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1.
Existing tourism-related climate information and evaluation are typically based on mean monthly conditions of air temperature
and precipitation and do not include thermal perception and other climate parameters relevant for tourists. Here, we quantify
climate based on the climate facets relevant to tourism (thermal, physical, aesthetical), and apply the results to the Climate-Tourism-Information-Scheme
(CTIS). This paper presents bioclimatic and tourism climatological conditions in the Hunter Region—one of Australia’s most
popular tourist destinations. In the Hunter Region, generally, temperatures below 15°C occur from April through October, temperatures
less than 25°C are expected throughout the whole year, while humidity sits around 50%. As expected, large differences between
air temperature and physiologically equivalent temperature (PET) were clearly identified. The widest differences were seen
in summer time rather than in the winter period. In addition, cold stress was observed less than 10% of the time in winter
while around 40–60% of heat stress was observed in summer time. This correlates with the highest numbers of international
visitors, who usually seek a warmer weather, at the beginning of summer time (November and December) and also to the number
of domestic visitors, who tend to seek cooler places for recreation and leisure, in late summer (January–March). It was concluded
that thermal bioclimate assessment such as PET and CTIS can be applied in the Hunter region, and that local governments and
the tourism industry should take an integrated approach to providing more relevant weather and climate information for both
domestic and international tourists in the near future. 相似文献
2.
Climate, climate change and tourism all interact. Part of the public discussion about climate change focusses on the tourism
sector, with direct and indirect impacts being of equally high relevance. Climate and tourism are closely linked. Thus, climate
is a very decisive factor in choices both of destination and of type of journey (active holidays, wellness, and city tours)
in the tourism sector. However, whether choices about destinations or types of trip will alter with climate change is difficult
to predict. Future climates can be simulated and projected, and the tendencies of climate parameters can be estimated using
global and regional climate models. In this paper, the focus is on climate change in the mountainous regions of southwest
Germany – the Black Forest. The Black Forest is one of the low mountain ranges where both winter and summer tourism are vulnerable
to climate change due to its southern location; the strongest climatic changes are expected in areas covering the south and
southwest of Germany. Moreover, as the choice of destination is highly dependent on good weather, a climatic assessment for
tourism is essential. Thus, the aim of this study was to estimate climatic changes in mountainous regions during summer, especially
for tourism and recreation. The assessment method was based on human-biometeorology as well as tourism-climatologic approaches.
Regional climate simulations based on the regional climate model REMO were used for tourism-related climatic analyses. Emission
scenarios A1B and B1 were considered for the time period 2021 to 2050, compared to the 30-year base period of 1971–2000, particularly
for the warm period of the year, defined here as the months of March–November. In this study, we quantified the frequency,
but not the means, of climate parameters. The study results show that global and regional warming is reflected in an increase
in annual mean air temperature, especially in autumn. Changes in the spring show a slight negative trend, which is in line
with the trend of a decrease in physiologically equivalent temperature as well as in thermal comfort conditions. Due to the
rising air temperature, heat stress as well as sultry conditions are projected to become more frequent, affecting human health
and recreation, especially at lower lying altitudes. The tops of the mountains and higher elevated areas still have the advantage
of offering comfortable climatic conditions. 相似文献
3.
