Showing papers on "Biodiversity published in 1989"

Wildlife, Forests and Forestry: Principles of Managing Forests for Biological Diversity

Abstract: I. INTRODUCTION. 1. What is Wildlife? 2. What is Diversity? 3. What is a Forest? II. THE MACRO APPROACH, MANAGING FOREST LANDSCAPES. 4. Species Composition. 5. Age Structure. 6. Spatial Heterogeneity. 7. Edges. 8. Islands and Fragments. 9. Shores. III. THE MICRO APPROACH, MANAGING FOREST STANDS. 10. Dying, Dead and Down Trees. 11. Vertical Structure. 12. Intensive Silviculture--A. J. Kimball and M. L. Hunter, Jr. 13. Special Species. IV. SYNTHESIS AND IMPLEMENTATION. 14. Management Plans. 15. Who Pays? Appendix 1: U.S. National Policies Related to Maintaining Biological Diversity in Forests--Sarah S. Stockwell. Appendix 2: A Primer on the Metric System and Estimating Areas. Appendix 3: Diversity Indices--Catherine A. Elliott. Literature Cited and Author Index. Scientific Names and Taxonomic Index. Geographic Index. Subject Index.

Keeping Options Alive: The Scientific Basis for Conserving Biodiversity

Abstract: This book offers an overview of where the worlds species and genetic resources are located why they are valuable and a new analysis of species extinctions in tropical forests; presents a survey of the most recent findings of conservation biology; and suggests how these findings can be applied. The report ends by emphasizing the interdependence between biological diversity and human cultural diversity and the policy implications of this critical bond. The single greatest cause of species extinction is tropical deforestation where 50% of the estimated 10 million species on earth are being destroyed at the rate of 5-10% per decade. Freshwater river habitats and tropical islands are also losing species rapidly through habitat conversion and species introduction. Species can only be managed effectively by preserving habitats. The inevitable human population growth will increase demands on habitats as well as the need for biological diversity. The cost of not addressing this problem will be higher than setting management in motion. The solution is largely political; fund research put biodiversity conservation into development priorities encourage integrated regional and cross-sectoral coordination establish national priorities and promote biocultural conservation.

A role for molecular genetics in the recognition and conservation of endangered species.

Abstract: Taxonomies based on morphological traits alone sometimes provide inadequate or misleading guides to phylogenetic distinctions at the subspecies and species levels. Yet taxonomic assignments inevitably shape perceptions of biotic diversity, including recognition of endangered species. Case histories are discussed in which the data of molecular genetics revealed prior systematic errors of the two possible kinds: taxonomic recognition of groups showing little evolutionary differentiation, and lack of taxonomic recognition of phylogenetically distinct forms. In such cases, conservation efforts for 'endangered species' can be misdirected with respect to the goal of protecting biological diversity.

Threats to Biodiversity.

Abstract: When human beings emerged biodiversity was at its peak. Population growth and concurrent destruction of the environment have caused this diversity to sink to the lowest level in 65 million years. The loss of biodiversity cannot be reversed making it perhaps the most important consequence of environmental change. Biodiversity is 1 of our planets most important resources. We have not yet studied or even valued the earths plants and animals many of which hold immense potential. For example the rosy periwinkle plant (Catharanthus roseus) growing in Madagascar produces vincristine and vinblastine which effectively treat Hodgkins disease and acute lymphocytic leukemia. Yet there are 5 other Catharanthus species which scientists have not yet studied thoroughly. Habitat destruction has placed 1 species in danger of extinction. Even small perturbations in a species rich apparently stable physical environment can cause the whole ecosystem to fall. The greatest pressure on biodiversity has been on isolated and distinctly cyclic environments such as lakes and islands. For example in the 1800s complete deforestation of the small island in the South Atlantic St. Helena resulted in extinction of its unique trees and shrubs. At the present annual rate of deforestation (1%) the world is losing .2-.3% of all forest species each year (4000-6000 species). This is 10000 times greater than the naturally occurring background extinction rate. Global warming is also contributing to the loss of biodiversity especially in cold temperature and polar regions. To slow the loss of biodiversity developed and developing countries must increase taxonomic inventories and reference libraries to map species and identify hot spots for priority in conservation. Economic development must accompany species conservation particularly in countries with impoverished populations and great population growth. Sustained harvesting of natural forest products can generate more income than clear cutting and agriculture.

