Miracle-dz/UniFAR-FTUs huggingface dataset:
Sustainable Land-based Aquaculture: Rational Utilization of Water, Land and Feed Resources

Much has been said on the need to practice aquaculture in a sustainable manner, preferably without jeopardizing the environment (Naylor, et al. 2000 and FAO 1997). As a result, best management practices for the aquaculture industry, considering environmental, economic and social sustainability, have been established (e.g. www.gaalliance.org/bap.html). Standards of some organizations for organic farming restrict stocking density and maximum pond biomass per unit surface area. For example, to produce organic shrimps, less than 15 postlarvae (PL) per square meter should be stocked with shrimp biomass always remaining below 800kg/ha (e.g. Naturland standards 2004; www.naturland.de/ englisch/n2/NL-Stand-Aquaculture_01-2005. pdf). These rules were mainly put forward to protect shrimp health and welfare, and to avoid the development of diseases. Naylor et al. (2000) stated that “intensification implies increasing the density of individuals, which requires greater use and management of inputs and greater generation of waste products”. Such rules or statements suggest that intensification will always lead to the production of more wastes or to a reduction of animal welfare, which should be avoided.
Thermal cracks in floating ice sheets

When the air temperature drops below the water temperature under a floating ice sheet, thermal cracks often occur. To acquire quantitative information on these cracks from an analytic point of view, the ice has been represented as a homogeneous elastic floating plate. The effect of thermal contraction then becomes equivalent to a lateral surface load. After the problem has been formulated in general terms, three special conditions which lend themselves to analytic treatment are considered: the wide ice sheet under conditions of plane strain, the narrow ice sheet under plane stress conditions and the axisymmetric ice sheet. The first two lead to simple solutions that illustrate general effects, the third is of more practical significance. Typical stress distributions prior to cracking are shown and for particular numerical values, some of which are applicable to arctic sea ice; typical crack spacing is related to the temperature difference between the upper and lower surface. Finally, the assumptions on which the analysis rests are examined critically with regard to establishing the validity of the results and to indicate ways in which improvements in the analytic treatment can be made.
A Numerical Simulation of Sea Ice Cover in Hudson Bay

Abstract Hibler's dynamic-thermodynamic sea ice model with viscous-plastic rheology is used to simulate the seasonal cycle of sea ice motion, thickness, compactness, and growth rate in Hudson Bay under monthly climatological atmospheric forcing and a prescribed ocean surface current field. The sea ice motion over most of the domain is driven mainly by the wind stress. Wintertime sea ice velocities are only of the order of 1–5 (× 10−4 m s−1) due to the nearly solid ice cover and the closed boundary constraint of Hudson Bay. However, the velocities rise to 0.10–0.20 m s−1 during the melting and freezing seasons when there is partial ice cover. The simulated thickness distribution in mid–April, the time of heaviest ice cover, ranges from 1.3 m in James Bay to 1.7 m in the northern part of Hudson Bay, which compares favorably with observations. The area-averaged growth rate, computed from the model is 1.5–0.5 cm day−1 from December to March, is negative in May (indicative of melting) and reaches its minimum v.
Seismic evidence for large‐scale compositional heterogeneity of oceanic core complexes

Long‐lived detachment faults at mid‐ocean ridges exhume deep‐seated rocks to form oceanic core complexes (OCCs). Using large‐offset (6 km) multichannel seismic data, we have derived two‐dimensional seismic tomography models for three of the best developed OCCs on the Mid‐Atlantic Ridge. Our results show that large lateral variations in P wave velocity occur within the upper ∼0.5–1.7 km of the lithosphere. We observe good correlations between velocity structure and lithology as documented by in situ geological samples and seafloor morphology, and we use these correlations to show that gabbros are heterogeneously distributed as large (tens to >100 km2) bodies within serpentinized peridotites. Neither the gabbros nor the serpentinites show any systematic distribution with respect to along‐isochron position within the enclosing spreading segment, indicating that melt extraction from the mantle is not necessarily focused at segment centers, as has been commonly inferred. In the spreading direction, gabbros are consistently present toward the terminations of the detachment faults. This suggests enhanced magmatism during the late stage of OCC formation due either to natural variability in the magmatic cycle or to decompression melting during footwall exhumation. Heat introduced into the rift valley by flow and crystallization of this melt could weaken the axial lithosphere and result in formation of new faults, and it therefore may explain eventual abandonment of detachments that form OCCs. Detailed seismic studies of the kind described here, when constrained by seafloor morphology and geological samples, can distinguish between major lithological units such as volcanics, gabbros, and serpentinized peridotites at lateral scales of a few kilometers. Thus such studies have tremendous potential to elucidate the internal structure of the shallow lithosphere and to help us understand the tectonic and magmatic processes by which they were emplaced.
La diversidad del zoobentos en ríos de montaña del noroeste de Argentina: comparación entre seis ríos

