Evaluation of red sanders (Pterocarpus santalinus L.f.) germplasm for conservation and breeding

天然次生林蒙古栎种群空间格局

Do climate and human disturbance determine the sizes of endangered Metasequoia glyptostroboides trees in their native range?

The surveys were conducted in natural populations of Haldina cordifolia in the forest areas of three states of central India namely Madhya Pradesh, Chhattisgarh and Maharashtra. Based on the growth parameters of the individual tree, a total of thirty trees from nine forest divisions of these three states were selected as candidate plus trees (CPTs). Variation was observed in girth at breast height (GBH), total height, and clear bole height (CBH) of trees surveyed. The maximum GBH was recorded in the CPTs of Balrampur (243.75 cm) while the minimum was recorded in Balaghat (115 cm). The maximum height of CPTs was recorded in Dindori (30.25 m) while the minimum was recorded in Allapalli (19 m). The maximum CBH% of total height was recorded in Bilaspur (44.22) while the minimum was recorded in Katghora (37.31). Higher GBH and height of trees may be resulted due to more age of trees. CPTs of Bilaspur were of middle age and showed the highest CBH% (44.22) and relatively low GBH and height when compared with those of Dindori and Balrampur. With age, the trees of Bilaspur will gain more height and girth which will result in higher yield.

Land‐use intensification has increased soil erosion through biodiversity loss, which affects ecosystem properties and services owing to changes in species compositional and structural diversity. However, information is limited on how land‐use intensity (LUI) affects soil erosion through species compositional diversity, structural diversity and ecosystem properties. In this study we monitored soil erosion in 15 plots over 12 consecutive months on tropical Hainan Island, where land‐use changes and biodiversity loss have been severe. We quantified the direct and indirect effects of LUI, species compositional diversity (plant species diversity and evenness) and structural diversity (tree diameter and height diversity), and ecosystem properties on soil erosion using Bayesian structural equation models (BSEM). The optimal BSEM accounted for 69% of the variation in soil erosion. The LUI did not affect soil erosion directly but showed indirect impacts via species diversity, tree height diversity, and ecosystem properties. Both high species diversity and tree height diversity reduced soil erosion directly and indirectly by promoting root length density (an ecosystem property), but tree height diversity mediated the more important indirect effect of LUI on soil erosion than species diversity and ecosystem properties. We provide evidence for loss of species diversity and tree height diversity as a result of LUI leading to aggravated soil erosion, but the impact of the latter was more serious. Therefore, we emphasize that maintenance of tree height diversity through management practices may be an effective approach to control soil erosion in the context of drastic land‐use changes in tropical areas.

Forty-two genotypes were evaluated for juvenile wood yield and its components at three locations in Bihar, India. A significant difference was observed among the genotypes for all the characters under study. The highest value of genotypic and phenotypic coefficients of variation was observed in juvenile wood volume followed by diameter at breast height (DBH). Characters like plant height, clear bole height, crown diameter number of branches, angle of branch, diameter of branch, and length of branch showed moderate values for genotypic and phenotypic coefficients of variation. Very high heritability was estimated for clear bole height, crown diameter, angle of branch, and length of branch. Diameter and plant height showed moderate to high heritability. Relatively genetic advance expressed in percentage of mean or genetic gain was observed the highest in volume (30.86%), DBH (18.96), clear bole height (17.19%), angle of branch (17.39), length of branch (19.53), and in plant height (11.87%). Juvenile wood volume per plant showed significant and positive correlation with height (0.619), diameter (DBH, 0.770), clear hole height (0.305), number of branch (0.372); and positive association with crown diameter (0.145), angle of branch (0.055), diameter of branch (0.251), length of branch (0.200), and survival (0.166); and significant negative correlation with taper (−0.499) at the phenotypic level. In phenotypic path analysis diameter (DBH, 0.702), plant height (0.169), crown diameter (0.121), taper (0.027), and survival (0.050) showed positive direct effect on juvenile wood volume. The direct impact of the same through clear bole height (−0.366), number of branch (−0.130), angle of branch (−0.228), and length of branch (−1.567) was negative. Hence it is suggested that due importance should be given to diameter (DBH), plant height, crown diameter, diameter of branch, taper, and survival for selection of superior plant with high juvenile wood yield potential in poplar.

Plant functional traits and tree size inequality improved individual tree height prediction of mid-montane humid evergreen broad-leaved forests in southwest China

The legacy of climate variability over the last century on populations' phenotypic variation in tree height

Eighteen clones of Eucalyptus tereticornis (Sm.) were evaluated for three years by adopting randomized block design for various growth parameters at Hoshiarpur, Punjab, India and compared with two checks. Significant variations were recorded for height, diameter at breast height (DBH) and clear bole height (CBH). The broad sense heritability was low to moderate for both height and CBH. The genetic gain for height and CBH increased substantially per se with the increase in age of trees. The average genetic gain for three years was recorded maximum for height (159.60%) followed by DBH (110.97%) and CBH (70.34%). Clone 17 attained maximum DBH over other genotypes for second and third year followed by clones 14 and 11. Clone 5 showed an upward trend for DBH and maintained its superiority for CBH as the age of the tree increased. Similarly, clone 11 changed its ranking from 9th to 8th to 3rd for DBH and from 9th to 4th to 2nd for CBH, respectively for the age of one, two and three years. Nonetheless, clones 6 and 10 performed poorly for all the characters studied. Clones 17, 14 and 5 were found to be the most promising clones for commercial deployment.

