Remote mountain lakes as indicators of diffuse acidic and organic pollution in the Iberian peninsula (AL:PE 2 studies)

In the framework of the AL:PE 2 project, studies on acidification and organic pollution in mountain lakes have been conducted in several ranges in the Iberian peninsula: Pyrenees (Northeastern Spain), Sierra de Gredos (Central Spain), Sierra Nevada (Southern Spain) and Serra da Estrela (Central Portugal). These studies focused on water and sediment chemistry and organisms (benthic diatoms, Zooplankton, aquatic macroinvertebrates, and fish) as indicators of acidification. Organic micropollutants (PAH, PCB, DDE, hexachlorobenzene and others) in lake sediments and fish have been studied as tracers of atmospheric pollution. The Iberian peninsula lakes do not show severe anthropogenic acidification. pH values are in the range of sensitive lakes, but the levels of acidic pollutants are low. The status of the organisms surveyed agreed with this diagnosis. Pyrenean lakes showed the highest fluxes of organic pollutants related to fossil fuel combustion., higher pollutioninduced versus natural acidity ratios, and modeled alkalinity and pH declines.     

A note on the nutritional status of the rice plant in Italy,Portugal, and Spain

In the rice area around Velcelli, grain yields are reasonably high due to good management, and a situation similar to that of the “Akiochi” area in the western part of Japan is prevailing.

In coastal areas of Spain and Portugal, rice yields are frequently very high due to the abundance of solar radiation. In these areas, however, if soil management is inadequate, rice suffers from NaCl injury, zinc deficiency, iron toxicity, or boron toxicity due to the nature of the soils and the influence of brackish water.     

The effects of land uses on soil erosion in Spain: A review

Soil erosion is a key factor in Mediterranean environments, and is not only closely related to geoecological factors (lithology, topography, and climatology) but also to land-use and plant cover changes. The long history of human activity in Spain explains the development of erosion landscapes and sedimentary structures (recent alluvial plains, alluvial fans, deltas and flat valleys infilled of sediment). For example, the expansion of cereal agriculture and transhumant livestock between the 16th and 19th centuries resulted in episodes of extensive soil erosion. During the 20th century farmland abandonment prevailed in mountain areas, resulting in a reduction of soil erosion due to vegetation recolonization whereas sheet-wash erosion, piping and gullying affected abandoned fields in semi-arid environments. The EU Agrarian Policy and the strengthening of national and international markets encouraged the expansion of almond and olive orchards into marginal lands, including steep, stony hill slopes. Vineyards also expanded to steep slopes, sometimes on new unstable bench terraces, thus leading to increased soil erosion particularly during intense rainstorms. The expansion of irrigated areas, partially on salty and poorly structured soils, resulted in piping development and salinization of effluents and the fluvial network. The trend towards larger fields and farms in both dry farming and irrigated systems has resulted in a relaxation of soil conservation practices.     

The effects of land use and climate on red kite distribution in the Iberian peninsula

The main breeding populations of the red kite (Milvus milvus L.), have been declining in the Iberian peninsula during the last decade. However, there is a lack of regional assessments of habitat suitability that identifies limiting ecological factors for the species and areas with conservation problems. In this work we present a regional model for the distribution and abundance of breeding red kites in the Iberian peninsula. The occurrence and estimated abundance in 100 km² UTM squares resulting from road censuses were modelled with broad-scale explanatory variables obtained from satellite imagery, thematic digital cartography, climatic data and spatial coordinates. The occurrence model incorporated mainly climatic variables and had a good discrimination ability, while the abundance model incorporated mainly land-use variables and had a lower explanatory power (r²=0.14). The predictions somewhat overestimated the results of the censuses, and this agrees with the decline of population size and range observed for this species in the Iberian peninsula. These models are relevant in the conservation of the species: first, they suggest the limiting factors for red kite in the Iberian peninsula, and, second, they generate predictive maps pointing out both areas in which conservation problems may be acute (suitable locations that are unoccupied), and areas where no data is available but the red kite is likely to be present (thus guiding further survey and research).     