Zoobenthic diversity in mountain rivers of northwestern Argentina: a comparison among six rivers: The structure of the benthic community of six rivers belonging to three subtropical basins from northwestern Argentina is analyzed. All the sampling stations were located in the mountain rain forest (Yungas) ecoregion. Seventy-eight taxa were recorded, although with a great difference in the total individual density among the considered rivers. Based on their taxonomic similarity (50%), three stations grouped together: Medina, Yala and Candelaria rivers (with more than 35 taxa), while the remaining rivers (Pueblo Viejo, Piedras and Conchas) formed a second group (with 27 taxa or fewer). According to rarefaction analysis of subsamples of 250 individuals, species richness clearly separates Yala and Conchas rivers from the others. According to the Correspondence Analysis, stations were ordered following the gradients of magnitude and altitude of the rivers. The groups formed by taxonomic similarity, rarefaction and Correspondence Analysis were due more to local peculiarities rather than to basin characteristics. Ecología Austral 11:916. Junio 2001 Asociación Argentina de Ecología * Fundación Miguel Lillo; Miguel Lillo 251; 4000, San Miguel de Tucumán, ARGENTINA. fatiromero@yahoo.com. ar Recibido: 9 octubre 2000; Aceptado: 14 marzo 2001 INTRODUCCIÓN Es ampliamente aceptado que en la región Neotropical hay un mayor conocimiento de los grandes ríos que de los pequeños (Covich 1988). En Argentina solo recientemente se han iniciado estudios detallados sobre el bentos de ríos de distintas regiones (Corigliano & Cosarini 1984; Wais & Bonetto 1988; Marchese & Drago 1992; Corigliano & Freytes 1994; Miserendino 1995; Peso 1995). En la extensa y heterogénea área que corresponde a la subregión de las Sierras en el noroeste argentino (Bianchi & Yañez 1992), se extienden las selvas subtropicales de montaña. Estas selvas, conocidas como Yungas (Figura 1), están constituidas por tres pisos de vegetación con un claro gradiente de riqueza nortesur, que son cruzados por numerosos ríos que nacen en las serranías del oeste (Morales 1996). En la provincia de Tucumán, algunos de estos ríos presentan una alta diversidad de macroinvertebrados (Fernández & Palacios 1989; Fernández et al. 1995; Romero & Fernández 2001); sin embargo, la estructura de la comunidad bentónica y los factores que la determinan son desconocidos. Los factores físicos ejercen su influencia sobre los macroinvertebrados de los ríos según una jerarquía de escalas espaciales en la que 10 HR FERNÁNDEZ ET AL. Ecología Austral 11:916
Buoyancy‐driven deformation and contemporary tectonic stress in the lithosphere beneath Central Italy

We studied the continental deformation and modelled the contemporary flow and stress distribution in the lithosphere beneath Central Italy. We made use of a revisited crust and uppermost mantle Earth structure that supports delamination processes. The model behaviour is primarily determined by the thick high density lithospheric root to the east and the low‐viscosity shallow mantle wedge to the west. The rate of the modeled crustal motion is in agreement with GPS data and the pattern of lithospheric flow explains the heat flux, the regional geology and provides a new background for the genesis and age of the recent Tuscan magmatism. The modelled stress in the lithosphere is spatially correlated with the prevailing stress field and the gravitational potential energy patterns and shows that buoyancy forces, solely, can explain the coexisting regional contraction and extension and the unusual sub‐crustal seismicity.
Cavitation and Size Scale Effects for Orifices