A Center of Crop Genetic Diversity in Western AmazoniaA new hypothesis of indigenous fruit-crop distribution

Abstract: mazonia is, arguably, the world's most important center of biodiversity. The region is also an unrecognized but important center of plant domestication. The lack of recognition may be explained by Amazonia's small contribution to world agriculture, a general lack of knowledge about Amazonian biogeography (only recently being filled in), and a bias on the part of crop evolutionists and geographers toward annual crops, such as maize (Zea mays L.), cassava (Manihot esculenta Krantz), and beans (Phaseolus spp.), because of their prominence in modern agriculture. Nicolai I. Vavilov (1951), the Russian geneticist and crop geographer who proposed the first complete world-wide model for crop genetic distribution, adhered to this bias and did not recognize Amazonia. But the geographic patterns of genetic variation in perennial fruit species support recognition of a center of crop diversity in western Amazonia. Early botanists and naturalists noted that the number and quality of fruit species increase along an eastto-west cline in Amazonia (Bates 1864, Ducke 1946, Spruce 1908, Wallace 1853); they made special reference to the pejibaye palm (Bactris gasipaes H.B.K.). Recent studies have found a complex pattern of geneticgeographic variation in this species The region is an unrecognized but important center of plant domestication

Feeding Ecology of Fruit Pigeons in Subtropical Rainforests of South-Eastern Queensland.

Abstract: In a 5-yr (1979-84) study of 6 species of fruit pigeon in lowland (dry) and upland (wet) subtropical rain forests in the Jimna and Conondale Ranges, the effects of forest phenology on pigeon abundance were investigated. The pigeons utilized 89 species of plants from 39 families of trees, palms and vines. The seasonal availability of fruit was similar in each forest type: most plant species bore crops during the wet season (Dec.-Mar.) and held crops into the early dry season (April-May); the late dry season (June-Oct.) was a time of general fruit shortage. More than 60% of the species of food plants present in upland forest were rare or absent in lowland forest. In general, each species of pigeon utilized a distinct suite of plant species in each forest type. Certain species of fig (Ficus spp.) fruited asynchronously and were the most important food for sedentary wompoo fruit-doves (Ptilinopus magnificus magnificus) in both forest types. These and other species of fig were the most important food for topknot pigeons (Lopholaimus antarcticus) and rose-crowned fruit-doves (P. regina regina) in lowland forest. An influx of flocks of up to 200 topknot pigeons into upland forest occurred each year in response to the fruiting of Archontophoenix cunninghamiana. The foraging habits of rose-crowned fruit-doves were largely opportunistic in upland forest, utilizing whatever fruit was available at particular times. White-headed pigeons (Columba leucomela) foraged solely in Olea paniculata during irregular visits to lowland forest. A regular summer influx into upland forest occurred in response to the fruiting of a vine, Piper novae-hollandiae. In each forest type, brown cuckoo-doves (Macropygia amboinensis) had a distinct foraging preference for plant species characteristic of disturbed forests; important plant families were the Solanaceae, Ulmaceae, Euphorbiaceae and Araliaceae. Superb fruit-doves (P. superbus) were seldom found in either forest type.

Occurrence of Birds in Relation to Plants in a Sub-Tropical City

Abstract: Habitat use by birds in suburbs of Brisbane, Queensland was studied during winter, at sites with relatively similar habitat features near to (0.25-0.5km) and far from (2-3km) a eucalypt forest. Variation in other factors was restricted. Distance from native forest was found to have little influence on abundance of birds in suburban habitats. House sparrows and willie wagtails were relatively more abundant at the far sites. Most of the more common forest-dwelling species were not common in either near or far suburbs. There was little similarity in relative abundance of bird species between the forest and either the near or far suburbs. A similarity in species diversity and positive correlations in species abundance between near and far sites indicate that most species are either forest or suburb 'specialists'. Native birds were more selective in their choice of plant category than introduced birds, and had a high probability of using certain native and exotic plant species, and a lower probability of using others. Although generally more abundant, introduced birds did not have a high probability of using any plant genus or type. Birds in the area studied are probably altering their patterns of habitat use in response to changes in food availability.

Algal species diversity and dominance along gradients of stress and disturbance in marine environments

Abstract: Data on algal species diversity from six areas along the Swedish coast, differing in salinity, length of growth period and grazing pressure were used to test two main predictions arising from the hump-backed model of species diversity (Grime 1973; Connell & Slatyer 1977; Tilman 1982; Fuentes & Jaksic 1988).

Tropical deforestation and species endangerment: the role of remote sensing

Abstract: Initial results of a pilot study to link remotely-sensed information on tropical forest loss to field-based information on species endangerment are reported here. LANDSAT multispectral scanner (MSS) imagery from 1973 and 1988 were used to estimate net forest removal (29% of forest area), regrowth (7% of forest area, including possible artifactual errors), and forest edges in Mabira Forest in southeastern Uganda during the 15-year period. Of the forest remaining, the percentage that was heavily disturbed increased from 18% to 42%. This change in forest density was observable with the MSS imagery. The total forest edge-to-area ratio (including edges interior to the forest boundary) increased by 29% over the period. Although four distinct types of closed tropical forest, based on structure or dominance, could be recognized on the ground, the types could not be distinguished by differences in spectral reflectance in the four MSS bands. Closed tropical forest could be readily distinguished from exotic conifer plantations, banana plantations, and other non-forest vegetation types. Field measurements in Mabira and other Ugandan rain forests, and in rain forest isolates on the Atherton Tableland of North Queensland, are being made to relate changes in forest fragmentation to resulting changes in species abundance, structural form of the forests, and morphological diversity of target populations. Possible applications of conservation biology theory and modeling to these data are briefly discussed.

