EFFECTS OF HISTORICAL LAND CLEARING ON ORGANIC MATTER AND NITROGEN LEVELS IN SOILS OF THE FRASER LOWLAND OF BRITISH COLUMBIA, CANADA AND WASHINGTON, U.S.A.

1990 ◽  
Vol 70 (4) ◽  
pp. 583-592 ◽  
Author(s):  
ALAN GOLDIN ◽  
L. M. LAVKULICH

Two soils derived from glacial deposits and one from alluvium were examined for changes in organic matter (OM) and nitrogen levels between 1943 and 1983 across the international boundary in the Fraser Lowland of western North America. Duplicate samples were collected from the upper 0.2 m from 60 randomly selected sites on the five land clearing periods (1943–1955, 1955–1966, 1966–1976, 1976–1983, uncleared) on each of three parent materials: glacial outwash, alluvium, and glacialmarine deposits in the United States and Canada. The land clearing periods were determined from medium scale aerial photographs taken in 1943, 1955, 1966, 1976, and 1983. Cultivation results in a 20% loss of OM after 35 yr on all soils. The largest loss is in the first 15 yr on all soils. Changes in N levels on the three parent materials is irregular. C:N narrows on all soils from about 15:1 to about 12:1. Key words: Organic matter, nitrogen, Fraser Lowland, land clearing, air photo interpretation, parent material

2021 ◽  
Vol 13 (22) ◽  
pp. 4652
Author(s):  
Gabriel Alomar-Garau ◽  
Miquel Grimalt-Gelabert

Historical aerial photographs are valuable sources of climate information. In the present article, a reconstruction of the sea-breezes in Mallorca is described, based on wind-direction interpretation of threshing floors captured by the aerial photographs in 1956–1957 by the United States Army Map Service. These pre-industrial agricultural structures constitute a novel ethnographic proxy of cartographic wind direction at each site. The overall analysis of these directions has made it possible to recreate and model the spatial arrangement of the breezes in Mallorca, and to compare this recreation with that of the existing theoretical-experimental breeze models. The result is a relatively good fit between both recreations, which demonstrates the accuracy of the proposed method. This can be extrapolated to many other aerial-photographed Mediterranean regions prior to full mechanisation of the field.


2014 ◽  
Vol 2 ◽  
Author(s):  
José Navarro Pedreño ◽  
Ignacio Gómez Lucas ◽  
Ignacio Meléndez-Pastor

Estimating the spatial variability of soil properties is significant for evaluating environmental impacts. For example, many soil properties are directly used in the modelling of environmental processes such as global climate change. These aspects have not previously been studied at this level in La Rioja (a region of Spain with a humid Mediterranean environment). The intention of this study was to provide quantitative information on soil assessment and mapping methods for natural soils in a humid Mediterranean environment. The properties considered included: pH and organic matter, calcium carbonate and clay contents. For testing, samples were selected from several different soil types which, in theory, were only affected by pedogenetic processes and had developed on different parent materials. More than half of the samples did not contain any CaCO<sub>3</sub>, while the rest of the samples presented a variety of CaCO<sub>3</sub>, forms, with high percentages being present in certain cases (up to 65% on the surface). It was possible to establish two different areas: one predominantly acidic and the other principally basic. The predominately basic samples were due to the high percentage of carbonate in the parent materials. The clay content on the surface was similar to that in the subsurface layers. Finally, the organic matter contents in the uppermost layers presented average values of 3.9%,with a range of from 0.3 to 17.5%. The major variations in soils were determined by soil type (therefore by soil forming processes), parent material composition, and vegetation type. This study reveals that these methods are useful to determine the spatial distribution of some soil properties in undisturbed soils. The contour maps of soil property variability could be used to improve future sampling designs and management decisions.


Soil Research ◽  
1996 ◽  
Vol 34 (4) ◽  
pp. 545 ◽  
Author(s):  
XJ Wang ◽  
PJ Smethurst ◽  
AM Herbert

Organic carbon or organic matter in acidic Tasmanian soils supporting eucalypt plantations was measured by dry combustion using a LECO CHIN-1000 Analyzer (CT), wet oxidation by the Walkley-Black method (CW&B), and loss-on-ignition (LOI at 375°C). CT and CW&B were highly correlated in 119 surface and subsoil samples, and on average, CW&B provided near complete recovery of CT (97%). Although LOI may have released some structural water from the fine-textured soils, and apart from granite-derived soils which need further study, strong regressions were found between LOI and both CW&B and CT which were specific for either basalt or non-basalt soils. Within the non-basalt soils, parent material had little effect on these relationships, although there were large differences in C concentrations of surface soils between soils of different parent materials. The relationships of CW&B and CT to LOI in the basalt soils were significantly different from those in the non-basalt soils.


