RM Journal

The Natural and Built Environments Ecologies Act: bringing the ‘hidden infrastructure’ to light

 

Author: Dr Steve Urlich, Senior Lecturer in Environmental Management, Lincoln University

Over 200 years ago, the renowned scientist and naturalist Alexander von Humboldt drew attention to the effects of deforestation on soil erosion, sedimentation of waterways, and its disruptive effects on climate.

Travelling through Venezuela in search of the source of the Orinoco River, Humboldt’s description of land use practices is eerily reminiscent to clearfelling today on steeplands in Gisborne, Tasman and Marlborough:

“When forests are destroyed…whenever great rain falls from the heights…the waters falling in rain are no longer impeded in their course; and instead of slowly augmenting the level of the rivers by progressive filtration, they furrow during heavy rain showers the sides of the hills, bear down the loosened soil…[and] devastate the country” [Andrea Wulf “The invention of nature” (2015) John Murray].

Humboldt described nature as a “living whole” with a “net-like intricate fabric” of organisms, which are “made mutually dependent on each other”, in laying the foundations for the modern science of ecology [Wulf at 245]. This interdependent and interconnected view is also reflected in Te Ao Māori and other Indigenous cultures.

Since Humboldt’s time, many ecological studies have revealed the importance of diversity in biological communities for ecosystem stability and resilience. Resilience can be defined as the capacity of a habitat or ecosystem “to absorb disturbance or reorganize while undergoing change so as to retain essentially the same function, structure, identity, and feedbacks” [Carl Folke and others “Regime shifts, resilience, and biodiversity in ecosystem management” (2004) 35 Annual Review of Ecology, Evolution, and Systematics 557].

Unfortunately, our forestry and fishing methods often involve extensive clearfelling to extract fibre or protein. These methods destabilise soils and sediments resulting in sedimentation and habitat damage from heavy machinery. Not only are hillsides being eroded at an alarming rate, but old sediments that are a legacy of past mining, deforestation and pastoralism are remobilised into the water column by heavy dredges and trawl gear.

These practices occur annually over millions of hectares of land and sea each year [Ministry for the Environment and Statistics New Zealand “Environment Aotearoa 2019”]; are inimical to ecological resilience and biodiversity; and contribute to climate change by releasing labile carbon into the water column where conversion into carbon dioxide by remineralisation can occur and emission to the atmosphere [New Zealand Marine Sciences Society “Submission – Climate Change Commission: Draft Advice for Consultation” 2021].

Read the full article