Comparison of the initial development of four species in forest restoration plots with three different soil preparation systems in the department of Caazapa, Paraguay

The regularization of rural properties in the molds of the New Forest Code depends on the silvicultural study of the native species of the Brazilian biomes. The objective of this study was to evaluate the initial growth of five native tree species of the Atlantic Forest, with a view to their use in forest restoration projects. The following species were produced in the nursery, planted in the field, and evaluated for performance: Araucaria angustifolia, Mimosa scabrella, Trichilia claussenii, Schizolobium parahyba, and Cordia trichotoma. These species were distributed in two different areas, based on the randomized block experimental design. In experiment 1, the species A. angustifolia, M. scabrella, and C. trichotoma were distributed in three randomized blocks, each composed of 11 plants of each species. In experiment 2, the species A. angustifolia, M. scabrella, T. claussenii, and S. parahyba were distributed in three randomized blocks, each one composed of five plants of each species. In general, S. parahyba and M. scabrella showed faster development than the other species and, in this regard, are promising candidates for forest areas constitution or reconstitution in which there is interest in obtaining economic returns in less time. Araucaria angustifolia and T. claussenii showed relatively low development, whereas C. trichotoma showed intermediate development in relation to the other species studied. Despite their differences in performance, all species proved to be suitable for use in reforestation, mainly in the region where the study was developed.

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Different management practices impact on CO2 and H2O budget of wind disturbed forest sites- 5-year dataset

10.5194/egusphere-egu2020-20452 ◽

2020 ◽

Author(s):

Klaudia Ziemblinska ◽

Janusz Olejnik ◽

Marek Urbaniak ◽

Stanislaw Malek

Keyword(s):

Forest Management ◽

Forest Restoration ◽

Management Practices ◽

Soil Cover ◽

Soil Conditions ◽

Organic Layer ◽

Forest Site ◽

Forest Management Practices ◽

Soil Preparation ◽

The Impact

There is evidence of increasing severity of extreme meteorological events, which due to climate warming are also more frequent than in the past few decades. Any disturbances (either natural or anthropogenic) exert a significant influence on the forest&#8217;s functioning. In Canada and the USA, fires and insect outbreaks cause the greatest damage while in Europe wind disturbances are the main threat. Since in Poland the majority of forests are managed by the State Forests, after such events disturbed areas are almost immediately designated for reforestation. While natural regeneration still contributes the least to forest restoration, the most common practices in our country include harvesting, soil preparation (ploughing) and manual seedlings introduction, which in this sense is similar to clear-cut&#8217;s management.&#160;Once such an event happened in Poland two EC stations were set up in the area of an 80-year old pine forest, which had been wiped out by a tornado in July 2012, to asses the impact of forest management. To date, there have been more than 5 full years of continuous carbon and energy fluxes measurement, allowing insight into forest regeneration patterns due to manual reforestation, as well as differences in CO2 losses connected to chosen treatments. The two sites (Tlen I and Tlen II) differ mostly in terms of soil preparation &#8211; at Tlen I site soil was ploughed before replanting and at Tlen II soil cover remained almost intact. Additionally, at the second location, only trunks and main branches were harvested, while all uprooted stumps were left to decompose. Both meteorological and soil conditions have been investigated, with most of them not being significantly different, which allowed drawing the conclusion that observed differences in GHGs balance are most likely related to chosen forest management practices. Thorough analysis of quality checked EC data revealed that in 5-year perspective the application of traditional method (Tlen I site), mainly due to soil ploughing, resulted in much less total CO2 loss to the atmosphere, reaching C-neutrality point in only 6 years after the damage as well as better seedling growth in general in comparison to the technique, where the soil cover was not disrupted. Moreover, it seems that furrows created at the conventionally managed forest site (&#8220;double&#8221; organic layer) serve as crucial water reservoirs during water shortage periods, preventing from the pine plantation damage caused by prolonged droughts.This work advances our understanding of how different forest management practices can help to sustain the least CO2 losses on the example of wind-disturbed forests. Although, it has to be remembered that long-term studies are needed to point the best option from the perspective of climate change mitigation.&#160;

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