Population genetics and ecology of Sumatran camphor (Dryobalanops aromatica) in natural and community-owned forests in Indonesia

Ritonga FN, Dwiyanti FG, Kusmana C, Siregar UJ, Siregar IZ. 2018. Population genetics and ecology of Sumatran camphor (Dryobalanops aromatica) in natural and community-owned forests in Indonesia. Biodiversitas 19: 2175-2182. Dryobalanops aromatica Gaertn. f. (Sumatran camphor) is a valuable tree species that produces borneol (camphor) and good-quality timber. However, the population of this species has declined due to illegal logging and conversion of forests into plantations and has been classified as Critically Endangered by the International Union for Conservation of Nature. This study aimed to examine the genetic variation and spatial distribution of this species in a community-owned forest (Barus) and two natural forests (Singkohor and Danau Paris) in Indonesia using the Random Amplified Polymorphic DNA marker. The results of this study showed that D. aromatica had moderate levels of genetic variation (expected heterozygosity [He] = 0.1760 [Barus population] to 0.2134 [Singkohor population]) and genetic differentiation (Nei’s Gst = 0.1257). The genetic distance was the smallest between the Singkohor and Danau Paris populations (Nei’s distance = 0.0363) and greatest between the Singkohor and Barus populations (Nei’s distance = 0.0534). The spatial distribution of D. aromatica was grouped in both Barus and Danau Paris based on Morisita’s index of diversity (ip = 0.06 and 0.043, respectively). These findings indicated that genetic conservation might be performed in situ in combination with enrichment planting using locally propagated sources.

Population structure, distribution pattern and microhabitat characteristics of Aglaonema simplex in Pasatan Protected Forest, Jembrana, Bali, Indonesia

Lestari D, Asih NPS. 2017. Population structure, distribution pattern and microhabitat characteristics of Aglaonema simplex in Pasatan Protected Forest, Jembrana, Bali, Indonesia. Biodiversitas 18: 1663-1668. Aglaonema simplex Blume is one species of Aglaonema that is distributed in Bali, Indonesia. This species can be found in the forests of Jembrana, Karangasem, Tabanan, Buleleng and Bangli. There is no recent data for A. simplex’s population and microhabitat in Bali, while this data is needed to develop future conservation policy. By tracking populations over time, ecologists can see how these populations have changed and may be able to predict how they are likely to change in the future. Monitoring the size and structure of populations can also help ecologists to manage populations. This study was aimed to determine the current condition of A. simplex in the Pasatan forest and to find out the population structure, distribution, and its microhabitat characteristics. The study was conducted along two tracks at Pasatan Forest, Bali on June 9- 11, 2015. Data were collected using the purposive quadrant plot method and analyzed descriptively, tabulated in tables and graphs. The population pattern distribution was as defined by standardized Morisita's index and microhabitat differences in both tracks were determined by the Mann-Whitney test in SPSS 16. The total number of A. simplex was 114 individuals. Thirty-seven percent of plants were juveniles, while 36% were mature plants without fruit and 27% were mature plants with fruit. The population structure along the first track was dominated by a mature population of plants without fruit, while fruiting mature plants dominated the structure of the population along the second track. The distribution of the population along the first track was clustered, while distribution along the second track was uniform. A. simplex was found at an altitude of 367- 448 m asl., oil pH of 6.7-6.8, soil humidity of 73%-84%, air temperature 27°-28° C, air humidity at 80%-86%, with low light intensity of 170-225 lux.

Demographics and spatial pattern on three populations of Myrtaceae in the Ombrophilous Mixed Forest

ABSTRACT: The aim of this study was to characterize the demographic structure and spatial pattern of Campomanesia xanthocarpa (Mart.) O. Berg, Myrcianthes gigantea (D. Legrand) D. Legrand and Myrciaria delicatula (DC.) O. Berg. Within one hectare of Ombrophilous Mixed Forest, all the three populations' individuals were counted and measured with regard to their height and diameter. From the collected data, the assessment of the demographic structure was realized after the individual's size classification. Spatial pattern was determined by applying the Standardized Morisita's Index. C. xanthocarpa and M. delicatula showed an inverted-J frequency distribution in the individuals size classes, which differed from M. gigantea that did not follow the same pattern. The spatial pattern of C. xanthocarpa and M. delicatula populations was found mainly to be aggregated; whereas, M. gigantea showed spatial randomness. The three Myrtaceae populations responded differently with regard to structure and spatial distribution in sites with the same environmental filters.

