Plant Conservation Challenges in the Bahama Archipelago

The Bahamian archipelago has a rich flora with 89 endemic species. An international symposium held at Nassau in October 2012 to celebrate the 30th anniversary of the publication of the “Flora of the Bahama Archipelago” provided a forum to discuss plant conservation issues on these islands. This article builds on conclusions from this symposium and results from joint plant conservation research projects among the authors. The two main conservation challenges for these islands are: (1) environmental uncertainties derived from global warming and associated sea level changes and (2) the need for increased plant conservation awareness among the predominant urban population of the archipelago. Legal tools and biodiversity international agreements in place for The Commonwealth of the Bahamas can facilitate mechanisms for effective plant conservation. Further legal developments need to be established in The United Kingdom Overseas Territory of The Turks and Caicos Islands. There is an urgent need to redevelop the Botanic Garden of Nassau and designate it as the national botanic garden of The Bahamas. Further research related to the taxonomy, biology, conservation status, and distribution of the endemic species is urgently needed. Research initiatives pertinent to the detrimental effect and biology of invasive species are also lacking. The heterogeneous environments and uneven distribution of human populations across the archipelago are major challenges for conservation. Finally because of the political and economic status of The Bahamas and The Turks and Caicos, conservation agencies from the archipelago do not have easy access to international or British/European Union funds for global conservation initiatives.     

!Kung spatial organization: An ecological and historical perspective

The ecological and social bases of spatial organization among hunters and gatherers are examined. After criticizing the patrilocal band model of social organization, the author documents the flexible, nonterritorial groupings of the !Kung Bushmen of Botswana and relates them to rainfall and surface water scarcity and variability. The paper goes on to consider the effects of extra-Bushman contacts on the breakdown of sociospatial organization and finds that the observed flexibility occurred in both the pre- and the postcontact periods. The final section attempts to relate the analysis to general issues. Three areas that need further work if a more valid model of hunter spatial organization is to be developed are the problems of time perspective in research, adaptation to long-term climatic variability, and critical thresholds of population density.     

Invertebrate communities delineate hydro-ecoregions and respond to anthropogenic disturbance in East-Amazonian streams

Many tropical regions lack models predicting the biological and environmental conditions expected in any given area, thus precluding the implementation of reference condition-based water policies. We focused on streams of French Guiana, and tested two predictions: geomorphology determines ecological sub-regions that have typical invertebrate communities, and diversity declines as anthropogenic pressure increases. Sixty-five stream sites were sampled for benthic invertebrates and physical–chemical variables across various watersheds. We used the Self-Organizing Map algorithm (neural network) to model relationships between invertebrate communities and environmental variables. Sites characterized by invertebrate communities clustered into two major subsets matching French Guiana’s hydro-ecoregions: the coastal alluvial plain characterized by recent sediment and low elevations, and the Guiana Shield characterized by an eroded rocky substrate and dense rainforests. Changes in community composition, and to a lesser extent taxonomic richness within each sub-region revealed ecological impacts of gold mining and logging, further clustering hydro-ecoregions into subsets of reference and impaired sites. Further analyses would, however, be needed to identify tipping points between natural and disturbed states, especially in remote headwater streams where gold mining had the harsher impact upon freshwater diversity, making upstream communities resembling the most downstream impacted ones.     

Alteration in the zooplankton community of a fly ash treated lake

The zooplankton community in Lake Charles East, Indiana, was sampled from June, 1974 through September, 1977 as part of a lake restoration study. About 1.8 × 10⁴ kg of lime and 1.8 × 10⁶ kg of ponded fly ash were added to the lake during May through August, 1975 to precipitate phosphate and seal the sediments. Annual mean species number (5.2–11.3) and annual mean species diversity (H′, 0.9–1.3) were highest in 1976, the first year after treatment. By the second post-treatment year these variables had returned to pretreatment levels. Prior to treatment Cladocera were dominant during fall and early winter (Sept.–Dec. 1974), with Copepoda dominant in late winter and spring (Jan.–May 1975). After treatment Cladocera were dominant throughout the fall and winter (Nov. 1957–May 1976). Copepoda were again dominant in August 1976. The short term effect of the treatment appeared to be termination of the latter part of the copepod annual cycle through elimination of aestivating copepodites in the summer and increased abundance of Cladocera during the winter and spring immediately following treatment. Community composition one year after treatment was similar to that observed prior to treatment.     