Diversity measurements in shrubland communities of Galicia (NW Spain)

Abstract: Diversity was studied in 10 communities, including the understory of native oak woodland, planted woodlands (pine and eucalypt), and shrublands in the strict sense (heathlands, broom shrublands, gorse shrublands). In each community, species richness, diversity, dominance and evenness were analysed. Differences were observed among communities with regard to species composition, richness in annual herbs, perennial herbs and shrubs, dominant plant families (Ericaceae, Papilionaceae) and diversification of shrub species. The possible relations between environmental stress and/or human influences on differences in diversity are discussed.

Status Assessment of Biodiversity Protection

Abstract: Crumpacker et al. (1988) presented a case for using the representation of potential natural vegetation (PNV) types (Kuchler 1964) on federal and Indian lands to identify unprotected natural ecosystems. We agree that a systems-level strategy is the most practical way to preserve biological diversity (Scott et al. 1987). The current emphasis on the recovery of endangered species and communities focuses limited conservation funding on a few of Earth's 30,000,000 species. The rate of habitat loss, especially in the tropics, has driven the extinction rate to unprecedented levels. The cost of reacting to these increasingly numerous crises already exceeds the global conservation budget. A number of authors (Ehrlich & Ehrlich 1981; Hutto et al. 1987; Scott et al. 1988; Norton 1988) have pointed out that saving groups of species in self-maintaining ecosystems offers a

The Vertebrate Fauna of Broombush Melaleuca-Uncinata Vegetation in Northwestern Victoria, With Reference to Effects of Broombush Harvesting

Abstract: The vertebrate fauna of broombush Melaleuca uncinata vegetation in north-western Victoria was assessed by censusing in marked quadrats, trapping and wide-ranging observations. Most species of vertebrates known to occur in mallee shrublands in Victoria we recorded in broombush (those recorded included four amphibian, 42 reptile, 126 bird and 18 mammal species). This high diversity resulted from a substantial variation in vertebrate (particularly reptile and bird) species composition between broombush of differing ages (0-80 years). Some floristic variation between broombush stands and the local presence within these stands of particular plant species (notably Triodia irritans and Banksia ornata) also added to vertebrate species diversity. Locally, broombush patches were characteristically simple in structure and of low floristic diversity. Bird species diversity and density were low (<3 individuals per ha). Broombush is being harvested at an accelerating rate in Victoria. The effects of this industry on vertebrates generally are minor. No vertebrate species is restricted to broombush, and most vertebrate species recorded in this survey were found in harvested areas. Nonetheless, broombush is an important habitat for several species (e.g. Ctenophorus pictus, Ctenotus uber, C. brooksi, Leipoa ocellata, Pachycephala rufogularis, Psophodes nigrogularis, Drymodes brunneopygia, Cercartetus lepidus and Notomys mitchelli). Information on the ecology of most species of vertebrates living in the mallee is very limited, and some species may be affected by broombush cutting through a decrease in area of habitat of suitable age.

The Mexican tropical deciduous forest of Baja California Sur: a floristic and structural approach

Abstract: A quantitative study is presented of the tropical deciduous forest located in the Sierra de La Laguna in the southern part of the peninsula of Baja California, Mexico with data on structure, species composition, diversity, density, and abundance of perennial plants. 4 study plots were selected to represent the predominant geomorphologic units, and to include topographic and climatic variations reflected by the distribution of this vegetation on the lowlands of slopes facing the Gulf of California and the Pacific Ocean. 25 families containing 67 perennial species were found on the lowlands, with Leguminosae, Cactaceae, and Euphorbiaceae best represented. A high family diversity was found in the plots, but there was a low number of species per family. Dissimilarities between sites were found to be reflected significantly in growth-form abundances as well as in structural features and species diversity. Results show that the xeric environment, the low number of species, and the high incidence of dominant shrub species confer the vegetation of the lowlands simpler structural traits than those described for other tropical dry forests.

