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An artificial neural network (ANN)-based approach for predicting deflection of diaphragm walls caused by braced excavation in soft to medium clays is presented in this study. Five enter variables including excavation depth system stiffness excavation width shear strength normalized with vertical effective stress and Young’s modulus normalized with vertical effective stress are adopted as inputs to the ANN. The database for training and testing the ANN is generated from hypothetical cases using finite element method. The performance of the developed ANN reveals that the influence of each input variable on the wall deflection is consistent with the excavation behaviors generally observed in the field. The validation using 12 excavation case histories collected in this study shows that the wall deflection caused by braced excavation can be accurately predicted by the developed ANN. This study presents a nonlinear optimization technique (NOT) for conducting the back analyses of geotechnical engineering problems based on the handle observations. Additional auxiliary techniques are incorporated to compound the convergence and stability of the NOT. The developed NOT and additional auxiliary techniques are incorporated into a finite element code and then applied to the back analysis of excavation-induced wall deflection. A number of hypothetical excavation cases with various scenarios of stratigraphy and two quality excavation inspect histories are used to validate the developed NOT in which the dominant soil parameters are treated as target parameters. Results show that the wall deflections of all hypothetical and actual excavation cases at each stage can be accurately and efficiently back-figured. The developed NOT has a potential to be an useful tool for preventing the building damage through accurately and efficiently predicting the excavation-induced deformations at subsequent stages. The selection of retaining walls supporting deep excavations for building basements on various factors such as soil types permissible movements construction methods material and equipment availability etc. For excavations in soft soils rigid walls such as diaphragm walls and contiguous bored pile walls are commonly used as they are more effective than the more flexible walls such as sheet pile walls in limiting soil movements to an acceptable level. For excavations in stiff soils the relative merits for the rigid and flexible walls become less clear. This paper compares the performance and cost-effectiveness of rigid and flexible walls. The relative merits between the rigid and flexible wall systems are discussed. We examine the small-strain behavior of Taipei clays in braced excavation through a detailed analysis of a well-documented case history. Specifically we care for the case of the Taipei National Enterprise Center (TNEC) excavation using two soil models the Modified Cam-clay copy (MCC) and the three-Surface Kinematic Hardening model (3-SKH). Our finite element analysis includes a consideration of the over-consolidated stress state and the high sign shear modulus of the clay. Results show that the observed wall deflection and surface settlement can be satisfactorily predicted simultaneously using the 3-SKH model. This is an improvement on the MCC model for which only wall deflection not ground settlement can be accurately predicted. This study re-confirms the importance of considering small-strain non-linear behavior for the over-consolidated stress state in finite element analyses of braced excavation responses. In this study a neural network algorithm has been used to model the soil-structure interaction behavior of deep excavations in clays. The hybrid evolutionary Bayesian back-propagation (EBBP) neural network was used in this study and utilizes the genetic algorithms and gradient descent method to determine the optimal parameters within a Bayesian framework to regularize the complexity of learning and to statistically reflect the uncertainty in data. The EBBP analysis was carried out on an extensive database of braced excavation performance from finite element analyses. Additional parametric studies indicate that the model gives logical and consistent trends. Back-analyses of some instrumented case histories from the literature also indicate that the trained neural network model gives reasonable predictions in comparison to the actual measured values. The trained model can serve as a simple and reliable prediction tool to enable estimates of maximum wall deflection for preliminary design of braced excavations in clay. The model is able to take into consideration various factors such as the wall stiffness support stiffness the in-situ stress state non-homogeneous soil conditions and the variation of soil properties with depth. An added advantage of this approach is that it provides meaningful error bars for the model predictions. Excessive wall deflection and ground settlement are common problems for deep excavations in soft clay and frequently damage adjacent buildings. To reduce wall deflection or ground settlement the in situ alter is usually strengthened by jet grouting or mechanical deep mixing method. Finite element analysis can be conducted to determine improvement ratios improved depths and improved zones of the soil to reach a balance between cost and safety. However the conventional two dimensional finite element method does not take into account corner effects which will affect the determination of improved zones. A three-dimensional finite element method is thus appropriate for analysis. In this study an excavation 51.65 m long. 23.75 wide and 9.31 m deep was used as an example to show how to design the improved zone using ideas of corner effects and the three-dimensional finite element method. It was open from a series of parametric studies that the lateral wall deflection was virtually not affected if the area within 8 m from the corners was or was not improved which was subsequently used for the ground improvement in the actual excavation. The wall deflections were carefully observed during excavation. It was found that the measured wall deflections were change state to those originally designed. The adjacent buildings near the excavation site were thus protected.

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An artificial neural network (ANN)-based come for predicting deflection of diaphragm walls caused by braced excavation in soft to medium clays is presented in this study. Five input variables including excavation depth system stiffness excavation width shear strength normalized with vertical effective evince and Young’s modulus normalized with vertical effective stress are adopted as inputs to the ANN. The database for training and testing the ANN is generated from hypothetical cases using finite element method. The performance of the developed ANN reveals that the influence of each input variable on the wall deflection is consistent with the excavation behaviors generally observed in the field. The validation using 12 excavation inspect histories collected in this study shows that the wall deflection caused by braced excavation can be accurately predicted by the developed ANN. This study presents a nonlinear optimization technique (NOT) for conducting the approve analyses of geotechnical engineering problems based on the field observations. Additional auxiliary techniques are incorporated to enhance the convergence and stability of the NOT. The developed NOT and additional auxiliary techniques are incorporated into a finite element code and then applied to the back analysis of excavation-induced wall deflection. A number of hypothetical excavation cases with various scenarios of stratigraphy and two quality excavation case histories are used to validate the developed NOT in which the dominant alter parameters are treated as target parameters. Results show that the wall deflections of all hypothetical and actual excavation cases at each stage can be accurately and efficiently back-figured. The developed NOT has a potential to be an useful tool for preventing the building damage through accurately and efficiently predicting the excavation-induced deformations at subsequent stages. The selection of retaining walls supporting deep excavations for building basements on various factors such as soil types permissible movements construction methods material and equipment availability etc. For excavations in soft soils rigid walls such as diaphragm walls and contiguous bored pile walls are commonly used as they are more effective than the more flexible walls such as sheet pile walls in limiting soil movements to an acceptable level. For excavations in stiff soils the relative merits for the rigid and flexible walls become less clear. This paper compares the performance and cost-effectiveness of rigid and flexible walls. The relative merits between the rigid and flexible wall systems are discussed. We examine the small-strain behavior of Taipei clays in braced excavation through a detailed analysis of a well-documented case history. Specifically we analyze the case of the Taipei National Enterprise Center (TNEC) excavation using two soil models the Modified Cam-clay model (MCC) and the three-Surface Kinematic Hardening model (3-SKH). Our finite element analysis includes a consideration of the over-consolidated stress state and the high initial clip modulus of the clay. Results show that the observed wall deflection and surface settlement can be satisfactorily predicted simultaneously using the 3-SKH model. This is an improvement on the MCC model for which only wall deflection not fasten settlement can be accurately predicted. This study re-confirms the importance of considering small-strain non-linear behavior for the over-consolidated evince state in finite element analyses of braced excavation responses. In this study a neural network algorithm has been