Removal of Acid Orange 7 Dye from Water Via Plasma-Polymerized Allylamine-Coated Quartz Particles

Environmental pollution is one of the most serious causes of degradation of Mediterranean wetlands. Mercury (Hg) and cadmium (Cd) are of particular concern due to biomagnification. Here, we used red swamp crayfish (Procambarus clarkii) to monitor the spatial and temporal patterns of these two metals in a Portuguese rice field system. We sampled the crayfish in three different sites and three different time periods in the Sado River Basin (Portugal). We measured temperature, pH, total dissolved solids and conductivity in the water. Hg and Cd were measured in the crayfish abdominal muscle tissue and exoskeleton. In muscle, a spatial pattern was found for the accumulation of Cd while for Hg, only a temporal pattern emerged. The spatial pattern for Cd seemed to reflect the mining history of the sites, whereas the temporal pattern for Hg seemed related to the flooding of rice fields. We suggest that this flooding process increases Hg bioavailability.     

Analysis of the distribution of endemic and rare arthropods in high endemism areas of Algarve-South Portugal

The study of several arthropod groups in high endemism areas (HEA) of Algarve, the Southernmost province of Portugal, has revealed endemic species and species not yet recorded for the Portuguese fauna. The list includes 3 species of Isopoda endemic to Algarve, to Portugal or to the Iberian Peninsula, 2 species new to Portugal and 2 species new to the Iberian Peninsula; 2 species of Pseudoscorpiones not yet cited to Portugal; 11 species of Pauropoda new to Portugal, including one new species probably endemic; 15 species of Collembola endemic to the Portuguese or to the Iberian Peninsula faunas (Gama et al. 1997) and 37 species and 5 subspecies of Staphylinidae endemic to Algarve.With the exception of Collembola, which have been studied by us, the remaining groups have been submitted for study to several specialists.These findings heighten the biological richness of these areas of high endemism in terms of conservation of biological diversity. The authors draw attention to the necessity to preserve or restore the biological value of these areas, encouraging the adoption of protective measures and the creation of research programmes that include the implementation of taxonomic studies and co-operation between taxonomists and ecologists in order to preserve the biodiversity of these areas.     

Gully erosion associated with the expansion of unterraced almond cultivation in the coastal Sierra de Lujar,S. Spain

Since Moorish times, the lower slopes of the Sierra de Lujar in southern Spain have been intensively cultivated. Despite steep slopes and the highly erodible nature of the local micaschist/quartzite bedrock and derivative Quaternary sequences, accelerated erosion has largely been contained throughout this history by substantial, well-maintained rock terraces. However, since 1987, European Union (EU) agricultural policy has been to encourage the cultivation of certain crops by subsidising their expanded cultivation on a ‘per hectare’ basis. This has resulted in hasty clearance of native Mediterranean matorral on sites really unsuitable for the local staple crop (almonds), and erosion-prevention terraces are often absent or rudimentary. Gullying is now a very serious problem on some of these newly cleared sites. This paper identifies the lithological, topographic and agricultural policy controls on the consequent gully distribution, and then explores the pedological and hydrological controls on gully initiation on a single unterraced slope. Using these results alongside morphological data from gully surveys, a gully initiation and growth model is presented. This suggests that two types of gully are present in the area. ‘Type 1’ or upper-slope gullies are initiated by overland flows, which are relatively infrequent. By contrast, ‘type 2’ or slope-base gully initiation involves saturation and collapse in fossil landslip scars in Holocene colluvium. These two very different morphological systems may integrate through the terminal fan of the upslope gullies, in a manner described by Tiexeira de Oliveira 1990. The implications of this are that in the study area, sediment removal is associated with a very few highly productive sites. Contemporary management is briefly assessed against this model of geomorphic change in the area.     

