Male-skewed sex ratio in Myrica esculenta: a dioecious tree species

Trees ◽  
2019 ◽  
Vol 33 (4) ◽  
pp. 1157-1165 ◽  
Author(s):  
Vinod Prasad Khanduri ◽  
Arun Sukumaran ◽  
Chandra Mohan Sharma
Keyword(s):  
Sex Ratio ◽  
Tree Species ◽  
Myrica Esculenta

scholarly journals ELEVATIONAL DISTRIBUTION OF TREE DIVERSITY IN LOWER HIMALAYA: A CASE STUDY OF PHULCHOKI HILL, NEPAL

2015 ◽  
Vol 4 (3) ◽  
pp. 130-139 ◽  
Author(s):  
Ruska Kattel ◽  
Bimala Devkota ◽  
Laxman K.C.
Keyword(s):  
Species Diversity ◽  
Tree Species ◽  
Linear Trend ◽  
Average Density ◽  
Shannon Index ◽  
Managed Forest ◽  
Tree Species Composition ◽  
Lower Elevation ◽  
Evenness Index ◽  
Myrica Esculenta

 Changes in tree species composition with elevation have been studied at three distinct altitudinal ranges on the basis of dominance, in sub-tropical and temperate forests on south slopes of Phulchoki hill, central part of lower Himalaya, Nepal. The greatest number of tree species was found in the low altitude (1600 m), followed by intermediate altitude (1950 m). The highest altitude (2650 m) contained only one distinct tree species (Oak). Site I has higher species diversity (Shannon Index: 2.1863, Evenness Index: 0.852) and density (5575 individual per hectare) dominated by Castonopsis indica, Quercus glauca, Myrica esculenta and myrsine capitellate. Site II has average species diversity (Shannon Index: 1.759, Evenness Index: 0.9) and an average density (2150 individual per hectare) dominated by Rhododendron arboretum, Castanopsis tribuloides and Quercus incana. At site III the forest is entirely dominated by Quercus semicarpifolia, a high altitude Oak. A linear trend of decreasing tree species diversity and density along with elevations was seen which might be because of intense afforestation by communities at lower elevation as site I and II under community managed forest and lower altitudinal ecozone with clear zonation of elevational vegetation types.International Journal of Environment Volume-4, Issue-3, June-August 2015Page: 130-139

Population Biology of Euperipatoides-Leuckartii (Onychophora, Peripatopsidae)

1991 ◽  
Vol 39 (5) ◽  
pp. 499 ◽  
Author(s):  
IAW Scott ◽  
DM Rowell
Keyword(s):  
Sex Ratio ◽  
Water Content ◽  
Population Study ◽  
Tree Species ◽  
Relative Water Content ◽  
Population Biology ◽  
Age At Maturity ◽  
Correlated Variables ◽  
Age Cohorts ◽  
Relative Water

This paper reports on a population study of the onychophoran Euperipatoides leuckartii. The species was found to be extremely abundant in decomposing logs from the Tallaganda State Forest area. Analysis of its distribution indicated that E. leuckartii occurred only in logs with a relative water content greater than 211 %. Furthermore, the occurrence of E. leuckartii was found to be congruent with that of termites. Abundance was also correlated with altitude, which suggests an effect of tree species, although other correlated variables may be implicated. Overall, sex ratio was found to be heavily skewed in favour of females. However, the sex ratio was not homogeneous among age cohorts or logs. The skewed overall sex ratio is considered to be a result of differential lifespans and age at maturity of the sexes, and a model for log-colonisation patterns is presented that may explain the differences in peripatus sex ratios observed among logs.

scholarly journals Abundance, frequency and distribution pattern of tree species in recorded forest area of Western Himalaya

2020 ◽  
Vol 12 (2) ◽  
pp. 341-355
Author(s):  
Arun K. THAKUR ◽  
Rajesh KUMAR ◽  
Raj K. VERMA
Keyword(s):  
Forest Management ◽  
Distribution Pattern ◽  
Tree Species ◽  
Western Himalaya ◽  
National Forest Inventory ◽  
Forest Area ◽  
Wild Fruit ◽  
Intensive Forest Management ◽  
Morisita Index ◽  
Myrica Esculenta

The forest in India have a long history of human induced modifications through intensive forest management that began in the colonial period but continued afterwards to meet the wood-based demand until the forestry goals shifted towards conservation efforts. All this greatly influenced the plant community structure. We attempt to describe the abundance and distribution pattern of trees in recorded forestland of Western Himalaya using the National Forest Inventory database. A total of 3549 sample plots laid across different forest types were analyzed to reveal the abundance, frequency and distribution pattern of 226 tree species/genus using various indices i.e. abundance by frequency ratio, Morisita index and variance mean ratio. Twelve tree species and Eucalyptus genus were found to be most abundantly found tree species in recorded forest area of Western Himalaya. Ten tree species were found to have regular distribution pattern, one hundred ninety-two were contagiously distributed while twenty-five were randomly distributed. Results derived from huge datasets helps in establishing firm statements with quoted significance value. Myrica esculenta and Aegle marmelos were found among the most abundantly occurring tree species whereas Myrica esculenta, Syzygium cumini and Pyrus pashia, were among the most relatively frequently occurring wild fruit yielding tree species. These species (apart from fodder tree species) can be considered in social forest and joint forest management programs in forest fringe villages/areas to enhance and sustain the provisional ecosystem services in Western Himalaya.

Purification of plasma membranes from leaves of conifer and deciduous tree species by phase partitioning and free-flow electrophoresis

1995 ◽  
Vol 95 (3) ◽  
pp. 399-408 ◽  
Author(s):  
Elena Toll ◽  
Federico J. Castillo ◽  
Pierre Crespi ◽  
Michele Crevecoeur ◽  
Hubert Greppin
Keyword(s):  
Tree Species ◽  
Plasma Membranes ◽  
Free Flow ◽  
Deciduous Tree ◽  
Phase Partitioning

Die unbehandelten Kranken: Ältere Männer mit Depression

2008 ◽  
Vol 27 (07) ◽  
pp. 617-619 ◽  
Author(s):  
M. Wittmann ◽  
E. Haen ◽  
H. Spießl ◽  
H. Hausner
Keyword(s):  
Sex Ratio ◽  
Epidemiologische Studien

ZusammenfassungZahlreiche epidemiologische Studien zeigen, dass sich das Geschlechterverhältnis der Prävalenz depressiver Erkrankungen ab der 6. Lebensdekade – also nach der weiblichen Menopause – wieder annähert. Wir haben untersucht, ob sich dieser epidemiologische Effekt auch in der stationären Versorgung abbildet. Unter Verwendung der AGATE-Stichtagsdaten der Jahre 2000 bis 2004, wurde der Zusammenhang zwischen Geschlecht und Alter bei stationär behandelten depressiven Patienten analysiert. Der Zusammenhang zwischen Geschlechterverhältnis und dem Alter wurde mithilfe des Korrelationskoeffizienten nach Spearman sowie mit χ2-Test untersucht. In der 5. und 6. Lebensdekade lag die Sex-Ratio F/M bei 1,7:1, sie stieg in der 7. Dekade auf 2,2:1 und in der 8. Dekade auf 2,6:1 an. Anders als aufgrund epidemiologischer Studien zu erwarten wäre, nähert sich in der stationär psychiatrischen Versorgung das Verhältnis depressiver Patienten im Alter nicht an. Depressive ältere Männer sind also im stationären Versorgungssystem unterrepräsentiert.

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