Cavitation data are presented for circular sharp-edged orifices which identify incipient, critical, moderate, heavy, and choking cavitation. The experimental program included pipe sizes from 1 to 23.5 in. (25 to 597 mm), pressures from 20 to 200 psi (140 to 1,400 kn/m²), and orifice size ratios from β = 0.332 to 0.884. Incipient and critical cavitation are affected by pipe size but are independent of pressure and velocity. Choking cavitation is independent of pressure, velocity, and size. An accelerometer was used to evaluate incipient and critical limits. Moderate and heavy cavitation regions were selected by aural observations. Choking flow was identified as the flow condition where the discharge coefficient began to rapidly decrease.
Crops and environmental change : an introduction to effects of global warming, increasing atmospheric CO[2] and O[3] concentrations, and soil salinization on crop physiology and yield

* Preface and Acknowledgments * Abbreviations * Chapter 1. Introduction * Human Population Growth * Environmental Changes * Crops and Food Supply * Population, Crop Yield, and Crop Production * Summary * Chapter 2. Methods of Studying Effects of Environmental Change on Crops * Correlations Between Observed Yield and Historical Patterns of Environmental Variation and Change * Experimental Control of Environmental Conditions * Methods for Salinity Studies * Summary * Chapter 3. Cellular Responses to the Environment * Membrane Structure and Function * Enzymes * Cellular Mechanisms of Stress Resistance * The Role of Calcium in Stress Responses * Specificity, Cross-Talk, and Cross-Tolerance * Summary * Chapter 4. Water Relations * The Future of Fresh Water Resources * Effects of Climate Change on Global Hydrology * Excess Precipitation * Drought * Water Uptake, Transport in Xylem, and Transpiration * The Plant Surface * Roots and Hydraulic Conductance * The Crop Canopy * Environmental Changes * Summary * Chapter 5. Photosynthesis, Respiration, and Biosynthesis * Photosynthesis * Effects of Environmental Conditions and Changes on Photosynthesis * Respiration * Effects of Environmental Conditions and Changes on Respiration * Biosynthesis * Summary * Chapter 6. Partitioning of Photosynthate * Source and Sink * Harvest Index * Methods for Studying Partitioning * Carbon Partitioning Within Source Leaves * Phloem Loading, Transport, and Unloading * Regulation of Whole Plant Carbon Partitioning * Environmental Changes * Summary * Chapter 7. Mineral Nutrition * Nutrient Passage from Soil to Root and Beyond * Regulation of Ion Uptake * Kinetics of Nutrient Uptake * Environmental Changes * Summary * Chapter 8. Vegetative Growth and Development * Growth Patterns * Meristems, Organs, and Development * Shoots * Roots * Developmental Stages * Environmental Changes * Summary * Chapter 9. Sexual Reproduction, Grain Yield, and Grain Quality * Sexually Reproductive Development * Yield Components and Variation * Environmental Changes * Interactive Effects of Environmental Changes on Yield * Summary * Chapter 10. The Biotic Environment * Weeds * Insect Pests and Diseases * Symbiotic Relationships with Soil Organisms * Multiple Environmental Changes and Implications for Biotic Interactions * Summary * Appendix A: List of Plant Species * Appendix B: Definition of U.S. "Principal Crops" * References * Index
Radium, thorium and radioactive lead isotopes in groundwaters: application to the in situ determination of adsorption-desorption rate constants and retardation factors

Five groundwater samples taken from different Hydrogeologie settings in Connecticut were analyzed for major cation chemistry and the concentration of U and Th decay series nuclides 238U, 234Th, 226Ra, 222Rn, 210Pb, 210Po, 232Th, 228Ra, 228Th, and 224Ra. The concentration of 222Rn in the waters ranged between 103 and 104 dpm l−1 and was three to four orders of magnitude greater than that of the short-lived alpha daughters 224Ra, 228Ra, and 234Th, even though the rates of supply of these four nuclides to solution are expected to be similar. We infer that sorption removes radium and thorium from these groundwaters on a time scale of 3 minutes or less. The (224Ra/228Ra) and (234Th/228Th) activity ratios in these waters indicate that desorption of these nuclides occurs on a time scale of a week or less and that equilibrium between solution and surface phases is established. In situ retardation factors for radium, thorium, and lead may therefore be calculated directly from the isotopic data; values range from 4,500 to 200,000. Neither sorption time scales nor retardation factors are strongly dependent on the nuclide or on hydrogeology of the aquifer. Since our study includes nuclides with diverse chemical properties, we suggest that other uncomplexed heavy metals and transuranic elements will also behave in a manner similar to those measured here. The approach presented here should therefore find application in developing site-specific models of the transport of radioactive or stable elemental waste through water-saturated media.
QUALIDADE DA ÁGUA EM UMA MICROBACIA DE USO AGRÍCOLA E URBANO EM XANXERÊ – SC.

