Problem: Two farmers are having a conversation at a bar about how their soil is doing. Jeff takes a sip of his beer and says that he just discovered that his soil is hypoxic. Brandon is trying to get the attention of the bartender so he can order another martini. Upon hearing Jeff's remark about his soil, Brandon states that the soil on his own farm is not hypoxic. Brandon is relieved when he notices the bartender is finally walking over to them. Given the paragraph above, please answer correctly the following question: Does Jeff's soil have more or less toxic compounds than Brandon's? Hint: When soil is flooded, hypoxia develops, as soil microorganisms consume oxygen faster than diffusion occurs. The presence of hypoxic soils is one of the defining characteristics of wetlands. Many wetland plants possess aerenchyma, and in some, such as water-lilies, there is mass flow of atmospheric air through leaves and rhizomes. There are many other chemical consequences of hypoxia. For example, nitrification is inhibited as low oxygen occurs and toxic compounds are formed, as anaerobic bacteria use nitrate, manganese, and sulfate as alternative electron acceptors. The reduction-oxidation potential of the rhizhosphere decreases and metal ions such as iron and manganese precipitate. Aerenchyma is a modification of the parenchyma.

A: more

Problem: Two villages were situated on different sides of the hill. Each village has its own approach to agriculture. East village decided to clear the land, by felling many trees and bushes, and set up a vast irrigation system. West village too a more natural approach to food production and applied the edible forest method, and all the permaculture principles over the years. Given the paragraph above, please answer correctly the following question: Which village had more problems with groundwater salinization? Hint: Groundwater salinization compromises buffering properties. Vegetation clearance, along with irrigation, causes serious issues. Irrigation increases the water table and mobilizes salts, and vegetation clearance allows it to come in contact with water habitats and vegetation. This stresses species not adapted to high salinity. High levels of salinity reduces water uptake in plants, by causing stomatal closure, reducing photosynthesis. Forests undergo decline in areas of high salinity and shallow groundwater depths because these conditions make them more susceptible to droughts. Forests undergo decline in areas of high salinity and shallow groundwater depths making them more susceptible to droughts.

A: East

Problem: Two farms used AM fungi for the plants. Brown farm also decided to grow cover crops on those parcels of land to help mycorrhizal growth. Orange farm didn't grow cover crops. Given the paragraph above, please answer correctly the following question: Which farm didn't provide extended time for AM fungi growth into the autumn? Hint: Since AM fungi are biotrophic, they are dependent on plants for the growth of their hyphal networks. Growing a cover crop extends the time for AM growth into the autumn, winter, and spring. Promotion of hyphal growth creates a more extensive hyphal network. The mycorrhizal colonization increase found in cover crops systems may be largely attributed to an increase in the extraradical hyphal network that can colonize the roots of the new crop (Boswell et al. 1998). The extraradical mycelia are able to survive the winter, providing rapid spring colonization and early season symbiosis (McGonigle and Miller 1999). This early symbiosis allows plants to tap into the well-established hyphal network and be supplied with adequate phosphorus nutrition during early growth, which greatly improves the crop yield.

A: Orange

Problem: Two countries from the same continent have very different climates. Icelandia, located at 70N latitude, and Uganda, situated just south of 30N, Icelandia was mostly flat, had a few mountains under 1,000 ft, but Uganda had a mountain range with peaks just under 3,000 ft. Given the paragraph above, please answer correctly the following question: Which country had larger regions of alpine tundra? Hint: Alpine tundra occurs at high enough altitude at any latitude. Portions of montane grasslands and shrublands ecoregions worldwide include alpine tundra. Large regions of alpine tundra occur in the North American Cordillera, the Alps and Pyrenees of Europe, the Himalaya and Karakoram of Asia, the Andes of South America, and the Eastern Rift mountains of Africa.Alpine tundra occupies high-mountain summits, slopes, and ridges above timberline. Aspect plays a role as well; the treeline often occurs at higher elevations on warmer equator-facing slopes. Because the alpine zone is present only on mountains, much of the landscape is rugged and broken, with rocky, snowcapped peaks, cliffs, and talus slopes, but also contains areas of gently rolling to almost flat topography.Averaging over many locations and local microclimates, the treeline rises 75 metres (245 ft) when moving 1 degree south from 70 to 50N, and 130 metres (430 ft) per degree from 50 to 30N. Between 30N and 20S, the treeline is roughly constant, between 3,500 and 4,000 metres (11,500 and 13,100 ft).

A:
Icelandia