Climate is a key resource for many types of tourism and as such can be measured and evaluated. An index approach is required
for this task because of the multifaceted nature of weather and the complex ways that weather variables come together to give
meaning to climate for tourism. Here we address the deficiencies of past indices by devising a theoretically sound and empirically
tested method that integrates the various facets of climate and weather into a single index called the Climate Index for Tourism
(CIT). CIT rates the climate resource for activities that are highly climate/weather sensitive, specifically, beach “sun,
sea and sand” (3S) holidays. CIT integrates thermal (T), aesthetic (A) and physical (P) facets of weather, which are combined
in a weather typology matrix to determine a climate satisfaction rating that ranges from very poor (1 = unacceptable) to very
good (7 = optimal). Parameter A refers to sky condition and P to rain or high wind. T is the body-atmosphere energy balance
that integrates the environmental and physiological thermal variables, such as solar heat load, heat loss by convection (wind)
and by evaporation (sweating), longwave radiation exchange and metabolic heat (activity level). Rather than use T as a net
energy (calorific) value, CIT requires that it be expressed as thermal sensation using the standard nine-point ASHRAE scale
(“very hot” to “very cold”). In this way, any of the several body-atmosphere energy balance schemes available may be used,
maximizing the flexibility of the index. A survey (N = 331) was used to validate the initial CIT. Respondents were asked to rate nine thermal states (T) with different sky conditions
(A). They were also asked to assess the impact of high winds or prolonged rain on the perceived quality of the overall weather
condition. The data was analysed statistically to complete the weather typology matrix, which covered every possible combination
of T, A and P. Conditions considered to be optimal (CIT class 6–7) for 3S tourism were those that were “slightly warm” with
clear skies or scattered cloud (≤25% cloud). Acceptable conditions (CIT = 4–5) fell within the thermal range “indifferent”
to “hot” even when the sky was overcast. Wind equal to or in excess of 6 m/s (22 km/h) or rain resulted in the CIT rating
dropping to 1 or 2 (unacceptable) and was thus an override of pleasant thermal conditions. Further cross-cultural research
is underway to examine whether climate preferences vary with different social and cultural tourist segments internationally. 相似文献
4.
Tourism climate and thermal comfort in Sun Moon Lake,Taiwan 总被引:1,自引:0,他引:1
Bioclimate conditions at Sun Moon Lake, one of Taiwan’s most popular tourist destinations, are presented. Existing tourism-related
climate is typically based on mean monthly conditions of air temperature and precipitation and excludes the thermal perception
of tourists. This study presents a relatively more detailed analysis of tourism climate by using a modified thermal comfort
range for both Taiwan and Western/Middle European conditions, presented by frequency analysis of 10-day intervals. Furthermore,
an integrated approach (climate tourism information scheme) is applied to present the frequencies of each facet under particular
criteria for each 10-day interval, generating a time-series of climate data with temporal resolution for tourists and tourism
authorities. 相似文献
5.
There is considerable interest in understanding how ectothermic animals may physiologically and behaviourally buffer the effects of climate warming. Much less consideration is being given to how organisms might adapt to non-climatic heat sources in ways that could confound predictions for responses of species and communities to climate warming. Although adaptation to non-climatic heat sources (solar and geothermal) seems likely in some marine species, climate warming predictions for marine ectotherms are largely based on adaptation to climatically relevant heat sources (air or surface sea water temperature). Here, we show that non-climatic solar heating underlies thermal resistance adaptation in a rocky–eulittoral-fringe snail. Comparisons of the maximum temperatures of the air, the snail''s body and the rock substratum with solar irradiance and physiological performance show that the highest body temperature is primarily controlled by solar heating and re-radiation, and that the snail''s upper lethal temperature exceeds the highest climatically relevant regional air temperature by approximately 22°C. Non-climatic thermal adaptation probably features widely among marine and terrestrial ectotherms and because it could enable species to tolerate climatic rises in air temperature, it deserves more consideration in general and for inclusion into climate warming models. 相似文献
6.
Strong topographic variation interacting with low stature alpine vegetation creates a multitude of micro-habitats poorly represented
by common 2 m above the ground meteorological measurements (weather station data). However, the extent to which the actual
habitat temperatures in alpine landscapes deviate from meteorological data at different spatial scales has rarely been quantified.
In this study, we assessed thermal surface and soil conditions across topographically rich alpine landscapes by thermal imagery
and miniature data loggers from regional (2-km2) to plot (1-m2) scale. The data were used to quantify the effects of spatial sampling resolution on current micro-habitat distributions
and habitat loss due to climate warming scenarios. Soil temperatures showed substantial variation among slopes (2–3 K) dependent
on slope exposure, within slopes (3–4 K) due to micro-topography and within 1-m2 plots (1 K) as a result of plant cover effects. A reduction of spatial sampling resolution from 1 × 1 m to 100 × 100 m leads
to an underestimation of current habitat diversity by 25% and predicts a six-times higher habitat loss in a 2-K warming scenario.
