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How does precipitation pattern affect annual tree growth? A multi year data analysis a case study of semi arid Yatir Forest, Israel

How does precipitation pattern affect annual tree growth? A multi year data analysis a case study of semi arid Yatir Forest, Israel

Climate change associated recurring phenomenon of drought causes a threat to the global forest resource. Particularly in arid and semi-arid regions, the climate change forecast predicted a decrease in annual precipitation (P) and an increase in the intensity of rainstorms. The impact of such P pattern changes on the growth of arid and semiarid forests, where water availability is the primary growth controlling factor is not fully understood. In this study, we investigated the effect of the P pattern on soil water content (SWC) dynamics in relation to the respective tree radial growth. The study was conducted in Yatir Pinus halepensis plantation forest in the semi-arid region of Israel. Long-term meteorological, measured SWC and dendrochronological data sets and field observations have been used for subsequent analysis of P pattern, soil moisture dynamics and tree radial growth response. Inter-annual and intra- annual P pattern characterized by annual P, seasonal (monthly) P, storm characteristics (number of storms, P amount), Length of the rainy season (LRS) and length of the dry season (LDS). Higher temporal variability in annual P (CV=36%) and seasonal P (monthly P). Annual P of the last 5 decades did not show a statistically significant trend of change. However, the number of storms (NS) show decreasing trend attributed to the smaller and frequent storms with < 5 mm which have < 10% contribution to the annual P. Dry, intermediate and wet years showed a significant difference (p=0.01) in NS while there was no significant difference in LRS and LDS. This difference in storm pattern distribution clearly reflected on the soil water dynamics variation among wet, intermediate and dry years. Wet, intermediate and dry years have about four, two and one months of growing length seasons, respectively. To conclude, annual P, NS, LRS, LDS and length of the growing season were a significant predictor of tree radial growth. But P was the best predictor of the most parsimonious model for tree radial growth (BAI). Monthly distribution of these bigger and infrequent storms determines the SWC seasonal dynamics and respective GSL of the HY.

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Modes of functional biodiversity control on tree productivity across the European continent

Modes of functional biodiversity control on tree productivity across the European continent

Figure S4.6. The absolute influence of each predictor on plot-level tree growth (m 2 ha -1 yr -1 ) across the continent. The predictors are: annual mean temperature; mean annual precipitation; functional dispersion; community-weighted mean (CWM) maximum height; CWM leaf N content; CWM maximum life span; and CWM wood density. The covariates (plot basal area (m 2 ha -1 ), mean tree size (mm), species pool and natural mortality rate (m 2 ha -1 yr -1 ) have been group together in grey and labeled covariates. The white panel indicates missing values. The data is aggregated at 1 ° latitude.

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Coupling socioeconomic processes with climate models: a parameterizacion for the community earth system model (CESM)

Coupling socioeconomic processes with climate models: a parameterizacion for the community earth system model (CESM)

dhj In addition to maintaining the model's integrity, the new parameterization has resulted in better results in areas of the planet where models repeatedly fail. Thus, for example, the UCLM-CESM captures the precipitation structure in key regions, such as the El Niño 4 region, better than the standard version of the model (Figure 3.35). In addition, it has managed to more realistically reproduce the intra-annual precipitation cycle over the 20S-0 zone, 80E-100W of the southern hemisphere (Figure 3.36A). This is an important step forward as it reduces the effect of the double ITCZ, which is very common in models. Other minor improvements are in the Tibetan Plateau (3.36C) where models always overestimate the total amount of precipitation, and in Australia's Top End (3.36B). In the case of the Tibetan plateau, the main problem lies in the complexity of its orography, which prevents the models from accurately solving the amount of precipitation. For the Top End, the problem is that the models do a poor simulation of the monsoon in Southeast Asia and Oceania.

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Vol. 5, núm. 1 (2014)

Vol. 5, núm. 1 (2014)

This report presents information on the hydro-climate temporal and spatial variability for the State of Durango, Mexico. Annual rainfall data fitted the Gamma probabilistic density functions. The Gumbel-Fisher-Tipett density function fitted maximum daily precipitation. The log-Pearson Type III density function projected maximum annual discharge and daily maximum peakflows. Evapotranspiration was estimated by the Thornthwaite methodology. More than 80 climatic stations with data lasting longer than 30 years were used to fit probability density parameters. Geographical prediction equations; e.g. mean annual rainfall = α + β1 (Latitude) +β2 (Longitude) + β3 (Altitude) estimated the spatial variability of precipitation, temperature and evapotranspiration. Reconstructed and instrumental long- term (1860-2004) time series (precipitation and streamflow) data was temporally analyzed using ARIMA and linear and nonlinear regression techniques. Results showed mean annual temperature and evapotranspiration are spatially variable, diminishing with an increment in latitude and altitude. Mean annual precipitation on the other side increases with latitude and altitude but reduces with longitude. This trend was reversed for the Pacific Ocean physiographic region. Hydro-climatic data showed a lack of linear monotonic patterns indicating the time series are stationary in the first momentum. Oscillations of several time-scales: seasonal, inter-annual, 3-7 years; and 9-12- year were consistently noted on the modeled reconstructed and instrumental time series, spectral density analysis and correlograms for annual precipitation and streamflow data. Large-scale synoptic climate events such as the seasonal monsoon, the inter-annual variability, the El Niño Southern and the Pacific Decadal Oscillations appeared to explain temporal oscillations. Spatial variability was observed in hydro-climatic maps constructed using GIS techniques. This spatial and temporal information can be used in the decision making of water management resources at the local and State spatial scales; and in studies of productivity, forest wildfires, and floods of the State of Durango, Mexico.

