100 Species - Pine Spruce O Fir Pine - Spruce Fir 80- 60- - 40 20 - 10 15 Period of decomposition (years) 20 25 30 Mass Remaining (%) H HH

Figure 21.6 The Svalbard seed vault is located on Spitsbergen island in Norway, which has an arctic climate. Why might an arctic climate be good for seed Storage?

Figure 47.6 Scientists measured the relative abundance ot fern spores above and below the K-Pg boundary in this reck sample. Which of the following statements most likely represents their findings? An abundance of fern spores from several species was found below the K-Pg boundary, but none was found above. An abundance of fern spores from several species was found above the K-Pg boundary, but none was found below. An abundance of fern spores was found both above and below the K-Pg boundary, but only one species was found below the boundary , and many species were found above the boundary. Many species of fern spores were found both above and below the boundary, but the total number of spores was greater below the boundary.

The nutrition of some plants is enhanced by a mutually beneficial association between a root and a fungus. The association is known as _________. a. root nodule c. root hair b. mycorrhiza d. hypha

Why do mosses grow well in the Arctic tundra? a. They grow better at cold temperatures. b. They do not require moisture. c. They do not have true roots and can grow on hard surfaces. d. There are no herbivores in the tundra.

Tree Rings Reveal Droughts El Malpais National Monument, in west central New Mexico, has pockets of vegetation that have been surrounded by lava fields for about 3,000 years, so they have escaped wildfires, grazing animals, agricultural activity, and logging. Henri Grissino-Mayer generated a 2,129-year annual precipitation record using tree ring data from living and dead trees in this park (FIGURE 27.22). FIGURE 27.22 Annual precipitation record for 2,129 years, inferred from compiled tree ring data in El Malpais National Monument, New Mexico. Data were averaged over 10-year intervals; the graph correlates with other indicators of rainfall collected in all parts of North America. PDSI, Palmer Drought Severity Index: 0, normal rainfall; increasing numbers mean increasing excess of rainfall; decreasing numbers mean increasing severity of drought. A severe drougt contributed to a series of catastrophic dust storms that turned the midwestern United States into a "dust bowl" between 1933 and 1939. One of the worst population catastrophes ever recorded occurred in Mesoamerica between 1519 and a.d. 1600, when around 22 million people native to the region died. Which period between 137 b.c. and 1992 had the most severe drought? How long did that drought last?

Plants are a source of food fuel medicine all of the above

How would loss of fungi in a forest effect biogeochemical cycles in the area? Nitrogen could no longer be fixed into organic molecules Phosphorus stores would be released for use by other organisms Sulfur release from eroding rocks would cease Carbon would accumulate in dead organic matter and waste.