01570nas a2200217   4500008004100000245008700041210006900128260001200197300001200209490000700221520087200228653001101100653002801111653001001139653001101149653001301160653002901173100001401202700002001216856011601236       1996                        eng d00aThe effect of increased water level on Isoetes lacustris L. in Lake Baciver, Spain0 aeffect of increased water level on Isoetes lacustris L in Lake B  c1996///  a57 - 590 v343 aTen months after flooding lake Baciver, water levels were 5.5 m higher than the previous normal and the area formally occupied by the Isoetes population was reduced. All Isoetes originally present below 0.6 m died, and only plants standing between 5.8 and 6.1 m (new depth) survived. As irradiance decreased, remaining individuals produced fewer leaves, but their biomass production was higher, as leaf length increased in response to the diminished available irradiance. Because leaf mortality was excessive, regeneration capacity, population performance and dynamics were adversely affected. In 1992, no new production occurred in Isoetes lacustris individuals surviving after the winter. We suggest that low surface oxygen levels at the water column under the ice, and total anoxia below 6 m depth, caused the demise of the I. lacustris population in Lake Baciver.10aAnoxia10aLeaf primary production10aLight10aOxygen10aPyrenees10aWater level fluctuations1 aGacia, E.1 aBallesteros, E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0030188498&partnerID=40&md5=76a5af33fa658c06abddf82d836c45a500547nas a2200133   4500008004100000245012200041210006900163260001200232300001200244490000700256100001400263700002000277856011600297       1994                        eng d00aProduction of Isoetes lacustris in a Pyrenean lake: Seasonality and ecological factors involved in the growing period0 aProduction of Isoetes lacustris in a Pyrenean lake Seasonality a  c1994///  a77 - 890 v481 aGacia, E.1 aBallesteros, E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0028159936&partnerID=40&md5=efc7c11d4bd991282dc11c61e9b0a50701537nas a2200145   4500008004100000245009600041210006900137260001200206300001200218490000700230520100400237100001401241700002001255856011601275       1993                        eng d00aPopulation and individual variability of Isoetes lacustris L. with depth in a Pyrenean lake0 aPopulation and individual variability of Isoetes lacustris L wit  c1993///  a35 - 470 v463 aStructural (density and biomass), morphological and phenological characteristics of a population of Isoetes lacustris L. in a high mountain lake in the Pyrenees were studied. Changes in these parameters along a depth gradient can be used to distinguish a shallow water population (0.3-1.3 m depth) from a deep water population (1.8-2.3 m depth). Density of individuals decreased with depth, while biomass, size, size diversity and fertility showed the opposite pattern. The effect of ice-scour during winter together with a lower organic matter content in shallow areas are suggested as the main ecological factors responsible for these differences. Extremely high biomass values, when compared with North European populations of I. lacustris, seem to be related to a higher light availability in Pyrenean lakes. High rates of sedimentation causing burying of individuals and light depletion can explain the sharp, shallow lower boundary of the distribution of I. lacustris in Lake Baciver. © 1993.1 aGacia, E.1 aBallesteros, E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0027878362&partnerID=40&md5=9b9a525ee71441485f2320e50af1ec17