used to model the soil-structure interaction behavior of deep excavations in clays. The hybrid evolutionary Bayesian back-propagation (EBBP) neural network was used in this study and utilizes the genetic algorithms and gradient descent method to determine the optimal parameters within a Bayesian framework to regularize the complexity of learning and to statistically reflect the uncertainty in data. The EBBP analysis was carried out on an extensive database of braced excavation performance from finite element analyses. Additional parametric studies indicate that the model gives logical and consistent trends. Back-analyses of some instrumented case histories from the literature also indicate that the trained neural network copy gives reasonable predictions in comparison to the actual measured values. The trained model can answer as a simple and reliable prediction tool to enable estimates of maximum wall deflection for preliminary design of braced excavations in clay. The model is able to take into consideration various factors such as the wall stiffness support stiffness the in-situ stress state non-homogeneous soil conditions and the variation of soil properties with depth. An added advantage of this come is that it provides meaningful error bars for the model predictions. Excessive wall deflection and ground settlement are common problems for deep excavations in soft clay and frequently damage adjacent buildings. To reduce wall deflection or ground settlement the in situ soil is usually strengthened by jet grouting or mechanical deep mixing method. Finite element analysis can be conducted to determine improvement ratios improved depths and improved zones of the soil to reach a balance between cost and safety. However the conventional two dimensional finite element method does not take into account corner effects which will alter the determination of improved zones. A three-dimensional finite element method is thus appropriate for analysis. In this study an excavation 51.65 m long. 23.75 wide and 9.31 m deep was used as an example to show how to design the improved zone using ideas of corner effects and the three-dimensional finite element method. It was found from a series of parametric studies that the lateral wall deflection was virtually not affected if the area within 8 m from the corners was or was not improved which was subsequently used for the ground improvement in the actual excavation. The wall deflections were carefully observed during excavation. It was found that the measured wall deflections were close to those originally designed. The adjacent buildings near the excavation site were thus protected.

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In the Loess Plateau soil desiccation has become a serious problem for forest and grass vegetation. alter desiccation leads to the formation of a dried soil layer (DSL). This paper presents the results of research carried out in the central move of the Loess Plateau. The objective of the research was to produce a statistically supported set of indicators for evaluating soil desiccation of forestlands to show a heuristic idea for alter desiccation and to supply scientific give for replacing farmland with plant or grass in the Loess Plateau and other regions of China. Here we suggest that more attention should be paid to soil desiccation and its effects on the ecosystem of the region in the future. The results showed that natural Quercus liaotungensis forestlands (NQF) retained more water circumscribe than regrown Robinnia pseudoscacia forestlands (RRF). Significant DSLs were formed in the RRF but not in the NQF. A possible reason for no formation of DSL in NQF could be due to the presence of an arbor–shrub–herb stand structure and large humus and litter accumulation which increased the natural plant's (NF) adaptability to the environmental conditions. Soil wet content in the north-facing angle was significantly larger than in the south-facing slope. DSLs formed in the 0–500 cm forge of the south-facing angle. When slope gradient was greater than 25° alter wet content deceased sharply and showed significant difference compared with 9°. 15° and 20° (P < 0.05). So we conclude that plant species aspect and slope angle could be the predicators for the formation of DSLs. The analysis on alter physical properties of 0–60 cm layer indicated that plant species aspect and slope angle also have significant effects on bulge density porosity plant-available capacity and hydraulic conductivity especially in the 0–20 and 20–40 cm layers. In the NQF and RRF with north-facing slope soil physical properties were improved. Severe soil and wet loss has lead to widespread arrive degradation in China's loess plateau. During the past decades a great broach of effort was made on vegetation restoration to decrease alter and wet loss in the loess plateau. However due to wet shortage the efficiency of vegetation restoration was not as satisfactory as expected. As part of a vegetation restoration project we conducted research aiming to understand the relationship between vegetation pattern and soil water dynamics. The goal was to find vegetation types appropriate for the loess plateau with scarce wet resources. In 1986 fifteen plots of arrive were planted with five vegetation types: hanker woodland shrubland sloping cropland alfalfa and semi-natural grassland. Soil water circumscribe runoff soil erosion were measured for each plot. Environmental variables such as rainfall evaporation and temperature were recorded simultaneously by an automated meteorological displace. The relationship between land cover pattern and soil wet dynamic was evaluated by using statistical models. We found that: (1) alter wet loss occurred during the growing toughen and it reached the maximum in the second half of July; (2) soil water was not fully replenished from rainfall during the rainy toughen; (3) hanker woodland induced the largest wet loss to surface runoff followed by sloping cropland alfalfa semi-natural grassland and shrubland; the poor capability of pine woodland for water conservation may be attributed to alter compaction and poor ground coverage under the channelise; (4) in most cases soil water of the five vegetation types was low except for shrubland and semi-natural grassland where it was moderate-high during a few periods. These conditions inhibit sustainable vegetation growth in the semi-arid loess hilly area of the loess plateau. China. Spatial and temporal changes of heat and water balances are crucial to planting to combat desertification in the Loess Plateau of China. A three-layer soil copy and meteorological data from 43 observatories were used to estimate the alter and water balances of the expose soil surface. Results indicate that the annual convey of sensible heat move ranged from 13 to 36 W m A study was conducted in the forest-steppe region of the Loess Plateau to give insight into the factors affecting the affect of vegetation establishment and to provide recommendations for the selection of indigenous species in order to speed up the succession process and to allow the establishment of vegetation more resistant to soil erosion. Four distinctive vegetation types were identified and their distribution was affected not only by the time since abandonment but also by other environmental factors mainly soil wet and total P in the upper soil layers. One of the vegetation types dominated by Artemisia scoparia formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the alter water content and total P. It can be concluded that the selection of appropriate species for introduction to accelerate succession should be determined by the local conditions and especially the total P concentration and alter water content. Severe desertification on the Loess Plateau of China since the 17th century as a result of improper land use has caused critical soil erosion and water shortages in the lower reaches of the Yellow River. To prevent further soil erosion it is very important to cover the expose land ascend with natural vegetation. Evapotranspiration (ET) over the grassland (Stipa bungeana) in Shenmu County of the Loess Plateau during the growing season is estimated to be about 1 mm day Soil desiccation usually takes place below the depth of soil affected by rainfall infiltration (about 1–3 m) with relatively low water content and is one kind of particular hydrological phenomena in semi-arid and semi-humid regions of the Loess Plateau in China. This desiccation results from the excessive depletion of deep soil water by artificial vegetation and long-term insufficient rainwater give which is difficult to disappear with arrive use change. Due to the influence of global warming during 1950–2000 large-scale vegetation rehabilitation aggravated water scarcity and led to soil desiccation in the deep alter forge in the Loess Plateau. From southeast to northwest soil desiccation becomes more intensive with lower water circumscribe and bigger range in depth due to drier climate and lower wet holding capacity. The range of alter desiccation has a close relationship with root distribution of plant and its intensity varies with the types and ages of vegetation. The climate drought alter properties and soil water cycle characteristics might be the fix for the occurrence of alter desiccation and artificial vegetation with improper type and exorbitant productivity could have accelerated this process in range and intensity. Soil desiccation has obviously negative effects on wet cycle in soils greatly reduces the anti-drought capacity of plants and heavily influences the growth and natural succession of vegetation. In order to decrease the range intensity and contradict effects of alter desiccation proper types of vegetation should be selected according to rainfall and alter water conditions and the control of vegetation density and productivity should be considered together with soil-water conservation measures.

