Evergreen Forest Types Research Articles

A pivotal nutritional potential of understory vascular plants in Patagonian forests

Native forests can support wild and domestic herbivores, but their nutritional potential of understory vascular plants is rarely explored. We analysed the composition of understory plant species and their biochemical components to reveal the nutritional potential of forest types (deciduous, evergreen, mixed) and their associated open-lands (e.g. grasslands in forestlands) in Northern Patagonia. We proposed an approach combining our data (e.g. plant composition, occurrence frequency) with bibliographic research (e.g. Scopus database) to develop our findings. Data were evaluated using descriptive statistical analyses and multivariate analyses. This study presents the nutritional values for the 20 pivotal species under examination. The results highlight the significant impact of taxonomic families on nutritional profiles, where the species that presented the most relevant occurrence frequency: the herbs T. officinale (60.4 % of total occurrence frequency-TOF) and T. repens (47.9 % TOF), the graminoid H. lanatus (58 % TOF), and the fern B. penna marina (44.4 % TOF). Multivariate analyses showed that the first two PCA axes explained 76.1 % (p = 0.001) and 10.5 % (p = 1.000) of forest type variation, with ñire forests and open-lands having the highest palatable plant coverage. Biochemical PCA axes explained 52.1 % (p = 0.024) and 22.5 % (p = 0.874) of the variation, distinguishing species by protein content and structural components. The deciduous forests exhibited the highest coverage of palatable plants, while target plants with low palatability and high coverage were predominantly found in evergreen forest types. The confirmed presence of pivotal species across forest types and open-lands underscores its nutritional potential, characterised by highly digestible dry matter, crude protein, highly digestible non-nitrogenous nutrients, and relative feed value. Considering their widespread distribution and nutritional factors, the native and non-native plants merit attention due to their pivotal nutritional potential.

Positive feedbacks and alternative stable states in forest leaf types

The emergence of alternative stable states in forest systems has significant implications for the functioning and structure of the terrestrial biosphere, yet empirical evidence remains scarce. Here, we combine global forest biodiversity observations and simulations to test for alternative stable states in the presence of evergreen and deciduous forest types. We reveal a bimodal distribution of forest leaf types across temperate regions of the Northern Hemisphere that cannot be explained by the environment alone, suggesting signatures of alternative forest states. Moreover, we empirically demonstrate the existence of positive feedbacks in tree growth, recruitment and mortality, with trees having 4–43% higher growth rates, 14–17% higher survival rates and 4–7 times higher recruitment rates when they are surrounded by trees of their own leaf type. Simulations show that the observed positive feedbacks are necessary and sufficient to generate alternative forest states, which also lead to dependency on history (hysteresis) during ecosystem transition from evergreen to deciduous forests and vice versa. We identify hotspots of bistable forest types in evergreen-deciduous ecotones, which are likely driven by soil-related positive feedbacks. These findings are integral to predicting the distribution of forest biomes, and aid to our understanding of biodiversity, carbon turnover, and terrestrial climate feedbacks.

Assessment of Soil Loss from Land Cover Changes in the Nan River Basin, Thailand

This study investigates soil loss erosion dynamics in the Nan River Basin, Thailand, focusing on the impact of land cover changes. Utilizing the Universal Soil Loss Equation (USLE) model, key factors, including rainfall erosivity, soil erodibility, topography, and land cover, are analyzed for the years 2001 to 2019. The findings reveal a substantial increase in human-induced soil erosion, emphasizing the pressing need for effective mitigation measures. Severity classification demonstrates shifting patterns, prompting targeted conservation strategies. The examination of land cover changes indicates significant alterations in the satellite image (MODIS), particularly an increase in Deciduous forest (~13.21%), Agriculture (~0.18%), and Paddy (~0.43%), and decrease in Evergreen Forest (~13.73%) and Water (~0.12%) cover types. Deciduous forest and Agriculture, associated with the highest soil loss rates, underscore the environmental consequences of specific land use practices. Notably, the increase in Deciduous forest and Agriculture significantly contributes to changes in soil loss rates, revealing the interconnectedness of land cover changes and soil erosion in ~18.05% and ~8.67%, respectively. This study contributes valuable insights for informed land management decisions and lays a foundation for future research in soil erosion dynamics. Additionally, the percentage increase in Agriculture corresponds to a notable rise in soil loss rates, underscoring the urgency for sustainable land use practices.

