A study was conducted to determine the characters of soil structure in different water and soil conservation forests in Keshan County,northwest of Heilongjiang Province,China.The soil bulk density,the ratio of non-cap...A study was conducted to determine the characters of soil structure in different water and soil conservation forests in Keshan County,northwest of Heilongjiang Province,China.The soil bulk density,the ratio of non-capillary porosity and capillary porosity(NCP/CP),and the generalized soil structure index(GSSI) were measured for Fraxinus mandshurica,Larix gmelini,Pinus sylvestris var.mongolica,and Picea koraiensis plantations as well as the abandoned land(as control) adjacent to the forests in typical black soil region.Results show that at soil depth of 0–30cm,the soil bulk density of F.mandshurica forest and L.gmelini forest was lower than that of P.sylvestris var.mongolica forest and P.koraiensis forest,with the relative decrease of 8.04%–11.01%.The soil bulk density of L.gmelini forest was significantly different from that of the P.sylvestris var.mongolica forest and P.koraiensis forest.The NCP/CP values of the four types of plantations were all higher(59.75%–128.82% relatively) than that of abandoned land(p〈0.05),indicating that the soil aeration and permeability under forest were enhanced,especially under L.gmelini forest.GSSI values of the four types of forests were also relatively higher(2.98%–4.36%) than abandoned land(p〈0.05),indicating that those soil and water conservation forests,especially the F.mandshurica forest and P.koraiensis forest,can promote soil condition to approximate ideal soil structure.The result of this study can provide theoretical basis for scientifically evaluating the effects of vegetation restoration on soil quality in typical black soil region.展开更多
In order to provide some preliminary recommendations for the sustainable use and management of croplands, land suitability evaluation for crops was carried out in Shouyang County which partly locates on the Loess Plat...In order to provide some preliminary recommendations for the sustainable use and management of croplands, land suitability evaluation for crops was carried out in Shouyang County which partly locates on the Loess Plateau suffering severe soil and water erosion and is characterized by ecological vulnerability and semi-arid climate. Here, land suitability for 4 local crops of maize, wheat, sorghum and millet under 2 cultivation senarios of tradition and mechanization was evaluated by a upscaling approach. The upscaling was implemented in a land form hierarchy which was composed of land unit, land facet and land site at 3 spatial levels. The IAO land suitability evaluation model for crops was revised by applying a meteorological revision index. Rresults showed that a polarized phenomenon occurred, which means that the most suitable class (S1) and the most unsuitable class (N2) were predominant in acreage percentage for all the 4 crops. Maize, millet and wheat were relatively more adaptive to be grown and should be ploughed in the traditional mode. Hence, future cropland use policy should pay more attention to the conversion of arable land to forestland and grassland in unsuitable areas and to more investment for agricultural production in suitable regions, and it is necessary to balance the relationship between the livelihood of local farmers and environmental protection to maintain a healthy and stable ecosystem.展开更多
[Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil product...[Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil productivity of paddy field from the cultivation aspect.[Method] Taking kenjiandao 10 as the material,the variation laws of root weight,soil physical and chemical characteristics,soil enzyme,straw decomposition rate,soil temperature,microorganism of rice under the planting patterns of water-saving pro...展开更多
[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experi...[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experiment in Jinan of Shandong Province was selected and the results of soil nutrient and crop yield in 1984, 1987, 1988, 1989, 1990, 2001, 2005, 2006, 2007 and 2010 were measured and collected. In this study, five treatments: CK, NP, NK, PK and NPK of the located experiment were selected. [Result] The three types of soils in wheat yields decreased signifi- cantly in the first several years and in 2006. Wheat yields of the treatments with P fertilizers were obviously higher than those without P fertilizers; it was shown that phosphorus is the primary nutritional factor for high-yielding of wheat. The highest yield is from cinnamon soil, followed by that from brown soil, and the lowest pro- duction is from fluvo-aquic soil. Under the same fertilization, the influence of other factors on wheat yield of brown soil is the smallest, while cinnamon soil is vulnera- ble to the influence of external conditions, resulting in larger fluctuation of annual wheat yield. The alkali-hydro nitrogen contents of three kinds of soils first de- creased, then raised, and at last reduced apparently. Since 2007, the change of al- kali-hydro nitrogen content appeared rebounded. The available P contents of no- phosphorus treatments decreased over time while those of the treatments with P fertilizers increased at first, then decreased, and after that kept relatively stable. The available K contents of no K treatments decreased slowly. The treatments of PK and NK had higher available K content than NPK treatment. [Conclusion] Thus, it is an effective fertilization measure to improve the wheat yield by supplying reasonable phosphate fertilizer and nitrogen fertilizer and making up potassium fertilizer.展开更多
The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards...The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation.展开更多
