Journal of Forest and Natural Resource Management

Wetland Mapping and Monitoring with Sentinel-1 and Sentinel-2 Data on the Google Earth Engine

Roshan Kumar Chaudhary — 2023-11-24

Wetlands are one of the most valuable ecosystems on the Earth for both humans and nature. Large-scale of wetlands have been transformed into agriculture and urban region in response to human demands and requirements. Accurate mapping and monitoring of large-scale wetlands are of high importance but also challenging. The growing availability of large volumes of open-access satellite data and development of advanced machine-learning algorithms has been providing new opportunities for mapping and monitoring earth system and environment. Google Earth Engine (GEE)- a cloud-based computing platform, has been effectively applied in various areas of mapping ranging from forestry, agriculture, hydrological studies. This study uses high spatial resolution satellite data from Sentinel-1, Sentinel-2 and terrain indices for mapping and monitoring of wetlands of Pokhara Metropolitan city of central Nepal. We implemented different types of wetland classification models on the GEE platform using the Random Forest (RF) classifier. The model with lowest out-of-bag error was chosen as the final model for the preparation of the final classified wetland map. The overall accuracy and kappa coefficient of the classified map were 98% and 0.97 respectively. The study demonstrated the possibility of rapid monitoring of wetlands and other land characteristics using the Google Earth Engine platform.

Who decides and how? Understanding the initiation and implementation dynamics of scientific forestry in community forests in the mid hills of Nepal

Sunil Subedi — 2023-11-24

Scientific forest management (SciFM) was in the initial phase of its implementation and practice in Nepal. However, it is discontinued due to the conflicting opinions among the forestry stakeholders. This study investigated the SciFM plan preparation process, and the involvement of different stakeholders in the planning, implementation, and capacity enhancement of community forest user groups (CFUGs) in two community forests of the Kaski District, Nepal. For this, we used a household survey (n = 101), key-informant interview (n = 15), and focus group discussion (n = 3). The study found that forest technicians were dominant over users during the SciFM plan preparation process as well as in decision-making. While in the case of implementation, it was CFUGs, who play a leading role to accomplish most of the activities. During the plan implementation, the higher percentage of involvement of users was in thinning, pruning and weeding activity (50%), followed by social development (20%) and timber-related activities (20%). However, the majority of the respondent considered that SciFM was highly technical and 90% of the respondents could not implement the plan. The forest authority (DFO), the executive committee, and the Federation of Community Forestry Users Nepal (FECOFUN) were involved in the capacity building of the users to some extent during the planning and implementation of SciFM. The results of this study could be the baseline information for the successful planning and implementation of silviculture-based forest management in other parts of the country

Ecological Significance and Conservation Issues of Internationally Important Wetlandsof Nepal: A Review

Roshan Singh Thagunna — 2023-11-24

Wetlands, once considered unproductive land, are now recognized as highly productive ecosystems with significant biodiversity. Nepal has 10 wetlands listed on the Ramsar Sites but their degradation is becoming a growing concern. Therefore, this review paper investigates the ecological significance and conservation issues of internationally important wetlands in Nepal using an analytical framework called DPSIR (Driving Force-Pressure-State-Impact-Response). The study discovered that wetlands offer various advantages, encompassing ecological, economic, aesthetic, religious, and socio-cultural benefits. Nevertheless, they face obstacles such as encroachment, pollution, sedimentation, the invasion of non-native species, and the decline of biodiversity, which endanger their ecological attributes. Despite having a national wetland policy and strategic plan, their implementation is insufficient. The current status of wetlands in Nepal is declining, indicating the urgent need for a review and strong implementation of existing policies, programs, and institutional arrangements.

Analyzing the Relationship Between Above Ground Biomass and Different Vegetation Indices of Chure Region of Sainamaina Municipality, Nepal

Ananta Poudel — 2023-11-24

For REDD+ (reducing emissions from deforestation and forest degradation), sustainable management of forests, and protection and enhancement of forest carbon stocks procedures to be successful, accurate measurement of forest above-ground biomass (AGB) are essential. Sentinel imaging that was launched since 2014 provides an opportunity for mapping and monitoring AGB in forests. The aim of this study is to analyze the relationship between AGB and vegetation indices (VIs) derived from Sentinel-2 imagery in the Chure region of Sainamaina municipality. For this, we used 72 sample plots and 7 different VIs. The ARVI(Atmospherically Resistant Vegetation Index) and EVI2 (Enhanced Vegetation Index - 2) shows strong correlation (i.e. r = 0.861 and 0.861) and coefficient of determination value (R2=0.7414 and 0.7415) respectively. Overall, Sentinel-2 multispectral images vegetation indices can produce good results for reporting the AGB.

Soil Erosion Analysis Using GIS and RS in Makawanpur District, Nepal

Subash Budhathoki — 2023-11-24

Although soil erosion is a common phenomenon and a serious hazard in many areas of the Makawanpur district, it is still challenging to estimate and assess the amount of soil erosion. This study investigates the distribution of soil erosion in the Makawanpur district using the Revised Universal Soil Loss Equation (RUSLE) and Geographic Information System (GIS). RUSLE model parameters were collected from various sources. Topography, rainfall, soil characteristics, and soil conservation techniques were considered in the study, among many other erosion factors. These variables were multiplied to determine the average soil loss. Based on the severity of the erosion, the final results of soil erosion rates were divided into six classes. Very serious class accounts for 11.31% of the land (>80 t h-1 yr-1), followed by severe which is 9.76% of the land with erosion rate rates ranging from (40-80 t h-1 yr-1), very high is 17.41% of the land with rates ranging from (20-40 t h-1 yr-1), followed by 16.38% of the land ranging from(10-20 t h-1 yr-1), and 9.32% of the land ranging from (5-10 t h-1 yr-1) and 35.83% of the land ranging from (0-5 t h-1 yr-1), fall under, moderate, low and very low severity zones respectively. The GIS-based soil erosion model is found to be a cost-effective method to estimate soil erosion as well as to identify priority areas for sustainable land management practices.

Editorial Remarks

Editorial Board — 2023-11-24

Not available