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Hawaii’s game animals are all non-native species, which provokes human–wildlife conflict among stakeholders. The management of human–wildlife conflict in Hawaii is further complicated by the discrete nature of island communities. Our goal was to understand the desires and perceived values or impacts of game held by residents of Hawaii regarding six game species [pigs (Sus scrofa), goats (Capra hircus), mouflon (Ovis musimon), axis deer (Axis axis), turkeys (Melagris gallopavo), and doves (Geopelia striata)]. We measured the desired abundance of game on the six main Hawaiian Islands using the potential for conflict index and identified explanatory variables for those desires via recursive partitioning. In 2011 we surveyed 5,407 residents (2,360 random residents and 3,047 pre-identified stakeholders). Overall 54.5 and 27.6 % of the emailed and mailed surveys were returned (n = 1,510). A non-respondent survey revealed that respondents and non-respondents had similar interest in wildlife, and a similar education level. The desired abundance of game differed significantly among stakeholders, species, and islands. The desired abundance scores were higher for axis deer, mouflon, and turkeys compared to pigs, goats or doves. Enjoyment at seeing game and the cultural value of game were widespread explanatory variables for desired abundance. Models for Lanai emphasized the economic value of game, whereas models for Maui identified the potential for game to contaminate soil and water. Models for Oahu and Kauai revealed concern for human health and safety. Given our findings we recommend managers design separate management plans for each island taking into consideration the values of residents. 相似文献
23.
Carlos Neira Edwin D Grosholz Lisa A Levin Rachael Blake 《Ecological applications》2006,16(4):1391-1404
Many coastal habitats are being substantially altered by introduced plants. In San Francisco Bay, California, USA, a hybrid form of the eastern cordgrass Spartina alterniflora is rapidly invading open mudflats in southern and central sections of the Bay, altering habitat, reducing macrofaunal densities, and shifting species composition. The invasion has resulted in significant losses of surface-feeding amphipods, bivalves, and cirratulid polychaetes, while subsurface feeding groups such as tubificid oligochaetes and capitellid polychaetes have been unaffected. In the present paper, we document the causes and mechanisms underlying the changes observed. Through a series of in situ manipulative experiments we examined the influence of hybrid Spartina canopy on a range of physical, chemical, and biological properties. The hybrid Spartina canopy exerted a strong influence on the hydrodynamic regime, triggering a series of physical, chemical, and biological changes in the benthic system. Relative to tidal flats, water velocity was reduced in hybrid patches, promoting deposition of fine-grained, organic-rich particles. The resulting changes in the sediment environment included increased porewater sulfide concentrations and anoxia, which led to poor survivorship of surface feeders such as bivalves, amphipods, and polychaetes. These are key taxa that support higher trophic levels including migratory shorebirds that feed on tidal flats. Altered flow in the Spartina canopy further contributed to changes in barnacle recruitment and resuspension of adult benthic invertebrates. Increased crab-induced predation pressure associated with Spartina invasion also contributed to changes in benthic invertebrate communities. Our results suggest that multiple physical, chemical, biotic, and trophic impacts of the Spartina invasion have resulted in substantial changes in benthic communities that are likely to have important effects on the entire ecosystem. 相似文献
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25.
Zhao Y Mann MD Olson ES Pavlish JH Dunham GE 《Journal of the Air & Waste Management Association (1995)》2006,56(5):628-635
This paper is particularly related to elemental mercury (Hg0) oxidation and divalent mercury (Hg2+) reduction under simulated flue gas conditions in the presence of nitric oxide (NO) and sulfur dioxide (SO2). As a powerful oxidant and chlorinating reagent, Cl2 has the potential for Hg oxidation. However, the detailed mechanism for the interactions, especially among chlorine (Cl)-containing species, SO2, NO, as well as H2O, remains ambiguous. Research described in this paper therefore focused on the impacts of SO2 and NO on Hg0 oxidation and Hg2+ reduction with the intent of unraveling unrecognized interactions among Cl species, SO2, and NO most importantly in the presence of H2O. The experimental results demonstrated that SO2 and NO had pronounced inhibitory effects on Hg0 oxidation at high temperatures when H2O was also present in the gas blend. Such a demonstration was further confirmed by the reduction of Hg2+ back into its elemental form. Data revealed that SO2 and NO were capable of promoting homogeneous reduction of Hg2+ to Hg0 with H2O being present. However, the above inhibition or promotion disappeared under homogeneous conditions when H2O was removed from the gas blend. 相似文献
26.