Structural diversity is a key driver of above-ground biomass in tropical forests

ABSTRACT Background A gamut of abiotic and biotic factors is related to the amount of above-ground biomass (AGB) produced in ecosystems. Some factors have direct and others indirect relationships with AGB. Detailed analyses in tropical forests are few but much needed for better understanding the potential impacts of global change drivers and for mitigating impacts. Aims Here, we examined the relationship between AGB and different predictor variables and quantitatively evaluated their relative importance in lowland to lower montane deciduous and lower montane – montane evergreen forest types. We hypothesised that the relationship between AGB and climate, topography, structural diversity, species diversity (alpha and beta) and phylogenetic diversity would differ between the two forest types. Methods We inventoried trees from 114 plots (each 0.1 ha) and used partial least square structural equation modelling to test the direct and indirect relationship between AGB and the predictor variables. Results We found that structural diversity variables, stem density and tree girth, were significantly and positively related to AGB in both forest types, displaying a stronger relationship in montane evergreen forests (w = 0.65 for density and 0.89 for tree girth). In the deciduous forest, alpha and phylogenetic diversity were also important factors, whereas beta and phylogenetic diversity were important in the evergreen forest. The effects of topography and climate varied between forest types, with elevation and precipitation being related to AGB directly and indirectly through their relationship with structural diversity. Conclusion Our results suggest that structural diversity is a key driver of tropical forest biomass, both directly and indirectly. This fundamental understanding can aid in the predictive efforts of biodiversity conservation and forest management.

Innovative approach to prognostic plant growth modeling in SWAT+ for forest and perennial vegetation in tropical and Sub-Tropical climates

The growth of vegetation in ecosystems is influenced by hydro-climatic factors and biogeochemical cycles. Accurately modeling annual vegetation growth dynamics is essential for eco-hydrological modeling to estimate watershed hydrologic balance and nutrient cycling under changing environmental conditions. The Soil and Water Assessment Tool (SWAT) and its upgraded version SWAT+ are process-oriented river basin models widely used. However, the temperature-based approach to plant growth simulation in tropical regions has limitations due to the importance of soil moisture availability as a key driver of plant growth. This study proposes an innovative approach that incorporates a proxy soil moisture availability index based on monthly rainfall and potential evapotranspiration ratio. This approach identifies the start of the growing season within prescribed transition months and controls leaf drop rate throughout the year, a crucial process during leaf senescence. We evaluated the reliability of this approach by comparing SWAT+ simulated Leaf Area Index (LAI), evapotranspiration (ET), and net primary productivity (NPP) with benchmark remote sensing-based datasets for three landcover classes in the Mara River Basin (Kenya/Tanzania). Our results demonstrate that the improved plant growth module in SWAT+ developed in this study can simulate temporal vegetation growth dynamics of evergreen forest, savanna grassland, and shrubland land cover types consistently with good correlations (r > 0.5) and low average bias (<10%). Thus, the SWAT+ model with the enhanced plant growth module can be a robust tool for investigating the coupled carbon, nutrient, and water cycling in tropical and sub-tropical climates.

Evergreen forest types of the central plains in Cambodia: floristic composition and ecological characteristics

Current vegetation maps show evergreen forests of Cambodia as one homogenous forest type. However, ecological field studies in the central plains demonstrated a heterogenous mosaic of different evergreen forest types, each with a unique species composition and ecological characteristics. Based on six botanical expeditions, we describe four lowland evergreen forest types: 1) riverine forest dominated by Dipterocarpus costatus (Dipterocarpaceae); 2) tall dipterocarp forest dominated by Anisoptera costata (Dipterocarpaceae); 3) swamp forest dominated by Macaranga triloba (Euphorbiaceae); and 4) ‘Sralao', an open forest with a monodominance of Lagerstroemia cochinchinensis (Lythraceae). Ordination by non‐metric multi‐dimensional scaling (NMDS) indicated that the four forest types represent well‐separated floristic entities with Sralao as the most deviant community. The highest species diversity was found in the riverine forest ( = 2.65), followed by tall dipterocarp forest ( = 2.53) and swamp forest ( = 2.34), whereas the Sralao forest had the lowest species diversity ( = 1.64). We argue that botanical fieldwork remains essential to refine vegetation maps otherwise based on remote sensing, and that knowledge of species composition is essential to conserve Indochina's vanishing evergreen forest biodiversity.

