scholarly journals Dynamics of the woody vegetation of two areas of Cerrado sensu stricto located on different substrates

Rodriguésia ◽  
2016 ◽  
Vol 67 (4) ◽  
pp. 859-870 ◽  
Author(s):  
Letícia Gomes ◽  
Leandro Maracahipes ◽  
Simone Matias Reis ◽  
Beatriz Schwantes Marimon ◽  
Ben Hur Marimon-Junior ◽  
...  
Keyword(s):  
Plant Community ◽  
Basal Area ◽  
Sensu Stricto ◽  
Conservation Strategies ◽  
Woody Vegetation ◽  
Dynamic Parameters ◽  
Differential Evaluation ◽  
Set Up ◽  
Effective Conservation ◽  
Over Time

Abstract Differences in substrates can provoke distinct responses in the dynamics of a plant community. We compared changes the floristic, structural and dynamic parameters of the woody vegetation between burned sites dominated by cerrado típico (CT) and cerrado rupestre (CR), which is characterized by the presence of rocky outcrops, over time. We set up 10 plots (20 m × 50 m) at each site. All individuals (diameter of ≥ 3 cm at 30 cm height above the ground) were identified in the two censuses (2009 and 2012) and measured (stem diameter), after an accidental fire in 2008. Changes in floristic parameters between the CT and CR were not significant. However, we found significant differences (p < 0.05) in structural and dynamic parameters, such as density (CT = 1,523; CR = 2,171 ind.ha-1), basal area (CT = 8.70; CR = 13.00 m2.ha-1), recruitment rates (CT = 24.35; CR = 15.14% year-1; p = 0.01), gain (CT = 8.58; CR= 3.58% year-1), and the loss rates of basal area (CT = 3.88; CR= 2.45% year-1). These differences emphasize the need for a differential evaluation of these sites for the development of effective conservation strategies.

scholarly journals Structure and floristic relationships between Cerrado sensu stricto sites on two types of substrate in northern Cerrado, Brazil

2013 ◽  
Vol 13 (4) ◽  
pp. 121-132 ◽  
Author(s):  
Helena Lara Lemos ◽  
José Roberto Rodrigues Pinto ◽  
Henrique Augusto Mews ◽  
Eddie Lenza
Keyword(s):  
Regional Scale ◽  
Basal Area ◽  
Floristic Composition ◽  
Sensu Stricto ◽  
Deep Soil ◽  
Important Species ◽  
Rocky Outcrop ◽  
Influence Of Substrate ◽  
Set Up ◽  
Habitat Specialist Species

We described and compared the floristic composition, richness, species diversity and structure of the tree-shrub component in pairs of Typical Cerrado (Cerrado Típico) and rocky outcrop Cerrado (Cerrado Rupestre) in two localities in Tocantins State. In each locality, we set up 10 plots of 20 × 50 m at a site, the Cerrado Típico and other Cerrado Rupestre, and sampled the individuals with Db30cm ≥ 5 cm. The rocky outcrop Cerrado did not present any trend towards lower richness and basal area compared to the Cerrado on deep soil. Few species occurred across the four sites and only two important species (Anacardium occidentale and Qualea parviflora) in the four vegetation structure were common to both environments assessed. Furthermore, the occurrence of habitat-specialist species of rocky outcrops and high altitudes (Mimosa claussenii, Tibouchina papyrus, Schwartzia adamantium and Wunderlichia cruelsiana) and the high dissimilarity among sites suggest that altitude is the main responsible for the floristic dissimilarity, followed by the influence of substrate type. Therefore, the information with respect to phytophysiognomy type as a parameter to select areas for conservation, by itself, does not effectively ensure biodiversity preservation, owing to the existing flora heterogeneity not only at local but also at regional scale, revealed by the floristic and structural particularity of each site.

