Kansas NASA EPSCoR Rural Resources Cluster
Forest Cover at Ft. Leavenworth, Kansas, 1996-2001

**Table of Contents**
Introduction	More images
Color-infrared photos	Research findings
Publications	Coauthors

Introduction

Earth science research at Emporia State University under the Kansas NASA EPSCoR program is directed toward understanding response of forest cover and wetland to climatic events and human impact during the past three decades. This project is part of a larger effort to model changes in rural resources of Kansas, conducted in cooperation with Kansas State University and the University of Kansas.

The forest project includes Landsat and IKONOS satellite imagery, climatic records, tree-ring cores from oaks, and ground observations in upland (oak) and bottomland (cottonwood) study forests at Fort Leavenworth, Kansas. In addition, we are developing techniques in kite aerial photography (KAP) to acquire low-height, large-scale, high-resolution imagery of the forest canopy. The satellite image below depicts the Fort Leavenworth vicinity in 1987, a year that was especially good for tree growth.

Landsat TM false-color composite based on bands 3 (red), 4 (near-IR) & 5 (mid-IR) color coded respectively as blue, green and red. In this composite, active vegetation appears in green, yellow-green, and olive-brown colors. The upland study forest consists of deciduous, hardwood trees growing on a bedrock ridge. The bottomland study forest is located within the large meander loop of the Missouri River. This forest is dominated by fast-growing cottonwood and willow.

More Imagery of Ft. Leavenworth Vicinity

	Special false-color composite. Landsat image consisting of green, near-infrared, and mid-infrared light portrayed in a false-color manner. Active vegetation appears green, bare soil and fallow fields are red-pink, and urban structures are purple. All water bodies, including the Missouri River, are black in this composite. KCI is Kansas City International Airport. Image date 28 Sept. 1994; TM bands 2, 4, 7; image processing by J.S. Aber ©. Click on small image to see a full-sized (223 kb) version.
	Space-shuttle photograph of the Kansas City-Leavenworth region. Color-visible picture from autumn. Dark blue depicts forest cover and some water bodies; light gray indicates fallow fields and urban areas. The study site at Ft. Leavenworth is marked by the green dot at scene center. Manned-space photograph 61A-481-07, 11/85, acquired from the NASA Johnson Space Center--Imagery Services.
	Kite aerial photograph northward along bedrock ridge on west side of Ft. Leavenworth. The mixed deciduous forest consists of various oaks, walnut, hickory, and other hardwood trees. This mature forest has grown up during the past 150 years. Some cloud shadows can be seen in this late spring view, and the Missouri River is visible in the upper left corner. Photo date 5/98; © J.S. Aber. Click on small image to see a full-sized (102 kb) version.
	Kite aerial photograph of study forest. This early May view depicts trees in partial-leaf mode; branches and tree trunks are visible. Very little understorey vegetation is present. Photo date 5/99; © J.S. Aber. Click on small image to see a full-sized (189 kb)version.

Color-Infrared Photographs

Low-height color-infrared photographs, taken from a kite, provide detailed images of vegetation cover. Such photography captures the green, red, and near-infrared energy, which is displayed in a false-color format. Active vegetation reflects near-infrared radiation strongly, whereas red light is strongly absorbed. The result is that active vegetation appears bright red and pink in color-infrared photographs. Other materials--bare soil, pavement, water--are depicted in green and blue colors. On this basis color-infrared pictures are particularly useful for analysis of vegetation cover.

April 2000
Late April views south over the upland study forest on the west side of Ft. Leavenworth. Cool-season grass (brome, fescue) is bright pink-red (left) in the cleared strip along Sheridan Drive. Color-infrared (left), color-visible (right); photo date 21 April 2000, © J.S. Aber.
Closeup views of upland study forest showing pink crowns in some trees (left) at the beginning of the growth season. Although trees appear green (right), the color is mainly from flowers; the trees are just beginning to leaf out at this time of year. Color-infrared (left), color-visible (right); photo date 21 April 2000,© J.S. Aber.

