Daniel G. Neary

Water quality of ephemeral forest streams after site preparation with the herbicide hexazinone

Abstract Four small watersheds (1 ha) in the upper Piedmont of north Georgia were treated with 1.68 kg ha −1 active ingredient of hexazinone [3-cyclohexyl-6-(dimethylamino)-1- methyl-1,3,5-triazine-2,4(1H,3H)-dione] pellets. Residues in stormflow peaked in the first strom (442 mg m −3 , declined rapidly thereafter, and disappeared within 7 months. Loss of hexazinone in stormflow averaged 0.53% of the applied herbicide. Suspended solids concentrations in runoff from the treated watersheds averaged 50.4 ± 7.9 g m −3 and were slightly more than those of the control (36.4 ± 5.4 g m −1 ). Total sediment yields were increased by a factors of 2.5 due to increased runoff associated with site preparation using herbicide and salvage logging. However, sediment loadings remained below those produced by mechanical techniques and well within levels common in relatively undistributed forests. Hexazinone treatment produced a large increased in NO 3 N concentrations (peak of 5328 mg m −3 ), but NO 3 N levels returned to normal within 2 years. Data indicate that hexazinone may have produced some stimulation of nitrifying bacteria. Cation concentrations increased 30–100% as a result of hexazinone application, but these increases were also transient. Overall, water quality changes were small and short-lived.

Flagstaff's wildfire fuels treatments: prescriptions for community involvement and a source of bioenergy

Abstract Flagstaff, Arizona, is a high elevation urban area in north-central Arizona surrounded by a dense ponderosa pine ( Pinus ponderosa ) forest. The annual wildland fire ignitions in and near to the urban area average over 200/year. Over the past 5 years, National Forest and city fire managers in the Wildland–Urban Interface (WUI) have developed a system of socially-welcomed fuel reduction treatments to reduce the wildfire threat to the community. These treatments have proven effective in reducing fire hazard, improving probability for successful initial attack on wildfires, maintaining and enhancing vegetative diversity, initiating improvement of overall forest health, and providing a local source of bioenergy. The long-term objective of the program is to facilitate socially acceptable stewardship of forested properties within the WUI. The Flagstaff WUI treatment prescription incorporates not only forestry and fire science, but also community and neighborhood input as vital components in successfully developing, implementing, and maintaining the treatments. Throughout the entire effort, project managers must maintain contact with and gather input from adjacent property owners and the community as a whole. Although current commercial markets are poor, there has been a great deal of success in utilizing bioenergy by designating free-use firewood areas. These events typically draw 200+ people who will remove 362 m 3 of wood in half a day. With over 1000 ha now treated, other benefits and lessons have been noted as well.

Water quality in New Zealand’s planted forests: a review

This paper reviewed the key physical, chemical and biological water quality attributes of surface waters in New Zealand’s planted forests. The purpose was to: a) assess the changes in water quality throughout the planted forestry cycle from afforestation through to harvesting; b) compare water quality from planted forests with other land uses in New Zealand; and c) identify knowledge gaps and opportunities for future research. Afforestation of pasture land significantly improved a wide range of water quality attributes such as stream temperature, nutrient and sediment concentrations and microbial contamination within 4-6 years of planting. Water quality in mid-rotation to mature forests, a large proportion of the forestry cycle, was highly variable but characterised by cool water temperatures, low concentrations of sediment and nutrients, with aquatic invertebrate communities indicative of high water quality. Impacts of timber harvesting on water quality attributes were greatest when clear-cut harvesting up to the stream edge. Harvest impacts were mediated by the retention of intact riparian buffers and to a lesser extent by retention of moderate quantities of logging slash across small stream channels. Temporal and spatial factors influenced the magnitude of response to harvesting activities and duration of the recovery period. Land-use comparisons generally showed improving water quality from pasture to planted forest to indigenous forest. Continued research to identify management systems that mitigate impacts on water quality, particularly during harvesting, remains a priority. Consistent approaches to water quality monitoring will improve the ability to report on water quality in planted forests. Future water quality research in New Zealand’s planted forests needs to encompass emerging contaminants of national and international concern such as pesticides and pharmaceuticals. As New Zealand moves toward increasing productivity from planted forests, use of potential interventions such as intensified herbicide and fertiliser use, will need to be within sustainable freshwater limits. A future challenge is to quantify the economic value of freshwater ecosystems services provided by New Zealand’s planted forests. This review showed that with continued prudent stewardship and ongoing improvements in management practices, particularly during harvesting, New Zealand’s planted forests can provide a sustainable source of well-maintained and high quality water resources.

