Existing structures in the area that restricted the activity of wildlife were also torn down.
Only about three years have passed since Guo took over the area but there's been spectacular progress. Today, his special zone boasts 300 types of native plants and 800 animal species, and nonnative species account for no more than 5 percent of the overall plant and animal population.
More than five types of native frog have already been spotted in the area, and more native species will follow when the natural environment improves further, says Guo.
Birds like the Japanese waxwing can now be found spending the winter in the area. Other species of animals like northeastern hedgehogs and yellow weasels have also reappeared over the years.
"The water quality of streams is usually affected by urban expansion and this is one major issue we have been working hard to address. In fact, we have already seen the results. A rare species of tortoise has appeared in the streams we created. Seeing them here is an affirmation that our efforts are paying off," he adds.
