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Environment

Volume XV |

Volcanic Eruptions in South Europe and the Change of Carbon Dioxide Concentration – Case Study: “Moussala” Basic Environmental Observatory

Abstract: The volcanic eruptions are one of the most characteristic natural sources of CO2 in the atmosphere (IPCC, 1990, 2007). In order to study the effect of volcanic eruptions on the increased levels of CO2, we have used data from the Basic Environmental Observatory (BEO) “Moussala”, Bulgaria, for the period comprised between July 2007 and March 2015. The Carbon dioxide is not a health hazard gas and there is no established limit concentration by the Bulgarian and international law. In this study, we have accepted as extremely high values the values that exceed the 95th percentile of the distribution of the daily average values for the studied period. The days with exceeding CO2 concentration were analysed in terms of volcanic activity (Etna), which could affect the investigated area with the spread of air pollutants and also CO2. The simulations developed by the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) Model are used in order to describe the trajectory and dispersion of pollutant and products from eruptions of Etna in the atmosphere. A synchrony between the occurrence of days with extreme high concentration of CO2 in the atmosphere in the region of BEO “Moussala” and eruptions of Etna volcano was established in most of the investigated cases.
The analysis of the results from BEO “Moussala” confirms the impact of the volcanic eruptions and Etna volcano, in particular, for the increasing of CO2 concentration in the atmosphere. On the other side, it was established that the activity of Etna is not the only factor which has impact on the concentration of CO2. More detailed analyses concerning not only natural, but also anthropogenic factors have to be done in the future in order to clarify the reasons for the increasing concentration of CO2 in the atmosphere (IPCC, 2014).

Volume XV |

The Assessment of Artificial Water Surfaces Regeneration in Stachinez Swamps Protected Area by Using Remote Sensing and In–situ Data

Abstract: The Satchinez Swamps, a remnant of the swamps once specific for Banat Plain, is an ornithological reserve since 1942 and the habitat of many protected bird species. Draining works conducted in the seventies affected the reserve by decreasing the water surface area. Thirty-five years later, hydro-technical works aiming to restore the former aquatic surfaces within the buffer zone were conducted. Thus, in 2005 a water delivery canal from the discharge canal of Satchinez reservoir towards Balta Mare was built. The objective of this study is to assess the efficiency of the hydrological works carried out in 2005 by using temporal analysis of some normalized difference indexes derived from satellite images, in relation to precipitation data (recorded at Timisoara meteorological station) as an indicator for wetland restoration. We used geospatial data from different time periods: historical maps (1953, 1962 and 1984), orthophotos (1963, 1970, 2005 and 2012), oblique airphotos (2004) and 38 Landsat satellite scenes (1984-2015), two images per year, for the dry season respectively for the rainy season. We noticed a slight increase of the Normalized Difference Vegetation Index (NDVI) in Balta Mare and on the relict watercourse of Sicsău stream, which shows the expansion of reed and suggests an increase in soil moisture. During the dry season, for the period before the restoration works (1984 – 2004) there is a strong, very significant correlation between Normalized Difference Water Index (NDWI) and precipitations (r =0.7008, p = 0.0011). After 2005, this correlation no longer occurs (r = -0.1083, p <0.05), which demonstrates that precipitations are not the main water supply for Balta Mare anymore. For the 1984 – 2015 period, during rainy months the Modified Normalized Difference Water Index (MNDWI) indicate the presence of water in Balta Mare, but during the dry months, it demonstrates the lack of water which underlines the temporary character of this pond and confirms the field observations. We conclude that the restoration did not succeed in the rebuilding of the former water surfaces of Balta Mare, but has an effect in increasing the underground water level in this area followed by reed extension.

Volume XV |

Modelling of Ecosystem Indicators in Geographic Information System Environment (A Case Study of the Sweet Chestnut Forest, Belasitsa Mountain, Bulgaria)

Abstract: The aim of the present research is to show the possibilities of applying computer technology in ecosystem investigations. The object of the research is the chestnut forests located on the Northern slopes of Belasitsa mountain (Southwest Bulgaria). Three study areas are determined for detailed investigation of structural and functional parameters (indicators) of chestnut ecosystems. These areas are located in forests with different ages (45-120 years old), different forestry management and different state. Ecosystem indicators are modeled on the base of field investigation and available published data, and the assessment of the forest state is done by spatial interpolation (inverse distance weighted) in geographic information system (GIS) environment (ArcGIS). Resulting model values are verified and validated by field investigations. An output layer showing the state of the chestnut forest in the investigated region is generated on the base of the raster surfaces, result of the interpolation and application of map algebra. Also, weight coefficients to the assessment values of the different indicators are used which makes the spatial analysis more correct. Created mapping model shows significant matching areas of forests in poor condition and forests in good conditions compared to the relevant determined on the base of forest management plan. The research confirms the advantages of GIS technology in processing large and varied data for assessing the impact of many factors on forest vegetation.

Volume XV |

Derivation of ecological indicators for assessing landscape health and habitat disturbance in Lower Barpani watershed of Assam (India)

Abstract: Landscape health is a primary concern for management of resources and restoration of habitats of various fauna and avifauna in watershed. We derived landscape health index using Landsat Thematic Mapper satellite data of 1987 and 2011. Standard precipitation index, normalized difference water index, normalized difference moisture index, normalized difference barren land index, normalized difference vegetation index, human disturbance, height, slope, land use/ land cover were integrated to assess landscape health and habitat disturbance in Lower Barpani watershed in India. Landscape health was categorized into five groups, i.e. very good, good, moderate, poor and very poor.
Spatial-temporal variation of landscape health revealed that the area under very good health has degraded from 45% in 1987 to only 1% registering a decrease of 97.26%. The area under good, moderate, poor and very poor categories of landscape health experienced positive change. Habitat disturbance in forests and wetlands has also increased due to shifting agriculture, deforestation and cultivation in wetlands. Remotely sensed indices of landscape health and habitat disturbance can effectively be utilized for prioritizing ecological restoration across space at various scales.

Volume XIV |

The Human Pressure on the Environment Quality Through Land Use in Northern Side of the Someșean Plateau – Romania

Abstract: The analysed rural area has encountered, over the years, a series of economic, demographic and especially ecological changes, driven by the development of the society. Most of these changes had negative effects upon the environment. Human activities have also determined positive and negative topographic changes on the environment. The economic activities taking place in this rural area suffer from a lack of diversity and focus only on the usage of local resources, mainly agricultural and forestry. This is the main reason that caused the increase of the human impact upon the landscape and its components.
The current state of the quality of the environment and the changes it has suffered should have a significant importance for the rural community, so that one may issue some measures for protecting the ecosystems, for a sustainable development process to take place. The present study analyses the main human activities from the northern part of the Someșean Plateau in order to draw attention to the impact of human pressure on the quality of the environment.