Historical trends of degradation, loss, and recovery in the tropical forest reserves of Ghana

ABSTRACT The Upper Guinean Forest region of West Africa, a globally significant biodiversity hotspot, is among the driest and most human-impacted tropical ecosystems. We used Landsat to study forest degradation, loss, and recovery in the forest reserves of Ghana from 2003 to 2019. Annual canopy cover maps were generated using random forests and results were temporally segmented using the LandTrendr algorithm. Canopy cover was predicted with a predicted-observed r2 of 0.76, mean absolute error of 12.8%, and mean error of 1.3%. Forest degradation, loss, and recovery were identified as transitions between closed (>60% cover), open (15–60% cover) and low tree cover (< 15% cover) classes. Change was relatively slow from 2003 to 2015, but there was more disturbance than recovery resulting in a gradual decline in closed canopy forests. In 2016, widespread fires associated with El Niño drought caused forest loss and degradation across more than 12% of the moist semi-deciduous and upland evergreen forest types. The workflow was implemented in Google Earth Engine, allowing stakeholders to visualize the results and download summaries. Information about historical disturbances will help to prioritize locations for future studies and target forest protection and restoration activities aimed at increasing resilience.

Anther types of angiosperms within floristic diversity of Durgawadi plateau, Northern Western Ghats of Maharashtra, India

Durgawadi plateau situated in the Northern Western Ghats of Junnar tehsil, Pune district (Maharashtra state) India comes under reserved biodiversity evergreen forest type. The continuous repetitive investigation of anther type special based on the mode of anther dehiscence considers 220 dicotyledonsyledon angiosperms species belonging to 161 genera of 66 plant families. The two main types of anther dehiscence were observed longitudinal and poricidal. Among these subtypes of longitudinal dehiscence, the extrorse dehiscence type is most commonly found in 25 families. Another sub-type of longitudinal dehiscences such as introrse dehiscence, latrorse dehiscence, and poricidal dehiscence types were found in 24, 18 &amp; 1 families accordingly. Anther longitudinal dehiscence in introrse type is most commonly observed in 98 species, followed by extrorse, latrorse, and poricidal types were found in 70, 62, and 9 taxa respectively.

An Adaptive-Parameter Pixel Unmixing Method for Mapping Evergreen Forest Fractions Based on Time-Series NDVI: A Case Study of Southern China

Spectral unmixing remains the most popular method for estimating the composition of mixed pixels. However, the spectral-based unmixing method cannot easily distinguish vegetation with similar spectral characteristics (e.g., different forest tree species). Furthermore, in large areas with significant heterogeneity, extracting a large number of pure endmember samples is challenging. Here, we implement a fractional evergreen forest cover-self-adaptive parameter (FEVC-SAP) approach to measure FEVC at the regional scale from continuous intra-year time-series normalized difference vegetation index (NDVI) values derived from moderate resolution imaging spectroradiometer (MODIS) imagery acquired over southern China, an area with a complex mixture of temperate, subtropical, and tropical climates containing evergreen and deciduous forests. Considering the cover of evergreen forest as a fraction of total forest (evergreen forest plus non-evergreen forest), the dimidiate pixel model combined with an index of evergreen forest phenological characteristics (NDVIann-min: intra-annual minimum NDVI value) was used to distinguish between evergreen and non-evergreen forests within a pixel. Due to spatial heterogeneity, the optimal model parameters differ among regions. By dividing the study area into grids, our method converts image spectral information into gray level information and uses the Otsu threshold segmentation method to simulate the appropriate parameters for each grid for adaptive acquisition of FEVC parameters. Mapping accuracy was assessed at the pixel and sub-pixel scales. At the pixel scale, a confusion matrix was constructed with higher overall accuracy (87.5%) of evergreen forest classification than existing land cover products, including GLC 30 and MOD12. At the sub-pixel scale, a strong linear correlation was found between the cover fraction predicted by our method and the reference cover fraction obtained from GF-1 images (R2 = 0.86). Compared to other methods, the FEVC-SAP had a lower estimation deviation (root mean square error = 8.6%). Moreover, the proposed method had greater estimation accuracy in densely than sparsely forested areas. Our results highlight the utility of the adaptive-parameter linear unmixing model for quantitative evaluation of the coverage of evergreen forest and other vegetation types at large scales.

