Both climate and land-use changes,including the introduction and spread of allochthonous species,are forecast to affect forest ecosystems.Accordingly,forests will be affected in terms of species composition as well as...Both climate and land-use changes,including the introduction and spread of allochthonous species,are forecast to affect forest ecosystems.Accordingly,forests will be affected in terms of species composition as well as their soil chemical and biological characteristics.The possible changes in both tree cover and soil system might impact the amount of carbon that is stored in living plants and dead biomass and within the soil itself.Additionally,such alterations can have a strong impact on the detrital food web that is linked to litter decomposition.Although there are studies on the infuence of plant diversity on soil physical and chemical characteristics,the effects on soil biological activity and carbon storage processes remain largely unknown.The aim of this study was to investigate and compare chemical and biological variables in covariation with plant communities in an autochthonous beech forest(Fagus sylvatica L.)and a black pine plantation(Pinus nigra J.F.Arnold subsp.nigra).Our results confirmed that the two communities were considerably different,with the old-growth beech community having a lower number of plant species and the pine community was in development as a consequence of anthropogenic activities.These aspects of the two communities were also refected in the soil,with the beech soil having higher nitrogen levels and a more specialized microbial community compared to the pine soil,with most extracellular enzymes(such as peroxidase and chitinase)showing lower activity in the pine soil.展开更多
The red snapper Lutjanus campechanus (Poey, 1860) has a high commercial value that sustains an important fishery in Mexico. In this study, the patterns in morphological variations from early juvenile to adult stages w...The red snapper Lutjanus campechanus (Poey, 1860) has a high commercial value that sustains an important fishery in Mexico. In this study, the patterns in morphological variations from early juvenile to adult stages were assessed by geometric methods (GM) in 194 organisms. Changes in shape were more evident and rapid in the early juvenile stage and decreased during adulthood. The principal components analysis of shape (Relative Warp Analysis, or RWA) identified size and body depth as the main sources of variance associated to both juvenile and adult organisms. The outline of the head and the tail showed the most noticeable differences following the ontogenic pathway visualized by thin-plate splines indicating that the ontogenetic pathway of the upper half and the lower half of the dorsal head profile (DHP) are in relatively opposite directions than those from the tail that bends ventrally. The Two-Block Partial Least Square analysis (2B-PLS) and their CR coefficients showed that the two modules had a moderate linear trend (p = 0.001). Although the blocks have morphological changes at different rates, there is a moderate synchrony in growth by modules. This study is the first to report the use of geometrical morphometry in L. campechanus in Mexico.展开更多
基金funding provided by Universitàdegli Studi della Campania Luigi Vanvitelli within the CRUI-CARE Agreement。
文摘Both climate and land-use changes,including the introduction and spread of allochthonous species,are forecast to affect forest ecosystems.Accordingly,forests will be affected in terms of species composition as well as their soil chemical and biological characteristics.The possible changes in both tree cover and soil system might impact the amount of carbon that is stored in living plants and dead biomass and within the soil itself.Additionally,such alterations can have a strong impact on the detrital food web that is linked to litter decomposition.Although there are studies on the infuence of plant diversity on soil physical and chemical characteristics,the effects on soil biological activity and carbon storage processes remain largely unknown.The aim of this study was to investigate and compare chemical and biological variables in covariation with plant communities in an autochthonous beech forest(Fagus sylvatica L.)and a black pine plantation(Pinus nigra J.F.Arnold subsp.nigra).Our results confirmed that the two communities were considerably different,with the old-growth beech community having a lower number of plant species and the pine community was in development as a consequence of anthropogenic activities.These aspects of the two communities were also refected in the soil,with the beech soil having higher nitrogen levels and a more specialized microbial community compared to the pine soil,with most extracellular enzymes(such as peroxidase and chitinase)showing lower activity in the pine soil.
文摘The red snapper Lutjanus campechanus (Poey, 1860) has a high commercial value that sustains an important fishery in Mexico. In this study, the patterns in morphological variations from early juvenile to adult stages were assessed by geometric methods (GM) in 194 organisms. Changes in shape were more evident and rapid in the early juvenile stage and decreased during adulthood. The principal components analysis of shape (Relative Warp Analysis, or RWA) identified size and body depth as the main sources of variance associated to both juvenile and adult organisms. The outline of the head and the tail showed the most noticeable differences following the ontogenic pathway visualized by thin-plate splines indicating that the ontogenetic pathway of the upper half and the lower half of the dorsal head profile (DHP) are in relatively opposite directions than those from the tail that bends ventrally. The Two-Block Partial Least Square analysis (2B-PLS) and their CR coefficients showed that the two modules had a moderate linear trend (p = 0.001). Although the blocks have morphological changes at different rates, there is a moderate synchrony in growth by modules. This study is the first to report the use of geometrical morphometry in L. campechanus in Mexico.
