Shapes of Hyperspectral Imaged Microplastics.

Shape matters for microplastics, but its definition, particularly for hyperspectral imaged microplastics, remains ambiguous and inexplicit, leading to incomparability across data. Hyperspectral imaging is a common approach for quantification, yet no unambiguous microplastic shape classification exists. We conducted an expert-based survey and proposed a set of clear and concise shapes (fiber, rod, ellipse, oval, sphere, quadrilateral, triangle, free-form, and unidentifiable). The categories were validated on images of 11,042 microplastics from four environmental compartments (seven matrices: indoor air; wastewater influent, effluent, and sludge; marine water; stormwater; and stormwater pond sediments), by inviting five experts to score each shape. We found that the proposed shapes were well defined, representative, and distinguishable to the human eye, especially for fiber and sphere. Ellipse, oval, and rod were though less distinguishable but dominated in all water and solid matrices. Indoor air held more unidentifiable, an abstract shape that appeared mostly for particles below 30 µm. This study highlights the need for assessing the recognizability of chosen shape categories prior to reporting data. Shapes with a clear and stringent definition would increase comparability and reproducibility across data and promote harmonization in microplastic research.

Participatory mapping of cultural ecosystem services for landscape corridor planning: A case study of the Silk Roads corridor in Zhangye, China.

Cultural landscape corridors provide opportunities for recreation and other cultural ecosystem services (CES). Currently, many local governments are preparing cultural landscape corridor (CLC) proposals along China's Silk Roads, which include many notable features of historical human activity and communication between different cultures. However, public values and perceptions of these projects have been largely excluded from the planning processes. This study presents a spatial pattern analysis of public perceptions of the impact of a CLC in Zhangye, China. CES were used as a framework for participatory mapping, interviews, and a structured survey of public perceptions, and correspondence analysis was used to identify resident perceptions of the corridor's expected impact, especially as related to CES. Our results show that aesthetic values, cultural heritage values, and recreation were valued most highly. These values varied according to respondents' employment and land-use rights. The riverside was the most highest-valued area for CES. Respondents expressed concerns about the project's potentially negative impact, especially on the spiritual values of land. These concerns could be the source of conflict during project implementation. We conclude that linking participatory mapping with CES has the potential to improve corridor proposals and assist in the management of conflicts between planners and public stakeholders.