A woody plant community and tree-cacti associations change with distance to a water source in a dry Chaco forest of Argentina

2017 ◽  
Vol 39 (1) ◽  
pp. 15 ◽  
Author(s):  
Carolina B. Trigo ◽  
Andrés Tálamo ◽  
Mauricio M. Núñez-Regueiro ◽  
Enrique J. Derlindati ◽  
Gustavo A. Marás ◽  
...  
Keyword(s):  
Species Composition ◽  
Plant Community ◽  
Woody Plant ◽  
Spatial Association ◽  
Basal Area ◽  
Water Source ◽  
Grazing Pressure ◽  
Water Sources ◽  
Woody Vegetation ◽  
Total Species Richness

In semiarid regions, livestock is concentrated around water sources generating a piosphere pattern (gradients of woody vegetation degradation with increasing proximity to water). Close to the water source, livestock may affect the composition, structure and regeneration strategies of woody vegetation. We used the proximity from a water source as a proxy of grazing pressure. Our objectives were (1) to compare woody vegetation attributes (richness, diversity, species composition, density and basal area) and ground cover between sites at two distances to a water source: near (higher grazing pressure) and far from the water source (lower grazing pressure), and (2) to quantify and compare cases of spatial association among the columnar cacti Stetsonia coryne (Salm-Dyck) Britton and Rose (Cactaceae), and the dominant tree Bulnesia sarmientoi Lorentz ex Griseb. (Zygophyllaceae). We used a paired design with eight pairs of rectangular plots distributed along a large and representative natural water source. We found lower total species richness, plant density and soil cover near than far from water source, and more cases of spatial associations between the two species studied. Our results show evidence of increased livestock impacts around water sources. However, we found no difference in terms of species composition or basal area at near versus far sites. We conclude that grazing pressure might be changing some attributes of the woody plant community, and that the association of young trees with thorny plants (grazing refuge) could be a regeneration mechanism in this semiarid forest with high grazing pressure.

scholarly journals Past, present, future: tracking and simulating genetic differentiation over time in a closed metapopulation system

2021 ◽  
Author(s):  
Florian Kunz ◽  
Annette Kohnen ◽  
Ursula Nopp-Mayr ◽  
Joy Coppes
Keyword(s):  
Genetic Differentiation ◽  
Extinction Risk ◽  
Recent Time ◽  
Conservation Strategies ◽  
Tetrao Urogallus ◽  
Migration Rates ◽  
Time Period ◽  
Conservation Concern ◽  
Set Up ◽  
Over Time

AbstractGenetic differentiation plays an essential role in the assessment of metapopulation systems of conservation concern. Migration rates affect the degree of genetic differentiation between subpopulations, with increasing genetic differentiation leading to increasing extinction risk. Analyses of genetic differentiation repeated over time together with projections into the future are therefore important to inform conservation. We investigated genetic differentiation in a closed metapopulation system of an obligate forest grouse, the Western capercaillieTetrao urogallus, by comparing microsatellite population structure between a historic and a recent time period. We found an increase in genetic differentiation over a period of approximately 15 years. Making use of forward simulations accounting for population dynamics and genetics from both time periods, we explored future genetic differentiation by implementing scenarios of differing migration rates. Using migration rates derived from the recent dataset, simulations predicted further increase of genetic differentiation by 2050. We then examined effects of two realistic yet hypothetical migration scenarios on genetic differentiation. While isolation of a subpopulation led to overall increased genetic differentiation, the re-establishment of connectivity between two subpopulations maintained genetic differentiation at recent levels. Our results emphasize the importance of maintaining connectivity between subpopulations in order to prevent further genetic differentiation and loss of genetic variation. The simulation set-up we developed is highly adaptable and will aid researchers and conservationists alike in anticipating consequences of conservation strategies for metapopulation systems.

Grafinscripties

Lampas ◽  
2021 ◽  
Vol 54 (1) ◽  
pp. 39-65
Author(s):  
Onno van Nijf
Keyword(s):  
Late Antiquity ◽  
Archaic Period ◽  
Social Strategies ◽  
Public And Private ◽  
Content Type ◽  
Frequent Type ◽  
The Social ◽  
Funerary Inscriptions ◽  
Set Up ◽  
Over Time

Abstract This article offers a brief introduction to the most frequent type of inscription: funerary inscriptions or epitaphs. The article offers a chronological overview from the Archaic period to late Antiquity, with an emphasis on Athens. It opens with a brief discussion of the archaeological and ritual contexts in which funerary inscriptions were set up, followed by a discussion of archaic epigrams and the social strategies that lay behind them. This is followed by a discussion of public and private graves that shows how epigraphic habits changed over time. The article continues with a discussion of funerary epigraphic habits outside Athens and closes with a few examples of Christian epitaphs.

