Changes in Plant Communities with Permafrost Thaw

Question 1

Plant functional traits

Answer 1

any morphological, physiological, or phenological feature measurable at the individual level, from the cell to the whole-organism level

Question 2

Global leaf economic spectrum

Answer 2

coordination of 6 leaf traits relating to plant productivity and carbon dynamics along a single axis

Question 3

6 leaf traits of the global leaf economic spectrum

Answer 3

maximum photosynthetic rate
dark respiration rate
specific leaf area
foliar nitrogen
foliar phosphorus
leaf longevity

Question 4

morphological features

Answer 4

leaf size, plant height

Question 5

physiological features

Answer 5

photosynthetic and respiration rates

Question 6

phenological features

Answer 6

day of flowering and bud burst

Question 7

resource conservation strategy

Answer 7

slow return on investment = large intial investment in tough, long-lived leaves with slow photosynthetic rate

Question 8

resource acquisitive strategy

Answer 8

fast return on investment = small intial investment in cheap, short-lived leaves with fast photosynthetic rate

Question 9

LMA ________ with increasing rainfall and annual temp

Answer 9

decreased

Question 10

intraspecifc trait variation

Answer 10

variation of plant functional traits within an individual species often as a result of changing environmental characteristics

Question 11

Arctic sites show…..

Answer 11

increases in shrubs and graminoids, abundance and decreases in lichen, and moss abundance with warming

Question 12

how much carbon does the boreal biome store

Answer 12

30-40%, mostly in the permafrost

Question 13

active layer thickness

Answer 13

area of soil that is not frozen and utilized by plants

Question 14

treed sites

Answer 14

lots of overlapping similarities between tree sites

Question 15

treeless sites

Answer 15

no overlap with treed sites. All were very similar to each other. Has greater ALT

Question 16

New N sources with permafrost thaw

Answer 16

plant avalible N from thawed soil
increased microbial mineralization of organic N from thawed soil and in active layer

Question 17

Ecosystem respiration

Answer 17

release of CO2

Question 18

Net ecosystem exchange

Answer 18

net flux of CO2

Question 19

gross primary productivity

Answer 19

uptake of CO2

Question 20

how do community-level traits and forest floor carbon fluxes respond to fertilization and does local variation in canopy cover influnece these responses?

Answer 20

vascular community-level traits greater with shallow fertilizatino only at low site; no site effect
moss community level traits differ between sites; no fertilization effect
greater ER with shallow and deep fertilization, only at low site; low site greater ER than high site