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Remaining Areas (remaining + area)
Selected AbstractsThe use of a geographical information system for land-based aquaculture planningAQUACULTURE RESEARCH, Issue 4 2002Ian McLeod Abstract Site selection for aquaculture planning is a complex task involving the identification of areas that are economically, socially and environmentally suitable, available to aquaculture and commercially practicable. This paper reports upon a study into the use of a geographic information system (GIS) to assist in aquaculture planning. Using a case study in the site selection for land-based shrimp farming within the Australian coastal zone, we demonstrate that a GIS has potential to assist aquaculture planning. Our analysis is based on a sequential, two-stage approach. The first stage eliminates the grossly unsuitable portion of the study area through a preselection with low resolution, cheap and easily available data. The second stage then focuses on and ranks the remaining area using high resolution, possibly more expensive data. Finally, we use the GIS to present the results of the analysis in an easily accessible form. [source] Assessing the Effectiveness of Reserve Acquisition Programs in Protecting Rare and Threatened SpeciesCONSERVATION BIOLOGY, Issue 6 2006WILL R. TURNER Lake Wales Ridge (Florida); especies en peligro; índice de protección; Lista Roja IUCN; matorral Abstract:,Measuring the effectiveness of reserve networks is essential to ensure that conservation objectives such as species persistence are being met. We devised a new approach for measuring the effectiveness of land conservation in protecting rare and threatened species and applied it to an ecosystem of global significance. We compiled detailed global distributional data for 36 rare and threatened plants and animals found in the Lake Wales Ridge ecosystem in central Florida (U.S.A.). For each species, we developed a set of protection indices based in part on criteria used to categorize species for the World Conservation Union's Red List. We calculated protection indexes under three different conservation scenarios: a past scenario, which assumed recent, major land-acquisition efforts never occurred; a current scenario, which assumed no additional areas are saved beyond what is currently protected; and a targeted scenario, which assumed all of the remaining areas targeted for protection are eventually acquired. This approach enabled us to quantify the progress, in terms of reduced risk of extinction, that conservationists have made in protecting target species. It also revealed the limited success these land-acquisition efforts have had in reducing those extinction risks associated with loss of habitat or small geographic ranges. Many species of the Lake Wales Ridge will remain at high risk of extinction even if planned land-acquisition efforts are completely successful. By calculating protection indexes with and without each site for all imperiled species, we also quantified the contribution of each protected area to the conservation of each species, enabling local conservation decisions to be made in the context of a larger (global) perspective. The protection index approach can be adapted readily to other ecosystems with multiple rare and threatened species. Resumen:,La cuantificación de la efectividad de las redes de reservas es esencial para asegurar que objetivos, como la persistencia de especies, se cumplan. Diseñamos un nuevo método para medir la efectividad de la conservación de tierras en la protección de especies raras y amenazadas y lo aplicamos a un ecosistema de importancia global. Compilamos datos detallados de la distribución global de 36 especies raras y amenazadas de plantas y animales que se encuentran en el ecosistema de la Lake Wales Ridge en el centro de Florida (E.U.A.). Para cada especie desarrollamos un conjunto de índices de protección basado parcialmente en criterios utilizados para clasificar especies para la Lista Roja de la Unión Mundial para la Naturaleza. Calculamos los índices de protección bajo tres escenarios de conservación distintos: un escenario pasado, que asumía que los esfuerzos recientes de adquisición de tierras nunca ocurrieron; un escenario actual, que asumía que no se protegen áreas adicionales a las ya conservadas; y un escenario deseado, que asumía que todas las áreas consideradas para ser protegidas son adquiridas eventualmente. Este método nos permitió cuantificar el progreso, en términos de la reducción del riesgo de extinción, en la protección de las especies obtenido por conservacionistas. También reveló el éxito limitado de los esfuerzos de adquisición de tierras en la disminución de los riesgos de extinción asociados con la pérdida de hábitat o con rangos geográficos pequeños. Se pronosticó que muchas especies de la Lake Wales Ridge permanecerán en alto riesgo aun si los esfuerzos de adquisición de tierra planificados son completamente exitosos. Al calcular los índices de protección con y sin cada sitio para todas las especies en peligro, también cuantificamos la contribución de cada área protegida a la conservación de cada especie, lo que permite que las decisiones de conservación se tomen en el contexto de una perspectiva mayor (global). El método del índice de protección se puede adaptar fácilmente a otros ecosistemas con múltiples especies raras y amenazadas. [source] Q-Switched Ruby Laser Treatment for Postsclerotherapy HyperpigmentationDERMATOLOGIC SURGERY, Issue 7 2000Alireza Tafazzoli Background. One of the most common adverse sequelae of sclerotherapy is cutaneous hyperpigmentation. Objective. We used the Q-switched ruby laser to treat postsclerotherapy hyperpigmentation. Methods. Eight patients developed pigmentation lasting more than 1 year (1,2 years on average) after sclerotherapy treatment for reticular and telangiectatic veins in the legs ranging in size from 0.2 to 4 mm in diameter. All patients were treated with a Q-switched ruby laser at 694 nm, 4 mm beam size, and fluence range of 5.6,10.5 J/cm2. Results. Ninety-two percent of lesions lightened after treatment. There was significant (75,100%) resolution of hyperpigmentation in 58% of treated areas, 25% improvement in 33% of treated areas, and no improvement in the remaining areas. Conclusion. Our impression is that given a choice of lasers, the Q-switched ruby laser provides the greatest efficacy for treating postsclerotherapy hyperpigmentation. [source] Review article: from 1906 to 2006 , a century of major evolution of understanding of gastro-oesophageal reflux diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2006J. DENT Summary Background Our understanding of gastro-oesophageal reflux disease has undergone significant changes over the last century. Aim To trace the rise in understanding of gastro-oesophageal reflux disease and highlight remaining areas of uncertainty. Methods Literature review. Results In 1906, Tileston published his observations on ,peptic ulcer of the oesophagus'. Winkelstein, in 1934, first correlated symptoms of heartburn with acid regurgitation and reflux oesophagitis. In 1946, Allison described hiatus hernia as a causal factor in the development of gastro-oesophageal reflux disease. In 1958, Bernstein and Baker showed a direct relationship between oesophageal acidification and heartburn in patients with gastro-oesophageal reflux disease, irrespective of endoscopic findings, leading to the recognition of non-erosive gastro-oesophageal reflux disease. In the 1980s, continuous recordings of the lower oesophageal sphincter showed that episodes of reflux were related to transient relaxations of lower oesophageal sphincter tone. There is now increasing recognition that gastro-oesophageal reflux disease arises from the interaction of several anatomical and physiological factors. A turning point in the medical treatment of gastro-oesophageal reflux disease came with the introduction of the first proton pump inhibitor, omeprazole, in 1989. Conclusions Future efforts need to identify the multifactorial interactions of gastro-oesophageal junction anatomy and physiology in patients with gastro-oesophageal reflux disease. Increased understanding of the disease will guide development of new therapies. [source] Paraquat and sustainable agriculturePEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 4 2004Richard H Bromilow Abstract Sustainable agriculture is essential for man's survival, especially given our rapidly increasing population. Expansion of agriculture into remaining areas of natural vegetation is undesirable, as this would reduce biodiversity on the planet. Maintaining or indeed improving crop yields on existing farmed land, whether on a smallholder scale or on larger farms, is thus necessary. One of the limiting factors is often weed control; biological control of weeds is generally of limited use and mechanical control is either often difficult with machinery or very laborious by hand. Thus the use of herbicides has become very important. Minimum cultivation can also be important, as it reduces the power required to work the soil, limits erosion and helps to maintain the organic matter content of the soil. This last aspect helps preserve both the structure of soil and its populations of organisms, and also sustains the Earth's soil as a massive sink for carbon, an important consideration in the light of global warming. The introduction of the bipyridinium herbicide paraquat in the early 1960s greatly facilitated weed control in many crops. Paraquat has the unusual property of being active only by direct spray onto plants and not by uptake from soil in which strong binding deactivates it. Together with its rapid action in light in killing green plant tissue, such properties allow paraquat to be used in many crops, including those grown by low-tillage methods. This paper reviews the ways in which agricultural systems have been and are being developed to make use of these properties, and provides a risk/benefit analysis of the world-wide use of paraquat over nearly 40 years. Copyright © 2004 Society of Chemical Industry [source] Linking vegetation heterogeneity and functional attributes of temperate grasslands through remote sensingAPPLIED VEGETATION SCIENCE, Issue 1 2008Roxana Aragón Abstract Question: How are plant communities of the Flooding Pampa grasslands spatially distributed? How do canopy dynamics of the different communities vary among seasons and years? Location: Buenos Aires province, Argentina. Methods: We characterized the distribution of communities through a supervised classification based on four Landsat 5TM images. We sampled species composition of 200 sites, with 130 of them corresponding to natural communities. Of the sampling areas 60% were used to classify, and the remaining areas to assess classification accuracy. We characterized the seasonal and interannual variability of canopy dynamics using NDVI (Normalized Difference Vegetation Index) data provided by MODIS /Terra images. Results: Overall accuracy of the classification was satisfactory. The resulting maps showed a landscape formed by a matrix of extended lowlands with small patches of mesophytic and humid mesophytic meadows. The October scene (near the peak of productivity) was particularly important in discriminating among communities. The seasonal pattern of NDVI differed among communities and years. Mesophytic meadows had the highest NDVI mean and the lowest interannual coefficient of variation, halophytic steppes had the lowest mean, and vegetated ponds were the most variable. Conclusions: These grasslands have a fine-grained heterogeneity at the landscape scale. Each plant community has distinct seasonal and interannual canopy dynamics. These two features of grassland structure and functioning represent key information for rangeland management that may be obtained through a combination of minor field sampling and remote sensing. [source] Satellite radar observation of tropical peat swamp forest as a tool for hydrological modelling and environmental protectionAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2007Dirk H. Hoekman Abstract 1.Tropical peat swamp forests may contain as much as 20% of the global soil carbon stock. They are threatened by large-scale deforestation and canal drainage. Oxidation and forest fire cause enormous carbon emissions. Most remaining areas are located in Indonesia. These are becoming increasingly important for maintaining biodiversity. 2.Time series of historical JERS-1 SAR data reveal the extent and nature of recent disturbances, such as those caused by excess drainage and severe ENSO events. Examples are given for a number of peat swamp forest areas in Sumatra and Borneo. 3.Peat swamp hydrology is studied along a 23-km transect, which crosses a complete peat dome. First results show the relevance of surface runoff and peat soil roughness in the description of flooding events, and have been used to produce an improved hydrological description. 4.Since the dynamics of flooding events can potentially be observed by the ALOS PALSAR instrument (yet to be launched), this new hydrological model can be used to infer parameters relevant for detection of ecosystem disturbance and evaluation of restoration efforts. Copyright © 2007 John Wiley & Sons, Ltd. [source] High mountains of the Japanese archipelago as refugia for arctic,alpine plants: phylogeography of Loiseleuria procumbens (L.) Desvaux (Ericaceae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009HAJIME IKEDA According to previous phylogeographic studies, high mountains at low latitudes are important areas for the study of the evolutionary history of arctic,alpine plants in surviving the Pleistocene climatic oscillations. To evaluate this hypothesis, we elucidated the genetic structure of the arctic,alpine plant, Loiseleuria procumbens, in the Japanese archipelago, which corresponds to one of the southernmost limits of its distribution, using 152 individuals from 17 populations that covered the entire distribution of the Japanese archipelago and Sakhalin, in addition to samples from Sweden. Based on 854 bp of chloroplast DNA, we detected eight haplotypes. Along with haplotype distribution, strong genetic differentiation between populations in central and northern Japan was elucidated by a neighbour-joining tree (100%) and spatial analysis of molecular variance (79%), which is consistent with other alpine plants in Japan, regardless of the species' range. In addition, the southernmost populations from northern Japan showed specific genetic structure, although the remaining areas of northern Japan and Sakhalin harboured an homogenous genetic structure. Our results suggest that the populations in central Japan persisted for a long time during the Pleistocene climatic oscillation and that genetic divergence occurred in situ, supporting our hypothesis in conjunction with a previous study of another arctic,alpine plant, Diapensia lapponica subsp. obovata. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 403,412. [source] Forest Conversion and Degradation in Papua New Guinea 1972,2002BIOTROPICA, Issue 3 2009Phil L. Shearman ABSTRACT Quantifying forest change in the tropics is important because of the role these forests play in the conservation of biodiversity and the global carbon cycle. One of the world's largest remaining areas of tropical forest is located in Papua New Guinea. Here we show that change in its extent and condition has occurred to a greater extent than previously recorded. We assessed deforestation and forest degradation in Papua New Guinea by comparing a land-cover map from 1972 with a land-cover map created from nationwide high-resolution satellite imagery recorded since 2002. In 2002 there were 28,251,967 ha of tropical rain forest. Between 1972 and 2002, a net 15 percent of Papua New Guinea's tropical forests were cleared and 8.8 percent were degraded through logging. The drivers of forest change have been concentrated within the accessible forest estate where a net 36 percent were degraded or deforested through both forestry and nonforestry processes. Since 1972, 13 percent of upper montane forests have also been lost. We estimate that over the period 1990,2002, overall rates of change generally increased and varied between 0.8 and 1.8 percent/yr, while rates in commercially accessible forest have been far higher,having varied between 1.1 and 3.4 percent/yr. These rates are far higher than those reported by the FAO over the same period. We conclude that rapid and substantial forest change has occurred in Papua New Guinea, with the major drivers being logging in the lowland forests and subsistence agriculture throughout the country with comparatively minor contributions from forest fires, plantation establishment, and mining. RESUMEN Sopos long kisim gutpela save long senis i kamak long tropics em i wanpela bik pela samting long wanem, bikpela bus em wanpela hap we wok konsevason na carbon cycle bai inap kirapim gutpela wok. Insait long olgeta hap long world, PNG em wanpela hap we bikpela bus em i stap yet. Insait long dispela wok mipela soim olsem bikpela senis em i kamap long insait long bikpela bus na long hamas bikpela bus yumi gat. Nogat wanpela kain wok painimaut emi painim dispela senis bipo. Mipela lukluk gut long we olgeta bikpela bus i raus na we bus i kisim bagarap insait long, yia 1972 i kamap inap long yia 2002. Long yia 1972 mipela i usim map ol i kolim land cover map na long yia 2002 mipela lukluk long olgeta PNG high-resolution satellite imagery. Long yia 2002, 28,251,967 hectares bikpela bus i stap insait long Papua New Guinea. Long namel long 1972 igo inap long 2002, Papua New Guinea i lusim 15 percent long algeta bipela bus belong en. Insait long dispela 15 percent, 8.8 percent em i kamap bikos ol lain i katim diwai long salim. As bilong senisim bikela bus emi stap long ples we igat bikpela diwai long katim. Insait long dispela hap yumi lusim 36 percent, sampela we yumi inap long salim, tasol narapela emi bikos yumi rausim bus long wokim gaden or narapela kainkain pasin yumi wokim. Long 1972 i kamap inap long yia 2002, yumi lusim 13 percent long bikpela bus raonim ol bikpela maunten. Mipela painim olsem, long yia 1990 igo inap long yia 2002, long algeta kantri kain senis i wok long kamap bikpla. Senis istap insait long 0.8 igo inap long 1.8 percent long wan wan yia, tasol insait long wan wan liklik hap some pela i kisim bikpela senis, na ol narapela ino tumas. Long ol hap igat gutpela diwai long katim, senis i stat long 1.1 percent igo inap 3.4 percent. Dispela senis em i winim estimates we ol lain FAO i bin tokaut long em bipo. Long dispela wok painimaut, mipela iken tok olsem, as bilong dispela bikpela senis emi kamap long wanem ol i rausim na bagarapim bikpela bus. Dispela asua i kamap taim yumi rausim planti diwai tumas long salim na sampela taim yumi katim bus long wokim garden. Sampela taim bikpela paia tu i save kukim bikpela bus. [source] Dermoscopic pattern of intermediate stage in seborrhoeic keratosis regressing to lichenoid keratosis: report of 24 casesBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2007P. Zaballos Summary Background, Lichenoid keratosis (LK) is a well-described entity which has been proposed to represent an immunological or regressive response to pre-existing epidermal lesions such as solar lentigines or seborrhoeic keratoses. Objectives, To evaluate the dermoscopic criteria of a series of cases of LK with remaining areas of seborrhoeic keratosis which were both dermoscopically and histologically diagnosed. Methods, Pigmented lesions with dermoscopic areas of seborrhoeic keratosis and LK in the same tumour were consecutively diagnosed and prospectively included in the study. All pigmented lesions were examined and registered using DermLite Foto equipment (3Gen, LLC, Dana Point, CA, U.S.A.), at 10-fold magnification, at the Dermatology Department of Hospital de Sant Pau i Santa Tecla (Tarragona, Spain), between 1 January 2003 and 31 December 2005. Results, In total, 24 cases of lesions with dermoscopic areas of seborrhoeic keratosis and LK were collected. In four lesions (17%), the clinical differential diagnosis without dermoscopy included malignant melanoma and in seven lesions (29%), basal cell carcinoma. The diagnosis of LK was clinically considered without dermoscopy in only six cases (25%). A granular pattern was observed to be distributed throughout the LK areas of the lesions. This pattern consisted of the presence of brownish-grey, bluish-grey or whitish-grey coarse granules that formed, in 11 cases (46%), globules and/or short lines. In one lesion, located on the face, these short lines produced annular or rhomboid structures as seen in lentigo maligna melanoma. Conclusions, Dermoscopy is a useful tool which assists in the correct clinical recognition of LK, which may also potentially illuminate the pathogenesis of these tumours, showing the intermediate stage of regressing epidermal lesions in an LK. [source] | ||||||||||||||||