A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004....A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004. Results indicated that the total soil respiration, root-severed soil respiration and the root respiration followed a similar seasonal trend, with a high rate in summer due to wet and high temperature and a low rate in spring and autumn due to lower temperature. The mean rates of total soil respiration, root-severed soil respiration and root respiration were 4.44, 2.30 and 2.14 μmol.m^-2.s^-1, respectively during the growing season, and they were all exponentially correlated with temperature. Soil respiration rate had a linear correlation with soil volumetric moisture. The Q10 values for total soil respiration, root-severed soil respiration and root respiration were 2,82, 2.59 and 3. 16, respectively. The contribution rate of root respiration to the total soil respiration was between 29.3% and 58.7% during the growing season, indicating that root is a major component of soil respiration. The annual mean rates of total soil respiration, root-severed soil respiration and root respiration were 1.96, 1.08, and 0.87 μmol.m^-2.s^-1, or 741.73 408.71, and 329.24 g.m^-2.a^-1, respectively. Root respiration contributed 44.4% to the annual total soil respiration. The relationship proposed for soil respiration with soil lemperature was useful for understanding and predicting potential changes in Changbai Mountain B. platyphylla forest ecosystem in response to forest management and climate change.展开更多
In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different...In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different depths were significantly (p<0.05) higher in Meadow alpine tundra vegetation than that in other vegetation types; the soil C (including inorganic carbon) concentrations at layer below 10 cm are significantly (p<0.05) higher than at layer of 1020 cm among the different vegetation types; the spatial distribution of soil N concentration at top surface of 0-10 cm depth was similar to that at 1020 cm; the soil P concentrations at different depths were significantly (p<0.05) lower at Lithic alpine tundra vegetation than that at other vegetation types; soil K concentration was significantly (p<0.05) higher in Felsenmeer alpine tundra vegetation and Lithic alpine tundra vegetation than that in Typical alpine tundra, Meadow alpine tundra, and Swamp alpine tundra vegetations.. However, the soil K had not significant change at different soil depths of each vegetation type. Soil S concentration was dramatically higher in Meadow alpine tundra vegetation than that in other vegetation types. For each vegetation type, the ratios of C: N, C: P, C: K and C: S generally decreased with soil depth. The ratio of C: N was significantly higher at 010 cm than that at 1020 cm for all vegetation types except at the top layer of the Swamp alpine tundra vegetation. Our study showed that soil C and nutrients storage were significantly spatial heterogeneity.展开更多
[Objective] The aim was to evaluate the eco-geochemical characteristics and geochemistry conditions of root soil in muskmelon planting area, evaluate the soil environment quality in Hetao irrigation area and provide s...[Objective] The aim was to evaluate the eco-geochemical characteristics and geochemistry conditions of root soil in muskmelon planting area, evaluate the soil environment quality in Hetao irrigation area and provide scientific basis for the musmelon planting in this area. [Method] Root system soil sample and plow pan sample were collected from the main muskmelon planting area in Hetao irrigation area, so as to analyze the contents of heavy metal elements. By comparing with the Soft Environmental Quality Standard (GB15618-1995), the research explored whether the heavy metal elements in root system met the national standard. [Result] Heavy metal elements in root system soil had the maximum content in recession area of Yellow River, followed by saline soils. The content of heavy metal elements in chestnut-brown soil was the minimum. Harmful elements As, Cd, Hg, F and Pb in anthropogenic-alluvial soil of Hetao irrigation area showed enrichment characteristics in earth surface, with zonality vertically. Trace elements Cu and Zn, and beneficial elements P, K20, CaO, MgO and Se showed depletion. In anthropogenic-aUuvial soil of Ulansuhai of the Yellow River, harmful elements As and Cd showed significant enrichment in root system soil, while other elements showed depletion or was close to background value. In soil of plow pan, both beneficial component and harmful component showed enrichment characteristics. [Conclusion] Hetao irrigation area has the ideal geochemical conditions and heavy metal elements in muskmelon area meet the national standards.展开更多
In Ethiopia soil conservation is primarily meant to improve agriculture production.Therefore,assessment of the existing erosion hazards and classifying the land according to its capability are essential.This paper dep...In Ethiopia soil conservation is primarily meant to improve agriculture production.Therefore,assessment of the existing erosion hazards and classifying the land according to its capability are essential.This paper depicts the land degradation status and causes,through an integrated assessment,and some measures to alleviate the problem are proposed.展开更多
[Objective] This study aimed to investigate the impact of vanadium at dif- ferent concentration on enzyme activity and microbial biomass in soils. [Method] Us- ing pot experiments in the growth cabinet, we would like ...[Objective] This study aimed to investigate the impact of vanadium at dif- ferent concentration on enzyme activity and microbial biomass in soils. [Method] Us- ing pot experiments in the growth cabinet, we would like to investigate the changes of the soil enzyme activity and microbial biomass at different growing stages of rape (Brassica juncea L.) at different soil vanadium concentrations (soil background value was 147 mg/kg, spiked with 0, 50, 100, 150, 250 and 500 mg/kg of exogenous vanadium). [Result] Among all enzymes examined, polyphenol oxidase was most sensitive to soil vanadium. Addition of 50 mg/kg vanadium decreased its activity up to 56% of the control probably due to the vanadium toxicity. In comparison, the ac- tivities of sucrase, urease and catalase was less affected by soil vanadium. Surpris- ingly, the activity of sucrase, urease and catalase at the rape seedling stage differed significantly from at the maturity stage, highlighting the potential impact of plant growth on the vanadium-soil enzyme interaction. Different soil vanadium concentra- tions led to increases of microbial biomass to different extents. However, the corre- lation between soil microbial biomass carbon and phosphorus with vanadium con- centrations was insignificant. This revealed that the presence of additional factors (eg. plant) affected soil microbial biomass carbon and phosphorus aside from soil vanadium. [Conclusion] Polyphenol oxidase may be considered as an indicator of soil vanadium contamination. Due to the highly complicated interaction between vanadium and soil biological activities during plant growth, more investigations are required to reveal the mechanisms beyond our findings here.展开更多
