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The impact of the use of natural resources associated with anthropogenic activities has increased evidently, mainly through land use changes which have altered hydrophysical properties of soils. We hypothesized that, in the same soil type (Vertisol), four types of land use system (grassland, agricultural, Eucalyptus plantation and thornscrub) and seasonal variation can modify the soil hydrophysical properties. Results showed significant differences between land use systems and seasons for hydraulic conductivity (K), infiltration capacity (fp) and cumulative infiltration (fc). There were no seasonal differences in soil penetration resistance (SPR), bulk density (ρd) and total porosity (φP). Grassland presented higher values for ρd (1.2 g cm⁻³) and SPR (5.3 kg cm⁻²) and lower for K (0.8 × 10⁻⁵ cm s⁻¹) and φP (53%), unlike thornscrub. Agriculture presented lower SPR (0.4 kg cm⁻²), while plantation showed similar values when compared to the thornscrub. Kostiakov infiltration model was fitted to land use infiltration curves, showing differences between land use and season. The values for fp oscillated between 53.6 and 548.8 mm hr⁻¹ and fc ranged from 105.3 to 1,061 mm. The order of the infiltration values goes as follows: agriculture > plantation > thornscrub > grassland. Land use changes in Vertisols induced modification of soil physical properties affecting processes like permeability, soil compaction and water availability.

Degradation of slopes due to shallow landslide and the subsequent erosional processes are a big challenge on the application of soil bioengineering techniques; that is the use of plants as main structural components of a slope protection and conservation system. An optimal application of soil bioengineering techniques should include not only the technical factor of plants as structural components but also the ecology of species and the plant adaptations to disturbances, which is crucial if a longterm successful slope restoration system is intended. Ferns are a dominant understory vegetation species in the forest of Japan, but its characteristics and influences on the recovery of shallow landslide scars have not been fully studied yet. This study aims to find out the ecological characteristics of fern species through the calculation of ecological indicators and the quantification of the morphological features of specimens growing on disturbed and non-disturbed forest slopes in Japan. Gleichenia japonica was found as the vegetation species with biggest ecological indicators on both slopes. The analysis of morphological characteristics of the specimens growing on both sites showed that the development of the specimens is focused in below-ground characteristics. The pull-out force of Gleichenia japonica root system as an indicator of ecological adaptation to a constraint environment and morphological characteristics quality is influenced by height and root length according to the principal component analysis. The eco-morphological characteristics of species can be used as an indicator of an optimal element in soil bioengineering establishment for slope conservation proposes. The long and fibrous root system could be placed on forest roads, steep or small slopes where space limitation is an issue for the establishment of bigger species and if the slope conditions allow it, it can control soil losses due to rainfall and provide stability.

This research reveals new insights into the weather drivers of interannual variation in land surface phenology (LSP) across the entire European forest, while at the same time establishes a new conceptual framework for predictive modelling of LSP. Specifically, the random-forest (RF) method, a multivariate, spatially non-stationary and nonlinear machine learning approach, was introduced for phenological modelling across very large areas and across multiple years simultaneously: the typical case for satellite-observed LSP. The RF model was fitted to the relation between LSP interannual variation and numerous climate predictor variables computed at biologically relevant rather than humanimposed temporal scales. In addition, the legacy effect of an advanced or delayed spring on autumn phenology was explored. The RF models explained 81 and 62 % of the variance in the spring and autumn LSP interannual variation, with relative errors of 10 and 20 %, respectively: a level of precision that has until now been unobtainable at the continental scale. Multivariate linear regression models explained only 36 and 25 %, respectively. It also allowed identification of the main drivers of the interannual variation in LSP through its estimation of variable importance. This research, thus, shows an alternative to the hitherto applied linear regression approaches for modelling LSP and paves the way for further scientific investigation based on machine learning methods.