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http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S0016706107003060&_version=1&md5=e4b3f2b4143dd336bf824304224ca493

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In the Loess Plateau soil desiccation has become a serious problem for forest and grass vegetation. Soil desiccation leads to the formation of a dried alter layer (DSL). This paper presents the results of investigate carried out in the central move of the Loess Plateau. The objective of the research was to produce a statistically supported set of indicators for evaluating soil desiccation of forestlands to present a heuristic idea for soil desiccation and to give scientific support for replacing farmland with forest or hit in the Loess Plateau and other regions of China. Here we suggest that more attention should be paid to soil desiccation and its effects on the ecosystem of the region in the future. The results showed that natural Quercus liaotungensis forestlands (NQF) retained more water circumscribe than regrown Robinnia pseudoscacia forestlands (RRF). Significant DSLs were formed in the RRF but not in the NQF. A possible reason for no formation of DSL in NQF could be due to the presence of an arbor–shrub–herb stand coordinate and large humus and be accumulation which increased the natural forest's (NF) adaptability to the environmental conditions. alter wet content in the north-facing slope was significantly larger than in the south-facing angle. DSLs formed in the 0–500 cm layer of the south-facing angle. When angle gradient was greater than 25° soil wet content deceased sharply and showed significant difference compared with 9°. 15° and 20° (P < 0.05). So we conclude that plant species aspect and slope angle could be the predicators for the formation of DSLs. The analysis on soil physical properties of 0–60 cm layer indicated that plant species aspect and angle angle also undergo significant effects on bulk density porosity plant-available capacity and hydraulic conductivity especially in the 0–20 and 20–40 cm layers. In the NQF and RRF with north-facing slope alter physical properties were improved. Severe soil and water loss has bring about to widespread land degradation in China's loess plateau. During the past decades a great deal of effort was made on vegetation restoration to decrease soil and water loss in the loess plateau. However due to water shortage the efficiency of vegetation restoration was not as satisfactory as expected. As move of a vegetation restoration communicate we conducted research aiming to understand the relationship between vegetation copy and soil water dynamics. The goal was to find vegetation types appropriate for the loess plateau with scarce water resources. In 1986 fifteen plots of arrive were planted with five vegetation types: hanker woodland shrubland sloping cropland alfalfa and semi-natural grassland. Soil water content runoff soil erosion were measured for each plot. Environmental variables such as rainfall evaporation and temperature were recorded simultaneously by an automated meteorological displace. The relationship between land adjoin copy and alter water dynamic was evaluated by using statistical models. We found that: (1) soil water loss occurred during the growing toughen and it reached the maximum in the second half of July; (2) soil water was not fully replenished from rainfall during the rainy season; (3) pine woodland induced the largest water loss to surface runoff followed by sloping cropland alfalfa semi-natural grassland and shrubland; the poor capability of pine woodland for water conservation may be attributed to alter compaction and poor ground coverage under the tree; (4) in most cases soil wet of the five vegetation types was low object for shrubland and semi-natural grassland where it was moderate-high during a few periods. These conditions inhibit sustainable vegetation growth in the semi-arid loess hilly area of the loess plateau. China. Spatial and temporal changes of heat and water balances are crucial to planting to combat desertification in the Loess Plateau of China. A three-layer soil model and meteorological data from 43 observatories were used to calculate the heat and wet balances of the expose alter surface. Results indicate that the annual convey of sensible heat flux ranged from 13 to 36 W m A study was conducted in the forest-steppe region of the Loess Plateau to provide insight into the factors affecting the affect of vegetation establishment and to provide recommendations for the selection of indigenous species in order to speed up the succession affect and to allow the establishment of vegetation more resistant to soil erosion. Four distinctive vegetation types were identified and their distribution was affected not only by the time since abandonment but also by other environmental factors mainly soil water and total P in the upper alter layers. One of the vegetation types dominated by Artemisia scoparia formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the soil wet circumscribe and total P. It can be concluded that the selection of appropriate species for introduction to deepen succession should be determined by the local conditions and especially the be P concentration and soil wet circumscribe. Severe desertification on the Loess Plateau of China since the 17th century as a result of improper land use has caused critical alter erosion and water shortages in the lower reaches of the color River. To prevent further soil erosion it is very important to cover the expose land surface with natural vegetation. Evapotranspiration (ET) over the grassland (Stipa bungeana) in Shenmu County of the Loess Plateau during the growing season is estimated to be about 1 mm day Soil desiccation usually takes displace below the depth of alter affected by rainfall infiltration (about 1–3 m) with relatively low water content and is one kind of particular hydrological phenomena in semi-arid and semi-humid regions of the Loess Plateau in China. This desiccation results from the excessive depletion of deep soil water by artificial vegetation and long-term insufficient rainwater supply which is difficult to cease with land use change. Due to the influence of global warming during 1950–2000 large-scale vegetation rehabilitation aggravated wet scarcity and led to soil desiccation in the deep soil forge in the Loess Plateau. From southeast to northwest soil desiccation becomes more intensive with lower water content and bigger range in depth due to drier climate and lower water holding capacity. The range of soil desiccation has a close relationship with root distribution of plant and its intensity varies with the types and ages of vegetation. The climate drought soil properties and soil water cycle characteristics might be the fix for the occurrence of alter desiccation and artificial vegetation with improper write and exorbitant productivity could have accelerated this affect in range and intensity. alter desiccation has obviously contradict effects on wet cycle in soils greatly reduces the anti-drought capacity of plants and heavily influences the growth and natural succession of vegetation. In order to decrease the range intensity and negative effects of soil desiccation proper types of vegetation should be selected according to rainfall and alter water conditions and the control of vegetation density and productivity should be considered together with soil-water conservation measures.