Our results demonstrate that weather station data are unable to reflect the complex thermal patterns of aerodynamically decoupled
alpine vegetation at the investigated scales. Thus, the use of interpolated weather station data to describe alpine life conditions
without considering the micro-topographically induced thermal mosaic might lead to misinterpretation and inaccurate prediction. 相似文献
7.
Caroline Brosy Ksenija Zaninovic Andreas Matzarakis 《International journal of biometeorology》2014,58(6):1369-1381
Tourism is one of the most important economic sectors in Croatia. The Adriatic coast is a popular travel destination for tourists, especially during the summer months. During their activities, tourists are affected by atmospheric conditions and therefore by weather and climate. Therefore, it is important to have reliable information about thermal conditions as well as their impacts on human beings. Here, the climate tourism potential of Croatia is presented and quantified on the basis of three selected stations in different climatic regions. The physiologically equivalent temperature is used for analysis as well as other climatic parameters relevant for tourism and recreation. The results already point to hot conditions for outdoor activities in summer during afternoons, especially along the coast but also for continental regions, resulting in a reduction of the climate tourism potential. In the future, this trend looks set to increase, possibly leading to a changing tourism sector in Croatia requiring adaptation and new strategies. 相似文献
8.
Norbert Solymosi Csaba Torma Anikó Kern Ákos Maróti-Agóts Zoltán Barcza László Könyves Olaf Berke Jenő Reiczigel 《International journal of biometeorology》2010,54(4):423-431
Global climate change can have serious direct effects on animal health and production through heat stress. In Hungary, the
number of heat stress days per year (YNHD), i.e., days when the temperature humidity index (THI) is above a specific comfort
threshold, has increased in recent years based on observed meteorological data. Between 1973 and 2008, the countrywide average
increase in YNHD was 4.1% per year. Climate scenarios based on regional climate models (RCM) were used to predict possible
changes in YNHD for the near future (2021–2050) relative to the reference period (1961–1990). This comparison shows that,
in Hungary, the 30-year mean of YNHD is expected to increase by between 1 and 27 days, depending on the RCM used. Half of
the scenarios investigated in this study predicted that, in large parts of Hungary, YNHD will increase by at least 1 week.
However, the increase observed in the past, and that predicted for the near future, is spatially heterogeneous, and areas
that currently have large cattle populations are expected to be affected more severely than other regions. 相似文献
9.
Evaluation of the thermal heat requirement of Brassica spp. across agro-ecological regions is required in order to understand the further effects of climate change. Spatio-temporal
changes in hydrothermal regimes are likely to affect the physiological growth pattern of the crop, which in turn will affect
economic yields and crop quality. Such information is helpful in developing crop simulation models to describe the differential
thermal regimes that prevail at different phenophases of the crop. Thus, the current lack of quantitative information on the
thermal heat requirement of Brassica crops under debranched microenvironments prompted the present study, which set out to examine the response of biophysical
parameters [leaf area index (LAI), dry biomass production, seed yield and oil content] to modified microenvironments. Following
2 years of field experiments on Typic Ustocrepts soils under semi-arid climatic conditions, it was concluded that the Brassica crop is significantly responsive to microenvironment modification. A highly significant and curvilinear relationship was
observed between LAI and dry biomass production with accumulated heat units, with thermal accumulation explaining ≥80% of
the variation in LAI and dry biomass production. It was further observed that the economic seed yield and oil content, which
are a function of the prevailing weather conditions, were significantly responsive to the heat units accumulated from sowing
to 50% physiological maturity. Linear regression analysis showed that growing degree days (GDD) could indicate 60–70% variation
in seed yield and oil content, probably because of the significant response to differential thermal microenvironments. The
present study illustrates the statistically strong and significant response of biophysical parameters of Brassica spp. to microenvironment modification in semi-arid regions of northern India. 相似文献
10.
