The Success of Root Cuttings is Endangered Kalapi (Kalappia celebica Kosterm.) by Giving Rootone-F Growth Regulator

Kalapi (Kalappia celebica Kosterm.) is endemic in Sulawesi and Endangered species. Plant propagation needs to be done but is constrained by limited seeds. Vegetative propagation of plants can be an alternative method such as using the root cutting technique that has been done previously on other types of species. This study aims to determine the success of vegetative propagation of kalapi (K. celebica), an endangered tree species by root cuttings using Rootone F. as root growth regulator. The research took place from March to June 2019 conducted at the plastic house of the Indonesian Mycorrhizal Association (AMI) Southeast Sulawesi Branch, Kendari. This study used a Randomized Block Design (RBD) consisting of 6 treatments of Rootone-F concentration : (a) 0 ppm, (b) 100 ppm, (c) 200 ppm, (d) 300 ppm, (e) 400 ppm and (f) 500 ppm. Each treatment was repeated three times and three units of the plant so that the total experimental unit used was 54 units. The results showed that the provision of Rootone-F could increase the success of the growth of kalapi root cuttings. Rootone-F concentration of 500 ppm gives the best results on the percentage of cuttings, percentage of sprouts, percentage of roots, number of shoots and shoot dry weight. The results showed that kalapi can be propagated by root cuttings.

Machine Learning Classification of Endangered Tree Species in a Tropical Submontane Forest Using WorldView-2 Multispectral Satellite Imagery and Imbalanced Dataset

Accurate maps of the spatial distribution of tropical tree species provide valuable insights for ecologists and forest management. The discrimination of tree species for economic, ecological, and technical reasons is usually necessary for achieving promising results in tree species mapping. Most of the data used in tree species mapping normally have some degree of imbalance. This study aimed to assess the effects of imbalanced data in identifying and mapping trees species under threat in a selectively logged sub-montane heterogeneous tropical forest using random forest (RF) and support vector machine with radial basis function (RBF-SVM) kernel classifiers and WorldView-2 multispectral imagery. For comparison purposes, the original imbalanced dataset was standardized using three data sampling techniques: oversampling, undersampling, and combined oversampling and undersampling techniques in R. The combined oversampling and undersampling technique produced the best results: F1-scores of 68.56 ± 2.6% for RF and 64.64 ± 3.4% for SVM. The balanced dataset recorded improved classification accuracy compared to the original imbalanced dataset. This research observed that more separable classes recorded higher F1-scores. Among the species, Syzygium guineense and Zanthoxylum gilletii were the most accurately mapped whereas Newtonia buchananii was the least accurately mapped. The most important spectral bands with the ability to detect and distinguish between tree species as measured by random forest classifier, were the Red, Red Edge, Near Infrared 1, and Near Infrared 2.

IMPACT OF NATURAL ENEMIES ON LARVAE OF THAUMETOPOEA BONJEANI (LEPIDOPTERA NOTODONTIDAE) IN ASSOCIATION WITH THAUMETOPOEA PITYOCAMPA IN NORTHERN ALGERIA

The cedar processionary moth, Thaumetopoea bonjeani (Lepidoptera: Notodontidae), is a serious pest of the Atlas cedar Cedrus atlantica in north-western Africa and it is involved in the decline of this endangered tree species. Natural enemies of the cedar processionary moth are poorly known, especially for parasitoids, predators and pathogens of the larval-pupal life stages. Mature larvae were collected and examined in 2014 and 2015 in natural stands of Atlas cedar in the Djurdjura (northern Algeria), in occurrence with pine processionary moth Thaumetopoea pityocampa. The overall mortality rate of larvae of Thaumetopoea bonjeani ranged from 26.4% to 31.1%, with generalist predators and parasitoids being more effective than pathogens. Four primary parasitoid species were recorded, of which four tachinid flies and one braconid wasp, as well as four predatory beetles and one fungus. The most important species were the carabid Calosoma sycophanta and the tachinid Compsilura concinnata. The cooccurrence of T. bonjeani and T. pityocampa may offer to generalist natural enemies an extended period of availa- bility of similar preys, as the two processionary moths have different life cycles. The sharing of natural enemies between the two species of Thaumetopoea can mitigate the outbreaks of both species.

Spatial distribution patterns of Afzelia africana (Fabaceae – Detarioideae) in a tropical savanna of Benin: implications for management

Background and aims – Understanding the spatial patterns and associations of tree species with their conspecific and heterospecific neighbours is critical for sustainable management of their stands. This study assessed the intra- and interspecific spatial structure of six life stages in Afzelia africana, a keystone multipurpose and endangered tree species in a tropical savanna of Benin.Material and methods – Three plots of 4 ha each were demarcated on three sites along a conservation gradient (hunting zone – core conservation zone). Individuals of A. africana (irrespective of their diameter at breast height) and heterospecific trees (dbh ≥ 5 cm) were mapped. Tree spatial patterns and associations were determined using univariate and bivariate pair correlation functions. The distance to the nearest neighbour was further used to assess tree-to-tree distance.Key results – We found variable spatial patterns across sites. In the core zone where wildlife density is high, most life stages had a random distribution. In contrast, in the hunting zone where wildlife density is low, the species spatial distribution changed from a predominantly aggregative pattern during early stages to a less aggregative or random spatial pattern for very large adults. Most pairs of life stages showed neutral associations, except for small and large adults, which had positive association between themselves on two sites. We also found that A. africana tree spatial distribution was unrelated to heterospecific trees.Conclusion – We suggest that bush fire, seed dispersion, predation, and local environment would have contributed to the observed patterns.

