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The new Dutch forest monitoring network is a policy-guided, multiple-use, GIS-oriented forest monitoring network. It is designed to provide the Dutch government, on a cyclic 8-year basis, with actual information about Dutch forests. Variables that reflect the information needs of policy makers and interest groups were selected by means of interviews and workshops. High-ranking variables are: wood stock, ownership, stand age, management status, biodiversity, carbon stock, and recreational use. These and other variables are being measured in 3622 forest sites, selected according to an unaligned systematic sampling design. The data are stored in an ORACLE data base, made accessible through the internet. The Dutch forest area approximates a total of 360 000 ha; 46% is owned by private owners and organisations for nature conservation. Coniferous forests dominate (60%). Most forests were planted in 1940-1980. The total above ground volume of living trunk wood amounts to 56.3 million m3. The most common tree species are Quercus robur, Pinus sylvestris, and Betula pendula, the most common shrubs are Sorbus aucuparia, Prunus serotina, and Rhamnus frangula; while the most common other plant species are Deschampsia flexuosa, Rubus fruticosus s.l., and Dryopteris dilatata.
We offer a new framework for cellular automata modeling to describe and predict vegetation dynamics. The model can simulate community composition and spatial patterns by following a set of probabilistic rules generated from empirical data on plant neighborhood dynamics. Based on published data (Lippe et al. 1985), we apply the model to simulate Atlantic Heathland vegetation dynamics and compare the outcome with previous models described for the same site. Our results indicate reasonable agreement between simulated and real data and with previous models based on Markov chains or on mechanistic spatial simulation, and that spatial models may detect similar species dynamics given by non-spatial models. We found evidence that a directional vegetation dynamics may not correspond to a monotonic increase in community spatial organization. The model framework may as well be applied to other systems.
In plants plenty of inducible defense-related proteins classified into 17 pathogenesis-related (PR) families have been described. Expression of homologous PR genes from the same family can be induced by the different defense hormones, like salicylic acid (SA), jasmonic acid (JA) or ethylene (ET), and are also regulated in a organ- or tissue-specific manner. A recently identified pathogenesis-related gene family, the PRLIP (pathogenesis-related lipase) has 9 members in Arabidopsis and their organization and expression pattern — as it is summarized in this study — is similar to the one of genes coding for other PR proteins. PRLIP3, PRLIP8 and PRLIP9 showed a relatively high expression in all tissues tested with a maximum in root (PRLIP3), stem (PRLIP8) or siliques (PRLIP9). The activity of PRLIP3 gene was further induced by SA and JA treatment. Other members (PRLIP1, PRLIP2, PRLIP4 and PRLIP6), however, were detected only in some of the tested organs. High levels of PRLIP1 mRNA occurred in all green tissues and in siliques, while in the latter PRLIP2 also displayed high expression. PRLIP6 and PRLIP4 exhibited root specific transcription while no mRNAs of PRLIP5 and PRLIP7 were detected in any plant tissues examined. In leaves SA treatment enhanced PRLIP1 and PRLIP2 expression, JA treatment induced PRLIP6 and ET treatment upregulated both PRLIP1 and PRLIP6. This organization and expression diversity of the PRLIP gene family is typical to plant PR genes suggesting the encoded proteins might serve essential functions in plant defense or priming.
