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11.
Collaborative policy making has become increasingly significant in environmental management, but it is often evaluated by whether or not agreement is reached and implemented. The most important outcomes of such policy dialogues are often invisible or undervalued when seen through the lens of a traditional, modernist paradigm of government and accountability. These dialogues represent a new paradigm of governance that can be best understood in the light of a complex adaptive system model of society. From this perspective collaborative policy making is a way of making a system more flexible, adaptive and intelligent. The authors document such outcomes in three cases of water policy making in California, including the San Francisco Estuary Project, the CALFED Bay-Delta Program and the Sacramento Area Water Forum. The outcomes include social and political capital, agreed-on information, the end of stalemates, high-quality agreements, learning and change, innovation and new practices involving networks and flexibility. 相似文献
12.
V. Thomas Parker 《Conservation biology》2002,16(5):1444-1446
13.
Effluent from dyeing and finishing processes is an important source of water pollution. The effectiveness of bentonite, kaolinite and sediment from a local deposit in removing methylene blue as a cationic dye from aqueous solutions has been investigated. The adsorption equilibrium (isotherm) has been determined according to Freundlich and Langmuir equations. The optimum amount is 0.5 g for all adsorbents, and the optimum pH ranges are 2-8 for bentonite and 2-6 for kaolinite and sediment. With respect to kinetic modelling, the adsorption of methylene blue on various adsorbents was fitted to a second-order equation. Also, the thermodynamic parameters were determined. The negative free energy values indicate the feasibility of the process and spontaneous nature of adsorption. The positive ΔH° values indicate the endothermic nature of the process. Thus, Egyptian clay minerals and sediments have a great tendency to remove the dye from solutions. 相似文献
14.
The typical parameters of acid precipitation are evaluated in the forest of Vallombrosa (Tuscan Appennines) during the dry period 1988-89. Individual rain events (dry and wet deposition) were sampled in a clearing of the forest and below the canopy of an evergreen tree as well as a deciduous broadleaf tree.
In atmospheric precipitation the pH values usually vary around 4.4, with neutralization in the hot season due to calcareous material from distant sources. Relatively large concentrations of Pb and Cd are found in rain, but only in a small amount in canopy leachate. Aluminium, manganese and iron are more significantly washed off than Pb and Cd. 相似文献
In atmospheric precipitation the pH values usually vary around 4.4, with neutralization in the hot season due to calcareous material from distant sources. Relatively large concentrations of Pb and Cd are found in rain, but only in a small amount in canopy leachate. Aluminium, manganese and iron are more significantly washed off than Pb and Cd. 相似文献
15.
16.
M. Marcelli M. Caburazzi A. Perilli V. Piermattei E. Fresi 《Chemistry and Ecology》2005,21(5):351-367
The towed undulating vehicle (TUV), named SARAGO, was used for two fine-scale surveys between the Italian and the Sardinian coasts during the Astraea 2 cruise (6-7 and 26-27 September 1995), studying the deep chlorophyll maximum distribution. SARAGO sections identify a sub-surface doming with higher chlorophyll a and primary production concentrations in the upwelling area of a cyclonic gyre region, detected by sea-surface temperature images. In the first section, the cyclone presents a double doming, in density and salinity, with shallower and concentrated patches of chlorophyll a for about 2 miles. Twenty days later, the second section shows that the gyre changes shape and extension, showing a single doming with higher primary production and chlorophyll a concentrations, distributed over a large area of about 40 nautical miles. SARAGO allows analysis of this high-variability phenomenon (cyclonic gyre) and allows concentrated patches (2 nm) to be identified, thus proving the importance of TUVs in the study of mesoscale processes. 相似文献
17.
This paper reviews six case studies examined as part of a project to review targetting methodologies employed by non-government organisations in Africa during the 1984-6 food crisis. Most agencies have not yet fully evaluated the role of data in informing policy decisions during their respective emergency programmes. The case studies presented reflect a wide variety of approaches to targetting emergency food aid that are based largely on the use of 'socio-economic' data. The recent emergency relief operations in Africa seem to indicate a change in relief agencies' approaches to the assessment and monitoring of needs of the affected populations. Earlier dependance on nutritional data has given way to an increasing reliance on the use of socio-economic indicators. There was a wide variation in the case studies of the type of indicators collected and utilised in needs assessment and monitoring. There were those who relied almost exclusively on nutritional data to target resources during the 1984-86 African crisis, and others whose experiences during that period lead them to attach more weight to socio-economic data. Other agencies appear to have recognised the problems of relying solely on nutritional data to target food aid during their 1984–86 emergency programmes, and thus more or less abandoned classical anthropometric surveys in their needs assessment and monitoring methodologies during this period. Thus nutritional data has a less significant role in the decision making process than previously had been the case. 相似文献
18.
Riebsame WE 《Disasters》1985,9(4):295-300
Three recent cases of climate extremes are studied to identify human impacts and response strategies and to identify common characteristics that may help illuminate the nature of climate hazards. The 1980 heat wave in the central United States, 1981 cold wave in Boston, Massachusetts, and recent flooding and lake level rise in northern Utah, illustrate several important aspects of climate hazards that separate them from the more traditional set of catastrophic events (e.g. tornadoes, hurricanes and earthquakes) usually dealt with by hazards research and management. Among those characteristics are an emphasis on health impacts rather than physical damage, accumulative effects rather than short shocks, a tendency for impacts to accrue to certain socio-economic classes, and relatively slow onset. The management and research implications of these hazard characteristics are explored. 相似文献
19.
20.
Protein, lipid, phosphorus, and organic carbon contents, as well as electron transport system (ETS) activity, lactatedehydrogenase activity, and gut evacuation rate, were measured in four interzonal species of Pacific copepods:Calanus australis, C. pacificus, Eucalanus inermis, andE. elongatus f.hyalinus, collected at the upwelling areas off Peru (8°S) and California (27°N), and in the middle of the North Pacific (30°N), from February to April 1987. The two Eucalanidae species —E. inermis andE. elongatus — have distinctive biochemical and elemental body composition and rates of main physiological processes. Relative protein, lipid, phosphorus, and organic carbon contents (µg mg–1 wet weight) in these species were, respectively, ca. 1/7 to 1/10, 1/5 to 1/20, 1/5 to 1/10, and 1/5 those inCalanus spp. Likewise, oxygen uptake rate per unit of wet weight (based on ETS activity) inE. inermis andE. elongatus was 5 to 10% of that in calanids; a similar difference was found in phosphorus excretion rate. In addition, gut evacuation rates inE. inermis andE. elongatus were ca. one-fifth of those inCalanus spp. Based on these data, we considered the eucalanids as belonging to a distinctive physiological group, figuratively named jelly-body copepods. In contrast with calanids, active lactatedehydrogenase has been found in the bodies ofE. inermis andE. elongatus, apparently allowing them to survive for a long time in layers of extremely low oxygen content (<0.2 ml l–1). The adaptive value of physiological features in these eucalanids and typical calanids is compared. 相似文献