Objective] The research aimed to study soil organic carbon and total ni-trogen distribution in oasis cotton farmland. [Method] With the oasis cotton field of Manas River Val ey in Tianshan Mountains as the research ar...Objective] The research aimed to study soil organic carbon and total ni-trogen distribution in oasis cotton farmland. [Method] With the oasis cotton field of Manas River Val ey in Tianshan Mountains as the research area and abandoned farmland as a control, the distribution characteristics of soil organic carbon and total nitrogen content in the cotton field of Manas River Val ey in the last 23 years were investigated by using geographic methods. [Result] Presenting vertical distribution, cotton soil organic carbon and total nitrogen content in Manas River Val ey de-creased with the increase of soil depth, and those in 0-30 cm soil layer was sig-nificantly higher than those in soil layer of below 30 cm, while organic carbon stor-age showed the trend of increase. Also in vertical distribution, soil organic carbon and total nitrogen decreased significantly with the increase of soil depth, and soil organic carbon content in abandoned farmland decreased month by month. Howev-er, cotton soil organic carbon storage firstly decreased and then increased in the oasis cotton field that in the early growth of cotton, soil organic carbon in the layers of 0-30 and 30-100 cm decreased to the lowest in the bloom stage, and then or-ganic carbon increased with the reproductive growth of cotton into the later stages. However, due to no input of plant litter in the abandoned farmland, the soil organic carbon storage decreased month by month. There were significantly differences be-tween oasis cotton field and abandoned farmland in organic carbon contents. [Con-clusion] The soil organic carbon content and total nitrogen content in oasis cotton field were significantly higher than those in the abandoned farmland. The soil organ-ic carbon storage increased in the layer of 0-30 cm, while there was no significant change of soil organic carbon and total nitrogen content in the layer of 30-100 cm, which was consistent with the previous study on the distribution characteristics of soil organic carbon and total nitrogen content profile.展开更多
Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thic...Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thickness of covering soil and medium of covering soil to establish a self-regulating ecosystem, the thickness of covering soil of land reclamation for plants in different living forms by synusia structure of plant below-ground habitat and medium of covering soil by ecological factors of plant below-ground habitat were studied. Synusia structure of plant below-ground habitat was recognized through investigation on structure and root of plant community, and ecological factors were determined through soil profile investigation. The thickness and medium of covering soil of land reclamation for the tree, the shrub and the herb were proposed.展开更多
The soil hardness, soil water content and soil bulk density along the trails of six scenic spots in the Zhangjiajie World Geopark were measured and analyzed, and the integrated effects of tourism trampling on soils we...The soil hardness, soil water content and soil bulk density along the trails of six scenic spots in the Zhangjiajie World Geopark were measured and analyzed, and the integrated effects of tourism trampling on soils were evaluated for each scenic spots by calculating its soil impact indexes (SII) in the park. The results indicated that visitors' activities caused a serious influence on the soil in the park, especially in the two most used scenic spots-- Yellowstone Village and Gold Whip Stream. The impact of tourism on soil mainly occurred within 3 m along the trails. The impact shapes are classified into six type as single-sided node type, double-sided node type, cross node type, single-sided linkage type, double-sided linkage type and short-cut linkage type. Of six types of impact shapes, the single-sided node type and double-sided type were dominant. The average water contents of soil for six scenic spots at sample areas of 1 m, 2 m and 3 m from trial is 36.6%, 24.5% and 2.2% lower than that of the control area, respectively. The average soil hardness for six scenic spots at 1m, 2 m, and 3m from the trails tramped increased 167.9%, and 122.2%, and 15.8%, respectively, compared with the control area. Soil bulk density increased 26.5% at 1 m and 20.9% at 2 m from the trails. The main countermeasures for reducing the range and extent of tourism impact on soil are discussed.展开更多
As the first event of soil erosion, rain splash erosion supplies materials for subsequent transportation and en-trainment. The Loess Plateau, the southern hilly region and the Northeast China are subject to serious so...As the first event of soil erosion, rain splash erosion supplies materials for subsequent transportation and en-trainment. The Loess Plateau, the southern hilly region and the Northeast China are subject to serious soil and water loss; however, the characteristics of rain splash erosion in those regions are still unclear. The objectives of the study are to ana-lyze the characteristics of splash erosion on loess soil, red soil, purple soil and black soil, and to discuss the relationship between splash erosion and soil properties. Soil samples spatially distributed in the abovementioned regions were col-lected and underwent simulated rainfalls at a high intensity of 1.2mm/min, lasting for 5, 10, 15, and 20min, respectively. Rain splash and soil crust development were analyzed. It shows that black soil sample from Heilongjiang Province corre-sponds to the minimum splash erosion amount because it has high aggregate content, aggregate stability and organic mat-ter content. Loess soil sample from Inner Mongolia corresponds to the maximum splash erosion amount because it has high content of sand particles. Loess soil sample from Shanxi Province has relatively lower splash erosion amount be-cause it has high silt particle content and low aggregate stability easily to be disrupted under rainfalls with high intensity. Although aggregate contents of red soil and purple soil samples from Hubei and Guangdong provinces are high, the sta-bility is weak and prone to be disrupted, so the splash erosion amount is medium. Splash rate which fluctuates over time is observed because soil crust development follows a cycling processes of formation and disruption. In addition, there are two locations of soil crust development, one appears at the surface, and the other occurs at the subsurface.展开更多
