Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico

Area of Science:

• Forest Ecology
• Biogeochemistry
• Environmental Science

Background:

• Forest canopies play a crucial role in modulating precipitation reaching the forest floor.
• Understanding the chemical composition of throughfall and stemflow is vital for assessing nutrient cycling and ecosystem health.
• Variations in canopy structure and species composition can influence these processes.

Purpose of the Study:

• To quantify interception loss, throughfall, and stemflow chemistry under different forest canopies (pine, oak, pine-oak).
• To compare nutrient deposition and leaching rates among these forest types.
• To analyze the influence of canopy type on the chemical characteristics of precipitation reaching the forest floor.

Main Methods:

• Field measurements of gross precipitation, throughfall, and stemflow were conducted over a period with 974 mm of rainfall.
• Solution chemistry (pH, electrical conductivity) and nutrient concentrations (macro- and micro-nutrients) were analyzed.
• Statistical analyses, including linear regression, were used to assess relationships and differences.

Main Results:

• Interception loss varied by canopy type (13.6% oak, 19.2% pine, 23% pine-oak).
• Throughfall pH was more acidic than gross precipitation across all canopies.
• The pine-oak canopy exhibited higher throughfall and stemflow electrical conductivity and significantly greater net nutrient leaching for several elements (K, Mg, Na, Fe, Mn, Zn).

Conclusions:

• Forest canopy type significantly influences water chemistry and nutrient dynamics in precipitation reaching the forest floor.
• Mixed pine-oak canopies can enhance nutrient leaching and deposition compared to pure stands.
• These findings are critical for understanding nutrient cycling in forest ecosystems and potential impacts of forest composition changes.