86 resultados para Tropical plant species


Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (non-flowering indviduals) and regenerative height (flowering individuals) in 2002 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2002, plant height was recorded twice a year: in late June and just before biomass harvest during peak standing biomass in late August. For 3 target plant individuals (if present) per sown species from the central area of the plots, vegetative height (non-flowering indviduals) and regenerative height (flowering individuals) were measured as stretched height. Provided are the indivdiual measurements and the mean over the measured plants per plot (in June) and the mean over the measured plants per plot (in August).

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (heighest leaf) in 2004 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2004, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For plants at 3 random points in a control area at the margin of each experimental, vegetative height (heighest leaf) was measured as standing height (without stretching the plant). Provided are the individual measurements and the mean over the measured plants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (length of the main axis) in 2003 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2003, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For 30 target plant individuals harvested at 10 cm distances along a 5 m transect in a control area at the margin of each experimental plot, vegetative height (length of the main axis) was measured as the length of the main axis of the plant. Provided is the mean over the measured plants per plot.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Carbon dioxide (CO2) levels projected to occur in the oceans by the end of this century cause a range of behavioural effects in fish, but whether other highly active marine organisms, such as cephalopods, are similarly affected is unknown. We tested the effects of projected future CO2 levels (626 and 956 µatm) on the behaviour of male two-toned pygmy squid, Idiosepius pygmaeus. Exposure to elevated CO2 increased the number of active individuals by 19-25% and increased movement (number of line-crosses) by nearly 3 times compared to squid at present-day CO2. Squid vigilance and defensive behaviours were also altered by elevated CO2 with >80% of individuals choosing jet escape responses over defensive arm postures in response to a visual startle stimulus, compared with 50% choosing jet escape responses at control CO2. In addition, more escape responses were chosen over threat behaviours in body pattern displays at elevated CO2 and individuals were more than twice as likely to use ink as a defence strategy at 956 µatm CO2, compared with controls. Increased activity could lead to adverse effects on energy budgets as well as increasing visibility to predators. A tendency to respond to a stimulus with escape behaviours could increase survival, but may also be energetically costly and could potentially lead to more chases by predators compared with individuals that use defensive postures. These results demonstrate that projected future ocean acidification affects the behaviours of a tropical squid species.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Understanding species distribution patterns and the corresponding environmental determinants is a crucial step in the development of effective strategies for the conservation and management of plant communities and ecosystems. Therefore, a central prerequisite is the biogeographical and macroecological analysis of factors and processes that determine contemporary, potential, as well as future geographic distribution of species. This thesis has been conducted in the framework of the BIOMAPS-BIOTA project at the Nees Institute of Biodiversity of Plants, which was funded by the German Federal Ministry of Education and Research (BMBF). The study investigated patterns of plants species richness and phytogeographic regions under contemporary environmental conditions and forecasted future climate change in the area of West Africa covering five countries: Benin, Burkina Faso, Côte d'Ivoire, Ghana and Togo. Firstly, geographic patterns of vascular plant species richness have been depicted at a relatively fine spatial resolution based on the potential distribution of 3,393 species. Species richness is closely related to the steep climatic gradient existing in the region with a high concentration of species in the most humid areas in the south and decreases towards the northern drier areas. The investigation of the effectiveness of the existing network of protected areas shows an overall good coverage of species in the study area. However, the proportion of covered species is considerably lower at national extent for some countries, thus calling for more protected areas in order to cover adequately a maximum number of plants species in these countries. Secondly, based on the potential distribution range of vascular plant species, seven phytogeographic regions have been delineated that broadly reflect the vegetation zones as defined by White (1983). However notable differences to the delineation of White (1983) occur at the margins of some regions. Corresponding to a general southward shifted of all regions. And expansion of the Sahel vegetation zone is observed in the north, while the rainforest zone is decreased in the very south.This is alarming since the rainforest shelters a high number of species and a high proportion of range-restricted or endemic species, despite their relatively small extent compared to the other regions. Finally, the evaluation of the potential impact of climate change on plant species richness in the study area, results in a severe loss of future suitable habitat for up to 50% of species per grid cell, particularly in the rainforest region. Moreover, the analysis of the possible shift of phytogeographic regions shows in general a strong deterioration of the West African rainforest. In contrast the drier areas are expanding continuously, although a slight gain in species number can be observed in some particular regions. The overall lesson to retain from the results of this study is that the West African rainforest should be fixed as a high priority area for the conservation of biodiversity of plants, since it is subject to severe contemporary and projected future threats.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (heighest leaf) and regenerative height (heighest flower) in 2007 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2007, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For target plant individuals at 10 points separated by 1 m each along a transect in the central area in the plots, vegetative height (heighest leaf) and regenerative height (heighest flower) were measured as standing height (without stretching the plant). In 2007, also the plots of the management experiment, that altered mowing frequency and fertilized subplots (see further details below) were sampled by measuring vegatation height five times, every 0.5m on a 3m transekt along the side of the management plots. Provided are the individual measurements and the mean over the measured plants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (heighest leaf) and regenerative height (heighest flower) in 2008 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2008, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For target plant individuals at 10 points separated by 1 m each along a transect in the central area in the plots, vegetative height (heighest leaf) and regenerative height (heighest flower) were measured as standing height (without stretching the plant). In 2008, also the plots of the management experiment, that altered mowing frequency and fertilized subplots (see further details below) were sampled by measuring vegatation height five times, every 1m on a 5m transekt along the side of the management plots. Provided are the individual measurements and the mean over the measured plants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (heighest leaf) and regenerative height (heighest flower) in 2005 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2005, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For target plant individuals at 10 points separated by 1 m each along a transect in the central area in the plots, vegetative height (heighest leaf) and regenerative height (heighest flower) were measured as standing height (without stretching the plant). Provided are the individual measurements and the mean over the measured plants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains measurements of plant height: vegetative height (heighest leaf) and regenerative height (heighest flower) in 2006 from the Main Experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the Main Experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown into the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, 4 functional groups). Plots were maintained by bi-annual weeding and mowing. In 2006, plant height was recorded twice a year just before biomass harvest (during peak standing biomass in late May and in late August). For target plant individuals at 10 points separated by 1 m each along a transect in the central area in the plots, vegetative height (heighest leaf) and regenerative height (heighest flower) were measured as standing height (without stretching the plant). In 2006, also the plots of the management experiment, that altered mowing frequency and fertilized subplots (see further details below) were sampled by measuring vegatation height five times, every 1m on a 5m transekt along the side of the management plots. Provided are the individual measurements and the mean over the measured plants.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set describes different vegetation, soil and plant functional traits (PFTs) of 15 plant species in 30 sampling plots of an agricultural landscape in the Haean-myun catchment in South Korea. We divided the data set into two main tables, the first one includes the PFTs data of the 15 studied plant species, and the second one includes the soil and vegetation characteristics of the 30 sampling plots. For a total of 150 individuals, we measures the maximum plant height (cm) and leaf size (cm**2), which means the leaf surface area for the aboveground compartment of each individual. For the belowground compartment, we measured root horizontal width, which is the maximum horizontal spread of the root, rooting length, which is the maximum rooting depth, root diameter, which is the average root diameter of a the whole root, specific root length (SRL), which is the root length divided by the root dry mass, and root/shoot ratio, which is the root dry mass divided by the shoot dry mass. At each of the 30 studied plots, we estimated three different variables describing the vegetation characteristics: vegetation cover (i.e. the percentage of ground covered by vegetation), species richness (i.e. the number of observed species) and root density (estimated using a 30 cm x 30 cm metallic frame divided into nine 10 cm x 10 cm grids placed on the soil profile), as we calculated the total number of roots that appear in each of the nine grids and then we converted it into percentage based on the root count, following. Moreover, in each plot we estimated six different soil variables: Bulk density (g/cm**3), clay % (i.e. percentage of clay), silt % (i.e. percentage of silt), soil aggregate stability, using mean weight diameter (MWD), penetration resistance (kg/cm**2), using pocket penetrometer and soil shear vane strength (kPa).