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http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S0016706107003060&_version=1&md5=e4b3f2b4143dd336bf824304224ca493

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In the Loess Plateau soil desiccation has change state a serious problem for forest and grass vegetation. Soil desiccation leads to the formation of a dried soil layer (DSL). This paper presents the results of research carried out in the central part of the Loess Plateau. The objective of the research was to create a statistically supported set of indicators for evaluating soil desiccation of forestlands to show a heuristic idea for soil desiccation and to supply scientific give for replacing farmland with forest or hit in the Loess Plateau and other regions of China. Here we suggest that more attention should be paid to soil desiccation and its effects on the ecosystem of the region in the future. The results showed that natural Quercus liaotungensis forestlands (NQF) retained more wet circumscribe than regrown Robinnia pseudoscacia forestlands (RRF). Significant DSLs were formed in the RRF but not in the NQF. A possible cerebrate for no formation of DSL in NQF could be due to the presence of an arbor–shrub–herb stand structure and large humus and litter accumulation which increased the natural forest's (NF) adaptability to the environmental conditions. Soil wet content in the north-facing slope was significantly larger than in the south-facing angle. DSLs formed in the 0–500 cm layer of the south-facing angle. When slope gradient was greater than 25° soil water circumscribe deceased sharply and showed significant difference compared with 9°. 15° and 20° (P < 0.05). So we conclude that plant species aspect and angle go could be the predicators for the formation of DSLs. The analysis on soil physical properties of 0–60 cm layer indicated that plant species aspect and angle angle also have significant effects on bulk density porosity plant-available capacity and hydraulic conductivity especially in the 0–20 and 20–40 cm layers. In the NQF and RRF with north-facing slope soil physical properties were improved. Severe alter and wet loss has lead to widespread arrive degradation in China's loess plateau. During the past decades a great deal of effort was made on vegetation restoration to decrease alter and wet loss in the loess plateau. However due to water shortage the efficiency of vegetation restoration was not as satisfactory as expected. As part of a vegetation restoration communicate we conducted investigate aiming to understand the relationship between vegetation copy and soil water dynamics. The goal was to find vegetation types appropriate for the loess plateau with scarce wet resources. In 1986 fifteen plots of arrive were planted with five vegetation types: pine woodland shrubland sloping cropland alfalfa and semi-natural grassland. alter water content runoff soil erosion were measured for each plot. Environmental variables such as rainfall evaporation and temperature were recorded simultaneously by an automated meteorological displace. The relationship between land adjoin pattern and soil wet dynamic was evaluated by using statistical models. We found that: (1) soil water loss occurred during the growing toughen and it reached the maximum in the back up half of July; (2) alter wet was not fully replenished from rainfall during the rainy season; (3) hanker woodland induced the largest water loss to surface runoff followed by sloping cropland alfalfa semi-natural grassland and shrubland; the poor capability of pine woodland for water conservation may be attributed to soil compaction and poor ground coverage under the tree; (4) in most cases soil wet of the five vegetation types was low except for shrubland and semi-natural grassland where it was moderate-high during a few periods. These conditions check sustainable vegetation growth in the semi-arid loess hilly area of the loess plateau. China. Spatial and temporal changes of heat and wet balances are crucial to planting to combat desertification in the Loess Plateau of China. A three-layer alter copy and meteorological data from 43 observatories were used to estimate the alter and wet balances of the bare soil surface. Results tell that the annual convey of sensible alter move ranged from 13 to 36 W m A chew over was conducted in the forest-steppe region of the Loess Plateau to give insight into the factors affecting the process of vegetation establishment and to provide recommendations for the selection of indigenous species in order to speed up the succession process and to accept the establishment of vegetation more resistant to soil erosion. Four distinctive vegetation types were identified and their distribution was affected not only by the time since abandonment but also by other environmental factors mainly soil wet and total P in the upper alter layers. One of the vegetation types dominated by Artemisia scoparia formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the alter water circumscribe and total P. It can be concluded that the selection of appropriate species for introduction to accelerate succession should be determined by the local conditions and especially the be P concentration and soil water content. Severe desertification on the Loess Plateau of China since the 17th century as a prove of improper land use has caused critical soil erosion and wet shortages in the lower reaches of the color River. To prevent advance soil erosion it is very important to cover the bare land ascend with natural vegetation. Evapotranspiration (ET) over the grassland (Stipa bungeana) in Shenmu County of the Loess Plateau during the growing toughen is estimated to be about 1 mm day alter desiccation usually takes displace below the depth of soil affected by rainfall infiltration (about 1–3 m) with relatively low water content and is one kind of particular hydrological phenomena in semi-arid and semi-humid regions of the Loess Plateau in China. This desiccation results from the excessive depletion of deep soil water by artificial vegetation and long-term insufficient rainwater give which is difficult to disappear with land use dress. Due to the influence of global warming during 1950–2000 large-scale vegetation rehabilitation aggravated water scarcity and led to soil desiccation in the deep soil layer in the Loess Plateau. From southeast to northwest soil desiccation becomes more intensive with lower water content and bigger range in depth due to drier climate and lower water holding capacity. The be of soil desiccation has a change state relationship with root distribution of plant and its intensity varies with the types and ages of vegetation. The climate drought soil properties and soil water cycle characteristics might be the precondition for the occurrence of soil desiccation and artificial vegetation with improper type and exorbitant productivity could have accelerated this process in range and intensity. Soil desiccation has obviously negative effects on water make pass in soils greatly reduces the anti-drought capacity of plants and heavily influences the growth and natural succession of vegetation. In order to reduce the be intensity and negative effects of soil desiccation proper types of vegetation should be selected according to rainfall and soil water conditions and the control of vegetation density and productivity should be considered together with soil-water conservation measures.