As atividades humanas que acontecem sobre uma bacia hidrografica influenciam aspectos da qualidade das aguas e pode restringir os possiveis usos do recurso hidrico. Diante disso, foi realizado um trabalho de avaliacao da qualidade da agua do rio Ditinho, localizado em Xanxere - SC, e que serve de manancial de abastecimento para a populacao deste municipio. Preliminarmente, uma caracterizacao da microbacia foi feita mediante um levantamento das atividades desenvolvidas na area urbana e rural. A avaliacao da qualidade da agua foi realizada durante oito meses atraves de coletas de amostras em quatro diferentes estacoes distribuidas ao longo do rio. Os resultados mostraram que a ocupacao e o uso do solo na microbacia sao predominantemente voltados as atividades agropecuarias. Algumas amostras de agua do rio Ditinho apresentaram desconformidade em relacao a legislacao para rios de classe 2 (Conama, 2005), referentes a contaminacao por coliformes termotolerantes (> 1100 UFC/100 mL), nitrogenio amoniacal (6,6 mg/L), turbidez (177 UNT) e pH (5,7). Essas alteracoes registradas na qualidade da agua do rio, em especial na area de nascente, estao associadas ao manejo inadequado de dejetos animais e a intensa ocupacao e uso do solo para a agricultura na microbacia. Palavras-chave : atividades agropecuarias; qualidade da agua; rio Ditinho; abastecimento publico ABSTRACT Water quality in a watershed used for agricultural and urban purposes in Xanxere – Santa Catarina State, Brazil. Anthropomorphic activities that happen on a watershed influence the water quality aspects and may restrict the possible use of hydric resources. Thus, an evaluation of the quality of the water of the Ditinho River in Xanxere – Santa Catarina State, Brazil, was carried out. This river serves as fountainhead for the population of this town. Preliminarily, a characterization of the watershed was carried out through a survey of the activities developed in the urban and rural areas. The water quality evaluation was performed during eight months through samplings at four stations distributed along the river. The results show that the occupation and the use of the soil on the watershed are predominantly turned to farming and cattle raising activities. Some water samples from the Ditinho River were not in agreement with the legislation regarding rivers of class 2 (Conama, 2005) and they showed contamination by thermotolerant coliforms (> 1100 UFC / 100 mL), ammoniacal nitrogen (6.58 mg/L), turbidity (177 UNT), and pH (5.7). Such changes registered in the quality of the river, in special at the source area, are associated to improper management of the animal excrements and the intense occupation and use of the soil for agriculture on the watershed. Keywords: farming and cattle raising activities, water quality, Ditinho river, public supply
Factors Controlling Soil Carbon Levels in New Zealand Grasslands Is Clay Content Important

Soil organic matter is a major component of biogeochemical cycles and is important in maintaining soil quality. We investigated relationships between soil organic C and various soil and site properties that may influence long-term soil C accumulation across a range of soil orders in New Zealand. We used pedon and climatic data for 167 pedons under permanent grass, and carried out regression analysis between soil C (0-200 mm) contents it ha -1 ) or concentrations (g kg -1 ) and climatic and soil properties, namely, precipitation, temperature, and contents or concentrations of sand, silt, clay, pyrophosphate-extractable Al (Al py ), Fe oxide, and allophane. Soil clay content or concentration explained little of the variation in soil C across all soils (R 2 < 0.05) and within each soil type. Likewise, mean annual precipitation and temperature explained little variation in soil C content or concentration (R 2 < 0.15 for precipitation, R 2 = 0.04 for temperature). Allophane content or concentration was unrelated to soil C in the soils of volcanic origin; Al py , however, correlated strongly with both soil C content and soil C concentration across all soil types (R 2 = 0.55 and 0.60, respectively). When all factors were combined in a multiple regression analysis, the combination of Al py and allophane contents explained the greatest amount of variation in soil C content (R 2 = 0.57), whereas the combination of Al py , Fe oxide, allophane, and clay concentrations explained the greatest amount of variation in soil C concentration (R 2 = 0.67). Out results suggest that in New Zealand soils, chemical stabilization of organic matter is the key process controlling soil C accumulation, and that clay content relates poorly to long-term soil organic C accumulation.
Piper Oil Field

