Soil is a complicated system whose components and mechanisms are complex and difficult to be fully excavated and comprehended. Nitrogen is the key parameter supporting plant growth and development, and is the material basis of plant growth as well. An accurate grasp of soil nitrogen information is the premise of scientific fertilization in precision agriculture, where near infrared sensors are ...

Population’s exponential growth along with drought has increased water resources limitation, especially in arid and semi-arid area. Therefore, the use of non-conventional water is an important tool for water resource management. If unconventional water has no negative impact on soil properties and water, it can be used for irrigation coupled with desertification projects. So, this paper tries t...

Population’s exponential growth along with drought has increased water resources limitation, especially in arid and semi-arid area. Therefore, the use of non-conventional water is an important tool for water resource management. If unconventional water has no negative impact on soil properties and water, it can be used for irrigation coupled with desertification projects. So, this paper tries t...

Root responses to differences in availability of nitrogen and soil water were studied in loblolly pine (Pinus taeda L.) seedlings grown in monoculture and in competition with sweetgum (Liquidambar styraciflua L.) or crab grass (Digitaria spp.). Rhizotron cells were maintained at high soil water availability (approximately -0.1 MPa) or subjected to three dry-down cycles to low soil water availab...

In this study, an experiment under controlled conditions was carried out to determine the effects of secondarytreated sewage effluent (STSE) application on soil nitrogen concentrations (mineral and total), total carbon and soil pH. The soil and STSE used were collected at Lins, São Paulo State, Brazil. A completely randomized design was used, in completed factorial 4x11 (weekly application rate...

The soils of the central Oregon pumice plateau are relatively young and infertile, yet support an array of plant diversity and growth in the region’s pine forests. Whether these coarsetextured, pumice and ash soils are resilient to forest disturbance is not well understood. We present results from a long-term experiment that examined changes in soil quality in response to combinations of thinni...

The effects of forest harvest on stream-water quality and nitrogen cycling were examined for a redwood/Douglas-fir ecosystem in the North Fork, Caspar Creek experimental watershed in northern California. Stream-water samples were collected from treated (e.g., clearcut) and reference (e.g., noncut) watersheds, and from various locations downstream from the treated watersheds to determine how far...

The variability in the net ecosystem exchange of carbon (NEE) is a major source of uncertainty in quantifying global carbon budget and atmospheric CO2. Soil respiration, which is a large component of NEE, could be strongly influential to NEE variability. Vegetation type, landscape position, and site history can influence soil properties and therefore drive themicrobial and root production of so...