Modern Context Effects of climate change on plant biodiversity

1 modern context

1.1 effects of co2

1.1.1 effects of temperature
1.1.2 effects of water
1.1.3 general effects

modern context

there significant current interest , research focus on phenomenon of recent anthropogenic climate changes, or global warming. focus on identifying current impacts of climate change on biodiversity, , predicting these effects future.

changing climatic variables relevant function , distribution of plants include increasing co2 concentrations, increasing global temperatures, altered precipitation patterns, , changes in pattern of ‘extreme’ weather events such cyclones, fires or storms. highly variable species distribution has resulted different models variable bioclimatic changes.

because individual plants , therefore species can function physiologically, , complete life cycles under specific environmental conditions (ideally within subset of these), changes climate have significant impacts on plants level of individual right through level of ecosystem or biome.

effects of co2

recent increases in atmospheric co2.

co2 concentrations have been steadily rising more 2 centuries. increases in atmospheric co2 concentration affect how plants photosynthesise, resulting in increases in plant water use efficiency, enhanced photosynthetic capacity , increased growth. increased co2 has been implicated in ‘vegetation thickening’ affects plant community structure , function. depending on environment, there differential responses elevated atmospheric co2 between major ‘functional types’ of plant, such c3 , c4 plants, or more or less woody species; has potential among other things alter competition between these groups. increased co2 can lead increased carbon : nitrogen ratios in leaves of plants or in other aspects of leaf chemistry, possibly changing herbivore nutrition.

effects of temperature

global annual surface temperature anomaly in 2005, relative 1951-1980 mean

increases in temperature raise rate of many physiological processes such photosynthesis in plants, upper limit. these increases in photosynthesis , other physiological processes driven increased rates of chemical reactions , doubling of enzymatic product conversion rates every 10 °c increase in temperature. extreme temperatures can harmful when beyond physiological limits of plant.

one common hypothesis among scientists warmer area is, higher plant diversity. hypothesis can observed in nature, higher plant biodiversity located @ latitudes (which correlates specific climate/temperature).

effects of water

precipitation trends in united states, period 1901-2005. in areas rainfall has increased in last century, while areas have dried.

as water supply critical plant growth, plays key role in determining distribution of plants. changes in precipitation predicted less consistent temperature , more variable between regions, predictions areas become wetter, , drier. can cause major change in ecosystems dependent on water supply.

general effects

environmental variables act not in isolation, in combination other pressures such habitat degradation, habitat loss, , introduction of exotic species can potentially invasive. suggested these other drivers of biodiversity change act in synergy climate change increase pressure on species survive.