Indoor climate and air quality 总被引:2,自引:0,他引:2
In industrialized countries about 90% of the time is spent indoors. The ambient parameters affecting indoor thermal comfort
are air temperature and humidity, air velocity, and radiant heat exchange within an enclosure. In assessing the thermal environment,
one needs to consider all ambient parameters, the insulating properties of the occupants’ clothing, and the activity level
of the occupants by means of heat balance models of the human body. Apart from thermal parameters, air quality (measured and
perceived) is also of importance for well-being and health in indoor environments. Pollutant levels are influenced by both
outdoor concentrations and by indoor emissions. Indoor levels can thus be lower (e.g. in the case of ozone and SO2) or higher (e.g. for CO2 and formaldehyde) than outdoor levels. Emissions from cooking play an important role, especially in developing countries.
The humidity of the ambient air has a wide range of effects on the energy and water balance of the body as well as on elasticity,
air quality perception, build-up of electrostatic charge and the formation or mould. However, its effect on the indoor climate
is often overestimated. While air-handling systems are commonly used for achieving comfortable indoor climates, their use
has also been linked to a variety of problems, some of which have received attention within the context of ”sick building
syndrome”.
Received: 27 October 1997 / Accepted 26 November 1997 相似文献
11.
Potential impacts to freshwater ecosystems caused by flow regime alteration under changing climate conditions in Taiwan 总被引:3,自引:0,他引:3
Jian-Ping Suen 《Hydrobiologia》2010,639(1):115-128
Observed increases in the Earth’s surface temperature bring with them associated changes in precipitation and atmospheric
moisture that consequentially alter river flow regimes. Climate-induced flow regime changes are examined using the Indicators
of Hydrologic Alteration. This article uses observed daily streamflow data to examine the flow regime alteration and how these
changes might potentially affect freshwater ecosystems. Flow data from 23 gauging stations throughout Taiwan show that the
annual extreme water conditions (1-, 3-, 7-, 30-, 90-day annual minima or maxima) have increased alteration compared to baseline
periods (1961–1990). Specifically, more severe flood and drought events occur in the period after 1991 than the period from
1961 to 1990. The frequency and duration of flood and drought events also show increased fluctuation. Flow regimes are currently
being altered by stressors that will continue into the foreseeable future and it is also happing elsewhere in the world. Aquatic
organisms not only need to defend themselves from anthropogenic damage to the river system, but also face the on-going threat
from climate change-induced thermal and flow regime alteration. This article raises this issue so that water resources managers
may identify precautionary measures that reduce the cumulative effects of both anthropogenic flow alteration and changing
climate conditions. 相似文献
12.
L. Mariani S. G. Parisi G. Cola O. Failla 《International journal of biometeorology》2012,56(6):1123-1134
Atmospheric variables play a fundamental role in driving man-managed ecosystems and more specifically in agro-ecosystems, determining the quantity and quality of crop production. On the other hand, climate variability can be seen as the superimposition of gradual and abrupt changes. This paper is focused on European surface air temperature in the period 1951–2010. Analysis of this dataset identified breakpoints that define two homogeneous sub-periods: 1951–1987 and 1988–2010. Thermal resources for crops were analyzed adopting a “normal heat hours” approach. Computation highlighted a general increase in thermal resources in the European continent for crop groups II and III (C3 and C4 plants adapted to high or moderate temperatures), while a decline of thermal resources for crop group I (cold adapted C3) was highlighted in the Mediterranean area. The climate variability justifies a change in the potential latitudinal limits of different groups of crops, representing a fundamental step for crop adaptation to climate change. 相似文献
13.
