The world’s soils hold around twice the amount of carbon found in the atmosphere and vegetation. Storing carbon in the soil has the potential to safely remove carbon from our atmosphere and store it in the soil for decades to centuries—by one generous calculation, we could sequester 100% of our annual CO2 emissions if all global cropland and pasture were transitioned to a regenerative system.
Other estimates are more conservative; and, of course, theoretical estimates are not the same as practical, measurable impact. Still, there is clearly potential—and a need to improve our understanding of how we could tackle GHG emissions in the wine and agriculture sector through soil health and regenerative practices such as:
Conservation tillage
Cover crops
Composting
Crop diversity
Animal/insect integration
Preserving wild lands
Holistic nutrient/fertilizer management
Practical Experience and Results from the Wine Sector
To explore how the wine sector can harness this potential, IWCA developed a concise practical report for our members. In addition to reviewing existing research on the topic, the report shares some of the soil health-building and regenerative farming practices and research undertaken by IWCA members—including Jackson Family Wines (in collaboration with the Soil Health Institute), Familia Torres (in collaboration with the Autonomous Barcelona University), and Cullen Wines.
Some of our main findings, drawing from these wineries’ research, include:
A combination of no-till and cover crops results in the highest carbon capture.
Minimum-till captures more carbon than conventional tillage, but less than no-till.
Cover crops that include grasses capture more carbon than legume-only cover crops.
Within grasses, cover crop species did not show substantial differences in carbon capture.
Perennial cover crops are expected to increase sequestration more so than annual cover crops, but there is not sufficient data to quantify the difference between annual and perennial cover crops.
There is insufficient data to estimate carbon capture from grazing, but it appears promising.
Nuanced Findings but Potential for Impact
We found vast discrepancies in soil carbon storage (sequestration) ranges among the different IWCA member trials. In the scientific research we reviewed, there also continues to be debate about how to quantify carbon sequestered, the permanence of sequestered carbon, and the role carbon farming can play globally in mitigating climate change. Therefore, IWCA believes that additional study and scientific research is required before we can come to a reasonable consensus on what the feasible sequestration range is for vineyard soils.
There is clear consensus amongst soil scientists, however, that all of the regenerative agriculture practices we reviewed benefit soil health and fertility potential. Moving forward, in addition to continuing to research the intersection between soil health and carbon sequestration, IWCA is interested in exploring how regenerative soil practices can lead to other positive vineyard farming outcomes, such as yield, quality, vineyard longevity, and farmworker health.
Read our Soil Health and Regenerative Farming report here.