La erosión del suelo es un grave problema ambiental, pero su impacto en cárcavas como amenaza a la vida humana, ha sido poco estudiado en Indonesia. Los objetivos de esta investigación fueron analizar el riesgo de erosión en cárcavas para la mitigación de desastres y conocer la pérdida de suelo en la caldera del Monte Bawakaraeng. Se realizaron inventarios de desastres de flujos de escombros relacionados con cárcavas en la caldera de 2007 a 2017, se llevó acabo trabajo de campo y análisis de suelo. Para la pérdida de suelo se utilizó la Ecuación Universal de Pérdida de Suelo (USLE). Se determinó que existen 22 eventos de flujos de escombros relacionados a la erosión en cárcavas en los depósitos de sedimento. Los resultados mostraron que las partículas y la permeabilidad del suelo en la parte inferior de los depósitos podrían promover la erosión, en comparación con el sitio de la parte alta de la caldera. El análisis de riesgo de erosión reveló que 3.53 % del área estudiada tiene un tipo de erosión muy bajo; 12.87 % un nivel bajo; 64.06 % un nivel moderado; 0.06 % un nivel alto y 19.49 % un nivel muy alto. La construcción de sabo dam para controlar la erosión y sedimentación y el desarrollo de un sistema de alerta contra desastres debe hacerse de forma continua en el lugar.

The construction of ponds for irrigation has proliferated during last decades in Mediterranean regions. If properly constructed and managed, ponds may simultaneously meet conservation and agricultural objectives: the preservation of certain macrophytes might improve water quality for irrigation purposes. However,the effects of management are often neglected when analyzing the main drivers of organisms community structure. Here we investigated the effect of environmental variables, construction type and management practices on the occurrence of submerged macrophytes (vascular plants, charophytes, filamentous algae). Total submerged macrophyte coverage and richness did not vary with pond type, but the presence of submerged macrophytes was significantly higher in embankment ponds. Artificial ponds showed the highest charophyte richness but lowest vascular plant occurrence. Total submerged macrophyte occurrence mainly correlated with conductivity and littoral vegetation, whilst the relative importance of environmental factors was higher than variables related to pond type and management. However, embankment ponds showed the highest richness of vascular plants and filamentous algae, and artificial ponds contributed to the regional pool of charophyte species. Thus, construction pond type and management levels might be relevant to understand submerged macrophytes occurrence in manmade ponds, since the three pond types contributed to the local and regional species pool.

The 1-year seasonal distribution of Ceratium hirundinella was studied in a southern Spanish reservoir. This species grew from June 1988 to April 1989 and showed the highest density in winter, coinciding with the lowest water temperature values and with the period of water circulation. These seasonal dynamics do not accord with the typical description of C. hirundinella in temperate systems as a phytoplankton species of stratified and warm waters. We compared the factors that influenced C. hirundinella development in this system with those operating at different latitudes and concluded that the light and temperature conditions would allow C. hirundinella to grow throughout the year in this reservoir. However, the occurrence of this potential growth is probably regulated by ecological factors, such as the presence of hypolimnetic anoxic conditions and the hydraulic regime of the reservoir.

Background: Urbanized slope areas in Sierra Madre Oriental are prone to sediment related disasters mainly caused by heavy rainfall episodes during hurricane season, knowledge on the factors on soil-roots dynamics are required to mitigate or lessen those disasters. Questions and hypothesis: The mechanical properties of roots of native species vary according species. The mechanical properties of the roots are influenced by the morphology of root: diameter. Species studied: Quercus rysophylla , Pinus pseudostrobus and Acacia berlandieri . Study site and dates: Sierra Madre Oriental, Chipinque National Park in Monterrey, Nuevo Leon. From middle of December 2014. Methods: Selection of species was made base on widespread distribution and predominance in degraded areas. Samples were taken at field and tensile tests to calculate maximum force to root breakage were conducted using a laboratory dispositive, calculations of tensile strength and modulus of elasticity were calculated using formulas. The corresponding relations between root diameter and mechanical properties were established. Results: Results confirmed that bigger diameters require bigger forces to break. In other hand, results confirmed the negative relationship between diameter and tensile strength and diameter and modulus of elasticity. Pointing out that roots of bigger diameter have less tensile strength and elasticity. The order of importance of the species studied according its mechanical properties was found like: Acacia berlandieri > Quercus rysophylla > Pinus pseudostrobus . Conclusions : The results of this study begin the data contribution of the mechanical properties of native species of Sierra Madre Oriental in order to use it in the application of soil bioengineering practices on urbanized slopes prone to disasters.

Ceratium hirundinella has traditionally been characterised as a species that thrives in warm waters and in stratified conditions. In our study, however, we found that the temporal occurrence of C. hirundinella in Spanish reservoirs greatly differs from that typically described in temperate zone aquatic systems. We analysed the temporal occurrence of C. hirundinella populations as well as physical and chemical variables in one hundred Spanish reservoirs. C. hirundinella was present in most (74%) of the reservoirs. In 78% of the reservoirs with C. hirundinella occurrence, the species was present during winter time and in 70% it was present during all four seasons.C. hirundinella was very commonly present in Spanish reservoirs in winter time despite the mixing conditions and lower temperatures and light availability. The presence of the species was positively related to water ionic content (HCO3−, SO42-, Ca2+, Mg2+). We conclude that C. hirundinella temporal occurrence in southern north-temperate systems greatly differs from the seasonality typically described for the temperate zone and could be regulated by different factors than those operating in the northern north-temperate zone.

