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This study discovers the distribution of vegetation in the Sougna Mountain and its modern pollen representation and investigates the relationships with environment and land use variables. A total of 31 moss polsters were collected between 138 and 1364 m above sea-level from wooded to open areas (e.g. cork oak forest, pine reforestation, and shrubland). At each sampling site land use and environment variables were collected. The vegetation in the Sougna Mountain is scattered in a mosaic along three vegetation belts which are displayed in distinct pollen assemblages dominated by the pollen equivalents of the vegetation types (Quercus suber forest, matorrals of Erica spp. and Cistus spp. and Pinus pinaster reforestation). The variation between the variables and pollen data was performed using CCA analysis. The anthropogenic variables such as grazing, and cultivation, contribute to discrimination of the degraded and grazed areas. High precipitation and altitude have a rather good correlation to wooded communities and consequently a good relation to the tree cover. Our results show that the pollen types of Poaceae, Cannabis, Plantago, Nicotiana, Asteraceae, and Urtica are related mostly to human practice and distinguish the disrupted communities. The presence of those taxa in the pollen diagram must be interpreted carefully. A high taxonomic resolution is recommended to prevent the overestimation of the abundance of some taxa. Our results contribute to the advancement of palynological reconstructions of past vegetation and land use in Sougna Mountain and generally in the Rif landscape. [ABSTRACT FROM AUTHOR]

Abstract Background Soil microorganisms are in constant interaction with plants, and these interactions shape the composition of soil bacterial communities by modifying their environment. However, little is known about the relationship between microorganisms and native plants present in extreme environments that are not affected by human intervention. Using high-throughput sequencing in combination with random forest and co-occurrence network analyses, we compared soil bacterial communities inhabiting the rhizosphere surrounding soil (RSS) and the corresponding bulk soil (BS) of 21 native plant species organized into three vegetation belts along the altitudinal gradient (2400–4500 m a.s.l.) of the Talabre–Lejía transect (TLT) in the slopes of the Andes in the Atacama Desert. We assessed how each plant community influenced the taxa, potential functions, and ecological interactions of the soil bacterial communities in this extreme natural ecosystem. We tested the ability of the stress gradient hypothesis, which predicts that positive species interactions become increasingly important as stressful conditions increase, to explain the interactions among members of TLT soil microbial communities. Results Our comparison of RSS and BS compartments along the TLT provided evidence of plant-specific microbial community composition in the RSS and showed that bacterial communities modify their ecological interactions, in particular, their positive:negative connection ratios in the presence of plant roots at each vegetation belt. We also identified the taxa driving the transition of the BS to the RSS, which appear to be indicators of key host-microbial relationships in the rhizosphere of plants in response to different abiotic conditions. Finally, the potential functions of the bacterial communities also diverge between the BS and the RSS compartments, particularly in the extreme and harshest belts of the TLT. Conclusions In this study, we identified taxa of bacterial communities that establish species-specific relationships with native plants and showed that over a gradient of changing abiotic conditions, these relationships may also be plant community specific. These findings also reveal that the interactions among members of the soil microbial communities do not support the stress gradient hypothesis. However, through the RSS compartment, each plant community appears to moderate the abiotic stress gradient and increase the efficiency of the soil microbial community, suggesting that positive interactions may be context dependent.

Background: Soil microorganisms are in constant interaction with plants, and these interactions shape the composition of soil bacterial communities by modifying their environment. However, little is known about the relationship between microorganisms and native plants present in extreme environments that are not affected by human intervention. Using high-throughput sequencing in combination with random forest and co-occurrence network analyses, we compared soil bacterial communities inhabiting the rhizosphere surrounding soil (RSS) and the corresponding bulk soil (BS) of 21 native plant species organized into three vegetation belts along the altitudinal gradient (2400–4500 m a.s.l.) of the Talabre–Lejía transect (TLT) in the slopes of the Andes in the Atacama Desert. We assessed how each plant community influenced the taxa, potential functions, and ecological interactions of the soil bacterial communities in this extreme natural ecosystem. We tested the ability of the stress gradient hypothesis, which predicts that positive species interactions become increasingly important as stressful conditions increase, to explain the interactions among members of TLT soil microbial communities. Results: Our comparison of RSS and BS compartments along the TLT provided evidence of plant-specific microbial community composition in the RSS and showed that bacterial communities modify their ecological interactions, in particular, their positive:negative connection ratios in the presence of plant roots at each vegetation belt. We also identified the taxa driving the transition of the BS to the RSS, which appear to be indicators of key host-microbial relationships in the rhizosphere of plants in response to different abiotic conditions. Finally, the potential functions of the bacterial communities also diverge between the BS and the RSS compartments, particularly in the extreme and harshest belts of the TLT. Conclusions: In this study, we identified taxa of bacterial communities that establish species-specific relationships with native plants and showed that over a gradient of changing abiotic conditions, these relationships may also be plant community specific. These findings also reveal that the interactions among members of the soil microbial communities do not support the stress gradient hypothesis. However, through the RSS compartment, each plant community appears to moderate the abiotic stress gradient and increase the efficiency of the soil microbial community, suggesting that positive interactions may be context dependent. [ABSTRACT FROM AUTHOR]

