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Plants regulate soils and microclimate, provide substrate for heterotrophic taxa, are easy to observe and identify and have a stable taxonomy, which strongly justifies the use of plants as bioindicators in monitoring and conservation. However, insects and fungi make up the vast majority of species. Surprisingly, it remains untested whether plants are strong predictors of total multi-taxon species richness. To answer this question, we collected an extensive data set on species richness of vascular plants, bryophytes, macrofungi, lichens, plant-galling arthropods, gastropods, spiders, carabid beetles, hoverflies and OTU richness from environmental DNA metabarcoding. Plant species richness per se was a moderate predictor of richness of other taxa. Taking an ecospace approach to modelling, the addition of plant-derived bioindicators revealed 1) a consistently positive effect of plant richness on other taxa, 2) prediction of 12-55% of variation in other taxa and 48 % of variation in the total species richness.

IntroductionA paper by Rorsch, Frello, Soper, and de Lange in the Journal of Information Ethics (Spring 2005) discusses why the postulates of the Danish skeptical environmentalist Bjorn Lomborg have been opposed from the beginning by experts in the various fields dealt with by Lomborg. They conclude falsely that the experts act as a social group, using their authority to suppress Lomborg. This is a cunning statement, because if any group of experts protests, the protest will be seen as a confirmation of the statement. Instead, I will here do the tire-some but necessary job of demonstrating in detail that the claims in their paper are totally wrong.The Lomborg CaseBjorn Lomborg first published his controversial anti-environmentalist points of view in a major Danish newspaper at the start of i998; then, in the autumn of i998, in a Danish booki; and later, in the autumn of 200i, an English version of the book,2 The Skeptical Environmentalist (hereafter TSE). Editions have since been published in many other languages.The article and books ignited a fierce and continuing debate. There have been several attempts in scientific forums to clarify Lomborg's controversial claims. In all of these, Lomborg has had ample opportunity to defend his views. However, not a trace of consensus has been reached, because Lomborg has practically never made any admissions, even of obvious errors. The clarification attempts were the following:1. In May i999, a group of Danes produced a book refuting Lomborg's claims,3 and Lomborg published a response on the internet.4 A public debate was arranged.2. The same group of Danes produced an English version of the "counterbook," which appeared in June 2002.53. The January 2002 issue of Scientific American was devoted to extensive criticism of TSE.6 Lomborg's response was a 32 page rebuttal,7 which was followed by a 2i page reply by J. Holdren and the editor of Scientific American, J. Rennie.84. Complaints were lodged with the Danish Committee for Scientific Dishonesty (abbreviated UVVU in Danish). The first complaint was lodged by me in February 2002, and was soon followed by two others, viz., one by M. Hertz and H. Stiesdal (DK), and one by Stuart Pimm (USA) and Je∂ Harvey (NL). After nearly a year, in January 2003, UVVU announced its decision.9The 24 scientific members of UVVU, representing the social, natural and medical sciences, and the chairman, a high court judge, deemed Lomborg's book "objectively dishonest." By this they meant that what he wrote was, by an objective evaluation, not true, whether he was consciously aware of it or not. UVVU refrained from deciding whether Lomborg was "subjectively dishonest," i.e., whether his errors were deliberate.Lomborg appealed the decision of UVVU to the Danish Ministry of Research. In December 2003, the Ministry ruled that UVVU was not legally competent to judge on objective dishonesty, and it therefore annulled UVVU's verdict. Their competence, it was held, exclusively covered "subjective dishonesty," i.e., deliberate cheating, an issue on which, unfortunately, they had not pronounced. Further details can be read in my account, "The Lomborg Story."i0Provocative or untrue?For the sake of simplicity, we may formulate two alternative hypotheses to explain the opposition of most scientists to Lomborg's postulates.a. When Lomborg claims that many experts have exaggerated the severity of environmental problems, the experts are unable to refute this; instead, they persecute him with accusations of ignorance and with ad hominem attacks. They do not understand his approach and they defend their fields against the intruder who crosses professional boundaries. This hypothesis that Lomborg stands as a brave young man opposing the old-fashioned inquisition may be called the "Galileo hypothesis," because some Lomborg supporters have compared him to Galileo.b. Lomborg's postulates are deliberately manipulated, and may be refuted. …