2014 ◽  
Vol 2 ◽  
Author(s):  
Raimundo Jiménez-Ballesta ◽  
Marisol S. Andrades ◽  
Álvaro Marín ◽  
Victoria Íñigo ◽  
Juan I. Alonso-Martirena

Estimating the spatial variability of soil properties is significant for evaluating environmental impacts. For example, many soil properties are directly used in the modelling of environmental processes such as global climate change. These aspects have not previously been studied at this level in La Rioja (a region of Spain with a humid Mediterranean environment). The intention of this study was to provide quantitative information on soil assessment and mapping methods for natural soils in a humid Mediterranean environment. The properties considered included: pH and organic matter, calcium carbonate and clay contents. For testing, samples were selected from several different soil types which, in theory, were only affected by pedogenetic processes and had developed on different parent materials. More than half of the samples did not contain any CaCO<sub>3</sub>, while the rest of the samples presented a variety of CaCO<sub>3</sub>, forms, with high percentages being present in certain cases (up to 65% on the surface). It was possible to establish two different areas: one predominantly acidic and the other principally basic. The predominately basic samples were due to the high percentage of carbonate in the parent materials. The clay content on the surface was similar to that in the subsurface layers. Finally, the organic matter contents in the uppermost layers presented average values of 3.9%,with a range of from 0.3 to 17.5%. The major variations in soils were determined by soil type (therefore by soil forming processes), parent material composition, and vegetation type. This study reveals that these methods are useful to determine the spatial distribution of some soil properties in undisturbed soils. The contour maps of soil property variability could be used to improve future sampling designs and management decisions.


Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 628
Author(s):  
Hassan E. Abd Elsalam ◽  
Mohamed E. El- Sharnouby ◽  
Abdallah E. Mohamed ◽  
Bassem M. Raafat ◽  
Eman H. El-Gamal

Sewage sludge is an effective fertilizer in many soil types. When applied as an amendment, sludge introduces, in addition to organic matter, plant nutrients into the soil. When applied for cropland as a fertilizer, the mass loading of sewage sludge is customarily determined by inputs of N and/or P required to support optimal plant growth and a successful harvest. This study aims to examine the changes in organic matter contents and nitrogen forms in sludge-amended soils, as well as the growth of corn and faba bean plants. The main results indicated that there were higher responses to the corn and faba bean yields when sludge was added. Levels of organic carbon in soil were higher after maize harvest and decreased significantly after harvesting of beans, and were higher in sludge amended soils than unmodified soils, indicating the residual effect of sludge in soil. NO3−-N concentrations were generally higher in the soil after maize harvest than during the plant growth period, but this trend was not apparent in bean soil. The amounts of NH4+-N were close in the soil during the growth period or after the maize harvest, while they were higher in the soil after the bean harvest than they were during the growth period. Total nitrogen amounts were statistically higher in the soil during the growth period than those collected after the corn harvest, while they were approximately close in the bean soil. The total nitrogen amount in corn and bean leaves increased significantly in plants grown on modified sludge soil. There were no significant differences in the total nitrogen levels of the maize and beans planted on the treated soil.


2008 ◽  
Vol 88 (5) ◽  
pp. 761-774 ◽  
Author(s):  
J. A. P. Pollacco

Hydrological models require the determination of fitting parameters that are tedious and time consuming to acquire. A rapid alternative method of estimating the fitting parameters is to use pedotransfer functions. This paper proposes a reliable method to estimate soil moisture at -33 and -1500 kPa from soil texture and bulk density. This method reduces the saturated moisture content by multiplying it with two non-linear functions depending on sand and clay contents. The novel pedotransfer function has no restrictions on the range of the texture predictors and gives reasonable predictions for soils with bulk density that varies from 0.25 to 2.16 g cm-3. These pedotransfer functions require only five parameters for each pressure head. It is generally accepted that the introduction of organic matter as a predictor improves the outcomes; however it was found by using a porosity based pedotransfer model, using organic matter as a predictor only modestly improves the accuracy. The model was developed employing 18 559 samples from the IGBP-DIS soil data set for pedotransfer function development (Data and Information System of the International Geosphere Biosphere Programme) database that embodies all major soils across the United States of America. The function is reliable and performs well for a wide range of soils occurring in very dry to very wet climates. Climatical grouping of the IGBP-DIS soils was proposed (aquic, tropical, cryic, aridic), but the results show that only tropical soils require specific grouping. Among many other different non-climatical soil groups tested, only humic and vitric soils were found to require specific grouping. The reliability of the pedotransfer function was further demonstrated with an independent database from Northern Italy having heterogeneous soils, and was found to be comparable or better than the accuracy of other pedotransfer functions found in the literature. Key words: Pedotransfer functions, soil moisture, soil texture, bulk density, organic matter, grouping