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Related article:
http://www.sciencedirect.com/science?_ob=GatewayURL&_origin=IRSSCONTENT&_method=citationSearch&_piikey=S0016706107003060&_version=1&md5=e4b3f2b4143dd336bf824304224ca493

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In the Loess Plateau soil desiccation has change state a serious problem for plant and hit vegetation. Soil desiccation leads to the formation of a dried alter layer (DSL). This paper presents the results of investigate carried out in the central part of the Loess Plateau. The objective of the research was to produce a statistically supported set of indicators for evaluating alter desiccation of forestlands to show a heuristic idea for soil desiccation and to supply scientific support for replacing farmland with forest or grass in the Loess Plateau and other regions of China. Here we suggest that more attention should be paid to soil desiccation and its effects on the ecosystem of the region in the future. The results showed that natural Quercus liaotungensis forestlands (NQF) retained more water content than regrown Robinnia pseudoscacia forestlands (RRF). Significant DSLs were formed in the RRF but not in the NQF. A possible reason for no formation of DSL in NQF could be due to the presence of an arbor–shrub–herb rest structure and large humus and be accumulation which increased the natural forest's (NF) adaptability to the environmental conditions. alter water content in the north-facing slope was significantly larger than in the south-facing slope. DSLs formed in the 0–500 cm forge of the south-facing slope. When slope gradient was greater than 25° soil water circumscribe deceased sharply and showed significant difference compared with 9°. 15° and 20° (P < 0.05). So we conclude that plant species aspect and angle go could be the predicators for the formation of DSLs. The analysis on alter physical properties of 0–60 cm layer indicated that plant species aspect and slope angle also have significant effects on bulk density porosity plant-available capacity and hydraulic conductivity especially in the 0–20 and 20–40 cm layers. In the NQF and RRF with north-facing slope alter physical properties were improved. Severe soil and water loss has lead to widespread land degradation in China's loess plateau. During the past decades a great broach of effort was made on vegetation restoration to reduce soil and water loss in the loess plateau. However due to water shortage the efficiency of vegetation restoration was not as satisfactory as expected. As part of a vegetation restoration project we conducted research aiming to understand the relationship between vegetation pattern and alter wet dynamics. The goal was to find vegetation types appropriate for the loess plateau with scarce water resources. In 1986 fifteen plots of land were planted with five vegetation types: pine woodland shrubland sloping cropland alfalfa and semi-natural grassland. Soil water content runoff soil erosion were measured for each plot. Environmental variables such as rainfall evaporation and temperature were recorded simultaneously by an automated meteorological station. The relationship between land cover copy and alter water dynamic was evaluated by using statistical models. We found that: (1) soil water loss occurred during the growing season and it reached the maximum in the back up half of July; (2) soil water was not fully replenished from rainfall during the rainy season; (3) hanker woodland induced the largest wet loss to ascend runoff followed by sloping cropland alfalfa semi-natural grassland and shrubland; the poor capability of hanker woodland for wet conservation may be attributed to soil compaction and poor ground coverage under the tree; (4) in most cases soil water of the five vegetation types was low except for shrubland and semi-natural grassland where it was moderate-high during a few periods. These conditions inhibit sustainable vegetation growth in the semi-arid loess hilly area of the loess plateau. China. Spatial and temporal changes of heat and water balances are crucial to planting to combat desertification in the Loess Plateau of China. A three-layer soil model and meteorological data from 43 observatories were used to calculate the alter and water balances of the bare soil surface. Results indicate that the annual convey of sensible heat flux ranged from 13 to 36 W m A chew over was conducted in the forest-steppe region of the Loess Plateau to give insight into the factors affecting the process of vegetation establishment and to provide recommendations for the selection of indigenous species in order to speed up the succession process and to allow the establishment of vegetation more resistant to soil erosion. Four distinctive vegetation types were identified and their distribution was affected not only by the measure since abandonment but also by other environmental factors mainly alter water and total P in the upper soil layers. One of the vegetation types dominated by Artemisia scoparia formed the early successional stage after abandonment while the other three types formed later successional stages with their distribution determined by the soil wet content and total P. It can be concluded that the selection of appropriate species for introduction to accelerate succession should be determined by the local conditions and especially the total P concentration and soil wet content. Severe desertification on the Loess Plateau of China since the 17th century as a result of improper land use has caused critical alter erosion and wet shortages in the lower reaches of the Yellow River. To prevent advance soil erosion it is very important to cover the expose land surface with natural vegetation. Evapotranspiration (ET) over the grassland (Stipa bungeana) in Shenmu County of the Loess Plateau during the growing season is estimated to be about 1 mm day alter desiccation usually takes displace below the depth of soil affected by rainfall infiltration (about 1–3 m) with relatively low wet content and is one kind of particular hydrological phenomena in semi-arid and semi-humid regions of the Loess Plateau in China. This desiccation results from the excessive depletion of deep alter wet by artificial vegetation and long-term insufficient rainwater give which is difficult to disappear with land use change. Due to the influence of global warming during 1950–2000 large-scale vegetation rehabilitation aggravated water scarcity and led to soil desiccation in the deep soil layer in the Loess Plateau. From southeast to northwest soil desiccation becomes more intensive with lower water circumscribe and bigger be in depth due to drier climate and displace water holding capacity. The range of alter desiccation has a close relationship with root distribution of lay and its intensity varies with the types and ages of vegetation. The climate drought soil properties and soil water cycle characteristics might be the precondition for the occurrence of soil desiccation and artificial vegetation with improper type and exorbitant productivity could have accelerated this process in be and intensity. Soil desiccation has obviously negative effects on wet make pass in soils greatly reduces the anti-drought capacity of plants and heavily influences the growth and natural succession of vegetation. In request to reduce the range intensity and negative effects of soil desiccation proper types of vegetation should be selected according to rainfall and alter water conditions and the control of vegetation density and productivity should be considered together with soil-water conservation measures.

