scholarly journals Vegetation changes in beech and spruce stands in the Orlické hory Mts. in 1951–2001

2012 ◽  
Vol 49 (No. 10) ◽  
pp. 445-473 ◽  
Author(s):  
S. Vacek ◽  
K. Matějka
Keyword(s):  
Species Diversity ◽  
Species Number ◽  
Vegetation Changes ◽  
Developmental Trend ◽  
Herb Layer ◽  
Point Scale ◽  
Number Of Species ◽  
Beech Stand ◽  
Spruce Stands ◽  
Very High

Plant cenological surveys on the basis of Braun-Blanquet’s seven-point scale were made on 34 research plots in the course of studies of vegetation changes in beech and spruce stands in the Orlické hory Mts. over period of 1951–2001. The acquired data were processed not only by traditional plant coenological methods but also by numerical analyses (agglomerative and divisive classification, ordination, species diversity). The results document marked changes that occurred in species-rich spruce communities of the association Athyrio alpestre-Piceetum (Aa-P) as well as in species-poorer communities of the associations Vaccinio myrtilli-Piceetum (Vm-P), Calamagrostio villosae-Piceetum (Cv-P) and Deschampsio flexuosae-Piceetum (Df-P). The developmental trend of these communities in 1971–1991 converged on types very poor in species (Df-P association). On the contrary, the period 1991–2001 was characterised by a marked increase in the number of species, especially in the herb layer. An increase in coverage and number of tree species seedlings was very high after the productive seed years 1992 and 1995. The acceleration of changes in beech stands in 1971–1991 led to a species number diminution in herb-rich types of the association Dentario enneaphylli-Fagetum (De-F), and/or to their transition to species-poorer acidophilous types Calamagrostio villosae-Fagetum (Cv-F). Similarly like in spruce stands the number of species in beech stand relevés increased in 1991–2001. But a majority of typical species of herb-rich beech stands returned to the communities under study very slowly.

scholarly journals Spruce monocultures of the Drahanská vrchovina Upland (Czech Republic) as the biotope of small terrestrial mammals (Rodentia, Soricomorpha)

2010 ◽  
Vol 58 (2) ◽  
pp. 185-194 ◽  
Author(s):  
Josef Suchomel ◽  
Luboš Purchart ◽  
Jakub Urban
Keyword(s):  
Diversity Index ◽  
Abies Alba ◽  
Community Diversity ◽  
Myodes Glareolus ◽  
Herb Layer ◽  
Apodemus Flavicollis ◽  
Mixed Stands ◽  
Terrestrial Mammals ◽  
Beech Stand ◽  
Spruce Stands

The community of small terrestrial mammals of spruce monocultures of the Drahanská vrchovina Upland was studied on small experimental plots, namely in spruce plantations aged 30 and 105 years and on comparative plots in a 40-year beech stand and in a 125-year mixed stand occurring apart in the middle of spruce stands. In total, 128 small mammals of five species were trapped in the period 2006–2008. There were the marked dominance and abundance of Apodemus flavicollis at all plots (D = 67.7–82.1%; rA = 1.0–1.6) with the exception of a young spruce stand where Myodes glareolus (D = 57.5%; rA = 1.28) dominated. The community diversity was low (H' = 0.6–1.0) and rather balanced E = 0.51–0.89) showing the highest diversity index in a mature spruce monoculture, which, through its age (105 years), made possible the occurrence of a herb layer. With plantings of Abies alba and Fagus sylvatica (age 8 years), it provided the highest diversity of sites. The mixed and beech stands showed the lowest diversity (H' = 0.6–0.8), which was also affected by the extreme dominance of Apodemus flavicollis (73–82%). These biotopes represented optimum sites for this mouse. Differences in diversity, equitability and relative abundance between particular species and sites were not significant (p > 0.05). In general, the studied spruce stands appear to be little suitable sites for small terrestrial mammals. The local broadleaved and mixed stands established within the spruce monoculture transformation to close-to nature forests enable only increasing the dominance of adaptable species living in neighbouring spruce stands.

scholarly journals Vegetation Dynamic Assessment by NDVI and Field Observations for Sustainability of China’s Wulagai River Basin