Seed dispersal modes of tree species and their relation with altitudinal gradient from tropical forests of Eastern Ghats, India

The present study reports the seed dispersal modes of tree species and their relationship with altitudinal gradient from six tropical forests of Eastern Ghats located in India. Anemochory, autochory and zoochory are the three major types of seed dispersal modes recognized for the 272 tree species recorded from a total of 120 0.5 ha area. The predominant dispersal mode is zoochory with 58% of the total tree abundance and 69% of total species richness, followed by autochory with 30% and 19%, and anemochory 12% and 12%, respectively. One way ANOVA revealed that the species richness as well as tree abundance of the three dispersal modes varied significantly across the six tropical forest sites. Regression analysis revealed that both the tree species richness and abundance of zoochory dispersal mode had positive relation with altitude of forest location, while, no such relation was observed for the other two dispersal modes. This study shows that the zoochory increases in species richness and tree abundance with increasing altitude. This may be attributed to high rainfall supporting evergreen forest types with high ratio of animal dispersed tree species in forests at high altitude. However, further studies on these aspects are warranted to draw a significant statement. The predomination of zoochory dispersal mode in this study is comparable with earlier studies in tropical forests elsewhere.

Examining phenological variation of on-year and off-year bamboo forests based on the vegetation and environment monitoring on a New Micro-Satellite (VENµS) time-series data

ABSTRACT Moso bamboo is an evergreen plant that extensively distributes in subtropical regions. Comparing to other forest types, Moso bamboo forest has some unique characteristics: high growth rate, short harvesting rotation, and on/off-year phenomenon. Plant phenology plays an important role in regulating carbon sequestration of the bamboo forest ecosystem. However, it is a challenge task to capture the phenological features of Moso bamboo forests on a regional scale due to frequent change of canopy structures and lack of high spatiotemporal remotely sensed data. The Vegetation and Environment monitoring on a New Micro-Satellite (VENµS) data with high spatiotemporal resolution provide the potential to examine the seasonal change of Moso bamboo forests. This research employs the VENµS time-series data (from January 2018 to December 2019) to analyse the spectral characteristics of on-year/off-year Moso bamboo forests and other two evergreen forest types (i.e., broadleaf forest and coniferous forest). The optimal spectral ranges for examining the seasonal variation of bamboo forests were determined. Three red-edge-based vegetation indices were reconstructed using the Harmonic analysis of time series (Hants) and compared. Red-edge position index (REPI) was selected to identify different phenological periods of Moso bamboo forests and other evergreen forest types. The results show that the spectral range of 730–920 nm in the VENμS data is sensitive to seasonal variation of Moso bamboo forests. The REPI can more effectively identify the two-year growing cycle of the bamboo forests than other vegetation indices, especially the bamboo shoots period. The start of the growing season of the off-year bamboo forest is approximately 50 to 60 days earlier than on-year bamboo forest. The results provided time-series phenological datasets of on-year and off-year Moso bamboo forests, which is valuable for local governments to conduct better ecological management and decision-making.

High spatial resolution ozone risk-assessment for Asian forests

Background tropospheric ozone (O3) is increasing particularly over China and India, and becomes a major threat to Asian forests. By using the coupled WRF-Chem model at high spatial resolution (8 km) over Asia in 2015, we showed that both standards AOT40 (European) and W126 (United States) underestimated the O3 risk to deciduous forests and overestimated it to evergreen forests compared to the biologically based metric POD1. Both metrics AOT40 and W126 showed different spatial distribution and exceedance extent with respect to POD1. We found very high potential of O3 impacts on deciduous forest growth in Asia, while potential O3 impacts on evergreen forest types were lower. The most limiting factors were light availability, soil water content and air temperature (65%, 29% and 6%, respectively), making this region of the globe at high O3 risk for deciduous species and at medium O3 risk for evergreen species. For the first time, the O3 risk to Asian forests was quantified at high spatial resolution; and our results suggested: (i) a relevant overestimation of O3 risk to evergreen forests when using AOT40 and W126 relative to the more biologically based POD1 metric; and (ii) a significant underestimation of O3 risk to the boreal deciduous forests when using AOT40 and W126 relative to POD1 because of stomatal aperture permissive condition.