All-hybrid populations of the water frog, Rana esculenta, are exceptional in consisting of independently and to some extent sexually reproducing interspecific hybrids. In most of its range R. esculenta reproduces hemiclonally with one of the parental species, R. lessonae or R. ridibunda, but viable populations of diploid and triploid hybrids, in which no individuals of the parental species have been found, exist in the northern part of the range. We test the hypothesis that nonhybrids arise every year in these all-hybrid populations, but die during larval development. Microsatellite markers were used to determine the genotypes of adults and abnormal and healthy offspring in three all-hybrid populations of R. esculenta in Denmark. Of all eggs and larvae, 63% developed abnormally or died, with some being nonhybrid (genomes matching one of the parental species), many being aneuploid (with noninteger chromosome sets), a few being tetraploid, and many eggs possibly being unfertilized. The 37% surviving and apparently healthy froglets were all diploid or triploid hybrids. In all three populations, gametogenesis matched the pattern previously described for all-hybrid R. esculenta populations in which most triploid adults have two R. lessonae genomes. This pattern was surprising for the one population in which triploid adults had two R. ridibunda genomes, because here it leads to a deficiency of gametes with an R. lessonae genome and should compromise the stability of this population. We conclude that faulty gametogenesis and mating between frogs with incompatible gametes induce a significant hybrid load in all-hybrid populations of R. esculenta, and we discuss compensating advantages and potential evolutionary trajectories to reduce this hybrid load.

All-hybrid populations of the water frog, Rana esculenta, are exceptional in consisting of independently and to some extent sexually reproducing interspecific hybrids. In most of its range R. esculenta reproduces hemiclonally with one of the parental species, R. lessonae or R. ridibunda, but viable populations of diploid and triploid hybrids, in which no individuals of the parental species have been found, exist in the northern part of the range. We test the hypothesis that nonhybrids arise every year in these all-hybrid populations, but die during larval development. Microsatellite markers were used to determine the genotypes of adults and abnormal and healthy offspring in three all-hybrid populations of R. esculenta in Denmark. Of all eggs and larvae, 63% developed abnormally or died, with some being nonhybrid (genomes matching one of the parental species), many being aneuploid (with noninteger chromosome sets), a few being tetraploid, and many eggs possibly being unfertilized. The 37% surviving and apparently healthy froglets were all diploid or triploid hybrids. In all three populations, gametogenesis matched the pattern previously described for all-hybrid R. esculenta populations in which most triploid adults have two R. lessonae genomes. This pattern was surprising for the one population in which triploid adults had two R. ridibunda genomes, because here it leads to a deficiency of gametes with an R. lessonae genome and should compromise the stability of this population. We conclude that faulty gametogenesis and mating between frogs with incompatible gametes induce a significant hybrid load in all-hybrid populations of R. esculenta, and we discuss compensating advantages and potential evolutionary trajectories to reduce this hybrid load.

Summary (1) N added to decomposing organic matter often has no effect or a negative effect on microbial activity, at least in the long term. More than 60 papers are cited in support of this statement. (2) The negative effect of N is mainly found with recalcitrant organic matter with a high C/N ratio (straw, wood, etc.), whereas a positive effect of N is common for easily degradable organic material with low C/N ratio. (3) The negative effect of N could be explained by: (i) N disturbs the outcome of competition between potent and less potent decomposers; (ii) through ‘ammonia metabolite repression’, N blocks production of certain enzymes, at least in basidiomycetes, and enhances breakdown of the most available cellulose, whereby recalcitrant lignocellulose accumulates; (iii) amino compounds condense with polyphenols and other decomposition products, forming ‘browning precursors’ which are toxic or inhibitory. (4) The effect of adding N may depend on the microflora present. (5) There are indications that some microorganisms have a ‘luxury uptake’ of N when it is present in sufficient amounts, thereby delaying N mineralization. (6) The addition of N seems to increase the formation of water-soluble, brown, recalcitrant compounds, but to decrease the amount of humus formed.

A genetic study of the European tree frog, Hyla arborea, in Denmark was undertaken to examine the population structure on mainland Jutland and the island of Lolland after a period of reduction in suitable habitat and population sizes. The two regions have experienced the same rate of habitat loss but fragmentation has been more severe on Lolland. Genetic variation based on 12 polymorphic DNA microsatellites was analysed in 494 tree frogs sampled from two ponds in Jutland and 10 ponds on Lolland. A significant overall deviation from Hardy-Weinberg expectations could be attributed to three ponds, all on Lolland. This was most probably caused by an inbreeding effect reducing fitness, which was supported by the observed significant negative correlation between larva survival and mean F(IS) value and mean individual inbreeding coefficient. A significant reduction in genetic variation (bottleneck) was detected in most of the ponds on Lolland. Population-structure analysis suggested the existence of at least 11 genetically different populations, corresponding to most of the sampled population units. The results indicated that the populations were unique genetic units and could be used to illustrate the migration pattern between newly established ponds arisen either by natural colonization of tree frogs or by artificial introduction. A high degree of pond fidelity in the tree frogs was suggested. A severe fragmentation process reducing population size and fitness within some of the populations probably caused the significant reduction in genetic variation of tree frog populations on Lolland.