[Q]: The benefits provided by no-tillage to predators may lead to larger predator populations, which is a good way to control pests (biological control), but also can facilitate predation of the crop itself. In corn crops, for instance, predation by caterpillars can be higher in no-till than in conventional tillage fields.In places with rigorous winter, untilled soil can take longer to warm and dry in spring, which may delay planting to less ideal dates. Another factor to be considered is that organic residue from the prior year's crops lying on the surface of untilled fields can provide a favorable environment to pathogens, helping to increase the risk of transmitting diseases to the future crop. And because no-till farming provides good environment for pathogens, insects and weeds, it can lead farmers to a more intensive use of chemicals for pest control. Other disadvantages of no-till include underground rot, low soil temperatures and high moisture.Based on the balance of these factors, and because each farm has different problems, agroecologists will not attest that only no-till or complete tillage is the right way of farming. Yet, these are not the only possible choices regarding soil preparation, since there are intermediate practices such as strip-till, mulch-till and ridge-till, all of them just as no-till categorized as conservation tillage. Agroecologists, then, will evaluate the need of different practices for the contexts in which each farm is inserted. Two farmers, Tom and Brad, applied different farming methods. Tom tilled his land, while Brad applied the no-till gardening method. Which farmer had a soil that took longer to dry in spring?
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[A]: Brad

[Q]: An anaerobic organism is any organism that does not need oxygen for growth and even dies in its presence. Obligate anaerobes will die when exposed to atmospheric levels of oxygen. Clostridium perfringens bacteria, which are commonly found in soil around the world, are obligate anaerobes. Infection of a wound by C. perfringens bacteria causes the disease gas gangrene. Obligate anaerobes use molecules other than oxygen as terminal electron acceptors. Microbiologist John is studying the anaerobic organism. He collected two samples of this organism, sample A and sample B. Sample A is an anaerobic organism, and sample B is specifically identified as the Clostridium perfringens obligate anaerobe. To compare these samples to other organisms he collected another microbe that is not an anaerobic organism. He labeled it as sample C. Which sample would need oxygen for growth, sample A or sample C?
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[A]: sample C

[Q]: 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. John is a soil scientist. He has been studying the lands near Mississippi delta. He noticed cases of hypoxia in that are. He labeled that study as case A. To compare that to other areas he visited Arizona. There he didn't see any occurrence of hypoxia. He labeled that case as case B. Would case A see less or more oxygen in the soil due to microorganism activities than case B?
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[A]: less

[Q]: When humans dig up and use fossil fuels, we have an impact on the carbon cycle ( Figure below ). This carbon is not recycled until it is used by humans. The burning of fossil fuels releases more carbon dioxide into the atmosphere than is used by photosynthesis. So, there is more carbon dioxide entering the atmosphere than is coming out of it. Carbon dioxide is known as a greenhouse gas , since it lets in light energy but does not let heat escape, much like the panes of a greenhouse. The increase of greenhouse gasses in the atmosphere is contributing to a global rise in Earth's temperature, known as global warming or global climate change. Two different countries produced their electricity using different methods. Burma used fossil fuels such as coal and oil, while Bhutan used renewable energy sources. Which country contributed less to a global rise in Earth's temperature?
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[A]:
Bhutan