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11.
Hamza Mohieddinne Boris Brasseur Emilie Gallet-Moron Jonathan Lenoir Fabien Spicher Ahmad Kobaissi Hélène Horen 《Land Degradation u0026amp; Development》2023,34(5):1558-1569
To ensure sustainable forest management, the assessment and monitoring of soil compaction and rutting are essential. Here, we used airborne light detection and ranging-derived digital terrain model (LiDAR-derived DTM), available for the forest of Compiègne in northern France, to compute a spatial index of soil rutting. Following an environmental systematic sampling design, we selected 45 plots representative of the forest stand conditions where we subsequently extracted information from the DTM to compute the cumulative length of ruts (CLR). To assess the quality of this LiDAR-derived index, we related the CLR index to in-situ soil and vegetation parameters such as soil texture, soil pH, and understory plant species composition. Floristic surveys were carried out across all 45 plots to generate plant species response curves along the CLR gradient. We found soil texture, soil type, and soil pH to be important determinants of CLR. For instance, CLR was the highest in soils with the highest clay content. A total of 22 out of the 94 understory plant species we analyzed showed a significant response curve along the CLR gradient. Most important, the occurrence probability of species associated with wet soils and stagnant waters (e.g., Juncus effusus), like those found in ruts, increased with CLR. Other species associated with dry soils (e.g., Hedera helix) showed a negative response curve along the CLR gradient. In conclusion, the proposed index (CLR) has proven useful to remotely assess soil compaction and rutting after logging operations. 相似文献
12.
《Communications in Soil Science and Plant Analysis》2012,43(3):187-195
Abstract A field experiment was conducted to determine whether Zn applied for pathogen control could accumulate to a level which would be toxic to snapbeans, cucumbers, or corn. Zinc sulfate (ZnSO4) was applied at rates varying from 0 to 363 kg Zn/ha on a Flainfield loamy sand to approximate 3, 9, 27 and 81 years of fungicidal treatment. Even at the high rate of Zn, yields of snapbeans, cucumbers, or corn generally were not reduced. As rates of applied Zn increased, there was a corresponding increase in the level of Zn in the leaf tissue of all crops grown. At the high Zn rate, snapbean and cucumber leaf tissue accumulated over 350 ppm Zn. Available soil Zn was extracted with 0.1N HCl, EDTA, or DTPA. Highly significant correlations were observed between the Zn removed by each extractant and plant tissue Zn, thus, indicating that the various extractants were equally effective in predicting Zn uptake. Very little downward movement of Zn was observed. Two and one‐half years after application, the Zn had leached to a depth of only 30 cm in the soil profile at the higher Zn rates. These data indicate that application of Zn‐containing fungicides and bactericides should not cause a Zn toxicity problem on the Plainfield sand in the foreseeable future. 相似文献
13.
《Communications in Soil Science and Plant Analysis》2012,43(19-20):2635-2646
Abstract Assessing base cation [calcium (Ca2+), magnesium (Mg2+), potassium (K+)] fluxes is necessary for determining ecosystem stability. This study was conducted in the Osinovka River catchment located on the Khamar‐Daban Ridge, South Baikal, which is characterized by high precipitation (more than 1700 mm per annum). The contributions of different ecosystem components such as atmospheric deposition, soil exchange pool, minerals, vegetation, surface water, and groundwater into the total base cations flux were evaluated, combining the strontium isotope approach and budget study. Results show the leading role of atmosphere in ecosystem supply with base cations. The atmosphere contributes 48% of total base cations flux, and its contributions to plant‐available nutrition pools of both organic and mineral horizons are equal to 50%. This makes the vitality of vegetation, to a great extent, dependent on the stability of atmospheric chemistry. 相似文献
14.
H. Aïchi Y. Fouad D. Causeur C. Walter 《Communications in Soil Science and Plant Analysis》2020,51(9):1253-1267
ABSTRACT Many factors could influence simultaneously soil spectra. We aimed to study the single effect of organic carbon and total iron in soil visible and short-wave near-infrared spectra and to quantify their contents. Two datasets of soil mixture samples were prepared by mixing, in various fractions, an organic carbon-rich material with a total iron-rich material and then with a total iron-poor material. For these two datasets, contents in organic carbon are quite similar but contents in total iron are significantly different. Results show that samples of the same dataset have the same overall spectral shape. Organic carbon has a decreasing effect that affects the whole spectral range without showing any specific absorption peaks. By contrast, total iron has specific absorption peaks. Spectra of the second dataset characterized by soil mixtures with higher total iron contents were more compact within the spectral bands 400–440 and 920–950 nm. Besides, continuum removal enables to exaggerate absorption peaks of wavelengths linked to total iron content. Partial Least Squares Regression (PLS R) models of both total organic carbon and total iron assign high coefficients to the wavelengths that are considered relevant and conversely low coefficients to those that are considered irrelevant. Both organic carbon content and total iron content were well predicted. For these models, coefficients of determination were superior to 0.9 and RMSE was closed to zero. The global models calibrated on all the samples demonstrated that PLS R was able to integrate sample heterogeneity. 相似文献
15.