Jessica Bergmann Sven Pompe Ralf Ohlemüller Martin Freiberg Stefan Klotz Ingolf Kühn 《Plant Ecology》2010,207(2):191-201
The application of niche-based modelling techniques to plant species has not been explored for the majority of taxa in Europe,
primarily due to the lack of adequate distributional data. However, it is of crucial importance for conservation adaptation
decisions to assess and quantify the likely pool of species capable of colonising a particular region under altered future
climate conditions. We here present a novel method that combines the species pool concept and information about shifts in
analogous multidimensional climate space. This allows us to identify regions in Europe with a current climate which is similar
to that projected for future time periods in Germany. We compared the extent and spatial location of climatically analogous
European regions for three projected greenhouse gas emission scenarios in Germany for the time period 2071–2080 (+2.4°C, +3.3°C,
+4.5°C average increase in mean annual temperature) to those of the recent past in Europe (1961–90). Across all three scenarios,
European land areas which are characterised by climatic conditions analogue to those found in Germany decreased from 14% in
1961–1990 to ca. 10% in 2071–2080. All scenarios show disappearing current climate types in Germany, which can mainly be explained
with a general northwards shift of climatically analogous regions. We estimated the size of the potential species pool of
these analogous regions using floristic inventory data for the Iberian Peninsula as 2,354 plant species. The identified species
pool in Germany indicates a change towards warmth and drought adapted southern species. About one-third of the species from
the Iberian analogous regions are currently already present in Germany. Depending on the scenario used, 1,372 (+2.4°C average
change of mean annual temperature), 1,399 (+3.3°C) and 1,444 (+4.5°C) species currently not found in Germany, occur in Iberian
regions which are climatically analogous to German 2071–80 climate types. We believe that our study presents a useful approach
to illustrate and quantify the potential size and spatial distribution of a pool of species potentially colonising new areas
under changing climatic conditions. 相似文献
14.
Jinmei Xu Jianxiong Lu Fucheng Bao Robert Evans Geoffrey Downes Rongfeng Huang Youke Zhao 《Trees - Structure and Function》2012,26(3):1007-1016
Microfibril angle (MFA) is an important factor in determining the mechanical properties of individual cells and wood as a
whole. While some studies have described the variation of MFA within trees, little work has been done on the extent to which
MFA is influenced by climate, despite it being known to respond to climatic events. Year-to-year variation in MFA and ring
width was measured at high resolution by SilviScan-3? on 30 dated Picea
crassifolia trees growing in the northeastern Tibetan plateau. The climate signals registered in MFA and ring width were analyzed using
dendroclimatological methods. The response function of MFA accounted for 67% of total variance, of which 60% was explained
by climate elements. The response function of ring width explained 57% total variance, 37% of which was explained by climate
variables. MFA significantly responded to July–August temperatures, and to precipitation in March, May and September. Over
the period 1987–2009 temperatures generally increase and appeared to have a greater influence on MFA. A decrease in the strength
of the relationship between MFA and ring width over the period 1987–2009 was also observed. MFA offers the potential to build
robust climate proxies. The strong climate sensitivity of MFA to increasing temperature or the observed changes in the MFA–ring
width relationship may contribute to resolving the “divergence problem” in temperature reconstructions. As far as we are aware,
this study is the first to show a strong climate response in MFA and suggests that it might be a useful climate proxy. 相似文献
15.
旅游与气候变化研究进展 总被引:3,自引:0,他引:3
旅游与气候变化研究已形成一个不断进化的知识领域。以Web of Science为数据源,应用信息可视化软件citespaceⅢ绘制旅游与气候变化研究领域的知识图谱,对该领域的研究前沿与知识基础、研究热点与发展趋势、研究力量与社会网络结构进行系统分析。结果表明:(1)旅游与气候变化研究正沿着"影响—适应—减缓"的路径演化,从单一问题研究向多维综合研究发展,旅游业碳排放始终是研究的核心问题;(2)12篇论文在旅游与气候变化知识网络演进中起到关键作用;(3)旅游与气候变化研究涉及多个学科,研究力量主要分布于欧洲、北美、大洋洲、东亚地区,欧洲的国家和地区之间有着较为密切的合作关系;(4)旅游与气候变化研究人员之间存在多个研究小组,已初步形成核心-边缘型社会网络结构,但研究机构之间仅存在少量合作关系,规模化的合作网络尚未形成。 相似文献
16.
