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81.
Charles G. Morton Justin L. Huntington Greg M. Pohll Richard G. Allen Kenneth C. McGwire Scott D. Bassett 《Journal of the American Water Resources Association》2013,49(3):549-562
Agricultural irrigation accounts for a large fraction of the total water use in the western United States. The Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) remote sensing energy balance model is being used to estimate historical agricultural water use in western Nevada to evaluate basin‐wide water budgets. Each METRIC evapotranspiration (ET) estimate must be calibrated by a trained user, which requires some iterative time investment and results in variation in ET estimates between users. An automated calibration algorithm for the METRIC model was designed to generate ET estimates comparable to those from trained users by mimicking the manual calibration process. Automated calibration allows for rapid generation of METRIC ET estimates with minimal manual intervention, as well as uncertainty and sensitivity analysis of the model. The variation in ET estimates generated by the automated calibration algorithm was found to be similar to the variation in manual ET estimates. Results indicate that uncertainty was highest for fields with low ET levels and lowest for fields with high ET levels, with a seasonal mean uncertainty of approximately 5% for all fields. In addition, in a blind comparison, automated daily and seasonal ET estimates compared well with flux tower measurement ET data at multiple sites. Automated methods can generate first‐order ET estimates that are similar to time intensive manual efforts with less time investment. 相似文献
82.
Resource planning and management in British Columbia, Canada, has been steadily moving towards more active public participation. While government agencies have long been required to consult the general public during the course of land or resource use planning, the 1990s brought in a period of more intense public involvement. In terms of resource planning, this led to the creation of several new planning processes. Given that there is now considerable experience with the Commission on Resources and Environment (CORE) and the Land and Resource Management Plan (LRMP) processes, it is time for an appraisal. In particular, the paper examines the public's perceptions of these processes with respect to 'what works well' and 'what needs improvement'. The results highlight a number of areas to which process designers and managers should direct attention. There are three key items of note. First, there are generally low levels of awareness by respondents of public consultation processes in their community. Second, there is a need for access to timely, relevant and readable information throughout the course of the process in order to keep participants and the public as up-to-date as possible. Finally, there must be greater clarity about the process itself, including mandates, participants and decision-making powers. 相似文献
83.
Potential Economic Benefits of Adapting Agricultural Production Systems to Future Climate Change 总被引:2,自引:0,他引:2
Tony Prato Qiu Zeyuan Gregory Pederson Dan Fagre Lindsey E. Bengtson Jimmy R. Williams 《Environmental management》2010,45(3):577-589
Potential economic impacts of future climate change on crop enterprise net returns and annual net farm income (NFI) are evaluated
for small and large representative farms in Flathead Valley in Northwest Montana. Crop enterprise net returns and NFI in an
historical climate period (1960–2005) and future climate period (2006–2050) are compared when agricultural production systems
(APSs) are adapted to future climate change. Climate conditions in the future climate period are based on the A1B, B1, and
A2 CO2 emission scenarios from the Intergovernmental Panel on Climate Change Fourth Assessment Report. Steps in the evaluation include:
(1) specifying crop enterprises and APSs (i.e., combinations of crop enterprises) in consultation with locals producers; (2)
simulating crop yields for two soils, crop prices, crop enterprises costs, and NFIs for APSs; (3) determining the dominant
APS in the historical and future climate periods in terms of NFI; and (4) determining whether NFI for the dominant APS in
the historical climate period is superior to NFI for the dominant APS in the future climate period. Crop yields are simulated
using the Environmental/Policy Integrated Climate (EPIC) model and dominance comparisons for NFI are based on the stochastic
efficiency with respect to a function (SERF) criterion. Probability distributions that best fit the EPIC-simulated crop yields
are used to simulate 100 values for crop yields for the two soils in the historical and future climate periods. Best-fitting
probability distributions for historical inflation-adjusted crop prices and specified triangular probability distributions
for crop enterprise costs are used to simulate 100 values for crop prices and crop enterprise costs. Averaged over all crop
enterprises, farm sizes, and soil types, simulated net return per ha averaged over all crop enterprises decreased 24% and
simulated mean NFI for APSs decreased 57% between the historical and future climate periods. Although adapting APSs to future
climate change is advantageous (i.e., NFI with adaptation is superior to NFI without adaptation based on SERF), in six of
the nine cases in which adaptation is advantageous, NFI with adaptation in the future climate period is inferior to NFI in
the historical climate period. Therefore, adaptation of APSs to future climate change in Flathead Valley is insufficient to
offset the adverse impacts on NFI of such change. 相似文献
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