Piper oil field lies in UK block 15/17, near the eastern end of the Moray Firth basin, 125 mi (200 km) northeast of Aberdeen, Scotland. The field was discovered in January, 1973 and confirmed as a major oil field in 1973 with five appraisal wells and one exploratory well. A steel platform with 36 well slots and space for two drilling rigs was centrally located over the field in 474 ft (144 m) of water in June, 1975, and made ready for production drilling by October 1976. Production is from the Upper Jurassic Piper Sandstone, a high energy, marginal marine and shallow-marine, shelf sandstone with gross thickness ranging from 160 to 465 ft (50 to 142 m); net sand ranges from 131 to 378 ft (40 to 115 m); average porosity is 24%; permeabilities range from 200 to 1,200 md in lower energy bioturbated sandstones, and range from 2,000 to 10,000 md in higher energy sandstones. Kimmeridge Shale is the caprock over most of the field, but Upper Cretaceous marlstones provide the seal along some fault scarps where the Kimmeridge was removed during the Cenomanian. The field is comprised of three folded, tilted blocks on the northern edge of the Witch Ground graben. Block I, a gently folded fault block dipping 5° northeast, has a common oil-water contact of 8,512 ft (2,594 m) subsea with Block II. Block II, a downthrown, northwest to southeast trending fault block lies southwest of Block I. Blocks I and II cover 7,149 productive acres (2,894 ha.) and have a gross reservoir column of 1,312 ft (399 m), from 7,200 ft (2,195 m) subsea to the oil-water contact. Block III (to the southwest) borders the Witch Ground graben and contains a small accumulation with a separate oil-water contact at 9,199 ft (2,804 m) subsea. The P1 production well spudded October 10, 1976, established commercial production December 7, 1976, at more than 30,000 b/d, restricted by 5 1/2 in. (14 cm) tubing. The P7 well completed in April 1977 produced more than 50,000 b/d, restricted by 7 in. (17.8 cm) tubing. Twenty-five wells have been drilled, four as water injectors to support a natural water drive of 250,000 b/d. Production is 280,000 ± b/d of 37° API, low sulfur oil and original recoverable reserves are estimated to be 618 million bbl. Piper sand stratigraphy, reservoir performance, and development from a centrally located platform are discussed in detail.
Recent Climate‐Induced Changes in Freshwaters in Denmark

Erik Jeppesen1,2,3, Brian Kronvang1, Torben B. Jorgensen1,4, Soren E. Larsen1, Hans E. Andersen1, Martin Sondergaard1, Lone Liboriussen1, Rikke Bjerring1, Liselotte S. Johansson1, Dennis Trolle1, and Torben L. Lauridsen1,2 1Department of Bioscience, Aarhus University, Denmark 2Sino-Danish Centre for Education and Research (SDC), Beijing, China 3Greenland Climate Research Centre (GCRC), Greenland Institute of Natural Resources, Nuuk, Greenland 4Limfjordssekretariatet, Norresundby, Denmark
A study of the relationship between stratospheric gravity waves and polar mesospheric clouds at Davis Antarctica

[1] We used a Rayleigh lidar located at Davis station, East Antarctica, to compare Polar Mesospheric Cloud (PMC) and stratospheric gravity wave (GW) strengths in the austral summer 2005–2006. Earlier similar studies from Greenland noted that intervals of large stratospheric GW activity appeared to coincide with reduced PMC strengths. We measure the stratospheric GW strength in the 30–45 km altitude range, for waves of vertical wavelength between ∼2 and ∼10 km, and of periods greater than 1 h. We find little consistency with the Greenland studies, as the occurrence of PMC over Davis appear to have little relationship to observed stratospheric gravity wave activity. Hemispheric differences, in both PMC strength and occurrence and in gravity wave strength, may have a role in explaining our results. Our data suggest that a significant controller of occurrence of PMC over Davis is related to diurnal tidal movement. We also investigate the potential influence of sampling biases in our data set.