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37 p. -- Bibliogr.: p. 33-37, Egungo glaziarren eremuaren %4-7 inguru higakinez estalitako glaziarrek hartzen dute, eta hauen kopuruan eta azaleran hazkunde nabaria ematea espero da datozen hamarkadetan. Glaziar mota hauek urtze eremuan higakinen geruza jarraia aurkezten dutenak dira, eta presentzia esanguratsua dute Pirinioetako glaziarretan, egungo 21 glaziarretatik 14tan agertuta. Helburu nagusi bezala, egoera honetara iristeko prozesua aztertu da, mende honetako lehen 20 urteetan emandako bilakaera ikertuz, eta higakinen ekarpena areagotzeko joera antzeman da hemen ere, glaziarren azaleraren atzera-egite orokorrarekin batera. Urte ezberdinetako satelite-irudiak erabilita, eta 2000. eta 2020. urteetan burututako inbentarioetan oinarrituta, glaziarren azaleraren galera neurtu da lehenik. Estalki hauen inguruan esan dezakegu duela 20 urte dagoeneko agertzen ziren kasuetan nabarmenki hazi direla, eta beste zenbait kasutan estalkirik ez izatetik partzialki estalita egotera pasa direla. Higakinez estalitako glaziarren artean estalki hauek azaleraren %4,2 hartzetik %18,1 hartzera pasa dira. Gainera, eta bigarren xede gisa, higakin-estalkien agerpena glaziarren azaleraren galerarekin erlazioan jarri da, eta glaziar handi nagusietan oinarritu gara ikerketa hau aurrera eramateko; besteak beste, Aneto, Ossoue, Maladeta edo Monte Perdidoko glaziarretan, nahiz eta kasu guztiak aztertu diren dinamika ezberdinak kontuan hartuz. Joera orokor batean, higakin-estalkia aurkezten duten glaziar horietan azaleraren galera txikiagoa eman da eta glaziar “txurietan”, berriz, galera deigarrienak, estalki hauek babes moduko bat ematen dutela antzeman dugularik. Baina badira beste zenbait faktore aintzat edukitzekoak, horregatik glaziar hauek hartzen dituzten mazizoen ezaugarri ezberdinak aipatzen dira, higakinen ekarpena baldintzatzen dutenak, baita glaziarrei ematen dizkieten beste babes motak ere. Oro har, material sedimentario eta metamorfikoz osatutako mazizoen kasuan higakinen ekarpena errazten dela esan dezakegu

[EN]Pyrenean glaciers are the largest in southern Europe. Their survival is threatened by climate change, highlighting the significance of their study. This research presents an assessment of changes in the glacierized area and thickness of Pyrenean glaciers from 2011 to 2020, using high-resolution optical satellite, airborne lidar and UAV images. The total glacierized area has shrunk by 23.2% and thickness has decreased on average by 6.3 m. These two variables show no correlation for individual glaciers. Although climatic conditions do not vary much among glaciers, their evolution was heterogeneous during the study period. The smaller glaciers (<10 ha) show a higher variability in their area decrease and thickness loss whereas the four largest glaciers (>10 ha) have a more homogeneous response. This can be attributed to the generally larger influence of local topography on the response of the smaller Pyrenean glaciers. There is no sign of slowdown in glacier shrinkage respect to previous decades.

[EN]Unmanned Aerial Vehicles (UAVs) offer great flexibility in acquiring images in inaccessible study areas, which are then processed with stereo-matching techniques through Structure-from-Motion (SfM) algorithms. This procedure allows generating high spatial resolution 3D point clouds. The high accuracy of these 3D models allows the production of detailed snow depth distribution maps through the comparison of point clouds from different dates. In this way, UAVs allow monitoring of remote areas that were not achievable previously. The large number of works evaluating this novel technique has not, to date, conducted a systematic evaluation of concurrent snowpack observations with different UAV devices. Taking into account this, and also bearing in mind that potential users of this technique may be interested in exploiting ready-to-use commercial devices, we conducted an evaluation of the snow depth distribution maps with different commercial UAVs. During the 2018-19 snow season, two multi-rotors (Parrot Anafi and DJI Mavic Pro2) and one fixed-wing device (SenseFly eBee plus) were used on three different dates over a small test area (5 ha) within Izas Experimental Catchment in the Central Pyrenees. Simultaneously, snowpack distribution was retrieved with a Terrestrial Laser Scanner (TLS, RIEGL LPM-321) and was considered as ground truth. Three different georeferencing methods (Ground Control Points, ICP algorithm over snow-free areas and RTK-GPS positioning) were tested, showing equivalent performances under optimum illumination conditions. Additionally, for the three acquisition dates, both multi-rotors were flown at two distinct altitudes (50 and 75 m) to evaluate impact on the obtained snow depth maps. The evaluation with the TLS showed an equivalent performance of the two multi-rotors, with mean RMSE below 0.23 m and maximum volume deviations of less than 5%. Flying altitudes did not show significant differences in the obtained maps. These results were obtained un

