Article Dans Une Revue Climate Policy Année : 2025

Carbon stocks and sequestration from small tree patches in grassland landscapes in Aotearoa-New Zealand

Daniel Richards
  • Fonction : Auteur
Kara Allen
  • Fonction : Auteur
Scott Graham
  • Fonction : Auteur
Nikki Harcourt
  • Fonction : Auteur
Nick Kirk
  • Fonction : Auteur
Sandra Lavorel
Sam Mcnally
  • Fonction : Auteur
Maksym Polyakov
  • Fonction : Auteur
David Whitehead
  • Fonction : Auteur

Résumé

Small patches of trees add structural heterogeneity to grassland landscapes, support biodiversity, and provide essential ecosystem services including carbon stocks and sequestration, erosion control, and shade provision. In Aotearoa-New Zealand (A-NZ) small patches of trees have further cultural significance within Te Ao Māori – the worldview of the indigenous Māori people. However, economic pressures have driven the management of grasslands either towards removing tree cover to enhance agricultural productivity, or large-scale conversion of grassland to production forests. Protecting existing small patches of trees, and encouraging their establishment across grassland landscapes, is challenging since the current extent and benefits of these patches is not known. This study demonstrates the critical contributions of small tree patches (those less than one hectare in area) in A-NZ grassland landscapes. Using a high-resolution tree cover dataset, we mapped 1,639,015 small tree patches in grasslands across A-NZ, with grassland small tree patches covering a total land area of between 185,589 ha and 187,928 ha. We used a probabilistic simulation approach to estimate carbon stocks and annual sequestration, revealing a potential aboveground carbon stock between 11.6 and 29.3 million tonnes (Mt) of carbon and an annual biomass sequestration of 0.3 Mt to 0.8 Mt. Despite their current exclusion from the national carbon emissions market, economic valuation suggests a liability of between $NZ 86.9 million and $NZ 8.6 billion (€47.9 million to €4.7. billion) if the small tree patches were felled, and a market value of between $NZ 2.0 million and $NZ 237.6 million (€1.1 and 130.9 million) annually for sequestration. Existing policies, including afforestation incentives, do not encourage protection or establishment of small patches of trees. Significant policy adjustments are required to recognize, protect, and incentivize the conservation and establishment of small patches of trees within grassland landscapes.
Fichier sous embargo
Fichier sous embargo
0 3 17
Année Mois Jours
Avant la publication
jeudi 22 mai 2025
Fichier sous embargo
jeudi 22 mai 2025
Connectez-vous pour demander l'accès au fichier

Dates et versions

hal-04799506 , version 1 (09-01-2025)

Identifiants

Citer

Daniel Richards, Kara Allen, Scott Graham, Nikki Harcourt, Nick Kirk, et al.. Carbon stocks and sequestration from small tree patches in grassland landscapes in Aotearoa-New Zealand. Climate Policy, In press, ⟨10.1080/14693062.2024.2427710⟩. ⟨hal-04799506⟩
20 Consultations
3 Téléchargements

Altmetric

Partager

More