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1.
Abstract

This study aimed to clarify pedogenetic processes and classification of yellowish Brown Forest Soils according to the Classification of Forest Soils in Japan and the Yellow Brown Forest soils according to the Unified Soil Classification System of Japan in the warm and cool temperate forest of Kyushu district, Japan. In addition, the study aimed to clarify a problem with the Unified Soil Classification System of Japan. Thirty-six soil profiles of Brown Forest Soils, including 13 yellowish Brown Forest Soils and 15 Yellow Brown Forest soils, were compared with regard to their chemical properties and the relationship with climatic conditions was assessed. The yellowish Brown Forest Soils had thin A horizons, low pH and low levels of free oxides in the B horizons, and a low amount of silica and a high aluminum and iron to silica ratio. These features were related to the paleo reddish weathering. The immaturely developed A horizon of the yellowish Brown Forest Soils was caused by these weathered, low-activity substances. The Yellow Brown Forest soils had low levels of active iron oxides and a low activity ratio of free iron oxides compared with the Haplic Brown Forest soils in the same thermal climatic conditions. The activity ratio of free iron oxides was correlated to mean annual air temperature with the carbon stocks and with many other chemical properties. Accordingly, classification of Brown Forest Soils was clearer according to thermal climatic conditions. The activity ratio of free iron oxides can become an effective index that distinguishes Yellow Brown Forest soils under warm temperate lucidophyllous forest and Haplic Brown Forest soils under cool temperate broad-leaved deciduous forest with considerable vertical soil zonality.  相似文献   

2.
《Applied soil ecology》2008,38(3):202-214
The objectives of our research were to evaluate the impact of organic, sustainable, and conventional management strategies in grower fields on soil physical, chemical, and biological factors including soil microbial species and functional diversity and their effect on the Basidiomycete plant pathogen Sclerotium rolfsii, causal agent of Southern blight. Soils from 10 field locations including conventional, organic and sustainable farms were sampled and assayed for disease suppressiveness in greenhouse assays, and soil quality indicators. Soils from organic and sustainable farms were more suppressive to Southern blight than soils from conventional farms. Soils from organic farms had improved soil chemical factors and higher levels of extractable C and N, higher microbial biomass carbon and nitrogen, and net mineralizable N. In addition, soil microbial respiration was higher in soils from organic than sustainable or conventional farms, indicating that microbial activity was greater in these soils. Populations of fungi and thermophiles were significantly higher in soils from organic and sustainable than conventional fields. The diversity of bacterial functional communities was also greater in soils from organic farms, while species diversity was similar. Soils from organic and sustainable farms had improved soil health as indicated by a number of soil physical, chemical and biological factors and reduced disease.  相似文献   

3.
Samples of upland-farm surface soils (0–10 em in depth) belonging to various great soil groups were collected in 28 upland sites in Thailand during the rainy season.

Among the microbes related to the transformation of nitrogen, namely ammonifiers, ammonia oxidizers, nitrite oxidizers and denitrifiers, the count of denitrifier showed the maximum value amounting to 104 to 105 per 1 g of dry soil, followed byammonifier. The population level of nitrogen-fixing blue green algae was unexpectedly high, being 103 to 101

The microbial counts in Brown Forest Soils, Rendzinas and Grumusols with high content of organic matter, available phosphorus and exchangeable potassium tended to be high.

Non-calcic Brown Soils, Reddish Brown Lateritic Soils, Alluvial Soils, Red-Yellow Podzolic Soils and Gray Podzolic Soils which lack in some nutrients showed intermediate levels of microbial populations, while the counts of nitrogen-fixing blue green algae in Alluvial Soils and those of denitrifier in Red-Yellow Podzolic Soils were markedly high. In the case of Low Humic Gley Soils and Regosols with low content of organic matter, available phosphorus and available potassium, the population of microbes was generally small.

The relationship between the organic matter content and the microbial population of soils was positively significant at 0.1 % level only in the case of fungal population (r=0.551), while the relationship between the available phosphorus content and the microbial population was positively significant at 0.1% level only in the case of Azotobacter (r=0.682).

The relationships between the total nitrogen, the exchangeable potassium, the amount of NH4+-N, the amount NO2 --N, or the amount of NH4 +-N+NO2 --N and each microbial population were not significant in any microbial groups.