近40年乔戈里峰北坡冰川与气候变化关系研究

以乔戈里峰北坡冰川为研究对象,选取1978年、1991年、2001年、2014年4个时期的Landsat MSS/TM/ETM+/OLI影像,通过遥感图像计算机辅助分类和目视解译等方法提取了不同时期乔戈里峰北坡的冰川边界,并分析了乔戈里峰北坡冰川1978—2014年的进退变化。结果表明:1978—2014年乔戈里峰北坡冰川面积减小了53.37 km²,占1978年冰川总面积的6.81%,冰川近40 a在气候变暖的背景下反而呈现退缩速率由快变慢的趋势,且近10 a冰川退缩尤为缓慢,年均退缩率仅为0.12%。研究区东向冰川退缩率明显高于西向冰川,冰川退缩率随冰川规模的增大而减小,同时也随海拔高度的上升而减小。冰川变化的原因分析显示:气温升高导致研究区冰川退缩,而降水量的持续增加在一定程度上抑制了冰川的退缩;研究区内12条典型前进冰川对冰川积累区面积贡献较大,使得研究区整体冰川退缩率由快变慢的趋势更为显著。     

1990-2011年南天山地区冰川面积变化对气候的响应

利用Landsat TM/ETM⁺影像资料,通过遥感图像计算机自动解译和目视解译方法得到南天山地区1990年、2000年、2011年三期冰川边界,并应用GIS技术系统研究了南天山地区冰川近21 a来的面积变化及其对气候的响应关系。结果表明:1990—2011年期间,南天山地区冰川面积变化了-13.2%。大规模冰川分解使得小规模冰川的总面积和条数均有所增加,朝西向的冰川退缩速率最大,为-15.9%。与1990—2000年时段对比发现,近10 a来,海拔大于3 800 m的冰川退缩速率加快。通过地面气象资料的分析发现,南天山地区的气温和降水均表现出增加趋势,海拔最高的巴音布鲁克站线性升温率为0.25℃/10 a,降水增幅为1.2 mm/a。与西风区其它现有研究对比,发现南天山地区冰川的强烈退缩可能主要受到气温升高的影响,降水的增加对其影响不大。此外,地形条件和冰川规模等都是影响冰川波动的重要因素。     

Relationships between phosphate sorption and iron oxides in Alfisols from a river terrace sequence of Mediterranean Spain

Phosphate sorption isotherms for samples of the A- and upper B-horizons of Alfisols situated on a sequence of terraces of the River Guadalquivir, southern Spain, showed that phosphate sorbed at an equilibrium concentration of 0.3 μg P ml^?1 was correlated with several soil properties. Crystalline Fe-oxides (goethite and hematite) appeared to be the most important P-sorbing components of the soil samples. Sorption was highly correlated with percent clay and with dithionite soluble Fe. This last property was as good a property to predict sorption as the specific surface of crystalline Fe-oxides (which was estimated by line profile analysis of the X-ray diffractograms), probably because the range of surface areas for goethite and hematite was relatively narrow in the samples and because of the limited accuracy of the method of line profile analysis.Well drained and imperfectly drained soils differed little in sorption properties. In imperfectly drained, hematite-free soils, chroma was correlated with sorption. This is promising for it would allow rapid field estimation of sorption.The sorption maximum, calculated from the fitted Langmuir isotherm, was about 1.7 μmol P m^?2 of Fe-oxides, a value similar to those reported in the literature for natural and synthetic oxides.     

Effects of copper toxicity on growth and the uptake and translocation of metals in rice plants

