In Chapter 6 and 7 of the Rambunctious Gardens, Emma Marris discusses the concepts of exotic species and novel ecosystems. Exotic species are species that are not specific to an area but rather have been introduced by humans. There is a growing belief amongst ecologists that these species are invasive and detrimental to the new environments they are put in. Marris decides to use the concept of novel ecosystems to prove her view that exotic species are not detrimental to their new surroundings. Novel ecosystems are described as ecosystems that contain exotic species and can act better than native ecosystems. Along with that, they provide humans with services such as carbon sequestration and water filtration.
Marris argues that exotic species can be beneficial to habitats. They support rare native species, remove toxins from the soil, control for undesirable species along with regulating erosion. These exotic species may create even more diversity in the future by evolving and adapting to their new habitats. Marris likes to point out that many of the novel ecosystems that contain exotic species function better than none exotic ecosystems. Novel ecosystems have the most potential for evolution and increased diversity due to their need to survive by adapting to their new habitats.
Marris begins to question why we are inclined to dislike the introduction of new species. She believes that it is merely the fear and dislike of any change. People are quick to judge new species as invasive solely and solely welcoming native species into the ecosystems. Ecologist Mark Davis brings up the point that we should be dealing with each species as a separate case rather than categorizing each of these species as invasive.
Erle Ellis at the University of Maryland was the first to produce a map of the world anthropogenic biomes. This map revealed that 75% of the world’s ice-free land showed evidence of alteration as a result of human residence and land use. 20% of the world’s ice-free land is cropland; a third is rangeland and just under 22% showed no sign of human occupation or use (119). Later Ellis was able to discover that over 35% of the world’s ice-free land was covered by novel ecosystems. Another ecologist Mascaro, traveled to Hawaii’s Big Island and studied froty-six novel forests dominated by various species. He was able to discover that many measures of the novel ecosystem forests productivity such as nutrient cycling matched or out produced the native forests. Mascaro was later able to conclude that his novel ecosystems and native ecosystems were virtually indistinguishable.
I believe that novel ecosystems can be extremely successful. Firstly, they provide human services and secondly they are home to many diverse species. These new types of ecosystems will describe this age of species by helping diversify the ecosystems. These projects do not require large amounts of effort or money to complete making it a wise choice to continue doing what we already are doing.