The count of denitrifiers in upland farm soils of Thailand was 9 times as high as that in non-volcanic upland-farm soils of Japan and was 23 times higher than that in volcanic soils though large variations were seen among the great soil groups of Thailand. Conversely, the population of non-spore-forming nitrite oxidizers in the upland farm soils of Thailand was 1/100 that in non-volcanic soils of Japan and 1/280 that in volcanic soils. In the case of Azotobacter, the count in upland farm soils of Thailand averaged 2,800 per 1 g of dry soil. while that in non-volcanic upland farm soils of Japan was 77 on the average.

The ratio of aerobic bacteria to actinomycetes in upland farm soils of Thailand was 2.31, while that of non-volcanic soils of Japan was 7.28.  相似文献   

4.
Remoulded soils compress more rapidly than undisturbed soils at the same initial density and water content. Soils with larger particles compress more rapidly than those with smaller particles. Soils compress more slowly when they are more densely packed. Soils expand more slowly than they compress between the same two pressures. Implications of these results are that soils which are not tilled would be less susceptible to compaction, and that tractors and other vehicles would cause less compaction when travelling at higher speeds.  相似文献   

5.
6.
Ten soil profiles from the agricultural areas in Saudi Arabia were investigated for their mineralogical properties and some general characteristics. It was found that the soils of the eastern region were Torrifluvents and Gypsiorthids, coarse in texture with high salt, gypsum and carbonate contents. Soils of the central region were found to be Torriorthents, Torrifluvents and Torripsamments, medium to coarse in texture with smaller amounts of gypsum and salt than soils in the east. Soils of the western region were Haplargids with minor amounts of carbonate and salt. Carbonate, quartz and gypsum were found to be the main constituents of the sand and silt fractions in soils of the eastern region, while quartz, carbonate and feldspars dominated the sand and silt in the central region. The sand and silt fractions of soils in the west contained mainly quartz, feldspars, hornblende and mica. Palygorskite dominated the clay fractions of soils in the east, while kaolinite was found to be dominant in the central region, and kaolinite, smectite and mica in the west. The mineral composition of the soils was affected by the rocks from which they were derived. Igneous and metamorphic rocks of the Arabian Shield affected the soils in the west, while sedimentary rocks had great influence on soils of the central and eastern regions.  相似文献   

7.
Journal of Soils and Sediments - Purple paddy soils cover about 66% of the paddy soils in Sichuan Basin. Complex interactions made the effects of potassium fertilizer application on NH4+ adsorption...  相似文献   

8.
Ammonium chemistry in surface soils collected from major soil series of Bangladesh was studied in terms of quantity-intensity (Q/I) relationship. Soils were classified according to physiography and parent materials; calcareous floodplain soils were dominated by mica and smectite, while non calcareous floodplain soils, terrace soils, and hill soils were dominated by mica or kaolinite and lacked smectite as a major clay mineral. Different Q/I parameters were obtained between soils of smectitic and non-smectitic types. Soils of smectitic type had a high potential buffering capacity which kept the equilibrium activity ratio at a low and fixed level.. The content of labile ammonium was high and estimated to increase with increasing addition of NH4 +. In contrast, soils of non-smectitic type with a low potential buffering capacity showed a considerable variation of both the equilibrium activity ratio and labile ammonium content, as affected by the application of NH4 +. Based on the ammonium chemistry, expected N-fertilizer application was compared with the prevailing application method.  相似文献   

9.
Journal of Soils and Sediments - This study assessed soils from 36 parks and gardens (Vigo City, NW of Spain) where there are different degrees of traffic intensity and activity. The soils were...  相似文献   

10.
Ren  Jun  Mi  Xuan  Tao  Ling 《Journal of Soils and Sediments》2021,21(2):1001-1009
Journal of Soils and Sediments - The palygorskite-coated nanoscale zero-valent iron (PAL-nZVI) was synthesized and used in the remediation of Cd-contaminated soils. The function of PAL-nZVI on...  相似文献   

11.
Journal of Soils and Sediments - The content, source, and spatial distribution of heavy metals in soils are necessary to establish quality standard on a regional level, to assess the potential...  相似文献   

12.
Journal of Soils and Sediments - The aim of this study is the assessment of Ni, Mn, Cd, Cu, Pb, Cr and Zn accumulation by different herbaceous species and soils on the technogenic areas around...  相似文献   

13.
The characteristics are outlined of freely drained soils, transitional in location, morphology and chemistry between modal Brown Earths and Peaty Podzols, which occur widely in western and upland Britain. They have been classified in a number of ways, which are discussed with reference to a review of American and European treatment of Brown Podzolic Soils. Although precise definition in terms of chemistry is not possible, evidence supports the continued distinction of such soils as Brown Podzolic Soils (or Sols Bruns Podzoliques) considered as a sub-group of Podzolized Soils.  相似文献   

