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The inclusion of a specific natural disaster, hands-on models, and other multimedia experiences engaged students to learn about rivers and flooding. It was clear through verbal and written comments that students understood concepts related to flooding (water movement, land cover, etc.) and were able to reason with data--both their data from the stream tables and professionally collected data about river height and rainfall. These lessons provide many possibilities focused on community-relevant anchoring phenomena related to natural hazards, how human activity affects the incidence of these hazards, and how people can work toward reducing the occurrence, severity, and impact of natural hazards. 

To better quantify methane emissions resulting from grazing cattle, a controlled methane release at an agricultural site is performed using dual comb spectroscopy. The achieved methane concentration precision is below 10 nmol/mol. The Author(s) Work of the US Government and not subject to copyright.

 

Over a quarter of the world’s land surface is grazed by cattle and other livestock, which are replacing wild herbivores and widely regarded as drivers of global biodiversity declines. The effects of livestock presence versus absence on wild herbivores are well documented. However, the environmental context-specific effects of cattle stocking rate on biodiversity and livestock production are poorly understood, precluding nuanced rangeland management recommendations. To address this, we used a long term exclosure experiment in a semi-arid savanna ecosystem in central Kenya that selectively excludes cattle (at different stocking rates), wild mesoherbivores, and megaherbivores. We investigated the individual and interactive effects of cattle stocking rate (zero/moderate/high) and megaherbivore (>1,000 kg) accessibility on habitat use (measured as dung density) by two dominant wild mesoherbivores (50–1,000 kg; zebra Equus quagga and eland Taurotragus oryx ) across the “wet” and “dry” seasons. To explore potential tradeoffs or co-benefits between cattle production and wildlife conservation, we tested for individual and interactive effects of cattle stocking rate and accessibility by wild mesoherbivores and megaherbivores (collectively, large wild herbivores) on the foraging efficiency of cattle across both seasons. Eland habitat use was reduced by cattle at moderate and high stocking rates across both dry and wet seasons and regardless of megaherbivore accessibility. We observed a positive effect of megaherbivores on zebra habitat use at moderate, but not high, stocking rates. Cattle foraging efficiency (g dry matter step –1 min –1 ) was lower in the high compared to moderate stocking rate treatments during the dry season, and was non-additively reduced by wild mesoherbivores and high cattle stocking rates during the wet season. These results show that high stocking rates are detrimental to wild mesoherbivore habitat use and cattle foraging efficiency, while reducing to moderate stocking rates can benefit zebra habitat use and cattle foraging efficiency. Our findings demonstrate that ecosystem management and restoration efforts across African rangelands that involve reducing cattle stocking rates may represent a win-win for wild herbivore conservation and individual performance of livestock. 

Centuries of human development have altered the connectivity of rivers, adversely impacting ecosystems and the services they provide. Significant investments in natural resource projects are made annually with the goal of restoring function to degraded rivers and floodplains and protecting freshwater resources. Yet restoration projects often fall short of their objectives, in part due to the lack of systems‐based strategic planning. To evaluate channel‐floodplain (dis)connectivity and erosion/incision hazard at the basin scale, we calculate Specific Stream Power (SSP), an estimate of the energy of a river, using a topographically based, low‐complexity hydraulic model. Other basin‐wide SSP modeling approaches neglect reach‐specific geometric information embedded in Digital Elevation Models. Our approach leverages this information to generate reach‐specific SSP‐flow curves. We extract measures from these curves that describe (dis)connected floodwater storage capacity and erosion hazard at individual design storm flood stages and demonstrate how these measures may be used to identify watershed‐scale patterns in connectivity. We show proof‐of‐concept using 25 reaches in the Mad River watershed in central Vermont and demonstrate that the SSP results have acceptable agreement with a well‐calibrated process‐based model (2D Hydraulic Engineering Center's River Analysis System) across a broad range of design events. While systems‐based planning of regional restoration and conservation activities has been limited, largely due to computational and human resource requirements, measures derived from low‐complexity models can provide an overview of reach‐scale conditions at the regional level and aid planners in identifying areas for further restoration and/or conservation assessments.