Mapping Flow-Obstructing Structures on Global Rivers

To help store water, facilitate navigation, generate energy, mitigate floods, and support industrial and agricultural production, people have built and continue to build obstructions to natural flow in rivers. However, due to the long and complex history of constructing and removing such obstructions, we lack a globally consistent record of their locations and types. Here, we used a consistent method to visually locate and classify obstructions on 2.1 million km of large rivers (width ≥30 m) globally. We based our mapping on Google Earth Engine’s high resolution images, which for many places have meter-scale resolution. The resulting Global River Obstruction Database (GROD) consists of 30,549 unique obstructions, covering six different obstruction types: dam, lock, low head dam, channel dam, and two types of partial dams. By classifying a subset of the obstructions multiple times, we are able to show high classification consistency (87% mean balanced accuracy) for the three types of obstructions that fully intersect rivers: dams, low head dams, and locks. The classification of the three types of partial obstructions are somewhat less consistent (61% mean balanced accuracy). Overall, by comparing GROD to similar datasets, we estimate GROD likely captured >90% of the obstructions on large rivers. We anticipate that GROD will be of wide interest to the hydrological modeling, aquatic ecology, geomorphology, and water resource management communities

A Picture of the Research Field of Doctoral Education from the Students’ Perspectives : Studies Using Questionnaires and Scales

Peer reviewe

The value of genetic resources in agriculture: a meta-analysis assessing existing knowledge and future research needs

The protection of genetic resources in agriculture is an important aspect of biodiversity conservation. Knowledge of the value of genetic resources can contribute to determining the appropriate focus and extent of conservation. This study reviewed and summarised literature on the economic value of genetic resources using meta-analysis. Altogether, 22 studies were used to describe current knowledge on the value of genetic resources. Furthermore, 14 studies with 93 value observations were examined with a meta-regression model to identify variables that explain the willingness-to-pay (WTP) for or willingness-to-accept (WTA) loss of genetic resources. Grain genetic resources were ascribed lower value compared to animal genetic resources (AnGR) and agrobiodiversity, and the values of breeds or varieties and conservation programmes were higher than the value of individual attributes. Future research should address the gaps in knowledge that are relevant for policy-making. This particularly includes improving knowledge on the value of plant genetic resources (PGR), obtaining value estimates for maintaining genetic diversity in Europe and the United States, estimating the relative magnitude of use and non-use values and determining the value consumers place on genetic resources and diversity in agriculture. An extensive database with valuation literature on genetic resources that fulfils the requirements for benefit transfer is essential to utilise value information more efficiently in decision-making situations.v2011o