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Link Between the Double-Intertropical Convergence Zone Problem and Cloud Biases Over the Southern Ocean
Link between the double-Intertropical Convergence Zone problem and cloud biases over the Southern Ocean Yen-Ting Hwang1 and Dargan M. W. Frierson Department of Atmospheric Sciences, University of Washington, Seattle, WA 98195-1640 Edited by Mark H. Thiemens, University of California at San Diego, La Jolla, CA, and approved February 15, 2013 (received for review August 2, 2012) The double-Intertropical Convergence Zone (ITCZ) problem, in which climate models show that the bias can be reduced by changing excessive precipitation is produced in the Southern Hemisphere aspects of the convection scheme (e.g., refs. 7–9) or changing the tropics, which resembles a Southern Hemisphere counterpart to the surface wind stress formulation (e.g., ref. 10). Given the complex strong Northern Hemisphere ITCZ, is perhaps the most significant feedback processes in the tropics, it is challenging to understand and most persistent bias of global climate models. In this study, we the mechanisms by which the sensitivity experiments listed above look to the extratropics for possible causes of the double-ITCZ improve tropical precipitation. problem by performing a global energetic analysis with historical Recent work in general circulation theory has suggested that simulations from a suite of global climate models and comparing one should not only look within the tropics for features that affect with satellite observations of the Earth’s energy budget. Our results tropical precipitation. A set of idealized experiments showed that show that models with more energy flux into the Southern heating a global climate model exclusively in the extratropics can Hemisphere atmosphere (at the top of the atmosphere and at the lead to tropical rainfall shifts from one side of the tropics to the surface) tend to have a stronger double-ITCZ bias, consistent with other (11). -
15. HIBISCUS Linnaeus, Sp. Pl. 2: 693. 1753, Nom. Cons
Flora of China 12: 286–294. 2007. 15. HIBISCUS Linnaeus, Sp. Pl. 2: 693. 1753, nom. cons. 木槿属 mu jin shu Bombycidendron Zollinger & Moritzi; Fioria Mattei; Furcaria (Candolle) Kosteletzky (1836), not Desvaux (1827); Hibiscus sect. Furcaria Candolle; H. sect. Sabdariffa Candolle; Ketmia Miller; Sabdariffa (Candolle) Kosteletzky; Solandra Murray (1785), not Linnaeus (1759), nor Swartz (1787), nom. cons.; Talipariti Fryxell. Shrubs, subshrubs, trees, or herbs. Leaf blade palmately lobed or entire, basal veins 3 or more. Flowers axillary, usually solitary, sometimes subterminal and ± congested into a terminal raceme, 5-merous, bisexual. Epicalyx lobes 5 to many, free or connate at base, rarely very short (H. schizopetalus) or absent (H. lobatus). Calyx campanulate, rarely shallowly cup-shaped or tubular, 5-lobed or 5-dentate, persistent. Corolla usually large and showy, variously colored, often with dark center; petals adnate at base to staminal tube. Filament tube well developed, apex truncate or 5-dentate; anthers throughout or only on upper half of tube. Ovary 5-loculed or, as a result of false partitions, 10-loculed; ovules 3 to many per locule; style branches 5; stigmas capitate. Fruit a capsule, cylindrical to globose, valves 5, dehiscence loculicidal and sometimes partially septicidal or indehiscent (H. vitifolius Linnaeus). Seeds reniform, hairy or glandular verrucose. About 200 species: tropical and subtropical regions; 25 species (12 endemic, four introduced) in China. According to recent molecular studies (Pfeil et al., Syst. Bot. 27: 333–350. 2002), Hibiscus is paraphyletic, and as more taxa are sampled and a more robust phylogeny is constructed, the genus undoubtedly will be recast. Species of other genera of Hibisceae found in China, such as Abelmoschus, Malvaviscus, and Urena, fall within a monophyletic Hibiscus clade. -
Palynological Study of Some Cultivated Species of Genus Hibiscus from North West Frontier Province (N.W.F.P.) Pakistan
