Species Diversity and Decorative Features of Plants Used in the Landscaping of Hanoi

The article presents the results of studies on species diversity and decorative features of plantations in Hanoi. The relevance of this research is justified by the failure to meet the standards of landscaping in the city in accordance with global recommendations and standards. The dendroflora of central Hanoi has 304 species (including varieties and forms) belonging to 253 genera and 104 families. The leading families are Fabaceae, Arecaceae, Asteraceae, Apocynaceae, Bignoniaceae, Meliaceae, Verbenaceae, Myrtaceae, Moraceae, Caesalpiniaceae, Rosaceae, and Magnoliaceae. The Fabaceae family predominates by the the number of genera and species; and is followed by the Moraceae family. The greatest species diversity is observed among trees (151 species – 49.67 % of the total number). The most commonly used species in the urban gardening are Peltophorum pterocarpum, Delonix regia, Khaya senegalensis, Chukrasia tabularis, Ceiba pentandra, Pterocarpus macrocarpus, Hopea odorata, Dracontomelon mangiferum, Alstonia scholaris, Lagerstroemia speciosa, and Terminalia mantaly. Evergreen species predominate among plantations of Hanoi; while deciduous (including shrubs and trees) have a smaller proportion. Of 151 species of trees, 70 are classified as decorative. Shrubs and herbs are inferior to trees by the number of species (58 species each – 19.08 %). Palm trees are the least numerous – 11 species (3.62 %). The decorative features of the main species have been determined. A list of trees with 3 or more decorative features, shrubs and herbs with 2 or more decorative features was compiled. In order to create a unique urban landscape in different seasons of the year it is recommended to use the species included in this list. For citation: Nguyen Thi Yen, Dang Van Ha, Parinova T.A. Species Diversity and Decorative Features of Plants Used in Landscaping of Hanoi. Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 5, pp. 65–75. DOI: 10.37482/0536-1036-2021-5-65-75

Effects of Perennial Intercrops on Oil Palm Agronomic and Yield Traits

Background: Intercropping is wildly practiced in oil palm plantation in Thailand for a long time. However, there are few studies connected to oil palm intercropping. This study evaluated the effects of perennial intercrops on the agronomic and yield traits of oil palm.Methods: The observation used a completely randomized design with eight treatments including oil palm monocropping, oil palm intercropped with Intsia palembanica, Hopea odorata, Swietenia macrophylla, Ternstroemia wallichiana, Azardirachta excelsa, Magnolia champaca and Mesua ferrea. The height and stem perimeter of intercrops were recorded as were the plant height and diameter, number of male and female inflorescences and sex ratio of the oil palms. Those parameters were observed in October 2019, February and June 2020.Result: Oil palm intercropped with A. excelsa produced the highest number of female inflorescences and oil palm intercropped with M. champaca produced the highest sex ratio in October 2019 and February 2020, however, the differences of those parameters were not found in June 2020. There were no significant differences in the diameter, height, the number of male inflorescences throughout the observation. Among the 7 intercrops, M. champaca and A. excelsa produced the highest growth rate of plant height and stem perimeter, respectively. In conclusion, oil palm can be intercropped with perennial plants. However, more research is needed to determine the long-term effects of intercropping in oil palm.

Stem borer insects on Hopea odorata in Bogor, West Java, Indonesia

Haneda NF, Furqan M, Suheri M. 2020. Stem borer insects on Hopea odorata in Bogor, West Java, Indonesia. Biodiversitas 21: 5308-5316. Hopea odorata Roxb. locally known as “merawan”, is a dipterocarp species that has the potentials to be developed for plantation forestry. Nonetheless, anecdotal evidence in Bogor, West Java, Indonesia, suggested that the trees suffered serious attacks caused by stem borer insects, causing defoliation of the crown and leading to stunted growth and death. This phenomenon suggests a more systematic investigation. The objectives of this research were: (i) to identify the species of stem borer which attacked H. odorata; (ii) to investigate the types and forms of the damage of H. odorata tree due to stem borer attack; and (iii) to study the effects of stem borer attack on the tree and wood of H. odorata. The results showed that all species of stem borer insects belong to Coleoptera, namely as Xyleborus perforans (Scolytidae), Xyleborinus perexiguus (Scolytidae), Platypus parallelus (Platypodidae), Belionota prasina (Buprestidae), Curculionid beetle, and Tenebrionid beetle. The number of boring holes on a single tree was 1932 holes, of which 98.6% caused by ambrosia beetles: Xyleborus perforans (1426 holes, 73.8%), Xyleborinus perexiguus (457 holes, 23.7%), and Platypus parallelus (21 holes, 1.1%). The length of boring tunnel at cross-section ranged between 2-35 cm and at longitudinal section ranged between 4-6 cm. The number of boring holes decreased along with the increasing height of tree stem. The patterns of boring tunnel at stem cross-section were branching (X. perforans, P. parallelus); encircled (X. perforans), black stains along their wall (X. perexiguus, X. perforans, P. parallelus).

Maximum entropy modeling for the conservation of Hopea odorata in riparian forests, central Thailand

Asanok L, Kamyo T, Marod D. 2020. Maximum entropy modeling for the conservation of Hopea odorata in riparian forests, central Thailand. Biodiversitas 21: 4663-4670. Hopea odorata plays a dominant role in both ecologically and economically in Thailand. We analyzed potentially suitable areas for H. odorata in the riparian zone of the Chao Phraya River using the software MaxEnt. Modeling included 164 occurrence records along with 19 climate-related variables, slope, aspect, and elevation. Precipitation was the key climatic variable influencing the distribution of H. odorata. Riparian areas along the Chao Phraya that were predicted to be highly suitable for this species were located in the provinces of Nakhon Sawan, Ang Thong, Phra Nakhon Si Ayutthaya, Pathum Thani, Nonthaburi, and Bangkok. The ROC AUC score was 0.891, indicating that MaxEnt is an excellent tool for predicting suitable regions for the restoration or cultivation of commercially and ecologically valuable species such as H. odorata. Models such as what we have presented here can facilitate habitat conservation and sustainable resource use for rare and important plants.