Chin hills pine savanna

ချင်းတောင်တန်း ထင်းရှူးနှင့် မြက်ခင်းတော

Extinction Risk

NE
DD
National IUCN statusLC
NT
VU
EN
CR
CO

Climate and ecology

Realm

Terrestrial

Biome

Savannas And Grasslands

Functional Group

Pyric tussock savannas

Description

Pine savannas are grassy ecosystems with open to closed evergreen needleleaf tree canopies.

Distribution

Chin Hills pine savanna occurs along the Chin Hills in western Myanmar, where it is patchily distributed along the range between around 800 to 1,500 m (Davis, 1960) and perhaps up to 2,000 m (Farjon, 2013).

Characteristic

Native biota

Details

This ecosystem is dominated by near-monotypic stands of Khasia Pine, Pinus kesiya (Pinaceae), local name Tinyu. The ecosystem is generally less biodiverse than surrounding hardwood forests.

Abiotic environment

Mean temperature

No data

Soil

Low-nutrient and well-draining soils with sandy or loamy texture

Precipitation

>1,000 mm per annum

Elevation

800 - 2,000 m

Details

The Chin Hills pine savanna is found at altitudes of 800 – 1,500 m, possibly up to 2,000 m, where temperatures are cooler than on adjacent lowlands where other savanna ecosystems occur. They occur on low-nutrient and well-draining soils with sandy or loamy texture (Davis, 1960). Rainfall is typically greater than 1,000 mm per annum and highly seasonal due to the monsoons.

Key processes and interactions

Pine savanna ecosystems are thought to be maintained by fire (Ratnam et al., 2016; Van Zonneveld et al., 2009). The ground layer is dominated by fire-adapted grasses, which propagate fire when they cure in the dry season. The characteristic pines survive low and relatively high intensity fires due to their thick bark, which insulates sensitive cambial and vascular tissues form fire temperatures (Ratnam et al., 2016). Most broad-leaf tree species lack such traits, and have lower survival rates post-fire. Where fires are rare or supressed, Asian pine savanna ecosystems tend to be invaded by hardwood forest species from surrounding ecosystems.

Major threat

Major threat

Threats to this ecosystem include deforestation for agriculture, felling for firewood, and fire suppression (Farjon, 2013, Ratnam et al., 2016, Van Zonneveld et al., 2009). Climate envelope models suggest that climate change is not expected to affect P. kesiya significantly, primarily because the species has been shown to occur in a very wide range of climatic conditions (Van Zonneveld et al., 2009)

Instruction: The visualization shows threats that are present within each ecosystem. According to IUCN, direct threats are the proximate human activities or processes that have impacted, are impacting, or may impact the the status of the taxon being assessed. Click of the highlighted icons to see details each threat category.

Ecosystem Assessment

Assessment Summary

Remote sensing models suggest this ecosystem is relatively broadly distributed across the Chin Hills. No historical information on the distribution of this ecosystem was found, and an assessment of primary forest within the extant distribution suggests degradation has not occurred to an extent sufficient to meet category thresholds for Criterion D. Climate change is not expected to significantly affect the primary species of Pinus, but we do recommend further work to assess climate change impacts for this ecosystem. Least Concern.

Instruction: Click on the chart to view the detailed assessment result for each RLE risk criteria. Risk is defined as the probability of an adverse outcome over a specified time-frame. Here, the adverse outcome is the endpoint of ecosystem decline, which the RLE terms ecosystem collapse.

Ecosystem collapse definition

This system is considered collapsed when its distribution declines to 0 km2 or when the proportion of the ecosystem considered primary forest declines to 0.

Date Assessed

2019-03-08

Year published

2019

Assessed by

Hedley Grantham,Nicholas Murray

Reviewed by

David Keith

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