Bottomland study forest on the Missouri floodplain. The adjacent prairie was burned intentionally just a few days prior to this shot. This view reveals that fire invaded the forest understory. The cottonwood trees are covered with green flowers at this time of year. Compare with May images below. Color-visible; photo date 21 April 2000.

May 2000
Late May views south over the upland study forest on the west side of Ft. Leavenworth. The bright red and pink colors indicate fully developed forest canopy. Color-infrared (left), color-visible (right); photo date 22 May 2000, © J.S. Aber.
Vertical views over the upland study forest on the west side of Ft. Leavenworth. Note the rough surface of the forest canopy with many shadowed pockets around the tree crowns. Color-infrared (left), color-visible (right); photo date 22 May 2000, © J.S. Aber.
Bottomland forest. The dull purplish-red color (left) indicates the forest canopy and understory are not yet fully developed at this time of year. Parallel lines of trees reflect meander scrolls on the floodplain. A few dead trees at the forest periphery (right) may have been killed by the prairie burn of the previous month. Color-infrared (left), color-visible (right); photo date 22 May 2000, ©J.S. Aber.

June 2001
Closeup view of bottomland forest margin with canopy in full development. Notice dead trees along the edge of the forest; these trees were killed by the prairie fire the previous year. Compare with April 2000 image above. Photo date 12 June 2001, © J.S. Aber.

**June 2001**
	Closeup view of bottomland forest margin with canopy in full development. Notice dead trees along the edge of the forest; these trees were killed by the prairie fire the previous year. Compare with April 2000 image above. Photo date 12 June 2001, © J.S. Aber.

Left: low-oblique view of upland forest next to the Hunt Lodge. Right: near-vertical view of upland forest in same locality. Full-canopy development is evident in these late-spring images. Photo date 12 June 2001, © J.S. Aber.

Research Findings

Our findings are based on analysis of Landsat TM imagery for mid-summer (July) scenes for the period 1987-97 in combination with climatic data and tree-ring records. Main points are summarized briefly below and elaborated in the publications listed at the end of this page. A review of research methods and findings for the overall study is given in Aber et al. (2002).

Study forests -- The study forests can be separated in Landsat TM imagery from all other types of vegetation and surface cover by a combination of unsupervised classification, grouping, and masking techniques. Furthermore, upland and bottomland forest can be distinguished by use of the Landsat TM band 5/4 ratio.
Tree-ring record -- Tree-ring growth responds to drought and other climatic events in the same year as the drought. Storage of carbon in tree wood responds immediately to climatic variations.
Vegetation index -- The normalized difference vegetation index (NDVI) responds to drought and other climatic events with a 1-2 year lag period. This has important implications for utilizing NDVI values to assess forest conditions. NDVI is out of phase with climatic variations.

Canopy roughness -- Mature hardwood forest has rough canopy, at the scale of meters, which includes many "pockets" that are shadowed. Such shadows may depress satellite-derived NDVI values in comparison to forest with smooth canopy.

Left: ground view in the interior of the upland study forest. Notice the rather sparse understory vegetation and heavy shadowing of the forest floor.
Right: View looking upward beneath a white oak in the upland study forest. White oaks are among the tallest trees and often stand several meters above other trees.

Digital-camera images; photo date 12 May 2001, © J.S. Aber.