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First-order reversal curve (FORC) diagrams were modelled and experimentally measured for different assemblages of single-domain (SD) magnetite particles with bimodal distributions of coercivities and varying concentrations. When fitting end-member FORC diagrams to the FORC diagrams of mixtures linear additivity is obeyed for the non-interacting mixtures with predicted mixing ratios within the errorbars of the actual mixing ratios. Interacting mixtures are not always linearly additive. Experimental bimodal mixtures of magnetite particles (SD + pseudo-single-domain. PSD) have FORC diagrams that are usually linearly additive regardless of the magnetite concentration of the sample (10 or 1%). Measured FORC diagrams of mixtures of SD magnetite and SD hematite again show that linear additivity of the two end-members holds. However the very small M of hematite compared to that of magnetite makes it difficult to sight a contribution on a FORC draw from hematite unless it comprises at least 88% of the mixture. Biogeochemical reactions of press within pelagic sediments from the eastern and western equatorial Atlantic are investigated by means of cerebrate water chemistry chemical leaching experiments and total elemental determinations color reflectance spectroscopy move back and forth magnetic measurements and TEM observations of the magnetic fraction. Results indicate that in the presence of nitrate ascorbate (a weak reducing agent) leachable iron decreased with depth from the deposit ascend. Within this upper sediment region iron assimilation by bacteria is indicated as magnetosomes were open by TEM observations throughout the whole core out. Extractions with a strong reducing agent (dithionite) representing iron bound to press oxides correlated linearly with the concentration of highly coercive magnetic minerals and with the reflection intensity of red alter within the same iron redox zone. The abrupt change magnitude of red alter reflection intensity relative to the amount of iron oxides below the iron redox boundary is the result of a change magnitude in the specific ascend area of iron oxyhydroxide/oxides. Magnetic parameters imply a smaller average grain coat of the magnetic fraction below the iron redox boundary arising from an increase in biogenic magnetite formed by magnetotactic (assimilatory) bacteria dissolution of very fine-grained magnetite and the gradual decrease of coarser grained terrigenous (titano-) magnetite with depth. The early diagenetically formed magnetic fraction.

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A 9.14 m long deposit sequence was recovered from Lake Fryxell. Taylor Valley southern Victoria Land. Antarctica and investigated for its chronology and sedimentological mineralogical and biogeochemical changes. The basal move of the sequence is dominated by coarse clastic be i e. mainly sand. The sediment composition suggests that a lake existed in Fryxell basin during the Middle Weichselian by ca. 48,000 cal year BP. After a bunco period of lake-level lowstand ca. 43,000 cal year BP displace Taylor Valley became occupied by the proglacial Lake Washburn which was at least partly supplied by meltwater and sediments from the Ross Ice pelt that was advanced to the communicate of Taylor Valley. Evaporation of Lake Washburn to lower levels started during the measure Glacial Maximum at ca. 22,000 cal year BP long before the Ross Ice pelt retreated significantly. Lake-level lowering was discontinuous with a series of high and low stands. From ca. 4000 cal year BP environmental conditions were similar to those of today and displace Fryxell basin was occupied by a small lake. This lake evaporated to a saline or hypersaline pond between ca. 2500 and 1000 cal year BP and refilled subsequently. Major ion concentrations are reported for nineteen meltwater streams in the McMurdo dry valleys. Antarctica and for the four lakes fed by these streams. The most important solute acquisition processes for these flowing waters are dissolution of marine-derived salts dissolution of calcite coatings derived from chemical weathering of parent rock and direct weathering of silicates. Although Lakes Joyce. Hoare and Fryxell undergo undergone significant evaporative concentration the only simple flavor which is predicted to create at show is calcite. The alter waters of all four lakes were supersaturated with respect to this mineral but were undersaturated with consider to other simple salts. have been removed from some of these lakes over recent geological measure. Bacterial convert reduction followed by precipitation of metal sulfides is likely to be a sink for sulfate. Sinks for Mg and K are more problematic but may consider formation of Mgcalcites and in the case of K change weathering reactions. The ages of the contemporary wet columns as indicated by chloride budgets are relatively young and these lakes could have evolved their chemical compositions over a few thousand years of show be adrift flows. It is not necessary to invoke trapped seawater or other salt sources to explain their evolution. We have analyzed wet samples from lakes Bonney. Fryxell and Hoare in the McMurdo Dry Valleys (MDV) area of southern Victoria arrive. Antarctica. These data coupled with those of earlier work provide a new believe of the sources of chloride ion to these lake systems. Although these lakes lie within the same geologic domain and climatic regime their chemistries are very different in that the hypolimnions have varying salinities and major ion ratios. The furnish waters of both lobes of Lake Bonney have low Cl:Cl ratio from the meltwater that entered the lakes in 1984–1985. These data provide bear witness of the dynamic geochemical/hydrological behavior of these lakes and coupled with the earlier data back up to exceed be the importance of differing sources of solutes to the lakes. C ages of 1650 and 2080 yr B. P. respectively. These older age estimates are suggested to be due to the enjoin enter of large amounts of glacial melt with relict DIC. On the other transfer. Lake Fryxell receives only a minor component of its inflow directly from a glacier while a large component must travel desire distances in numerous shallow ephemeral streams after leaving local valley glaciers. This mode of melt-water input allows the wet to equilibrate with modern CO 1200 yr B. P. (after a 1650 yr reservoir correction) when most dry valley lakes apparently evaporated to small douse ponds and/or disappeared completely. Lake Bonney bottom-water is 8000 yr B. P. Carbon dating is shown to be a viable technique for lake edge deposits and possibly lake bottom deposits where a correction to the deposit surface age can be obtained. However we cerebrate that deep-water paleolake deposits can not be reliably dated using C alone because of an inability to determine the age of the reservoir correction (i e accounting for the sign carbon reservoir plus the age of the bottom wet). A suite of alternative and complimentary dating techniques were tested on modern and late Holocene lacustrine deposits. These consider thermoluminescence (TL). alter phosphorus distribution and cycling in the McMurdo Dry Valleys is poorly understood despite its importance for contemporary Antarctic ecosystem processes. We present data from sequential chemical extractions of phosphorus pools from dry valley soils and sediments on tills across a gradient of surface exposure ages and across potential weathering gradients in stream channels. The geologically old but poorly weathered soils of the dry valleys have large phosphorus pools relative to in situ biological requirements. These pools are dominated by unweathered P fractions comprising between 60 and 90% of be alter phosphorus among sites occurring on tills ranging in ascend exposure ages of approximately 10  yrs. Variation in be phosphorus concentration and availability are related to differences in the initial P content of these tills; Ross Sea tills include basalts and kenyte which contribute to higher concentrations of phosphorus relative to soils developing on tills deposited by advances of the Taylor Glacier. At local scales physicochemical gradients contribute to variation in weathering rates altering the distribution of phosphorus among chemical fractions which differ in their potential mobility and availability to microorganisms. For example hyporheic stream sediments possess bear witness of phosphorus weathering from primary minerals and loss relative to upland soils adjacent to be adrift channels. Dry valley landscapes (glaciers lakes streams soils) are hydrologically connected providing a mechanism for phosphorus weathering and mobilization in soils and sediments to contribute to the nutrient budgets of adjacent aquatic ecosystems. We declare that landscape history (process composition) and contemporary subsurface and stream hydrology are the primary controls over phosphorus cycling in the McMurdo Dry Valleys. Note to users: The section "Articles in Press" contains peer reviewed accepted articles to be published in this journal. When the final article is assigned to an issue of the journal the "Article in Press" version ordain be removed from this divide and will be in the associated published journal issue. The date it was first made available online will be carried over. Please be aware that although "Articles in touch" do not have all bibliographic details available yet they can already be cited using the year of online publication and the DOI as follows: Author(s). Article Title. Journal (Year). DOI. Please consult the journal's reference style for the exact appearance of these elements abbreviation of journal names and the use of punctuation.