1977 ◽  
Vol 18 (79) ◽  
pp. 325-328 ◽  
Author(s):  
W. L. Graf

AbstractEvidence from aerial photographs, maps, and field checks indicates that 319 glaciers lie in cirques of the Rocky Mountains, south of the United States-Canadian border. On a subcontinental scale, the distribution of glaciers is highly clustered, with larger and denser clusters located in the northern Rocky Mountains. Lesser concentrations of small glaciers occur in the southern Rocky Mountains. The total area of glaciers in the Rocky Mountains of the U.S.A. is 78.9 km2.


1964 ◽  
Vol 44 (2) ◽  
pp. 232-236 ◽  
Author(s):  
J. F. Dormaar

Two orthic profiles, widely separated geographically, of each of four parent materials—lacustrine, alluvial–lacustrine, glacial till, and Aeolian—were selected at undisturbed sites within each of the Brown, Dark Brown, and Thin Black soil zones. Material from the Ah and Bm horizons was subjected to solvent extraction, and for each sample the total organic carbon of seven different fractions was determined.The efficiency of the procedure in extracting humus carbon decreased as the total carbon content of the soil increased. Total organic matter, the first humic acid fraction, and the combined total of the three humic acid fractions showed significant differences between soil zones. The only significant separation between all four parent materials was made by the alcohol-benzene fraction. Other parent material separations were possible only following the summation of data of several fractions, such as the three humic acid fractions or the two fulvic acid fractions. A simplification of the procedure in case of soils of one Order and a modification to overcome the impeding effect of increased carbon content are requisite.


Author(s):  
Isaiah Ufuoma Efenudu ◽  
Ehi Robert Orhue ◽  
Ogochukwu Jennifer Ikeh ◽  
Michael Aimiesomon Erhayimwen ◽  
Blessing James

The effectiveness of three different extractants soil mixtures—HCl, HCl + H2S04, and DTPA-TEA, in order to determine Si from soil and the forms of Silicon as influenced by different parent materials under acidic medium. Seven forms of Silicon; namely water soluble, specifically adsorbed, oxides bound, organic matter bound, exchangeable, residual, total viz sequential fractionation. Extractable Si value established in this study was (50.0 mg kg-1), indicating negative effect on plant physiology. The physico-chemical properties decreased significantly with increase in soil depth vs soil parent materials. In addition, the forms of Si in the parent materials decreased in the pattern RES, bound residual fractions > EXC, soluble & exchangeable fractions > OM, organic matter fraction. Among the properties the silt fraction, pH & OM significantly and positively correlated with the forms of silicon, with negative correlation vs clay which maybe due to silicon adsorption by clayey fraction of the soil (redox). Therefore the soil maybe be maintained and conserved for farming activities.


Author(s):  
Alyssa M. Neir ◽  
Michael E. Campana

To deal with boundary and transboundary water issues along their border, the United States and Mexico established the International Boundary and Water Commission (IBWC) in 1889. Initially dealing only with surface water flows, its flexibility permitted changes such that groundwater and water quality issues could be addressed. In 1994, the U.S., Mexico, and Canada adopted the North American Free Trade Agreement (NAFTA) primarily to facilitate trade, but which can govern water as an article of commerce. Both NAFTA and the IBWC have been instrumental in promoting peaceful solutions to water issues. The article examines three cases: (1) Mexico's protesting of a U.S. plan to line the All-American Canal on the Mexico-California; (2) the underdelivery of Mexican Rio Grande water to the U.S. state of Texas; and (3) the case of an aquifer entirely within Mexico whose supply is being stressed because of a shift in agricultural production prompted by NAFTA. The article concludes that both countries should: (1) develop a more formal system for groundwater issues and (2) exercise vigilance with respect to NAFTA's ability to treat water solely as an economic good.


Sign in / Sign up

Export Citation Format

Share Document