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set describes the distribution of a total of 90 plant species growing on field margins of an agricultural landscape in the Haean-myun catchment in South Korea. We conducted our survey between July and August 2011 in 100 sampling plots, covering the whole catchment. In each plot we measured three environmental variables: slope, width of the field margin, and management type (i.e. "managed" for field margins that had signs of management activities from the ongoing season such as cutting or spraying herbicides and "unmanaged" for field margins that had been left untouched in the season). For the botanical survey each plot was sampled using three subplots of one square meter per subplot; subplots were 4 m apart from each other. In each subplot, we estimated three different vegetation characteristics: vegetation cover (i.e. the percentage of ground covered by vegetation), species richness (i.e. the number of observed species) and species abundance (i.e. the number of observed individuals / species). We calculated the percentage of the non-farmed habitats by creating buffer zones of 100, 200, 300, 400 and 500 m radii around each plot using data provided by (Seo et al. 2014). Non-farmed habitats included field margins, fallows, forest, riparian areas, pasture and grassland.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Soil temperature (in °C) was determined using a frequency domain sensor probe (WET-2 Sensor, Delta-T Devices, Cambridge, United Kingdom) on 1st August 2013. The device was inserted from the top 6 cm deep (length of the prongs) into the soil. The average of three measurements on the same day was calculated. All data where measured in the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown in the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, or 4 functional groups). Plots were maintained by bi-annual weeding and mowing.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