Soil and land degradation in the tropics can be identified and described interms of physical, chemical, and biological changes from its pristine state brought about by naturaland anthropogenic influences. A characteri...Soil and land degradation in the tropics can be identified and described interms of physical, chemical, and biological changes from its pristine state brought about by naturaland anthropogenic influences. A characteristic of these ecosystems is their capacity to recyclenutrients through soil organic matter (SOM). Following disturbance through changed land management,SOM is rapidly mineralized and there is a corresponding decline in fertility and the variable chargecomponent of the cation exchange capacity. As these ecosystems are strongly dependent on SOM fortheir functionality, changed land use can have irreversible impacts on the productivity of thesesystems. The paper focuses on quantifying chemical degradation through 'benchmarking' using datafrom paired sites in tropical China and Thailand using surface charge fingerprinting. Using valuestaken from the fingerprint of an undisturbed soil, an index of chemical degradation from 'ideality'was calculated. Various management strategies that attempt to reverse degradative trends or improvepoor quality soils in their natural condition are discussed, such as the addition of natural claysand silicated materials. Results are present to show the effect of each of the aforementionedstrategies on surface charge characteristics and associated increases in plant productivity.展开更多
Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore...Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures.展开更多
The distribution of various fractions of Zn, Fe, Cu and Mn in 15 types of sods in China and its rela-tionship with plant availability were studied. Wactions of various elements were found to have some similarcharacter...The distribution of various fractions of Zn, Fe, Cu and Mn in 15 types of sods in China and its rela-tionship with plant availability were studied. Wactions of various elements were found to have some similarcharacteristic distribution regularities in wirious types of soils, but various soil types derered to varyingdegrees in the distribution of each fraction. Soil physico-chemical properties, such as pH, CEC and thecontents of OM, CaCO_3, free Fe, free Mn and P_2O_5, were signdicantly correlated with the distribution ofelemental fractions, and a significazit correlation also existed between the distribution and plant amilabilityof elemental fractions. Varfous fractions of each element were divided into two groups bed on their plantavailability. The correlation between the distribution of combination fractions aiid plaxit availability indi-cated a significantly or an extremely significantly positive correlation for Group I but a significantly or anextremely significantly negative correlation for Group II. Therefore, the fractions in Group I were primarypools of available nutrients, while those in Group II could hardly provide available nutrients for plants. Descreasing the transformation of corresponding elements into fractions of Group 11 and increasing the storagecapacity of various fractions of Group I were an important direction for regulation and controiling of soilnutrients. However, some Particular soils with too high contents of Zn, Fe, Cu and Mn should be regulatedand controlled adversely展开更多
The waste dump of open-pit coal mine is remade of soil-rock mixture under the action of gravity,dynamic load of transportation equipment and earthquake,etc.By using artificial synthetic transparent soil,the developing...The waste dump of open-pit coal mine is remade of soil-rock mixture under the action of gravity,dynamic load of transportation equipment and earthquake,etc.By using artificial synthetic transparent soil,the developing process and migration law for soil-rock mixture are observed in the remade process.The mixture of fused quartz sand,liquid paraffin and n-tridecane is chosen as the material for synthetic transparent soil which is mixed with liquid paraffin and n-tridecane at a mass ratio of4.4at room temperature of17℃.Physical and mechanical properties of transparent soil are determined by physical test and compared with those in natural sandy soil.The results show that transparent soil and sandy soil have high similarity,in other words,transparent soil can be used for similar simulation experiments of soil-rock mixture.展开更多
Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO T...Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system (Tlf) is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.展开更多
基金supported by National Natural Science Foundation of China (No 30872068)the Science and Technology Key Scientific Project of Heilongjiang Province (GA06B302-3)Fund of Thesis for Post Graduated Student of NEFU(GRAM09)
文摘A study was conducted to determine the characters of soil structure in different water and soil conservation forests in Keshan County,northwest of Heilongjiang Province,China.The soil bulk density,the ratio of non-capillary porosity and capillary porosity(NCP/CP),and the generalized soil structure index(GSSI) were measured for Fraxinus mandshurica,Larix gmelini,Pinus sylvestris var.mongolica,and Picea koraiensis plantations as well as the abandoned land(as control) adjacent to the forests in typical black soil region.Results show that at soil depth of 0–30cm,the soil bulk density of F.mandshurica forest and L.gmelini forest was lower than that of P.sylvestris var.mongolica forest and P.koraiensis forest,with the relative decrease of 8.04%–11.01%.The soil bulk density of L.gmelini forest was significantly different from that of the P.sylvestris var.mongolica forest and P.koraiensis forest.The NCP/CP values of the four types of plantations were all higher(59.75%–128.82% relatively) than that of abandoned land(p〈0.05),indicating that the soil aeration and permeability under forest were enhanced,especially under L.gmelini forest.GSSI values of the four types of forests were also relatively higher(2.98%–4.36%) than abandoned land(p〈0.05),indicating that those soil and water conservation forests,especially the F.mandshurica forest and P.koraiensis forest,can promote soil condition to approximate ideal soil structure.The result of this study can provide theoretical basis for scientifically evaluating the effects of vegetation restoration on soil quality in typical black soil region.