A classification of the deciduous forest of eastern North America

Abstract: Data from 300 forest stands, scattered over 29 states within the eastern North American deciduous forest, were subjected to detrended correspondence analysis (DCA) and two-way indicator species analysis (TWINSPAN) in an effort to identify classifiable units. Most species are widespread which provide a great deal of continuity in the vegetation. The deciduous forest can be divided into three forest regions: (1) northern, (2) central and (3) southern. The northern region corresponds to the hemlock-white pine-northern hardwood forest of Braun (1950). The central region includes the beech-maple and oak-hickory forests. The beech-maple as identified here includes the mixed mesophytic, beech-maple, maple-basswood and about half of the western mesophytic forests of Braun (1950). The oak-hickory includes Braun's oak-hickory, oak-chestnut and about half of the western mesophytic forests. The southern region coincides with the southern mixed hardwood forests.

Biological Diversity in Surface Mined Areas After Reclamation

Abstract: Diversity of plants on reclaimed surface mine areas of rock phosphate mines at Maldeota (18 km from Dehra Dun) has been evaluated. Results of the study shows that diversity of plants has increased significantly after 4 years of reclamation and is even higher than the adjoining natural areas as well as lower and upper Himalayan moist temperate forest (sub-group 12 Cl and 12 C2).

Diversity in intertidal communities with special reference to the Corallina officinalis community

Abstract: Species richness is distinguished from the evenness of apportionment of individuals among species. Confusing these concepts in "diversity indices" is condemned. Diversity should be related to specified taxa and habitats. Two kinds of biological diversity are distinguished - gradient diversity and mosaic diversity. Of various proposed causes of high diversity, niche creation through physical and biological heterogeneity is emphasised. It is shown that when there is a mutualistic relationship between species higher species richness can be achieved without loss of stability. Examples of such high diversity ecosystems include the phytal community of temperate tidepool algae. Observations on the phytal community associated with Corallina officinalis indicate that increasing the abundance of a dominant epiphvtic serpulid, Spirorbis corallznae, correlates with higher numbers and greater species richness of the phytal. It is thought that the increase in the numbers and variety of spaces and surfaces created by settling spirorbids is the feature that offers more niches to the associated fauna.

A growing sphere of knowledge

Abstract: Biodiversity. Edited by E. O. Wilson. National Academy Press: 1988. Pp.521. Pbk $19.50. Distributed in Europe by Wiley, £16.80. To be published in hardback next month, £27.85, $32.50.

Taxonomic studies on the genera aporophlebus, eumicrosoma and platytelenomus of japan and korea (hymenoptera, scelionidae, telenominae)

Abstract: Aporophlebus, Eumicrosomu and Platytelenomus of the subfamily Telenominae of the family Scelionidae are reported from Japan and Korea. Four new species, Eumicrosoma paulum Ryu, Pkztytelenomus brew& Ryu, P. convexxs Ryu and P. elongates Ryu are described. The followings are new records: Eumicrosoma from Korea, Eumicrosoma phaeax (Nixon) from Japan and Korea, and Platytelenomus danubialis Szelenyi from Japan. Asolcus minor Watanabe is transferred to Aporophlebus and is recorded from Korea for the first time. Genus Aporophlebus Kozlov, 1970 Type-species : Aporophlebus aporus Kozlov, 1970. Aporophlebus Kozlov, 1970, Ent. Obozr., 49 : 216. Eight species of Aporophlebus are known from the Palaearctic Region by Kozlov ; from USSR (1972), Western Europe (1970) Moldavia (1970), Mongolia (1972), Turkmenia (1972) and Tadzhikistan (1972). Information on the occurrence of Aporophlebus in Japan and Korea was given by Masner (1976). So far as we know, this genus is represented by one species, A. minor, in Japan and Korea, which parasitizes the eggs of the Plataspidae (Heteroptera). This genus is characterized as follows : Head often elongate particularly in buccal region. Frons and cheeks with longitudinal (often fan-like) keels or striae. Eyes with minute hairs. Antennae ll-segmented in female, 12segmented in male. Mesoscutum in posterior half with or without traces of notauli ; mesoscutum and scutellum convex, arched as seen from side, with sculpture. Postmarginal vein usually short, as long as stigma1 vein, rarely longer. First metasomal tergum often light colored, orange-yellow.

Water Relations of Obligate Riparian Plants as a Function of Streamflow Diversion on the Bishop Creek Watershed

Abstract: We investigated the water relations of obligate riparian plants on paired diverted and undiverted reaches on Bishop Creek, Eastern Sierra Nevada. Riparian plants on diverted reaches had reduced stomatal conductance and water potential compared to plants on undiverted reaches in a dry year, but not in a high runoff year. Juvenile plants on diverted reaches had reduced stomatal conductance and lower midday water potentials relative to surrounding mature trees, a trend that was not observed on undiverted reaches. Plants on diverted reaches possessed significantly smaller, thicker leaves and a reduced total leaf area relative to trees on streamside reaches. Reduced community leaf area and effective stomatal control of water loss may allow riparian corridors on diverted reaches to retain their canopies in low runoff years. However, a long term consequence of partial streamflow diversion may be selective mortality of juvenile plants because of the elimination of floods and high flows.