Spatial and age-dependent tree-ring growth responses of Larix gmelinii to climate in northeastern China 总被引:2,自引:0,他引:2
Tree-ring width chronologies from 276 Larix gmelinii cores taken in northeastern China were used to analyze spatial and age-dependent growth–climate response relationships. Tree
radial growth from five localities showed similar patterns, while exhibiting different tree-ring growth responses to local
climate. The rotated principal component analysis (RPCA) indicated that tree age, growing season moisture conditions, and
ambient air temperature variations resulted from location differences (e.g., longitude, latitude, and altitude), which could
explain the non-stationary spatial climate–growth relations observed. The study tested the fundamental assumption that the
climate–growth of L. gmelinii was age independent after the removal of size trends and disturbance signals. The age-related climate–growth relationship
might potentially improve the veracity of past climate reconstructions. Bootstrapped correlation function analyses suggested
that the response of L. gmelinii radial growth to climate differed between trees ≥150 years old and <150 years old. Mean sensitivity and standard deviation
for trees increased with age in the <150 years old tree class; whereas trees ≥150 years old had no significant relationship
with age. These results showed that the assumption of age-independent climate–growth relationship is invalid at these sites.
Physiological processes and/or hydraulic constraints dependent on tree age, together with detrending techniques could be the
possible causal factors of clear age-dependent responses. These results suggested the importance of incorporating trees of
all ages into the chronology to recover a detailed climatic signal in a reconstruction of L. gmelinii for this region. 相似文献
17.
Wind is one of the main factors affecting people's outdoor thermal sensation. Ongoing urbanization and urban densification are transforming the urban climate and complicating the pedestrian-level wind environment. Therefore, the main aim of this research is to evaluate the potential wind-cooling effect on human outdoor thermal conditions. Accordingly, the current research attempts determine the best wind directions for thermal comfort at the studied stations and how these factors will be changed under the effects of global warming. Outdoor thermal conditions were modeled based on the physiologically equivalent temperature (PET) thermal index using RayMan software for the decades of the 2000s and the 2040s in different climate types of Iran (Csb, BWh, Csa, and BSh) To estimate the potential cooling effect of wind, the PET was calculated (1) under actual wind conditions, and (2) under calm wind (0.05 m/s) conditions. Then, the ΔPET for these two conditions, which indicates the cooling potential effect (CPE) of the wind, was calculated for four representative stations (Ardebil, Bandar Abbas, Gorgan, and Shiraz). In comparison with the 2000s, the results indicated that by the 2040s, the predicted wind cooling potential will have increased in Ardebil, Shiraz, Bandar Abbas and Gorgan (CPE of 13.2 °C, 13.1 °C, 11.2 °C, and 11 °C, respectively). Based on the overall average of two climate change scenarios (A2 and B1) used in this study, the occurrence of “comfortable” conditions by the 2040s will have increased in Bandar Abbas, Shiraz, and Ardebil by 1.1%, 0.4%, and 0.3%, respectively, while it will have decreased in Gorgan by 1.5%. Accounting for the cooling effect of wind, the comfort cooling potential of wind is predicted to rise by an average of 1.6 °C in the 2040s compared with the 2000s in all the studied stations. Therefore, this will affect the microclimates positively and could reduce the urban heat island effects. 相似文献
18.
Ecological effects of longline fishing and climate change on the pelagic ecosystem off eastern Australia 总被引:1,自引:0,他引:1
Shane P. Griffiths Jock W. Young Matt J. Lansdell Robert A. Campbell John Hampton Simon D. Hoyle Adam Langley Donald Bromhead Michael G. Hinton 《Reviews in Fish Biology and Fisheries》2010,20(2):239-272
Pelagic longline fisheries target (or catch incidently) large apex predators in the open ocean (e.g. tunas, billfish and sharks)
and have the potential to disrupt the ecosystem functionality if these predators exert strong top–down control. In contrast,
warming of oceans from climate change may increase bottom–up effects from increases in primary productivity. An ecosystem
model of a large pelagic ecosystem off eastern Australia was constructed to explore the potential ecological effects of climate
change and longlining by Australia’s Eastern Tuna and Billfish Fishery. The model reproduced historic biomass and fishery
catch trends from 1952 to 2006 for seven functional groups. Simulated changes in fishing effort and fishing mortality rate
on individual target species from 2008 to 2018 resulted in only modest (<20%) changes in the biomass of target species and
their direct predators or competitors. A simulated increase in phytoplankton biomass due to climate change resulted in only
small increases (<11%) in the biomass of all groups. However, climate-related changes to the biomass of micronekton fish (−20%)
and cephalopods (+50%) resulted in trophic cascades. Our results suggest there may be ecological redundancy among high trophic
level predators since they share a diverse suite of prey and collectively only represent <1% of the total system biomass.
