2000 Progress Report: Foliar Chemistry as an Indicator of Forest Ecosystem Status, Primary Production and Stream Water Chemistry

EPA Grant Number: R825865
Title: Foliar Chemistry as an Indicator of Forest Ecosystem Status, Primary Production and Stream Water Chemistry
Investigators: Aber, John , Bailey, Scott , Driscoll, Charles T. , Hallett, Richard , Martin, Mary , Ollinger, Scott , Smith, Marie-Louise
Current Investigators: Aber, John , Bailey, Scott , Hallett, Richard , Martin, Mary , Ollinger, Scott , Smith, Marie-Louise
Institution: University of New Hampshire - Main Campus
EPA Project Officer: Hahn, Intaek
Project Period: June 1, 1998 through May 31, 2001
Project Period Covered by this Report: June 1, 1999 through May 31, 2000
Project Amount: $850,000
RFA: Ecosystem Indicators (1997) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Ecosystems

Objective:

The study area is the White Mountain National Forest, a 300,000 ha area in northern New Hampshire (see Figure 1). Monitoring the biogeochemical status of forest and stream ecosystems is a key component of assessing environmental quality in the northeastern United States. Any monitoring system requiring spatially-continuous capabilities will need to use some form of remote sensing. Forest canopies are the only portion of the system accessible to optical reflectance remote sensing instruments, and so offer the most likely target surface for monitoring forest health in this spatial mode.

Forest productivity, soil chemistry, and foliar chemistry at the whole stand level are tightly linked to the biogeochemical status of the forest ecosystem and so to each other. If true, then stream water chemistry, averaged over some time period, can be predicted from foliar chemistry.

Progress Summary:

Strong relationships between whole stand level foliar canopy N, NPP and forest floor C:N ratios exist (Figure 2). Further analysis will determine if foliar cation concentrations are correlated with forest productivity.

Stream water sampling was initiated (November 1999) from 50 streams in the WMNF covering a range in estimated mineralogical richness. The sampling schedule involved quarterly sampling through August 2000. A nested approach was used to allow us to test the optimum scale at which stream water chemistry may be predicted.

We have established that foliar N and Ca can be mapped across the WMNF (300,000 ha) using remote sensing technology (Figures 3a and 3b). Foliar N is a good predictor of forest productivity. The relationship between foliar Ca and productivity needs to be examined.

Figure 2. Canopy-soil-stand interactions at the Bartlett Experimental Forest showing a) foliar nitrogen concentration in relation to forest floor C:N ratio, b) foliar nitrogen concentration in relation to aboveground net primary production, c) forest floor C:N ratio in relation to aboveground net primary production, and d) forest floor C:N ration in relation to annual net nitrification in soils.

A GIS model has been developed for the WMNF that predicts the element content of the glacial till (Figure 4). The predictions for till Ca have been compared to plot level foliar Ca data and a significant relationship exists (Figure 5).

Figure 4. Predicted till Ca for the WMNF.

The following progress was made during the past year:

  • Stream water sampling was completed and all samples were analyzed, wide ranges in key elements were observed (Table 1).
  • Low altitude (3 m resolution) AVIRIS imagery was collected for 30 of the 50 watersheds in this study. This gives us the ability to look at these areas in much greater detail. Efforts are under way to use this imagery to generate detailed species maps of the study areas.
  • Foliage was collected from 200 plots located within the area covered by the low altitude AVIRIS imagery. These samples are being analyzed for cellulose, lignin, N, Ca, Mg, Mn, and Al. Data from these samples will be used as calibration and validation for AVIRIS predicted foliar chemistry maps.
Nov-99
pH
Nitrate (ueq/L)
Sulfate (ueq/L)
DOC:DON
Ca (ueq/L)
Mg (ueq/L)
Mean
6.18
2.49
27.30
14.67
72.17
26.18
Minimum
4.92
0.00
18.21
3.69
41.98
11.00
Maximum
6.85
12.84
47.70
37.75
125.37
56.44
Feb-00
pH
Nitrate (ueq/L)
Sulfate (ueq/L)
DOC:DON
Ca (ueq/L)
Mg (ueq/L)
Mean
6.42
3.38
27.53
18.60
98.35
35.46
Minimum
5.64
0.84
16.85
4.73
50.55
10.23
Maximum
7.16
13.05
45.58
43.83
211.63
83.15
May-00
pH
Nitrate (ueq/L)
Sulfate (ueq/L)
DOC:DON
Ca (ueq/L)
Mg (ueq/L)
Mean
5.77
2.40
23.34
27.94
59.39
19.32
Minimum
4.71
0.10
15.39
13.34
36.40
8.20
Maximum
6.61
9.36
35.43
45.33
102.46
35.64
Aug-00
pH
Nitrate (ueq/L)
Sulfate (ueq/L)
DOC:DON
Ca (ueq/L)
Mg (ueq/L)
Mean
6.52
1.82
26.11
18.31
83.27
28.32
Minimum
4.94
0.02
15.56
5.25
42.11
9.69
Maximum
7.18
8.18
46.49
42.00
185.60
78.89

Table 1. Means and ranges for key elements and compounds measured in quarterly stream water samples.

Future Activities:

During the next year we will process and analyze new AVIRIS imagery from low altitude platform for selected watersheds (AVIRIS low altitude data; 3-4 m resolution). We also will use soil and foliar element coverages to develop relationships with measured stream water chemistry and forest productivity.


Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other project views: All 16 publications 3 publications in selected types All 3 journal articles
Type Citation Project Document Sources
Journal Article Ollinger SV, Smith ML, Martin ME, Hallett RA, Goodale CL, Aber JD. Regional variation in foliar chemistry and N cycling among forests of diverse history and composition. Ecology 2002;83(2):339-355. R825865 (2000)
R825865 (Final)
  • Abstract: ESA Abstract
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  • Supplemental Keywords:

    forest ecosystem, primary production, nitrogen, indicator, cation supply, New Hampshire, NH, remote sensing, monitoring, water quality., RFA, Scientific Discipline, Water, Ecosystem Protection/Environmental Exposure & Risk, Water & Watershed, Ecology, Hydrology, Ecosystem/Assessment/Indicators, Ecosystem Protection, Environmental Chemistry, exploratory research environmental biology, Chemical Mixtures - Environmental Exposure & Risk, Chemistry, Ecological Effects - Environmental Exposure & Risk, Forestry, Ecological Effects - Human Health, Agronomy, Watersheds, Ecological Indicators, remote sensing, soil water chemistry, biogeochemical indicators, climate change impact, forest ecosystems, hydrological, stream ecosystems, stream water chemistry, aquatic ecosystems, water quality, forested watershed, foliar chemistry, climate variability

    Progress and Final Reports:

    Original Abstract
  • 1998
  • 1999 Progress Report
  • Final Report