Within the frame of the Deppea two types of floral organisation have been recognised: the classic genus based on the type D. erythrorhiza Cham. et Schltdl., characterised by rotate corolla with very short tube, longer filaments and long linear anthers both longer than the corolla tube. The other floral type is characterised by funnel-form corolla, with longer upwards broadening corolla tube with short or absent filaments and short, ovate anthers. This corolla type was recognised by Standley (1933) and described as Edithea based on E. floribunda Standl. Based on seemingly intermediate corolla forms the two genera were united by the classic taxonomic treatment of Lorence and Dwyer (1988), but micromorphological-anatomical evidence (Borhidi et al. 2004) reinforced Standley’s concept, supported also by the molecular studies of Stranczinger et al. (2010). These latter ones claimed the attention to another taxonomic split existing within the generic frame of Deppea s. str. The separating evidences are in the fruit morphology. The great majority — including the type of the genus has subglobose or obovate to broadly elliptical hypanthium and fruit, ± as broad as long, smooth or 2 to 8-costate, and obovate placenta and loculicidal dehiscence. In contrast, five species have cylindrical or oblong to linear-oblong hypanthium and fruit 2 to 4 times as long as broad, with 8 densely disposed longitudinal nerves, oblong to linear-oblong placenta and apical to septicidal dehiscence. Molecular evidence grouped these species into a separate clade placed from the vicinity of Deppea species next to Hoffmannia. Therefore we consider this species-group as a new genus named Deppeopsis with the following description, and selecting Deppea hernandezii Lorence as the type of the new genus.
Extracts from some fern species have been found to be useful in fortifying livestock and fish feeds to enhance production especially in peasant communities. The chemical composition of Ceratopteris cornuta has not been documented in Nigeria. This study was thus designed to determine its suitability for use in fortifying fish feed by analysing the nutrient and anti-nutrient contents of its dimorphic fronds separately. One kg of sterile and fertile fronds of C. cornuta were collected, washed using distilled water and oven dried at 40 °C for about 96 hours. The dried samples were milled and analysed for proximate minerals, cyanide and oxalate analyses in triplicates. Results of the nutrient and anti-nutrient analyses show that both the sterile and the fertile fronds of C. cornuta can be used in aquaculture. The crude protein (4.22–5.28 g/100 g), moisture (87–91.00 g/100 g), carbohydrate (3.12–7.40 g/100 g), magnesium (23.55–194.65 mg/100 g), calcium (0.03 mg/100 g), potassium (0.17 mg/100 g), sodium (0.17 mg/100 g), silver (50.0 mg/100 g), cobalt (3.75–4.45 mg/100 g), lead (53.5–172.5 mg/100 g), copper (60.45–61.0 mg/100 g), manganese (15.65 mg/100 g), arsenium (50 mg/100 g), cadmium (3.75–4.50 mg/100 g), iron (430.00–537.45 mg/100 g) and selenium (106.83–195.45 mg/100 g) contents are considerably high. The anti-nutritional oxalate (0.86–1.38 mg/100 g) and cyanide (0.88–1.16 mg/100 g) are low and fall within the safe and acceptable limits as recommended by the World Health Organisation. Thus, extract from these fronds can be incorporated into livestocks and fish meals.
The phylogenetic relationship among species may influence the mechanisms controlling local community assembly in ecological time. We analyzed the degree of recurrence of phylogenetic structure patterns in woody plant communities distributed along grassland-forest ecotones, across different vegetation types in southern Brazil, and the effect of phylogenetic pool size used to assess such patterns. Species frequency in quadrats distributed along grassland-forest ecotones was surveyed in different phytogeographic regions, where forests tend to expand over grasslands. We used principal coordinates of phylogenetic structure (PCPS) to evaluate the structure within vegetation quadrats divided into three habitat categories: grassland, forest edge and forest interior. Furthermore, phylogenetic structure measures were computed using different phylogenetic pool sizes. Our analyses showed consistent patterns in relation to habitat categories and to different phylogenetic pool sizes. Basal clades of angiosperms were associated with forest areas, while late-divergence clades were associated with grasslands. These results suggest that grasslands act as phylogenetic habitat filters to forest woody species, independently of species composition at each site and the phylogenetic pool. Rosanae and Asteranae act as vanguards of forest expansion over grasslands, while Magnolianae species tend to be restricted to forest. Our results shed light on the organization of ecological systems, providing evidence of recurrent phylogenetic structure patterns in ecotone plant communities at regional scale.