2021 ◽  
Vol 18 (5) ◽  
pp. 2528
Author(s):  
Panpan Chen ◽  
Huamin Liu ◽  
Zongming Wang ◽  
Dehua Mao ◽  
Cunzhu Liang ◽  
...  
Keyword(s):  
Species Diversity ◽  
River Basin ◽  
Vegetation Change ◽  
Vegetation Index ◽  
Dynamic Assessment ◽  
Indicator System ◽  
Vegetation Changes ◽  
Vegetation Dynamic ◽  
Management Policies ◽  
The Impact

Accurate monitoring of grassland vegetation dynamics is essential for ecosystem restoration and the implementation of integrated management policies. A lack of information on vegetation changes in the Wulagai River Basin restricts regional development. Therefore, in this study, we integrated remote sensing, meteorological, and field plant community survey data in order to characterize vegetation and ecosystem changes from 1997 to 2018. The residual trend (RESTREND) method was utilized to detect vegetation changes caused by human factors, as well as to evaluate the impact of the management of pastures. Our results reveal that the normalized difference vegetation index (NDVI) of each examined ecosystem type showed an increasing trend, in which anthropogenic impact was the primary driving force of vegetation change. Our field survey confirmed that the meadow steppe ecosystem increased in species diversity and aboveground biomass; however, the typical steppe and riparian wet meadow ecosystems experienced species diversity and biomass degradation, therefore suggesting that an increase in NDVI may not directly reflect ecosystem improvement. Selecting an optimal indicator or indicator system is necessary in order to formulate reasonable grassland management policies for increasing the sustainability of grassland ecosystems.

Listening comprehension, shadowing and simultaneous interpretation of two ‘non-standard’ English speeches

Interpreting ◽  
2000 ◽  
Vol 5 (1) ◽  
pp. 25-48 ◽  
Author(s):  
Elisabetta Sabatini
Keyword(s):  
Listening Comprehension ◽  
Native Speakers ◽  
Standard English ◽  
Point Scale ◽  
Simultaneous Interpretation ◽  
Simultaneous Interpreting ◽  
Scale Scores ◽  
Low Performance ◽  
Working Hypotheses ◽  
Very High

Ten final-year interpreting students, all native speakers of Italian, were asked to perform three tasks using two ‘non-standard’ English speeches, one by an Indian speaking English as a second language (speaker A), and one by an American speaking English as a native language with a strong accent (speaker B). The duration of each speech was about 11 minutes, of which a different section was used for each task. First, subjects listened to the initial part of each speech (about 3 minutes) and were tested for listening comprehension. They then shadowed part of the speeches (about 2 minutes), after which they simultaneously interpreted the remainder from English into Italian. The working hypotheses were that: (i) the three tasks involve an increasing level of complexity: listening comprehension being the simplest and simultaneous interpretation the most difficult; (ii) ‘non-standard’ language in the source speech is a potential problem trigger for the interpreter. Performance in the three tasks was evaluated by examining the subjects’ answers to questions in the listening comprehension task (the highest score possible being 12), and by transcribing the shadowing and the simultaneous interpretation (both scored on a 12 point scale). In addition, subjects’ handling of previously identified problem areas in each simultaneous interpreting task was evaluated, again on a 12 point scale. Scores for each task were divided into bands, to distinguish between ‘very high’, ‘high’, ‘low’, and ‘very low’. Performance in the three exercises partly reflected their growing complexity, listening comprehension being the simplest and simultaneous interpretation the most difficult. The non standard characteristics of the two speeches were indeed difficult for some of the subjects to interpret. Taking Gile’s Effort Model as a theoretical basis, the study also provides some insight as to which phase of simultaneous interpretation caused most difficulties.

Temporal patterns in the macrobenthic communities of the Hawkesbury estuary, New South Wales

1987 ◽  
Vol 38 (5) ◽  
pp. 607
Author(s):  
AR Jones
Keyword(s):  
Community Composition ◽  
Temporal Patterns ◽  
Single Species ◽  
Species Number ◽  
Community Patterns ◽  
Low Salinity ◽  
Number Of Species ◽  
South Wales ◽  
Physicochemical Factors ◽  
Number Of Individuals

