Climate and Soils for Tropical Horticultural Crops Lecture Flashcards

A set of vocabulary flashcards covering the key climatic and soil-related terminology used in tropical horticultural crop production as presented in the lecture notes.

Lapse rate

The rate at which temperature decreases by $0.6^{\circ}\text{C}$ for every $91.5\,\text{m}$ rise in elevation from sea level.

Light saturation point

The point in photosynthesis where the entire photosynthetic machinery of the plant operates at maximum capacity and the rate no longer increases with light intensity.

Heliophytes

Sun-loving plants that reach light saturation at approximately $53,763\,\text{lux}$ (or $5,000\,\text{foot-candles}$) and require full sun for optimal growth.

Sciophytes

Shade-loving plants that reach light saturation at approximately $5,376\,\text{lux}$ (or $500\,\text{foot-candles}$).

Photoperiodism

A phenomenon where plants respond to the length of the photoperiod, which is the duration of daylength from dawn to dusk.

Type 1 Climate

A classification in the Philippines characterized by two pronounced seasons: dry from November to April and wet during the rest of the year, with maximum rain from June to September.

Type 2 Climate

A classification with no dry season and a very pronounced maximum rain period from November to January (expressed as December to February in some models), where there is not a single dry month.

Soil texture

The relative proportion of three particle types: sand ($\ge 0.5\,\text{mm}$), silt ($0.05-0.002\,\text{mm}$), and clay ($\le 0.002\,\text{mm}$).

Organic matter (OM)

A component derived from plant and animal remains that improves soil structure, water-holding capacity, and serves as a source of nitrogen ($5\%$ of its content).

Soil structure

The arrangement of soil particles bound together by organic matter into larger, water-stable aggregates called crumbs or peds.