Biodiversity loss As a result of the Anthropocene mass extinction event, scientists estimate that 68 percent of plant species are threatened with extinction. Across the world, a pitched battle is being fought against the twin forces of climate change and habitat destruction to save the world’s plant species – and seed banks and repositories are a crucial part of the effort.
In order to save as many species as possible, governments, universities, businesses and NGOs across the world are working to create gigantic repositories of seeds, to be stored in case of their extinction in the wild. Thus, future generations may have a chance at rebuilding past biodiversity.
The Anthropocene Extinction Crisis
According to the Center for Biological Diversity: “Our planet is now in the midst of its sixth mass extinction of plants and animals – the sixth wave of extinctions in the past half-billion years. We’re currently experiencing the worst spate of species die-offs since the loss of the dinosaurs 65 million years ago”.
Unlike the extinctions that have occurred in the past (which were typically a result of volcanic eruptions, meteorite impact, or glaciation), the current extinction crisis is occurring as a direct result of human activities. Human activities that drive habitat loss and climate change, or that introduce foreign genetics into a population, are the most harmful of all.
No species exists in isolation – each depends on others for its survival, for food or for various other symbiotic relationships. For example, many flowering plants (including many food crops) require pollinating insects, hence why global threats to honeybee populations are being taken so seriously. Due to these interdependencies, the extinction of one species can destabilise an entire ecosystem, and spark off a chain of extinctions.
Plants are the fundamental backbone of the world’s ecosystems. They nourish the atmosphere with oxygen produced via photosynthesis, and are crucial to maintaining the balance of the hydrological cycle. Furthermore, many essential medicines are derived directly from specific plants – so every time a species goes extinct, we could be losing out on as-yet-unknown beneficial compounds!
How Biodiversity Loss Affects Us All
What is even more bewildering is that it’s not just the wild ecosystem that’s suffering – even our traditional, diverse forms of agriculture are dying out and being replaced by large-scale, intensive monoculture of a comparatively tiny number of varieties. Tens of thousands of different varieties that human farmers have nurtured, preserved and developed from simple wild origins over millennia to become unique, productive heirloom crops – all are at risk (or have already disappeared) from this cavalier approach to agriculture.
The reduction in the number of varieties (and overall genetic diversity) of grain, fruit and vegetable crops is termed genetic erosion. According to National Geographic, we have suffered a 93 percent loss in diversity of food crops since 1903 – we now have just 36 commercial varieties of lettuce, for example, compared to 497 at the turn of the 20th century!
Loss of plant biodiversity, whether in our wild ecosystems or of our selectively-bred and managed heirloom crop varieties, affects all humans and animals that depend on them. As we erode our genetic diversity, we are exposing ourselves to multiple dangers – many of which are not immediately apparent, or easily fixable.
Sustaining genetic diversity offers multiple advantages. For example – cannabis, which is a highly genetically-diverse genus, has multiple “options” it can express according to environmental requirements. In humid environments, individuals that resist mould and fungus may become dominant; in dry environments, individuals that can resist drought may dominate. In temperate zones, cannabis flowers according to day length; in the tropics and the far north, it has developed non-photoperiod dependent populations to better take advantage of available light.
Genetic diversity offers a species the tools to survive. If a new disease of pathogen attacks a species, the greater its degree of genetic diversity, the greater the chance that genes for resistance are present. With a genetically-uniform crop (such as the Gros Michel banana in the 1950s), a single pathogen can wipe out an entire population.
Seed Banks & Repositories Around The World
Over the last few decades, as the realities of declining biodiversity have become apparent, the need to preserve our dwindling pool of plant species has become clearer than ever. To this end, institutions, governments, and supranational organizations have banded together to create over one thousand seed banks throughout the world. Let’s take a look at some of the principal efforts being made.
In Norway, the “Doomsday Vault” (more properly known as the Svalbard International Seed Vault) lies buried deep within an Arctic mountainside in Longyearbyen, capital of the island of Svalbard. The Doomsday Vault holds approximately 1.5 million seed samples, and is built to withstand earthquakes, bombings and tsunami.
The UK’s Millennium Seed Bank is the largest of its kind, and it located at the world-famous Royal Botanical Gardens at Kew, London. The Vault currently holds some 13 percent of the world’s wild plant species – and aims to hold 25 percent by 2020 (an incredible 75,000 unique species!).
In the U.S., the National Plant Germplasm System (NPGS) preserves plant genetic diversity in a collaborative effort between state, federal, and private companies. The NPGS preserves landraces, archaic cultivars, wild and feral crop relatives, as well as elite crop lineages. One of their most important locations is in Colorado, at the National Center for Genetic Resources Preservation.
