Pak. J. Bot., 39(5): 1717-1724, 2007. | Back to Contents | ||||
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Updated: 09-07-09 | ||||
IMPACT OF MICROHABITAT ON SURVIVAL OF SERIPHIDIUM QUETTENSE SEEDLINGSSHAMIM GUL*, SARFRAZ AHMAD**, ABDUL KABIR KHAN ACHAKZAI* AND MOHAMMAD ISLAM**
Abstract:
Two years study
was conducted to examine the influence of microhabitats i.e., plant
canopies and interspaces on the seedling emergence and survival of
Seriphidium quettense in relation to soil temperature and soil
moisture in natural habitat. The growth rate of first year seedlings are
also examined. Relative abundance of microhabitats was determined by
using square quadrates. Soil temperature and soil moisture of two
microhabitats were recorded at 0-5, 5-10 and 10-15 cm depth. Results
showed that soil moisture in spring was found critical for seed
germination while in summer it had greater impact on the survival of
first year seedlings. Precipitations in March and April promoted seed
germination while monsoon rains influenced seedling survival. Soil
moisture and soil temperature in different microhabitats were
significantly different in different months, reflected significant
influence upon seedling emergence and their survival. Seedling emergence
and survival was higher under plant canopies than in open interspaces.
Highest mortality rate of first year seedlings were observed in June and
August under high soil temperature and low soil moisture contents. High
soil moisture in July due to occurrence of precipitation decreased the
mortality rate of first year seedlings. After winter, no mortality
occurred. Survived seedlings of the first year had high root to shoot
ratio. Results further depicted that conspecific plant canopies are
favorable microsites for seedling survival. Furthermore, high root to
shoot ratio may enable them to survive in arid habitat.
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