Temporal patterns in number of species, number of individual animals and community composition of the soft-sediment zoobenthos of the Hawkesbury estuary are described and related to physicochemical factors. Replicate grabs were taken at 3-month intervals over 3 years (1977-1979) from sites located in three zones: the lower, middle and upper reaches. The number of species and number of individuals showed significant seasonal and annual differences in all zones. However, the pattern of these differences varied among sites and seasonal differences were not repeatable over years. Similarly, differences in community composition as revealed by classification were not seasonal. In the middle and lower reaches, these differences were apparently caused by the over- riding influence of non-seasonal climatic events, i.e. a major flood in 1978 and a drought throughout 1979. In the first two sampling following the flood, sample values for the numbers of both species and individuals were usually lowest and community composition was distinct from pre-flood and drought times. During the drought, the number of species was usually high and community composition relatively distinct. Whereas the number of species and community composition groupings were both significantly related to river discharge, the number of individuals was significantly correlated with temperature. All community variables were sometimes significantly related to salinity. The identity of numerically dominant species, as determined by Fager rankings, varied among times in both the lower and middle reaches. However, the polychaete Nephtys australiensis and the bivalve mollusc Notospisula trigonella were highest ranked overall in both zones. Community patterns in the low-salinity upper reaches differed from those further downstream by showing little change in numbers of species and community composition following the flood. Only the number of species was significantly correlated with any of the measured physicochemical variables, this being partly due to an influx of species during the drought. Furthermore, the upstream community was always dominated by the polychaete Ceratonereis limnetica and was thus the only community that could be characterised by a single species.

Effect of Artificial Grassland Establishing on the Vegetation Restoration in the Degraded Ecosystem

2014 ◽  
Vol 955-959 ◽  
pp. 3474-3478
Author(s):  
Tie Jun Sun
Keyword(s):  
Species Diversity ◽  
Community Composition ◽  
Early Period ◽  
Vegetation Restoration ◽  
Bromus Inermis ◽  
Perennial Grasses ◽  
Species Number ◽  
Composition And Structure ◽  
Degraded Ecosystem ◽  
Annual Grasses

Experiment was executed to plant Bromus inermis artificially in the degraded ecosystem, and study effect of grass planting on vegetation restoration. The results indicated that natural vegetation restored rapidly in the degraded ecosystem in two years after grass planted. But species diversity changed little in the early period of vegetation restoration, while vegetation biomass, coverage and anti-interference improved quickly. In addition, species number and important value of perennial grasses increased while those of annual grasses decreased. Then community composition with annual plants mainly changed gradually into that with perennial plants mainly after Bromus inermis planted. However, overground biomass and coverage of restored vegetation and dominance of Bromus inermis planted decreased after vegetation cut once a year. And species diversity and important value of annual grasses increased. Thus it could be good for uniformity of species distribution and stability of community composition and structure to develop.

Tree density, basal area and species diversity in a disturbed dry tropical forest of northern India: implications for conservation

2006 ◽  
Vol 33 (3) ◽  
pp. 256-262 ◽  
Author(s):  
R. SAGAR ◽  
J.S. SINGH
Keyword(s):  
Species Diversity ◽  
Tropical Forest ◽  
Basal Area ◽  
Tree Density ◽  
Dry Forest ◽  
Conservation Strategies ◽  
Stem Density ◽  
Dry Tropical Forest ◽  
Number Of Species ◽  
Northern India

Dry tropical forest communities are among the world's most threatened systems and urgent measures are required to protect and restore them in degraded landscapes. For planning conservation strategies, there is a need to determine the few essential measurable properties, such as number of species and basal area, that best describe the dry forest vegetation and its environment, and to document quantitative relationships among them. This paper examines the relationships between forest basal area and diversity components (number of species and evenness) for a disturbed dry tropical forest of northern India. Data were collected from five sites located in the Vindhyan dry tropical forest of India, selected on the basis of satellite images and field observations to represent the entire range of conditions in terms of canopy cover and disturbance regimes. These sites represented different communities in terms of species composition. The forest was poorer in species richness, and lower in stem density and basal area than wet forests of the tropics. Across sites (communities), the diversity components and tree density were positively related with total tree basal area. Considering basal area as a surrogate of biomass and net production, diversity is found to be positively associated with productivity. A positive relationship between basal area, tree density and species diversity may be an important characteristic of the dry forest, where recurring disturbance does not permit concentration of biomass or stems in only a few strong competitors. However, the relationships of basal area with density, alpha diversity and evenness remain statistically significant only when data from all sites, including the extremely disturbed one, are used in the analysis. In some sites there was a greater coefficient of variation (CV) of basal area than in others, attributed to patchy distribution of stems and resultant blanks. Therefore, to enhance the tree diversity of these forests, the variability in tree basal area must be reduced by regulating local disturbances. Conservation activities, particularly fuelwood plantations near human settlements, deferred grazing and canopy enrichment through multi-species plantations of nursery-raised or wild-collected seedlings of desirable species within the forest patches of low basal area, will be needed to attain restoration goals, but reforestation programmes will have to be made attractive to the forest-dwelling communities.