Pak. J. Bot., 40(4): 1561-1569, 2008. PALYNOLOGICAL STUDY OF SOME CULTIVATED SPECIES OF GENUS HIBISCUS FROM NORTH WEST FRONTIER PROVINCE (N.W.F.P.) PAKISTAN NOREEN BIBI*1, MANZOOR HUSSAIN2 AND NAVEED AKHTAR3 1 Nuclear Institute of Agriculture and Biology Faisalabad, 2 Department of Botany Govt. Postgraduate College Abbottabad, 3 Department of Botany, University of Peshawar Abstract Pollen morphology of four species and three cultivars belonging to genus Hibiscus of family Malvaceae from North West Frontier Province (N.W.F.P.) of Pakistan were examined by light and scanning electron microscope. Pollen morphology of the family is fairly uniform. Pollen grains are generally radially symmetrical apolar, mostly spheroidal to oblate-spheroidal, pantoporate or polyporate. Tectum uniformly echinate, medium to finely perforated, or punctate with granules or scabrae in between spines. Introduction The family Malvaceae comprising of c. 88 genera and c. 2, 3000 species are distributed in tropical, subtropical and temperate regions (Willis, 1973; Mabberley, 1987). In Pakistan it is represented by 19 genera with 94 specific and intraspecific taxa (Abedin, 1979). Palynologically, Malvaceae is stenopalynous family and pollen characters in this family are more or less uniform. Culhane & Blackmore (1988) divided the family into six pollen type, based on number of apertures, grains diameter and spinular morphology. This is also supported by Christensen (1986) that the generic delimitation based on pollen morphology is difficult in this family. However, Saad (1960) considered that that the pollen morphology in the family Malvaceae is quite distinctive which could apparently distinguish between the genera. Whereas pollen morphology of the family Malvaceae has been studied by Master (1874), Lang (1937), Sayeeduddin et al (1942), Erdtman (1952), Nair (1958, 1960, 1962), Saad (1960), Chadhuri (1965), Fryxell & Hashmi (1971) and El Naggar (2004), but the most comprehensive study of the Malvaceae pollen is that of Christensen (1986). -
General Atmospheric Circulation of the Tropics
General Atmospheric Circulation of the Tropics By Herbert Riehl Department of Atmospheric Science Colorado State University Fort Collins, Colorado CURRENT PROBLEMS IN RESEi\RCII The General Atmospheric Circulation of the Tropics by Herbert Riehl Colorado State University In science. ,ve are always interested in a well-ordered simple package whenever such a package appears to be in the offing. There has been widespread belief that the general circulation of the tropics meets these requirements. The weather observations which have been gathered in increasing volume in the upper air over the tropics during the last 15 years" ho\vever, have thrown doubt on the validity of such a simple view. They appear to call for a more complex ap proach to an ultimate understanding of the tropical atmospheric ma chineryand of the interaction between tropical and temperate latitudes. The question no\v is: must we really accept an increased order of difficulty, or can the evidence of the new observations be reconciled with the older approach? If so, chances at arriving at a definite solu tion of the tropical general circulation problem within the next decade would be greatly enhanced.. In one respect the story has not changed; the tropics are a heat source for the atmosphere of higher latitudes. This fact, in broad terms. has been appreciated for centuries. Further, circumnaviga tion of the oceans by sailing vessels led to recognition of a second fact; the tropics also are the source of momentum for the westerly winds prevalent especially in temperate latitudes. Essentially half. of the globe has winds from east at the surface (fig. -
Coevolution of Cycads and Dinosaurs George E
Coevolution of cycads and dinosaurs George E. Mustoe* INTRODUCTION TOXICOLOGY OF EXTANT CYCADS cycads suggests that the biosynthesis of ycads were a major component of Illustrations in textbooks commonly these compounds was a trait that C forests during the Mesozoic Era, the depict herbivorous dinosaurs browsing evolved early in the history of the shade of their fronds falling upon the on cycad fronds, but biochemical evi- Cycadales. Brenner et al. (2002) sug- scaly backs of multitudes of dinosaurs dence from extant cycads suggests that gested that macrozamin possibly serves a that roamed the land. Paleontologists these reconstructions are incorrect. regulatory function during cycad have long postulated that cycad foliage Foliage of modern cycads is highly toxic growth, but a strong case can be made provided an important food source for to vertebrates because of the presence that the most important reason for the reptilian herbivores, but the extinction of two powerful neurotoxins and carcin- evolution of cycad toxins was their of dinosaurs and the contemporaneous ogens, cycasin (methylazoxymethanol- usefulness as a defense against foliage