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Snow pole time‐lapse photography, in which a snow pole of a known height is installed in front of a camera and photographed repeatedly over the course of a snow season, allows a large network of sites to be established relatively quickly and affordably. However, current approaches for extracting snow depth from snow poles typically relies on time intensive manual photo processing. By integrating computer vision algorithms with snow pole photography, we present a method that uses a keypoint detection model to automatically observe snow height across a network of sites. At 20 snow pole locations from Grand Mesa, CO (n = 9,722 images), our model successfully predicts the top and bottom of the pole with a mean absolute error (MAE) of 1.30 cm. To assess model generalizability, we tested the model on 12 sites in Washington State (n = 1,770 images). When the Colorado trained model was fine‐tuned using a subset of Washington images, the model predicted snow depth with a MAE of 4.0 cm. Best performance was achieved when both data sets were included during training, with a MAE of 2.05 cm for Colorado images and a MAE of 1.14 cm for Washington images. We demonstrate that, especially when trained using a subset of site‐specific data, a keypoint detection model can accelerate snow pole automation. This algorithm brings the hydrology community one step closer to a generalized snow pole detection model, and we call for a future model that integrates across time‐lapse images from additional locations. Plain Language Summary: Snow scientists depend on accurate snow depth measurements for water planning and snow modeling. Time‐lapse cameras are inexpensive, can be installed for months at a time in remote regions when winter access may be difficult, and can be programmed to take multiple images a day throughout the winter. However, these cameras often generate thousands of images that require processing to extract snow depth. Here, we develop a keypoint detection model to facilitate automating the process of snow depth extraction from snow poles installed in front of time‐lapse cameras. We expand upon previous approaches to predict the length in pixels, then use pixel to centimeter conversions to extract the snow depth in centimeters. We provide a framework for future analysis of snow depth from time‐lapse imagery, helping to improve snow depth monitoring and forecasting. Key Points: A keypoint detection model to automate snow depth measurements with a mean absolute error equal to 1.14 cm is introducedMethod shows accuracy for snow depth both in and out of canopy locations and throughout the winter seasonWhen "fine‐tuned" using 10 images per camera, the model achieves accuracy within 4 cm on a novel network comprising 12 cameras [ABSTRACT FROM AUTHOR]

The central position of water in social and economic development drives the imperative for water storage, particularly in water-stressed parts of the world. A consequence is that rivers are perceived primarily as locations for water storage as we seek to manage risks to social welfare and development. Assurance of supply becomes the dominant paradigm shaping decisions about allocation of water from impoundments. When this paradigm is deeply ingrained it constrains decision-making around flow management for other purposes, particularly for sustaining ecological systems. Ten years ago South Africa introduced progressive legislation for water resource management (the National Water Act of 1998) which enshrines the ecological Reserve. This requirement for the environment is not considered as a water use, because the environment is the resource. However, due to the very complex Reserve determination process, and perhaps a lack of political will, the ecological Reserve has proved difficult to implement and has only now started to be implemented in some river systems. In the case of the lower uMngeni River in KwaZulu-Natal, besides releases to maintain a minimum river flow (the so called 'compensation flows', which were never designed as environmental flows), for nearly 20 years there has been an unofficial policy to allow spates on between 1 and 4 days per year to make possible the continuation of the prestigious Dusi Canoe Marathon. The total amount of water involved is just over 1.2% of the river's virgin MAR, although in years perceived to be dry the releases may be cut to as little as 0.3% of the virgin MAR. While these releases have been tolerated for the continuation of a high-value recreational industry, they are in fact aligned, albeit with a fraction of the necessary volume, with the environmental flows that would be required if the ecological Reserve had been determined. The releases for these events therefore have a dual or conjunctive value, serving both environmental and recreational purposes at the same time. We suggest that considerations of conjunctive use offer practical opportunities for balancing resource protection and development in regulated rivers. [ABSTRACT FROM AUTHOR]

This is a study of a community-based fishery on the Rovuma River that forms the border between Mozambique and Tanzania. We postulate a relationship between social capital and community-based governance over access to and the use of the fish resource. In historical times social capital was high and community-based governance regulated access to and use of the fishery as a common property resource. Transforming forces particularly colonial administration, advocating Christianity, war and an emerging market economy undermined social capital, which in turn affected community-based governance. The deconstruction of social capital has resulted in attitudes and behaviours that challenge governance processes with dire consequences for sustainable resource utilisation. Harvesting of fish stocks occurs at levels that are no longer sustainable and inappropriate practices are being adopted. While the Mozambique government policy promotes community-based fisheries management in artisanal fisheries, we argue that under current conditions of ineffective community-based governance, a strong focus on reconstruction of social capital will be required before a community-based resource management process can be effectively implemented. The findings are discussed in the context of resilience in social ecological systems. We suggest that given the historical context in which community-based natural resource management is promoted within southern Africa such a focus may have wide relevance. [ABSTRACT FROM AUTHOR]

Objective: To determine the incidence and nature of interpersonal conflicts that arise when patients in the intensive care unit are considered for limitation of life-sustaining treatment.Design: Qualitative analysis of prospectively gathered interviews.Setting: Six intensive care units at a university medical center.Participants: Four hundred six physicians and nurses who were involved in the care of 102 patients for whom withdrawal or withholding of treatment was considered.Measurements: Semistructured interviews addressed disagreements during life-sustaining treatment decision making. Two raters coded transcripts of the audiotaped interviews.Main Results: At least 1 health care provider in 78% of the cases described a situation coded as conflict. Conflict occurred between the staff and family members in 48% of the cases, among staff members in 48%, and among family members in 24%. In 63% of the cases, conflict arose over the decision about life-sustaining treatment itself. In 45% of the cases, conflict occurred over other tasks such as communication and pain control. Social issues caused conflict in 19% of the cases.Conclusions: Conflict is more prevalent in the setting of intensive care decision making than has previously been demonstrated. While conflict over the treatment decision itself is most common, conflict over other issues, including social issues, is also significant. By identifying conflict and by recognizing that the treatment decision may not be the only conflict present, or even the main one, clinicians may address conflict more constructively. [ABSTRACT FROM AUTHOR]

The location, physiography and climate of the dune forest in the vicinity of Lake Sibayi is given. The general ecology of the forest, with particular reference to composition and density of trees and shrubs, is outlined. The results are discussed in relation to survival of the most important canopy trees. It is concluded that the forest represents a stable vegetation type, i.e. Climax Dune Forest. A preliminary list of plants collected in the dune forest is appended. [ABSTRACT FROM PUBLISHER]

A mass mortality of mangroves occurred in the Kosi estuary in 1965. Events leading up to the mortality were investigated and it was concluded that flooding of the estuary following upon closure of the mouth for five months was responsible. The existing distribution of mangroves, both dead and alive, was recorded and the percentage survival of the various species was determined by means of counts. It was found that mangroves on high ground, chiefly Lumnitzera racemosa Willd., had survived. It appeared that Bruguiera gymnorrhiza (L.) Lam. would probably become the dominant mangrove in the intertidal zone in the future, although Avicennia marina (Forsk.) Vierh. and Rhizophora mucronata Lam. would not disappear from the estuary. [ABSTRACT FROM PUBLISHER]