Application of Zoning and “Limits of Acceptable Change” to Manage Snorkelling Tourism

Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and “Limits of Acceptable Change” (LAC). As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable. The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives.     

The effect of five forage species on transport and transformation of atrazine and isoxaflutole (balance) in lysimeter leachate

A field lysimeter study with bare ground and five different ground covers was established to evaluate the effect of forage grasses on the fate and transport of two herbicides in leachate. The herbicides were atrazine (ATR; 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) and isoxaflutole [IXF; 5-cyclopropyl-4-(2-methylsulfonyl-4-trifluormethyl-benzoyl)isoxazole], which has the commercial name Balance (Aventis Crop Science, Strasbourg, France). The ground covers included orchardgrass (Dactylis glomerata L.), smooth bromegrass (Bromus inermis Leyss.), tall fescue (Festuca arundinacea Schreb.), timothy (Phleum pratense L.), and switchgrass (Panicum virgatum L.). The results suggested that the total IXF (parent + metabolites) showed higher mobility than ATR and its metabolites. Differences in the timing of transport reflected the rapid degradation of IXF to the more soluble, stable, and biologically active diketonitrile (DKN) metabolite in the system. Although grass treatments did not promote the hydrolysis of DKN, they significantly reduced its transport in the leachate through enhanced evapotranspiration. Grass treatments significantly enhanced ATR degradation in the leachates and soils, especially through N dealkylation, but they did not reduce total ATR transported in the leachate. Leachate from the orchardgrass lysimeters contained the highest proportion of ATR metabolites (64.2%). Timothy and smooth bromegrass treatments also displayed a significant increase in ATR metabolites in leachate. Grass-treated lysimeters showed higher microbial biomass carbon than bare ground. For ATR treatments, the proportion of metabolites in the leachate strongly correlated with the elevated soil microbial biomass carbon in forage treatments. In contrast, DKN degradation was poorly correlated with soil microbial biomass carbon, suggesting that DKN degradation is an abiotic process.     

A concept for simultaneous wasteland reclamation, fuel production, and socio-economic development in degraded areas in India: Need, potential and perspectives of Jatropha plantations

The concept of substituting bio‐diesel produced from plantations on eroded soils for conventional diesel fuel has gained wide‐spread attention in India. In recent months, the Indian central Government as well as some state governments have expressed their support for bringing marginal lands, which cannot be used for food production, under cultivation for this purpose. Jatropha curcas is a well established plant in India. It produces oil‐rich seeds, is known to thrive on eroded lands, and to require only limited amounts of water, nutrients and capital inputs. This plant offers the option both to cultivate wastelands and to produce vegetable oil suitable for conversion to bio‐diesel. More versatile than hydrogen and new propulsion systems such as fuel cell technology, bio‐diesel can be used in today's vehicle fleets worldwide and may also offer a viable path to sustainable transportation, i.e., lower greenhouse gas emissions and enhanced mobility, even in remote areas. Mitigation of global warming and the creation of new regional employment opportunities can be important cornerstones of any forward looking transportation system for emerging economies.     

Comparison of criteria for prediction of runaway reactions in the sulphuric acid catalyzed esterification of acetic anhydride and methanol

Loss of temperature control is one of the major reasons that can lead to runaway reaction. This occurrence is commonly named thermal runway. The aim of this paper is the application of thermal runaway criteria in order to predict the onset of runaway phenomena and define the range of stability related to operating conditions in the reactor, with specific reference to the esterification of acetic anhydride and methanol catalysed by sulphuric acid tested in isoperibolic conditions. The isoperibolic calorimeter has also been used to obtain thermodynamic, kinetic and physical chemistry data necessary to develop a model for the reaction. Some runaway criteria applied in this work require a model for the process, so a model for the analyzed system been developed.Because of the modest reaction enthalpy and low activation energy this reacting system provide a severe test to the runaway criteria.In this work, various runaway criteria have been applied to the experimental and simulated data and the results obtained have been compared.     

Phytoremediation of a Petroleum‐Hydrocarbon Contaminated Shallow Aquifer in Elizabeth City,North Carolina,USA

A former bulk fuel terminal in North Carolina is a groundwater phytoremediation demonstration site where 3,250 hybrid poplars, willows, and pine trees were planted from 2006 to 2008 over approximately 579,000 L of residual gasoline, diesel, and jet fuel. Since 2011, the groundwater altitude is lower in the area with trees than outside the planted area. Soil‐gas analyses showed a 95 percent mass loss for total petroleum hydrocarbons (TPH) and a 99 percent mass loss for benzene, toluene, ethylbenzene, and xylenes (BTEX). BTEX and methyl tert‐butyl ether concentrations have decreased in groundwater. Interpolations of free‐phase, fuel product gauging data show reduced thicknesses across the site and pooling of fuel product where poplar biomass is greatest. Isolated clusters of tree mortalities have persisted in areas with high TPH and BTEX mass. Toxicity assays showed impaired water use for willows and poplars exposed to the site's fuel product, but Populus survival was higher than the willows or pines on‐site, even in a noncontaminated control area. All four Populus clones survived well at the site. © 2014 Wiley Periodicals, Inc.*     

PLANNING FOR THE REHABILITATION OF GRAVEL PITS1

ABSTRACT: By field investigations and planning, it is profitable to rehabilitate gravel pits as recreational lakes in urban areas. Some of the important aspects to be considered are topography, soil, surface water and groundwater. A case study is presented and some general guidelines in the rehabilitation process are given. This kind of a use for derelict land is important at the present time as there is a growing demand for recreational lakes in urban areas.     

ADAPTATION TO ARIDITY: WATER DEVELOPMENT IN SOUTH AFRICA1

ABSTRACT The Republic of South Africa, legatee of a three-century history of recurring drought, is firmly committed to a program of the optimum use of its water for the national benefit. Its water law encourages centralized planning in that water is held to be the property of the state and is assignable without requiring acquiescence by the basin or province of origin. Interbasin diversions from the Tugela River to the Vaal River Basin, from the Orange River to the Fish and Sundays River Basins, and from several basins to Cape Town are under construction as are facilities for water importation from Lesotho and Angola. For satisfaction of demands beyond the year 2000 the nation may depend increasingly on a shift of its power production and water-using industry from the coal fields of the central plateau to nuclear power development with associated desalination along its coasts. Alternatively, and preferably, it may cooperate in a co-prosperity bloc in Southern Africa aiding the economies of its neighbors by development for mutual advantage of the water and power resources of the Okavango and other northern rivers.