precipitous decline in cycad popula- beta-D-glucoside) and macrozamin (beta- predation at a time when dinosaurs were tions at the close of the Cretaceous N-methylamine-L-alanine). Acute symp- the dominant herbivores. The protective have generally been assumed to have toms triggered by cycad foliage inges- role of these toxins is evidenced by the resulted from different causes. Ecologic tion include vomiting, diarrhea, and seed dispersal characteristics of effects triggered by a cosmic impact are abdominal cramps, followed later by loss modern cycads. a widely-accepted explanation for dino- of coordination and paralysis of the saur extinction; cycads are presumed to limbs. -
Antimicrobial Efficacy of Hibiscus Schizopetalus (Mast) Hook
Hamdard Medicus Vol. 59, No. 4, 2016 Antimicrobial Efficacy of Hibiscus schizopetalus (Mast) Hook Hina Zahid*1, 2 and Ghazala H. Rizwani1, 3 Department of Pharmacognosy Faculty of Pharmaceutical Sciences: 1University of Karachi, 2Dow University of Health Sciences, 3Hamdard University, Karachi, Pakistan. *Email: [email protected] Abstract Keywords Plants are an important source of Antimicrobial, Hibiscus schizopetalus antimicrobial products, most of them are (Mast) Hook, methanolic extract, agar well efficacious against diverse organisms including diffusion and dilution methods. fungi, yeasts and bacteria, insects and nematodes. The present study was aimed at 1. INTRODUCTION measuring the antimicrobial effects of Resistance to antibiotics is one of the methanolic extract of flower and leaves of major problem facing public health world- Hibiscus schizopetalus (Mast) Hook. wide (Byarugaba, 2004; Okeke et al., 2005). It Antibacterial and antifungal activities of is a natural consequence of the adaption of H. schizopetalus extracts (HFE and HLE) infectious pathogens to antimicrobials used in were evaluated by the agar well diffusion and several areas, including medicine, food animals, agar dilution methods, respectively . The flower crop production and disinfectants in farms, extract of H. schizopetalus (HFE) revealed hospital and households (Bloomfield, 2002; antibacterial activity against Streptococcus McEwen and Fedorka-Cray; 2002; Vidaver, pyogenes, S. faecalis, Enterobacter 2002; Wise and Soulsby 2002). Bacteria have aerogenes and Proteus vulgaris with zone of developed resistance to all known antibiotics inhibition of 5 mm, 9 mm, 3 mm, 6 mm, and, as so, the economic burden associated with respectively. The extracts (HFE and HLE) these multidrug-resistant bacteria is high. In showed prominent activity against human order to find novel antimicrobial agents with pathogens Aspergillus flavus, A. -
Atoll Research Bulletin No. 503 the Vascular Plants Of
ATOLL RESEARCH BULLETIN NO. 503 THE VASCULAR PLANTS OF MAJURO ATOLL, REPUBLIC OF THE MARSHALL ISLANDS BY NANCY VANDER VELDE ISSUED BY NATIONAL MUSEUM OF NATURAL HISTORY SMITHSONIAN INSTITUTION WASHINGTON, D.C., U.S.A. AUGUST 2003 Uliga Figure 1. Majuro Atoll THE VASCULAR PLANTS OF MAJURO ATOLL, REPUBLIC OF THE MARSHALL ISLANDS ABSTRACT Majuro Atoll has been a center of activity for the Marshall Islands since 1944 and is now the major population center and port of entry for the country. Previous to the accompanying study, no thorough documentation has been made of the vascular plants of Majuro Atoll. There were only reports that were either part of much larger discussions on the entire Micronesian region or the Marshall Islands as a whole, and were of a very limited scope. Previous reports by Fosberg, Sachet & Oliver (1979, 1982, 1987) presented only 115 vascular plants on Majuro Atoll. In this study, 563 vascular plants have been recorded on Majuro. INTRODUCTION The accompanying report presents a complete flora of Majuro Atoll, which has never been done before. It includes a listing of all species, notation as to origin (i.e. indigenous, aboriginal introduction, recent introduction), as well as the original range of each. The major synonyms are also listed. For almost all, English common names are presented. Marshallese names are given, where these were found, and spelled according to the current spelling system, aside from limitations in diacritic markings. A brief notation of location is given for many of the species. The entire list of 563 plants is provided to give the people a means of gaining a better understanding of the nature of the plants of Majuro Atoll. -
Rhyzobius Lophanthae Introduced Against Asian