Twenty five plus trees of dek were selected from agro-climatic regions of Haryana, Punjab and Uttrakhand. The plus trees were selected on the basis of the different characters of economic importance viz. straightness, clear bole height, self-pruning ability, acute branch angle etc. Among all the plus trees the maximum tree height was observed in MC21 (17.9 m) whereas, the minimum in MC3 (6.5 m). The girth at breast height (gbh) of the selected plus trees varied from 60.9 to 180.8 cm and clear bole height was recorded highest from MC-21 closely followed by MC-13. The correlation among morphological traits of selected plus trees exhibited that clear bole height had positive and highly significant association with the tree height (r = 0.941) closely followed by crown spread (N-S direction) (r = 0.910). At the age of six months, progeny from MC-18 showed maximum shoot length (98.59 cm) followed by MC-16 and MC- 17 progenies. However, the highest root length was observed in the progenies from MC12 (20.84 cm) closely followed by MC-22 (20.46 cm) and MC13 (20.06 cm) progenies. The highest collar diameter was observed in progeny MC17 (13.73 mm) and lowest in MC5 (4.89 mm). The significant variation in growth attributes of progenies of selected plus tees at juvenile stage may be exploited for subsequent breeding programme and establishment of seed orchard for production of quality planting material of this versatile tree species.

ABSTRACTLitsea glutinosa (Lour.) C.B. Rob., one of the important non-timber forestry species in Central India, is represented by highly fragmented populations and has been drastically reduced for the last 40 years, promulgating government ban on its extraction. In the present investigation, we investigated variation for important morpho-metric traits, i.e. tree height (m), clear bole height (m), girth at breast height (cm), crown radius (m), crown diameter (m), crown height (m), number of primary branches, leaf area (cm2), leaf weight (gm), specific leaf area (cm2/g), bark wt/unit area (g), and their relationship. Investigation revealed existence of high level of variation for clear bole height, crown diameter, girth at breast height, and crown radius. A critical perusal of character correlation and path analysis revealed that tree height followed by crown radius, girth at breast height, and number of branches had the highest positive direct effect on bark weight/unit area. These traits should be included in the selection criteria for L. glutinosa. The observed high estimates of genetic variation for morpho-metric traits are, however, in contrast to the established relationship between genetic variation and population size. Populations of Balaghat and Chhindwara localities should be given due considerations for in situ conservation as they are in viable numbers and grouped in major clusters.

Better information regarding the spatial variability of height, Diameter at Breast Height (DBH) and stocking could improve inventory estimates at the operational Planning Unit since these parameters are used extensively in allometric equations, including stem volume, biomass and carbon calculations. In this study, the influence of stand stocking on height and DBH of two even aged radiata pine (Pinus radiata D. Don) stands were investigated using airborne Light Detection and Ranging (LiDAR) data at a study site in New South Wales, Australia. Both stands were characterized by irregular stocking due to patchy establishment and self-thinning in the absence of any silvicultural thinning events. For the purpose of this study, a total of 34 plots from a 34 year old site and 43 plots from a nine year old site were established, from which a total of 447 trees were sampled. Within these plots, DBH and height measurements were measured and their relationships with stocking were evaluated. LiDAR was used for height estimation as well as stem counts in fixed plots (stocking). The results showed a significant relationship between stem DBH and stocking. At both locations, trees with larger diameters were found on lower stocking sites. Height values were also significantly correlated with stocking, with taller trees associated with high stocking. These results were further verified of additional tree samples, with independent field surveys for DBH and LiDAR-derived metrics for height analysis. This study confirmed the relationship between P. radiata tree heights and stem diameter with stocking and demonstrated the capacity of LiDAR to capture sub-compartment variation in these tree-level attributes.

