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Effects of Hydrology and Field Management on Phosphorus Transport in Surface Runoff

Journal Articles & Books
Dezembro, 2009

Phosphorus (P) losses from agricultural landscapes arise from the interaction of hydrologic, edaphic, and management factors, complicated by their spatial and temporal variability. We monitored sites along two agricultural hillslopes to assess the effects of field management and hydrology on P transfers in surface runoff at different landscape positions.

Does cultivation influence the content and pattern of soil proteins

Journal Articles & Books
Dezembro, 2011
Irã

Proteins comprise one of the largest N inputs to soils. There is, therefore, a need to investigate the factors involved in the inputs and fate of proteins in soil. While land use management is expected to influence the amount and diversity of soil proteins, the responses of protein as a source of mineralizable N to land use changes have not yet been studied. We hypothesized that extractable soil protein could be a sensitive indicator in evaluating the effect of stress in ecosystem.

Evaluation of two soil carbon models using two Kenyan long term experimental datasets

Journal Articles & Books
Março, 2007
Quênia
África Oriental

RothC and Century are two of the most widely used soil organic matter (SOM) models. However there are few examples of specific parameterisation of these models for environmental conditions in East Africa. The aim of this study was therefore, to evaluate the ability of RothC and the Century to estimate changes in soil organic carbon (SOC) resulting from varying land use/management practices for the climate and soil conditions found in Kenya.

Integrated analysis of landscape management scenarios using state and transition models in the upper Grande Ronde River Subbasin, Oregon, USA

Journal Articles & Books
Dezembro, 2007
Estados Unidos

We modeled the integrated effects of natural disturbances and management activities for three disturbance scenarios on a 178,000 ha landscape in the upper Grande Ronde Subbasin of northeast Oregon. The landscape included three forest environments (warm-dry, cool-moist, and cold) as well as a mixture of publicly and privately owned lands. Our models were state and transition formulations that treat vegetation change as probabilistic transitions among structure and cover types.

Discriminating the effects of agricultural land management practices on soil fungal communities

Journal Articles & Books
Dezembro, 2007

The structure of fungal communities was examined in soil subjected to 5 years of different agricultural land management and tomato production practices. Length heterogeneity polymerase chain reaction (LH-PCR) of fungal rDNA internal transcribed spacer-1 (ITS-1) regions was used to create genomic fingerprints of the soil fungal communities.

Spatial dependence of predictions from image segmentation: A variogram-based method to determine appropriate scales for producing land-management information

Journal Articles & Books
Dezembro, 2010

A significant challenge in ecological studies has been defining scales of observation that correspond to the relevant ecological scales for organisms or processes of interest. Remote sensing has become commonplace in ecological studies and management, but the default resolution of imagery often used in studies is an arbitrary scale of observation. Segmentation of images into objects has been proposed as an alternative method for scaling remotely-sensed data into units having ecological meaning.

Inorganic nitrogen, sterols and bacterial source tracking as tools to characterize water quality and possible contamination sources in surface water

Journal Articles & Books
Dezembro, 2012
Canadá

The effects of agricultural activities on stream water quality were assessed by nitrogen analysis, further investigated by gas chromatography mass spectrometry (GC-MS) sterol analysis (including chemometric analysis), and characterized by bacterial source tracking (BST). Surface water samples were collected from five sites, throughout the agriculturally-influenced Nathan Creek watershed, British Columbia, Canada and a nearby control site between October 2005 and March 2006.

Feature Extraction Techniques for Measuring Piñon and Juniper Tree Cover and Density, and Comparison with Field-Based Management Surveys

Journal Articles & Books
Dezembro, 2011

Western North America is experiencing a dramatic expansion of piñon (Pinus spp.) and juniper (Juniperus spp.) (P-J) trees into shrub-steppe communities. Feature extracted data acquired from remotely sensed imagery can help managers rapidly and accurately assess this land cover change in order to manage rangeland ecosystems at a landscape-scale.

The management and classification of the typical soils of the Yıldız Forest Ecosystem

Policy Papers & Briefs
Dezembro, 2009
Turquia

The soils of the Yıldız Mountain, namely Entisols, Mollisols, Inceptisols, Ultisols, and Spodosols, from Poyralı, Yeniceköy, Demirköy and northwest of Igneada that were developed on calcareous sandy sediments, chlorite schists, Pliocene sediments and alluvial materials were studied in this paper.