9.4 community change in space and time

Question 1

what is the nature of communities?

Answer 1

the changing nature of community structure across the landscape reflects the shifting distribution of populations in response to:
-changing environmental conditions
-interactions among species
-community structure is dynamic
-shifting pattern of species’ dominance and diversity through time

community the structure varies in time and space
-across the landscape (zonation)

Question 2

what is the nature of communities of patches?

Answer 2

-patches making up the landscape mosaic result from the interactions of factors: geology, topography, soils and climate
-environmental gradients are thus key in dictating local biodiversity and species composition

Question 3

Question 4

Question 5

what are transition zones?

Answer 5

-borders blend elements from all adjacent patches and offer unique habitats with relatively easy access to adjacent communities
-the edge effect in the phenomenon where edge communities are often quite diverse

Question 6

what are edge species (edge species)?

Answer 6

are those restricted exclusively to the edge environment
-for example, indigo bunting (bird species)

Question 7

what are edge effects?

Answer 7

Question 8

what are patch traits of larger habitat patches?

Answer 8

-larger habitat patches contain a greater number of individuals (population size) and species (species richness) than do small patches
-the increase in population size is a function of the increasing carrying capacity for the species
-more area=more home ranges and territories

Question 9

what are patch traits?

Answer 9

-larger patches are more likely to contain variations in topography and soils
-greater diversity of plant life=a wider array of habitats for animal species
-patch size and shape effect the relative abundance of edge and interior environments
-only a larger patch can develop interior conditions

Question 10

Answer 10

Question 11

what is the species-area relationship?

Answer 11

Question 12

what is fragmentation and patch trails?

Answer 12

-patches making up the landscape mosaic results from the interactions of factors: geology, topography, soils and climate
-human activity makes its mark on the broad-sale distribution of communities
-fragmentation of the natural landscape into isolated patches of forest, grassland and shrubland

Question 13

what are examples of fragmentation?

Answer 13

Question 14

how do species react to fragmentation?

Answer 14

species do not do well with fragmentation
-area-sensitive species often lost first
-extensive habitat loss lowers diversity and changes community composition

Question 15

Answer 15

species sensitivity to fragmentation

Question 16

what are the effects of fragmentation?

Answer 16

-indirect effects of habitat fragmentation

for example, in north america prairies brrod parasitism has increase
-brown headed cowbird
-the percentage of yellow warbler nests parasitized by cowbirds increases with the percent of land fragmented by human population

Question 17

what are some species that do well with fragmentation?

Answer 17

-small, habitat generalist and fast-reproducing mammals and birds that do well in grasslands and shrublands, or lands, converted to agriculture
-in boreal plains and rocky mountain foothills

Question 18

what are the methods of feral horses and predator interactions?

Answer 18

-spatially explicit capture-recapture grid of trail cameras
-identify horses using individual markings
-single-season occupancy compared across species

Question 19

Answer 19

Question 20

what is succession?

Answer 20

community structure varies in time and space
-across the landscape (zonation)
-in one position as time passes

succession is the gradual and (seemingly) directional change in community structure through time