• Energy Research

Sustainable nitrogen (N) management in agriculture is one of the most important issues affecting the environmental performance of modern agriculture. It is actually well perceived that coordinated efforts and holistic approaches are required to regulate N use by farmers. The purpose of this study was to provide an initial examination of stakeholders’ views in Japan regarding N use in agriculture and challenges to increase its sustainability. The analysis was based on a questionnaire study of five types of stakeholders (farmers, advisors, researchers, suppliers, policy makers). By means of multivariate analysis techniques it was revealed that consensus was lacking either in the acknowledgment of the causes and effects of unsustainable N management or in the challenges that need to be addressed. N losses from farms and the effects of N use were perceived but not conceived equally by all stakeholders. Organic farming and mandatory measures were the most controversial challenges, while those involving awareness, training and advisory were the most popular. This study cannot provide safe conclusions that can be generalized in the Japanese context, but it indicates domains where further research is required and orientations for future policy design towards more sustainable N use.

Good soil quality implies the maintenance of properties at levels capable of ensuring an equilibrated and healthy ecosystem, with sustained agricultural production to supply the world population. Climate change, land-use change, and agriculture intensification are causing a decline in soil quality, which in most parts of the world is becoming severe (desertification). Land-use changes, the associated loss of soil organic matter (SOM), and beneficial microbial diversity are major reasons for deteriorating soil fertility and declining agricultural productivity, as well as affecting water, air, and biodiversity. Adaptation towards climate-resilient and climate-smart agriculture is necessary to cope with climate change and extreme events. This requires the following measures: (1) sustainable production (integrated livestock and cropping systems, including agroforestry); (2) increased soil organic matter (SOM) (bio-based and organic fertilizers, crop rotations, crop associations, no-till, conservation agriculture, C sequestration, and microbial processes); (3) reduced greenhouse gas emissions, less nutrient losses from agriculture, and increased nutrient use efficiency (NUE) (precision agriculture).