Soil porosity is the fraction of total volume occupied by pores or voids measured at matric potential 0. To measure soil porosity, soil samples were taken from each plot using sample rings with an internal diameter of 57 mm and height of 40.5 mm (inner volume of Vs=100 cm3). The samples were placed on a sand bed box with water level set to allow saturation of the samples with water. After 48 h the samples were weighed (ms), oven dried at 105 °C and weighed again to determine the dry weight (md). We calculated soil porosity (n [%]) using the density of water (?w=1 g cm?3), n=100 ? (mw-md) / (?w?Vs). To account for the spatial variation of soil properties, three replicates were taken per plot, approximately 2, 3 and 4 weeks after the flood that occurred at the field site during June 2013. Data are the average soil porosity values per plot. All data where measured in the main experiment plots of a large grassland biodiversity experiment (the Jena Experiment; see further details below). In the main experiment, 82 grassland plots of 20 x 20 m were established from a pool of 60 species belonging to four functional groups (grasses, legumes, tall and small herbs). In May 2002, varying numbers of plant species from this species pool were sown in the plots to create a gradient of plant species richness (1, 2, 4, 8, 16 and 60 species) and functional richness (1, 2, 3, or 4 functional groups). Plots were maintained by bi-annual weeding and mowing.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains aboveground plant biomass in 2003 (Sown plant community, Weed plant community, and Dead plant material; all measured in biomass as dry weight) of the monoculture plots of a large grassland biodiversity experiment (the Jena Experiment). In the monoculture plots the biomass of the sown plant community contains only a single species per plot and this species is a different one for each plot. Which species has been sown in which plot is stated in the plot information table for monocultures (see further details below). The monoculture plots of 3.5 x 3.5 m were established for all of the 60 plant species of the Jena Experiment species pool with two replicates per species. These 60 species comprising the species pool of the Jena Experiment belong to four functional groups (grasses, legumes, tall and small herbs). Plots were sown in May 2002 and are since maintained by bi-annual weeding and mowing. Aboveground plant biomass was harvested twice in 2003 just prior to mowing (during peak standing biomass in early June and in late August) on all experimental plots of the monocultures. This was done by clipping the vegetation at 3 cm above ground in 2 rectangles of 0.2 x 0.5 m per plot. The location of these rectangles was assigned prior to each harvest by random selection of coordinates within the core area of the plots (i.e. excluding an outer edge of 0.5 m). The positions of the rectangles within plots were identical for all plots. The harvested biomass was sorted into categories: sown plant species, weed plant species (species not sown at the particular plot), and detached dead plant material (i.e., dead plant material in the data file). All biomass was dried to constant weight (70°C, >= 48 h) and weighed. The data for individual subsamples (i.e. rectangles) and the mean over samples for all biomass measures are given.

Relevância:

90.00% 90.00%

Publicador:

Resumo:

This data set contains aboveground plant biomass in 2010 (Sown plant community, Weed plant community, Dead plant material, and Unidentified plant material; all measured in biomass as dry weight) of the monoculture plots of a large grassland biodiversity experiment (the Jena Experiment). In the monoculture plots the biomass of the sown plant community contains only a single species per plot and this species is a different one for each plot. Which species has been sown in which plot is stated in the plot information table for monocultures (see further details below). The monoculture plots of 3.5 x 3.5 m were established for all of the 60 plant species of the Jena Experiment species pool with two replicates per species. One of the replicate plots per species was given up after the vegetation period of 2007 for all but the nine species belonging also to the so called dominance experiment in Jena. These nine species are: Alopecurus pratensis, Anthriscus sylvestris, Arrhenatherum elatius, Dactylis glomerata, Geranium pratense, Poa trivialis, Phleum pratense, Trifolium repens and Trifolium pratense.In 2010 plot size was reduced to 1 x 1 m. These 60 species comprising the species pool of the Jena Experiment belong to four functional groups (grasses, legumes, tall and small herbs). Plots were sown in May 2002 and are since maintained by bi-annual weeding and mowing. Aboveground plant biomass was harvested twice in 2010 just prior to mowing (during peak standing biomass in early June and in late August) on all experimental plots of the monocultures. This was done by clipping the vegetation at 3 cm above ground in 1 rectangle of 0.2 x 0.5 m per plot. The location of this rectangle was in the center of the plot area. The positions of the rectangles within plots were identical for all plots. The harvested biomass was sorted into categories: sown plant species, weed plant species (species not sown at the particular plot), detached dead plant material (i.e., dead plant material in the data file), and remaining plant material that could not be assigned to any category (i.e., unidentified plant material in the data file). All biomass was dried to constant weight (70°C, >= 48 h) and weighed.