Kakau Human Environment

Introduction
An ecosystem, according to Oxford Dictionary is “A biological community of interacting organisms and their physical environment” (Oxford University Press, 2017). An ecosystem can range in size from a large reef to a tree stump (University of Michigan, 2017), the range of ecosystems is staggering. This report will investigate ecosystems and the connections within them, using Kakadu National Park (Northern Territory, Australia) as a case study. This report will also cover the impacts that human activities have on these fragile ecosystems, both positive and negative.

The Importance of Maintaining Biodiversity for Functioning Ecosystems
In Kakadu, there are at least seven different biomes, types of ecosystem landscapes, in one small
area (UNESCO, 1999). All these ecosystems intertwine to make a unique and diverse landscape that is exclusive to Australia (Parks Australia, 2013). One of the most iconic in Kakadu is the dramatic stone country and southern hills. In this region of Kakadu, the Arnhem Land plateau exposes volcanic rocks that mix with the rich nutrients of the South Alligator river to foster plant and animal life (Australian Government, 2017). All animals and plants have to be able to withstand great heat (Mid March-October) and the tropical monsoonal rain (November-Mid March)(Brittanica, 2017).

The stone country has little vegetation, usually consisting of low shrubs and small bushes (Kleeman, 2009). The animals that live in the stone country are mainly small omnivorous mammals, such as wallaroos, bandicoots, quolls and possums. These animals eat insects, some grasses and shrubs and some small frogs, which makes them perfect for the harsh conditions of the stone country (Parks Australia, 2017). But it is frogs, the cane toad specifically, that has brought about a significant change to this ecosystem.

Circa 2000, the cane toad reached Kakadu - an introduced species originally brought over from South America for the control of the cane beetle (Australian Government, 2013). Unfortunately, the number of cane toads in Australia spiralled out of control and is destroying many natural ecosystems (Kleeman, 2009). The cane toads are poisonous and lethal to other animals. This became apparent in Kakadu when the number of Northern Quolls dropped dramatically. These small omnivorous marsupials eat frogs, meaning that the cane toad killed large numbers (Territory Wildlife Park, 2010). The number of Northern Quolls are dangerously low, roughly 100,000 and still declining (Australian Wildlife Conservancy, 2016).

The Benefits of Biodiversity for Humans
Biodiversity has a large effect on the social and economic stability of humans.
Having a range of natural resources provides for many human activities - for example, medicines from plants and fuels for cars. Different ecosystems create opportunities for humans. Many of Australia’s major ecosystems like The Great Barrier Reef and Kakadu create tourism opportunities. Kakadu alone attracts 300 000 tourists every year (Kleeman, 2009). This is due to the scenery, walking opportunities and the aboriginal culture that exists in the park (Tourism Australia, 2017). Having lived in the area for approximately 50 000 years, the Aboriginal communities and clans still live in Kakadu, living semi traditionally and offering unique insights into their culture (Parks Australia 2013). Kakadu is also unique because of the relationship between the government and the Aboriginal community. Having won the rights to the land in 1997, the Aboriginal community then leases the land out to the government for the use of tourism (Kleeman,2009) The local Aboriginal communities have used the biodiversity to run tours that showcase traditional hunting and other wildlife viewing tours (Kakadu Cultural Tours, 2015). This provides tourists with experiences and the local communities with
income.

Evaluation
Having humans living close to so many environments means that our activities can impact the ecosystems that are living around us, both negatively and positively. Large amounts of tourism in the park can have a negative impact for the ecosystems. Tourists in such large numbers means that infrastructure has to be built to accommodate people, therefore, detracting for some from the wilderness of Kakadu (Kleeman, 2009). Having tourists is one aspect, but tourist transport is another. Four-wheel-drives can create erosion and can permanently damage the soil and the plants that exist in the soil (Director of National Parks, n.d.). Having this increased amount of erosion in the soil also depletes water quality which in turn affects the aquatic life.

One of the ongoing environmental debates in Kakadu is mining (The Gundjeihmi Aboriginal Corporation, n.d.).
Large amounts of uranium ore, used for the production of nuclear energy, were found and large mining companies soon wanted to develop a mine (Kleeman, 2009). To protect the environment, the Federal Government inquired into the suitability for a mine, more specifically the Ranger mine, to be built in Kakadu (Kleeman, 2009). This report recommended a mine be built so an agreement was signed and the mine was opened in 1980 (The Gundjeihmi Aboriginal Corporation, n.d.). The Ranger mine’s sale of uranium ore has exceeded $3 billion (Kleeman, 2009). The mine uses water collected from creeks to extract uranium and then evaporates it into clean water to put back into the waterways (Energy Resources of Australia, n.d.). A large team of scientists make sure that the contaminant levels in the released water is low and healthy for the environment (Mineral Council of Australia, 2017). Luckily, this mine is safely managed and although there is huge potential for nuclear contamination there have been no major environmental impacts to date due to the large amount of government
regulation.

Although humans can cause negative effects, we can also positively change natural ecological issues. Humans have historically introduced many problem species to Australia such as rabbits, water buffalo, and cane toads (Australian Government, n.d.). After seeing the rapid decrease in the population of Northern Quolls, initiatives began to teach quolls not to eat cane toads. In 2014, the Australian Government initiated the Kakadu Threatened Species Strategy that would look into changing the course of threatened species’s decline in Kakadu (Australian Government, n.d.). One of the phases of the strategy was to teach a generation of quolls to not eat cane toads (Australian Government, n.d.) .

The program is run by Kakadu park rangers, Territory Wildlife Park and Sydney and Melbourne Universities (ReWilding Australia, 2017). Using a chemical that upsets the stomachs of quolls, the quolls are shown cane toad sausages and if they eat it, they have a sore stomach the next morning (ReWilding Australia, 2017). Using this non harming technique, quolls quickly learn that cane toad meat is to be avoided. Since the program started in 2010 by Territory Wildlife Park in Darwin, quolls have stopped eating cane toad meat and surprisingly, have taught their offspring to avoid cane toads as well (The Australian, 2016). After releasing trained quolls into Kakadu in April 2016, the same quolls had been tracked and all had survived (CaneToadsInOz, 2016). This is just one of the many examples of humans controlling introduced species to re-strengthen damaged ecosystems.

In conclusion, Kakadu provides a wonderful example of the importance of biodiversity for ecosystems in so many ways. Human impacts, both negative and positive, have shaped modern day Kakadu and continue to contribute to both the natural ecosystems and to supporting many human activities. Continuing to minimise the negative impacts is in turn another positive influence on ensuring this iconic location for future generations.