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The increasing demand for water resources in arid and semiarid countries has stimulated the use of non-conventional water resources such as reclaimed water. Consequently, turfgrass irrigation with reclaimed water has become a regular practice in these regions. The main goal of this research was to assess the effects of reclaimed water (RW) irrigation in Madrid urban parks by studying changes in grass nutrient balance and its biomass production. Irrigation with reclaimed water led to a grass biomass increase, mainly due to the high proportion of nutrients received through the irrigation water. The main nutrient input in RW irrigation were of Cl, S, K and Na. RW also contributed to a significant increase in nutrient removal by grass. Thus, all this information generated should be taken into account by park managers in order to fulfill the grass aesthetic value and its nutritional requirements in those urban parks irrigated with RW., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Mediterranean vineyards are usually managed with continuous tillage to maintain bare soils leading to low organic matter stocks and soil degradation. Vineyards are part of the Mediterranean culture, their management can be sustainable. We propose the setup of two types of groundcovers with the aim to assess their potential influence to improve soil properties. A field trial was performed to compare the effects of a seeded (Brachypodium distachyon) and spontaneous groundcovers, on a set of soil parameters, in comparison with the traditional tillage in four vineyards located in the center of Spain. Three years after the groundcovers establishment soil organic carbon stocks increased up to 1.62 and 3.18Mgha -1 for the seeded and the spontaneous groundcovers, respectively, compared to conventional tillage. Both labile and stable fractions improved their soil organic carbon content with the use of groundcovers, particularly the labile fraction. Moreover, soil structure and functional soil properties improved through better aggregate stability, pore connectivity and infiltration rates. The higher root biomass input of the spontaneous groundcovers derived in higher soil organic carbon increases and soil quality improvement. Consequently, under low rainfall conditions (<400mmperyear) spontaneous vegetation, properly managed according to site conditions, is an effective soil management strategy to revert soil degradation and increase soil quality in Mediterranean vineyards., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Hypoxia-inducible factor-1alpha (HIF-1alpha) protein is degraded under normoxia by its association to von Hippel-Lindau protein (pVHL) and further proteasomal digestion. However, human renal cells HK-2 treated with 15-deoxy-Delta(12,14)-prostaglandin-J(2) (15d-PGJ(2)) accumulate HIF-1alpha in normoxic conditions. Thus, we aimed to investigate the mechanism involved in this accumulation. We found that 15d-PGJ(2) induced an over-accumulation of HIF-1alpha in RCC4 cells, which lack pVHL and in HK-2 cells treated with inhibitors of the pVHL-proteasome pathway. These results indicated that pVHL-proteasome-independent mechanisms are involved, and therefore we aimed to ascertain them. We have identified a new lysosomal-dependent mechanism of HIF-1alpha degradation as a target for 15d-PGJ(2) based on: (1) HIF-1alpha colocalized with the specific lysosomal marker Lamp-2a, (2) 15d-PGJ(2) inhibited the activity of cathepsin B, a lysosomal protease, and (3) inhibition of lysosomal activity did not result in over-accumulation of HIF-1alpha in 15d-PGJ(2)-treated cells. Therefore, expression of HIF-1alpha is also modulated by lysosomal degradation.

This project takes a look at the variation of the parameters related to soil erodibility (fractions of clay, silt, fine and coarse sand; organic matter, permeability, and structure) coming from soil pits from the Community of Madrid's soil map (Spain), according to Soil Taxonomy at subgroup level. It draws the conclusion that map erodibility shouldn't be estimated from a soil map because the K factor obtained does not present significant differences among the different types of soil. One or more key factors related with soil erodibility must be taken into account if erodibility maps are to be drawn. This research has shown that silt and structure could be considered key factors for erodibility maps of the area, but not significant differences have been found in important factors such as clay or organic matter due to the wide range of data variance. In order to elaborate erosion risk maps the use of the K factor from the physiographical map is a good alternative. When data are grouped according to these criteria significant differences in K factor are shown. Erodibility was greater in soils developed over gypsic material, with a value of 0.63+/-0.28, than in high plateaus (locally know as alcarrias), with a value of 0.40+/-0.18. In order to adequately represent soil erodibility, a kriging geostatistic technique is used, which reduces the variation of the factors considered when they are found to correlate, as is the case with the parameters considered to calculate K factor.

The erosive power of frequent light rainfalls is studied in this paper. Field experiments of simulated rainfall (Intensity, 21 mm h(-1) and kinetic energy, 13.5 J m(-2) mm(-1)) were conducted over 8 bounded USLE plots (80 m(2) each) with a slope of 10%. In 4 plots the soil was almost bare (<4% vegetation cover); the other 4 plots had almost full cover with natural vegetation in one year. Runoff and sediment yield was recorded. The results revealed the efficiency of vegetation cover reducing runoff and sediments. Runoff and sediments were negligible in covered plots. Therefore, in bare plots, although sediment yield was generally low, averaging 74+/-43 kg ha(-1), the mean of runoff achieved a coefficient of 35%, this magnitude has to be taken into consideration in this region verging on aridity. Rains around 13.5 J m(-2) mm(-1) of kinetic energy are quite frequent in the study area (34% of recorded rains en 12 years). If we would consider the usual lower limits from the literature, we would be ignoring an important percent of natural rainfall episodes.

The rate of soil erosion in pine forests (Pinus halepensis) located in the Southeast of Madrid has been estimated using dendrochronological analysis based on the change in ring-growth pattern from concentric to eccentric when the root is exposed. Using 49 roots spread across five inclined areas, it has been found that the length and direction of the hillsides, as well as their vegetation cover affect the rate of erosion, while the slope itself does not. The erosion rates found for the different areas studied vary between 3.5 and 8.8 mm year(-1), that is between 40 and 101 t ha(-1) year(-1) respectively. These values are between 2 and 3 times greater than those predicted by USLE, for which this equation underestimates soil loss for Central Spain's Mediterranean conditions. Nonetheless, both methods (using dendrochronology to determine actual soil loss and theoretical prediction with USLE) are able to establish the same significant differences among the areas studied, allowing for the comparative estimate of the severity of the area's erosion problem.