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961.
Will Allen Shaun Ogilvie Helen Blackie Des Smith Shona Sam James Doherty Don McKenzie James Ataria Lee Shapiro Jamie MacKay Elaine Murphy Chris Jacobson Charles Eason 《Environmental management》2014,53(2):429-440
The success of research in integrated environmental and natural resource management relies on the participation and involvement of different disciplines and stakeholders. This can be difficult to achieve in practice because many initiatives fail to address the underlying social processes required for successful engagement and social learning. We used an action research approach to support a research-based group with a range of disciplinary and stakeholder expertise to critically reflect on their engagement practice and identify lessons around how to collaborate more effectively. This approach is provided here as a guide that can be used to support reflective research practice for engagement in other integration-based initiatives. This paper is set in the context of an integrated wildlife management research case study in New Zealand. We illustrate how multi-, inter- and trans-disciplinary approaches can provide a framework for considering the different conversations that need to occur in an integrated research program. We then outline rubrics that list the criteria required in inter- and trans-disciplinary collaborations, along with examples of effective engagement processes that directly support integration through such efforts. Finally, we discuss the implications of these experiences for other researchers and managers seeking to improve engagement and collaboration in integrated science, management and policy initiatives. Our experiences reaffirm the need for those involved in integrative initiatives to attend to the processes of engagement in both formal and informal settings, to provide opportunities for critical reflective practice, and to look for measures of success that acknowledge the importance of effective social process. 相似文献
962.
Guangping Qie Zhenxing Zhang Elias Getahun Emily Allen Mamer 《Journal of the American Water Resources Association》2023,59(3):554-570
Reservoir outflow is an important variable for understanding hydrological processes and water resource management. Natural streamflow variation, in addition to the streamflow regulation provided by dams and reservoirs, can make streamflow difficult to understand and predict. This makes them a challenge to accurately simulate hydrologic processes at a daily scale. In this study, three Machine Learning (ML) algorithms, Random Forest (RF), Support Vector Machine (SVM), and Artificial Neural Network (ANN), were examined and compared to model reservoir outflow. Past, current, and future hydrologic and meteorological data were used as model inputs, and the outflow of next day was used as prediction. Simulation results demonstrated that all three models can reasonably simulate reservoir outflow. For Carlyle Lake, the coefficient of determination and Nash–Sutcliffe efficiency were each close to one for the three models. The coefficient of determination, relative mean bias, and root mean square error indicated that the SVM performed better than the RF and ANN, but the SVM output displayed a larger relative mean bias than that from RF and ANN. For Lake Shelbyville, the ANN model performed better than RF and SVM when considering the coefficient of determination, Nash–Sutcliffe efficiency, relative mean bias, and root mean square error. The study results demonstrate that the three ML algorithms (RF, SVM, and ANN) are all promising tools for simulating reservoir outflow. Both the accuracy and efficacy of the three ML algorithms are considered to support practitioners in planning reservoir management. 相似文献
963.
Heavy metal fates in laboratory bioretention systems 总被引:5,自引:0,他引:5
Key to managing heavy metals in bioretention is to understand their fates in bioretention facilities. In this study, pot prototypes filled with bioretention media were built to simulate the conditions of natural growth of plants. Synthetic runoff with different heavy metal loadings (copper, cadmium, lead, and zinc) was periodically applied. Metal accumulations in tissues of grasses -Panicum virgatum, Kentucky-31, and Bromus ciliatus, were investigated after 230d of growth and multiple runoff treatment events. After 183d of periodic runoff application, the concentrations of Zn, Cu, Pb and Cd with low and high loadings had the same trends in the plant tissues, Zn>Cu>Pb>Cd, following the trend of the input metal concentrations. The fates of input metals were 88-97% captured in soil media, 2.0-11.6% not captured by bioretention media, and 0.5-3.3% accumulated in plants. Compared to the metals retained by the soil, the percentages of input metals taken up by plants were relatively low due to the low plant biomass produced in this study. Greater biomass density would be required for the vegetation to have a valuable impact in prolonging the lifetime of a bioretention cell. 相似文献
964.
Dirac Twidwell Carissa L. Wonkka Christine H. Bielski Craig R. Allen David G. Angeler Jacob Drozda Ahjond S. Garmestani Julia Johnson Larkin A. Powell Caleb P. Roberts 《Conservation biology》2018,32(4):905-915
A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus. 相似文献
965.
Ryan W. Allen Sara Leckie Gail Millar Michael Brauer 《Atmospheric environment (Oxford, England : 1994)》2009,43(37):5908-5915
Fine particulate matter (PM2.5) air pollution has been linked to adverse health impacts, and combustion sources including residential wood-burning may play an important role in some regions. Recent evidence suggests that indoor air quality may improve in homes where older, non-certified wood stoves are exchanged for lower emissions EPA-certified alternatives. As part of a wood stove exchange program in northern British Columbia, Canada, we sampled outdoor and indoor air at 15 homes during 6-day sampling sessions both before and after non-certified wood stoves were exchanged. During each sampling session two consecutive 3-day PM2.5 samples were collected onto Teflon filters, which were weighed and analyzed for the wood smoke tracer levoglucosan. Residential PM2.5 infiltration efficiencies (Finf) were estimated from continuous light scattering measurements made with nephelometers, and estimates of Finf were used to calculate the outdoor- and indoor-generated contributions to indoor air. There was not a consistent relationship between stove technology and outdoor or indoor concentrations of PM2.5 or levoglucosan. Mean Finf estimates were low and similar during pre- and post-exchange periods (0.32 ± 0.17 and 0.33 ± 0.17, respectively). Indoor sources contributed the majority (~65%) of the indoor PM2.5 concentrations, independent of stove technology, although low indoor-outdoor levoglucosan ratios (median ≤ 0.19) and low indoor PM2.5-levoglucosan correlations (r ≤ 0.19) suggested that wood smoke was not a major indoor PM2.5 source in most of these homes. In summary, despite the potential for extensive wood stove exchange programs to reduce outdoor PM2.5 concentrations in wood smoke-impacted communities, we did not find a consistent relationship between stove technology upgrades and indoor air quality improvements in homes where stoves were exchanged. 相似文献
966.