Flora of Khandagiri and Udayagiri: An Urban Heritage of Odisha

The Khandagiri and Udayagiri hills are situated in the heart of temple city Bhubaneswar with about 411 species of plants. The vegetation here more or less conforms to tropical low mixed and semi evergreen forest and dry evergreen forest type vegetation, characteristic of sandstone hills that are similar to Chandaka-Dampada-Nandanakanan range. Additionally, the area is home to over 100 species of medicinal plants, wild edible fruit plants and several botanically interesting species. Gardenia latifolia, Memecylon umbellatum, Pterospermum xylocarpum, Alphonsea madraspatana, Desmodium alysicarpoides, Syzygium cerasoides, Canthium dicoccum, Manilkara hexandra, Sarcostemma acidum, Croton caudatus are some of the characteristic plants found in this hill. The paper highlights the needs of conservation of this unique threatened habitat which might help in its long-term protection and conservation.

Initial Responses in Growth, Production, and Regeneration following Selection Cuttings in Hardwood-Dominated Temperate Rainforests in Chile

Hardwood-dominated forests in south-central Chile have shade-tolerant and mid-tolerant tree species capable of regenerating and growing well in partial shade. To test the potential for using an uneven-aged silviculture in these forests, we established single-tree selection treatments at two mid-elevation sites within the Evergreen forest type in the Coastal range (Llancahue and Los Riscos, 40–42° S Lat). They had an average initial basal area of 70–80 m2 ha−1. In each stand, we established four 2000 m2 plots with a residual basal area of ~40 m2 ha−1, and four with a residual basal area of ~60 m2 ha−1. We planned for a maximum residual diameter of 80 cm, but needed to leave 20%–25% of the residual basal area in larger trees due to their great abundance in these old-growth forests. We re-measured these plots 5–6 years after the cuttings. We used mixed-effects models to evaluate the periodic annual increment (pai) in diameter and the abundance of tree regeneration, and linear models to evaluate ingrowth and changes in the basal area and volume. At Llancahue, the diameter pai of individual trees was significantly greater in the treatment with lower residual densities, especially for mid-tolerant species in lower diameter classes (5–20 cm). At both sites, the pai in the stand basal area and volume was greater in the more heavily stocked treatment, but differences were significant only at Llancahue. Regeneration was dominated by shade-tolerant species at both sites but was more abundant and more diverse at Llancahue. Taller tree regeneration (50–&lt;200 cm) significantly increased after the cuttings at both sites, while small regeneration (5–&lt;50 cm) overall remained at pre-cut levels. This pattern was similar for mid- and shade-tolerant species. However, we found no differences in regeneration responses between the lower and higher levels of the residual basal area. Sapling densities did not differ at both sites for shade-tolerant species, but for mid-tolerant species these were more abundant at Los Riscos. While both sites had many similar trends after implementing selection cuts (a greater individual growth in the treatment with lower basal areas but a higher stand-level growth in the treatment with a high basal area, more abundant regeneration of shade-tolerant species, etc.), they illustrate a differential potential for implementing uneven-aged silviculture, especially due to site-species interactions. These results are a first step towards evaluating the prospects for selection cuttings in these experiments and elsewhere in Valdivian temperate rainforests.

Differential Early Performance of Two Underplanted Hardwood Tree Species Following Restoration Treatments in High-Graded Temperate Rainforests

Raulí (Nothofagus alpina (Poepp. &amp; Endl.)) and Ulmo (Eucryphia cordifolia Cav.) are mid-tolerant tree species in the Coihue-Raulí-Tepa (ca. 0.55 mill ha) and Evergreen (ca. 4.1 mill ha) forest types in south-central Chile, respectively. These species have been selectively logged in old-growth forests especially during the 20th century, Raulí mostly for its highly valuable timber, and Ulmo for its highly demanded firewood and bark for the tannery industry. Natural regeneration of these species occurs mostly through canopy gaps, but it can be retarded, or even inhibited, when the cover of the understory vegetation becomes unusually dense, such as in high-graded forests. Although underplanting is possible for these species, the knowledge about their growth in forest understories is scarce, and necessary to inform restoration programs. Therefore, we evaluated short-term responses (two years) of underplanted containerized seedlings in root-collar diameter, height, stem volume, and in the slenderness index, as a function of canopy openness (%, continuous variable) and three restoration treatments (categorical variables, plus one control treatment) at two different sites with high-graded old-growth forests for each forest type. By using generalized linear mixed-effects models (GLMMs) we determined that Raulí was more sensitive to the influence of both canopy openness and restoration treatments, while Ulmo was mostly influenced by canopy openness. Specifically, Raulí was positively influenced by canopy openness and restoration treatments in all response variables except for the slenderness index. Conversely, Ulmo was influenced by canopy openness in all response variables except the slenderness index, which was influenced by both predictor variables (canopy openness and restoration treatments). Thus, prospects for restoration with these species are discussed, including possible ontogenetic changes in their responses to light that may demand continuous silvicultural operations to recover the productive and functional roles of these species in these forest ecosystems.

