Five years ago, algae was the “it” feedstock in the biofuel realm. The idea of taking an organism that feeds off of CO2 and using it to create fuel was as intoxicating to research scientists as it was to venture capitalists. Financing was available to fund the placement of extremely expensive photobioreactors next to power plants. Decades-old research from the National Renewable Energy Lab proved that some strains of algae could effectively be used to create high-grade fuels. Startup CEOs talked of being able to produce algae-based biofuels cheaply and at a large scale within the three to five years.

While this guide to important environmental issues is not comprehensive, if you’re new to green or simply want a refresher overview, this list neatly summarizes some of our most pressing environmental concerns … some of which cannot be solved simply via creative upcycling or small-space living.

In the developed world, citizens take advantage of the enormous bounty of meat while shopping at markets and dining in restaurants. For some, a meal can only be classified as real if it contains some kind of meat in it. According to the UN, the attitude towards meat consumption has to change, and people must cut back. This is a necessary step in reducing one of the most potent greenhouse gases, nitrous oxide (N2O). A recent study by the UN Intergovernmental Panel on Climate Change (IPCC) suggests that the developed world needs to cut its meat consumption by 50 percent per person by the year 2050.

If you need more proof that climate change is destroying the world, consider your favorite foods and beverages. Changing temperatures, unpredictable rainfall, and record droughts are affecting production of honey, coffee, chocolate, and bourbon—just to name a few. Do you want to live in a world with no coffee, no chocolate, and no bourbon? Didn't think so.

As a child in elementary and middle school I was always sent to school with a funky looking lunch box or bag. Inside my personal lunch container were items most kids had never seen or heard of. I had rice milk in a box, multi-grain sprouted bread, sprouts on my sandwich and organic peanut butter with organic jelly. I had carrot sticks for snacks while the majority of my friends got fruit roll-ups and yogurt that came in a tube and squirted fun, bright colors. I was always jealous of my friends who got to eat hot lunch and enjoyed their tater-tots and school lasagna, even though they often said it was gross. It looked and smelled so much better than my box of organic raisins or my local, organic broccoli florets! I was constantly made fun of for having different food than everyone else. Sometimes my friends wouldn't even sit with me because I had such "weird food." I was poked and made fun of for having different food everyday.

Today, as a young adult, and after being educated about fast food, I could not be more grateful to my parents for feeding me healthy, nutritious snacks during my school day. After hearing an odd rumor that the meat served in schools is the meat that fast food chains and grocery stores reject, I decided to do my own research. It turns out, the rumor is true. This doesn't help considering that, as President Obama stated in 2009, for many children, school lunches are "their most nutritious meal — sometimes their only meal — of the day."

The proliferation of labels and claims at the grocery store can befuddle even the most conscientious consumer. What to buy? Organic produce? Locally grown vegetables? MSC-certified fish? Fair Trade coffee or chocolate?

Paul Rice, the president and CEO of Fair Trade USA, isn’t worried by the clutter. All the labels, he says, reflect a big trend–the growing appetite of food shoppers for  more “transparency and traceability.”

"If you do just one thing -- make one conscious choice -- that can change the world, go organic.... No other single choice you can make to improve the health of your family and the planet will have greater positive repercussions for our future."

As we've come to depend on a handful of commercial varieties of fruits and vegetables, thousands of heirloom varieties have disappeared. It's hard to know exactly how many have been lost over the past century, but a study conducted in 1983 by the Rural Advancement Foundation International gave a clue to the scope of the problem.

It compared USDA listings of seed varieties sold by commercial U.S. seed houses in 1903 with those in the U.S. National Seed Storage Laboratory in 1983. The survey, which included 66 crops, found that about 93 percent of the varieties had gone extinct. More up-to-date studies are needed.

Mark Bittman says you can start by changing what you eat.

In his book, Food Matters, The New York Times food columnist writes about the environmental impact of industrial farming — and how individuals can make a difference by cutting down on the amount of animal products they consume.

I enjoy a good steak. Also chicken, fish, and the occasional pork or lamp chop. Red meat in moderation, to be sure, and not enough fish, but I’m moving in the “right” direction on these matters. I have respect and appreciation for vegetarians, or vegans, but it is not a path I choose. The model I want to try to follow is Mark Bittman’s formulation of mostly fruits and vegetables, grains, etc., with an occasional modest helping of meat.