Research Article |
Corresponding author: Buyanjargal Batchuluun ( buyanjargalb@mas.ac.mn ) Academic editor: Lyubomir Penev
© 2020 Buyanjargal Batchuluun, Jens Wunderlich, Michael Schmitt.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Batchuluun B, Wunderlich J, Schmitt M (2020) Diversity of beetles (Coleoptera) in natural and planted saxaul forests (Haloxylon ammodendron) in the South Gobi Desert, Mongolia. ZooKeys 1000: 59-70. https://doi.org/10.3897/zookeys.1000.56856
|
We investigated species composition and diversity parameters of beetle communities in two planted saxaul (Haloxylon ammodendron, black saxaul) forests in Southern Mongolia. We also studied nearby natural areas for comparison. Beetles were mainly collected by pitfall traps. 1064 individuals of 38 species of 22 genera in 4 beetle families were identified from planted plots. In comparison, a total of 1395 beetles belonging to 40 species of 24 genera in seven families were collected and identified from the natural saxaul plots. The most diverse beetle families were darkling beetles (Tenebrionidae, 18 species) and snout beetles (Curculionidae, 15 species) in planted and natural saxaul plots. We recorded several species (Apatophysis serricornis, Cephogenia chinensis, and Eumylada punctifera punctifera) which are associated with the saxaul tree. A darkling beetle, Anatolica potanini, was the dominant species in both natural and planted plots of the Nariin Zag forest. There were significant differences in the species richness and abundance between the planted and natural plots of the Ukhaa Zag forest. It is possible that the age of the plantation drove the differences. The higher values of diversity indices and species richness in the planted plots can be explained by the presence of rare species, represented by only one or two individuals. The planted plots and corresponding natural plots within each forest were more similar to each other in species composition and abundance than between forests.
Beetle community, black saxaul, species richness
Beetles constitute the main component of insect communities in arid landscapes. They inhabit these landscapes in close interaction with plants, using them as food resources, for shelter, and as development sites. Beetles are regarded to be indicators of environmental changes (e.g.,
Insect biodiversity studies in arid regions of Mongolia have a goal of understanding the current state of the ecosystem, which suffers from the pressure of human activities, including livestock overgrazing and mining operations. Climate change is an additional stress factor, as it is occurring at a much higher rate in Mongolia than the global average, particularly in the Gobi Region (
Restoration success of natural habitats can be evaluated using their beetle communities as indicators of overall habitat quality (
The purpose of the present study is to investigate the diversity of the beetle community in natural and planted the saxaul forests and to identify whether or not planted forests support the natural beetle community.
The study was carried out in the Umnugovi Aimag, the South Gobi province of Mongolia. The climate of the area is typically continental with cool spring and autumn, warm dry summer, and cold winter. The average maximum temperature in July is 31.1 °C; the average minimum temperature in December and January is −15.0 °C. The average annual total precipitation is 97 mm, and the average number of annual rainfall days is 32 days (averaged from the nearby “Khanbogd” weather station, using data from 1976–2014). According to the classification of phytogeographical regions of Mongolia, the study area belongs to the desert steppe of the East Gobi Region (
In accordance with the environmental rehabilitation and offset programs of Oyu Tolgoi Limited Liability Company (LLC), the biggest copper mining company in the south Gobi province of Mongolia, saplings of Haloxylon ammodendron (black saxaul) were planted in two different saxaul forests:
We set 15 pitfall traps in each plot along a line. The distance between the traps was 10 m. The sampling interval was 7 days and traps were active 24 hours a day for each sampling interval. We used empty pitfall traps to avoid attracting animals by water. In addition to the pitfall traps, we beat and shook 10 saxaul trees every 14 days for plant dwelling beetles and subsequently searched the sand under the trees.
Sampling was carried out during the plant growing season from June to September in 2019. Beetles were preserved in 70% ethyl alcohol and were subsequently transported for further processing and species identification to the Laboratory of Entomology, Institute of Biology, Mongolian Academy of Sciences (
Observed species richness (Mao Tau), Pielou’s evenness index, and Shannon and Simpson diversity indices were used as diversity parameters. Paired T-tests were used to compare beetle diversity, species richness, and abundance differences between natural and planted plots. We calculated a Bray-Curtis index for cluster analysis. Diversity and similarity analyses were done by EstimateS 9.1.0 and paired T-tests calculated in Minitab Stat 15. Significance level was 0.05.
