New morpho-bathymetric data on marine hazard in the offshore of Gulf of Naples (Southern Italy)

Natural Hazards - Morpho-bathymetric data have been analyzed in order to provide new geological evidence on the Gulf of Naples, i.e., on the southern Ischia slope, on the Naples canyons and on the...     

Rural tourism in Spain: an analysis of recent evolution

The aim of this paper is to analyse the evolution of Rural Tourism¹ (RT) in Spain within a European context. The first step is to examine the development of different “models” of RT and trace some experiences of the application of European policy. In order to set the scene and understand this evolution, the collective imagery on which RT is based is also analysed. This is followed by a study of the development of tourist products and services in rural Spain since the 1980s, as diversification of the traditional sun/sand/sea (3S) tourist economy is sought. The analysis underlines the importance of the role of women, and the consequences of the activity for the economy of rural areas. The purpose is to identify differences in the pattern of evolution with more northern European countries, understand their causes and formulate recommendations for future development.     

Effects of 17beta-estradiol exposure in the mussel Mytilus galloprovincialis

Mussels Mytilus galloprovincialis were exposed to different concentrations of estradiol (20, 200, and 2000 ng/l) in a semi-static regime (1-day dosing intervals) for up to 7 days in an attempt to see how mussels dealt with exogenous estrogenic compounds. Sex hormone levels were determined in whole tissue. Free-estradiol was only significantly elevated at the highest exposure dose (up to 10-fold). Most of the estradiol was in the tissues as fatty acid esters (> 78%), which sharply increased in a dose-dependent manner (from 4 ng/g in controls to 258 ng/g at the high exposure group). In contrast, neither free nor esterified testosterone levels showed significant differences between control and exposure groups. The results suggest the existence of mechanisms that allow mussels to maintain their hormonal status, and the important role that fatty acid esterification may play within those mechanisms. Synthesis and conjugation rates of estradiol were further investigated by measuring the activity of P450 aromatase, and palmitoyl-CoA:estradiol acyltransferase, in digestive gland microsomal fractions. Overall, the study contributes to the better knowledge of molluscan endocrinology, and defines new mechanisms of regulation of free steroid-levels in mussels.     

Geology and volcanic stratigraphy of the Canatuan and Malusok volcanogenic massive sulfide deposits,southwestern Mindanao,Philippines

The Canatuan and Malusok massive sulfide deposits are located near Siocon, Zamboanga del Norte, in southwestern Mindanao, Philippines. The Canatuan–Malusok area is underlain by the Jurassic–Cretaceous Tungauan schists, which form much of the Zamboanga Peninsula. The volcanic strata at Canatuan and Malusok can be traced for >7 km along strike and is host to at least three discrete massive sulfide bodies: Canatuan, Malusok and SE Malusok. Basal basaltic andesite volcanic rocks are generally chemically uniform and show only moderate alteration. The massive sulfide deposits occur in overlying rhyolitic to rhyodacitic volcanic rocks that are altered to a schistose assemblage of quartz, sericite, chlorite and pyrite. The alteration is texturally destructive but graded clastic beds are locally observed. Despite tropical saprolitic weathering, four lithogeochemical subunits of the felsic package are identified. Stratigraphic interleaving, however, has made correlation of these units over any significant distance difficult. The sulfide lenses are overlain by a few metres of felsic schists which locally contain manganese-bearing silicates and oxides that serve as a stratigraphic marker. Hangingwall andesitic volcaniclastic rocks are discontinuously preserved, although where present, they consist of regularly bedded mafic volcanic sandstones. The lateral continuity of a manganese-bearing marker and flanking felsic volcaniclastic intervals indicate that locally the volcanic strata form a homoclinal sequence. The Canatuan Au–Ag–Cu–Zn deposit consists of a gossan overlying a massive sulfide lens. The sulfides and gossan are flat lying and hosted within felsic volcanic rocks. The gossan is gold–silver-rich, and was formed by a combination of oxidation and volume collapse of the original sulfide lens. The sulfide minerals present below the current water table, are auriferous massive pyrite with base metal sulfides, with some supergene chalcocite. The transition from gossan to sulfides is very sharp, occurring at the water table. Massive sulfide deposits at Malusok are hosted in the same felsic sequence as Canatuan and they have similar base and precious metal contents. Only limited gossan has been found at Malusok. The bimodal nature of the volcanic rocks at Canatuan, together with their low HFSE contents, near-flat REE patterns and tholeiitic affinities, suggest that they formed in an intra-oceanic arc setting above a depleted mantle source. Mafic and felsic volcanic rocks of similar composition have been recovered from the Tonga-Kermadec and Izu-Bonin-Marianas island-arc systems in the western Pacific. Mafic rocks at Canatuan show no evidence for LILE enrichment that characterizes melts derived from metasomatized mantle under more mature arcs, suggesting that they are the product of a nascent, rather than a mature arc. There is no evidence from the REE, or other incompatible trace elements, that continental crust or evolved arc crust was involved in the generation of the Canatuan-Malusok volcanic rocks. Although it has been proposed that the Zamboanga metamorphic complex comprises microcontinental fragments of Eurasian affinity, our data do not support an evolved crustal setting for the Canatuan-Malusok volcanic rocks, which we suggest were derived from an intra-oceanic arc and subsequently accreted to the eastern Mindanao terrane.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00126-003-0350-7Editorial handling: R.R. Large     