Chalcidoidea of Iran (Insecta: Hymenoptera)

2021 ◽  
Keyword(s):  
Biological Control ◽  
Species Diversity ◽  
Phylogenetic Relationships ◽  
Parasitoid Species ◽  
Number Of Species ◽  
The Family ◽  
Differential Characters ◽  
Biological Attributes

Abstract Within Hymenoptera, the superfamily Chalcidoidea (chalcidoid wasps) is the second largest superfamily after Ichneumonoidea. Because of the preponderance of parasitoid species, Chalcidoidea is one of the most important groups in applied biological control. This book provides a comprehensive, accurate checklists for the chalcidoid fauna of Iran. The species listed in each family chapter include all the species recorded in the literature from Iran through 2019, with one exception as noted in Chapter 10 (Eurytomidae). Each family chapter includes differential characters to distinguish the family, hypothesized phylogenetic relationships with other families, and general biological attributes of the family. Previous cataloguing efforts of the Iranian fauna for the family are summarized, as well as the information included in the checklist of species for the family. This summary information includes the number of species recorded from Iran, any newly recorded species, a comparison of the Iranian fauna with those of adjacent countries, and major host attributes of the family in Iran. Also included for each species record are host records and plant associates in Iran, when known, and additional comments as necessary. The final chapter tabulates the species diversity of Iranian Chalcidoidea by family, the species newly exclude from Iran, the species presently considered as endemic to Iran and the number of species of each family that are known from each of the 31 provinces that comprise Iran. Because of the importance of chalcidoids for biological control of pests in Iran, host information for parasitoid species that is provided throughout the chapters is synthesized in an Appendix at the end of the book.

Diversity of Iranian Chalcidoidea.

2021 ◽  
pp. 399-410
Author(s):  
Hassan Ghahari ◽  
Gary A. P. Gibson ◽  
Gennaro Viggiani
Keyword(s):  
Saudi Arabia ◽  
Species Diversity ◽  
United Arab Emirates ◽  
Economic Issues ◽  
Number Of Species ◽  
Pest Insects ◽  
Former Ussr

Abstract This chapter tabulates the species diversity of Iranian Chalcidoidea by family, the species newly exclude from Iran, the species presently considered as endemic to Iran and the number of species of each family that are known from each of the 31 provinces that comprise Iran. It also tabulates the fauna of Iran compared with those of 15 adjacent countries having land and sea borders with Iran: Afghanistan, Armenia, Azerbaijan, Bahrain, Iraq, Kazakhstan, Kuwait, Oman, Pakistan, Qatar, Russia, Saudi Arabia, Turkey, Turkmenistan and United Arab Emirates, as well as the former USSR. Finally, comments are provided concerning the importance of accurate taxonomy and species checklists to help resolve economic issues resulting from agricultural and forestry pest insects.

scholarly journals Transformation of even-aged spruce stands at the School Forest Enterprise Kostelec nad Černými lesy: Structure and final cutting of mature stand

2012 ◽  
Vol 52 (No. 4) ◽  
pp. 158-171 ◽  
Author(s):  
J. Remeš
Keyword(s):  
Forest Stand ◽  
Growth Potential ◽  
Main Criterion ◽  
Individual Tree ◽  
Main Method ◽  
Single Tree ◽  
Mature Stand ◽  
Spruce Stands ◽  
Individual Trees ◽  
Very High

This paper deals with the transformation of pure even-aged forest stands to mixed and more uneven-aged stands on an example of selected even-aged Norway spruce stands in the School Forest Enterprise (SFE) in Kostelec nad Černými lesy. A forest stand where individual tree felling was used as the main method of forest stand regeneration was chosen as a conversion example. The main criterion of tree maturity is the culmination of mean volume increment of a single tree. The analyses confirmed a very high variability in the growth potential of individual trees. The potential and actual increment was strongly influenced by the stand position of tree and by crown release. These results show a high potential level of tree growth even at the age of 120 years. From 30% to 9% of all trees on particular experimental plots achieved felling maturity.

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