Nitrogen Deposition Primary Effects on Forest Ecosystems

Relationships Among Stressors, Forests, and Aquatic Systems

*As Number and Severity of Stressors Increase,The Impacts to Forests and Associated Aquatic Systems Increase

STRESSORS-Air Pollutants-Altered Fire Regimes-Changes in Land Use--Urbanization-Exotic Species (Insects and Plants)

AQUATIC SYSTEMS-Chemistry-Sedimentation-Species Diversity-High and Low Flows

FOREST SYSTEMS-Growth-Reproduction-Mortality-Species Diversity-Tree Condition

Nitrogen Deposition Primary Effects on Forest Ecosystems

TreeGrowth

Stimulus

Nitrogen Saturation

Acidification Of SoilLoss of Nutrient Cations

Mobilization of Toxic Cations

Change ing Understory

SpeciesDiversity

Stream Degradation-Increased Cations-Decreased Water Quality-Decreased Aquatic Life

Changes inLichen

Diversity

Forest Degradation-Reduced Growth-Deteriorated Crowns-Increased Tree Mortality-Increased Sensitivity to Stressors

NitrogenFertilization

Relationships between Cations in Streams and Forest Health Indicators

UnderstorySpecies

Tree Growth, Mortality, &

Regeneration

CrownCondition

NutrientCations inStreams

Illustration of Multi-tier Concept

XNEE

XXDOC

XXMethane flux

XXSoil CO2 flux

XXLitterfall

XXXLive biomass

X*XXXDisturbance

XXXXLeaf area

XXXXLand cover

Tier 4Intensive Site

Tier 3Condition Sample

Tier 2Extensive Inventory

Tier 1Remote Sensing

Example

Variable

* Designed experiments

Tier 2 Surveys–USFS Forest Inventoryand Analysis (FIA)

Plots measured with a 5-year panel system to characterize forests of the Delaware River Basin.

Added 3 soil samples at 3 depths to each forested plot, + stream survey.

Focus on Appalachian Plateau (Northern Basin)

Neversink

Delaware Water Gap

French Creek

Fragmentation estimates from low-altitude CIR aerial photography

Stream survey preliminary results

N release typically happens with C/N below 23– all of Neversink is low C/N in streamwater. I need to have Kevin re-work this with a break at 25.

Headwaters are very low in Ca. Tree data could be correlated.

Mineral Soil Ca

0.00

0.050.10

0.150.20

0.25

0.300.35

0.40

Ridgetop Upper Mid Lower

ELEVATION

Ca

(cm

olc K

g-1)

Foliar Calcium

0

10

20

30

40

50

60

70

Ridgetop Upper Mid LowerSlope

mol

g-1

FW

Y. Birch

S. Maple

0

20

40

60

80

100

120

Ridgetop Upper Slope Mid-Slope Lower Slope

Pu

tre

scin

e (

nm

ol/g

)

Neversink Watershed

Calcium in Soil and Foliage of Yellow Birch and Sugar Maple, and levels of Putresine in Foliage

Neversink ISEMIntensification scheme

Phase 4 Plots

--probability estimate for entire watershed

Phase 5 Plots

--deliberately co-located with process studies

P4 Tree Data (25%)Neversink Watershed

0

20

40

60

80

100

120

140

STANDAGE CULL_PCT LENGTH_T DBH CRWNDEN CRWNDBK FOLTRAN TRDAM1 TRDAM2

Phase 4 PlotsNeversink Watershed--2001

0-10 cm Mineral Soils

0

1

2

3

4

5

6

7

8

9

Percent Total CarbonpH (water) Percent Total Nitrogen ECEC

pH

or

%

Cmolc/kg

Hypothetical Relationships among P4 + P5 Indicators

and Steam Condition

0

10

20

30

40

50

60

70

Die

ba

ck

Tra

ns

pa

ren

cy

So

il p

H

CE

C

Str

ea

m C

a

Biscuit Brook

Winnesok

Lawrence Falls

Murdoch Draw

Since Thresholds for Water Quality, for Human Consumption and Aquatic Life,

have been Established, they can be used toDetermine Thresholds for P4 and P5 Indicators.

By use of GIS and Analytical Models, the Indicator Values observed on P2 and P3 Plots can be

Analyzed using Ecologically-Meaningful Thresholds