16.
Neither the phosphorus (P)‐rich soils in urban areas nor their environmental implications have been adequately studied. This study investigated soils of typical urban function zones in Nanjing/China, like park, residential areas, school yards, campus as well as suburb vegetable land and garbage filling sites, and meantime ground water in situ. Typical soils were also experimentally leached for P leaching evaluation. All studied soils were enriched with P with enrichment ratios varying from 2 to 10 for total P and 5 to 22 for NaHCO3‐extractable P, as compared with the original parent soils. The C : P ratios also indicated strong enrichment of P in urban soils. In urban areas the maximum P layer appeared as buried under different depth while in suburban soils as epipedon. The various morphology of P distribution suggested different soil formation patterns, which were related to the land use history. Groundwater P was significantly correlated with the maximum extractable P content of P in soil profiles and even better with the weighted average P content of the whole profile or P content of the soil layer at or close to groundwater table. Dissolved P in experimental leachate was comparable with that of groundwater but higher than environmentally acceptable level. Furthermore, there was a significant correlation between solution P and different extractable P forms of the studied soils. Simple P tests can provide an evaluation of the potential risk of urban soils in discharging P to water system. 相似文献
17.
18.
Relation of soil organic matter concentration to climate and altitude in zonal soils of China 总被引：1，自引：0，他引：1
With a total of 886 data sets distributed in different regions of China, the relation of soil organic matter (SOM) concentration to climate and altitude was investigated. These data sets were obtained from the 2nd National Soil Survey of China that was completed in early 1980s. According to climate gradient and vegetation community succession, six geographical regions, including eastern, southern, northern, northeastern, northwestern and southwestern China, were divided to identify the key factors regulating surface SOM concentration in different geographical regions. Correlation analysis indicates that surface SOM concentration is in general negatively correlated with annual mean temperature (T) and positively correlated with annual mean precipitation (P) and altitude (H). A further investigation suggested that multiple regression models with different combination of T, P and H could explain 41.5%–56.2% of the variability in surface SOM concentration for different geographical regions, while the driving variables are different. Variables of T and P determined surface SOM concentration in northern, northeastern and northwestern China. In eastern and southern China, variables of P and H are key factors regulating surface SOM concentration. Surface SOM concentration in southwestern China is determined by a linear combination of T, P and H. 相似文献
19.
《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2012,62(8):206-216
Abstract Erosion and loss of soil is a large problem for water quality all over the world. Mitigation measures need to target the main sources of erosion at the right scale. For many areas there is still great uncertainty at the catchment level as to what are the main sources of erosion and how they can be managed. The objective of this article was to investigate the effect of tillage on soil losses at the field and catchment scale. Long-term monitoring data (20 years) from a catchment and a nested field site in the south eastern Norway were used. Results from the Vandsemb field showed that soil losses were on average 940 kg ha−1 yr−1 for years (n=5) when the field was autumn ploughed and 174 kg ha−1 yr−1 for years (n=8) when the field was not tilled in autumn. For the total monitoring period, surface soil losses were 330 kg ha−1 yr−1, whereas sub-surface soil losses were 130 kg ha−1 yr−1. Total phosphorus and dissolved reactive phosphorus (DRP) losses in surface runoff were 460 g ha−1 yr−1 and 150 g ha−1 yr−1, respectively and in sub-surface runoff they were 530 g ha−1 yr−1 and 270 g ha−1 yr−1, respectively. At the catchment scale, no relationship was found between the soil tillage on agricultural fields and the variation in losses of suspended sediments (SS) at the catchment scale. The average losses at Mørdre were for suspended sediments 2140 kg ha−1yr−1, for total phosphorus 2320 g ha−1 yr−1, and for DRP 240 g ha−1 yr−1. Weather conditions, especially during winter, were important for the temporal variation in losses of SS at both sites. Soil losses from the Mørdre catchment were approximately five times higher than from the Vandsemb field. The study findings suggest that changes in soil tillage were not the dominating cause of variations in loss of SS from the catchment, although these changes were important at the field scale. 相似文献
20.