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Relación entre la estructura genética del sapo andino Rhinella spinulosa (Anura: Bufonidae) y el paisaje del norte de Chile (21°  24° S)

Relación entre la estructura genética del sapo andino Rhinella spinulosa (Anura: Bufonidae) y el paisaje del norte de Chile (21° 24° S)

O u r s t u d y s h o w s t h a t i n c o r p o r a t i n g landscape features in a biogeographic and small scale context produces a greater understanding of the processes occurring at different levels. While between all localities Euclidean distance and annual precipitation were related to genetic differentiation at a larger spatial scale, altitude, temperature and wetland based route, were related at a smaller spatial scale. Probably the same variables appear to be related to events that occurred in a more recent time. The altitude dif ference has been related with genetic dif ferentiation in amphibians inhabiting mountain regions, showing high levels of population differentiation (Funk et al. 2005, Spear et al. 2005). In this case, it would also be a relevant factor, that does not allow the dispersal of R. spinulosa, as is shown in nearby populations (Peine and Tilomonte). This effect will be reduced when other factors can

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Absolute homogeneity assessment of precipitation time series in an arid region of Pakistan

Absolute homogeneity assessment of precipitation time series in an arid region of Pakistan

Homogeneity evaluations are usually performed on the total annual precipitation data, which often fails to detect non-homogeneity in seasonal precipitation. Furthermore, it is required to assess homogeneity using multiple methods as the performance of homogeneity testing methods depend on the distribution of the data. This is particularly important for the arid region where distributions of seasonal and annual rainfall are often non-normal. The homogeneity of annual and monthly precipitation datasets of 14 meteorological stations located in the arid region of Pakistan was assessed in this study using the Pettitt’s test, the standard normal homogeneity test (SNHT), the cumulative deviation test, the von Neumann’s ratio test, the Bayesian test, the Worsley’s likelihood ratio test, and Student’s t-test at a 95% confidence level. The rainfall series were categorized into three classes, namely “useful”, “doubtful” and “suspect” based on the results of different homogeneity tests. Results suggest that rainfall time series for most of the months in all the stations are

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Multivariate standardized indices   application beyond drought detection for operational drought management in semi arid regions in the Americas

Multivariate standardized indices application beyond drought detection for operational drought management in semi arid regions in the Americas

49 are far-reaching and long-lasting, as trees need to be replanted, groundwater systems need to recover, and agricultural areas must be cultivated. Another example is the Millennium Drought in Australia (1997–2009), a precipitation deficit that is linked to El Niño conditions, which changed interactions in the hydrological cycle for years. Mitigation programs that were implemented during the event minimized losses (e.g., open water markets, public water restrictions, new desalination plants) and initiated a paradigm shift in the perception of Australians society towards a pro-active behaviour [3,4]. These are only two examples which highlight the importance of drought monitoring as one component of drought management. We understand drought monitoring as an essential part of drought management, and studying drought propagation as part of drought monitoring, as it incorporates the relation between variables in the study area. Hence, as drought propagation patterns are studied, drought monitoring could be improved as warning signals can be noticed. Further, the monitoring systems of the United States (US) and Australia are guiding examples for drought monitoring worldwide, and still, negative impacts occur and even exceed previous ones. Taking those two examples, for which the causes (combination of high temperatures in California and El Niño–Southern Oscillation (ENSO) influence in Australia) were detected afterwards, are serving as examples for the necessity of broadening drought monitoring and including propagation patterns.

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Annual report 2012

Annual report 2012

The Mobility Observatory is a working group promoted jointly by the Ministry of Agriculture, Food and the Environ- ment and by the Ministry of Public Works, which brings together the transport authorities of around twenty met- ropolitan regions of Spain. As well as being a discussion group that organizes seminars on matters of interest to the participants, it publishes the annual journal Obser- vatorio de la Movilidad Metropolitana, which sets out a compilation of a number of indicators from all the regions. This is a useful tool as it permits a comparison between the different metropolitan conurbations of the State. It is comparable to the EMTA barometer referred to above, but on a Spanish scale.

