Cork around the Mediterranean

Background

Cork Industry

Cork is a natural, environmental and renewable industrial raw material, and is typically Mediterranean in the sense that this area is home to the majority of cork oak forests and the most cork extraction activity. Cork is very useful to produce different kind of products such as insulators, floorings, boards, insoles so on. But, the products that represent the most importanteconomical resource are the natural cork stoppers to top still wine.

The cork industry originated as small craft workshops in Catalonia, Northern Spain, that manufactured cork stoppers mainly exported to France. In the second half of the 19th century, the industry became industrialized and hit its peak in the beginning of the 20th century. All cork oak forests are private and have a landowner or proprietor. Usually each forest is managed by a familiar company that passes the property from generation to generation.

Natural versus Plastic Cork The value of natural cork has gone up in the recent years and in 1990 the production of synthetic, or plastic, corks paved the way for a new wine stopper. The new synthetic cork was able to increase the shelf-life of wine up to 2 years longer. The characteristics of natural cork stoppers are hard to control and synthetic stoppers allow companies to create a stable stopper because natural corks all have different structures so there is no telling how long that cork will last.

Sources: - Costa, A., H. Pereira, and A. Oliveira. 2004. The effect of cork-stripping damage on diameter growth of Quercus suber L. Forestry. 77(1): 1-8. - Gabarrell, X., J. Rives, J. Rieradevall, I. Fernandez-Rodriguez. 2001. Life cycle assessment of the industrial production of natural cork stoppers for still wine. eBook. - Rives, J.B. 2011. Environmental evaluation of the cork sector in Southern Europe (Catalonia). Bellaterra. 2- 177. - Silva, A., M. Lambri, M.D. De Faveri. 2003. Evaluation of the performances of synthetic and cork stoppers up to 24 months post-bottling. European Food Research and Technology. 216(6): 529-534.

Put a CORK in it

Jeremy MannyGeorgia College and State University

Geography 4400 Fall 2012

Impacts

Introduction

The cork oak tree (Quercus Suber L.) is a native, endemic and evergreen species from the Fagaceae family, that grows in western Mediterranean forests (Figure 1). The first cork oak trees occurred millions of years ago during the Pleistocene Era and through time the species located to areas with a more benign climate. Worldwide, cork oak forests occupy between 2.3 to 2.4 million hectares; 1 hectare is equal to 10,000 square meters. Yearly, 300,000 to 374,000 tons of raw cork is extracted. Cork oak forests are concentrated in 7 countries (Figure 2): Portugal, Spain, Algeria, Morocco, France, Tunisia, and Italy. The Iberian Peninsula concenters 82% of the world production. Most of the present cork oak forests appeared from the mid 19th century due to the increasing value of cork and the demand for cork stoppers. These forests provide other goods such as public recreation and offer indirect environmental services: wildlife habitat, soil erosion, carbon storage, and hydrology regulation, just to name a few. Cork is composed of dead cells with walls that are impermeable due to suberin, a chemical compound that makes cork what it is.

Figure 1: A cork oak tree that has been recently harvested because of the light brown bark that is now exposed.

(https://onflooring.com/about-cork-flooring)

Figure 2: The totals of the world cork oak surface (A) and the totals of the world cork yearly production (B).(http://www.tdx.cat/bitstream/handle/10803/51440/jrb1de1.pdf?sequence=1)

Figure 3: Cork stoppers being produced straight from the cork slab. (http://citywineryblog.com/tag/cork/)

There are 3 stages in the extraction of cork off of the cork oak tree. Cork StrippingThis stage begins every 13 years at the beginning of summer, June and July, and each team of workers extract 500 kg of raw cork/day. Manual stripping is performed by men with axes who make long cuts, vertically and horizontally, allowing large pieces to be peeled off. The cork cambium is destroyed, but proper sustainable production allows for regeneration of the cambium. All the cork slabs are loaded and transported to meeting points by all terrain vehicles. This stage accounts for 66% to 76% of the environmental impacts of harvesting cork. ScratchingThis stage is carried out 3 years after the stripping stage and is done to facilitate future cork extraction. Workers put vertical incisions into the trees to facilitate the regrowth of the cork bark which prevent fractures and promote good quality bark. Shrub Clearance and Road MaintenanceThis stage is done is to increase the yield of cork by reducing the neighboring shrubs and trees. New roads are also created in order to destroy these shrubs.

Cork oak forests are being abandoned due to decreasing profitability and if exploitation of the abandoned forests could result in fires and less soil erosion.