Each intercity long-haul truck in the U.S. idles approximately 1,800 hrs per year, primarily for sleeper cab hotel loads. Including workday idling, over 2 billion gallons of fuel are used annually for truck idling. NREL's CoolCab project works closely with industry to design efficient thermal management systems for long-haul trucks that keep the cab comfortable with minimized engine idling and fuel use. The impact of thermal load reduction technologies on idle reduction systems were characterized by conducting thermal soak tests, overall heat transfer tests, and 10-hour rest period A/C tests. Technologies evaluated include advanced insulation packages, a solar reflective film applied to the vehicle's opaque exterior surfaces, a truck featuring both film and insulation, and a battery-powered A/C system. Opportunities were identified to reduce heating and cooling loads for long-haul truck idling by 36% and 34%, respectively, which yielded a 23% reduction in battery pack capacity of the idle-reduction system. Data were also collected for development and validation of a CoolCalc HVAC truck cab model. CoolCalc is an easy-to-use, simplified, physics-based HVAC load estimation tool that requires no meshing, has flexible geometry, excludes unnecessary detail, and is less time-intensive than more detailed computer-aided engineering modeling approaches.

The epilithic diatom assemblages studied in the high mountain lake “La Caldera” (Granada, Spain) from 1996 to 1998 went through two clearly different stages. The initial one, in 1996, corresponded to the reflooding of the basin after a severe drought and was composed mainly of the colonising species Fragilaria rumpens, together with a lesser presence of Nitzschia sublinearis and Hantzschia amphioxys. The predominant presence of F. rumpens at the end of the summer of 2006 coincided with low species diversity (values of Shannon and Wiener Index: 0.3-0.6). During the following two years another assemblage established itself, dominated by Achnanthidium minutissimum, which is considered to be more stable and widespread among the lakes of the Sierra Nevada. The most notable subdominant species (less than 20% of relative abundance) in this assemblage were: Encyonema minutum, Encyonopsis microcephala and Navicula cryptocephala. The diversity values during this second period were much higher than in the first: 1.0-2.2. Nutrient concentrations were measured separately in the limnetic (epilimnetic) and benthic (epilithic) environments. These abiotic parameters show that the dynamics of ammonia and silica were much the same in both, showing a gradual decrease from the beginning to the end of the study period. Epilimnetic phosphorus followed a similar pattern to ammonia and silica. In the epilithon, nitrates and phosphates increased during the first year, only to descend notably during the second. The effect of other environmental parameters such as temperature and the preceding drought on the dynamics of the diatom assemblage are discussed. Ratio DIN:SRP let us test the different degrees of phosphorus limitation in epilithon and epilimnion environments; our results suggest that phosphorus limitation of primary production in high mountain lakes is much more severe in the limnetic environment that it is in the epilithon., Chemical analyses were funded by the European project Mountain Lake Research (MOLAR).

In this paper we de cribe tbe main features of th.e size-abundance distribution andtaxonomic structure of plankton in an oligotrophic, high mountain lake (La Caldera, Sierra Nevada,Spain). The distribution is characterized by a discontinuity in the size range between -2000 and32000 fLm 3 (cell volurne). Phytoplankton are numerically dominated by the cyanobacteria Cyanarcus sp., followed by the chrysophyte Chromulina nevadensis and the diatom Cyclotellaoce/lata. Some microplanktonic species such as the diatom Navicula radiosa were observedsporadically. The size spectrum and composition of the zooplanktonic community are dominated bythe copepod Mixodiaptomus laciniatus. On con idering biomass, however, the maximum values areassociated with the largest size clas es, dorninated by the cladoceran Daphnia pulex, Both the sizestructure and taxonomic compo ition of the planktonic cornmunity srudied are consistent withexpectations ba ed on theories relating the pattern of energy flow and trophic status in lakes.