Beetles from the tree shaking samples were not analysed statistically, only searched for additional species. The distribution range analysis was done for captured species using an approach in
A total of 3,349 beetles belonging to 48 species of 30 genera in eight families were identified from natural and planted saxaul plots. Therein, 1,395 beetles belonging to 40 species were collected and identified from natural saxaul plots and 1,064 individuals of 38 species were identified from planted plots (Appendix
According to the distribution range analysis, the majority of species (17 species, 37.0%) are distributed only in northern China and southern Mongolia, and eight species (17.4%) are endemic to Mongolia. Other species have a wider range from Kazakhstan to southern China (4.3%), southern Siberia, and Mongolia (8.7%), and from southern Siberia to northern China (10.9%), and Eurasia (21.7%). The most diverse beetle families were darkling beetles (Tenebrionidae, 18 species) and weevils (Curculionidae, 15 species) in planted and natural saxaul plots. There were three families (Cerambycidae, Histeridae, Trogidae) in the natural plots that were not collected in the planted plots.
The observed species richness at natural saxaul plots ranged from 19 to 24 beetle species, whereas at the planted saxaul plots it ranged from 20 to 22 species (Fig.
Seven to eight species in the natural plots and 10 to 11 species in the planted saxaul plots were represented by only one or two individuals (Table
The dominance of Anatolica potanini at the plots in the Nariin Zag forest influenced the diversity index values and evenness of the plots. Therefore, species diversity and evenness at the plots were lower than at the Ukhaa Zag site. We observed significant differences in species diversity at planted and natural saxaul plots (Table
Species composition of the beetle communities showed a dissimilarity (Fig.
Diversity parameters of beetle communities in planted and natural saxaul sites.
Sites | Plots | Singletons Mean | Doubletons Mean | Shannon index | Simpson index | Evenness | T-test, p value* |
---|---|---|---|---|---|---|---|
NZ Plot 1 | Planted | 4 | 6 | 1.55 | 2.34 | 0.50 | 6.94 |
Natural | 8 | 0 | 1.52 | 2.33 | 0.47 | p = 0.000 | |
NZ Plot 2 | Planted | 8 | 3 | 1.75 | 3.12 | 0.56 | −17.71 |
Natural | 6 | 1 | 1.58 | 2.66 | 0.53 | p = 0.000 | |
UZ Plot 1 | Planted | 9 | 1 | 2.50 | 8.900 | 0.80 | −2.77 |
Natural | 6 | 2 | 2.34 | 6.93 | 0.74 | p = 0.020 | |
UZ Plot 2 | Planted | 10 | 1 | 2.08 | 4.87 | 0.69 | 3.52 |
Natural | 8 | 0 | 2.32 | 7.50 | 0.76 | p = 0.008 |
Natural saxaul (Haloxylon ammodendron, black saxaul) forests in the Gobi Desert provide and sustain several beetle species associated with the tree and its environment. In our study, we found several of these species, including a long-horn beetle, Apatophysis serricornis (Gebler, 1843), which is known to feed on generative organs and roots of saxaul in desert areas of south-eastern Kazakhstan (
A particular surprise was the complete absence of leaf beetles (Chrysomelidae) in our samples.
The guild of herbivorous Coleoptera is well represented by the numerous weevil species (Appendix
The total beetle abundance of the Ukhaa Zag plots is clearly lower than that of the Nariin Zag site. Although there is no absolute dominant species in the Ukhaa Zag plots, two darkling beetle species, Microdera globata (Faldermann, 1835) and Anatolica amoenula Reitter, 1889, were relatively highly abundant in both planted and natural plots. The genus Microdera is known as a geochortobiont living in surface soil and specializes in climbing up plants to eat seeds (
There was no significant difference between beetle species richness and abundance of planted and natural saxaul plots in the Nariin Zag habitat. This could be explained by the proximity of the planted plots, which were situated within the natural forest (Fig.
The higher values of diversity indices and species richness in the planted plots are driven by the presence of rare species, represented by only one or two individuals. However, a positive effect of reforestation on species richness of ground beetles was also observed, indicating that the creation of the pioneer habitats is important for successful reforestation (
In summary, restored saxaul forests (Haloxylon ammodendron) in the Gobi Desert are capable of supporting a natural beetle community composed mainly of species of Tenebrionidae and Curculionidae and characterised by a high level of endemism. Therefore, rehabilitation of saxaul, a native and a key plant species, is an important effort to conserve Gobi’s natural state and its living components. Our study is the first effort to evaluate the success of the saxaul rehabilitation programme in Mongolia using a beetle community.
This research was supported by the Michael Succow Foundation (MSF) and the University of Greifswald under their joint project “Central Asian Desert Initiative” (CADI), which is funded by the German Ministry of Environment, Nature Conservation, and Nuclear Safety under the International Climate Initiative (IKI). For constructive reviews, we also thank Dr Gantigmaa Chuluunbaatar, Laboratory of Entomology, Institute of Biology,
List of beetle species of natural and planted saxaul forests in the South Gobi Desert, Mongolia.