Involving of new territories not used before into different industry forms including construction of boreholes for gas exploring requires detailed revealing and comprehensive analysis of physical-geographic and environmental conditions of concrete territories. It concerns especially easily destroyable components of biota (a biome) such as vegetation cover. Underestimation of the specifics of structural-dynamic organization of phytocoenoses in concrete ecotopes can result in the destruction of vegetation up to its complete decay. Using one of gas-bearing area in Irkutsk Region, we tried to make possible characteristics of vegetation spatial stratigraphy and its responses to some impacts while constructing boring holes under existing environmental conditions. [ABSTRACT FROM AUTHOR]

According to the the biome concept, the idea of the orobiome and its significance in the evaluation of the biodiversity for mountain territories are disclosed. Altitudinal gradients of vegetation with certain altitudinal limits of development are the basis for analysing the floristic and coenotic diversity of the orobiome and the ecological and geographical patterns of its spatial organization at the regional level. Based on the example from Kodar-Kalar orobiome, an altitudinal composition of the vegetation of the Northern Transbaikalia has been identified using thematic maps. The statistical evaluation of the altitudinal distribution of 4 vegetation belts (the upper tundra belt, the tundra belt, the sub-tundra belt and the mountain taiga belt) has been made. The regional features of the altitude position of the basic vegetation types forming the belts have been determined for the orobiome. They are reflected in three geographical variants. Orographic conditions and the history of the territory development have been discussed in the analysis of regional features of altitudinal spectra difference.

The eruption of Anak Krakatoa Volcano is assumed to be the cause to generate tsunami wave; it can also be assumed that the wave source is only about 50.3 km from the coast. The interesting point is that the propagation of the tsunami wave was not caused by an earthquake but rather by volcanic material from Anak Krakatoa Volcano which slid into the sea. An investigation was conducted using spatial analysis of coastal areas around Tanjung Lesung, Banten with GIS analysis. While the propagation of tsunami waves was calculated from Anak Krakatoa Volcano that was projected towards Tanjung Lesung, Banten. These analyses were done to obtain assumptions of the wave velocity and propagation time from the center of the wave to the coastal area. The primary purpose of this study is to investigate the effectiveness of the vegetation belts as tsunami mitigation. This study used a 2D numerical simulation wave based on a VOF method. The numerical simulation calculated the interaction between the bore wave propagation and the vegetation belts. Numerical analysis was done to estimate the altitude and velocity of tsunami waves toward the coastal area of Tanjung Lesung. By comparing the results of the spatial and numerical analysis, the delineation of the tsunami-affected area on 31 December 2018 can be determined. [ABSTRACT FROM AUTHOR]

During the past few decades, urban areas have experienced increasing environmental stress. Noise is considered as one of the most important sources of urban pollution with adverse effects on human health. Urban vegetation provides many ecosystem services including the reduction of noise pollution. Hedges are widespread in cities and have the peculiarity of being often grown close to the source of noise. The study investigated the noise reduction due to hedges of Prunus laurocerasus and Laurus nobilis and the effect of the vegetation on sound spectra. Four different trials were carried out, including the use of two different noise sources and the measurement of noise at different distances both from the green barrier and from the noise source. During one trial, the influence of the type of ground surfaces between the noise source and the receiver was also evaluated. In the three trials where a significant attenuation of the noise occurred, the porosity of hedges measured less than 4.6% and an average noise reduction of about 2.7 dB(A) (max 7.0 dB(A)) was observed. This effect was particularly relevant in the range of higher frequencies (between 2 and 20 kHz). This study can contribute to plan and design hedges in the urban context.

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The study analyses the relationship between the distribution of the main Italian forest vegetation types and the conditions during average temperature of the coldest month, at present and those predicted for scenarios A2a and B2a of the GCM HADCM3 until the year 2080. With an increased average temperature of the coldest month up to 4.4 °C in 2080, current temperature values for the main forest species will change greatly, creating favorable preconditions for an increased presence of broadleaved deciduous species in mountain altitudes of the Alps, more termophilous broadleaved species on those of the Appennines and more Mediterranean species on lower mountains, hills and lowlands of the country. The results are compared with previsional models of tree species distribution due to predicted climate changes, and the possible influence of some ecological factors is discussed.