Musa Bandowe BA Sobocka J Wilcke W 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):539-549
We determined concentrations, sources, and vertical distribution of OPAHs and PAHs in soils of Bratislava. The ∑14 OPAHs concentrations in surface soil horizons ranged 88-2692 ng g−1 and those of ∑34 PAHs 842-244,870 ng g−1. The concentrations of the ∑9 carbonyl-OPAHs (r = 0.92, p = 0.0001) and the ∑5 hydroxyl-OPAHs (r = 0.73, p = 0.01) correlated significantly with ∑34 PAHs concentrations indicating the close association of OPAHs with parent-PAHs. OPAHs were quantitatively dominated by 9-fluorenone, 9,10-anthraquinone, 1-indanone and benzo[a]anthracene-7,12-dione. At several sites, individual carbonyl-OPAHs had higher concentrations than parent PAHs. The concentration ratios of several OPAHs to their parent-PAHs and contribution of the more soluble OPAHs (1-indanone and 9-fluorenone) to ∑14 OPAHs concentrations increased with soil depth suggesting that OPAHs were faster vertically transported in the study soils by leaching than PAHs which was supported by the correlation of subsoil:surface soil ratios of OPAH concentrations at several sites with KOW. 相似文献
967.
Four often fetuses carrying a risk of 1:4 for cystic fibrosis were found to have low levels of microvillar enzymes in the amniotic fluid obtained between 17 and 18 weeks' gestational age. On sonography performed prior to the amniocentesis, three fetuses showed enlarged bowel loops. At autopsy, meconium ileus was detected. Enlarged bowel loops are a sign which has not been described previously so early in pregnancies. 相似文献
968.
While foraging, social insects encounter a dynamic array of food resources of varying quality and profitability. Because food
acquisition influences colony growth and fitness, natural selection can be expected to favor colonies that allocate their
overall foraging effort so as to maximize their intake of high-quality nutrients. Social wasps lack recruitment communication,
but previous studies of vespine wasps have shown that olfactory cues influence foraging decisions. Odors associated with food
brought into the nest by successful foragers prompt naive foragers to leave the nest and search for the source of those odors.
Left unanswered, however, is the question of whether naive foragers take food quality into account in making their decisions
about whether or not to search. In this study, two different concentrations of sucrose solutions, scented differently, were
inserted directly into each of three Vespula germanica nests. At a feeder away from the nest, arriving foragers were given a choice between two 1.5 M sucrose solutions with the
same scents as those in the nest. We show that wasps chose higher-quality resources in the field using information in the
form of intranidal food-associated odor cues. By this simple mechanism, the colony can bias the allocation of its foraging
effort toward higher-quality resources in the environment. 相似文献
969.
Arthur R. Bos Girley S. Gumanao Marieke M. van Katwijk Benjamin Mueller Marjho M. Saceda Rosie Lynn P. Tejada 《Marine Biology》2011,158(3):639-648
Archaster typicus, a common sea star in Indo-Pacific regions, has been a target for the ornamental trade, even though little is known about
its population biology. Spatial and temporal patterns of abundance and size structure of A. typicus were studied in the Davao Gulf, the Philippines (125°42.7′E, 7°0.6′N), from February 2008 to December 2009. Specimens of
A. typicus were associated with intertidal mangrove prop roots, seagrass meadows, sandy beaches, and shoals. Among prop roots, specimens
were significantly smaller and had highest densities (131 ind. m−2) between November and March. High organic matter in sediment and a relatively low predation rate seemed to support juvenile
life among mangroves. Size and density analyses provided evidence that individuals gradually move to seagrass, sandy habitats,
and shoals as they age. Specimens were significantly larger at a shoal (maximum radius R = 81 mm). New recruits were found between August and November in both 2008 and 2009. Timing of recruitment and population
size frequencies confirmed a seasonal reproductive cycle. Juveniles had relatively high growth rates (2–7 mm month−1) and may reach an R of 20–25 mm after 1 year. Growth rates of larger specimens (R > 30 mm) were generally <2 mm month−1. The activity pattern of A. typicus was related to the tidal phase and not to time of day: Specimens moved over the sediment surface during low tides and were
burrowed during high tides possibly avoiding predation. This is one of the first studies to document an ontogenetic habitat
shift for sea stars and provides new biological information as a basis for management of harvested A. typicus populations. 相似文献
970.
Thomas C. Brown Benjamin L. Harding William B. Lord 《Journal of the American Water Resources Association》1988,24(4):801-814
ABSTRACT: This study examined the disposition of streamflow increases that could be created by vegetation management on forest land along the upper reaches of the Colorado River. A network optimization model was used to simulate water flow, storage, consumptive use, and loss within the entire Colorado River Basin with and without the flow increases, according to various scenarios incorporating both current and future consumptive use levels as well as existing and potential institutional constraints. Results indicate that very little of the flow increases would be consumptively used at current use levels, or even at future use levels, if water allocation institutions remain unchanged. Given future use levels and economically based water allocation institutions, up to one-half of the flow increases could be consumptively used. The timing of streamflow increases, and the institutional constraints on water allocation, often limit the potential for consumptive use of flow increases. 相似文献