Morphology and sedimentary systems in the Central Bransfield Basin, Antarctic Peninsula: sedimentary dynamics from shelf to basin

A detailed regional characterization of the physiography, morphology and sedimentary systems of the Central Bransfield Basin (CBB) was carried out using swath bathymetry and high‐ and very high‐resolution seismic profiles. The basin margins show continental shelves with numerous glacial troughs, and continental slopes where relatively wide and flat slope platforms represent the middle domain in an atypical physiographic scenario in glaciated margins. Although the CBB is tectonically active, most of the morphologic features are sedimentary in origin, and can be classified into four sedimentary systems: (1) glacial‐glaciomarine, composed of erosional surfaces, glacial troughs, furrows and draping sheets; (2) slope‐basin, formed by trough mouth fans, slope aprons, the Gebra‐Magia instability complex and turbidity systems; (3) seabed fluid outflow system composed of pockmark fields; and (4) contourite, composed of drifts and moats. The sedimentary systems show a clear zonation from shelf to basin and their dynamics reflects the complex interplay among glacial, glaciomarine, marine and oceanographic processes involved in the entire shelf‐to‐basin sediment distribution. The CBB morphology is primarily controlled by glacial/interglacial cyclicity and physiography and to a lesser extent by tectonics and oceanography. These factors have affected the South Shetland Islands (SSI) and Antarctic Peninsula (AP) margins differently, creating a relatively starved SSI margin and a more constructional AP margin. They have also created two entire sediment‐dispersal domains: the shelf‐to‐slope, which records the glaciation history of the CBB; and the lower slope‐to‐basin, which records the imprint of local factors. This study provides a ‘source‐to‐sink’ sedimentary scheme for glaciated margins, which may be applied to the basin research in other margins, based on the characterization of sedimentary systems, their boundaries and the linkages among them. This approach proves to be adequate for the identification of global and local factors governing the CBB and may therefore be applied to other study areas.     

Rural poverty in Peninsular Malaysia and the Malaysian national agricultural policy

The National Agricultural Policy was implemented to arrest the decline that agriculture experienced in the 1970s and early 1980s. It aims to modernise and revitalise Malaysian agriculture and alleviate rural poverty while retaining labour in agriculture. This paper evaluates its likely effects on poverty among small‐scale padi farmers. The analysis is based on an evaluation of the strategies and programs that are being implemented as part of the policy. It is argued that the National Agricultural Policy will not alleviate poverty in the padi sub‐sector for three main reasons. Firstly, the strategies and programs currently being employed are essentially unchanged from those that were unsuccessfully employed in the past. Secondly, it is premised on a theoretical base which will not lead to the development of effective anti‐poverty strategies. And, finally, it is flawed by policy contradictions.     

