Search Filter

Keywords:

 

Asian Journal of Agriculture and Development (AJAD) - Call for papers!

Morpho-physiological Characteristics and Soil Moisture Relationships in Some Plant Species of Upland Ecosystems

(Malaysia), Master of Science in Botany (University of the Philippines Los Baños)

Thesis Abstract:

The soil moisture contents of five upland ecosystems, found at the University of the Philippines Los Baños (UPLB) Upland Hydroecology Program Main Site at Puting Lupa, Calamba, Laguna, were monitored daily over a two-month period, covering the wet and dry seasons. Daily records of solar radiation, sunshine duration, rainfall, and air temperature were also monitored. Soil temperature at 5 cm below the soil surface were obtained daily in the same ecosystem for four months, mostly during the dry season.

Significant differences in soil moisture contents and soil temperatures were found to occur among the ecosystems. Soil moisture was negatively correlated with solar radiation and positively correlated with rainfall. Except for the grassland ecosystem, all the other ecosystems showed significant differences in oil moisture contents among different slopes (30º, 50º, and 70º). However, the differences were not consistent from one ecosystem to another.

There was highly significant negative correlation between soil moisture content and soil temperature in the grassland, new kaingin (slash-and-burn), and old kaingin ecosystems, but not in the plantation and secondary forest ecosystems.

The leaf stomatal densities and distribution, leaf relative water contents, leaf moisture contents, leaf stomatal diffusion, resistances, and leaf temperatures were studied in seven plant species as they occured in the five ecosystems. Significant positive correlation between soil moisture content and leaf relative water content was found only in Gliricidia sepium. Two species, Carica papaya and Ficus septica, showed significant positive correlation between soil moisture content and  leaf moisture content. In Musa paradisiaca, soil moisture content was negatively correlated with leaf stomatal diffusion resistance. Psidium guajava showed highly significant negative correlation between leaf temperature and stomatal diffusion resistance. Three species, namely; C. papaya, I. cylindrica, and G. sepium showed significant positive correlation between leaf relative water content and leaf moisture content. The other species, Saccharum spontaneum, did not show any correlation among the various parameters.

The ecological significance of the various relationships and characteristics of the environmental and plant factors, as exhibited in their individual ecosystems, were discussed and possible explanations were offered.