Effects of Host Physiology on the Development of Core Rot, Caused by Alternaria alternata, in Red Delicious Apples

Alternaria alternata is the predominant fungus involved in moldy core and core rot of Red Delicious apples. The effects of environmental conditions during bloom on moldy core and core rot, and on the need for fungicide application, were examined in 10 experiments carried out in 2007. In untreated experimental plots, typical moldy core symptoms were very common, with relatively low variability (coefficient of variation: 22.2%) among experiments; core rot incidence ranged from 2 to 26% with large variability (coefficient of variation: 90.0%) among experiments. No evidence of prevailing environmental conditions during bloom affecting the development of moldy core or core rot was detected. No effect of fungicide application (a mixture of bromuconazole + captan three times a week at bloom) on moldy core or core rot was found. A random distribution of moldy core and an occasional aggregation of core rot in the orchards were indicated from Morisita's index of dispersion (Iδ). The hypothesis that core rot incidence is governed by host physiology and that yield load can be used as an indicator of trees' susceptibility was examined in a set of eight observations and four experiments. No correlation was found between tree yield load and moldy core, but core rot incidence was inversely related to yield load. Furthermore, irrespective of tree yield load, core rot was more abundant on large compared with small fruits. It is concluded that host physiology, rather than pathogen occurrence or environmental conditions at bloom stage, governs the development of core rot in Red Delicious apples caused by A. alternata in Israel.

Food habits of feral cats (Felis silvestris catus L.) in insular semiarid environments (Fuerteventura, Canary Islands)

In this study, we present the first data on diet and impacts of feral cats on a semiarid island (Fuerteventura, Canary Islands). A total of 614 prey was identified in the 209 scats analysed. Introduced mammals, especially rabbits and mice, were the most consumed vertebrate prey and constituted more than 90% of biomass. Barbary ground squirrels, Algerian hedgehogs, and rats were preyed upon less even though they were abundant on the island. Invertebrates, mainly Orthoptera, Coleoptera, Hymenoptera and Odonata, were the second most important prey items (in terms of actual numbers) but they contributed only minimally with respect to biomass (<1.1%). The presence of terrestrial molluscs in the diet was interesting because they are a rare prey in an insular context. Birds and reptiles occurred at a low frequency. A total of 677 seeds was counted, mainly belonging to Lycium intricatum (Solanaceae) and two unidentified plant species. Levin’s niche breadth was narrow due to the high consumption of mammals. Morisita’s index showed a similar trophic overlap in diet with respect to the other xeric habitats of the Canarian archipelago. Considering that more than 90% of biomass corresponded to introduced mammals, we conclude that feral cats are not having a large direct impact on the native prey species.

Ordinating tropical moth ensembles from an elevational gradient: a comparison of common methods

The analysis of beta diversity (inter-habitat diversity) of very species-rich and incompletely sampled tropical arthropod communities requires the choice of appropriate statistical tools. The performance of the three commonly employed ordination methods, correspondence analysis (CA), detrended correspondence analysis (DCA), and non-metric multidimensional scaling (NMDS), was compared on a large empirical data set of geometrid moths sampled along an altitudinal gradient in an Andean montane rain forest. Despite the high species richness and incompleteness of the ensembles, all methods depicted the same, readily interpretable patterns. Both CA and NMDS showed an arch-like structure, which hints at an underlying coenocline, whereas this arch was computationally eliminated in DCA. For this particular data set, CA and NMDS both provided convincing results while the detrending algorithm of DCA did not improve the interpretability of the data. Of the large number of similarity indices available to be used in combination with NMDS, the binary Sørensen and the abundance-based Normalized Expected Species Shared (NESS) index were tested. Performance of the indices was measured by comparing stress, a measure of poorness-of-fit in NMDS. NMDS ordinations with lowest values of stress were achieved by the NESS index with the parameter m set to its maximum (mmax). In contrast, ordinations based on NESS values with the parameter m set to 1 (identical with Morisita's index), had consistently higher stress values and performed worse than ordinations using Sørensen's index. Hence, if high values of m can be achieved in similar data sets, the NESS index with mmax is recommended for ordination purposes and Morisita's index should be avoided.

Distribution of microfungi in the transitional zone of a subtropical lake in India

Counts of CFU of microfungi, percent carbon, nitrogen, phosphorus, sodium, potassium, and calcium content, and pH were determined in upland, transect, and bottom soils, the transitional zone of Gujar Lake, a subtropical and eutrophic lake in India (25°58′N, 82°39′E). Microfungi in all zones were distributed in aggregate pattern, as evidenced by significant t values (P > 0.001) and F ratios (P > 0.001) of the variance–mean test and Morisita's index. A qualitative survey revealed that Alysidium sp., Arthrinium phaeospermum, Gliomastix murorum, Pythium sp., Tliermomyces sp., Thielavia terricola, Westerdykella multispora, and Varicosporium elodae were found specific to bottom soil of the lake. Key words: distribution, microfungi, transitional zone, subtropical, correlation.