Access Restriction

Author McBroom, Matthew W. ♦ Beasley, R. Scott ♦ Chang, Mingteh ♦ Ice, George G.
Source World Health Organization (WHO)-Global Index Medicus
Content type Text
Publisher American Society of Agronomy
File Format HTM / HTML
Language English
Difficulty Level Medium
Subject Domain (in DDC) Social sciences ♦ Social problems & services; associations ♦ Social welfare problems & services ♦ Natural sciences & mathematics ♦ Chemistry & allied sciences ♦ Life sciences; biology ♦ Physiology & related subjects ♦ Biochemistry ♦ Technology ♦ Medicine & health ♦ Human physiology ♦ Personal health & safety ♦ Pharmacology and therapeutics ♦ Diseases ♦ Agriculture & related technologies ♦ Techniques, equipment & materials
Subject Domain (in MeSH) Inorganic Chemicals ♦ Chemical Actions and Uses ♦ Chemicals and Drugs ♦ Physical Phenomena ♦ Biological Phenomena ♦ Biological Sciences ♦ Technology, Industry, and Agriculture ♦ Technology and Food and Beverages ♦ Environment and Public Health ♦ Health Care ♦ Geographic Locations ♦ Geographic Locations
Subject Keyword Discipline Environmental Health ♦ Fertilizers ♦ Forestry ♦ Methods ♦ Water Pollutants, Chemical ♦ Analysis ♦ Ammonia ♦ Environmental Monitoring ♦ Nitrates ♦ Nitrogen ♦ Phosphates ♦ Phosphorus ♦ Rain ♦ Rivers ♦ Chemistry ♦ Texas ♦ Water Movements ♦ Water Pollution ♦ Water Supply ♦ Journal Article ♦ Research Support, Non-u.s. Gov't
Abstract Nine small (2.5 ha) and four large (70-135 ha) watersheds were instrumented in 1999 to evaluate the effects of silvicultural practices with application of best management practices (BMPs) on stream water quality in East Texas, USA. Two management regimes were implemented in 2002: (i) conventional, with clearcutting, herbicide site preparation, and BMPs and (ii) intensive, which added subsoiling, aerial broadcast fertilization, and an additional herbicide application. Watershed effects were compared with results from a study on the same small watersheds in 1981, in which two combinations of harvesting and mechanical site preparation without BMPs or fertilization were evaluated. Clearcutting with conventional site preparation resulted in increased nitrogen losses on the small watersheds by about 1 additional kg ha(-1) each of total Kjeldahl nitrogen (TKN) and nitrate-nitrogen (NO(3)-N) in 2003. First-year losses were not significantly increased on the large watershed with a conventional site preparation with BMPs. Fertilization resulted in increased runoff losses in 2003 on the intensive small watersheds by an additional 0.77, 2.33, and 0.36 kg ha(-1) for NO(3)-N, TKN, and total phosphorus, respectively. Total loss rates of ammonia nitrogen (NH(4)-N) and NO(3)-N were low overall and accounted for only approximately 7% of the applied N. Mean loss rates from treated watersheds were much lower than rainfall inputs of about 5 kg ha(-1) TKN and NO(3)-N in 2003. Aerial fertilization of the 5-yr-old stand on another large watershed did not increase nutrient losses. Intensive silvicultural practices with BMPs did not significantly impair surface water quality with N and P.
Spatial Coverage Texas
Description Country affiliation: United States
Author Affiliation: McBroom MW ( Arthur Temple College of Forestry and Agriculture, Stephen F. Austin State University, Box 6109 SFA Station, Nacogdoches, TX 75962, USA.
ISSN 00472425
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Reading ♦ Research ♦ Self Learning
Interactivity Type Expositive
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2008-01-01
Publisher Place United States
e-ISSN 15372537
Journal Journal of Environment Quality
Volume Number 37
Issue Number 1

Open content in new tab

   Open content in new tab
Source: WHO-Global Index Medicus