Copper (Cu) contamination in the lower reaches of the Sado River in the Alcacer do Sal region of Portugal (a major rice producing area) has became a major pollution problem. In an attempt to study the changes in rice growth (Oryza sativa L.), the effect of excess Cu on the plasma membrane activity (as measured throughout proton extrusion) and membrane permeability as well as on the zinc (Zn), nitrogen (N), phosphorus (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), boron (B), molybdenum (Mo), and aluminum (Al) net uptake and translocation was studied. Long‐term studies (30 days) were conducted with rice subjected to increasing Cu concentrations (ranging from 0.002 to 6.25 mg/L) showed a concentration increase of Cu in root and shoot tissues. Root proton extrusion increased 7.4‐fold between the 0.01 and the 1.25 mg/L Cu treatments, whereas its membrane permeability (as measured throughout the electrolytic conductance) revealed a marked increase after the 1.25 mg/L Cu treatment. Zinc concentrations decreased with increasing Cu levels in the nutrient solution (excepting the 6.25 mg/L Cu treatment in shoots), while N, P, K, Na, Ca, Mg, B, Mo, and Al concentrations, although showing different patterns, did not reveal any correlation with increasing Cu level. The absolute content of all these metals as well as their net uptake exhibited (excepting Al) its highest values in the 0.25 mg/L Cu treatment. It is suggested that these variations, triggered by excess Cu on root growth, might be explained based on the interaction among Cu‐uptake mechanism(s), plasma membrane‐H⁺ ATPase and root membrane permeability. It is also suggested that Cu affects the N, P, K, Na, Ca, Mg, B, Mo, and Zn concentrations in rice shoots mainly by changing their net uptake rate.     

Rice cultivation and its environmental conditions in the Mediterranean countries II. Soils,their fertility and mineralogy

In Italy paddy aolls have a broad varfability with respect to region and age of the parent material. The regional characteristics, however, predominate over the age relations, i.e., the Po delta soils have higher potentialities than the youngest of those in the middle reaches of the Po. Among soils of the middle reaches the older the parent material, the more depleted the bases. Some of the better drained terrace soils have the morphology of “aquorizem.”

Spanish paddy soils along the Mediterranean coast are all alike, having an alkaline reaction due to the presence of free lime, and SiCL to SiC textures. Morphologically there are two types of paddy soils, one having gleyed subsoils due to groundwater influence, and the other having brown subsoils below strongly gleyed aurface soils under aubmergence.

Portugese paddy soils are generally similar to Spanish soils both in mode of occurrence and In nature, except for neutral to slightly acidic reaction and absence of free lime in the former.

The general soil potentiality aa judged from chemical and mineralogical atudies is in the order of Spanish>Portugese>Italian paddy aoils.     

Phosphorus status of some paddy soils in Bangladesh

Abstract

Phosphorus status of Bangladesh paddy soils covering the major paddy soil types was assessed in terms of parent materials and physiography. Total P concentration ranged from 172 to 604 mg kg^?1 in the topsoil and from 126 to 688 mg kg^?1 in the subsoil, and varied with the physiography to which the soils belonged. In most soils, the available P concentration was much higher for the topsoil than for the subsoil. The inorganic P concentration was higher than the organic P concentration, except for one soil series from the Old Himalayan Piedmont Plain, and was significantly and positively correlated with the total P concentration. Among the inorganic forms, only the concentration of Al-bound P showed a significant correlation with that of available P based on the Bray P-2 method in both topsoil and subsoil. In general, the P status was critically low in paddy soils of the terrace area. Normal growth of paddy rice in this area is expected to be difficult without application of P fertilizer.     

岗日嘎布地区冰川变化特征研究

以Landsat影像为数据源,通过遥感图像计算机辅助分类和目视解译方法,提取中国西部对气候变化最为敏感的西藏东南部海洋型冰川区（岗日嘎布地区）2005年,2013年冰川边界,分析了冰川变化特征及冰川变化与气候变化的响应关系。结果表明:2005—2013年冰川面积减少72.28 km²,占2005年冰川面积的15.75%;冰川分布的下限海拔高度升高61 m。结合气象资料分析认为,降水量是冰川发育规模的主要影响因素,而温度是冰川发育数量的主要影响因素,升温是研究区近年来冰川加速退缩的主要原因。由此预测未来冰川消融速率会进一步加快。     

The sediment budget of a large river regulated by dams (The lower River Ebro, NE Spain)

Purpose

The aim of this work was to develop a comprehensive fluvial suspended sediment budget for a large regulated river, the lower River Ebro (NE Spain).