The Colorado site holds one of the world’s largest collections of seeds, and implements such high-level security and environmental control that other seed banks store their backup collections here. The facility’s gleaming shelves with their endless rows of packages hold billions of seeds, all catalogued and organized using a sophisticated barcode system, and kept at the precise low temperatures and humidity needed to maintain viability for as long as possible.
Why Cannabis Needs Preservation Efforts Too
The many varieties of cannabis have huge and varied potential in medicine and a hundred other applications, and as such, it’s vitally important to preserve these genetics too. Some government-run seed banks hold preserves of hemp seed, which is of course of incalculable importance, but for high-THC cannabis genetics, the best place to look truly is a cannabis seed bank such as Sensi Seeds.
Cannabis seed banks that do a methodical, rigorous job can really contribute greatly to the efforts to conserve plant species and varieties by maintaining their breeding programs effectively. Typically, this means retaining a substantial pool of the original parent seed stock and keeping it in long-term storage. Then, subsequent generations of plants can be regularly backcrossed with parent stock in order to prevent genetic drift.
One thing that a seed bank should not do, except in specific, precisely-managed cases, is to release non-native genetic material into a wild or landrace population. Cannabis has multiple populations all over the world that have been isolated for long enough to establish unique characteristics. These populations were mostly established by humans as we spread across the planet, taking our crop seeds with us as we went.
So if humans originally created these unique, “landrace” populations, don’t we have the right to destroy them as we see fit? What difference would that make?
Why We Need To Preserve Remaining Landrace Varieties
Although cannabis as a species is one of the most widespread and successful crops on the planet today, this does not tell the full story. The cannabis genus is made up of countless interfertile but diverse populations, which together comprise a vast pool of genetic material. When a new cannabis plant develops, it has the “choice” of countless genes that may help it in its particular environment.
When humans originally spread cannabis genetics throughout the world, our human population was much smaller than it is today, and the possibilities for our population centres to overlap and overspill in the manner that they do now were not present. Having various, scattered population centres allowed populations of cannabis to become established with minimal ongoing involvement of non-local genetics.
While transfer of crop varieties and genetics has of course been occurring for millennia, the trend towards globalization that has occurred over the last century has set the stage for incredibly rapid, chaotic and messy transfer of genes, all over the planet. Added to that are the forces of habitat destruction – as humans destroy wild plants to make room for agriculture, grazing land and settlements – along with rising temperatures, pollution of wild habitats, and the rise of new or more virulent pathogens.
Lastly, the rise of the commercial cannabis industry has created a vast pool of hybrid genetic material, comprised of varieties from all over the world, jumbled and mixed together with very little coherent or discernible strategy. A hybrid of Thai, Afghan and Mexican landraces may perform wonderfully indoors in a controlled environment, but what natural habitat will it thrive in, given the dramatically different climatic conditions between locations its parents evolved in?
For this reason, even if a commercial landrace has qualities that make it seem preferable or better to a landrace variety (maybe it has more resin, a bigger yield, a better smell), this does not equate to the plant being better equipped to deal with local climatic conditions.
Furthermore, introducing foreign genetics could introduce unhelpful or even harmful genes. If a landrace population well-adapted for drought resistance is invaded by a moisture-loving variety from the tropics, the landrace population could end up several generations later with a reduced ability to deal with drought.
If a landrace that has developed genes that resist a certain local pest or disease, introducing non-resistant genes could harm the population – just as allowing more than a certain number of human children to go unvaccinated can have devastating results on herd immunity against diseases such as measles and tuberculosis.
What Can YOU Do To Help Preserve Plant Species?
Every one of us can be actively involved in helping to maintain plant biodiversity, with minimal effort! Here’s a few different ideas.
If you have a garden or any outdoor space at all, plant natural wildflowers, and even weeds (some can be aesthetically pleasing and will attract abundant bees and butterflies). Encourage friends and neighbours to do the same! Lobby local government to plant and maintain wildflowers on roadsides, in parks, and so on.
Look for diverse cultivars when buying fruits, vegetables and cereals. This may mean moving away from supermarket shopping and taking advantage of local farmers’ markets, which usually offer a vast range of different varieties compared to the average supermarket. Or better yet, grow your own!
Look into joining an organization dedicated to maintaining plant biodiversity, such as within the Heirloom Seed Movement. There are now thousands of groups, clubs and cooperatives that have sprung into existence to deal with this issue head-on. This is where “thinking local” really comes into play – most of the benefits of biodiversity are felt on the local level, and so it is vitally important to conduct conservation at the local level.
Lastly, why not consider volunteering at an institution that dedicates efforts to preserving plant biodiversity? The Millennium Seed Bank at Kew is happy to take on volunteers to assist with cleaning and preparing seeds for storage, along with various other essential tasks! As well as contributing your efforts, this could also provide a valuable way to meet like-minded people and to learn more about the battle to preserve our plant species.