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[en] Aim of study: To contribute to the characterization of the origin of material used in afforestation, restoration or conservation activities by using Cp-SSR markers. Area of study: We used information from the natural range of Iberian pines, from Spain. Materials and methods: We used Iberian pines as an example to undertook gene pool characterization based on a wide Iberian sample of 97 populations from five Pinus species (Pinus halepensis, Pinus pinaster, Pinus nigra, Pinus sylvestris and Pinus uncinata). Haplotypes from each analyzed tree (derived from nine chloroplast microsatellites markers in P. halepensis and six in the rest of the species) were obtained. Based on this information we subdivided each species in regions (considering both genetic structure and its application in afforestation, restoration and conservation programs) and tested the assignation of populations to the different groups based on the genetic distance among samples. Main results: The rate of successful identification of populations among the different species was very high (> 94 %) for P. nigra, P. sylvestris and P. uncinata, high (81 %) for P. pinaster, and low (< 65 %) for P. halepensis. Research highlights: Chloroplast DNA markers from extensive population datasets can be used to assign the origin of the forest reproductive material in some pine species.
[en] Primary forest extent, loss and degradation within the Democratic Republic of the Congo (DRC) were quantified from 2000 to 2010 by combining directly mapped forest cover extent and loss data (CARPE) with indirectly mapped forest degradation data (intact forest landscapes, IFL). Landsat data were used to derive both map inputs, and data from the GLAS (Geoscience Laser Altimetry System) sensor were employed to validate the discrimination of primary intact and primary degraded forests. In the year 2000, primary humid tropical forests occupied 104 455 kha of the country, with 61% of these forests classified as intact. From 2000 to 2010, 1.02% of primary forest cover was lost due to clearing, and almost 2% of intact primary forests were degraded due to alteration and fragmentation. While primary forest clearing increased by a factor of two between 2000–2005 and 2005–2010, the degradation of intact forests slightly decreased. Fragmentation and selective logging were the leading causes of intact forest degradation, accounting for 91% of IFL area change. The 10 year forest degradation rate within designated logging permit areas was 3.8 times higher compared to other primary forest areas. Within protected areas the forest degradation rate was 3.7 times lower than in other primary forest areas. Forest degradation rates were high in the vicinity of major urban areas. Given the observed forest degradation rates, we infer that the degradation of intact forests could increase up to two-fold over the next decade. (letter)
[en] Four wetland crossings of gas pipeline rights-of-way (ROWs), located in Florida, Michigan, New Jersey, and New York, were surveyed for generation of vegetation roughly one year after pipeline construction was completed. Conventional trench-and-fill construction techniques were employed for all four sites. Estimated areal coverage of each species by vegetative strata within transect plots was recorded for plots on the ROW and in immediately adjacent wetlands undisturbed by construction activities. Relative success of regeneration was measured by percent exposed soil, species diversity, presence of native and introduced species, and hydric characteristics of the vegetation. Variable site factors included separation and replacement of topsoil, final grading of the soil, application of seed and fertilizer, and human disturbance unrelated to construction. Successful regeneration exhibited greater dependency on the first three factors listed
[en] Three elements for gauging pipeline right-of-way reclamation success on cultivated land are reviewed. Plant density measurement is a quick and early method of identifying problems. The density criteria is best measured the first season after construction. Crop production, the second element, can be measured in several ways, with weight of crop per unit area being the most definitive. However, reclaimed land may not be fully productive for several years, and control of agricultural production inputs such as fertilizer is needed if comparisons between crop production on disturbed and undisturbed land are to be valid. The third element is vegetation composition, in terms of the presence of weeds and crop sensitivity. For native rangeland, procedures are discussed for assessing reclamation in terms of plant density, vegetative cover and erosion control, weed presence, and range condition. The relationship between density and cover is noted. For forested land, assessment on the basis of density and plant composition is outlined. A sampling procedure is proposed for deciding if a reclamation site meets acceptable reclamation standards. 13 refs., 4 figs., 7 tabs
[en] Aim of the study: To evaluate the adaptive genetic variability of chestnut (Castanea sativa Mill.) populations from southern Spain in relation to bud burst and water stress. Area of study: Andalusia (southern Spain) where many chestnut groves were progressively abandoned and have become ‘naturalized’. Material and methods: A total of 126 chestnut trees from eight populations were assessed by means of nine genic microsatellite loci (expressed sequence tag simple sequence repeat markers) related to bud burst and water stress. Main results: Significant differences in genetic diversity were detected within and among populations, not found with neutral microsatellite markers. The structure analysis indicated the presence of two different gene pools. Research highlights: These results could contribute to the development of conservation strategies for this species in southern areas exposed to the effects of climate change. The genetic diversity of these populations could be useful in minimizing this risk and other predictable factors related to global change.
[en] The site of the open cast mine of the uraniferous deposit of Chanteloube is located 30 km to the north of Limoges (France). The surrounding landscape is typical of the Limousin and consists of a succession of valleys and wooded hills without any characteristic alignment. In these sectors with a complex topography, the depth of the visual range varies greatly. In the present case, the site to be restored is situated particularly well visible, along a highway with much traffic and along the flank of a major prominence, facing in the direction of this highway
[fr]Le site de l'exploitation a ciel ouvert du gisement uranifere de Chanteloube se trouve a 30 km au nord de Limoges. Le paysage environnant, typique du Limousin, est constitue d'une succession de vallees et de monts boises sans orientation caracteristique. Dans ces secteurs a topographie complexe, la profondeur du champ visuel est tres variable. Dans le cas present, le site a reamenager se trouve particulierement bien visible, le long d'une route a grande circulation et sur le flanc d'un important relief faisant face a la direction de cette route
[en] This study was conducted to evaluate three sites with vegetative communities whose dominant perennial grass species were Siberian wheatgrass-thickspike wheatgrass (Agropyron sibiricum-Agropyron dasytachyum), Indian ricegrass (Oryzopsis hymenoides), and Sandberg's bluegrass (Poa sandbergii), respectively. The principal objectives of the study were to determine the following: whether soil conditions influenced the establishment of these stands; the extent of these perennial grass species as members of the vegetation community on the Hanford Site prior to human influences, e.g., animal grazing, fire, construction, and excavation; and whether these perennial grasses could be established on other sites to be stabilized. The information obtained from this study has resulted in the following conclusions and recommendations: The depth of the soil to coarse sediments, the soil texture, and the percentage of gravel in the soil appear to affect the vegetation community on a site. It is recommended that Siberian, thickspike, and crested wheatgrass (Agropyron cristatum) be utilized for revegetation purposes on deep fine-textured soils of low gravel content. It is recommended that for revegetation purposes on shallow, coarse-textured or high gravel content soils, Indian ricegrass, needle and thread grass (Stipa comata), Sandberg's bluegrass, and sand dropseed (Sporobolus cryptandrus) be utilized. Greater success in stabilization/revegetation programs will be achieved if deep, fine-textured soils are utilized