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141.
Abstract Community-based monitoring (CBM) activities in Canada are increasing. A conceptual framework developed for and used to guide a pilot CBM project in 31 Canadian communities is evaluated. The framework provided the strategic direction necessary for successful implementation of the pilot and proved useful in the training of community coordinators hired for the project. Limitations of the framework include its inadequate attention to community diversity, its linearity, and insufficient expression of the adaptive and synergistic nature of its components. In order to support local sustainability, CBM appears to require an approach that is context-specific, iterative, and adaptive. Given these emergent characteristics, an enhanced conceptual framework for CBM in Canada is developed based on four dynamic themes: community mapping, participation assessment, capacity building, and information delivery. 相似文献
142.
Puerto Rican Parrots and Potential Limitations of the Metapopulation Approach to Species Conservation 总被引:1,自引:0,他引:1
143.
144.
J. B. Graham 《Marine Biology》1970,5(2):136-140
Mnierpes macrocephalus
(Günther) inhabits the steep, current-swept shores of the tropical east Pacific Ocean; it makes frequent terrestrial excursions. Laboratory and field studies were undertaken to assess the importance of these excursions in its ecology. Several morphological features, such as body shape, padded ventral surfaces, thickened fin rays and incised fin membranes are related to its capacity for terrestrial locomotion. Its body scalation reduces desiccation. M. macrocephalus can endure prolonged exposure to air, apparently by respiring aerially. Its eyes are highly adapted for terrestrial vision through the presence of flattened corneas. Terrestriality appears to play a significant part in the capacity of M. macrocephalus to orientate at the oscillating water surface where it resides. 相似文献
145.
J.B. Free Ingrid H. Williams R.J.F.H. Pinset A. Townshend M.S. Basi C.L. Graham 《Environment international》1983,9(1):9-12
The metal contents of pollen loads gathered by honeybees have been determined in areas with known concentrations of soil-borne heavy metals. The manganese, zinc, copper, and lead contents of the pollen loads reflected those of the environment, indicating that honeybee colonies might be used to sample areas. 相似文献
146.
M. Anwar H. Khan M. M. Nazmul Hoque S. Shamsul Alam M. J. Ashfol Graham Nickless Dudley E. Shallcross 《环境科学学报(英文版)》2011,23(1):60-64
Night-time OH levels have been determined for UK urban surface environments using two methods, the decay and steady state
approximation methods. Measurement data from the UK National Environmental Technology Centre archive for four urban sites
(Bristol, Harwell, London Eltham and Edinburgh) over the time period of 1996 to 2000 have been used in this study. Three reactive
alkenes, namely isoprene, 1,3-butadiene and trans-2-pentene were chosen for the calculation of OH levels by the decay method. Hourly
measurements of NO, NO2, O3, CO and 20 VOCs were used to determine night-time OH level using the steady state approximation
method. Our results showed that the night-time OH levels were in the range of 1 105–1 106 molecules/cm3 at these four urban sites in
the UK. The application of a t-test of these analyses indicated that except Bristol, there was no significant di erence between the OH
levels found from the decay and steady state approximation methods. Night-time levels of the OH radical appeared to peak in summer
and spring time tracking the night-time O3 levels which also passed through a maximum at this time. 相似文献
147.
Nicholas A. J. Graham 《Marine Biology》2007,153(2):119-127
Coral reefs are under threat due to climate-mediated coral mortality, which affects some reef coral genera more severely than
others. The impact this has on coral reef fish is receiving increasing attention, with one focal area assessing impacts on
fish that feed directly on live coral. It appears that the more specialised a species of corallivore, the more susceptible
it is to coral declines. However data are sparse for the Indian Ocean, and little is known about why some corals are preferentially
fed upon over others. Here I assess feeding specialisation in three species of coral feeding butterflyfish in the Chagos Archipelago,
central Indian Ocean, assess the food quality of the coral genera they target and document patterns of decline in the Seychelles
following a severe coral mortality event. Cheatodon trifascialis was the most specialised coral feeder, preferentially selecting for Acropora corals, however, when Acropora was scarce, individuals showed considerable feeding plasticity, particularly for the dominant Pocillopora corals. C. trifasciatus also preferentially fed on Acropora corals, but fed on a much more diverse suite of corals and also displayed some selectivity for Porites. C. auriga is a facultative corallivore and consumed ∼55% live coral, which lies within the wide range of coral dependence reported
for this species. C:N ratio analysis indicated Lobophyllia and Acropora have the highest food quality, with Pocillopora having the lowest, which conforms with diet selection of corallivores and helps explain preferential feeding. Obligate specialist
feeders displayed the greatest declines through coral mortality in the Seychelles with obligate generalists also declining
substantially, but facultative feeders showing little change. Clearly a greater understanding of the species most vulnerable
to disturbance, their habitat requirements and the functional roles they play will greatly assist biodiversity conservation
in a changing climate. 相似文献
148.
Physical and chemical properties study of the activated carbon made from sewage sludge 总被引:21,自引:0,他引:21
Preparation of activated carbon from sewage sludge is a promising way to produce a useful adsorbent for pollutants removal as well as to dispose of sewage sludge. The objective of this study was to investigate the physical and chemical properties of the activated carbon made from sewage sludge so as to give a basic understanding of its structure. The activated carbon was prepared by activating anaerobically digested sewage sludge with 5 M ZnCl2 and thereafter pyrolyzing it at 500 degrees C for 2 h under nitrogen atmosphere. The properties investigated in the present study included its surface area and pore size distribution, its elemental composition and ash content, its surface chemistry structure and its surface physical morphology. Furthermore, its adsorption capacities for aqueous phenol and carbontetrachloride were examined. The results indicated that the activated carbon made from sewage sludge had remarkable micropore and mesopore surface areas and notable adsorption capacities for phenol and carbon-tetrachloride. In comparison with commercial activated carbons, it displayed distinctive physical and chemical properties. 相似文献
149.
150.
In 1999, the entire population of tourism-dependent Baños, Ecuador, some 16,000 people, was evacuated in anticipation of a violent eruption of Mount Tungurahua. Subsequently, many areas in the risk zone experienced heavy ash falls, lahars, and landslides, although no cataclysmic events occurred. Many small rural communities were also evacuated. While these communities became impacted by the hazard, Baños avoided most direct effects. Conditions for all evacuees were grim, and their conditions compounded because Ecuador was simultaneously undergoing profound economic and political crises. Absent livelihood alternatives, community leaders from Baños organized a return to their town even though it remained under an evacuation order. An aggressive campaign brought tourists and more residents back and Baños revived economically; however, this was achieved at the cost of hazard awareness among both groups, tourists and residents, and public safety became compromised. 相似文献