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Understanding of stand growth information is necessary for establishing forest management plans, but accurate models for estimating ingrowth are currently lacking in Korea. This research aims to develop an ingrowth estimation equation according to various forest types using nationwide forest monitoring data by the National Forest Inventory (NFI). A two-stage approach was developed based on the ingrowth database using permanent sample plots from the 5th (2006–2010) and 6th (2011–2015) NFI. In the first stage, the ingrowth probability was estimated using a logistic function. In the second stage, the ingrowth amount was estimated using a conditional function by regression analysis. In results, a logistic regression model based on the number of sampling plot which did not result in ingrowth (Model VI), was selected for an ingrowth probability estimation equation. After performing three types of statistical test to evaluate the ingrowth estimation equation suitability, three optimal models were selected based on their respective estimation ability: Coniferous Forest (Model IV), Broad-leaved Forest (Model VII), and Mixed Forest (Model VI). The estimation ability of the proposed estimation equation was statistically verified and showed no problems of suitability or applicability. If high-quality data are continuously accumulated for comparison and contrast with the present sampling plot data through the ongoing NFI system, this research can present a new direction in ingrowth modeling for Korean forests.

The Cerrado has a wide diversity of fauna and flora, and the knowledge of its horizontal structure, in different time intervals allows the prediction of its structural and floristic characteristics. The aim of this study was to evaluate the changes in structure and composition of tree community in three fragments of Cerrado with low anthropization, in an interval of 11 years at Minas Gerais state. Rectangular plots of fixed size were sampled, measuring stem diameter and height of all living arboreal individuals with diameter at 1.30 meters above ground (DBH) ≥ 5 cm. The tree vegetation dynamics study of the areas was performed, as well as the floristic analysis and the diametric structure. Considering all fragments and years of measurement, the recruitment of trees surpassed its mortality. The basal area varied between 3.67 and 13.07 m².ha-1. The studied areas, considering all fragments and years of measurement, showed a Shannon diversity index (H') from 3.43 to 3.87 nat.ind-1 and Pielou equitability index (J') ranged an interval between 0.77 and 0.82. The similarity calculated by the Jaccard index (J), when performed per plot considering the three fragments, showed a value of 0.2653. Also, related to the development and growth of the study areas, it can be inferred that all fragments and their respective years of measurement had a J-inverse pattern. In conclusion, it can be inferred that the three fragments maintained a representative growth in number of individuals and basal area.

The Cerrado has a wide diversity of fauna and flora, and the knowledge of its horizontal structure, in different time intervals allows the prediction of its structural and floristic characteristics. The aim of this study was to evaluate the changes in structure and composition of tree community in three fragments of Cerrado with low anthropization, in an interval of 11 years at Minas Gerais state. Rectangular plots of fixed size were sampled, measuring stem diameter and height of all living arboreal individuals with diameter at 1.30 meters above ground (DBH) ≥ 5 cm. The tree vegetation dynamics study of the areas was performed, as well as the floristic analysis and the diametric structure. Considering all fragments and years of measurement, the recruitment of trees surpassed its mortality. The basal area varied between 3.67 and 13.07 m².ha-1. The studied areas, considering all fragments and years of measurement, showed a Shannon diversity index (H') from 3.43 to 3.87 nat.ind-1 and Pielou equitability index (J') ranged an interval between 0.77 and 0.82. The similarity calculated by the Jaccard index (J), when performed per plot considering the three fragments, showed a value of 0.2653. Also, related to the development and growth of the study areas, it can be inferred that all fragments and their respective years of measurement had a J-inverse pattern. In conclusion, it can be inferred that the three fragments maintained a representative growth in number of individuals and basal area. [ABSTRACT FROM AUTHOR]