Changing patterns in the distribution of the Mayaro virus vector Haemagogus species in Trinidad, West Indies

The Mayaro virus disease (MAYVD) is an emerging mosquito borne zoonosis that was first reported on the island of Trinidad in 1954. The viral agent for this disease is known to presently be endemic to Central and South America. The enzootic cycle of the Mayaro virus (MAYV) is not fully characterized, though primates are thought to be the main reservoir with Haemagogus species of mosquitoes as the primary vector. This virus has been responsible for several sporadic cases of infections and limited outbreaks, but it is postulated that the MAYVD will become a major epidemic in the future, following in the steps of the recent pandemics caused by Chikungunya and Zika viruses. Mitigating possible major outbreaks of MAYVD in the future would require effective strategies for vector control, for which knowledge on the ecology and distribution of the Haemagogus mosquitoes would be vitally important. In Trinidad, Haemagogus species have only been reported in the northwestern peninsula of the island based on studies up to 1995. However, no recent investigations have been completed to determine the status of this important vector on the island. The aim of this study was to investigate the current spatial distribution of Haemagogus species in the island of Trinidad, West Indies. Adult Haemagogus (Hag.) mosquitoes and larvae were surveyed during a twenty-month period using human bait trapping and ovitraps in major forested areas on the island. Mosquito species were identified using classical taxonomic keys. Haemagogus species were widespread and found in all forest types surveyed. Hag. janthinomys (85.7%) was the most widely distributed and dominant species on the island. Lower levels of Hag. leucocelaneus (7.3%), Hag. equinus (6.4%) and Hag. celeste (0.6%) were also collected. Overall, the proportion of mosquitoes collected in the wet season (June–December) was 3.5 times more than in the dry season (January–May). Mangroves, young secondary forests, semi-evergreen and evergreen forest types had relatively high mean abundance levels of Haemagogus species as compared to deciduous and montane forests. Proximity analysis suggests that population settlements within a 1 km buffer of the forest peripherals may be at risk for any emerging arboviral disease associated with these mosquito vectors. Haemagogus species showed a much wider distribution in Trinidad as compared to previous reports from up to 20 years ago and were prevalent in areas with no known presence of non-human primates. Since the MAYV has been previously implicated in causing infections in vertebrate hosts like rodents, birds and small mammals, the findings of this study suggest that there may be alternative hosts and reservoirs of this virus in the sylvatic cycle in Trinidad, other than primates. This has significant epidemiological implications for mosquito-borne viral infections in the region.

Forest Type Classification Based on Integrated Spectral-Spatial-Temporal Features and Random Forest Algorithm—A Case Study in the Qinling Mountains

Spectral, spatial, and temporal features play important roles in land cover classification. However, limitations still exist in the integrated application of spectral-spatial-temporal (SST) features for forest type discrimination. This paper proposes a forest type classification framework based on SST features and the random forest (RF) algorithm. The SST features were derived from time-series images using original bands, vegetation index, gray-level correlation matrix, and harmonic analysis. Random forest-recursive feature elimination (RF-RFE) was used to optimize high-dimensional and correlated feature space, and determine the optimal SST feature set. Then, the classification was carried out using an RF classifier and the optimized SST feature set. This method was applied in the Qinling Mountains using Sentinel-2 time-series images. A total of 21 SST features were obtained through the RF-RFE method, and their importance was evaluated using the Gini index. The results indicated that spectral features contribute the most to separating shrubs, spatial features are more suitable for discrimination among evergreen forest types, and temporal features are more useful for evergreen forest, deciduous forest, and shrub types. The forest type map was generated based on the optimal SST feature set and RF algorithm, and evaluated based on an agreement with the validation dataset. The results showed that this integrated method is reliable, with an overall accuracy of 86.88% and kappa coefficient of 0.86, and can support forest type sustainable management and mapping at the local scale.

