UNSTOPPED TRACKS by sarahhill.designs

ECOSYSTEM ENGINEER ANALYSIS

INTRODUCTION TO SAMSONS PARK QUENDA SCALE ANALYSIS

LIFE OF A QUENDA QUENDA AS ‘ECOSYSTEM ENGINEER’ NATIVE VS NOVEL ECOSYSTEM

BALENCED ECOSYSTEM

HABITAT FRAGMENTATION

PERTH’S WETLAND SYSTEMS

02. THE PROBLEM “CROSSING THE ROAD”

HUMAN PERSPECTIVE QUENDA PERSPECTIVE

OPPORTUNITIES + THREATS

ECOLOGICAL LINKAGES

LAND USE LINKAGES

OPPORTUNITIES + THREATS

THE PROBLEM: QUENDAS CAN”T ‘CROSS THE ROAD’

03. NAVIGATING “CROSSING THE ROAD”

STRATERGY: UNSTOPPED TRACKS

DESIGN INTERVENTIONS

MASTERPLAN

04. LAYERS

BUFFER STRATERGY LAYERS

LAYER 1: CORE HABITAT

LAYER 2: SUPPORT SYSTEM

LAYER 2: OUTER LAYER PLANT PALETTE

ACKNOWLEDGMENT OF COUNTRY

In Australia we are always designing on country and therefore recognise the responsibility as landscape architects to acknowledge country, and to work respectively with direction of elders. By reading country as an intimate interconnected relationship. I would like to thank the people who have cared for the land and water on behalf of you and me for more than 70 thousand years.

WALK WITH ELDER TREVOR WALLEY

WALK WITH FRIENDS OF SAMSONS PARK

IMAGINED UMWELT OF QUENDA

DJERAN

URUKAM BIRAK

Dispersal of seeds and mycorrhizal fungi

Maintain soil health through turning over large soil volumes

Increases water ﬁltration

Decreases ﬁre leaf litter loads through digging

Perspective

Quenda

Story of Kwenda

“Kwenda had fire (karla) but he kept it hidden under his tail (nirnt), and would not share it. Djilidjili and Wata chased (moordalang) him until they reached…Kwenda’s uncle (kongk). Kwenda threw (koordidjiny) the fire (karla) to his uncle but a spark fell onto Wata’s beard (ngarnak) and smouldered. Overjoyed they hurried home (kala) putting a lot of fire (karla) into the balga, the kwel (she-oak) and the mangatj (banksia) but only a little (nyit) into the jarrah and marri”.

Native Ecosystem

Banksia + Jarrah Woodlands

Restored Ecosystem

Samsons Park

Novel Ecosystem City of Fremantle

Quendas are most commonly found in the dense understory of Banksia and Jarrah Woodlands. However, in an urban setting they are found in patches of bushland, parkland and backyard gardens.

The presence of quendas is a good indicator of a balanced ecosystem. Australia’s ancient landscapes have infertile, weathered, nutrient-poor soils that are especially deficient in phosphorus and nitrogen. The vast majority of native plants (including Eucalyptus species) have therefore evolved symbiotic relationships with mycorrhizal fungi, which increase the opportunities of obtaining nutrients and water resources. In return the fungi are provided with photosynthates from the plant. Many mycorrhizal species form above ground fruiting bodies, for example mushrooms, but there are also many more that form spore- filled fruiting bodies underground like truffles.

Quenda’s are essential in the distribution of these fungi as they consume the fruiting bodies and dig up and eat trufﬂes which moves the fungal spores around the landscape. The spores pass intact through their digestive tracts and are deposited in their feces. For some fungi, passing through the animal’s gut can break spore dormancy, leading to increased germination.

Mycorrhizal fungi are often not visible but underpin the health of many ecosystems and plant groups and are more important than ever in supporting the resilience of dominant trees in the face of changing climates.

DIGGING QUENDA NATIVE VEGETATION

MYCORRHIZAL FUNGI

Australian vertebrate fauna like the quenda rely on remanent bushland and wetlands. In their natural habitat they live in dense understory such as around swamps or in Banksia and Jarrah Woodlands. Many different Australian mammals dig in the soil for food or shelter. Sadly, most of Australia’s digging mammals are threatened with extinction and now have restricted distributions as their habitat is cleared for urban development and are preyed on by cats and foxes.

The urban landscape has changed over time and very few native mammal species survive fragmentation of native bushlands particularly the quenda. As its major current threat is loss of habitat due to land clearing for urban and rural use.

Waterways are the veins and arteries of the Western Australian vegetation. They extend from the deep river valleys, through forested wetlands to estuaries. Quenda’s rely on these water ways. To understand Perth’s wetland systems, I have learnt about Daniel Martin’s concept of Perth’s Three Coasts as a way to structure these water ways. The Three coasts categorizes Perth into broad environmental types in relation to urban heat, breeze, rainfall, vegetation, ecology, soil type and geology. This reveals signiﬁcant environmental variation across the Swan Coastal Plain from the Indian Ocean to the Darling Scarp. Our site falls within the second coast.