Options and problems in environmental management and evaluation

Although logical compromise agreement between all the conflicting users of the sea seems the most obvious way to protect marine life, we have in practice mainly ad-hoc restrictions aimed at protecting habitats or species, or at trying to prevent chemical/physical deterioration of the environment. The establishment of reserves on biological rather than touristic grounds necessitates consideration of the criteria, appropriate to marine life, that should be used. Successful reserve management or species protection measures depend upon distinguishing between natural and man-made changes, an ability that can be enhanced in part by appropriate disturbance experiments. Anti-pollution measures have centred upon effluent input rather than biological effect in the field, with “acceptable discharge levels” being based upon lethal and sub-lethal experimental effects. But the ultimate criteria of environmental well-being are ecological responses at the population and community levels where, unfortunately, many natural and man-made influences produce similar changes. Knowledge of community dynamics and a resulting ability to discount natural events require long-term studies and are slow to accumulate. Thus while short-term sublethal studies proliferate many ecological data remain uninterpretable except in localities of gross and obvious pollution (including tanker accidents). The scarcity of sub-lethal and ecological effects in the field is even supplemented by ecological changes that are contrary to expectations based on pollution loadings. Is this because ecological expertise is still inadequate, or because experimental and environmental loading data grossly overstate the risks and are largely irrelevant at the community level? Can we assume that fears of chronic pollution are unfounded or must we intensify our efforts? If the latter, in which direction?     

Dynamics of populations ofBiomphalaria glabrata and the von forerster equation

Changes in time of populations ofBiomphalaria glabrata due to changes in the rate of infection bySchistosoma mansomi are investigated. This is done by applying Von Foerster equations with boundary conditions derived from experiment. The resulting equation is solved in some simplified cases and applications of the formalism to ecological problems is suggested.     

High Fungal Diversity and Abundance Recovered in the Deep-Sea Sediments of the Pacific Ocean

Knowledge about the presence and ecological significance of bacteria and archaea in the deep-sea environments has been well recognized, but the eukaryotic microorganisms, such as fungi, have rarely been reported. The present study investigated the composition and abundance of fungal community in the deep-sea sediments of the Pacific Ocean. In this study, a total of 1,947 internal transcribed spacer (ITS) regions of fungal rRNA gene clones were recovered from five sediment samples at the Pacific Ocean (water depths ranging from 5,017 to 6,986 m) using three different PCR primer sets. There were 16, 17, and 15 different operational taxonomic units (OTUs) identified from fungal-universal, Ascomycota-, and Basidiomycota-specific clone libraries, respectively. Majority of the recovered sequences belonged to diverse phylotypes of Ascomycota (25 phylotypes) and Basidiomycota (18 phylotypes). The multiple primer approach totally recovered 27 phylotypes which showed low similarities (≤97 %) with available fungal sequences in the GenBank, suggesting possible new fungal taxa occurring in the deep-sea environments or belonging to taxa not represented in the GenBank. Our results also recovered high fungal LSU rRNA gene copy numbers (3.52?×?10⁶ to 5.23?×?10⁷copies/g wet sediment) from the Pacific Ocean sediment samples, suggesting that the fungi might be involved in important ecological functions in the deep-sea environments.     

A comparative approach to the organization of vocal signals in noctural prosimians

Vocalizations and corresponding behavior patterns were recorded inGalago demidovii (Lorisidae), Microcebus murinus, andCheirogaleus medius (Cheirogaleidae). Physical characteristics of the calls were analyzed and calls correlated with their behavioral context. Based on these correlations an «advertisement» call can be identified in all three species. Interspecific comparison suggest that within the Prosimian suborder there are at least two different evolutionary pathways in the organization of this call and of the vocal repertoires in general. The Lorisid speciesG. demidovii conveys acoustic information mainly in pulsed calls, leading to an extreme amplitude-modulation. Individual characteristics are in temporal patterns of calls.C. medius andM. murinus, the Cheirogaleid species, use tonal calls and encode individual characteristics in frequency patterns. Despite the fundamental similarity in the call-structure of the two Cheirogaleid species different adaptations can be found to meet different ecological needs.     