Studies were conducted to evaluate the changes of phosphorus in marine water and sediments of seven stations in the coastal areas off Cochin. Samples were collected on a monthly basis from January 2001 to December 2001. Results revealed higher levels of P in marine water samples collected during October-December 2001. The marine water P ranged from 0 to 0.38 ppm throughout the year. Speciation of P in marine sediment revealed that the Al bound P was maximum compared to Fe, Ca and organic bound P. Loosely bound and aluminium bound P was maximum during October-December especially in 10 and 20 m depth stations off Narakkal. Fe bound P was found to be least in June and September and highest during January-April. Low levels of Ca bound P were detected in samples collected during January-March and inorganic P was maximum in June and September. Organic bound P was maximum in 10 m depth stations and also during June and September. Phosphate fractions varied with locations and exhibited seasonal fluctuations. 相似文献
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28.
Summary The distinguishing characteristics of secondary metabolism and its associated metabolites are outlined. Current theories relating to the function of secondary metabolism in plants and micro-organisms are enumerated and the view that consideration of the processes rather than the products may best explain the origins of secondary metabolism is discussed. 相似文献
29.
The sintering process is among the major sources of the very toxic polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in the environment. At the industrial scale, it has been shown that dust collected on the grid, which supports the feed, contains PCDD/Fs amounts between the values found in the bottom of the cake and the values found on dust collected during gas sampling in the wind boxes. This fact suggests that the grid, containing 25wt.% of chromium, could have a catalytic activity in PCDD/Fs formation during the sintering process. This research tries to study this potential role. The de novo synthesis of PCDD/Fs is simulated at laboratory scale by thermal treatments of samples mixed with grid filings or Cr2O3. The thermal experiments performed with E.S.P. dust (dust collected in the electrostatic precipitator of a sintering plant) or graphite mixed with grid filings do not allow to confirm a role of the grid in PCDD/Fs formation during the industrial process. On the other hand, it has been shown that Cr2O3 can be considered as a catalyst in the de novo synthesis of PCDD/Fs. This compound takes place in the two steps of the de novo synthesis: the degradation of the carbon matrix as well as the chlorination reactions. 相似文献
30.
Llano-Sotelo JM Alcaraz-Melendez L Castellanos Villegas AE 《Journal of environmental biology / Academy of Environmental Biology, India》2010,31(4):497-502
In order to evaluate their responses to drought, we determined the photosynthetic activity water potential, stomatal conductance, transpiration, water use efficiency photosynthetic photon flux density and leaf temperature of Paulownia imperialis, P. fortunei and P. elongata in three different soil moisture conditions in the field. Our results showed that P. imperialis had greater photosynthesis (8.86 micromol CO2 m(-2) s(-1)) and instantaneous water use efficiency (0.79 micromol CO2 mmol H2O(-1)) than either P. elongata (8.20 micromol CO2 m(-2) s(-1) and 0.71 micromol CO2 mmol H2O(-1)) or P. fortunei (3.26 micromol CO2 m(-2) s(-1) and 0.07 micromol CO2 mmol H2O(-1)). The rapid growth of Paulownia did not appear to be correlated with photosynthetic rates. Paulownia fortunei showed more transpiration (48.78 mmol H2O m(-2) s(-1)) and stomatal conductance (840 mmol m(-2) s(-1)) than P. imperialis (20 mmol H2O m(-2) s(-1) and 540 mmol m(-2) s(-1)) and P. elongata (20 mmol H2O m(-2) s(-1) and 410 mmol m(-2) s(-1)), which allowed these two Paulownia species to increase their tolerance to low soil moisture, and maintain higher water use efficiency under these conditions. According to our physiological gas exchange field tests, Paulownia imperialis does appear to be capable of successful growth in semiarid zones. 相似文献