Studies on the origin, evolution and distribution of the Gramineae. I. The tribe Andropogoneae

1958 ◽  
Vol 6 (2) ◽  
pp. 116 ◽  
Author(s):  
W Hartley
Keyword(s):  
Climatic Factors ◽  
Western Hemisphere ◽  
Western India ◽  
High Concentration ◽  
Cytological Evidence ◽  
Origin And Evolution ◽  
Eastern Hemisphere ◽  
Winter Temperatures ◽  
The Tropics ◽  
World Distribution

From a study of the grass flora of some 300 regions, a world distribution map of the grass tribe, Andropogoneae, has been prepared. This map shows that the Indo-Malaysian region is relatively rich in species of the tribe, with zones of high concentration in western India and in southern Indonesia. The relative species density falls off rapidly in passing from the tropical to the temperate zones, and is lower in the western than in the eastern hemisphere. Climatic factors are of major importance in determining the distribution pattern. Winter temperatures are of special significance in temperate regions, while there is a striking relationship between high midsummer rainfall and relative abundance of species of Andropogoneae in the tropics and subtropics. In general, the geographical survey supports conclusions drawn from taxonomic and cytological evidence regarding the origin and evolution of the tribe, but with greater emphasis on climate as a significant factor. The Andropogoneae have had a long evolutionary history in the eastern hemisphere, but have spread more recently to the western hemisphere, where they have not yet attained their full development.

Studies on the origin, evolution, and distribution of the Gramineae. III. The tribes of the subfamily Eragrostoideae

1960 ◽  
Vol 8 (3) ◽  
pp. 256 ◽  
Author(s):  
W Hartley ◽  
C Slater
Keyword(s):  
Wide Distribution ◽  
Western India ◽  
Distribution Maps ◽  
Winter Temperatures ◽  
Close Relationship ◽  
Hot Arid Climate ◽  
South West Africa ◽  
The Tropics ◽  
World Distribution ◽  
North Western

In further studies of grass distribution, maps are presented showing the world distribution of the Eragrosteae (sensu str.) and of the subfamily Eragrostoideae within which it is included. Both taxa show centres of high relative specific differentiation in inland Australia and in South West Africa, but in addition, the subfamily has centres of differentiation in the Sahara rekion, northern Mexico, and north-western India. The centres of differentiation are all in regions of hot, arid climate near the tropics of Cancer and Capricorn. The close relationship between climate and distribution is most apparent in the case of the subfamily Eragrostoideae, species of which are relatively abundant in the grass flora of all arid regions with high winter temperatures and summer or non-seasonal rainfall incidence. The distributions of most of the other tribes and subtribes which have been included in the Eragrostoideae show a similar relationship to climate. Some apparent exceptions to this are discussed, and it is shown that the geographical evidence supports conclusions from recent cytotaxonomic and anatomical studies that the taxa concerned should be removed from the subfamily. The very wide distribution of the subfamily and of its constituent taxa, as well as the close relationship between the distribution pattern and climate, suggests that the subfamily is a very old one. Geographical and taxonomic evidence indicates that it may have originated in tropical or subtropical Africa at least as early as the Oligocene.

Studies on the origin, evolution, and distribution of the Gramineae. II. The tribe Paniceae

1958 ◽  
Vol 6 (4) ◽  
pp. 343 ◽  
Author(s):  
W Hartley
Keyword(s):  
Climatic Factors ◽  
The United States ◽  
Western Hemisphere ◽  
Annual Rainfall ◽  
Large Measure ◽  
Eastern Hemisphere ◽  
North Eastern ◽  
Close Relationship ◽  
Present Distribution ◽  
The Tropics

A world distribution map of the tribe Paniceae has been prepared, based on the percentage frequency of species of Paniceae in the total grass flora of each region. The map shows that relative specific differentiation is higher in the western hemisphere than in the eastern hemisphere, and that there is a zone of maximum concentration in north-eastern South America. The significance of this distribution pattern is discussed, and it is shown that the taxonomic evidence does not support a New World origin for the tribe. The distribution of the Paniceae in the United States shows a close relationship to winter temperature, and especially to annual rainfall. These climatic factors are also of major importance in other parts of the world, and in large measure explain the present distribution of the tribe. The Paniceae and Andropogoneae both appear to be "natural" tribes, which probably originated from a common panicoid stock in the warmer parts of the eastern hemisphere, possibly in the East Africa–Madagascar region. The Paniceae spread rapidly throughout the tropics and subtropics of both hemispheres, especially in the equatorial zone with high temperatures and well distributed rainfall. They show a pattern of climatic adaptation differing from that of the Andropogoneae. The latter, apparently formed more recently from the panicoid stock, reach their highest development in monsoonal climates with a much shorter season of heavy rainfall.