基金Supported by the Foundation of Key Laboratory of Resources RemoteSensing and Digital Agriculture of Chinese Ministry of Agriculture(RDA091 0)Commonweal Foundation of China's National Academy(200990124)+2 种基金Major Program of National Natural ScienceFoundation of China(409301 01)National Key Technologies R& D Program of China(2006BAC08B0404)National Science andTechnology Project of China(2007BAC03A10)~~
文摘In order to provide some preliminary recommendations for the sustainable use and management of croplands, land suitability evaluation for crops was carried out in Shouyang County which partly locates on the Loess Plateau suffering severe soil and water erosion and is characterized by ecological vulnerability and semi-arid climate. Here, land suitability for 4 local crops of maize, wheat, sorghum and millet under 2 cultivation senarios of tradition and mechanization was evaluated by a upscaling approach. The upscaling was implemented in a land form hierarchy which was composed of land unit, land facet and land site at 3 spatial levels. The IAO land suitability evaluation model for crops was revised by applying a meteorological revision index. Rresults showed that a polarized phenomenon occurred, which means that the most suitable class (S1) and the most unsuitable class (N2) were predominant in acreage percentage for all the 4 crops. Maize, millet and wheat were relatively more adaptive to be grown and should be ploughed in the traditional mode. Hence, future cropland use policy should pay more attention to the conversion of arable land to forestland and grassland in unsuitable areas and to more investment for agricultural production in suitable regions, and it is necessary to balance the relationship between the livelihood of local farmers and environmental protection to maintain a healthy and stable ecosystem.
基金Supported by The National Project of Science & Technique Achievement Transformation(2008GB2B200089)Heilongjiang Nongken Zongju Science & Technological Key Project(HNKXI-01-06-01)Heilongjiang Nongken Zongju Science & Technological Development Project(NKKF06-10-1)~~
文摘[Objective] The research aimed to explore how to use the soil reasonably,prevent the degradation of soil fertility,maintain soil fertility,improve the ecological environment of paddy field and improve the soil productivity of paddy field from the cultivation aspect.[Method] Taking kenjiandao 10 as the material,the variation laws of root weight,soil physical and chemical characteristics,soil enzyme,straw decomposition rate,soil temperature,microorganism of rice under the planting patterns of water-saving pro...
基金Supported by the Special Fund for Agro-scientific Research in the Public Interest of China(201203030,201203050)Special Fund for "Taishan Scholar" Construction Engineering "Agricultural Nonpoint Source Pollution Prevention and Control"~~
文摘[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experiment in Jinan of Shandong Province was selected and the results of soil nutrient and crop yield in 1984, 1987, 1988, 1989, 1990, 2001, 2005, 2006, 2007 and 2010 were measured and collected. In this study, five treatments: CK, NP, NK, PK and NPK of the located experiment were selected. [Result] The three types of soils in wheat yields decreased signifi- cantly in the first several years and in 2006. Wheat yields of the treatments with P fertilizers were obviously higher than those without P fertilizers; it was shown that phosphorus is the primary nutritional factor for high-yielding of wheat. The highest yield is from cinnamon soil, followed by that from brown soil, and the lowest pro- duction is from fluvo-aquic soil. Under the same fertilization, the influence of other factors on wheat yield of brown soil is the smallest, while cinnamon soil is vulnera- ble to the influence of external conditions, resulting in larger fluctuation of annual wheat yield. The alkali-hydro nitrogen contents of three kinds of soils first de- creased, then raised, and at last reduced apparently. Since 2007, the change of al- kali-hydro nitrogen content appeared rebounded. The available P contents of no- phosphorus treatments decreased over time while those of the treatments with P fertilizers increased at first, then decreased, and after that kept relatively stable. The available K contents of no K treatments decreased slowly. The treatments of PK and NK had higher available K content than NPK treatment. [Conclusion] Thus, it is an effective fertilization measure to improve the wheat yield by supplying reasonable phosphate fertilizer and nitrogen fertilizer and making up potassium fertilizer.
基金Supported by Science&Technology Support for Xinjiang(201191143)Special Fund for Xinjiang Water Conservancy Science&Technology(2013T04,2013T05)Key Laboratory of Construction Project of Xinjiang Academy of Agricultural Sciences(xjnkkl-2013-001)~~
文摘The aim was to analyze effects of jujube planting years on changes of soil nutrient elements and explore the causes of orchard degradation by researching variation characteristics of soil nutrient contents in orchards with different planting years, providing theoretical support for the soil degradation of jujube or-chards. [Method] Soil samples were col ected in depth at 0-20 and 20-40 cm from the sites in or out of tree canopy scope in jujube orchards with 3, 5 and 7 plan-ning-years, to analyze contents of available N, P and K, organic matter, total N, salts, and trace elements, as wel as changes of nutritional elements. [Result] Avail-able boron, copper, iron, manganese, zinc and available potassium in soils of jujube orchards with 3, 5 and 7 years planting history reduced as planting year increased, which coincided with that in the soil of 20-40 cm. [Conclusion] Because trace ele-ments are never applied in southern Xinjiang, available B, Cu, Fe, Mn, and Zn and available K would be consumed by tree root growth. Due to root distribution differ-ences and ploughing effects in fields, the contents of nutrients tend to be volatile in or out of tree canopy scope. Tree root in deeper soils absorbs more nutrients, and soil nutrients would decrease dramatical y if additional chemical fertilizers are not provided, leading to soil degradation.