Teak (Tectona grandis Linn. f.) is one of the most economically valuable types of tropical forest because teak wood has high durability, resilience and good aesthetic qualities. Teak tree improvement in Indonesia was initiated in 1983 producing planting stock for reforestation, i.e. clonal seed orchards (CSO) to produce seedling as sexual reproduction (referred to seedling), and hedge orchards to produce shoot cuttings as asexual (vegetative) reproductive (referred to shoot cuttings). Teak plantations established using seedling and shoot cuttings should improve forest productivity. The objectives of this study were to compare the growth rate, wood properties, and soil fertility of teak plantations propagated using seedling and shoot cuttings. Three square plots of 100 trees (10 × 10 trees; 1,000 m2) were established on both types of plantation and tree growth characteristics, wood properties, and soil fertility were monitored. The tree growth characteristics were diameter at breast height (DBH), tree height (H), clear bole height (CB), and volume of standing stock (Vss), and the wood properties included pilodyn penetration (PP) and stress wave velocity (SWV). Soil fertility was assessed from soil samples collected from three soil depths, with three replicates in each plot: 0–5 cm (top layer), 6–30 cm (middle layer), and 31–60 cm (bottom layer). Soil samples were analysed for total nitrogen, total phosphorus, total potassium, total calcium, and total magnesium. The results showed that the mean DBH, H, CB, and Vss differed significantly between the type of planting stock. The DBH, H, CB, and Vss values were 28.4%, 46.8%, 49.1%, and 130.1% higher, respectively, in teak plantations from shoot cuttings than from seedling. Moreover, the SWV of shoot cuttings planting stock plantation was 3.6% higher than from seedling. The mean PP did not differ significantly between teak plantations from shoot cuttings (22.00 mm) and seedling (21.80 mm). Furthermore, the planting stock did not affect soil fertility, which was highest in the top layer in all treatments. Our results suggest that teak plantations from shoot cuttings would increase growth, forest productivity, maintaining wood quality and soil fertility. Thus, it can maintain sustainable teak forest plantations.

Candidate plus tree selection is considered as an important and preliminary step in tree improvement program of a particular species. Plus tree selection is the first step to improve production and quality in forestry. In present study, 85 candidates plus trees of chironji showing good phenotype have been selected from different places covering three districts of central Chhattisgarh region viz., Mahasamund, Gariyabandh and Kabirdham following comparison tree method.The tree height, DBH, clear bole height and average crown diameter varied from 6.5 m-16.5 m, 10.50 cm-40.42 cm, 1.2 m-4.0 m and 2.1m-6.8 m respectively. The highest tree height found for CPT 2 as 16.5 m in Komakhan village, Mahasamund district. The highest tree diameter at breast height (DBH) was found (CPT 2) 40.42 cm in BK Bahra village, Mahasamund district. The highest average crown diameter found was observed for CPT 14 and CPT 20 as 6.8 m in Neyur village Kabirdham district.

In this study, it was aimed to develop height (H)-diameter (D) models for pure Pinus brutia Ten. stands distributed in the Adana-Karaisalı region in Türkiye. Diameter at breast height and tree height data were obtained from 1081 sample trees in 82 sample plots. Additionally, measurements were made regarding various stand variables. Based on the data obtained, parameters were estimated for four base H-D models, which provide estimates based only on diameter at breast height, and five generalized H-D models, which incorporate stand variables in addition to diameter at breast height. According to the results of nonlinear regression analysis, models with all parameters being statistically significant were evaluated based on six statistical criteria. The ranking results showed that the Mirkovich (1958)’s generalized H-D model achieved the best predictive results, with an coefficient of determination (R²) value of 0.941, indicating that the model accounts for 94.1% of the variation in tree height and can be considered a reliable tool for estimating tree height in the studied stands. As a result of statistical and graphical evaluations, it can be concluded that generalized H-D models perform better and yield more unbiased predictions.

Direct seeding is a less expensive practice than planting and has the potential to become a viable alternative to transplanting for afforestation and regeneration purposes. As an effective and a less costly regeneration method, aerial seeding has been applied with several tree species. As early as 1956, Chinese people engaged in aerial seeding and stands with a total of 2.97×107 hm2 have been developed up to 2004. Our study tested whether the growth of planted Chinese pine (Pinus tabulaeformis Carr.) seedlings and its undergrowth development in northwest aspects differ from that of aerially sown seedlings on the northern and northwestern aspects of slopes. In 2007, we collected data such as height, diameter at breast height (DBH), clear bole height and canopy widths of trees, abundance, coverage, and frequency of shrubs and herbs from 21-year-old planted Chinese pine stands on a northwestern aspect (PNW), aerially sown stands in a northwest aspect (ANW) and aerially sown stands in a northern aspect (AN). Results showed that the relation of crown area and mean DBH was best fitted by a double inverse model for the ANW and AN forests and by a quadratic model for the PNW forest. There was no difference in the growth between ANW and AN forests, while growth was significantly higher in the PNW forest than in the ANW and AN forests. That was consistent with the Sorenson diversity indices in the shrub and herb layers, indicating that there was a large number of the same species in both aerially seeded stands, although their locations were different. Both the number of species in the undergrowth and the Shannon-Wiener index in the shrub layer were higher in the PNW stands than in the ANW and AN stands. Dominant families for all three stands were Rosaceae and Compositae in the shrub and herb layer, respectively. The dominant species for all three stands was Spiraea pubescens in the shrub layer, while the dominant species was different from each other in the three stands. The discrepancy in diversity and composition of species in the herb layer show that herbs are sensitive to shrubs in the three forests. High mortality and skewed diameter distributions reflect severe competition and too high a density in the aerially seeded forests. Thus, aerial seeding is a viable and effective regeneration technique, but management practices, such as thinning, should be applied to these forests.