scholarly journals NUIST ESM v3 Data Submission to CMIP6

2021 ◽  
Author(s):  
Jian Cao ◽  
Libin Ma ◽  
Fei Liu ◽  
Jing Chai ◽  
Haikun Zhao ◽  
...  
Keyword(s):  
Information Science ◽  
Surface Air Temperature ◽  
Western Hemisphere ◽  
Earth System ◽  
Eastern Hemisphere ◽  
Scenario Model ◽  
Intercomparison Project ◽  
The Tropics ◽  
The Tropical Pacific

AbstractThis paper introduces the experimental designs and outputs of the Diagnostic, Evaluation and Characterization of Klima (DECK), historical, Scenario Model Intercomparison Project (MIP), and Paleoclimate MIP (PMIP) experiments from the Nanjing University of Information Science and Technology Earth System Model version 3 (NESM3). Results show that NESM3 reasonably simulates the modern climate and the major internal modes of climate variability. In the Scenario MIP experiment, changes in the projected surface air temperature (SAT) show robust “Northern Hemisphere (NH) warmer than Southern Hemisphere (SH)” and “land warmer than ocean” patterns, as well as an El Niño-like warming over the tropical Pacific. Changes in the projected precipitation exhibit “NH wetter than SH” and “eastern hemisphere gets wetter and western hemisphere gets drier” patterns over the tropics. These precipitation patterns are driven by circulation changes owing to the inhomogeneous warming patterns. Two PMIP experiments show enlarged seasonal cycles of SAT and precipitation over the NH due to the seasonal redistribution of solar radiation. Changes in the climatological mean SAT, precipitation, and ENSO amplitudes are consistent with the results from PMIP4 models. The NESM3 outputs are available on the Earth System Grid Federation nodes for data users.

Morphological types of spermatheca in Coreidae: bearing on intra-familial classification and tribal-groupings (Hemiptera: Heteroptera)

Zootaxa ◽  
2020 ◽  
Vol 4834 (4) ◽  
pp. 451-501
Author(s):  
DOMINIQUE PLUOT-SIGWALT ◽  
PIERRE MOULET
Keyword(s):  
Western Hemisphere ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Spermathecal Duct ◽  
Eastern Hemisphere ◽  
Intermediate Part ◽  
Muscular Pump ◽  
Familial Classification

The morphology of the spermatheca is described in 109 species of 86 genera representing all four currently recognised subfamilies of Coreidae, covering the undivided Hydarinae, both tribes of Pseudophloeinae, all three tribes of Meropachyinae and 27 of the 32 tribes of Coreinae. Three types of spermatheca are recognised. Type I is bipartite, consisting only of a simple tube differentiated into distal seminal receptacle and proximal spermathecal duct and lacks the intermediate part present in most Pentatomomorpha, in which it serves as muscular pump. Type II is also bipartite but more elaborate in form with the receptacle generally distinctly wider than the duct. Type III is tripartite, with receptacle, duct and an often complex intermediate part. Four subtypes are recognised within type III. Type I is found only in Hydarinae and type II only in Pseudophloeinae. Type III is found in both Coreinae and Meropachyinae. Subtype IIIA (“Coreus-group”) unites many tribes from the Eastern Hemisphere and only one (Spartocerini) from the Western Hemisphere. Subtypes IIIB (“Nematopus-group”) and IIID (“Anisoscelis-group”) are confined to taxa from the Western Hemisphere and subtype IIIC (“Chariesterus-group”) is found in tribes from both hemispheres. The polarity of several characters of the intermediate part and some of the spermathecal duct is evaluated, suggesting autapomorphies or apomorphies potentially relevant to the classification of Coreidae at the sufamilial and tribal levels. Characters of the intermediate part strongly indicate that the separation of Meropachyinae and Coreinae as currently constituted cannot be substantiated. The tribes Anisoscelini, Colpurini, Daladerini and Hyselonotini are heterogeneous, each exhibiting two subtypes of spermatheca, and probably polyphyletic. Two tribes, Cloresmini and Colpurini, requiring further investigation remain unplaced. This study demonstrates the great importance of characters of the spermatheca, in particular its intermediate part, for research into the phylogeny and taxonomy of Pentatomomorpha. 

scholarly journals Convectively Coupled Equatorial Waves. Part I: Horizontal and Vertical Structures