Impacts of climate change on the gross primary production of Italian forests

The impact of climatic change should not be dramatic over Italian forests in terms of GPP, which should increase particularly for evergreen forest types. This positive effect is less marked for deciduous forests. The increasing trend should be reduced by the end of the century for all forest types except mountain conifers because of increasing temperature and decreasing rainfall. Estimating the spatial and temporal variability of forest gross primary production (GPP) is a major issue of applied ecology, particularly in relation to ongoing and expected climate change. The current study proposes a methodological framework for analyzing large-scale forest responses to climate change in terms of GPP. The methodology utilizes the GPP estimates of an NDVI-driven model, C-Fix, to assess the performance of a biogeochemical model, BIOME-BGC. The two models were first applied at 1-km pixel scale in Italy over a period of 15 years (1999–2013). The model outputs, aggregated on annual basis for the main Italian forest types, were inter-compared and analyzed in relation to major meteorological drivers (i.e., temperature and water-limiting factors). C-Fix and BIOME-BGC responded similarly to these major drivers, which supported the application of BIOME-BGC as a prognostic tool to simulate the GPP during three time slices of the RCP4.5 climate scenario. The results obtained highlight how the importance of spring temperature and water availability is diversified among the forest types in determining changes of forest GPP all over the Italian peninsula in a future climate.

Development of 26-year-old mixed forests following different regeneration cutting treatments in Andean temperate rainforests of south-central Chile

Tree regeneration following even-aged silvicultural methods in the evergreen forest type (EFT) has been scarcely studied in Chile, although this is the largest forest type in a region of highly productive native forests. In 1981/1982 a total of nine 1.44-ha experimental units with old-growth forests of the EFT were subjected to block clearcutting (BCC), strip clearcutting (SCC) and reserve shelterwood cutting (RSC) methods (three replicates in each case) in the Andes range in south-central Chile (41°35′S–72°35′W). The resulting second-growth forest stands following these cuttings were evaluated in terms of composition, density, basal area, mean diameter and height after four and 26 years (432 4 m2 plots in 1986, and 78 100 m2 plots in 2008). Four years after cutting, there were >one million tree seedlings per hectare in more than 10 species. In all experimental units one shade-tolerant species (Amomyrtus luma), one midtolerant species (Eucryphia cordifolia) and two very shade-intolerant species (Embothrium coccineum and Weinmannia trichosperma) comprised between 69 and 74% of the total density. The SCC favored a greater relative dominance of all the more shade-tolerant species, and the BCC treatment was more favorable for pioneer species (in addition to E. coccineum and W. trichosperma also Drimys winteri, Caldcluvia paniculata and Nothofagus nitida). At age 26, the short-lived E. coccineum dominated in all treatments, and its major coexisting species in terms of tree density were the midtolerants D. winteri, Eucryphia cordifolia and N. nitida, and the shade-tolerants Laureliopsis philippiana and A. luma. However, the BCC significantly favored the development of N. nitida and D. winteri (three times more basal area than in the other treatments), which might be explained by increasing soil moisture that occurs in this region following this type of disturbances. While these treatments did not show significant differences in mean diameters and dominant height, the BCC and SCC treatments allowed denser, diverse and well-stocked second-growth forests compared to the RSC method, illustrating the differences between truly even-aged and two-aged silvicultural methods upon these variables. Overall, these forests show a high resilience, rapid reorganization and high productivity following the application of even-aged silvicultural methods.

Species Discrimination of Plantations in Subtropical China Using 4-Band VHR Imagery and an Operational Image Analysis Framework

Species information of forest plantations is of central interest to forest managers, especially under the current pressing demand for more structurally and functionally healthy and diverse plantations in China. In this study, five evergreen forest types were discriminated using a 4-band very high spatial resolution (VHR) satellite image with an operational image analysis framework which particularly involves a two-step feature selection (TSFS) method and image textural orientations. Two hundred and twenty-five object-based spectral and textural features were retrieved as candidates for the TSFS method to select the most influential feature subsets. Five schemes using random forest classification with optimal user-defined parameters were tested and compared. Both qualitative and quantitative assessment results indicated that the best scheme is the integration of spectral and textural features with individual orientations. The feature selection rate as low as 4% for the optimal scheme reflected the high effectiveness of the TSFS. The geometric intersections showed that many archive even-aged pure coniferous plantations were in fact mixed with nonconiferous species with different proportions (8.05–16.02%) and spatial aggregation patterns over very rugged terrain. Special management strategies are needed to perform the transition of pure coniferous plantations into more structurally balanced coniferous-broadleaved mixed woodland in subtropical China.