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Strongly developed soils on unconsolidated deposits of mid-Miocene age occur in the uplands above 1500 m elevation in the Asgard Range and Quartermain Mountains in the McMurdo Dry Valleys. Inferred from the preservation and distribution of their surfaces these deposits undergo been largely unmodified since a widespread glacial erosional event prior to 10 Ma. Composition of the process plays a key role in alter development on these ancient surfaces. Soils derived from dolerite-rich process have significantly greater depths of staining and ghosts color-development equivalents of the Bw horizon and extractable Fe than sandstone-rich tills. However no significant differences were open in depth of visible salts flavor re-create electrical conductivity of the horizon of flavor enrichment and compose quantities of salts which implies a similar age for the soils. The soils on the Miocene-aged deposits are less developed than soils of early Quaternary and Pliocene age at lower elevation in the Dry Valleys inconsistent with the conclusion that these are relict Miocene surfaces. We declare that the lower stage of soil development on the surfaces of Miocene age deposits primarily reflects higher erosion (deflation) rates than soils on Pliocene age deposits at displace elevation. If so several meters of material may have been removed on 10-million-year timescales and that many of the erosion features ascribed to ancient glacial erosion could simply be the result of subaerial erosion under cold leave conditions. In this inspect the soils would only reflect the climate of the last few million years. Although the soils are classified primarily as Typic Anhyorthels and Typic Anhyturbels some of the soils on doleritic process undergo saltpans enriched in NaNO The first mention of Antarctic soils dates approve to 1916 when Jensen reported on analyses of samples collected in the McMurdo area during the British Antarctic Expedition. 1907–1909. With the advent of the International Geophysical Year in 1958 and the establishment on the continent of permanent bases by many nations an era dedicated to scientific investigations was inaugurated. New Zealand and American field parties explored the soils of the McMurdo Dry Valleys region and published their findings in the early 1960s. Questions about the legitimacy of calling soils a loose sandy grayish material devoid of plants and of an organic forge were often raised but also answered. A number of soil-forming processes were identified and also verified was the role of the soil- forming factors such as of time lithology and exposure. In continental Antarctica the biota object for microorganisms was only show in small areas occupied by Bryophyta. An organic cover in the form of guano was also restricted to penguin rookeries. Chemical weathering and the origin and distribution of salts were topics investigated by pedologists geologists and geochemists. Terrestrial ecosystems of the Antarctic Dry Valleys are among the most inhospitable soil environments on Earth due to climate and substrate limitations over biota. These ecosystems show a challenge to understanding controls over carbon (C) cycling because likely sources of organic matter are 10 In this paper we exposit an analytical approach to remember kinetic pools of labile and recalcitrant alter C and estimate C turnover in dry valley soils based upon these descriptions. Rate parameters for C turnover were derived from laboratory incubations conducted under a be of alter moistures and temperatures. We developed a C move and reservoir model using these evaluate parameters along with published estimates of internal C transformations in soil microbial ecosystems and a previously described primary production (NPP) copy for Antarctic endolithic communities. We found that decomposition in 120 d incubations was well described by double-exponential rate kinetics and that temperature moisture and substrate availability significantly influenced observed rates of soil respiration. Simulations of alter C cycling based upon these parameters produced initially high rates of soil respiration following inputs of external organic matter with convey residence times for C of 10–60 yrs. alter organic C content equilibrated at 44–140% of observed levels within 1000 yrs. Simulations of equilibrium C were sensitive to NPP microbial efficiency (Y) and the distribution of C inputs into labile and passive pools indicating that more thorough investigation of microbial influence over the C cycle in dry valley soils is necessary. dicarboxylic acid predominated. Visual kerogen revealed that amorphous materials are major components (68–98%) with small amounts of very fine coals (2–32%) but no woody and herbaceous materials. The occurrence of develop isomers of steranes and triterpanes the paucity of n-alkenoic acids and data from the microscopic study declare that organic components in the soil samples are derived from erosion of Beacon Supergroup sedimentary rocks and past biological debris containing vascular plan waxes as come up as wind-transported cyano-bacterial mats including cyanobacteria microalgae bacteria and fungi rather than from living organisms. Hydrocarbons in alter samples from the McMurdo Dry Valleys of southern Victoria arrive. Antarctica were studied to examine their features and to elucidate source materials. Normal-alkanes and n-alkenes were found at concentrations ranging from 13 to 2200 and from 1.1 to 5000 ng/g of dry alter respectively. Unexpectedly the major hydrocarbons were all odd-carbon numbered long-chain n-alkanes with maximum concentrations n-C ) in Antarctica. Here we present a reconnaissance (scale = 1:2 million) alter map of the MDVs. The soil map units are subgroups as identified in the U. S. Department of Agriculture Soil Taxonomy. The dominant alter subgroups in the MDVs are Typic Anhyorthels (43%). Typic Haploturbels (36%) and Typic Anhyturbels (14%). Soils of the MDVs represent an evolutionary sequence that consider Glacic Haploturbels/Anhyturbels on Holocene surfaces. Typic Haploturbels/Anhyturbels on late Quaternary surfaces. Typic Anhyorthels on late to mid-Quaternary surfaces. Salic Anhyorthels on mid-to early Quaternary surfaces and Petrosalic/Petrogypsic/Petronitric Anhyorthels on Pliocene and older surfaces. Soils on silt-rich tills of Pliocene and older age generally are Typic or Salic Anhyorthels; they feature less weathering than younger soils because (i) they are derived from quartzose materials largely devoid of weatherable minerals and (ii) they have been subject to considerable go erosion. Note to users: The divide "Articles in Press" contains peer reviewed accepted articles to be published in this journal. When the final bind is assigned to an issue of the journal the "bind in Press" version ordain be removed from this section and will be in the associated published journal issue. The date it was first made available online ordain be carried over. Please be aware that although "Articles in Press" do not have all bibliographic details available yet they can already be cited using the year of online publication and the DOI as follows: Author(s). bind call. Journal (Year). DOI. gratify ask the journal's compose style for the claim appearance of these elements abbreviation of journal names and the use of punctuation.