In contrast, micronekton fishes and cephalopods have high biomasses and high production and consumption rates and are important
as both prey and predators. They appear to exert ‘wasp–waist’ control of the ecosystem rather than top–down or bottom–up processes
reported to drive other pelagic systems. 相似文献
19.
Ashley D. Ficke Christopher A. Myrick Lara J. Hansen 《Reviews in Fish Biology and Fisheries》2007,17(4):581-613
Despite uncertainty in all levels of analysis, recent and long-term changes in our climate point to the distinct possibility
that greenhouse gas emissions have altered mean annual temperatures, precipitation and weather patterns. Modeling efforts
that use doubled atmospheric CO2 scenarios predict a 1–7°C mean global temperature increase, regional changes in precipitation patterns and storm tracks,
and the possibility of “surprises” or sudden irreversible regime shifts. The general effects of climate change on freshwater
systems will likely be increased water temperatures, decreased dissolved oxygen levels, and the increased toxicity of pollutants.
In lotic systems, altered hydrologic regimes and increased groundwater temperatures could affect the quality of fish habitat.
In lentic systems, eutrophication may be exacerbated or offset, and stratification will likely become more pronounced and
stronger. This could alter food webs and change habitat availability and quality. Fish physiology is inextricably linked to
temperature, and fish have evolved to cope with specific hydrologic regimes and habitat niches. Therefore, their physiology
and life histories will be affected by alterations induced by climate change. Fish communities may change as range shifts
will likely occur on a species level, not a community level; this will add novel biotic pressures to aquatic communities.
Genetic change is also possible and is the only biological option for fish that are unable to migrate or acclimate. Endemic
species, species in fragmented habitats, or those in east–west oriented systems will be less able to follow changing thermal
isolines over time. Artisanal, commercial, and recreational fisheries worldwide depend upon freshwater fishes. Impacted fisheries
may make it difficult for developing countries to meet their food demand, and developed countries may experience economic
losses. As it strengthens over time, global climate change will become a more powerful stressor for fish living in natural
or artificial systems. Furthermore, human response to climate change (e.g., increased water diversion) will exacerbate its
already-detrimental effects.
Model predictions indicate that global climate change will continue even if greenhouse gas emissions decrease or cease. Therefore,
proactive management strategies such as removing other stressors from natural systems will be necessary to sustain our freshwater
fisheries. 相似文献
20.
The Toronto–Windsor corridor of Southern Ontario, Canada, experiences hot and humid weather conditions in summer, thus exposing
the population to heat stress and a greater risk of mortality. In the event of a climate change, heat-stress conditions may
become more frequent and severe in Southern Ontario. To assess the impact of summer weather on health, we analyzed heat-related
mortality in the elderly (older than 64 years) in the metropolitan areas of Windsor, London, Kitchener-Waterloo-Cambridge,
Hamilton, and Toronto for a 17-year period. Demographic, socioeconomic, and housing factors were also evaluated to assess
their effect on the potential of the population to adapt and their vulnerability to heat stress. Heat-stress days were defined
as those with an apparent temperature (heat index) above 32°C. Mortality among the elderly was significantly higher on heat-stress
days than on non-heat-stress days in all cities except Windsor. The strongest relationships occurred in Toronto and London,
followed by Hamilton. Cities with the greatest heat-related mortality have relatively high levels of urbanization and high
costs of living. Even without the warming induced by a climate change, (1) vulnerability is likely to increase as the population
ages, and (2) ongoing urban development and sprawl are expected to intensify heat-stress conditions in Southern Ontario. Actions
should be taken to reduce vulnerability to heat stress conditions, and to develop a comprehensive hot weather watch/warning
system for the region.
Received: 9 August 1999 / Revised: 9 March 2000 / Accepted: 1 May 2000 相似文献