Publications, Presentations, and Theses

Aber, J.S., Aber, S.W. and Leffler, B. 2001. Challenge of infrared kite aerial photography. Kansas Academy Science, Transactions 104(1/2), p. 18-27--see online article.
Aber, J.S., Harrington, J. and Nowak, M.C. 1999. Kite aerial photography for forest assessment at Fort Leavenworth, Kansas. Proceedings--From image to information, p. 484-490 (on CD-ROM). American Society of Photogrammetry and Remote Sensing, Annual Conference, Portland, Oregon, May 17-21, 1999--see abstract.
Aber, J.S., Nang, K.N. Wilkins, N., Hengchun Ye, Harrington, J. and Nowak, M.C. 1998. Remote Sensing of Forest Growth and Response to Climatic Variations in Northeastern Kansas, U.S.A. 27th International Symposium on Remote Sensing of Environment, Proceedings, p. 709-714. Tromsø, Norway, June 8-12, 1998--see abstract.
Aber, J.S., Sobieski, R., Distler, D.A. and Nowak, M.C. 1999. Kite aerial photography for environmental site investigations. Kansas Academy Science, Transacations 102, p. 57-67--see abstract.
Aber, J.S., Wallace, J. and Nowak, M.C. 2002. Response of forest to climatic events and human management at Fort Leavenworth, Kansas. Kansas Geological Survey, Current Research in Earth Sciences, Bulletin 248, part 1--see online article.
Aber, J.S., Ye, H., Zeeberg, J.J., Nang, K.N. and Nellis, M.D. 1997. Remote sensing of forest conditions in northeastern Kansas--Research methods and limitations. Kansas Academy Science, Abstracts 16, p. 8--see abstract.
Nang, K.N. 1998. Remote sensing and tree-ring study of forest condition in northeastern Kansas. Unpub. Master's thesis, Emporia State University, Emporia, Kansas, 67 p.
Pavri, F., Aber, J.S., Tilton, J. and Wallace, J. 2001. Methods for assessing forest cover trends in northeastern Kansas: Multi-date and band Landsat TM image composites. Abstract for presentation at Annual Meeting of the Great Plains/Rocky Mountain Division of the Association of American Geographers, Omaha, Nebraska, Sept. 27-29, 2001. See abstract.
Pavri, F., Aber, J.S., Tilton, J. and Wallace, J. 2001. Detecting and explaining forest cover change in northeastern Kansas through remote sensing and historical analyses. Abstract for Annual Applied Geography Conference, Fort Worth, Texas, Nov. 14-17, 2001.
Wallace, J.A. 2000. Temporal studies of deciduous forests in northeastern Kansas using Landsat Thematic Mapper images. Unpub. Master's thesis, Emporia State University, Emporia, Kansas, 142 p.
Wilkins, N.H. 1997. Analysis of forest change at Fort Leavenworth, Kansas, using Landsat Thematic Mapper data. Unpub. Master's thesis, Emporia State University, Emporia, Kansas, 83 p.

Investigation Coauthors

James S. Aber,
Emporia State University

Matt Nowak,
Fort Leavenworth

Firooza Pavri,
Emporia State University

More on kite aerial photography at Ft. Leavenworth--see KAP.
Lewis and Clark space-age atlas--see L&C.

NASA EPSCoR at ESU.
Last update 26 Feb. 2002.

	Late April views south over the upland study forest on the west side of Ft. Leavenworth. Cool-season grass (brome, fescue) is bright pink-red (left) in the cleared strip along Sheridan Drive. Color-infrared (left), color-visible (right); photo date 21 April 2000, © J.S. Aber.
	Closeup views of upland study forest showing pink crowns in some trees (left) at the beginning of the growth season. Although trees appear green (right), the color is mainly from flowers; the trees are just beginning to leaf out at this time of year. Color-infrared (left), color-visible (right); photo date 21 April 2000,© J.S. Aber.

	Late May views south over the upland study forest on the west side of Ft. Leavenworth. The bright red and pink colors indicate fully developed forest canopy. Color-infrared (left), color-visible (right); photo date 22 May 2000, © J.S. Aber.
	Vertical views over the upland study forest on the west side of Ft. Leavenworth. Note the rough surface of the forest canopy with many shadowed pockets around the tree crowns. Color-infrared (left), color-visible (right); photo date 22 May 2000, © J.S. Aber.
	Bottomland forest. The dull purplish-red color (left) indicates the forest canopy and understory are not yet fully developed at this time of year. Parallel lines of trees reflect meander scrolls on the floodplain. A few dead trees at the forest periphery (right) may have been killed by the prairie burn of the previous month. Color-infrared (left), color-visible (right); photo date 22 May 2000, ©J.S. Aber.