Land Management And Minerals Unit 5: The Geosphere

Different Categories As our population grows, more resources from rural lands are needed to support the population Land can be broken down into… Farmland Rangeland Forest land Parks and Preserves The Wilderness Regardless of how we managed the land (good or bad), it is essential for those ecosystem services.

Farmland Used to grow crops and fruit The U.S. once contained more than 100 million hectares Threatened by urban development 1996 – Farmland Protection Program Think back to agricultural ethics!

Rangeland Supports different types of vegetation; not used for farming Commonly used to feed livestock Most damage comes from overgrazing (too many animals)—changes the plant community (invasives!) 1978 – Public Rangelands Improvement Act was enacted to improve land management practices Leaving it alone Reducing herd size Planting native species; killing invasive ones Spreading out water holes But also native species! (benefit off of this) Both this and farmland are essential for maintaining the world’s food supply

Forest Land We use timber products everyday: wood and paper; but also maple syrup and turpentine (making paints)! Three categories: virgin (never been cut), native (but managed), and tree farms (planted in rows; cut down) Harvesting trees Clear-cutting – removing all trees from an area (bad for wildlife and causes soil erosion) Selective cutting – cutting and removing middle-aged trees To get what we need: equivalent to each person cutting down a tree that is 30 meters tall each year You can imagine the cost/benefit Tree farms help with fragmentation!

Problems (and Solutions) in Forestlands Deforestation (habitat fragmentation) Can result in soil erosion if not covered (cover crops) Reforestation – NE contains more forest land that it did in 1900! Government or Private tree plantings Story of New York – state bought lands during Great Depression and fixed them! NE = New England

Parks, Preserves, and Wilderness 1870 – individuals from Montana/Wyoming brought land use concerns to Congress which led to… UN Man and the Biosphere Program – include people! U.S. Wilderness Act – designates certain areas Wilderness – the land and ecosystems it supports are protected from all exploitation Yellowstone

Minerals – What Are THEY? Can be 1 element or 2 or more bonded together (a compound) Naturally occurring Inorganic (usually) – no carbon Orderly internal structure (lattice) Set chemical and physical properties In today’s activity and later on we’ll take a look at mining for them!

Ore Minerals Minerals that are valuable and economical to extract Metallic or nonmetallic In extraction they must be separated from “gangue minerals” (useless) and then again to the target element Final price must be greater than the extraction/refining costs Can form in three ways: Cooling/hardening of magma (sink beneath) Crystallization from hydrothermal (hot) solutions Evaporation of water leaves “evaporites” (rock salts) behind Hydrothermal (hot water) solutions flow through cracks dissolving minerals, which then crystallize out when they have the space

Mineral Uses Metals – malleable, durable, and/or good conductors Combined to make alloys (best of both worlds) Nonmetals Gypsum – used to make Sheetrock (wallboard) for homes/buildings Gemstones – purely for their beauty or rarity! Stealth fighter aircraft – titanium!