Despite its large acreage, riparian wetland has been underutilized in Indonesia. Intensity of agricultural activities on this wetland was very low mainly due to two unfavorable extremes, i.e. unpredictable occurrence of flooding during rainy season and drought during dry season. Relevant, affordable, and acceptable technologies are required as solution to this problems. The technologies should be developed based on actual needs, preferences, and absorptive capacity of smallholder farmers, to ensure adoption. Objective of this study was to explore needs, preferences, and absorptive capacity of smallholder farmers through direct observation on their farming practices and dialogs on constraints in intensifying food production at riparian wetlands in Indonesia. The study was conducted at five villages in riparian wetland ecosystem in South Sumatera, Indonesia, from January to June 2016. This qualitative research was conducted in two stages: started with no-preconception Grounded Theory procedure; then, followed by questionnaire-guided survey. Results of this study indicated that intensive observation on farmer's practices and dialogs on constraints in intensifying food production could reveal needs, preferences, and absorptive capacity of smallholder farmers. Observed farmers' practices include land preparation and soil quality improvement, seedling preparation, transplanting, cropping management, and harvesting. Dialogs disclosed that unmanageable constraint but urgently needed by smallholder farmers in intensifying food production was technology solution for uncertain and uncontrollable natural flooding and drought occurrence at riparian wetlands. Government intervention is expected for constructing infrastructure for water management at riparian wetlands, i.e. polder system.

Biochar improves soil quality. However, most biochar research has focused on aerobic soil conditions. The objective of this research was to evaluate the agronomic benefits of applying biochar on unfertilized rice crop, cultivated under transitional anaerobic soil conditions during early vegetative growth phase, and gradually drying out to fully aerobic at harvest time. This transitional condition is typical during the rice growing season of the tropical riparian wetlands in Indonesia. Biochar was applied in the form of fine powder at rates of 0, 0.4, 0.8, and 1.2 Mg.ha -1 ; no inorganic fertilizer was applied. The research was conducted on a farmer's paddy field at Pemulutan Ulu Village, South Sumatra, Indonesia from July to November 2016. Results indicated that applying biochar at rates up to 1.2 Mg.ha -1 increased rice yield, but restrained shoot elongation rate and plant height. During the vegetative growth phase, applying biochar significantly increased the number of tillers, leaves, shoot dry weight, and root dry weight. Biochar significantly affected the following yield components: number of tillers, percentage of productive tiller, number of grains per panicle, panicle density, percentage of filled grain, and weight of 1,000 grains.

Productivity and cropping intensity on non-tidal wetland in South Sumatra are considerably low and has been underutilized up to now. The majority of farmers in this ecosystem are smallholders with limited adoption capacity on introduced technologies and modern agricultural practices. The objectives of this research were (1) to comprehensively capture multidimensional constrains that restrained local farmers in increasing their agricultural productivity; and (2) to identify, assess, and develop substantially-relevant, financially-affordable, and sociallyacceptable agricultural technologies and practices for smallholder farmers to increase productivity. This research was organized in three main activities: qualitative research employing Grounded Theory procedure, quantitative questionnaire-guided survey, and a series of laboratory and field experiments. The research results indicated that the main constraints in increasing productivity and cropping intensity on the non-tidal wetland in South Sumatra include (1) unpredictable flooding occurrence and low soil nutrients content (agronomic constraint), (2) low financial and technology adoption capacity of local farmers (economic constraint), and (3) public policy has not significantly escalated farmer's motivation to increase food production (social and institutional constraint). This research suggests that multidimensional (technical, financial, ecological, and socio-cultural) approaches should be integrated in collective efforts for sustainably intensifying food production on the non-tidal wetland.