Compositional variations of olivines and pyroxenes in chondritic interplanetary dust particles

Abstract We report here analyses of olivines and pyroxenes, and petrofabrics of 27 chondritic interplanetary dust particles (IDPs), comparing those from anhydrous and hydrous types. Approximately 40% of the hydrous particles contain diopside, a probable indicator of parent body thermal metamorphism, while this mineral is rarely present in the anhydrous particles. Based on this evidence, we find that hydrous and anhydrous IDPs are, in general, not directly related, and we conclude that olivine and pyroxene major-element compositions can be used to help discriminate between IDPs that are (1) predominantly nebular condensates, and lately resided in anhydrous or icy (no liquids) primitive parent bodies, and (2) those originating from more geochemically active parent bodies (probably hydrous and anhydrous asteroids).     

Preterrestrial aqueous alteration of the Lafayette (SNC) meteorite

Abstract— The Lafayette meteorite, a nakhlite of the SNC (Martian?) group, contains hydrous alteration materials as intergranular films and as veinlets and patches replacing olivine, pyroxenes, and high-Si glass. The alteration materials (“iddingsite”) consist of ferroan smectite clays, magnetite (or maghemite), and ferrihydrite, as shown by SEM and TEM. Three varieties of veinlets are present and formed in the order: coarse phyllosilicate; fine-grained (phyllosilicate-oxide), and porous oxide. Veinlets of fine-grained material cross-cut coarse phyllosilicate veinlets. The alteration materials are preterrestrial, as they are older than Lafayette's fusion crust, which is glassy and not affected by any alterations. Approaching the crust, the veinlets are progressively modified to the point of melting, and progressively depleted in adsorbed volatile constituents (S, Cl, and P). Bulk compositions of the alteration veinlets (SEM and TEM EDX) are consistent with the observed mineralogy, and suggest: that the smectite contains significant adsorbed S and Cl; that the ferrihydrite contains significant adsorbed S, but not Cl; that rare grains of sulfate (Ca?) and chloride (Na or K?) are present; and that the compositions of the alteration materials are approximated by Lafayette's olivine + high-Si glass + water. We estimate that Lafayette's alteration materials formed at less than 100 °C. The oxidation potential of the water was near or slightly below that of the magnetite-hematite buffer. The presence of sulfate and chloride in discrete phases and as adsorbates on ferrihydrite and smectite suggests that the altering solutions were saline. However, relatively little mass was transferred into or out of Lafayette because the bulk composition of the alteration materials is nearly isochemical with a mixture of magmatic silicate phases and water. Chemical transport within Lafayette was also limited, as alteration materials preserve some chemical signature of their host minerals. Presence of alteration materials along only some grain boundaries and some cracks suggests that Lafayette was not soaked in fluid. These last two inferences suggest that the alteration of Lafayette took place during episodic infiltrations of small volumes of saline water.     

Effects of 17β-estradiol exposure in the mussel Mytilus galloprovincialis

Mussels Mytilus galloprovincialis were exposed to different concentrations of estradiol (20, 200, and 2000 ng/l) in a semi-static regime (1-day dosing intervals) for up to 7 days in an attempt to see how mussels dealt with exogenous estrogenic compounds. Sex hormone levels were determined in whole tissue. Free-estradiol was only significantly elevated at the highest exposure dose (up to 10-fold). Most of the estradiol was in the tissues as fatty acid esters (>78%), which sharply increased in a dose-dependent manner (from 4 ng/g in controls to 258 ng/g at the high exposure group). In contrast, neither free nor esterified testosterone levels showed significant differences between control and exposure groups. The results suggest the existence of mechanisms that allow mussels to maintain their hormonal status, and the important role that fatty acid esterification may play within those mechanisms. Synthesis and conjugation rates of estradiol were further investigated by measuring the activity of P450 aromatase, and palmitoyl-CoA:estradiol acyltransferase, in digestive gland microsomal fractions. Overall, the study contributes to the better knowledge of molluscan endocrinology, and defines new mechanisms of regulation of free steroid-levels in mussels.     

Hurricane flood risk assessment for the Yucatan and Campeche State coastal area

Natural Hazards - In this study, the first ever Sea, Lake, Overland Surges from Hurricanes (SLOSH) grid was built for the Yucatan Peninsula. The SLOSH model was used to simulate storm surges in the...