基金supported by the Knowledge Inno-vation Project of the Chinese Academy of Sciences (KZCX2-YW-416)the National Natural Science Foundation (90411020)
文摘A stdudy was conducted to determine the seasonal changes of soil respiration and the contribution of root respiration to soil respiration in Betula plaophylla forest in Changbai Mountain from May to September in 2004. Results indicated that the total soil respiration, root-severed soil respiration and the root respiration followed a similar seasonal trend, with a high rate in summer due to wet and high temperature and a low rate in spring and autumn due to lower temperature. The mean rates of total soil respiration, root-severed soil respiration and root respiration were 4.44, 2.30 and 2.14 μmol.m^-2.s^-1, respectively during the growing season, and they were all exponentially correlated with temperature. Soil respiration rate had a linear correlation with soil volumetric moisture. The Q10 values for total soil respiration, root-severed soil respiration and root respiration were 2,82, 2.59 and 3. 16, respectively. The contribution rate of root respiration to the total soil respiration was between 29.3% and 58.7% during the growing season, indicating that root is a major component of soil respiration. The annual mean rates of total soil respiration, root-severed soil respiration and root respiration were 1.96, 1.08, and 0.87 μmol.m^-2.s^-1, or 741.73 408.71, and 329.24 g.m^-2.a^-1, respectively. Root respiration contributed 44.4% to the annual total soil respiration. The relationship proposed for soil respiration with soil lemperature was useful for understanding and predicting potential changes in Changbai Mountain B. platyphylla forest ecosystem in response to forest management and climate change.
基金This research was supported by National Natural Science Foundation of China (40173033) and Important Direction Project of Knowl-edge Innovation of Chinese Academy of Sciences (KZCX3-SW-423).
文摘In August 2003, we investigated spatial pattern in soil carbon and nutrients in the Alpine tundra of Changbai Moun-tain, Jilin Province, China. The analytical results showed that the soil C concentrations at different depths were significantly (p<0.05) higher in Meadow alpine tundra vegetation than that in other vegetation types; the soil C (including inorganic carbon) concentrations at layer below 10 cm are significantly (p<0.05) higher than at layer of 1020 cm among the different vegetation types; the spatial distribution of soil N concentration at top surface of 0-10 cm depth was similar to that at 1020 cm; the soil P concentrations at different depths were significantly (p<0.05) lower at Lithic alpine tundra vegetation than that at other vegetation types; soil K concentration was significantly (p<0.05) higher in Felsenmeer alpine tundra vegetation and Lithic alpine tundra vegetation than that in Typical alpine tundra, Meadow alpine tundra, and Swamp alpine tundra vegetations.. However, the soil K had not significant change at different soil depths of each vegetation type. Soil S concentration was dramatically higher in Meadow alpine tundra vegetation than that in other vegetation types. For each vegetation type, the ratios of C: N, C: P, C: K and C: S generally decreased with soil depth. The ratio of C: N was significantly higher at 010 cm than that at 1020 cm for all vegetation types except at the top layer of the Swamp alpine tundra vegetation. Our study showed that soil C and nutrients storage were significantly spatial heterogeneity.
基金Supported by National Land and Resources Investigation Program(200414200005)~~
文摘[Objective] The aim was to evaluate the eco-geochemical characteristics and geochemistry conditions of root soil in muskmelon planting area, evaluate the soil environment quality in Hetao irrigation area and provide scientific basis for the musmelon planting in this area. [Method] Root system soil sample and plow pan sample were collected from the main muskmelon planting area in Hetao irrigation area, so as to analyze the contents of heavy metal elements. By comparing with the Soft Environmental Quality Standard (GB15618-1995), the research explored whether the heavy metal elements in root system met the national standard. [Result] Heavy metal elements in root system soil had the maximum content in recession area of Yellow River, followed by saline soils. The content of heavy metal elements in chestnut-brown soil was the minimum. Harmful elements As, Cd, Hg, F and Pb in anthropogenic-alluvial soil of Hetao irrigation area showed enrichment characteristics in earth surface, with zonality vertically. Trace elements Cu and Zn, and beneficial elements P, K20, CaO, MgO and Se showed depletion. In anthropogenic-aUuvial soil of Ulansuhai of the Yellow River, harmful elements As and Cd showed significant enrichment in root system soil, while other elements showed depletion or was close to background value. In soil of plow pan, both beneficial component and harmful component showed enrichment characteristics. [Conclusion] Hetao irrigation area has the ideal geochemical conditions and heavy metal elements in muskmelon area meet the national standards.
文摘In Ethiopia soil conservation is primarily meant to improve agriculture production.Therefore,assessment of the existing erosion hazards and classifying the land according to its capability are essential.This paper depicts the land degradation status and causes,through an integrated assessment,and some measures to alleviate the problem are proposed.
基金Supported by the National Natural Science Foundation of China(41101484)Swiss National Science Foundation PZ00P2(142232)~~
文摘[Objective] This study aimed to investigate the impact of vanadium at dif- ferent concentration on enzyme activity and microbial biomass in soils. [Method] Us- ing pot experiments in the growth cabinet, we would like to investigate the changes of the soil enzyme activity and microbial biomass at different growing stages of rape (Brassica juncea L.) at different soil vanadium concentrations (soil background value was 147 mg/kg, spiked with 0, 50, 100, 150, 250 and 500 mg/kg of exogenous vanadium). [Result] Among all enzymes examined, polyphenol oxidase was most sensitive to soil vanadium. Addition of 50 mg/kg vanadium decreased its activity up to 56% of the control probably due to the vanadium toxicity. In comparison, the ac- tivities of sucrase, urease and catalase was less affected by soil vanadium. Surpris- ingly, the activity of sucrase, urease and catalase at the rape seedling stage differed significantly from at the maturity stage, highlighting the potential impact of plant growth on the vanadium-soil enzyme interaction. Different soil vanadium concentra- tions led to increases of microbial biomass to different extents. However, the corre- lation between soil microbial biomass carbon and phosphorus with vanadium con- centrations was insignificant. This revealed that the presence of additional factors (eg. plant) affected soil microbial biomass carbon and phosphorus aside from soil vanadium. [Conclusion] Polyphenol oxidase may be considered as an indicator of soil vanadium contamination. Due to the highly complicated interaction between vanadium and soil biological activities during plant growth, more investigations are required to reveal the mechanisms beyond our findings here.