Local changes caused by dams can have drastic consequences for ecosystems, not only because they change the water regime but also the modification on lakeshore areas. Thus, this work aimed to determine the changes in soil moisture after damming, to understand the consequences of this modification on the arboreal community of dry forests, some of the most endangered systems on the planet. We studied these changes in soil moisture and the arboreal community in three dry forests in the Araguari River Basin, after two dams construction in 2005 and 2006, and the potential effects on these forests. For this, plots of 20m x10m were distributed close to the impoundment margin and perpendicular to the dam margin in two deciduous dry forests and one semi-deciduous dry forest located in Southeastern Brazil, totaling 3.6ha sampled. Besides, soil analysis were undertaken before and after impoundment at three different depths (0-10, 20-30 and 40-50cm). A tree (minimum DBH of 4.77cm) community inventory was made before (T0) and at two (T2) and four (T4) years after damming. Annual dynamic rates of all communities were calculated, and statistical tests were used to determine changes in soil moisture and tree communities. The analyses confirmed soil moisture increases in all forests, especially during the dry season and at sites closer to the reservoir; besides, an increase in basal area due to the fast growth of many trees was observed. The highest turnover occurred in the first two years after impoundment, mainly due to the higher tree mortality especially of those closer to the dam margin. All forests showed reductions in dynamic rates for subsequent years (T2-T4), indicating that these forests tended to stabilize after a strong initial impact. The modifications were more extensive in the deciduous forests, probably because the dry period resulted more rigorous in these forests when compared to semideciduous forest. The new shorelines created by damming increased soil moisture in the dry season, making plant growth easier. We concluded that several changes occurred in the T0-T2 period and at 0-30m to the impoundment, mainly for the deciduous forests, where this community turned into a "riparian-deciduous forest" with large basal area in these patches. However, unlike other transitory disturbances, damming is a permanent alteration and transforms the landscape to a different scenario, probably with major long-term consequences for the environment. [ABSTRACT FROM AUTHOR]

The study was conducted at Kirjesålandet, a multistorey primeval Norway spruce [Picea abies (L.) Karst.] forest in northern Sweden. The objectives were: (1) to establish whether the presence of dead trees was associated with higher seedling density or growth; (2) to establish whether the influence of overstorey standing volume on height increment of seedlings differed between small and large seedlings; (3) to determine the time needed for seedlings to reach 1.3 m height; and (4) to estimate levels of recruitment, mortality and ingrowth into the tree layer, with equations using the relation between the height distribution and height increment of the seedling population. Seedlings (0.1-1.3 m height) and trees (diameter at breast height ≥5.0 cm) were measured on 46 circular plots. Presence of dead trees did not affect seedling density or growth. Height increment of small seedlings (0.1-0.5 m height) was unaffected by overstorey standing volume (range 13 - 333 m3 ha-1), whereas height increment of large seedlings (0.5-1.3 m height) decreased with increasing overstorey standing volume. Time to grow through the size interval 0.1-1.3 m was estimated as 58 years using height increment, and 50 years using analysis of annual rings. Seedling recruitment, annual mortality and ingrowth into the tree layer were estimated as 46 seedlings ha-1 year-1, 1.8% year-1 and 13 stems ha-1 year-1, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Stand dynamics and basal area change were determined in deciduous and gallery forest types at the Chacocente Wildlife Reserve, Nicaragua. All stems ≥10cmdbh in 4ha were tagged and identified by species and measured in 1993 and 2000. In year 2000 totally 519 stemsha−1 with a basal area of 15.62m2 ha−1 were recorded in the deciduous forest type and corresponding figures were 308 stemsha−1 and 23.13m2 ha−1 for the gallery forest type. Comparison of stem diameter and basal area distribution during this study period revealed no changes. Both forests types had a reversed J-shape diameter distribution dominated (>80%) by small stems (<30cmdbh). In the deciduous forest small stems contributed to more than half of the basal area, whereas in the gallery forest large stems (>70cmdbh) contributed to almost half the basal area. Based on a logarithmic model the mortality and recruitment rates were calculated at 4.5 and 2.5%year−1, respectively, in the deciduous forest type and 4.2 and 4.0% in the gallery forest type. The decrease in stand density in the deciduous forest type was significant whereas it was not the case for the gallery forest type. There was also a significant decrease in basal area of 1.2%year−1 in the deciduous forest and no change in the gallery forest. The recorded median diameter (dbh) increment was 0.14cmyear−1 with a range of 1.21cmyear−1 in the deciduous forest type and corresponding figures for the gallery forest were 0.24cmyear−1 and 0.71cmyear−1. Three of the five most common species in the deciduous forest, Lonchocarpus minimiflorus, Gyrocarpus americanus and Stemmadenia ovovata had mortality rates above 9%. Although L. minimiflorus and S. ovovata had recruitment rates above average the net balance was negative. Among the five most common species only Tabebuia ochracea a timber species had an annual recruitment higher than its mortality rate. Non-timber species as a group had the largest calculated negative balance between mortality and recruitment as well as between loss and gain of basal area indicating a possible anthropogenic influence. In the gallery forest Capparis pachaca was the only species, out of the most common, with a positive annual balance. In both forest types there was a higher than average calculated recruitment and basal area growth for species with no local use. [Copyright &y& Elsevier]