Genetic gap analysis of wildHordeumtaxa

2012 ◽  
Vol 10 (3) ◽  
pp. 242-253 ◽  
Author(s):  
Holly Vincent ◽  
Roland von Bothmer ◽  
Helmut Knüpffer ◽  
Ahmed Amri ◽  
Jan Konopka ◽  
...  
Keyword(s):  
Gap Analysis ◽  
Plant Genetic Resources ◽  
Ex Situ ◽  
Conservation Strategies ◽  
Gene Pools ◽  
Barley Plant ◽  
Genetic Reserve ◽  
Set Up ◽  
Global Inventory

To facilitate the updating ofin situandex situconservation strategies for wild taxa of the genusHordeumL., a combined ecogeographic survey and gap analysis was undertaken. The analysis was based on the Global Inventory of Barley Plant Genetic Resources held by ICARDA plus additional datasets, resulting in a database containing 17,131 wildHordeumaccessions. The analysis concluded that a genetic reserve should be established in the Mendoza Province of Argentina, as this is the most species-rich area globally forHordeum. A network of reserves should also be set up across the Fertile Crescent in Israel, Palestine, Syria, Jordan, Lebanon and Turkey to provide effective conservation within the centres of diversity for gene pools 1B (Hordeum vulgaresubsp.spontaneum(C. Koch) Thell.) and 2 (Hordeum bulbosumL.). The majority of the species were deemed under-collected, so further collecting missions are required worldwide where possible. Althoughex situandin situconservation strategies have been developed, there needs to be further investigation into the ecological environments thatHordeumspecies occupy to ensure that any adaptive traits expressed are fully conserved. Additionally, studies are required to characterize existing collections and test the viability of rare species accessions held in genebanks to determine whether furtherex situcollections are required alongside the proposedin situconservation.

scholarly journals Climate and plant community diversity in space and time

2020 ◽  
Vol 117 (9) ◽  
pp. 4464-4470 ◽  
Author(s):  
Susan Harrison ◽  
Marko J. Spasojevic ◽  
Daijiang Li
Keyword(s):  
Plant Community ◽  
Plant Diversity ◽  
Phylogenetic Diversity ◽  
Spatial Scales ◽  
Community Diversity ◽  
Niche Conservatism ◽  
Space And Time ◽  
Drying Trend ◽  
Functional And Phylogenetic Diversity ◽  
Over Time

Climate strongly shapes plant diversity over large spatial scales, with relatively warm and wet (benign, productive) regions supporting greater numbers of species. Unresolved aspects of this relationship include what causes it, whether it permeates to community diversity at smaller spatial scales, whether it is accompanied by patterns in functional and phylogenetic diversity as some hypotheses predict, and whether it is paralleled by climate-driven changes in diversity over time. Here, studies of Californian plants are reviewed and new analyses are conducted to synthesize climate–diversity relationships in space and time. Across spatial scales and organizational levels, plant diversity is maximized in more productive (wetter) climates, and these consistent spatial relationships are mirrored in losses of taxonomic, functional, and phylogenetic diversity over time during a recent climatic drying trend. These results support the tolerance and climatic niche conservatism hypotheses for climate–diversity relationships, and suggest there is some predictability to future changes in diversity in water-limited climates.

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.

scholarly journals Altitudinally coordinated pattern of plant community structure in the Shivapuri National Park, Nepal

1970 ◽  
Vol 18 (1) ◽  
pp. 11-17 ◽  
Author(s):  
Shalik Ram Sigdel
Keyword(s):  
Community Structure ◽  
Species Diversity ◽  
Plant Species ◽  
Plant Community ◽  
National Park ◽  
Climatic Factors ◽  
Flower Colour ◽  
Basal Area ◽  
Plant Community Structure ◽  
Closed Canopy

Study on plant community structure was undertaken in different altitudinal ranges of Shivapuri National Park. The general objective of this study is to analyse different plant community structure in Shivapuri National Park with regards to altitudinal variation. The forest was divided into three distinct altitudinal ranges on the basis of dominancy. In each altitudinal range standard quadrats method was applied for vegetation analysis. The highest number of species was found in site II. All the ecological parameters of the plant species were higher in site II except Basal Area of tree that was highest in site III. The pattern of distribution of plant species was not uniform according to altitude. At higher elevation, the forest was mature with almost closed canopy and trees were large; so the tree density was low. Species richness was highest in site II. Species diversity among tree and shrub species was higher in site I. But for herb species diversity was higher in site II for both seasons. Such type of variations may be due to nature of soil i.e. acidity, nutrient availability and other micro-climatic factors. The most noteworthy thing was that variation in flower colour of Rhododendron arboreum i.e. deep scarlet at low altitude, but it gradually changed into pinkish white as altitude increased. Key words: Altitude, Density, Plant community, Species diversity doi: 10.3126/banko.v18i1.2161 Banko Janakari, Vol. 18, No. 1, 11-17

scholarly journals Antarctic Fish as a Global Pollution Sensor: Metals Biomonitoring in a Twelve-Year Period

