Celebrate Arbor Day (植树节)

People in many countries observe Arbor Day. If you want to make a contribution to our planet, you could start by reminding your family and neighbors of the importance of planting trees. 【小题1】 Following are some steps to help you choose and plant a tree.

1. Choose a tree that will grow well in your area. You should consider: how big the tree will grow, how long it will live, whether it produces fruit or flowers, and whether it attracts birds and other wildlife.

2. Decide where you will plant your tree. Remember that the tree’s root system and branches will need space to spread out and up, so you do not want to place it too close to your house or other buildings or other trees. 【小题2】

3. 【小题3】 Prepare a hole that is twice as wide as the root system of your tree, keeping in mind that it should not be too deep, as the tree needs to be level with or slightly taller than the ground around it. With a shovel, scrape the sides and bottom of the hole-this will help the roots work their way through the soil.

4. If your tree comes wrapped with burlap (粗麻布) around the roots, simply pull the cloth loose enough so that it falls around the root system in the hole.

5. Separate the roots slightly to encourage them to spread. Root tips die when exposed to light and air, so get the tree in the ground as quickly as possible. 【小题4】

6. Create a shallow depression (凹地) around the tree to collect water. Thoroughly water the tree and add mulch around its base to help keep the ground around the tree moist (潮湿的).

【小题5】 Because keeping your tree alive and thriving is an ongoing task.

Nowadays,human-polar bear conflict is on the rise. 【小题1】 Last year,there were 21 conflicts in the village of Ittoqqortoormiit,Greenland,alone. 【小题2】,as the changing climate reduces polar bears’ sea-ice habitat(栖息地)，and as humans take advantage of that ice loss in pursuit of economic opportunity.

Governments and industry leaders in Arctic countries must take responsibility and support ways for their citizens and employees to live and work safely together with potentially dangerous animals like polar bears,whose population will decrease by more than 30%by 2050 due to sea-ice habitat loss.

People living and working in the region need education,training and the necessary tools to protect themselves when faced with a polar bear. 【小题3】Patrolmen help to safely scare away bears that may wander into their streets,using bright lights,loud noises,and etc.

【小题4】; it’s also important to keep wildlife safe.There’s more to be done on national level.The five states with polar bear populations should keep their promise to work together on a 10-year plan to manage all aspects of polar-bear protection.

【小题5】By actively supporting the shift to a low-carbon economy,and by reducing our own greenhouse gas missions,we common people are each helping protect the sea-ice habitat that polar bears and other marine mammals all depend on.

Few sights fill you with nostalgia (怀旧) like the fireflies dancing at night. 【小题1】Their populations are declining around the world as the threats against them are increasing. Sara Lewis, an expert who studies the insects, offers tips on what you can do to ensure that fireflies will continue to light up your backyard.

Create a firefly habitat

【小题2】 With about 2, 000 different species of fireflies, there’s a wide variety of environments in which they thrive (繁衍) —including wetlands, forests, and even city parks—which is why some species are more threatened than others. “You can recreate those conditions in your own backyard simply by leaving some leaf litter around the edges of your property, “ Lewis says. ”That’s a good microhabitat for fireflies.”

【小题3】

Flashing lights are an important part in fireflies life. As the sun sets, male fireflies move around while flashing their lights to signal their interest. If a nearby female is interested, she flashes back from her position to the ground, and the males fly down to find her. “All of that has to happen for the next generation to survive,” says Lewis. “However, light pollution makes those scenes much harder to see. It’s like cutting a phone line. It really stops the romance. 【小题4】You can draw your curtains shut at night and turn off the lights completely when possible.”

Stop using pesticides (杀虫剂)

Using pesticides in your yard also poses an existential threat to fireflies, which are insects after all. 【小题5】. Scientists are researching alternatives to chemical pesticides that could target specific species, like mosquitoes, while leaving other insects unharmed.