14.
(pp. 59–66)
In order to understand the detailed soil distribution of a terrace with a diluvial deposit, the method to draw a large-scale soil map was studied in Urausu Town of Sorachi district by combinig soil survey and digital elevation data for a 10 m grid.
The results are summarized as follows:
  • 1) 

    From a soil survey, soils in the research area were classified into 3 soil series groups according to Classification of Cultivated Soils in Japan, Third Approximation, which were Skeletal Terrace Brown Forest Soils, Fine-textured Aquic Brown Forest Soils and Fine-textured Haplic Gray Upland Soils. In addition, Fine-textured Haplic Gray Upland Soils · were classified into 2 categories based on the abundance of gravel in the subsoil.

      相似文献   

15.
Yu  Sumei  Bai  Xin  Liang  Jinsong  Wei  Yingnan  Huang  Siqi  Li  Yue  Dong  Liying  Liu  Xuesheng  Qu  Juanjuan  Yan  Lei 《Journal of Soils and Sediments》2019,19(3):1064-1076
Journal of Soils and Sediments - To remedy the heavy metal polluted soils, microbe-assisted phytoextraction was employed to remove Pb from soils. The Pb contents, soil enzyme activities, and...  相似文献   

16.
Journal of Soils and Sediments - To evaluate the ecological risk, physico-chemical properties, and the impact of anthropogenic sources on permanent eighteen samples of grass vegetation soils (PGVS)...  相似文献   

17.
J. Dan  A. Singer 《Geoderma》1973,9(3):165-192
The soils of the Golan basaltic plateau were surveyed and analyzed. Soils on uneroded plateaus range from montmorillonitic calcareous Reddish Brown Grumusols in the semi-arid areas through noncalcareous Brown Grumusols in the sub-humid areas to Brown and Red Mediterranean Soils with typical argillic horizons and dominance of kaolinitic clay in the humid parts of this region. Protogrumusols and basaltic Lithosols are found in eroded places. Volcanic cone soils in the humid Golan parts range from tuffic Regosols on the youngest cones and most eroded areas through tuffic Red Mediterrranean silty clay loam and silty loam on less eroded areas to tuffic Red Mediterranean clays on the older volcanic eruption sites and comparatively stable slopes.The weathering of the basalt is comparatively very slow, especially in the drier upland areas of the southern Golan. The weathering of the pyroclastic materials, on the other hand is fast, due to the great internal surface of this parent material.The various soils exhibit different leaching stages. A gradual disappearance of lime, decrease in pH values, increase in exchangeable H+ and a shift from montmorillonite clay dominance to kaolinite and similar clay types expresses the increase in the leaching degree from the dry areas to the moist ones.The textural profile of Golan soils depend on clay content and type. A soil sequence commencing with self-mulching Grumusols through various intermediate types to typical ABC Red and Brown Mediterranean Soils may be distinguished along climatic, time and drainage gradients.  相似文献   

18.
Yuan  Qiusheng  Wang  Peifang  Wang  Chao  Chen  Juan  Wang  Xun  Liu  Sheng 《Journal of Soils and Sediments》2021,21(10):3515-3527
Journal of Soils and Sediments - The construction of large dams submerges riparian soils within reservoirs. However, little is known about the influence of water submergence on metal(loid)...  相似文献   

19.
The Gloldnaya steppe has large areas of fertile sierozem soils that are important for crop production and its accompanying economic development. The soils are fertile loams, but because of the steppe's dry environment, they need to be irrigated. Our objective was to study irrigation management of cotton production on sierozem soils in southern Kazakhstan. From 2006 to 2008, we grew irrigated cotton on low, moderately, and highly saline sierozem soils in the South Kazakhstan Oblast. Soils were irrigated to reduce salinity and improve growth. Yields increased with reduced salinity especially because the highly saline soil could not support growth every year and because it had 33 to 40% less yield when cotton was grown on it. Soils were managed with multiple tillage and cultivations by machinery and hand, which maintained low bulk densities near the surface and a tillage pan at about the 30-cm depth. Future management improvements include fewer tillage operations, which would decrease energy needs and compaction. Reduced upstream salinity would reduce preplanting irrigation needs.  相似文献   

20.
Journal of Soils and Sediments - The aims of the current study were to (1) examine the interactive effects of biochar addition and differently textured soils (clayey and sandy soils) on nutrient...  相似文献   

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