FIRST COAST

The First Coast is the sand and limestone coast at the Indian Ocean. Perth’s urban form is oriented to this First Coast and sprawls along it.

SECOND COAST

The Second Coast is formed by the chains of wetlands that run parallel to the coast, formed by the interdunal depressions where the groundwater mounds surface.

THIRD COAST

The Third Coast is the marshy and clayey high groundwater plain at the foothills of the Darling Scarp, Semeniuk (1987) called this the palusplain. Much of Perth’s projected urban sprawl is projected to occur in this region.

BUSHLAND + PARKLAND

The ecosystem services that quenda provide help to keep urban bushland healthy. However, urbanization has led to a loss of habitat along the second coast. Quenda’s are restricted to the pockets of remnant bushland that remains. Lack of habitat connecting these pockets leaves quenda’s vulnerable to predation by foxes, cats and dogs, lack of genetic connectivity, mating availability as well as road collisions. Therefore, we are left with the question of how do we ensure quenda’s can cross the road of urban fabric to connect the remnant vegetation and wetlands along the second coast?

CROSSING THE URBAN FABRIC:

Connect remanent patches of native habitat by improving the ecological linkages between remnant landscapes as part of a gradient of nature within second coast system

CROSSWALKS: MICROLINKAGES

Large scale regional linkages are important to connect ecological stepping stones, however there is a need for micro linkages to allow all fauna species to move between habitat areas. These micro linkages aim to mitigate the impacts of the hard-edge transition from urban development to a natural landscape.

QUENDA ZONES: BUFFER STRATERGY

A series of layers that acts as a natural gradient and serves as a signiﬁcant buffer zone around the biodiverse habitat core. The buffer plays a crucial role in shielding quenda and other fauna within a high-ﬁdelity landscape from invasive species, urban heat, industrial impacts and roads. This buffer strategy allows for these constructed areas to bleed into urban development to support a softer edge.

REDUCED USE OF ROADS AND VEHICLE SPEED IN QUENDA ZONES WITHIN ACTIVE TIMES (DAWN + DUST)

REDIRECT HUMAN MOVEMENT AWAY FROM CORE HABITAT TO LIMITED DISTURBANCE

CREATE HABITAT FOR ALL FAUNA TO MAINTAIN A BALENCED ECOSYSTEM

BUFFER SIZE IS TO REFLECT QUENDA HOME RANGE TO ALLOW FOR PROTECTION + GENETIC CONNECTIVITY

INCREASE QUENDA PERMEABILITY THROUGH RAISED FENCES TO ALLOW THE DISPERSAL OF FUNGI IN HUMAN CENTERED AREAS

REDIRECTION OF TRAFFIC THROUGH ONE WAY STREETS

CONSIDER THE VALUE OF STREETSCAPE VEGETATION AS WE MOVE TOWARDS MEDIUM DENSITY HOUSING

HABITAT + PRIVACY GRADIENT WITHIN LAYERS

PEDESTRIAN MOVEMENT PATHS TO PROVIDE EDUCATION OF INVISIBLE LINK BETWEEN QUENDA AND A HEALTHY ECOSYSTEM

L A Y E R 1: C O R E H A B I T A T

REGENERATE WETLAND ECOSYSTEM

RESTORE BANKSIA + JARRAH WOODLANDS

REFUGE EXTENTION BEYOND SAMSONS PARK

QUENDA ONLY LANEWAY POCKETS

PRIVATE NON HUMAN HABITAT

A Y E R 2:

PROVIDES LINKAGES BETWEEN CORE HABITAT POCKETS

RAIN GARDENS TO AID DISPERSION OF ECOSYSTEM ENHANCING FUNGI COMMUNITY WALKING TAILS EXTENDING BEYOND SAMSONS PARK EDUCATES THE ‘INVISIBLE LINK’ OF FUNGI AND HEALTHY ENDEMIC TREES COMMUNITY SHARED PATHWAYS: PEDESTRIAN, FAUNA + VEHICLES

VALUABLE VEGETATED STREETSCAPES AS MEDIUM DENSITY HOUSING INCREASES

L A Y E R 3: O U T E R L A Y E R

INCREASING HUMAN + NON HUMAN CONNECTION HUMAN RESIDENTS GARDENS THAT ARE REGULARLY VISITED BY NON HUMANS CREATING EMPATHY + APPRECIATION FOR QUENDA LIVING FENCES THAT ALLOW QUENDA TO MOVE INTO BACKYARDS OUTER LAYER OF BUFFER PROTECTION FOR QUENDA