ABSTRACT Too Little and Too Late???? Asian Cycad Scale (ACS) Chronology Asian cycad scale (ACS), Aulacaspis yasumatsui, was 1972 – Aulacaspis yasumatsui described in Thailand first detected in Tumon, Guam in December 2003 in front Rhyzobius lophanthae introduced against Asian 1996 – ACS detected in Florida of a hotel where Cycas revoluta, an introduced ornamental 1998 – ACS detected in Hawaii cycad and Cycas micronesica, an indigenous cycad were cycad scale, Aulacaspis yasumatsui, on Guam 2003 – ACS detected on cycads used for landscaping in Guam’s planted. The scale is believed to have been imported from Tumon Bay hotel district Hawaii in 1998 on ornamental cycads. The scale currently R.H. Miller1, A. Moore1, R.N. Muniappan1, A.P. Brooke2 and T.E. Marler1. 2004 – ACS spreads to Cycas revoluta and C. micronesica infests introduced and indigenous cycads on about two 1CNAS-AES, University of Guam, Mangilao, Guam (fadang) throughout Guam thirds of Guam’s 354 square kilometers. Severe 2Guam National Wildlife Refuge, Dededo, Guam 2005 – Ryzobius lophanthae and Coccobius fulvus released on infestations have been observed to kill both species within Guam; Plans made to preserve C. micronesica germplasm from a few months. We fear that C. micronesica may be Guam on the nearby island of Tinian threatened with extinction should the scale spread to the few other Micronesian islands that harbor it. Rhyzobius lophanthae, a coccinellid introduced to Asian Cycad Scale Management Hawaii in 1894 for other scale insects, was imported from Biological Control Agents on Guam Maui to Guam in November 2004 and released on C. Rhyzobius lophanthae micronesica at the Guam National Wildlife Refuge at • Introduced in Hawaii in 1894; Guam ??? 1930s Ritidian point in February 2005. -
A Quarter Century of Pharmacognostic Research on Panamanian Flora: a Review*
Reviews 1189 A Quarter Century of Pharmacognostic Research on Panamanian Flora: A Review* Authors Catherina Caballero-George 1, Mahabir P. Gupta2 Affiliations 1 Institute of Scientific Research and High Technology Services (INDICASAT‑AIP), Panama, Republic of Panama 2 Center for Pharmacognostic Research on Panamanian Flora (CIFLORPAN), College of Pharmacy, University of Panama, Panama, Republic of Panama Key words Abstract with novel structures and/or interesting bioactive l" bioassays ! compounds. During the last quarter century, a to- l" Panamanian plants Panama is a unique terrestrial bridge of extreme tal of approximately 390 compounds from 86 l" ethnomedicine biological importance. It is one of the “hot spots” plants have been isolated, of which 160 are new l" novel compounds and occupies the fourth place among the 25 most to the literature. Most of the work reported here plant-rich countries in the world, with 13.4% en- has been the result of many international collabo- demic species. Panamanian plants have been rative efforts with scientists worldwide. From the screened for a wide range of biological activities: results presented, it is immediately obvious that as cytotoxic, brine shrimp-toxic, antiplasmodial, the Panamanian flora is still an untapped source antimicrobial, antiviral, antioxidant, immunosup- of new bioactive compounds. pressive, and antihypertensive agents. This re- view concentrates on ethnopharmacological uses Supporting information available at of medicinal plants employed by three Amerin- http://www.thieme-connect.de/ejournals/toc/ dian groups of Panama and on selected plants plantamedica Introduction are a major component of the Panamanian tropi- ! cal forest. Mosses abound in moist cloud forests as Medicinal plants remain an endless source of new well as other parts of the country. -
Extreme Precipitation in the Tropics Is Closely Associated with Long-Lived Convective Systems ✉ Rémy Roca 1 & Thomas Fiolleau 1
ARTICLE https://doi.org/10.1038/s43247-020-00015-4 OPEN Extreme precipitation in the tropics is closely associated with long-lived convective systems ✉ Rémy Roca 1 & Thomas Fiolleau 1 Water and energy cycles are linked to global warming through the water vapor feedback and heavy precipitation events are expected to intensify as the climate warms. For the mid- latitudes, extreme precipitation theory has been successful in explaining the observations, 1234567890():,; however, studies of responses in the tropics have diverged. Here we present an analysis of satellite-derived observations of daily accumulated precipitation and of the characteristics of convective systems throughout the tropics to investigate the relationship between the organization of mesoscale convective systems and extreme precipitation in the tropics. We find that 40% of the days with more than 250 mm precipitation over land are associated with convective systems that last more than 24 hours, although those systems only represent 5% of mesoscale convective systems overall. We conclude that long-lived mesoscale convective systems that are well organized contribute disproportionally to extreme tropical precipitation. 