基金Supported by the National Natural Science Foundation of China(31360320)~~
文摘Objective] The research aimed to study soil organic carbon and total ni-trogen distribution in oasis cotton farmland. [Method] With the oasis cotton field of Manas River Val ey in Tianshan Mountains as the research area and abandoned farmland as a control, the distribution characteristics of soil organic carbon and total nitrogen content in the cotton field of Manas River Val ey in the last 23 years were investigated by using geographic methods. [Result] Presenting vertical distribution, cotton soil organic carbon and total nitrogen content in Manas River Val ey de-creased with the increase of soil depth, and those in 0-30 cm soil layer was sig-nificantly higher than those in soil layer of below 30 cm, while organic carbon stor-age showed the trend of increase. Also in vertical distribution, soil organic carbon and total nitrogen decreased significantly with the increase of soil depth, and soil organic carbon content in abandoned farmland decreased month by month. Howev-er, cotton soil organic carbon storage firstly decreased and then increased in the oasis cotton field that in the early growth of cotton, soil organic carbon in the layers of 0-30 and 30-100 cm decreased to the lowest in the bloom stage, and then or-ganic carbon increased with the reproductive growth of cotton into the later stages. However, due to no input of plant litter in the abandoned farmland, the soil organic carbon storage decreased month by month. There were significantly differences be-tween oasis cotton field and abandoned farmland in organic carbon contents. [Con-clusion] The soil organic carbon content and total nitrogen content in oasis cotton field were significantly higher than those in the abandoned farmland. The soil organ-ic carbon storage increased in the layer of 0-30 cm, while there was no significant change of soil organic carbon and total nitrogen content in the layer of 30-100 cm, which was consistent with the previous study on the distribution characteristics of soil organic carbon and total nitrogen content profile.
文摘Land reclamation is a process of ecosystem reconstruction, for which it is very important to keep co-adaptation between plants and the below ground habitat. In order to keep the co-adaptation among plant species, thickness of covering soil and medium of covering soil to establish a self-regulating ecosystem, the thickness of covering soil of land reclamation for plants in different living forms by synusia structure of plant below-ground habitat and medium of covering soil by ecological factors of plant below-ground habitat were studied. Synusia structure of plant below-ground habitat was recognized through investigation on structure and root of plant community, and ecological factors were determined through soil profile investigation. The thickness and medium of covering soil of land reclamation for the tree, the shrub and the herb were proposed.
基金This study was supported by the National Natural Science Foundation of China (NSFC30200040) and the Thousand-hundred-ten Talent Engineering project of Guangdong Province, P. R. China (03130401)
文摘The soil hardness, soil water content and soil bulk density along the trails of six scenic spots in the Zhangjiajie World Geopark were measured and analyzed, and the integrated effects of tourism trampling on soils were evaluated for each scenic spots by calculating its soil impact indexes (SII) in the park. The results indicated that visitors' activities caused a serious influence on the soil in the park, especially in the two most used scenic spots-- Yellowstone Village and Gold Whip Stream. The impact of tourism on soil mainly occurred within 3 m along the trails. The impact shapes are classified into six type as single-sided node type, double-sided node type, cross node type, single-sided linkage type, double-sided linkage type and short-cut linkage type. Of six types of impact shapes, the single-sided node type and double-sided type were dominant. The average water contents of soil for six scenic spots at sample areas of 1 m, 2 m and 3 m from trial is 36.6%, 24.5% and 2.2% lower than that of the control area, respectively. The average soil hardness for six scenic spots at 1m, 2 m, and 3m from the trails tramped increased 167.9%, and 122.2%, and 15.8%, respectively, compared with the control area. Soil bulk density increased 26.5% at 1 m and 20.9% at 2 m from the trails. The main countermeasures for reducing the range and extent of tourism impact on soil are discussed.
基金Under the auspices of National Natural Science Foundation of China ( No. 40471084)Innovation Program of Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (No. 066U0104SZ)State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau (No. 10501-173)
文摘As the first event of soil erosion, rain splash erosion supplies materials for subsequent transportation and en-trainment. The Loess Plateau, the southern hilly region and the Northeast China are subject to serious soil and water loss; however, the characteristics of rain splash erosion in those regions are still unclear. The objectives of the study are to ana-lyze the characteristics of splash erosion on loess soil, red soil, purple soil and black soil, and to discuss the relationship between splash erosion and soil properties. Soil samples spatially distributed in the abovementioned regions were col-lected and underwent simulated rainfalls at a high intensity of 1.2mm/min, lasting for 5, 10, 15, and 20min, respectively. Rain splash and soil crust development were analyzed. It shows that black soil sample from Heilongjiang Province corre-sponds to the minimum splash erosion amount because it has high aggregate content, aggregate stability and organic mat-ter content. Loess soil sample from Inner Mongolia corresponds to the maximum splash erosion amount because it has high content of sand particles. Loess soil sample from Shanxi Province has relatively lower splash erosion amount be-cause it has high silt particle content and low aggregate stability easily to be disrupted under rainfalls with high intensity. Although aggregate contents of red soil and purple soil samples from Hubei and Guangdong provinces are high, the sta-bility is weak and prone to be disrupted, so the splash erosion amount is medium. Splash rate which fluctuates over time is observed because soil crust development follows a cycling processes of formation and disruption. In addition, there are two locations of soil crust development, one appears at the surface, and the other occurs at the subsurface.