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Changes in rainfall patterns on the upper Ecuadorian Andean mountains: Analysis of extreme precipitation, ENSO effects and shifts of annual rainfall variation

Changes in rainfall patterns on the upper Ecuadorian Andean mountains: Analysis of extreme precipitation, ENSO effects and shifts of annual rainfall variation

Rainfall in the upstream drainage area of the Ecuadorian Andean Mountains (EAM) is an important source of runoff for the main hydropower projects. Although understanding the interaction between rainfall-runoff processes is a difficult task, it is important to understand these mechanisms in order to manage water resource projects. Although there are several local and regional mechanisms that control seasonal, annual, decadal and extreme rainfall variation, it is important to analyze the tools that are widely used in the hydraulic design of hydropower structures. Among other statistical resources, hydraulic civil engineers use the Gumbel Method to study extreme precipitation events, as well as mean and median statistical values to evaluate water availability in the design of a project. In addition, the analysis of rainfall-runoff processes depends on data availability. The main question at the heart of this study is: How can rainfall trends in the highlands of the Ecuadorian Andean Mountains be integrated to rainfall design of hydraulic structures of hydropower projects? The justifications of this question are as follows: First, the occurrence of extreme precipitation events increases the risk of flooding, resulting in the failure of the spillway’s dams. Second, changes in annual rainfall variation could lead to water scarcity in the management of water resource projects. Additionally, we compared the extreme precipitation events with ENSO years. This study focuses on improving the understanding of rainfall trends at EAM and its implications in the management of hydraulic structures.

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Annual Report 2012

Annual Report 2012

• Area of Women and Positive Creation: Delivery of the 2011 Annual Report (February) • Federation of Catalan Organisations of The Elderly, Women and Family (FOCAGG) • 7th edition of the United Nations Model, Barcelona 2012 (C’MUN), organised by the Association for the United Nations in Spain

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Annual report 2009

Annual report 2009

In 2009 the metropolitan assignment for the control of discharges into the Barcelona sewer system resulted in a total of 707 (one off and integrated) inspections, of different companies working within both the municipal area of Barcelona and also its adjacent metropolitan areas, which represented a significant increase in comparison with previous years. In line with previous years, however, this work also included the collection of 288 samples from drains and water treatment plants, an emergency discharge service (24 hours/365 days) and the publishing of an annual edition of an atlas of potentially contaminating establishments in the Barcelona area. As an outstanding innovation in 2009, we must stress the work of establishing the bases for the future EMSHTR remote control drainage network water quality system. This work is set to continue in the implementation phase throughout 2010.

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Annual report 2006

Annual report 2006

This annual report contains a description of a whole number of critical situations within its pages, each one efficiently resolved by the Barcelona Fire Brigade corps. We must be aware of the human factor behind all the numbers and figures, the distress of individuals who have suffered serious fright or calamity. What I mean is that the Fire Brigade is one of the services that most directly touch the human soul, the extreme experience. Year after year, according to the public opinion polls, it turns out to be one of the most valued services in the city. This says a lot for the professionalism and vocational integrity of the people who staff it.

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Potential distributional patterns of three wild ungulate species in a fragmented tropical region of northeastern Mexico

Potential distributional patterns of three wild ungulate species in a fragmented tropical region of northeastern Mexico

Roads may positively or negatively influence deer distribution through either avoidance [43], or possible attraction because some plants eaten by white-tailed deer might be abundant near roads [44]. Similarly, water sources have been regarded as a key habitat element for the species [18]. The lack of contribution of these two variables to our potential distribution model is likely related to the relatively large scale of our model. Our sources of geographical information do not represent some water reservoirs such as concave rocks, natural or artificial depressions and small natural dams, which contain rain water throughout most of the year. These elements are locally more important than the large water bodies that we identified in the Landsat images. Our model also failed to identify slope and aspect as critical determinants of white-tailed deer potential distribution at the regional scale in spite of their reported importance at local scales [17,27,28]. While slope and aspect could influence this species at the local scale [17], at the regional scale these variables may be irrelevant. Soil type, however, was the second most important variable for this species at the scale of our analysis, followed by isothermality and precipitation seasonality (Table 3). Along with topography, these factors determine the structure and function of ecosystems, and thus influence fundamental habitat features.

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Annual report = Mémoire annuel  2012

Annual report = Mémoire annuel 2012

Barcelona has the strength to spearhead the economic recovery of our country. We have all the necessary assets; growth, innovation and competitiveness that can only be generated in large cities which, like ours, have the desire to improve. I am therefore pleased to present the 2012 Annual Report of El Consorci, be- cause without doubt, El Consorci is one of the most committed public agents in this mission and has always provided solutions to the challenges of our city. We all know that 2012 has been a critical year, which has implied taking rigorous and austere measures. The loss of occupancy has made it imperative to give priority attention to people and, in turn, has demanded that we maintain our strategic path towards regaining the economic boost.

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