Damage caused by singing cicadas (Hemiptera: Cicadidae) in the field protective forest belts in South Dobrudzha, Bulgaria

During the period 2020-2023, strong damage caused by singing cicadas (Hemiptera: Cicadidae) were registered on ash trees (Fraxinus spp.) in the field protective forest belts (FPFBs) in South Dobrudzha, northeastern Bulgaria. Bioacoustic studies have shown that the sounds are of Cicada orni. Many exuvia of the species were also found on the trunks and branches of ash trees. On the upper shoots and petioles, numerous oviposition holes were observed, which lead to leaf fall and drying of branch tips. In different FPFBs, tree crown damage ranges from a moderate (25-60% defoliation) to a severe (over 60% defoliation) degree. The attacks were stronger on Fraxinus excelsior and F. americana compared to F. angustifolia. The cicadas affect both old trees and young ash saplings. In young plantations, other tree species (Sophora japonica, Gleditsia triacanthos) were also affected. Imaginal activity of Cicada orni was recorded in July and August, and the peak of egg hatching occurred from early August to mid-September. The high number of Cicada orni necessitates the development of measures to control the pest in the FPFBs

Health status of the field protective forest belts in Dobrudzha – results from the monitoring carried out in 2022

In 2022, the health status of the field protective forest belts on the territory of the State Hunting Enterprise Balchik and State Forest Enterprises General Toshevo and Dobrich was monitored. The assessment of tree crown condition covered 7069.3 ha (66% of all field protective belts in Bulgaria). The results showed that 70% of monitored belts were in good condition, 23% - in moderate condition, and 7% - in poor condition. Since 2014 the area of the protective forest belts in poor condition has increased 2.6 times, and 76% of them were situated in Dobrudzha region. Ash belts – Fraxinus excelsior (66% of all belts) and Fraxinus americana (10%) were in the worst conditon. In ash belts a process of crown dieback, premature falling of leaves and drying of whole trees were observed. In individual ash belts, drying reached up to 80% of tree crowns, regardless of their age and origin. The drying was mostly due to the biotic factors – insect pests and fungal pathogens. The protective forest belts of Quercus cerris, Q. petraea, Q., rubra and Gleditschia triacanthos stand out as sustainable tree species. It is necessary to significantly upgrade the methodology by which the monitoring of the health status of trees in the field protective forest belts is currently carried out. In the new methodology a detailed description of the type of data that need to be collected, the methods of assessments, and data reporting formats, have to be included

Role of the cultural ecosystem services provided by natural heritage in forest territories for sustainable regional development

The paper focuses on the role of the Natural Heritage in Forest Areas (NHFA) as a resource that can generate economic, social and environmental benefits for society through the provision of a wide range of cultural ecosystem services. In the assessment of the role of NHFA, the approach for assessment and mapping of ES in a given territorial scope was applied in a pilot region of Velingrad Municipality, focusing on the capacity of the forest ecosystems to provide cultural ecosystem benefits and services to the people. The study confirms that the identification of NHFA could be a powerful driver for regional development by creating significant positive effects such as improving sustainable cultural tourism in forests, diversifying forestry and supporting sustainable development and management of forest areas. The integration of the cultural services of NHFA into forest-related legislation can encourage job creation in different sectors and for different levels of employment, education and cultural training. Evaluation and mapping of ecosystem services is an appropriate tool to support the development of a concept and methods for assessing and mapping the general knowledge framework for NHFA policy in Bulgaria by applying an interdisciplinary approach

An Integrated Approach to Assess the Potential of Forest Areas for Therapy Services

The study considers forest therapy as a tool for diversification of forest management. An up-to-date integrated approach for assessing and mapping potential of forest areas which could provide conditions for forest therapy services is developed and tested. It is based on combining data from the traditional forest inventory in Bulgaria and other open databases with methods for integrated assessment and mapping of ecosystem services: 7 criteria groups and 22 indicators are proposed, rated on a 5-point scale. Overlay analysis is applied to generate a composite assessment for each forest unit. Using spatial statistics tools, territorial hot spots with potential for forest therapy are identified. The methodology was successfully tested in a pilot case-study region, Smolyan Municipality, but it is applicable at broader scale, regardless of the type and ownership of forests. This approach could be transferred to other countries as well after adapting to their geographical, geoecological and socio-cultural specifics and database available. It is a cost-effective and informative tool to support forest owners and managers to diversify forest welfare services focusing on insufficiently used forest recreation potential

