Chapters 8 & 9

Marris’ starts off chapter 8, Designer Ecosystems with the image of a stream. We all picture a stream to be clear flowing water, but that seems to be a thing of the past. Today, these streams have gone extinct and what remains are muddy streams branching off into several pools. Because of this, the rise of stream restoration communities have emerged. Some scientists argue on what the streams should look like. They have cleared trees and dramatically altered water levels for the sake of returning the streams to the pristine image they once held. Now scientists are worried and believe that efforts should be focused on solely reducing sediment load. Some even think that restoring the complex ecosystems will be too difficult. However, there is an alternative – to design the ecosystem for specific measurable goals such as “nitrogen reduction, sediment capture, or the maintenance of one or a small number of named species” (Marris Page 125).  Restoration ecologists are faced with the difficulty of not being able to reproduce the exact same ecosystem we once had, but instead, use “shortcuts” in an attempt to get close. Ecologists have changed their way of thinking, “Implicit in many restoration projects is the notion that a historical baseline is not just somehow morally better but ideal for restoring any number of features that a system might have lost over time, including biodiversity, ecosystem services, and recreational value” (Marris Page 126). The problem is that even if streams are restored to what they once appeared in historical times, it may seem restored to the naked eye, but it may not be performing to its natural historical level. Hence, a designer ecosystem may be better than this before mentioned restoration. Richard Hobbs, advocate of designer ecosystems, describes some terms, “Biotic changes are changes in the living components of an ecosystem … Abiotic changes are changes in the nonliving environment … when a site only shows one type of change, a hybrid ecosystem often results” (Marris Page 128). Despite the change, if the resulting environment has a use, it’s not the end of the world. We can take advantage of the new land and reap its benefits. Marris ends the chapter by declaring her wish to see nature run wild without human interference. Marris then goes into her next chapter titled Conservation Everywhere. She starts the chapter with a description of her visit to the Duwamish River. The river’s supporters are hoping to see a hybrid ecosystem where the river is part habitat and part industrial waterway. She explains that the value of conservation is to add more types of land to the list of hopefuls that can one day become of use. Some problems conservations are facing are due to the concept of species area relationship. The smaller the fragment becomes, the fewer species will remain. However, with corridors, species can migrate from one fragment to another. Conservationists are trying to create corridors however land ownership becomes an issue. The answer lies with agricultural and ranch lands which keep steams, lakes, and forested areas natural. Another problem is the fact that yield will decrease, so scientists are trying to come up with alternatives to using farm land for crop growth such as growing within skyscrapers. One idea is to introduce nature into city life, turning into a metapopulation. It involves a lot of compromise on part of the garden owners. Seemingly, this does not seem practical for most city dwellers.