Plants and environment: Two decades of research at the Canberra phytotron

The research carried out at the Canberra phytotron, CERES, during the first twenty years of its operation is reviewed as a case study of the opportunities, problems and value of phytotron research. The climatic responses of a large number of species, both wild and domesticated, are examined as well as those of fungal and viral pathogens and rhizobial symbionts. Some aspects of the design of CERES are briefly considered, and a few aspects of the variation between plants in climatic response, with the C₄ photosynthetic syndrome taken as a case history of the linkages between biochemistry, anatomy and response to climate. Research in ecology, forestry, horticulture, plant pathology, rhizobial microbiology, anatomy and ultrastructure—and specific aspects of biochemistry, plant nutrition and genetics—are reviewed to indicate the range of botanical disciplines which can profit from access to a phytotron. The ecological research at CERES, much of it with trees and perennial grasses, particularly highlights the value of combining field and phytotron studies. Work on seed proteins, hybrid vigor and plant growth regulators is also reviewed. The next part of the paper considers the effects of the major environmental factors, temperature, daylength, irradiance, atmospheric CO₂ level and water stress, together with their interactions and the problems of correlating phytotron and field responses. The effect of these factors on the various processes of growth and development are considered, and the stages of development most sensitive to them. An evolutionary perspective on yield potential is then discussed, leading to a consideration of photosynthesis, translocation, partitioning and storage organ growth as yield-determining processes. The final part considers the uses of phytotrons in agricultural, horticultural and forestry research, in terms of examples from work at CERES on the manipulation of breeding systems, the clarification of plant breeding objectives, the use of phytotron conditions for selection, the prediction of adaptation and spread, and models for yield prediction and pest management. Several areas requiring more attention are identified, and some conclusions are drawn on the value of access to a phytotron such as CERES for botanical research of many kinds.     

Identifying monitoring gaps for amphibian populations in a North American biodiversity hotspot,the southeastern USA

I review the primary literature to ascertain the status of amphibian monitoring efforts in the southeastern USA, a “hotspot” for biodiversity in North America. This effort revealed taxonomic, geographic and ecological disparities in studies of amphibian populations in this region. Of the species of anurans and caudates known to occur in the Southeast, 73.8 and 33.3 %, respectively, have been monitored continuously for at least 4 years. Anurans are generally shorter-lived than are caudates and, thus, have been studied for the equivalent of at least one population turnover more than have caudates. The percentage of species (of those occurring in a given state) monitored continuously for at least 4 years was lowest for Alabama and Mississippi and highest for Florida for both taxa. The vast majority of studies (69.6 %) were conducted on species that inhabit natural freshwater wetlands, in contrast to other aquatic and terrestrial habitats. Species considered threatened by the International Union for Conservation of Nature comprised only 7.7 % of 65 species that have been studied consistently. The majority of comparative studies of contemporary versus historical occurrences were potentially biased by the use of “presence-only” historical data and resurveys of short duration. Other issues, such as inadequate temporal and spatial scale and neglect of different sources of error, were common. Awareness of these data gaps and sampling and statistical issues may help facilitate informed decisions in setting future monitoring priorities, particularly with respect to species, habitats and locations that have been largely overlooked in past and ongoing studies.     

Litterfall and nitrogen turnover in an Amazonian blackwater inundation forest

In 1976/77 energy flow and nutrient cycling in an Amazonian blackwater inundation forest were studied. The major part of the litter biomass turnover occurred during the emersion phase. 95% decomposition rate for nitrogen was measured with 15 mm mesh litter bags and was 4.7 years. Over 30 per cent of the annual leaf-fall was decomposed by soil-dwelling arthropods.     

Pretraining and learning: Are “adaptable” monkeys “bright”?

Two groups of rhesus (Macaca mulatta),two groups of cynomolgus (M. fascicularis),and one group of stumptailed monkeys (M. arctoides)were adapted to testing in the Wisconsin General Test Apparatus using a standardized procedure that produced an objective measure of the speed of adaptation (pretraining). Four of the groups were then given standard object-discrimination learning-set training. The fifth group, one of the groups of rhesus monkeys, was given delayed response training before the learning-set training and delayed matching-to-sample learning-set training after. Only performance on the delayed response task was correlated with speed of pretraining. The results suggest that differences in pretraining performance reflect primarily emotional and/or temperamental differences, whereas differences in learning-set performance reflect primarily differences in cognitive functioning.     