Statistical analyses suggest that 25-50% of the salt intake of Western populations is derived from the discretionary use of cooking and table salt. Yet direct estimates of discretionary salt use by a lithium technique show that in one community in Britain this source contributed only 15% to total intake. The estimates of discretionary salt use in Finland, the United States, and Britain have been exaggerated because salt losses in cooking water were not considered. Only about a quarter of cooking salt actually enters the consumed food; allowance for this in statistical calculations makes data on dietary intake similar to those assessed from urinary sodium excretion. Daily salt intake in Britain averages about 10.7 g for adult men and 8.0 g for women, figures similar to those from countries in northern Europe. The natural salt content of food provides about 10% intake, the remaining 75% being derived from salt added by manufacturers; drinking water provides a negligible amount. Any programme for reducing the salt consumption of a population should therefore concentrate primarily on a reduction in the salt used during food processing.

In order to evaluate latitudinal differences in the relationship of phytoplankton biomass and diversity with environmental conditions in shallow lakes, we sampled 98 shallow lakes from three European regions: Denmark (DK), Belgium/The Netherlands (BNL) and southern Spain (SP). Phytoplankton biomass increased with total phosphorus (TP) concentrations and decreased with submerged macrophyte cover across the three regions. Generic richness was significantly negatively related to submerged macrophyte cover and related environmental variables. Zooplankton:phytoplankton biomass ratios were positively related to submerged macrophyte cover and negatively to phytoplankton generic richness in DK and BNL, suggesting that the low generic richness in lakes with submerged macrophytes was due to a higher zooplankton grazing pressure in these regions. In SP, phytoplankton generic richness was not influenced by zooplankton grazing pressure but related to conductivity. We observed no relationship between phytoplankton generic richness and TP concentration in any of the three regions. The three regions differed significantly with respect to mean local and regional generic richness, with BNL being more diverse than the other two regions. Our observations suggest that phytoplankton diversity in European shallow lakes is influenced by submerged macrophyte cover indirectly by modulating zooplankton grazing. This influence of submerged macrophytes and zooplankton grazing on phytoplankton diversity decreases from north to south.

This chapter is based on the premise that the precipitous decline in freshwa- ter wetlands and species can only be arrested through conservation and sus- tainable management at a large scale, based on water (usually river) basins. A number of approaches to large-scale freshwater wetlands conservation are presented and assessed to draw conclusions on future conservation priori- ties.

We analyzed the changes in epilimnetic total nitrogen (TN), total phosphorus (TP), dissolved inorganic nitrogen (DIN), and soluble reactive phosphorus (SRP) in 31 small high-mountain lakes in the Sierra Nevada (Spain) during an annual cycle, just after the spring thaw, and in the middle of the growing season. Chlorophyll a, TN, and TP increased, whereas the TN:TP ratio fell substantially between the two periods, reaching values generally between 25 and 10 (by weight). On the contrary, DIN, SRP, and DIN:SRP ratios were similar for both periods in each lake. DIN:SRP ratios generally ranged from 5 to 20 (by weight). This ratio was low in the lakes with small catchment areas and increased progressively with catchment basin size. A regression analysis for the smallest catchments showed that chlorophyll a concentrations were not accounted for by variability in TP concentration. The results obtained are discussed in relation to the influence of episodes of Saharan dust, rich in P, reaching the Southern Mediterranean area. Resume : Nous avons analyse les variations de l'azote total (NT), du phosphore total (PT), de l'azote inorganique dissous (NID) et du phosphore soluble reactif (PSR) de l'epilimnion de 31 petits lacs de haute montagne de la Sierra Nevada (Espagne) pendant un cycle annuel, tout juste apres le degel du printemps et au milieu de la saison de croissance. Les concentrations de chlorophylle-a, de NT et de PT ont augmente tandis que le rapport NT:PT a diminue de facon appreciable entre les deux periodes pour atteindre des valeurs se situant generalement entre 25 et 10 (en poids). Au contraire, les concentrations de NID et de PSR de meme que le rapport NID:PSR etaient semblables au cours des deux periodes et dans chaque lac. Le rapport NID:PSR se situait generalement entre 5 et 20 (en poids). Le rapport etait faible dans les lacs a bassin versant peu etendu et augmentait progressivement avec la superficie du bassin. Une analyse de regression portant sur les bassins les plus petits a montre que les concentrations de chlorophylle-a ne se refletaient pas dans la variabilite de la concentration de PT. Les resultats obtenus sont traites dans le contexte de l'influence de vents en provenance du Sahara qui transportaient de la poussiere, riche en P, et atteignait le sud de la Mediterranee.