Compromise programming in forest management.

ABSTRACT Multi-objective decision-making (MODM) is an appropriate approach for evaluating a forest management scenario involving multiple interests. Todays land managers must accommodate commercial as well as non-commercial objectives that may be expressed quantitatively and/or qualitatively, and respond to social, political, economic and cultural changes. The spatial and temporal characteristics of a forest ecosystem and the huge number of variables involved require the management of such a system in a spatiotemporal MODM framework. The particular MODM technique used in this paper is Compromise Programming. This technique is used to determine the most satisfactory management option, Compromise Programming uses a common management response indicator to solve a forest ecosystem management scenario in a fair and equitable manner.

Respiratory disease and particulate air pollution in Santiago Chile: contribution of erosion particles from fine sediments.

Air pollution in Santiago is a serious problem every winter, causing thousands of cases of breathing problems within the population. With more than 6 million people and almost two million vehicles, this large city receives rainfall only during winters. Depending on the frequency of storms, statistics show that every time it rains, air quality improves for a couple of days, followed by extreme levels of air pollution. Current regulations focus mostly on PM10 and PM2.5, due to its strong influence on respiratory diseases. Though more than 50% of the ambient PM10s in Santiago is represented by soil particles, most of the efforts have been focused on the remaining 50%, i.e. particulate material originating from fossil and wood fuel combustion, among others. This document emphasizes the need for the creation of erosion/sediment control regulations in Chile, to decrease respiratory diseases on Chilean polluted cities.

Snowpack-runoff relationships for mid-elevation snowpacks on the Workman Creek watersheds of Central Arizona

Snowpacks in the southwestern United States melt intermittently throughout the winter. At some mid-elevation locations, between 7,000 and 7,500 ft, snowpacks appear and disappear, depending on the distribution of storms during relatively dry winters. Some winter precipitation can occur as rain during warm storms and is not reflected in the snow course data. The USDA Natural Resources Conservation Service (NRCS) maintains a system of measuring stations to index snow conditions and predict snowmelt runoff. The three Workman Creek watersheds in the Sierra Ancha Experimental Forest north of Globe were instrumented in late 1938 to study the hydrology of southwestern mixed conifer forests and to determine changes in streamflow and sedimentation resulting from manipulating the forest cover. The watersheds were deactivated in 1983, but they were re-instrumented in June 2000 after the Coon Creek wildfire to measure fire effects on forest hydrology and sediment dynamics. The Rocky Mountain Research Station would like to use NRCS data from the Middle Fork of Workman Creek to reinforce its hydrologic data acquisition and interpretation efforts. Snow water equivalent data can be used to characterize past winter runoff volumes and peak mean daily runoff. Significant regressions were developed between the data sets with coefficients of determination values ranging from 0.40 to 0.77. The relationships defined by these regressions will allow researchers and managers to ascertain the impacts of fire on snowmelt-related hydrologic processes and to estimate winter flows for the years when the installations were closed. They also provide an insight into the snowpack runoff relationships for intermittent snowpacks that are common at intermediate elevations throughout Arizona.

RESIDUES OF LINDANE AND CHLORPYRIFOS IN FIREWOOD AND WOODSMOKE

Pine bark beetle insecticide treatment plots were established on the Ocala National Forest, in central Florida. Each plot consisted of five sand pine, pinus clausa (Chapm. Ex. Engelm) Vassey ex. Sarg., trees treated with either 0.5% lindane (benzene hexachloride) or 2% chlorpyrifos (O,O-diethyl O-(3,5,6-trichloro-2-pgridyl) phosphorothioate). After 4 months, mean residue levels ranged from 0.32 to 35.8 mg/kg for lindane and < 0.1 to 76.1 mg/kg for chlorpyrifos. Chlorpyrifos was more persistent in wood than lindane. In a separate laboratory study, lindane or chlorpyrifos were applied to powdered wood and then burned under controlled conditions to determine carryover in combustion products. With slow heating to 500°C (20”C/min.), 42.7% of the lindane and 28.3% of the chlorpyrifos were recovered in the smoke stream. With rapid combustion at 600°C all lindane and chlorpyrifos residues were thermally degraded. These findings were related to the risk of burning insecticide treated wood as firewood inside houses. Even under the worst case slow burning conditions, human exposure to airborne residues would be well under “safe-sided” threshold limit values and less than 0.2% of the acceptable daily intake established by the World Health Organization.