Ontogenetic niche shifts in a locally endangered tree species (Olea europaea subsp. cuspidata) in a disturbed forest in Northern Ethiopia: Implications for conservation

Understanding the responses of different ontogenetic stages to environmental and human disturbance factors is essential for developing efficient conservation strategies for endangered plant species. We examined how three ontogenetic stages of a locally endangered tree species, Olea europaea subsp. cuspidata, responded to environmental factors and human disturbance in Hugumburda dry Afromontane forest in Ethiopia. We counted individual seedlings, saplings and adults of O. europaea in 70 20 × 20 m quadrats over ca. 2.8 ha, and measured biotic (woody species richness, canopy cover, aboveground tree biomass, herbaceous cover), abiotic (soil and topographic variables), and human disturbance factors (logging and tracks). To detect ontogenetic niche shifts, we compared observed vs. simulated locations of trees in the three life stages and how they related to the environmental and human disturbance factors. We found that the population structure of O. europaea showed generally low recruitment, with few seedlings per hectare compared with the abundance of saplings and adults. The probability of finding O. europaea individuals was influenced by biotic (woody species richness) and abiotic (soil depth, slope) environmental conditions and human disturbance (logging intensity), but the direction, strength and shape of the relationships differed between seedling, sapling and adult life stages, indicating ontogenetic niche shifts. All life stages showed a positive relationship with elevation. The observed environmental niches of the different lifestages of O. europaea, and their association with human disturbance levels, should be considered when conservation strategies are developed for this species. Human disturbance in terms of logging decreases the abundance of saplings, but may facilitate emerging seedlings through creation of gaps with improved light conditions. Recruitment is, however, very low in the study area, and seedlings should be protected from browsing to enhance survival. Woody species richness in general should be conserved to optimize conditions also for O. europaea saplings.

Structural diversity and conservation implications of Parrotia subaequalis (Hamamelidaceae), a rare and endangered tree species in China

Parrotia subaequalis (H. T. Chang) R.M. Hao & H.T. Wei is a rare and endangered Tertiary relict tree that is endemic to subtropical China. However, little is known about its growth condition and relationship with associated tree species. Here, for the first time we measured the structural diversity of P. subaequalis communities at three representative sites in eastern China using four structural indices, including mingling, tree-tree distance, and diameter and tree height differences. The results showed that: 1) Collectively, most P. subaequalis and associated tree species were small and mid-sized classes in tree height, and small-sized class in diameter; 2) There were two or more other tree species around most of P. subaequalis individuals across the three sites; 3) Overall, the mean distance between reference trees and their neighbors was mainly 1–2 m. Our results indicated that a strong interspecific competition existed between P. subaequalis and its associated tree species. Meanwhile, although the reference tree P. subaequalis had slight advantages in both horizontal and vertical planes, we think that it is necessary to take some effective measures to reduce the interspecific competition and thereby keep it at a proper successive stage. In addition, we also discuss the protection level of P. subaequalis in China, and propose to keep this species at the First-Grade State Protection.

Study on the Genetic Structure Based on Geographic Populations of the Endangered Tree Species: Liriodendron chinense

Liriodendron chinense (Hemsley) Sargent is a Class II protected plant in China as natural populations are on the verge of extinction. There is still a lack of systematic research on the genetic resources of its geographic populations. In this study, we used 20 pairs of SSR markers with high polymorphism to analyze a total of 808 L. chinense samples from 22 regions, and 63 Liriodendron tulipifera Linn samples from 2 regions were used as a comparison group. The results revealed a total of 78 alleles in L. chinense, and the average expected heterozygosity (He) was 0.558, showing a low level of genetic diversity. The degree of differentiation of L. chinense was high, with the differentiation coefficient (Fst) as high as 0.302, which is related to the low gene flow (Nm = 0.578). Based on the genetic structure, principal coordinate analysis (PCoA) and phylogenetic analysis of 24 Liriodendron spp. populations, L. chinense and L. tulipifera had obvious differentiation, while the differentiation between L. chinense geographic populations was very large and irregular. Inbreeding appears within the geographic populations, and the level of genetic diversity is very low. In order to protect the genetic diversity of L. chinense, in addition to protecting the existing population as much as possible, artificial cultivation should introduce materials from multiple populations.