No abstract

Buffer zones, established between agricultural fields and water bodies, are widely used as a measure to reduce N in surface runoff and groundwater. However, the literature indicates inconsistent results on the N removal efficiency of buffer zones between studies. We performed a weighed meta-analysis on the buffer zone effects on NO 3 -N and total N in surface runoff and groundwater by summarizing 46 studies published between 1980 and 2017. The overall effects of buffer zones were a 33 (−48 to −17%, n = 25) and 70% (−78 to −62%, n = 38) NO 3 -N reduction in surface runoff and in groundwater, respectively, compared with controls with no buffer zone. In addition, buffer zones reduced the total N in surface runoff by 57% (−68 to −43%, n = 16). The effects of buffer zones on N retention were consistent across continents and in different climates. Nitrogen retention increased with increasing initial N concentrations discharged from the source of pollution. According to a meta-regression, the N removal efficiency in surface runoff decreased in consort with increasing buffer zone age. Otherwise, the meta-analysis revealed no effects of buffer zone characteristics such as the width or species number (for grass buffer zones) on the N retention in surface runoff and groundwater. Unlike groundwater quality, which responded equally well regardless of the source of pollution, buffer zone type, or buffer zone age, surface water quality is more sensitive, and it might not be satisfactorily improved by tree buffer zones or aged buffer zones, or when the source of pollution originates from grass production fields.

No abstract

No abstract

In environmental management and sustainability there is an increasing interest in measurement and accounting of beneficial impact-as an incentive to action, as a communication tool, and to move toward a positive, constructive approach focused on opportunities rather than problems. One approach uses the metaphor of a "handprint," complementing the notion of environmental footprints, which have been widely adopted for impact measurement and accounting. We analyze this idea by establishing core principles of handprint thinking: Handprint encourages actions with positive impacts and connects to analyses of footprint reductions but adds value to them and addresses the issue of what action should be taken. We also identify five key questions that need to be addressed and decisions that need to be made in performing a (potentially quantitative) handprint assessment, related to scoping of the improvement to be made, how it is achieved, and how credit is assigned, taking into account constraints on action. A case study of the potential water footprint reduction of an average Finn demonstrates how handprint thinking can be a natural extension of footprint reduction analyses. We find that there is a diversity of possible handprint assessments that have the potential to encourage doing good. Their common foundation is "handprint thinking." Plain Language Summary The "handprint" has been suggested as a way of looking at the good we do, to complement the negative impacts captured by environmental "footprints." There are many ways we could try to assess a handprint, which capture different perspectives on the world, and the potential role of the handprint assessment in moving toward sustainability. This paper cuts down the definition of a handprint to three core principles and then discusses five questions that need to be considered and the decisions that need to be made in designing or evaluating a handprint assessment. A case study looks at how an average Finnish consumer can reduce the water footprint of the food they eat.