The question addressed in this paper is whether plant traits and plant functional types related to forage selection by grazers are also related to those expressing short-term community response after grazing. Vegetation of natural campos grassland in south Brazil was examined for species composition and locally described for seven morphological traits before and after a controlled grazing period by bovine cattle. An optimization algorithm was used for the identification of plant functional effect types (PF ef T) and plant functional response types (PF ef T)-in this case, groups of plants similar in a given set of traits (assessed before and after one grazing short period, respectively) and in their association to grazing intensity. The results have shown that plant traits optimally defining plant types related to forage selection (PF ef Ts) were the same traits optimally defining short-term community response to grazing (PF re Ts); also similar trends of plant morphological variation were observed among populations before and after grazing, based on the traits’ correlation structure. However, at the community level the correlation vanished, since similar communities described by the performances of PF ef Ts were not as similar when described by PF re Ts. Hence, whether plant functional types related to forage selection (effect types) are also related to community response to grazing may depend on the level of organization considered. The paper advances on the operational definition of possible overlaps between effect and response plant functional types.
With continuing proliferation of human influences on landscapes, there is mounting incentive to undertake quantification of relationships between spatial patterns of human populations and vegetation. In considering such quantification, it is apparent that investigations must be conducted at different scales and in a comparative manner across regions. At the broader scales it becomes necessary to utilize remote sensing of vegetation for comparative studies against map referenced census data. This paper explores such an approach for the urbanized area in the Tokyo vicinity. Vegetation is represented by the normalized difference vegetation index (NDVI) as determined from data acquired by the thematic mapper (TM) sensor of the Landsat satellite. Sparseness of vegetation is analyzed in relation to density of human residence, first by regression analysis involving stratified distance zones and then by the recent echelon approach for characterization of surfaces. Echelons reveal structural organization of surfaces in an objective and explicit manner. The virtual surface determined by census data collected on a grid is shown to have structural correspondence with the surface representing vegetation greenness as reflected in magnitude of NDVI values computed from red and infrared bands of image data.
The complete chloroplast (cp) genome sequence of Pearl millet (Pennisetum glaucum [L.] R. Br.), an important grain and forage crop in the family Poaceae, is reported in this study. The complete cp genome sequence of P. glaucum is 138,172 bp in length with 38.6% overall GC content and exhibits a typical quadripartite structure comprising one pair of inverted repeat (IR) regions (22,275 bp) separated by a small single-copy (SSC) region (12,409 bp) and a large single-copy (LSC) region (81,213). The P. glaucum cp genome encodes 110 unique genes, 76 of which are protein-coding genes, 4 ribosomal RNA (rRNA) genes, 30 transfer RNA (tRNA) genes and 18 duplicated genes in the IR region. Nine genes contain one or two introns. Whole genome alignments of cp genome were performed for genome-wide comparison. Locally collinear blocks (LCBs) identified among the cp genomes showed that they were well conserved with respect to gene organization and order. This newly determined cp genome sequence of P. glaucum will provide valuable information for the future breeding programs of valuable cereal crops in the family Poaceae.
Programmed cell death (PCD) in the tapetum of Lathyrus undulatus L. was analyzed based on light, fluorescence and electron microscopy to characterize its spatial and temporal occurrence. Development and processes of PCD in secretory tapetal cells of Lathyrus undulatus L. were correlated with the sporogenous cells and pollen grains. At early stages of development the tapetal cells appeared similar to pollen mother cells, structurally. Concurrent with meiosis, tapetum expanded both tangentially and radially as vacuoles increased in size. Tapetal cells most fully developed at young microspore stage. However, tapetum underwent substantial changes in cell organization including nucleus morphology monitored by DAPI. The TUNEL staining confirmed the occurrence of intra-nucleosomal DNA cleavage. In addition to nuclear degeneration which is the first hallmark of PCD other diagnostic features were observed at vacuolated microspore stage intensely; such as chromatin condensation at the periphery of the nucleus, nuclear membrane degeneration, chromatin release to the cytoplasm, vacuole collapse according to tonoplast rupture, shrinkage of the cytoplasm, the increase and enlargement of the endoplasmic reticulum cisternae and disruption of the plasma membrane. After vacuole collapse due to possible release of hydrolytic enzymes the cell components degraded. Tapetal cells completely degenerated at bicellular pollen stage.