The 2002 Rodeo-Chediski Wildfire's impacts on southwestern ponderosa pine ecosystems, hydrology, and fuels

The Rodeo-Chediski Wildfire burned nearly 462,600 acres in north-central Arizona in the summer of 2002. The wildfire damaged or destroyed ecosystem resources and disrupted the hydrologic functioning within the impacted ponderosa pine (Pinus ponderosa) forests in a largely mosaic pattern. Impacts of the wildfire on ecosystem resources, factors important to hydrologic functioning, peak stormflow events and water quality constituents, and loadings of flammable fuels were evaluated on two watersheds in a ponderosa pine forest that was exposed to the burn - one experienced a high severity (stand-replacing) fire (Watershed A), and the other was exposed to only a low severity (stand-modifying) fire (Watershed B). Cumulative impacts of the wildfire on ecosystem resources, hydrologic functioning, and flammable fuels were more pronounced on Watershed A. Recovery of the Stermer Ridge watersheds from the Rodeo-Chediski Wildfire has been related to the respective fire severities that the two watersheds experienced. Watershed A converted from ponderosa pine to grasses, forbs, and a few shrubs. Recovery of the hydrologic functioning on this watershed has begun on a limited scale, but it is anticipated that the overall hydrologic functioning of Watershed A will not approach pre-fire conditions for many years. Flammable fuels represented by standing trees have been eliminated on Watershed A, but there has been an increase in stem sections, branches, twigs, and herbaceous fuels on the forest floor. While the possibility of a future crown fire has declined, the potential for surface fire remains. Much of Watershed B is slowly recovering from the impacts of the wildfire. Much of the hydrologic functioning of this watershed is also returning slowly to its pre-fire level. The post-fire loadings of flammable fuels were largely unchanged from their pre-fire estimates. Watershed B remains vulnerable to future wildfire events as a consequence.

Synthesis of Upper Verde River research and monitoring 1993-2008

This volume is a state-of-knowledge synthesis of monitoring and research conducted on the Upper Verde River (UVR) of Arizona. It contains information on the history, hydrology, soils, geomorphology, vegetation, and fish fauna of the area that can help land managers and other scientists in successfully conducting ecosystem management and future monitoring and research in this important Southwest river ecosystem. Chapter 1 provides an introduction to the UVRs location, vegetation, climate, soils, and watersheds. A historical and pictorial perspective of the UVR is presented in Chapter 2. The hydrology of the watershed and its current physical condition are covered in Chapters 3 and 4. Geomorphic relationships of the UVR channels are described in Chapter 5. The woody and herbaceous vegetation of the UVR are presented in Chapters 6 and 7. Water quality status and issues of the river are discussed in Chapter 8. The status of the fish fauna and other aquatic organisms are described in Chapter 9. Chapters 10 through 12 present summaries of information resources, research recommendations, a summary of this volume, and conclusions.Memo: Synthesis of Upper Verde River Research and Monitoring 1993-2009. (RMRS-GTR-291)

Fire effects on tree overstories in the oak savannas of the Southwestern Borderlands Region

Effects of cool-season and warm-season prescribed burning treatments and a wildfire on tree overstories in oak savannas on the Cascabel Watersheds of the Southwestern Borderlands Region are reported in this paper. Information on the initial survival, levels of crown damage, species compositions and densities, annual growth rates, and basal sprouting following these burning events is presented. Impact of the fires on spatial distributions of trees in the overstories is also described. These events were all of low fire severities. As a consequence, effects of the prescribed burning treatments and the wildfire on tree overstories of the watersheds were similar and, therefore, the data sets were pooled. Effects of these fires on the tree overstories were mostly minor and often insignificant in terms of management implications.