Para completar estudios de vegetación de la vertiente oriental del Cordón del Plata, se analizaron las comunidades vegetales de sitios húmedos de vegas. Se determinaron dos tipos de vegas: de baja altura, entre los 1200- 2000 m s.m. y de altura, por encima de los 2000 m s.m. representadas por 9 y 11 comunidades respectivamente. Estas se describieron fisonómica, florística y ecológicamente. Se establecieron relaciones de distribuciones de las vegas entre altitudes y temperaturas, involucrando también a procesos de congelamiento de los suelos. Además, se consideraron aspectos biológicos, de origen y corológica de las especies. En coincidencia con los pisos de vegetación del área sobre las vegas de altura se reconocen tentativamente una de mediana altura distribuída entre los 2000 a 3200 m s. m. y una de tundra que no fue considerada en este trabajo , por encima de 3200 m s.m.. Se elaboró un mapa de localización de las vegas del área de estudio.In this study I present a description of the plant communities of humid sites of vegas or mallines of the eastern slope of the Cordón del Plata were analyzed. Two types of vegas were identified: 1) low altitude vegas between 1200- 2000 m a.s.l. represented by 9 communities; and 2) high altitude vegas above 2000 m a.s.l. represented by 11 communities. These communities were described through their physiognomy, floristic composition, and ecology. In order to analize the distribution of the vegas, relationships were drawn among altitude, temperature, and soil freezing processes. In addition, biological and chorological characteristics of the species, as well as their origins were considered. With respect to the vegetation distribution, high-altitude vegas occur at a intermediate altitudes between 2000 and 3,200 meters above sea level, and tundra (which was not considered as part of the study) occurs above 3,200 meter above sea level. A map was produced of the location of the area's wetlands.

The Beskid Niski Mts. and the foothill area of the Carpathians are under-represented in pollen data due to the unfavorable conditions for peat formation. This contribution is a review supplemented by new palaeobotanical data dedicated to the late Holocene history of local forests. Pollen, wood and other plant macrofossils as well as a new approach to isopollen mapping were used to reconstruct the migration of late-successional trees between ca. 3500 and 1900 BC. This time interval was define as a critical period in the development of the modern vegetation belts. We documented a quite late arrival of hornbeam, ca. 3500 BC, from the south and south east as well as optimal development of oak-lime-hornbeam forests forming the foothill belt between 2600 and 1600 BC. The migration of beech occurred ca. 3250–2750 BC and was followed by fir ca. 2800–2500 BC. Beech-fir forests already developed c. 2500 BC, and became common since ca. 1850 BC in the lower montane belt. On a regional scale, transformation of vegetation coincided with phases of climate moistening. The auxiliary role of the Corded Ware culture settlement, exploiting for the first time the upper landscape zone in the Carpathians, in the establishment of the new types of woodland, was indicated. Local differences in permanent deforestation of extensive areas were also analyzed. The beginning of this process in the lower landscape zone took place in the Roman Iron Age or in the Early Medieval time. In the upper landscape zone, it occurred in the Late Medieval or modern times, particularly as a result of the Wallachian colonization in the 15th and 16th century AD. [ABSTRACT FROM AUTHOR]

This paper reviews ways of reducing surface transport noise by natural means. The noise abatement solutions of interest can be easily (visually) incorporated in the landscape or help with greening the (sub)urban environment. They include vegetated surfaces (applied to faces or tops of noise walls and on buildings’ façades and roofs), caged piles of stones (gabions), vegetation belts (tree belts, shrub zones and hedges), earth berms and various ways of exploiting ground-surface-related effects. The ideas presented in this overview have been tested in the laboratory and/or numerically evaluated in order to assess or enhance the noise abatement they could provide. Some in-situ experiments are discussed as well. When well designed, such natural devices have the potential to abate surface transport noise, possibly by complementing and sometimes improving common (non-natural) noise reducing devices or measures. Their applicability strongly depends on the available space reserved for the noise abatement and the receiver position. [ABSTRACT FROM AUTHOR]

Forest vegetation in view of some scenarios of climate change in Italy. The study analyses the relationship between the distribution of the main Italian forest vegetation types and the conditions during average temperature of the coldest month, at present and those predicted for scenarios A2a and B2a of the GCM HADCM3 until the year 2080. With an increased average temperature of the coldest month up to 4.4 °C in 2080, current temperature values for the main forest species will change greatly, creating favorable preconditions for an increased presence of broadleaved deciduous species in mountain altitudes of the Alps, more termophilous broadleaved species on those of the Appennines and more Mediterranean species on lower mountains, hills and lowlands of the country. The results are compared with previsional models of tree species distribution due to predicted climate changes, and the possible influence of some ecological factors is discussed. [ABSTRACT FROM AUTHOR]