2007 ◽  
Vol 64 (10) ◽  
pp. 3406-3423 ◽  
Author(s):  
Gui-Ying Yang ◽  
Brian Hoskins ◽  
Julia Slingo
Keyword(s):  
Composite Structures ◽  
Wave Structure ◽  
Wave Theory ◽  
Western Hemisphere ◽  
Equatorial Waves ◽  
Kelvin Wave ◽  
Ambient Flow ◽  
Convectively Coupled Equatorial Waves ◽  
Eastern Hemisphere ◽  
Equatorial Wave

Abstract Multilevel 15-yr ECMWF Re-Analysis (ERA-15) and satellite-observed brightness temperature (Tb) data for the period May–October 1992 are used to examine the horizontal and vertical structures of convectively coupled equatorial waves. Dynamical waves are isolated using a methodology developed previously. Composite structures of convectively coupled equatorial waves are obtained using linear regression/correlation between convection (Tb) and dynamical structures. It is found that the relationship depends on the ambient flow and the nature of the convective coupling, and varies between off-equatorial- and equatorial-centered convection, different hemispheres, and seasons. The Kelvin wave structure in the Western Hemisphere is generally consistent with classic equatorial wave theory and has its convection located in the region of low-level convergence. In the Eastern Hemisphere the Kelvin wave tends to have convection in the region of enhanced lower-tropospheric westerlies and a tilted vertical structure. The Kelvin wave also tends to have a third peak in zonal wind amplitude at 500 hPa and exhibits upward propagation into the lower stratosphere. Lower-tropospheric westward-moving mixed Rossby–gravity (WMRG) and n = 1 Rossby (R1) wave structures and their relationship with convection are consistent with classic equatorial wave theory and the implied lower-tropospheric convergences. In the Eastern Hemisphere the WMRG and R1 waves have first baroclinic mode structures in the vertical. However, in the Western Hemisphere, the R1 wave has a barotropic structure. In the Eastern Hemisphere the R1 wave, like the Kelvin wave, tends to have equatorial convection in the region of enhanced lower-level westerlies, suggesting that enhanced surface energy fluxes associated with these waves may play an important organizing role for equatorial convection in this warm-water hemisphere. In the upper troposphere, eastward-moving Rossby–gravity (EMRG) and n = 1 gravity waves are found in the Eastern Hemisphere, and eastward-moving WMRG and R1 waves are found in the Western Hemisphere, suggestive of Doppler shifting of waves by the ambient flow.

Aschersonia aleyrodis. [Descriptions of Fungi and Bacteria].

1984 ◽  
Author(s):  
B. L. Brady
Keyword(s):  
Costa Rica ◽  
Geographical Distribution ◽  
Solomon Islands ◽  
Western Hemisphere ◽  
Scale Insects ◽  
Infected Host ◽  
Santo Domingo ◽  
Eastern Hemisphere ◽  
Aschersonia Aleyrodis ◽  
The Relationship

Abstract A description is provided for Aschersonia aleyrodis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Scale insects (Coccidae) and whitefly (Aleyrodidae). GEOGRAPHICAL DISTRIBUTION: Costa Rica, Cuba, India, Jamaica, Santo Domingo, Solomon Islands, USA. According to Mains (1959) A. aleyrodis is very common in the Western hemisphere whereas A. placenta is common in the Eastern hemisphere. DISEASE: When the genus Aschersonia Montagne was described in 1848 the species were regarded as parasites of the leaves of the plants on which the insect hosts were located and it was only in 1894 that Webber recognized A. aleyrodis as entomogenous. Early work and the relationship with the ascomycete genus Hypocrella is extensively treated and illustrated in colour by Petch (1921). Sutton (1980) states that approximately 50 taxa have been described in the genus which is wholly entomogenous. Infection is mainly of young larvae, but mature larvae and pupae are also attacked. Larvae in the early stages of infection become swollen and by the time that hyphae emerge around the edge of the infected host the latter is already dead.

scholarly journals Effects of Life-form and Plants Functional Traits on Carbon, Nitrogen and Sulfur Distributed in Different Parts in Dry Region of Western India

2021 ◽  
Author(s):  
Genda Singh ◽  
Bilas Singh
Keyword(s):  
Functional Traits ◽  
Life Form ◽  
Life Forms ◽  
Climatic Conditions ◽  
Western India ◽  
High Concentration ◽  
N Content ◽  
Medicinal Uses ◽  
Leguminous Species ◽  
C And N

