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Genetic structure of a naturally regenerating Scots pine population tolerant for high pollution near a zinc smelter.
1992
Prus Glowacki W. | Nowak Bzowy R.
Natural regeneration of Norway spruce ecosystems in the Krkonose mountains: conditions and constraints
2002
Cudlin, P. | (Academy of Sciences of Czech Republic, Ceske Budejovice (Czech Republic). Institute of Landscape Ecology) | Chmelikova, E. | Falta, V. | Gronsky, R. | Sera, B. | Polak, T.
Results on germination, growth and mortality of Norway spruce seedlings during period 1994-2000 in various types of soil cover were summarized and evaluated. The years 1992 and 1995 were recorded as high seed production years, while the year 2000 is considered as the low seed production year. In 1999 natural seedlings from various soil covers were examined for lateral root and root tip development. The results of germination and surviving of Norway spruce seedlings are discussed in relationship with the stage of the decline of Norway spruce ecosystems
Afficher plus [+] Moins [-]Conditions of natural regeneration of Norway spruce ecosystems in the Krkonose mountains
2002
Cudlin, P. (Academy of Sciences of the Czech Republic, Ceske Budejovice (Czech Republic). Institute of Landscape Ecology) | Godbold, L. | Bonifacio, E. | Egli, S. | Fritz, H. W. | Chmelikova, E. | Kowalik, P. | Martinotti, M. G. | Moravec, I. | Nicolotti, G. | Zanini, E.
The aim of the international EU project was to characterize the status, conditions, and constraints for natural regeneration of Norway spruce (Picea abies [L.] Karst.) ecosystems in different stage of forest decline on three permanent research plots in the Giant Mts., to assess whether the biotechnological measures are necessary to support a natural regeneration at each plot. There were not ascertained any fundamental differences in basic soil types of three permenent research plots. No significant differences were observed in diversity of fungal and bacterial rhizospheric populations, including ectomycorrhizal symbionts
Afficher plus [+] Moins [-]Does invasion by Pteridium aquilinum (Dennstaedtiaceae) affect the ecological succession in Atlantic Forest areas after a fire?
2022
Carvalho, Thayane Ferreira | Carvalho, Aline Cristina | Zanuncio, José Cola | de Oliveira, Marcio Leles Romarco | Machado, Evandro Luiz Mendonça | José, Anderson Cleiton | Santos, José Barbosa | Pereira, Israel Marinho
Pteridium aquilinum (Dennstaedtiaceae) colonization affects ecological and restoration processes. The knowledge of the impacts on the ecological succession by this species allows the use of restoration strategies in invaded environments. This work aimed to evaluate the floristic composition, diversity, structure, density, basal area, height, and diameter of natural regeneration in three areas of the Atlantic Forest in the Serra do Espinhaço Biosphere Reserve in an area invaded by P. aquilinum after a fire. Three environments with different coverage intensities by P. aquilinum were studied, and the plants over 10 cm in height or 5 cm in canopy diameter were measured. The floristic composition and diversity were analyzed using indices presented by Chao, Fisher, Margalef, Pielou, Shannon-Weaver, and Simpson, and similarity was evaluated by the Jaccard index. Species density, basal area, height, and canopy diameter classes were also evaluated. The floristic composition, diversity, structure of natural regeneration, density, and basal area were higher in post-fire areas with a lower coverage by P. aquilinum. The topsoil coverage with plant litter and the possible effect of P. aquilinum allelopathy probably reduced the species richness and diversity. The proportion of plants from the lowest height and canopy diameter classes was higher under moderate coverage by P. aquilinum. The reduction in the floristic composition, diversity, number of species, and basal area in post-fire areas colonized by P. aquilinum is probably due to this species aggressiveness. The population of this plant is high, accumulating large quantities of plant litter as a physical barrier preventing light and propagules from reaching the soil, reducing the germination of the seed bank and, consequently, the natural regeneration. The floristic composition, diversity, structure of natural regeneration, density, and basal area were lower in areas with higher coverage by P. aquilinum. The proportion of plants in the most significant height and canopy diameter classes was higher with reduced coverage by P. aquilinum. The P. aquilinum reduced forest succession in areas after a fire.
Afficher plus [+] Moins [-]Shade moderates the drought stress on saplings of Beneh (Pistacia atlantica Desf. subsp. mutica) in semiarid areas of Iran
2022
Sadeghzadeh Hallaj, Mohammad Hosein | Azadfar, Davoud | Mirzaei Nodoushan, Hossein | Eskandari, Saeedeh | Tiefenbacher, John
Pistacia atlantica Desf. (Beneh) is an important woody species that has been facing significant challenges to its natural regeneration and reforestation in Iran. This study investigates the interaction of soil moisture and shade on growth, chemical contents, and morphological and physiological characteristics of Beneh saplings. One-year-old Beneh saplings were treated with varying amounts of soil moisture (20, 50, and 100% of field capacity) and shade (0, 30, and 50% of full sunlight) in a split-plot experiment of a randomized complete block design in semiarid conditions of the Alborz Research Station of the Research Institute of Forests and Rangelands (RIFR) in Iran. The results indicate that soil moisture significantly affects the water content of the leaf, total chlorophyll, proline content, activity of catalase enzyme, leaf dry biomass, leaflet area, and dry stem biomass in the leaf. Shade significantly affected total chlorophyll, catalase enzyme activity, specific leaflet area, relative water content of the leaf, proline content, dry root biomass, and leaflet area. The interaction of shade and soil moisture significantly affected seedling height, catalase enzyme activity, specific leaflet area, and nitrogen and potassium content of the leaf. Shade moderates the stress of drought on Beneh saplings, but shading of Beneh saplings is not recommended in conditions where there is no concern about soil moisture. These conclusions can be used to improve the production of Beneh saplings in nurseries.