Abstract: This article presents the floristic, structural, and syntaxonomical features of plant assemblages in temporary wetlands and the pattern of the corresponding habitat types; according to the Habitats Directive. Nine pristine temporary wetlands covering a wide range of shapes, elevations and substrates were monitored. The “within temporary wetlands” hydrological gradient was strong enough to drive the vegetation and habitat type patterns. Plant assemblages presented a spatial arrangement in three concentric belts repeatedly present in each site in the same relative position. The presence of the H3120 habitat type was recognized in the central and in the intermediate belt. The outer belt was the more suitable for the presence of the H3170* priority habitat. Therefore, it should represent the main conservation target within temporary wetlands. On the other hand, it was the smallest in size (only 13% of the total surface) and in some cases absent, inconspicuous, or severely fragmented. [Copyright &y& Elsevier]

Modern proxy-calibration studies are a powerful tool for paleoecological interpretation. This paper analyzes the relationships among modern pollen rain, vegetation and altitude in the central Pyrenees, where several paleo-palynological studies have been developed, but a modern analog survey is still unavailable. The work analyzes the pollen content of moss polsters from different vegetation communities along an altitudinal transect, as well as the flora and vegetation using the Braun-Blanquet system. DCCA showed that altitude satisfactorily explains both vegetation (r2 = 0.988) and pollen (r2 = 0.841) gradients. Besides the complexity of pollen-vegetation relationships, some regularities were found to be useful for paleoecological and paleoenvironmental interpretation. In general, altitudinal vegetation and pollen patterns show similarities, but pollen belts and boundaries are less well defined, likely because of the homogenizing effect of upward wind transport. Palynological differentiation of montane from subalpine/alpine belts is straightforward from the trends of the more significant pollen types, mainly the low-altitude deciduous trees and the high-mountain herbs. Palynological differences between subalpine and alpine belts, which boundary coincides with the treeline, are more subtle and need quantitative criteria and complementary proxies. From an individual point of view, four main groups of pollen were distinguished, in relation to their usefulness as vegetation and altitudinal indicators: (1) very good indicators, (2) good indicators, (3) non indicators, and (4) allochthonous pollen types. The first two groups resulted to be useful as indicator taxa for modern analogs for paleovegetational and paleoaltitudinal reconstruction, while the latter two groups should be interpreted with caution in paleoenvironmental studies. [ABSTRACT FROM AUTHOR]

Abstract: Traffic noise attenuation at different 1/3-octave frequencies is measured at three vegetation sites and a control site in Delhi, the capital city of India. The study indicates that attenuation generally increases with frequency. At low frequencies, maxima (between 10 and 16dB) in relative attenuation are observed in the frequency interval between 315 and 400Hz. Comparatively greater relative attenuation (>20dB) is observed in the high frequency range between 10 and 12.5kHz. A significantly higher relative attenuation of more than 24dB is observed characteristically at 3.15kHz at all the vegetation sites. The results indicate that vegetation belts could be used as effective barriers for traffic noise control along the roadsides. [Copyright &y& Elsevier]

Deforestation and fragmentation are threats to the conservation of species and have consequences for ecosystem functions. The focus of this study was to elucidate forest cover change in the period of 1993 to 2014. Our study area is in the central region of Veracruz, Mexico. Land cover and land use classes for the Years 1993, 2000, and 2014 were derived from Landsat images applying supervised classification. Then, we quantified the net change in forest area, the loss of original forest area, and evaluated forest fragmentation using landscape metrics. Our results showed that the area covered by remnant forests decreased 57%. The annual net forest cover change rate for 1993 to 2000 was −0.44%; since then forest cover increased at a rate of 0.11% from 2000 to 2014. The decreasing total edge density and the mean proximity index during the entire period of the study indicate decreasing irregularity in the shape of remnant forest patches and a slight decrease of vulnerability to edge effects. Forest patches augmented in 2000 and decreased in 2014 demonstrating an 18% decrease in relation to the number of fragments existing in 1993. According to our study, this area demands an urgent attention on preservation initiatives because only 2% of the surface extent is below federal protection and 0.8% is under State protection. It is important to protect the larger forest areas left in the pine-oak and humid montane forest belt because of their importance to plant diversity conservation and particularly, as these are threatened by urban and agricultural expansion. [ABSTRACT FROM AUTHOR]