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251.
252.
The use of adaptive cluster sampling for hydroacoustic surveys 总被引:5,自引:0,他引:5
253.
The Home Insulation Program (HIP) in Australia is an outstanding example of a contemporary attempt to intervene in a socio-technical regime. The program, implemented in 2009 under the then Australian Labor Party government led by Kevin Rudd, was targeted at stimulating the retrofit insulation industry. The objective was to both improve the energy efficiency of homes and thereby contribute to Australia’s emissions reduction targets by reducing greenhouse gas emissions and to stimulate the Australian economy at the time of the global financial crisis. The program ended early following a number of economic issues and health and safety concerns. Despite previous investigation into the HIP reviewing its design and implementation, the focus has been on economic issues and health and safety concerns. To date there has been no investigation of the HIP as a sustainability transition. This article integrates socio-technical transition theory (STTT) and political ecology (PE) approaches to analyse the HIP and identify lessons for future sustainability transition initiatives. This is achieved by illustrating the effect of regime management (RM) on the orientation of niche governance (NG) which highlights the importance of considering the RM and NG aspects of STTT with a PE approach in symmetry, in order to adequately account for political and economic contest and power relations, which are ubiquitous in environmental management governance. 相似文献
254.
Elizabeth M Cosper Charles F Wurster R George Rowland 《Marine environmental research》1984,12(3):209-223
A comparison between clones of two species of diatoms, Asterionella japonica and Ditylum brightwellii, isolated from Sandy Hook, New Jersey (polluted site) and Montauk, New York (unpolluted site) indicated that some of the clones from Sandy Hook were more resistant to polychlorinated biphenyls (PCB). A japonica was less sensitive to PCB than D. brightwellii since seven clones of A. japonica from both sites were tolerant of 25 μg litre?1 PCB whereas no clones from either site of D. brightwellii showed such resistance. Growth under high light intensity increased the sensitivity to PCB in all clones except one super-resistant clone from Sandy Hook which was not affected even by additions of 50 μg litre?1 to the growth medium. This interactive effect of light on PCB sensitivity may relate to the photo-adaptive characteristics of each clone. 相似文献
255.
DeWeese Nichole E. Favot Elizabeth J. Branstrator Donn K. Reavie Euan D. Smol John P. Engstrom Daniel R. Rantala Heidi M. Schottler Shawn P. Paterson Andrew M. 《Journal of Paleolimnology》2021,66(4):389-405
Journal of Paleolimnology - The spiny water flea (Bythotrephes cederströmii), a freshwater crustacean considered to be the world’s best-studied invasive zooplankter, was first recorded... 相似文献
256.
Although grasshoppers are common salt marsh herbivores, we know little about geographic variation in their species composition.
We documented latitudinal variation in species composition of the tettigoniid grasshopper fauna of Atlantic Coast salt marshes.
Tettigoniids (N = 740 adults) were collected from the Spartina alterniflora zone of 31 salt marsh sites across a latitudinal range of 13.19° (Florida to Maine), with an additional 52 individuals collected
from the Juncus roemerianus zone of low-latitude marshes for comparative purposes. Eight species were collected, but some were common only at a few sites
or rare throughout the entire collection range. The tettigoniid community was dominated by Orchelimum fidicinium at low latitudes and Conocephalus spartinae at high latitudes. Several factors might explain this shift, including changes in climate, plant phenology, and plant zonation
patterns. O. fidicinium and C. spartinae increased in body size toward low latitudes. In laboratory feeding assays, O. fidicinium readily ate S. alterniflora and J. roemerianus leaves, Orchelimum concinnum, which is largely restricted to the J. roemerianus zone, ate only J. roemerianus leaves, and Conocephalus spp. ate neither, consistent with literature suggestions that they mainly consume seeds and flowers. Geographic variation
in species composition and body size of grasshoppers may help explain documented patterns of geographic variation in plant
palatability and plant–herbivore interactions in Atlantic Coast salt marshes. Because it can be difficult to identify tettigoniids
to species, we present a guide to aid future workers in identifying the tettigoniid species common in these marshes. 相似文献
257.
Michael A. Poirrier Zoe Rodriguez del Rey Elizabeth A. Spalding 《Estuaries and Coasts》2008,31(6):1221-1228
In 2005, Hurricane Katrina produced a distinct, acute ecological disturbance of the benthic invertebrate community of Lake
Pontchartrain, LA, USA. The bivalve Rangia cuneata and other community dominants were lost from 50% (815 km2) of the lake bottom. The storm surge directly killed benthic organisms and produced salinity stratification that caused episodes
of detrimental low dissolved oxygen concentration at depths >3.7 m. Past disturbance of the bottom by shell dredging and intrusion
of higher salinity bottom water through deep shipping channels appears to have contributed to the severity of this impact.
Colonization by tolerant opportunistic taxa occurred, but low rainfall after Katrina has slowed the recovery of the typical
rangia community. A decrease in water transparency and an increase in turbidity and chlorophyll a were associated with the loss of clam biomass. Other hurricanes may have produced less obvious but similar effects on smaller
spatial and temporal scales. 相似文献
258.
Community surveys have been widely used to investigate local residents’ perceptions and behaviors related to natural resource issues. However, most existing community survey research relies on cross-sectional data and is thus unable to capture the temporal dynamics of community processes. Longitudinal analysis has received increasing interest in recent natural resource social science literature. Trend and panel studies are two typical approaches in longitudinal community survey research. Due to limited sampling frames, research design, and respondent attrition, longitudinal community surveys often involve both paired and independent observations across different survey waves. Using previous survey data on community responses to forest insect disturbance in Alaska as an example, this research note shows that the corrected z-test is a more appropriate approach to analyze partially correlated longitudinal data than conventional statistical techniques such as the paired and independent t-tests. 相似文献
259.
260.