基金Project financially supported by the Australian Centre for International Agricultural Research(ACIAR) and the Sugar Research and Development Corporation(SRDC),Australia.
文摘Soil and land degradation in the tropics can be identified and described interms of physical, chemical, and biological changes from its pristine state brought about by naturaland anthropogenic influences. A characteristic of these ecosystems is their capacity to recyclenutrients through soil organic matter (SOM). Following disturbance through changed land management,SOM is rapidly mineralized and there is a corresponding decline in fertility and the variable chargecomponent of the cation exchange capacity. As these ecosystems are strongly dependent on SOM fortheir functionality, changed land use can have irreversible impacts on the productivity of thesesystems. The paper focuses on quantifying chemical degradation through 'benchmarking' using datafrom paired sites in tropical China and Thailand using surface charge fingerprinting. Using valuestaken from the fingerprint of an undisturbed soil, an index of chemical degradation from 'ideality'was calculated. Various management strategies that attempt to reverse degradative trends or improvepoor quality soils in their natural condition are discussed, such as the addition of natural claysand silicated materials. Results are present to show the effect of each of the aforementionedstrategies on surface charge characteristics and associated increases in plant productivity.
基金Supported by the National Basic Research Program of China(2007CB407204)~~
文摘Ridge tillage, which is a very common and important tillage measure in the black soil area of northeast China, has some soil and water conservation bene- fits, but has little attention. It is very important to explore the spatial distribution of the ridge direction of the arable land and its soil and water conservation benefits in different terrain conditions in the black soil area. So Binxian County of Heilongjiang Province was selected as the study area, and 168 field investigation units were ex- tracted by stratified sampling method and investigated. According to equations of slope gradient factor and slope gradient in ridge direction, and based on the soft- ware of Arcmap, SPSS and Excel, the investigation data of soil and water loss in Binxian County were analyzed and counted, The results show that in plain, hilly and mountainous areas, the average ground slope gradients are 1.92°, 6.20° and 8.27° respectively, and the average slope gradients along ridge direction are 1.33°, 4.52°and 6.45° respectively, which account for about 70%, 73% and 78% of the average ground slope gradients in the same terrain condition; the relative quantities of soil erosion in the present ridge tillage condition account for about 55%, 69% and 67% respectively of that in down-slope ridge tillage conditions, so the present ridge tillage has obviously relative soil and water conservation benefits. Based on these results, the reasons of the present ridge tillage status were analyzed, and some reform measures were proposed. The results could not only help to comprehend the spatial distribution and soil and water conservation benefits of ridge tillage in the black soil area of Northeast China, but also provide scientific references for the layout of local soil and water conservation measures.
文摘The distribution of various fractions of Zn, Fe, Cu and Mn in 15 types of sods in China and its rela-tionship with plant availability were studied. Wactions of various elements were found to have some similarcharacteristic distribution regularities in wirious types of soils, but various soil types derered to varyingdegrees in the distribution of each fraction. Soil physico-chemical properties, such as pH, CEC and thecontents of OM, CaCO_3, free Fe, free Mn and P_2O_5, were signdicantly correlated with the distribution ofelemental fractions, and a significazit correlation also existed between the distribution and plant amilabilityof elemental fractions. Varfous fractions of each element were divided into two groups bed on their plantavailability. The correlation between the distribution of combination fractions aiid plaxit availability indi-cated a significantly or an extremely significantly positive correlation for Group I but a significantly or anextremely significantly negative correlation for Group II. Therefore, the fractions in Group I were primarypools of available nutrients, while those in Group II could hardly provide available nutrients for plants. Descreasing the transformation of corresponding elements into fractions of Group 11 and increasing the storagecapacity of various fractions of Group I were an important direction for regulation and controiling of soilnutrients. However, some Particular soils with too high contents of Zn, Fe, Cu and Mn should be regulatedand controlled adversely
基金Project(2015QNA40)supported by the Fundamental Research Funds for the Central Universities,China
文摘The waste dump of open-pit coal mine is remade of soil-rock mixture under the action of gravity,dynamic load of transportation equipment and earthquake,etc.By using artificial synthetic transparent soil,the developing process and migration law for soil-rock mixture are observed in the remade process.The mixture of fused quartz sand,liquid paraffin and n-tridecane is chosen as the material for synthetic transparent soil which is mixed with liquid paraffin and n-tridecane at a mass ratio of4.4at room temperature of17℃.Physical and mechanical properties of transparent soil are determined by physical test and compared with those in natural sandy soil.The results show that transparent soil and sandy soil have high similarity,in other words,transparent soil can be used for similar simulation experiments of soil-rock mixture.
基金supported by the CAS West-Developing Initiative (Grant No. KZCX2-XB2-07)the Key Technologies R & D Program of China (Grant No. 2008BAD98B04)
文摘Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system (Tlf) is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.