Studies on the assessment of land degradation, overland flow, soil loss, and nutrient loss have emerged as paramount importance for food security and rural livelihood in the mountains. The present study dealt with similar issues in the Eastern Himalayas, for which the primary data were collected from the field during 2017–18. Quantitative and qualitative methods were used to collect data on soil erosion and information on overland flow, soil loss, and nutrient loss was assessed through field experiments in the watershed of Sikkim, Eastern Himalayas. The first section of the methodology deals with the experimental analysis from different land use categories to quantify soil loss. In the second section, detailed qualitative analyses of farmers’ perceptions of soil erosion indicators were recorded through field surveys, i.e., key informant interviews (KEIs) and focus group discussions (FDGs). The results showed that the highest overland flow was in barren land (8.63%) followed by large cardamom-based agroforestry system (7.02%), and mixed cropping (4.84%), and the lowest overland flow was in terrace cultivation (4.69%). Soil loss was estimated to be the highest for barren land (7.73 Mg/ha/year (megagram/hectare/year)) followed by mixed cropping (4.32 Mg/ha/year), and terrace cultivation (3.75 Mg/ha/year), with the least soil loss estimated to be in cardamom-based agroforestry (3.23 Mg/ha/year). Loss of nitrogen (N) (4.49 kg/ha/year) and phosphorous (P) (2.43 kg/ha/year) were highest in barren land, while potassium (K) loss was highest (4.30 kg/ha/year) in mixed farming. The lowest N loss rate (3.34 kg/ha/year) was in terrace cultivation, the lowest P loss rate (8.19 kg/ha/year) was in mixed farming, and the lowest potassium loss rate (3.28 kg/ha/year) was in cardamom-based agroforestry. Approximately 33% of the farmers acknowledged light or no soil losses, while 17% of the farmers accepted moderate soil erosion. The results of field survey indicated that only 15–19% of the farmers reported high or extreme soil loss in the fields. Farmers in the watershed are practicing multiple measures to control land degradation; however, marginal farmers are still vulnerable and need strong support from the government to safeguard their land.
Agriculture is the major source of livelihood in rural areas and is considered the backbone of the Indian economy. In Sikkim, agriculture is being practiced by 80% of the rural population, and having no other major livelihood options has created immense pressure on the farmers and agricultural land. Agriculture sector is under great stress as the farmers are being confronted by various challenges in Sikkim Himalaya in recent years, such as land degradation, climate change and socio-economic problems. Despite the number of indigenous agriculture management methods being practised in Sikkim Himalaya, the agricultural production system is weakening. In this context, this paper presents an analysis of challenges faced by indigenous communities, local farmers and potential sustainable strategies for their management in Rani Khola watershed of Sikkim Himalaya. Data and information were collected by field observation, questionnaire surveys of 300 households, key informant interviews and focus group discussions conducted during 2017–18. Data processing and analysis were carried out with a combination of techniques, such as the application of remote sensing (RS), geographic information system (GIS)-based data processing and descriptive statistics. Major challenges identified in the watershed are water scarcity (80%), climate change (88%), soil erosion and runoff (72%), higher investment cost (100%), lack of irrigation facilities (77%), fragmentation and size of landholdings (100), human–wildlife conflict (59%) and pests and disease (60%). Some possibilities and innovations that could address these problems are the use and retaining of various indigenous soil and water conservation (SWC) measures, diversified farming systems, community involvement in the government development process, better irrigation facilities, strengthening the local economy, coordinated planning between stakeholders and development of market feedback mechanism within the system.
The direct current (dc) conductivity (σdc) of pristine and ferric chloride doped poly(3-octylthiophene) has been measured in the temperature range of 6–300K. Mott’s three-dimensional variable range hopping and thermally activated tunneling are suggested as the dominant mechanisms of dc conduction at high (77–300K) and low (<77K) temperature regions, respectively.