Medicinal plant resources are highly valuable for the environment, the livelihoods of local communities and the economy of Bulgaria, but they are also highly vulnerable. This is why we need to know exactly what quantities exist and where they are. Only armed with this knowledge can we correctly determine how to utilize medicinal plants, so as to allow them the opportunity to renew themselves successfully and survive for years to come. This is called sustainable use.
The main goals of resource assessment are:
- To determine the location of economically valuable medicinal plant populations.
- To determine the usable reserves – the amount of useful biomass, which can be collected from all of a given species’ exploitable populations on a given territory.
- To determine of the possible yearly yield.
- To create directions for use and conservation.
Determining the quantity of plant material, which may be used is important for two reasons:
- Firstly, in order to protect the populations and introduce conservational measures. The resource assessment allows us to determine what part of the plant material may be used without harming the population and threatening its long-term renewal and survival.
- Secondly to determine the economic potential of the resources and plan and organize the collection of plant material as well as to orientate the collectors and buyers as to the amount of herbs they can expect to get from a certain population.
The Medicinal Plants Act lays down the following requirements for the assessment of resources:
The municipal development plans (Municipal Nature Conservation Programmes); the protected area management plans, and the forestry enterprise management plans and programmes must include a specially formulated “Medicinal Plants” section. It must include a description of the location of the natural plant habitats, the conditions in them, as well as an evaluation of the quantity and condition of the resources. Based on this evaluation, decisions about whether plant material should be collected and how much can be picked from a specific population of a given species can be made.
HOW IS THE RESOURCE ASSESSMENT PERFORMED?
Dense, accessible habitats, far from roads, landfills and other pollutants, which are suitable for medicinal plant collection, are chosen. Their location and size are described. This is done with a GPS device and the data gathered is fed into an electronic database in a geographic information system (GIS).
A Russian “Methodology for the determination of medicinal plant reserves” (1986), successfully adapted and applied by the Ministry of Environment and Water and other institutions in Bulgaria is used to evaluate the amount of biomass a given species produces. The Institute of Biodiversity and Ecosystem Research at The Bulgarian Academy of Sciences and other scientific institutes have experts, who are qualified to carry out such assessments. Municipal ecology experts, herb buyers, collectors and forestry unit workers must also participate in the evaluations. This is how they learn about medicinal plant species and economically valuable habitats, which, in turn, enables them to plan how much biomass should be collected from them. The quantities are determined in compliance with the conservational measures, allowing resting periods in order for the habitats to renew themselves.
Monitoring is the observation of the development and health of plants and their habitats. The monitoring results are important for the conservation and sustainable use of the medicinal plants and help to determine the correct time for collection. Every year, as a result of the specific yearly weather conditions, the developmental phases of the plants (development of vegetative organs, flowers, fruit formation, etc.) set in at different times, which also affects the time of collection.
Monitoring registers meteorological phenomena, such as strong winds, torrential rains, hail or spring frost, which can cause serious harm and reduce economic productivity. For example, late frosts and torrential rains during flowering can lead to reduced pollination and fruit formation, which, in turn, can cause whole plant populations of species like bilberry, dog rose and blackthorn to yield low quantities of fruit.
In Bulgaria there is A National System for Monitoring of Biological Diversity, which is part of The National System for Environmental Monitoring, carried out under the guidance of the Executive Environmental Angency. The list of vascular plants included in the National System for Monitoring of Biological Diversity includes more than 20 medicinal plant species.
Declaring protected areas like nature reserves, national and nature parks and protected zones is one of the most successful approaches toward the protection of medicinal plant habitats and populations. Special measures and limitations for the use of medicinal plants apply within such areas. This protects populations, which are a valuable resource for scientific studies and training as well as a source of genetic material for the recovery of damaged or destroyed habitats. A good example of this is Central Balkan National Park, which hosts and conserves the habitats of over 166 species, or 66,4% of all medicinal plant species in Bulgaria.
A large number of protected zones in the country were established with the goal of safeguarding rare medicinal plant species in mind. An example of this exists in the Plovdiv province – the protected habitats of the loddon lily (Leucojum aestivum) in the Parvomay municipality.
Conservation measures for the protection of habitats include: maintaining the conditions which the given plant species requires – humidity, light, shelter from the wind; aiding the plant’s development by spreading seeds of the species, etc. The main approaches for the protection of habitats are the following:
- Leaving part of the best specimens for natural seed reproduction and recovery of the population.
- Not collecting from the same population every year and allowing the resources a period of recovery.