Species | Nariin Zag | Ukhaa Zag | ||
---|---|---|---|---|
Natural | Planted | Natural | Planted | |
Carabidae | Specimens (captured by pitfall traps) | |||
Cymindis binotata Fischer von Waldheim, 1820 | 2 | |||
Cymindis semenowi Jakovlev, 1889 | 26 | 43 | 4 | 2 |
Harpalus amplicollis Ménétriés, 1848 | 8 | 2 | 2 | 1 |
Harpalus viridanus Motschulsky, 1844 | 1 | 1 | ||
Pseudotaphoxenus dauricus dauricus (Fischer von Waldheim, 1823) | 1 | |||
Cerambycidae | ||||
Apatophysis serricornis (Gebler, 1843) | 1 | |||
Curculionidae | ||||
Adosomus albisquama Ter-Minasian, 1976 | 1 | |||
Baris kiritshenkoi Zaslavskij, 1956 | 1 | |||
Conorhynchus pulverulentus (Zoubkoff, 1829) | 4 | 1 | 19 | 9 |
Deracanthus faldermanni (Faldermann, 1835) | 3 | 2 | 17 | 17 |
Deracanthus hololeucus (Faldermann, 1835) | 3 | 6 | ||
Deracanthus jakovlevi jakovlevi Suvorov, 1908 | 6 | 2 | 4 | 2 |
Deracanthus pallasi Faust, 1890 | 1 | 1 | ||
Deracanthus pulchellus Gyllenhal, 1840 | 4 | 2 | 1 | |
Deracanthus sibericus (Thunberg, 1799) | 10 | 6 | 4 | |
Megamecus variegatus (Gebler, 1830) | 12 | 6 | ||
Metadonus distinguendus (Boheman, 1842) | 1 | |||
Stephanocleonus gemellus Voss, 1967 | 1 | 1 | ||
Stephanocleonus gobianus Suvorov, 1912 | 3 | 4 | 33 | 7 |
Stephanocleonus incertus Ter-Minasian, 1972 | 1 | 1 | 2 | |
Temnorhinus oryx (Reitter, I897) | 3 | |||
Geotrupidae | ||||
Lethrus potanini Jakovlev, 1889 | 6 | 10 | ||
Histeridae | ||||
Saprinus sp. 1 | 1 | |||
Saprinus sp. 2 | 1 | |||
Scarabaeidae | ||||
Aphodius fasciatus (Olivier, 1789) | 1 | 7 | ||
Cetonia aurata (Linnaeus, 1761) | 1 | |||
Cheironitis eumenes (Gebler, 1860) | 1 | |||
Brahmina agnella agnella (Faldermann, 1835) | 1 | |||
Psammodius asper (Fabricius, 1775) | 5 | 1 | ||
Tenebrionidae | ||||
Anatolica amoena (Faldermann, 1835) | 25 | 37 | ||
Anatolica amoenula Reitter, 1889 | 24 | 37 | 115 | 44 |
Anatolica mucronata Reitter, 1889 | 8 | 12 | ||
Anatolica nureti Schuster & Reymond, 1937 | 104 | 60 | 7 | 3 |
Anatolica potanini Reitter, 1889 | 588 | 485 | 7 | 2 |
Anatolica pusilla Kaszab, 1967 | 1 | |||
Anatolica sternalis gobiensis Kaszab, 1964 | 4 | |||
Blaps femoralis rectispina Kaszab, 1968 | 12 | 13 | 60 | 30 |
Blaps miliaria Fischer von Waldheim, 1844 | 11 | 8 | ||
Centorus calcaroides gobiensis (Kaszab, 1964) | 5 | 1 | ||
Cyphogenia chinensis (Faldermann, 1835) | 4 | 2 | ||
Eumylada punctifera punctifera (Reitter, 1889)* | ||||
Melanesthes csikii Kaszab, 1965 | 1 | 7 | 6 | |
Melanesthes parvula Kaszab, 1967 | 1 | 1 | 1 | |
Microdera globata (Faldermann, 1835) | 22 | 30 | 84 | 72 |
Platyope mongolica Faldermann, 1835 | 8 | 11 | 32 | 9 |
Pterocoma reitteri Frivaldszky, 1889 | 6 | 5 | ||
Sternotrigon grandis (Faldermann, 1835) (= S. mongolica Reitter, 1889) | 36 | 13 | 12 | |
Trogidae | ||||
Trox cadaverinus Illiger, 1802 | 1 |