Summary This paper reports the range and statistical distribution of oxidation rates of atmospheric CH4 in soils found in Northern Europe in an international study, and compares them with published data for various other ecosystems. It reassesses the size, and the uncertainty in, the global terrestrial CH4 sink, and examines the effect of land‐use change and other factors on the oxidation rate. Only soils with a very high water table were sources of CH4; all others were sinks. Oxidation rates varied from 1 to nearly 200 μg CH4 m−2 h−1; annual rates for sites measured for ≥1 y were 0.1–9.1 kg CH4 ha−1 y−1, with a log‐normal distribution (log‐mean ≈ 1.6 kg CH4 ha−1 y−1). Conversion of natural soils to agriculture reduced oxidation rates by two‐thirds –‐ closely similar to results reported for other regions. N inputs also decreased oxidation rates. Full recovery of rates after these disturbances takes > 100 y. Soil bulk density, water content and gas diffusivity had major impacts on oxidation rates. Trends were similar to those derived from other published work. Increasing acidity reduced oxidation, partially but not wholly explained by poor diffusion through litter layers which did not themselves contribute to the oxidation. The effect of temperature was small, attributed to substrate limitation and low atmospheric concentration. Analysis of all available data for CH4 oxidation rates in situ showed similar log‐normal distributions to those obtained for our results, with generally little difference between different natural ecosystems, or between short‐and longer‐term studies. The overall global terrestrial sink was estimated at 29 Tg CH4 y−1, close to the current IPCC assessment, but with a much wider uncertainty range (7 to > 100 Tg CH4 y−1). Little or no information is available for many major ecosystems; these should receive high priority in future research.

This study explores different socio-economic and institutional factors influencing the adoption of improved soil conservation technology (ISCT) on Bari land (Rainfed outward sloping terraces) in the Middle Mountain region of Central Nepal. Structured questionnaire survey and focus group discussion methods were applied to collect the necessary information from farm households. The logistic regression model predicted seven factors influencing the adoption of improved soil conservation technology in the study area including years of schooling of the household head, caste of the respondent, land holding size of the Bari land, cash crop vegetable farming, family member occupation in off farm sector, membership of the Conservation and Development Groups, and use of credit. The study showed that technology dissemination through multi-sectoral type community based local groups is a good option to enhance the adoption of improved soil conservation technology in the Middle Mountain farming systems in Nepal. Planners and policy makers should formulate appropriate policies and programs considering the farmers' interest, capacity, and limitation in promoting improved soil conservation technology for greater acceptance and adoption by the farmers.

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Soil aggregation is an important process of C sequestration and hence a useful strategy to mitigate the increase in concentration of atmospheric CO2 We studied water stability of soil aggregates (WSA) and soil organic carbon (SOC) associated with aggregates and primary particles in surface (0–10 cm) and subsurface (10–20 cm) layers of cultivated (khet, irrigated lowland, and bari, rainfed upland) and forest lands (dense Shorea forest, degraded forest and shrub land, pine–Shorea forest, Shorea–pine–Schima forest, and Schima–Castanopsis forest) in a mountain watershed of Nepal. Macroaggregates (>2 mm) were abundant in forest soils (41–70%) while microaggregates (<0.5 mm) were abundant (56–63%) in cultivated lands. Pine mixed forest contained more macroaggregates in both layers. Mean WSA in the surface soil was highest in Shorea–pine–Schima forest (96%) and lowest in khet (74%). Macroaggregates in the surface layers contained 14.9 to 24.8 and 5.5 to 20.7 g kg−1 SOC in cultivated and forest soils, respectively, while microaggregates contained 12.5 to 30.8 and 11.9 to 25.4 g kg−1 SOC, respectively. The forest soils contained more sand (639–834 g kg−1) and fewer clay particles (49–95 g kg−1) than the cultivated soils. Soils under natural forest, however, were characterized by higher SOC associated with all primary particles. Cultivated soils contained higher amounts of clay but less clay‐associated SOC than forest soils. The relation between clay content and clay‐associated SOC was explained by a quadratic function (R2 = 0.45, P = 0.002).

The effects of climate change have negatively affected Malawi's agricultural production. In this context, fisheries have been providing alternative livelihoods. However, there is a knowledge gap around the responses of small-scale fishers to climate-related changes. Therefore, a study was conducted on the Western shores of Lake Malawi between August 2015 and April 2016. The study evaluated the perceived effects of climate change on small-scale fishers and their coping strategies by employing a wide range of methods for data collection and analysis. The study used explorative surveys, household surveys, focus group discussions and key informant interviews to collect data. The study randomly sampled 112 household heads who owned either fishing gear or a fishing vessel or both. Content analysis for themes was used to analyse the qualitative data. The Mann-Kendal Test was used to analyse trends in meteorological data, and binary logistic regression was used to determine factors that influence coping with low fish catches. Despite the respondents noticing an increased incidence of extreme weather events and low fish catches, their perceptions could not be validated using time series meteorological data. However, such perceptions were influenced by experience from long-time exposure to extreme weather events and to low fish catches. The majority of the fishers had adjusted to these changes by increasing their fishing time, using highly efficient illegal fishing nets, expanding farming land, operating small businesses and undertaking casual labour in agriculture and fishing activities. The fishers' propensity to adjust to these changes increased due to the presence of the following factors: older age of household head, higher education level, being married and having an annual income. In contrast, being a member of fish conservation club decreased the probability of adjusting. This study emphasizes the need to be cautious when defining and framing perceptions of local communities on extreme weather events as data obtained could be misleading. Furthermore, a multi-sectoral approach to balance sustainable livelihoods and management of fisheries is needed. These findings provide theoretical and practical lessons that can inform design, planning and implementation of policies that enhance adaptive capacity in fisheries and promote sustainable livelihoods in sub-Saharan Africa.