Integrated approach for health status assessment of urban forests in the municipalities of Etropole and Pravets, Bulgaria

In 2020, the health status of urban forests in Etropole and Pravets municipalities was monitored based on remote sensing data and field assessment. The study provides information for early detection and identification of pests and pathogens causing damage in different forest types. Three forest stands were assessed: Scots pine (Pinus sylvestris) plantation near the town of Etropole, European beech (Fagus sylvatica) natural stand near Etropole Monastery, and Quercus spp. coppice stands in ‘Nebesnite Pasbishta’ forest park near Osikovitsa village. In two sample plots (town of Etropole and Osikovitsa village), remote sensing data were obtained by a ‘Parrot Sequoia’ multispectral camera integrated with a specialized professional system eBee ‘Flying Wing’. Normalised difference vegetation index (NDVI) was assessed by digital mixing of imagery, captured in the red and near-infrared range. It was established that the Scots pine plantations were weakened, with NDVI values between 0.66 and 0.75. The oak stands in the area of Osikovitsa village were in better health condition (NDVI mainly 0.79-0.98). Symptoms of diseases and pest damage were found during the field verifications. Severe deterioration caused by the invasive fungal pathogen Dothistroma septosporum had destroyed the pine plantation near Etropole. The pathogen caused premature needle defoliation, resulting in loss of timber yield and, in severe cases, tree death. In oak stands, damage was caused mainly by the invasive insect pest – oak lace bug (Corythucha arcuata). In Fagus sylvatica forests damage was caused mainly by abiotic factors (snow and wind), and wood destroying fungus Fomes fomentarius

An Integrated Approach to Assess the Potential of Forest Areas for Therapy Services

The study considers forest therapy as a tool for diversification of forest management. An up-to-date integrated approach for assessing and mapping potential of forest areas which could provide conditions for forest therapy services is developed and tested. It is based on combining data from the traditional forest inventory in Bulgaria and other open databases with methods for integrated assessment and mapping of ecosystem services: 7 criteria groups and 22 indicators are proposed, rated on a 5-point scale. Overlay analysis is applied to generate a composite assessment for each forest unit. Using spatial statistics tools, territorial hot spots with potential for forest therapy are identified. The methodology was successfully tested in a pilot case-study region, Smolyan Municipality, but it is applicable at broader scale, regardless of the type and ownership of forests. This approach could be transferred to other countries as well after adapting to their geographical, geoecological and socio-cultural specifics and database available. It is a cost-effective and informative tool to support forest owners and managers to diversify forest welfare services focusing on insufficiently used forest recreation potential

A methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria

Natural heritage (NH) includes natural features that can be described as outstanding universal value at a national level. It refers to the importance of ecosystems, biodiversity, and geodiversity for their existence value, and the ecosystems can be considered as the spatial units for its mapping and assessment. The ecosystem services (ES) concept provides an appropriate basis in the form of assessment and mapping methods that enable linking the state of ecosystems with human well-being. Thus, it can be used as a platform to find solutions to the problems related to the conflicts between conservation and the use of the NH. In this paper, we aim to present the process of developing a methodological framework for mapping and assessment of ecosystem services provided by the natural heritage in Bulgaria for recreation and tourism. The conceptual framework of the ecosystem-based assessment of NH in Bulgaria is based on the assumption that the generation of NH for the needs of tourism can be presented as the linkages between the natural systems and tourism in the form of ES potential, flow, and demand. The results demonstrate that the NH can be presented as a spatial phenomenon conceptualized by the flows of benefits from ecosystems to people which contribute to human well-being. The mapping and assessment procedures are fully developed for application at a national level, while for the regional and local level, few pilot studies mark some basic foundations for further development