Abstract Background: Plants adapt to adverse environmental conditions accumulate varying concentrations of carbon (C), nitrogen (N) and sulfur (S) compounds to cope up with adverse climatic conditions. Carbon, N and S concentrations were determined in roots, stem and leaves of 33 species of trees/shrubs with objectives to observe the effects of life-form and plants functional traits, and select species with high concentration of these elements for their utilization in afforestation and medicinal uses. Results: Concentrations of C, N, and S and C: N and N: S ratio varied (P<0.05) between species, organs, life-forms and functional traits (legume vs non-legume). These variables were higher (except C in roots and stem) in trees than shrubs, and in leguminous than non-leguminous species. Non-leguminous species showed high S content and low N: S ratio. Antagonistic and synergistic relations were observed between C and N, and N and S concentration respectively. Species showed varying potential in assimilating carbon by regulating uptake and accumulation of these elements in different organs making them adapt to the habitats affected by drought and salinity. We observed strong plant size/life-form effects on C and N content and C: N and N: S ratios and of function on S content. Conclusions: Life-form/size and varying functions of the species determined C: nutrient ratio and elemental composition and helped adapting varying environmental stresses. This study assist in selecting species of high carbon, nitrogen and S content to utilize them in afforesting the areas affected by water and salt stresses, increased carbon storage and species with high S/N content in medicinal uses.

Khuskia oryzae. [Descriptions of Fungi and Bacteria].

1971 ◽  
Author(s):  
A. Sivanesan
Keyword(s):  
Zea Mays ◽  
Oryza Sativa ◽  
Geographical Distribution ◽  
Saccharum Officinarum ◽  
Diurnal Periodicity ◽  
Western Hemisphere ◽  
Plant Debris ◽  
Stalk Rot ◽  
Rare Phenomenon ◽  
The Tropics

Abstract A description is provided for Khuskia oryzae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Plurivorous, especially on monocotyledons and particularly on Oryza sativa, Saccharum officinarum, Zea mays and Musa spp. DISEASE: Causes cob and stalk rot of maize (11: 711; 12: 20; 13: 299, 571; 43, 3205; 44, 2123) and on sorghum as stem and grain infection (43, 727); it is common on banana debris in the western hemisphere and can cause discolouration in rice irain. On maize, symptoms develop towards maturity mostly on the shanks, husks and ears but also on the stems and stalks, where blackish, shallow lesions can occur. Ears may snap off at harvest; the cob becomes shredded and rotten through disintegration of the parenchyma, sparse mycelium and sporulation develop in the furrows between kernels and on the seed itself. GEOGRAPHICAL DISTRIBUTION: Widespread, principally as a member of the saprophytic flora on plant debris in warmer areas. TRANSMISSION: Infection of seed reduces its quality rather than causing the fungus to be really seed-borne. A diurnal periodicity has been reported for Nigrospora sphaerica and K. oryzae, with a peak at 0800-1000 hr, in the tropics (35: 383; 41: 242). Violent spore discharge, a rare phenomenon in the hyphomycetes, has been described for N. sphaerica (31: 56).

The Doors of America Are Worse Than Shut When They Are Half-Way Open

Unwanted ◽  
2020 ◽  
pp. 43-70
Author(s):  
Maddalena Marinari
Keyword(s):  
Common Ground ◽  
Family Reunification ◽  
Western Hemisphere ◽  
Southern Europe ◽  
Immigration Reform ◽  
Quota System ◽  
Immigration Restriction ◽  
Jewish Immigration ◽  
Eastern Hemisphere ◽  
European Immigration

Chapter 2 offers an account of how Italian and Jewish immigration reform advocates, sensing the inevitability of further restriction, pragmatically decided to work with legislators in the early 1920s to mitigate some of the more punitive features of the national origins quota system. When the literacy test passed in 1917 failed to halt immigration from eastern and southern Europe significantly, restrictionists in and outside of Congress began pushing for quantitative immigration restriction. In 1924, Congress passed the Johnson-Reed Act, which imposed the national origins quota system for immigration from the Eastern Hemisphere and a near ban on immigration from Asia. The only issue on which restrictionist legislators and Italian and Jewish anti-restrictionists could find common ground when it came to immigration reform was family reunification, but legislators refused to budge on the discriminatory national quotas imposed on European immigration. Although scholars usually present the 1920s and 1930s as the height of immigration restriction, these negotiations over family reunification, along with the exemption of the Western Hemisphere from the quota system, allowed for exclusion and inclusion to continue to coexist in U.S. immigration policy.

Climatic Factors Under the Tropics

2018 ◽  
pp. 25-39
Author(s):  
Jacques Reis ◽  
Pascal Handschumacher ◽  
Valerie S. Palmer ◽  
Peter S. Spencer
Keyword(s):  
Climatic Factors ◽  
The Tropics
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