Afficher plus [+] Moins [-]In situ conservation of endangered tree species (Elaeocarpus venustus Bedd.) habitated in Agasthiyamalai Biosphere Reserve, Southern Western Ghats, India
2021
Elaeocarpus venustus is an endemic as well as endangered tree species habitated in the wet evergreen forests of Southern Western Ghats (SWG), India. Due to insufficient natural regeneration, low seedling tendency, and prevailing anthropogenic disturbances, their distribution has been shrinking in their native environment. Towards conserving this endangered species, we have attempted to propagate E. venustus in its habitat by adopting vegetative propagation techniques of cutting and air layering through growth hormones. Significant growth has been observed by providing 2 mM concentration of indole-3-butyric acid (IBA) for both cutting and air layering. Higher rooting response has been observed through cutting and air layering techniques during monsoon periods. Based on the results of the study, we suggest that the cutting and air layering techniques can be employed as promising strategies towards the in situ conservation and promotion of Elaeocarpus venustus tree species as well as other endangered species in Western Ghats.
Afficher plus [+] Moins [-]The use of ALS, botanical, and soil data to monitor the environmental hazards and regeneration capacity of areas devastated by highway construction
2016
Kopeć, Dominik | Woziwoda, Beata | Forysiak, Jacek | Sławik, Łukasz | Ptak, Agnieszka | Charążka, Edyta
The impact of viaduct construction on the vegetation of a river valley was studied in Central Poland (Natura 2000 site PLH100006). The research aimed at assessing the suitability of ALS (airborne laser scanning), soil, and botanical data for monitoring the environmental effects of right-of-way reclamation 1 year after the road construction. Based on the data mentioned above, the following problems were identified: changes in topography and hydrological conditions of the valley as a result of improper land levelling, the use of inadequate soil for reclamation, no spontaneous regeneration of natural vegetation along the entire right-of-way, as well as the abundant occurrence of invasive species. The results of analysis were used to define strategies for mitigation of adverse impacts of the viaduct construction.
Afficher plus [+] Moins [-]The littoral zone in the Three Gorges Reservoir, China: challenges and opportunities
2013
Yuan, Xing-zhong | Zhang, Yue-wei | Liu, Hong | Xiong, Sen | Li, Bo | Deng, Wei
For flood control purpose, the water level of the Three Gorges Reservoir (TGR) varies significantly. The annual reservoir surface elevation amplitude is about 30 m behind the dam. Filling of the reservoir has created about 349 km(2) of newly flooded riparian zone. The average flooding period lasts for more than 6 months, from mid-October to late April. The dam and its associated reservoir provide flood control, power generation, and navigation, but there are also many environmental challenges. The littoral zone is the important part of the TGR, once its eco-health and stability are damaged,which will directly endanger the ecological safety of the whole reservoir area and even the Yangtze River Basin. So, understanding the great ecological opportunities which are hidden in littoral zone of TGR (LZTGR) and putting forward approaches to solve the environmental problems are very important. LZTGR involves a wide field of problems, such as the landslides, potential water pollution, soil erosion, biodiversity loss, land cover changes, and other issues. The Three Gorges dam (TGD) is a major trigger of environmental change in the Yangtze River. The landslides, water quality, soil erosion, loss of biodiversity, dam operation, and challenge for land use are closely interrelated across spatial and temporal scales. Therefore, the ecological and environmental impacts caused by TGD are necessarily complex and uncertain. LZTGR is not only a great environmental challenge but also an ecological opportunity for us. In fact, LZTGR is an important structural unit of TGR ecosystem and has special ecosystem services function. Vegetation growing in LZTGR is therefore a valuable resource due to accumulation of carbon and nutrients. Everyone thinks that the ecological approach to the problem is needed. If properly designed, dike-pond systems, littoral woods systems, and re-created waterfowl habitats will have the capacity to capture nutrients from uplands and obstruct soil erosion. Ecological engineering approaches can therefore reduce environmental impacts of LZTGR and optimize ecological services. In view of the current situation and existing ecological problems of LZTGR, according to function demands such as environmental purification, biodiversity conservation, and vegetation carbon sink enhancement, we should explore the eco-friendly utilization mode of resources in LZTGR. Ecological engineering approaches might minimize the impacts or optimize the ecological services. Natural regeneration and ecological restoration in LZTGR are valuable for soil erosion decrease, pollutant purification, biodiversity conservation, carbon sink increase, and ecosystem health maintenance in TGR.
Afficher plus [+] Moins [-]Natural regeneration of beech under ecologically difficult conditions
1998
Penaz, J. | Martinek, J. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Fakulta Lesnicka a Drevarska)
In the region of Knehyne-Velka Stolova in the Moravian-Silesian Beskids, where there are ecologically difficult conditions for functioning forest ecosystems, possibilities were studied for the naturat regeneration of beech. The study of problems was particularly related to generative propagation, however, cases of vegetative propagation were also found. Potential possibilities of regeneration are related to the seed year 1995. Rooting ability of layered branches or lying beech trees wes studied. Analysis is given of a rooting beech branch.
Afficher plus [+] Moins [-]Regeneration processes of a Norway spruce virgin forest of the Stata nature reserve Pilsko in the Oravian Beskids Mts. [Slovak Republic]
1998
Saniga, M. (Technicka Univ., Zvolen (Slovak Republic). Lesnicka Fakulta)