In the 2010s, 34-year old Brianne Miller travelled around the world as a marine (海洋的) biologist. No matter how remote the location, she made the same alarming discovery: large amounts of plastic polluting the water and threatening marine life. Miller knew she needed to do something.

Canadians throw out three million tons of plastic waste each year, 33 per cent of which comes from food packaging. Miller, determined to solve the problem at the source, envisioned a shop that not just banned the use of plastic bags—a place that avoided both wasteful packaging and the bad habit of wasting food itself.

To put her thought into practice, in June 2018, Miller opened one of the first zero-waste grocery stores in Canada. She named it Nada. You can bring your own containers (容器), though it’s not necessary: right by the front door are recycled glass or plastic containers, free for the taking.

The early days of the pandemic (疫情) were hard on the business. Because food sales were restricted (限制), Nada closed its doors to the public for 18 months. But then Miller turned to online ordering and delivery. The zero-waste deliveries are made by e-bike and electric vehicles. Everything from olive oil to fresh eggs comes delivered in recycled containers, which are collected and reused for the next round of deliveries.

Those containers do so much more than just reduce waste. They get people thinking big, just as Miller had hoped they would. “You can see how many times the container has been used,” she says.

“One person’s trash is another person’s treasure.” That’s a common expression, but the next time you throw something away, think about a twist on the old saying. What if your trash could become your own treasure? Many creative, thrifty, and environmentally minded people have come up with a way to make that happen. It’s called upcycling. Our world would be a better place if everyone would begin upcycling.

Upcycling is the practice of taking an unwanted item and turning it into something useful. For example, how about that pair of jeans with a hole in one knee? It could become a new pillow for your bedroom. How about the old T-shirts you never wear anymore? It could be sewed together to make a picnic blanket. All of these are examples of upcycling.

Upcycling is not the same as recycling. Upcycling is actually much better for the environment. Recycling takes an item made of glass, paper, metal, or plastic, breaks it down to its base material, and then uses that material to make another product. This requires a great deal of energy. On the other hand, when you choose to upcycle, the only energy you use is your own. And upcycling not only reduces the amount of trash that goes into our landfills, but it also protects natural resources, such as oil and gas. Recycling is good for the environment, but upcycling is even better.

Upcycling also makes a family’s budget stretch further. Before you run to the store to buy something, look around your house. Old teacups can be transformed into candles. And an old ladder can even become a bookshelf. Of course, the idea of reusing items to save money is not new. During the Great Depression in the 1930s, many families lived on a tight budget. People had to use what they already had in order to meet their needs. Flour sacks were used to make clothes, and a broken door became a new table. Today we should follow the examples of our great-grandparents and save money by upcycling.

As responsible citizens, we should all be concerned with protecting our environment and budgeting our resources. Upcycling is a fun and creative way to help. The next time you go to toss something into the trash can, stop and think about what it could become. Chances are, there’s a brand-new item in your hand just waiting to be upcycled.

Have you ever noticed tiny raised areas on the branches of a tree? These may have been insects. These small insects feed on tree sap (汁液). Insects on urban trees are notably more abundant than those on rural trees. As a result, urban trees suffer from heavy infestations (害虫横行), and are often unhealthy or die. To protect and restore urban trees’ health, we need to determine the factors that make these tree pests more successful in urban habitats.

Living organisms interact closely with their environment. The warmer, more drought-stressed trees harbor more successful pests than cooler, less drought-stressed trees. As cities and natural habitats become hotter and drier, damaging insects will become more abundant on urban trees.

Trees within urban forests are valuable economically and for the environmental sustainability (可持续性) of the region. More than half of the world’s population lives in cities. Across the globe, people are moving into cities at a faster rate than ever. Rapid growth may turn cities into places with harder conditions. Although cities are primarily made of buildings, roads, parking lots, and vehicles, there are still plants in them. The trees within a city are referred to as the urban forest. Urban forests offer very big benefits to human and environmental health. They improve air and water quality, provide habitat for wildlife, cool down temperatures and beautify our environment. They make cities livable.

However, being a city tree is not easy. Heat released by human activities is trapped in cities. As a result, temperatures in urban areas are often warmer than their surrounding rural areas. We call this urban warming or the urban heat island effect. Urban habitats are mostly made of surfaces of asphalt (沥青) and concrete. These surfaces reduce the amount of rainwater that reaches tree roots. As a result, urban forests may suffer, which can negatively affect people and the environment.

What can we do to restore urban forests? Regular irrigation when possible may help keep pest populations under control. Planting tree species that are suitable to handle heat and drought stress would also reduce the occurrence of insect pest outbreaks.