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Biodiversity, Agriculture and Culture of Taiwan Summer Program 2014
The Impact of Altitude to
the Distribution of Soil Organisms
Nicolette Lee, Priscilla Pham, Guangyan Song, Xinyue Wang, Yeo Wen Chang
1. INTRODUCTION
In the Xitou Experimental Forest, the altitude varies from 800m to 2025m1. It consists of
many types of soils, including clay, sandy soil, sandstone and gravel2. The complex
topography provides a suitable environment for our study. Based on various research
1
Environmental Factor of Xitou Natural Education Area,
http://www.exfo.ntu.edu.tw/sitou/eng/01about/default.aspx#03
2
Geology & Soil of The Experimental Forest,
http://www.exfo.ntu.edu.tw/eng/01introduction/default.aspx?id=A18DE0DF-DB38-4D03-9C8F-
47810E9A19C2

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papers, temperature, vegetation type, pH, soil type and soil depth are the most vital
factors which influence the soil composition which in turn influence the types and
amount of soil organisms3. In addition, many studies had been conducted for the
change in elevation to the number of organisms. However, there are conflicts in the
results of the studies. Besides that, most of the research are conducted in overseas
instead of Taiwan which may not appropriate and applicable in local. For example,
according to research done by H. Faoro, A.C Alves, E.M Souza4, it proved that there is
a positive correlation between change in altitude and number of organisms. In contrast,
Ma, Chen, Zhang & Wang5 claimed that the higher the altitude the lesser the bacterial
population in the cold temperate Kalasi Lake. Hence, through this research, our main
goal is to provide reliable results of soil macroinvertebrates influenced by altitudinal
elevation for Taiwan based on the foundation of these studies. In the Xitou Experiment
Forest, there are mainly two types of tree species which are Cryptomeria Japonica and
Taiwania cryptomerioides. Due to the large amount of plantation of the species,
Cryptomeria Japonica is chosen as the data collection site. Hence, this study is
conducted to investigate the impact of altitude on the number of organisms in the soil
surrounding Cryptomeria Japonica growing at different heights. The hypothesis is given
that high-altitude samples should have a greater number of organisms present in the
soil, compared to low altitudinal soils.
2. METHOD
Study sites
Three sites were chosen according to an altitudinal gradient from 1150 to 1800 m
above sea level, which were 1150m, 1450m and 1800m above sea level. Cryptomeria
Japonica species was selected at random for testing at each altitude. The
circumference of the selected tree was 100±10cm，measured at 1.0m above the
ground.
3
Zhang B, Liang C, He H, Zhang X (2013) Variations in Soil Microbial Communities and Residues Along
an Altitude Gradient on the Northern Slope of Changbai Mountain, China
4
H. Faoro, A. C. Alves, E. M. Souza, L. U. Rigo, L. M. Cruz,S. M. Al-Janabi, R. A. Monteiro, V. A. Baura
and F. O. Pedrosa (2010) Influence of Soil Characteristics on the Diversity of Bacteria in the Southern
Brazilian Atlantic Forest
5
Ma X, Chen T, Zhang G, Wang R (2004) Microbial community structure along an altitude gradient in
three different localities. Folia Microbiologica 49: 105–111. doi: 10.1007/bf02931382

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Materials
Materials selected to investigate inclinational influences on soil macroinvertebrate
diversity include five spades, two hoes with cultivators, one rope used for measuring the
trunk circumference, one measuring tape, 3 specimen containers for identifying different
taxonomies, two pairs of gardening gloves and one plastic tub to collect soil samples
per site.
Sampling procedure
At each site, and at 2.5m from tree trunks, three holes 25 x 25 cm in surface and
15cm depth were carefully excavated, according to the method devised by Ponge [1]. It
was cut with a Spades , with as little disturbance as possible, and the litter and soil
surrounding it were gently excavated, then the soil was set aside for sorting.For each
sample of soil, observations were made about the appearance (color, texture, or any
other characteristics of interest) of the soil and recorded. Soil was sorted by hand and
soil animals were observed by naked eye , the number and characteristic of collected
specimens were recorded.Once finished collecting data from one tree, the soil and the
organisms were returned to where they were found before moving onto the next tree.

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3. RESULTS
Site 1
Figure 1. Site 1 measurements and soil description
Table 1. Macroinvertebrate species count and abundance at site 1
Site 2

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Figure 2. Site 2 measurements and soil description
Table 2. Macroinvertebrate species count and abundance at site 2
Site 3
Figure 3. Site 3 measurements and soil description
Table 3. Macroinvertebrate species count and abundance at site 3

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4. DISCUSSION
Based on the given results there is a noticeable trend between macroinvertebrate
species abundance and increased altitude from sites 1 to sites 2, but a decrease in
species abundance at site 3. Benefactors that may have played in the amount of
species detected include soil composition at each site, increasing elevation and human
activity on the surrounding ecosystem.
At the first site, which was located at a low altitude of 1150 metres and 100 metres after
Xitou bridge, a high abundance of species was observed. Each hole a, b and c
contained a variety of different species which included earthworms, millipedes and
larvaes (table 1.). However, each hole contained sets of organisms which differed
progressively when going down the incline of the tree stump. This may be highly
influenced by the change in soil composition at each hole, where hole a contained clay
particles in comparison to holes b and c (figure 1.) Present clay particles may have
hindered a wide range of macroinvertebrates from transporting through the soil, though
the soil contained a high amount of moisture. Surrounding human interactions may have
also played part in the distribution of soil particulates and macroinvertebrates.
The second site, which was at mid-elevation of 1450 metres, a greater amount of
macroinvertebrates were observed. High abundance of 67 and total of 21 species
(figure 2.) may have been influenced by increased ground cover and isolation from

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human disturbances, as well as a change in temperature. An exception to the influx of
macroinvertebrates would be due to the discovery of an ant nest and a high count of
ants and ant larvaes. Soil composition also differed slightly at each hole, where hole b
at the highest elevation contained a larval nest and lighter brittle texture compared to
that of hole a’s darker and more dispersed texture. The overall all soil composition
would have allowed an easier environment for a wide range of macroinvertebrates.
Due to time constraints and physical limitations the third site was chosen on a steep
incline, beside a mountain road at 1800 metres. As the incline lead to an inaccessible
hill, the 2.5 metre measurements were taken at half the tree. Holes were dug in a line
and soil textures with little compact indicated the absence of larger macroinvertebrates.
Instead miniscule macroinvertebrates such as ants, spiders and mites were seen. A
major influence on the species distribution was the human disturbance of the mountain
road.Noticeable road fragments were observed In the soil composition, and the texture
was rather dehydrated.
5. LIMITATIONS
● Because of the lack of equipment, we can only measure organisms that are
visible to the eye (macroinvertebrates)
● No soil chemical testing available so we cannot chemically analyze soil
composition; can only rely on visual appearance
● Human errors: Untrained, limited physical capabilities and amateur observations
- cannot distinguish species based on taxonomy
● Time constraints resulted in observations conducted in a 1 day interval
● Small study area: limit of 1 tree per site with 3 holes