Materials and methods

The sediment loads of the Ebro mainstem and its main tributaries were estimated from continuous records of water discharge and turbidity (appropriately transformed to suspended sediment concentrations). Records were obtained at ten monitoring sections during the relatively dry 2008–2011 period.

Results and discussion

The sediment load estimated for the River Ebro upstream of the Mequinenza Reservoir is remarkable (i.e. mean suspended load of 0.6?×?10⁶?t?year^?1), despite the fact that the site is already affected by a sediment deficit due to upstream reservoirs. Further downstream, and owing to their humid characteristics, the contribution of the Pyrenean tributaries (Segre and Cinca Rivers) is much larger compared with their Iberian Massif counterparts (Matarranya and Algars Rivers), with sediment loads of 0.49?×?10⁶ and 2,260 t, respectively. The suspended sediment load trapped in the Mequinenza-Ribarroja-Flix Dam Complex for the study period was estimated at 2.3?×?10⁶?t. Below the dams, the sediment load was reduced by 95 % but increased gradually in a downstream direction due to the erosion processes that clear water (i.e. very low sediment concentrations) flood flows exert on the river bed and banks and the episodic contribution from ephemeral tributaries.

Conclusions

Reservoirs have reduced the overall sediment load and the natural variability of flow and sediment transport in the River Ebro. In addition, the sediment budget revealed that floods were not the only drivers of the sediment dynamics in the lower Ebro. For instance, the particular location of the monitoring sections showed that episodic contributions from small tributaries alter the general sediment load of the river during certain torrential events.     

抗真菌转基因水稻根际土壤真菌群落结构的动态变化

以非转基因水稻"七丝软粘"为对照,采用传统平板计数法和变性梯度凝胶电泳技术,研究了抗真菌转基因水稻"转品1"和"转品8"生长周期内对根际土壤中可培养真菌数和真菌群落结构的影响。结果显示,相同生育期转基因水稻根际土壤可培养真菌数量与其非转基因对照水稻相比较无显著性差异,表明转基因水稻的种植没有对根际土壤真菌数量产生明显影响;18S rRNA真菌群落DGGE图谱分析显示,相同生育期转基因水稻与其非转基因对照水稻的根际土壤真菌DGGE条带数量和条带位置均无显著性差异,表明转基因水稻的种植没有对根际土壤真菌群落结构产生明显影响。进一步分析相同生育期转基因水稻与其非转基因对照水稻的根际土壤真菌群落香农多样性指数(Shannon diversity index)和均匀度指数(Evenness index)的动态变化,发现两者均没有显著性差异。以上研究结果表明,外源抗真菌基因的导入对水稻根际土壤中真菌群落数量和群落结构均没有明显影响。此外,将不同位置的真菌DGGE条带切胶回收,克隆、测序后,进行系统进化树分析,结果表明根际土壤真菌群落主要归属为子囊菌门(Ascomycota)、担子菌门(Basidiomycota)、壶菌门(Chytridiomycota)、接合菌门(Zygomycota)和未知真菌(unknown fungi)5个类群。     

The status of the medicinal leech Hirudo medicinalis in Europe and especially in the British isles

In spite of reports to the contrary, an analysis of 206 recent records for the years 1952 to 1982 shows that the medicinal leech Hirudo medicinalis Linnaeus is still present at one or more localities in 23 European countries (Albania, Austria, Britain, Bulgaria, Czechoslovakia, Denmark, Finland, France, German Democratic Republic, German Federal Republic, Greece, Hungary, Italy, Luxembourg, Netherlands, Norway, Poland, Rumania, Spain, Sweden, Switzerland, USSR and Yugoslavia). Its status is uncertain in Belgium, Portugal and European Turkey. It has disappeared from some localities in Britain but has been recently recorded at several others. It never occurred naturally in Iceland. Ireland is the only European country in which it once occurred but is now absent.     