2021 ◽  
Vol 8 ◽  
Author(s):  
Alessandro Marrone ◽  
Daniele La Russa ◽  
Elvira Brunelli ◽  
Gianfranco Santovito ◽  
Mauro Francesco La Russa ◽  
...  
Keyword(s):  
Ross Sea ◽  
Antarctic Fish ◽  
Conservation Strategies ◽  
Early Step ◽  
Low Latitudes ◽  
Contamination Levels ◽  
Global Threat ◽  
Land Water ◽  
Natural Laboratory ◽  
Over Time

Antarctica represents a unique natural laboratory for ecotoxicological studies as it is characterized by low internal pollutants emissions but high external contamination levels. Indeed, warm temperatures promote pollutant evaporation (low latitudes), while cool temperatures (high latitudes) promote its deposition from the atmosphere on land/water. Metals are the most important pollutants in ecosystems and represent a serious and global threat to aquatic and terrestrial organisms. Since 2000, the risks posed by metals have led many States to ratify protocols aimed at reducing their emissions. Endemic Antarctic organisms represent excellent bioindicators in order to evaluate the efficacy of global measures adopted to mitigate pollutants release into the environment. In this study (supported by PNRA18-00133), we estimated the metals contamination levels and the metallothionein-1 expression in liver samples of two Antarctic fish species, the icefish Chionodraco hamatus and the red-blooded Trematomus bernacchii, collected in the same area during 2002 and 2014. The chosen area is located in the Ross Sea, a unique area as it is also isolated from the rest of the Southern Ocean. The analysis of contamination trends throughout this period showed, in both species, a significant increase over time of metals bioaccumulation and metallothionein-1 expression. In addition, our result clearly indicated that the detoxifying ability of the two organisms analyzed greatly differs, probably due to haemoglobin presence/absence. Our work represents an important early step to obtain valuable information in conservation strategies for both Antarctic and non-Antarctic ecosystems.

scholarly journals A Pilot Study on Home Range and Habitat Use of Chinese Goral (Naemorhedus Griseus): Exploring GPS Tracking Data in Cliff Landscape by Three Estimation Methods

2021 ◽  
Author(s):  
yang teng ◽  
Shupei TANG ◽  
lai heda meng ◽  
Liji Wu ◽  
Zhiqing HAN ◽  
...  
Keyword(s):  
Home Range ◽  
Habitat Use ◽  
Estimation Methods ◽  
Conservation Strategies ◽  
Gps Tracking ◽  
Tracking Data ◽  
Size Estimation ◽  
Range Estimation ◽  
Lower Altitude ◽  
Effective Conservation

Abstract Home range size estimation is a crucial basis for developing effective conservation strategies and provides important insights into animal behavior and ecology. This study aimed at analyzing the home range variations, the influence of altitude in habitat selection, and comparing three methods in home range estimation of Chinese gorals (Naemorhedus griseus) living at a cliff landscape. The results indicated that there were significant differences between the annual home range sizes of individual animals but there was no difference in their seasonal home range sizes based on GPS tracking data of five female Chinese gorals from February 2015 to September 2018. The monthly home ranges decreased dramatically in May, June and July due to birth-giving. Notable seasonal variations were found in the micro-habitats of the Chinese gorals, as reflected by the altitude they inhabit, with higher altitude habitats used in spring and lower altitude habitats used in winter. Additionally, the altitude of monthly habitats was lowest in January, which may indicate an adaptation to low air temperature. We also found differences between estimation methods, namely minimum convex polygon (MCP), kernel density estimation (KDE) and α-local convex hull (α-LoCoH), with seasonal home range sizes derived from α-LoCoH being substantially smaller than those derived from MCP and KDE. In conclusion, our findings filled the gaps in home range study for this endangered species and contributed to effective conservation strategies. Considerations shall have to be given to the variations in home range estimation caused by different methods when dealing with rugged habitats, so as to make sure that any interpretation concerning the habitat use of the targeted species made on basis of such results would be meaningful and valid.

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