Bring Nature Home II
This post is continued from the last post called Bring Nature Home. I am going to share some personal thoughts or reading response for the book.
Although the maintenance and conservation of the ecosystem sounds not difficult due to the self-regulation of plants and wildlife, we still meet a big obstacle that human activities do intervened the nature negatively. Tallamy demonstrated this viewpoint by using his childhood experience about the observation of a small pond with pollywogs and how they grow up then gone away. He even witnessed extinction of local thriving communities of animals. (Tallamy, p26) As the human population grows up, the nature faced a big pressure and involved in the dilemma. When human begin to develop their living environment by using the landscape, they didn’t realize the serious breakup of the ecosystem. The speed of construction and removal of existing forest are much higher than that of building natural parks or preservation of wildlife. The best habitat for wildlife to live is the undisturbed land which is almost disappeared. When more and more buildings, infrastructures and industrial factories stand on our land, the natural habitats are no longer “natural”. Tallamy also mentioned an important result that larger scale of lands cause more new species created and less species extinct. (Tallamy, p29) The reason is that the huge size of continent will form a more stable and balanced space which can resist those natural disasters such as hurricane or earthquake. However, natural disasters are occupied small proportional parts of reason for wildlife extinction. Sometimes people didn’t realize their behaviors have causes the serious break up and damage on habitats. For example, the bird habitats have been reduced and 12% of bird species are endangered to extinct. (Tallamy, p34) Conservation of bird habitat needs more public attention and a systematic protection otherwise people will continue to hurt them and grab their home. (Tallamy, p36)
The author uses a good analogy model to demonstrate the importance of some specific species and explain the definition of redundancy. A plane can fly if it lost one or two small rivets but it cannot fly when it lost many necessary rivets. The ecosystem is also same. For instance, you remove some species in a pond and you find there is little influence on other remaining species because they can find substitute as food. However, if you remove the keystone species, the whole ecosystem food chain will be break up and some species will lost their food and cause more species died. (Tallamy, p40) However, the Jenga hypothesis proved that the ecosystem is not as simple as we thought. Its complexity refers to so many keystone species which hard to identify which one is more influential. Any species can have potential to affect the work of ecosystem. (Tallamy, p43) Biodiversity is also functional as efficiency in the ecosystem. Different plants have different efficiency. The more kinds of species the ecosystem have, the greater possibility those plants are efficient in using energy. Most people probably don’t know that biodiversity enable to provide more services and productive environment for us. It also can resist the alien invaders and reduce the negative effects on the ecosystem. (Tallamy, p43)
For next following chapters, Tallamy explore the reason why insects cannot eat alien plants in more details and examples. As I mentioned in previous paragraph, the long time to wait for the adaptation of insects on those alien vegetation are not suitable for the ecosystem. Also, most insects are specialists. They may give up those alien plants since they don’t share an evolutionary history. The preference or requirements of insects is hard to change or accommodate. Nevertheless, any rule cannot apply to every animal. There must be some accidental insects are able to accept the alien plants in a short period. That’s the charm of the nature. You never know when your conclusion will be overthrown by any new wildlife. The process of exploring the living habits of each plant is always full of surprising. The research shows that every insect also has its own favorite leaf chemistry. The chemicals play an important role in the “primary metabolism”. (Tallamy, p55)
When people realized that native is good for local ecosystem and alien ornamentals have so many disadvantages, another question raised by the author. Is there a standard to classify the native and alien plant? It’s hard to say a plant is native only because it grew at here for many years. Therefore, the best method to define the native plants is to let the nature to interact with the plants. Nature can prove which plant is “native”. The best example in the book is the Norway maple. It is originated from Europe but now it becomes one of the most popular trees in North America. The result wants to illustrated that the native plants are those which quickly and easily to adapt the local environment though it was discovered in other far island. (Tallamy, p67) Therefore, gardeners still can try to accept some “alien plants” in traditional thoughts and see what happened in the nature.
Although gardeners know that the alien plants are not as good as native plants, some of them may want to support the market of other countries. The alien plants will bring harmful disaster to the local ecosystem and threaten those native plants. They will grab the sun, water and nutrients in the soil which may cause the native plants loss a good living environment. Also, the alien ornamentals are possibly accompanied with alien insects. The gardeners haven’t seen that so it’s hard to eliminate them. (Tallamy, p75) Whether an alien plant is invasive or bad is depend on the plants. That’s also what the author wants to told us. Plant itself is hard to characterize or classify. The reaction between the plants and nature needs to be observed and investigated.
To summarize, the book systematically demonstrated the importance of preserving nature, keeping native plants and increasing biodiversity of plants and wildlife. It also provides very helpful and efficient information for us. As a landscape architecture student, I feel more curious and excited about future study about the plant design. As a reader of the book, I feel amazed about the complexity of nature and ecosystem and more interested in the relationship between plants and wildlife.
Tallamy, Douglas W. Bringing nature home: how you can sustain wildlife with native plants. Portland: Timber Press,2009