Magnetic susceptibility changes in relation to pedogenesis in a Xeralf chronosequence in northwestern Spain

Pedogenesis under aerobic conditions is usually associated with an increase in magnetic susceptibility (χ, mass‐specific), which results from the formation of nano‐sized magnetite and/or maghaemite. In this study, we systematically investigated the χ trend in Xeralfs from a chronosequence of 13 river terraces in an area with a Mediterranean climate in Spain. The soils in the younger terraces are well drained and reddened, but those of the older terraces exhibit redoximorphic features and reduced χ values, because of the presence of a perched water table. In the well‐drained members of the chronosequence, the frequency dependent magnetic susceptibility, χ_FD, which is a proxy for the concentration of nano‐sized pedogenic ferrimagnets such as maghaemite, was highly correlated with the concentration of haematite (Hm), but not with that of goethite (Gt). Also, the peak χ_FD increased with increasing age in the younger freely drained soils, indicating that no steady state had been reached, and decreased with increasing depth. The formation of maghaemite can be explained by either or both of two formation models, namely: (i) ferrihydrite → maghaemite → haematite solid state transformations; and (ii) the reaction of bacterially produced Fe(II) with an Fe hydroxide phase to form magnetite, which is later oxidized to maghaemite. Comparison between these soils and those in other climatic regions indicates that the Hm/χ_FD ratio increases with increasing soil temperature and with the degree of weathering. In the horizons exhibiting redoximorphic features on the higher terraces, there was significantly less Hm and χ_FD in clay than in the well‐drained younger soils, possibly because of reductive dissolution of haematite and maghaemite. Laboratory experiments showed that susceptibility to reductive dissolution increased in the sequence goethite < maghaemite < haematite, which is consistent with the relative abundance of these minerals in the redoximorphic horizons.     

Sediment management options for the lower Ebro River and its delta

Background, Aim and Scope  Past and present management of the Ebro catchment have altered water, sediment and nutrient fluxes of the lower Ebro River and its delta. The construction of the Mequinensa and Riba-Roja dams during the 1960s disrupted the sediment transport continuity. As a result, the lower Ebro River and its delta are facing a reduction in sediment delivery which is estimated to be up to 99% of its original yield (about 3 × 10⁷ t/yr). Consequently, about 45% of the emerged delta will be under the mean sea level by 2100 due to subsidence and sea level rise, whereas the delta coast is retreating at a rate of several meters per year in the mouth area. This paper aims to establish the basis for a sediment management plan directed to offset the effects of the sediment delivery deficit of the Ebro delta. Main Features  A new management plan named ‘Integrated Plan for the Protection of the Ebro Delta’ (PIPDE) is being presently elaborated in order to develop sustainable management of the Ebro River and delta through an integrated management of water, sediment and habitats, in order to achieve European Union (EU) Water Framework Directive (WFD) requirements. Among other aspects, the plan aims to restore the sediment flux of the lower Ebro River by means of both the removal of the sediment trapped behind the dams and the transport of the sediment downstream of the reservoirs to the river mouth and delta plain. Results  Preliminary studies show that the ‘flushing flood’ method has lower costs and is the most adapted method to transfer the sediments retained into the Riba-Roja dam. The required sediment load to stop coastal retreat in the mouth area and to compensate relative sea level rise represents 10 times the present suspended load (0.021 g/l), but is 10 times lower than the total volume of sediment delivered to the sea under natural conditions. Sediment delivery to the delta plain can be accomplished through the rice irrigation system, a method used prior to dam construction. Discussion  Problems of achieving a sustainable management of water and sediment are mostly linked to reservoir management. Technical problems associated with by-passing sediments through the reservoirs can be solved through operational and structural changes. Benefits of sediment flow recovery are multiple, including maintenance of the reservoir capacity, possible decline of invasive species, reduction of elevation loss and coastal retreat in the delta. Conclusions  The partial restoration of sediment fluxes in the lower Ebro River and its delta is technically feasible and environmentally desirable, but further detailed studies need to be carried out before the plan can be implemented. Perspectives  Overall, the sustainability of the lower Ebro River and delta can only be guaranteed by the implementation of a new reservoir management concept where the ecological and morphological values, as well as the economical and social values, have to be taken into consideration.