1 Laboratoire d’Études en Géophysique et Océanographie Spatiales (Université de Toulouse III, CNRS, CNES, IRD), Toulouse, France. ✉ email: [email protected] COMMUNICATIONS EARTH & ENVIRONMENT | (2020) 1:18 | https://doi.org/10.1038/s43247-020-00015-4 | www.nature.com/commsenv 1 ARTICLE COMMUNICATIONS EARTH & ENVIRONMENT | https://doi.org/10.1038/s43247-020-00015-4 ater and energy cycles are intimately linked to global The characteristics of extreme precipitating storms in the tro- Wwarming through the water vapor feedback1. Specifi- pics remain mostly qualitative, lacking in key aspects of the life cally, as temperature increases, the concentration of cycle of organized convection. -
Tropical Horticulture: Lecture 4
Tropical Horticulture: Lecture 4 Lecture 4 The Köppen Classification of Climates The climatic classifications of the greatest agricultural value are those based on the interactions of temperature and precipitation. The most widely known and used system was devised by the Austrian geographer Wladimir Köppen. It is based on temperature, precipitation, seasonal characteristics, and the fact that natural vegetation is the best available expression of the climate of a region. A distinctive feature of the Köppen system is its use of symbolic terms to designate climatic types. The various climates are described by a code consisting of letters, each of which has a precise meaning. Köppen identified five basic climates: A = Tropical rainy B = Dry C = Humid, mild-winter temperate D = Humid, severe-winter temperate E = Polar Each basic climate is subdivided to describe different subclimates, denoted by a combination of capital and small letters. The capital letters S (steppe) and W (desert) subdivide the B, or dry, climates. Similarly T (tundra) and F (icecap) subdivide the E, or polar, climates. Small letters further differentiate climates. 1 Tropical Horticulture: Lecture 4 Critics have expressed the opinion that the Köppen classification is based on too few kinds of data, and that boundaries between the various climatic regions are too arbitrary. But in spite of these objections this system has gained widespread recognition and use. Its simplicity and general adherence to vegetational zones has made it the basis for many revisions and other classifications. -
Technical Background Document in Support of the Mid-Term Review of the Global Strategy for Plant Conservation (GSPC)
Technical background document for the mid-term review of the GSPC Technical background document in support of the mid-term review of the Global Strategy for Plant Conservation (GSPC) Compiled by Botanic Gardens Conservation International (BGCI) in association with the Global Partnership for Plant Conservation (GPPC) and the Secretariat of the Convention on Biological Diversity 1 Technical background document for the mid-term review of the GSPC Contents Introduction ......................................................................................................................................5 Section 1: Progress in national / regional implementation of the GSPC ................................................6 The GSPC and National / Regional Biodiversity Strategies and Action Plans ........................................... 6 Progress in plant conservation as reported in 5th National Reports to the CBD ...................................... 7 Reviews from regional workshops ............................................................................................................ 8 Progress in China ....................................................................................................................................... 8 Progress in Brazil ....................................................................................................................................... 9 Progress in Europe .................................................................................................................................