The 2030 Agenda includes objectives in three dimensions (economic, social and environmental). To these three, we must add the territory where the action plans are implemented. Hence, as researchers working in hydrology we must generate knowledge towards the resilience of dynamic territories combining Water and Land. Thus, this article analyses the need to establish a basin-perspective in water management instead of the usual river-perspective, considering the basin as the basic bio-physical unit for territorial planning. Climate change mitigation and adaptation policies converge in the basin, facilitating the identification of synergies and trade-offs between both strategies. In fact, global mitigation policies focus, largely, on carbon sequestration through reforestation, neglecting its side-effects on adaptation. The hydrological functions of the territory affect the quantity, quality, location and timing of water, by accumulating, moving and transforming it. Therefore, accepting this water regulatory function would imply a change in the way of understanding the management of water resources and an improvement in the integration of hydrological services in the territorial planning. For this purpose, local knowledge and knowledge on trade-offs and synergies between different objectives are needed. In this era of uncertainties, we should focus our main research strategies towards minimization of uncertainties in order to properly manage them and make knowledge-informed decisions, thus, changing the management paradigm. We need, therefore, socio-political will to redirect territorial dynamics, incorporating a development model adapted to local ecosystem services limitations, placing Land and Water in the centre of the territory, anywhere in the world; Garapen Iraunkorrerako 2030 Agendaren hiru dimentsioei (ekonomikoa, soziala eta ingurumenarena) lurraldearena gehitu behar zaie, ekintza-planak gauzatzeko ezinbesteko ingurune fisikoa baita. Hortik dator hidrologiatik a

This paper presents a new geomorphological map for the lower Hushe Valley (below 3400 m asl), located to the SE of the Central Karakoram in Baltistan (North Pakistan). Fieldwork and remote sensing were combined to improve understanding of the most recent surface landforms to produce a 1:50,000 scale map. Thirteen landform types associated with glacial, fluvial, gravitational and mass wasting processes were identified and mapped. Particular emphasis was made on currently dynamic processes that could pose a threat to the population. The distribution of the landforms on the valley (reworked tills, alluvial fans, rockfalls, among others) differs between the eastern and the western hillslopes, and from north to south, mainly due to bedrock types, location of geological structures and distribution of lateral tributaries. This map is the first and necessary step towards a deep assessment on geological risk related to external processes in the area.

Inferences of the interactions between species' ecological niches and spatial distribution have been historically based on simple metrics such as low-resolution dietary breadth and range size, which might have impeded the identification of meaningful links between niche features and spatial patterns. We analysed the relationship between dietary niche breadth and spatial distribution features of European bats, by combining continent-wide DNA metabarcoding of faecal samples with species distribution modelling. Our results show that while range size is not correlated with dietary features of bats, the homogeneity of the spatial distribution of species exhibits a strong correlation with dietary breadth. We also found that dietary breadth is correlated with bats' hunting flexibility. However, these two patterns only stand when the phylogenetic relations between prey are accounted for when measuring dietary breadth. Our results suggest that the capacity to exploit different prey types enables species to thrive in more distinct environments and therefore exhibit more homogeneous distributions within their ranges. Ecological niche breadth may help explain spatial distribution patterns in animals. In this study on European bats, Alberdi et al. combine DNA metabarcoding and species distribution modelling to show that dietary niche breadth is related to hunting flexibility and broad-scale spatial patterns in species distribution.