches as a result of recurring floods. In this research, the dynamics of channel planform and shifting through systematic analysis and interpretation of diverse channel configurations using multidate Landsat TM 5 images (1999 and 2009) and Sentinel-2A image (2019) of the Koshi River from Chatara to the Nepal-India border has been studied. Remote sensing techniques and GIS environment was used for change analysis based on the satellite imageries. The channel shifting was determined by assessing and estimating the transient changes in the planform from the temporal satellite data. The results indicated that the Koshi River is highly braided over the stretch of 48 km south from Chatara. It can be easily visualized that the southern section of the river has more river stretch and braiding than the northern section. Between 1999 and 2019, the area of the water channel is reduced by 24.08 km2 whereas, the channel bars have increased by 68.08 km2. The river was observed having experienced a clear shift of the channel toward the west in recent years. The average annual rate of shifting was estimated to be 21.6 m year−1 towards the west and 0.8 m year−1 towards the east, with the overall expansion of the river flood plains. This study can be utilized for developing integrated sustainable river and land management plans in the Koshi basin and support future researches on relevant topics