Folk Food Webs and the Role of Praxis in Substantive Ecological Knowledge

In the second half of the 20th century, investigations of indigenous environmental knowledge have been the subject of broader anthropological debates over how knowledge and experience are formed. Many such approaches have focused on environmental nomenclature and taxonomy, or what Roy Ellen has called “formal lexical knowledge” (1999). Such knowledge is readily available to an ethnographer and also more easily transmitted through language between subjects. These characteristics of formal lexical knowledge have led to considerable attention given to differences in environmental knowledge between cultures and have possibly resulted in the inflation of the efficacy of language in forming knowledge. However, if a different form of environmental knowledge is examined are there differences that emerge within communities and other processes beyond symbolic systems that shape knowledge? To address these questions, individuals in two Balinese agricultural communities were asked to construct food webs by linking photos of plant and animal species according to ecological interaction. The results showed significant variation in subjects’ knowledge by gender, which corresponds to labor experience in Balinese wet rice agricultural systems. By shifting attention toward emic models of ecological interactions, this article attempts to demonstrate (1) that environmental knowledge differs within a single community; and, (2) the role of labor experience or praxis has in forming environmental knowledge.     

Comparison of biochemical and molecular genetic approaches for identification of environmental strains

In order to confirm the taxonomic position of environmental strains determined based on their biochemical, cultural, and morphological characteristics, molecular genetic identification was carried out. A number of problems in identification of microorganisms were shown to be associated with contamination of the cultures in the course of isolation. Advantages of a comprehensive approach—combining 16S rRNA gene sequencing with a set of biochemical, cultural, and morphological parameters—for identification of microorganisms isolated from environmental objects and clinical samples are discussed.     

Coppice swidden fallows in tropical deciduous forest: Biological,technological, and sociocultural determinants of secondary forest successions

Secondary succession in tropical deciduous forest is often characterized by vegetative reproduction, or coppicing. Coppicing is also observed in forest sites that are disturbed by farming activity. This observation raises questions about the role of established management practices in determining the succession of vegetation on farmsites once they are abandoned to fallow. To what extent is the coppicing succession the result of specific aspects of swidden farming technology and management? And what variations in coppice successions occur in swidden sites following deviations from the standard farming practice? In research on swidden farming among the Susu of Sierra Leone, I examined the successional pathway in an age series of forest fallow sites. I show that the standard pattern of minimal cultivation favors the coppicing of felled trees in the subsequent fallow periods. By contrast, deviation from this pattern results in stump deaths and favors the invasion of fallow sites by grasses and vegetatively reproducing pioneer trees from the savanna. Variations in the environmental outcome of disturbance to plant communities, then, are the result of interactions between processes of tropical tree reproduction and the agricultural practices of local farmers.     

Histochemical and biochemical evidence for the presence of microbodies in Phytophthora palmivora

Using the diaminobenzidine (DAB) reaction catalase activity could be demonstrated histochemically in cytoplasmic structures of Phytophthora palmivora bearing general ultrastructural features of microbodies. These socalled U-bodies sediment together with the catalase activity in Ficoll-Sorbitol-Sucrose gradients following prior purification by differential centrifugation.     

Genetic variation in the activity of the histidine catabolic enzymes between inbred strains of mice: A structural locus for a cytosol histidine aminotransferase isozyme (Hat-1)

Variation in activity of the main histidine catabolic enzymes (histidase, urocanase, and aminotransferase) has been surveyed using inbred strains of mice (C57BL, DBA, Peru, SM, and SWR). Some variation was found in the activity of all enzymes, but only in the case of cytosolic histidine aminotransferase was it greater than twofold (SM 3.3-fold greater than C57BL). The divergent strains for the activity of this enzyme were crossed and the F ₁ 's were backcrossed; the segregation analysis indicated a single locus with additively acting alleles (designated Hat-1: a allele SM, b allele C57BL). Cytosolic histidine aminotransferase differed in heat stability between SM and C57BL, indicating that Hat-1 is a structural locus. The conflict in the biochemical literature (Morris et al., 1973; Noguchi et al., 1976a, b) over the number and subcellular distribution of the histidine aminotransferase isozymes is partly resolved by the acquisition of a variant at the Hat-1 locus. Hat-1 affects the cytosolic form but not the mitochondrial form of the enzyme. Purification and analysis of the isozymes of histidine aminotransferase from livers of C57BL and SM mice will further clarify the situation.