Treesearch

Ground-based ecosystem monitoring presents some practical challenges to natural resource managers and ecologists tasked with assessing vegetation dynamics across large areas through time. RangeView (http://rangeview.arizona.edu) provides online access to spatially and temporally explicit biweekly vegetation indices derived from satellite data. It also permits side-by-side comparisons of different periods and relative greenness products (e.g., difference from average). Qualitative visualization of vegetation dynamics could be enhanced with quantitative assessment of phenology for specific...

A variety of efforts are taking place to detect, inventory, and monitor the wild felids (pumas, bobcats, jaguars, and ocelots) of the Madrean Archipelago. Researchers are using a suite of noninvasive methods, including infrared-triggered photography, DNA analysis of scat and hair (collected from “hair snares”), and old-fashioned tracking and sign searches. These efforts are being conducted by a variety of academic, government, and non-governmental organizations in the United States and Mexico. We briefly outline the various projects including their results to date, discuss threats to...

We studied patterns of biodiversity across the entire urban, suburban, agricultural, and surrounding Sonoran Desert landscape of central Arizona-Phoenix. A probability-based extensive integrated field inventory was used to survey perennial plants, pollen, birds, and sample soil chemistry, supplemented by monthly or quarterly monitoring of arthropod and bird communities at some sites. For taxa and ecosystem properties directly manipulated by people (e.g., perennial plant diversity, pollen) dominantly geomorphic controls in undeveloped desert were replaced by factors such as land use,...

The objective of this study was to develop a rule based cover type classification system for the forest and woodland vegetation in the Sky Islands of southeastern Arizona. In order to develop such a system we qualitatively and quantitatively compared a hierarchical (Ward’s) and a non-hierarchical (k-means) clustering method. Ecologically, unique groups represented by only a few plots were appropriately distinguished using k-means, while Ward’s combined these unique plots into the large mixed conifer groups. Similarly, plots dominated by more than one species were more appropriately grouped...

I was asked to speak to you concerning 20 years of nursery history from a Forest Service perspective. I hope you will allow me a little leeway here, because while I will focus on events of the past 2 decades, I find it necessary to begin by going a little further back in time.Individual papers from this publication

A pilot project to identify climate monitoring needs within Saguaro National Park began in fall 2003. Nine weather stations were deployed across the complex topography of the park to provide insight into the spatial and temporal patterns of climate within the park management unit. This project will provide a valuable baseline for park management and may highlight unique spatial and temporal patterns that deserve further investigation. Project findings will help dictate long-term climate monitoring strategies for the park and other park units.

About 1,500 collections from within 100 kilometers of the Arizona border in Sonora yielded noteworthy records for 164 plants including 44 new species (12 non-native) for Sonora and 12 (six non-native) for Mexico, conservation species, and regional endemics. Many common widespread species were poorly collected. Southern range extensions (120 species) were more numerous than northern extensions (20), although nine potentially occur in Arizona. Non-native species dispersed along highways and escaped from cultivation. The Turkish poppy (Glaucium corniculatum), established near Agua Prieta, may...

The floras of the “Sky Island” Huachuca Mountains, Arizona (994 taxa; 316 km²; 1,524-2,885 m elevation, 1,361 m elevational range; 31°30’N) and the “mainland” Sierra Madre Occidental near Yécora, Sonora (1,284 taxa; ca. 2,080 km²; 820-2,140 m, 1,320 m elevational range; 28°24’N) were compared. Only 6.5% and 5.1% of the floras were non-native. Compositae, Gramineae, and Leguminosae contained 39.3% and 40.2% of the taxa. The Apachian floristic element (38.8%) in the Huachuca flora best reflected the 39.9% native taxa shared with Yécora. The plant diversity in the Yécora area is much greater...

We surveyed historic and nearby collecting localities for Aspidoscelis (= Cnemidophorus) arizonae in Cochise and Graham Counties, Arizona, during spring and summer, 2000-2003. Aspidoscelis arizonae was present at or nearby all but one of the historic sites (seven of eight) that we surveyed located near Willcox (within 15 km), but not the type locality 65 km to the west at Fairbank, Cochise County, nor the Whitlock Valley 65 km to the northeast in Graham County. The Desert Grassland Whiptail, A. uniparens, was present at most sites unoccupied by A. arizonae, including the type locality;...

Mitochondrial sequence data from three species of flightless cactus beetles, Moneilema gigas, M. armatum, and M. appressum, were analyzed. The coalescent models implemented in the program FLUCTUATE were used to test the hypothesis that these species experienced range changes following the end of the last glacial period. The two desert species M. gigas and M. armatum both showed significant evidence of population growth, particularly in northern populations; however, the montane species M. appressum did not show evidence of range fragmentation and population decline as predicted from...