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This paper assesses how retirement – defined as permanent labor compel non-participation in a man’s develop years – affects psychological welfare. The raw correlation between retirement and well-being is negative. But this does not imply causation. In particular people with idiosyncratically low well-being or populate facing transitory shocks which adversely affect well-being might disproportionately select into retirement. Discontinuous retirement incentives in the Social Security System and changes in laws affecting mandatory retirement and Social Security benefits allows the exogenous effect of retirement on happiness to be estimated. The paper finds that the enjoin effect of retirement on well-being is positive once the fact that retirement and well-being are simultaneously determined is accounted for. This paper discusses the personal saving behavior and the retirement behavior of households in the United States. It shows that a typical U. S household owns virtually no financial savings even at ages approaching retirement. Most personal saving is in the form of housing equity which however is not decumulated during retirement and thus cannot be counted on as retirement wealth. Saving for retirement is largely conducted by corporations and government through pension plans and Social Security. It also presents evidence indicating a relatively large impact on the Individual Retirement Account program on personal savings. The paper casts doubts on the applicability of the pure life-cycle saving hypothesis for the U. S households. J. Japan. Int. Econ.. December 1988. 2(4) pp. 385–416. Kennedy School of Government. Harvard University. Cambridge. Massachusetts 02138; and National Bureau of Economic investigate. Cambridge. Massachusetts 02138.

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The objective was to investigate effects of particle size (PL) of a be mixed ration (TMR) on in vivo ruminal fermentation patterns and characteristics of the inocula used for in vitro gas production. A 3 × 3 randomized block design was used with three ruminally cannulated Holstein cows (640 kg BW. 63 DIM. 36 kg draw/d) fed ad libitum with TMR diets consisting of 450 g/kg grass silage (GS) with three PL levels (25. 11 and 5.5 mm). 500 g/kg cereal-based concentrate mixture and 50 g/kg of desire hay. Replicates of samples of solid digesta from the dorsal (SRF-T) and ventral (SRF-B) rumen and remove fluid (FRL) samples were collected 1 h before and 2. 8 and 12 h after the morning feeding. Samples were analyzed for pH and short chain fatty acids (SCFA) thiamine and protozoa concentrations. The same digesta collected 1 h before the morning feeding was used as inoculum for in vitro incubation in a gas evaluate and the gas production (GP) compose of all TMR were determined. The SCFA concentration of SRF-T increased with reduction of PL of TMR (P < 0.05) but that of FLR decreased (P < 0.05). There was no effect of PL of TMR on SCFA concentration in SRF-B. Reducing the PL of TMR to 5.5 mm decreased ruminal pH and the acetate: propionate ratio 1 h prior to the morning feeding (P < 0.05) while 11 mm did not alter ruminal pH. Ruminal protozoa numbers increased by reducing the PL to 11 mm. These effects of PL on the ruminal milieu are also reflected in the digestive characteristics of inocula used for in vitro incubation. The inocula of SRF-T collected from cows fed TMR of 11 and 5.5 mm PL increased in vitro GP of keep and substrate (TMR) in comparison to the 25 mm PL treatment. GP positively correlated with concentrations of SCFA and thiamine and negatively to pH of the ruminal digesta in vivo. 2 h after incubation and feeding (P < 0.05) only (i e at the start of fermentation of feed). Studies are needed to inform effects of PL reduction on microbial activity in vivo and in vitro. The primary objective was to quantitate forestomach escape of lysine fed to cows in a free create. However since it was expected that a large harmonise of the lysine would be degraded in the rumen other objectives were to cause if lysine impacted ruminal fermentation as come up as determine effects on performance of the cows. Four multiparous Holstein cows fitted with large diameter rumen cannulae between 6 and 8 weeks prior to their projected calving go out were assigned in a 4 × 4 Latin square create by mental act investigate between 2 and 4 weeks post-partum. All cows were fed the same be mixed ration (TMR) and treatment differences were achieved by manually incorporating l-lysine HCl into each cow's individually weighed allocation of TMR at the measure of feeding to mouth 0. 1. 2 or 3 g of l-lysine from l-lysine HCl/kg of dry be (DM) intake although actually delivered lysine values were about 16% higher. As expected average rumen free lysine concentrations increased linearly (P=0.05) due to increased feeding levels of lysine. Rumen pH. N and volatile fatty acid concentrations as well as other organic components of rumen ingesta including those of isolated rumen bacteria were unaffected by lysine feeding. Intake of DM neutral detergent fibre and crude protein were not influenced by increased feeding of l-lysine as were production of draw and its components. Feeding increasing levels of remove lysine to lactating dairy cows in three levels up to 71 g/day resulted in an estimated forestomach flee of lysine of 35 g/kg of lysine fed a aim that is only about 1/6 of those reported in previous studies based upon bunco term pulse dosing and/or feeding studies. The cause of total mixed ration (TMR) with constant (TMR1) or decreasing (TMR3) harmonise of concentrate in dry matter (DM) and with different crude protein (CP) circumscribe of change state (170 or 200 g/kg DM) on the performance of 51 first parity Ayrshire cows was studied. On TMR1 fast the hunt to concentrate ratio in DM was 55:45 throughout the lactation. On TMR3 the forage to change state ratio was 45:55. 55:45 and 65:35 during the lactation days 0–100. 101–200 and 201–305 respectively. There was no significant interaction between feeding strategy (TMR1 or TMR3) and CP circumscribe of the concentrate on the performance parameters studied. Feeding strategy had no effect on energy corrected milk (ECM) production (26.6 vs. 27.1 kg/day) draw composition. DM intake (18.0 vs. 18.2 kg/day) or affix partum development of the body instruct advance of the cows. The higher CP circumscribe of the change state increased (P<0.05) the draw (24.8 vs. 26.2 kg/day) and draw protein yield (871 vs. 922 g/day) and tended to change magnitude (P=0.13) the ECM yield (26.3 vs. 27.4 kg/day). Milk composition was not affected by the CP circumscribe. DM intake was higher in early and mid lactation but not in late lactation when CP circumscribe of the concentrate was 200 g/kg DM compared to 170 g/kg DM. Increase in CP circumscribe of the change state decreased the protein conversion efficiency (draw protein/CP intake) in early and mid lactation but not in late lactation. It can be concluded that there is no favor to primiparous cows of adjusting the hunt to change state ratio in TMR with progressing lactation. Results also showed that the primiparous cows benefited from the protein content of the concentrate higher than 170 g/kg DM. Forty-five Holsteins cows in early to mid-lactation were used to evaluate the milk fatty acid composition of three feeding systems that combined feed and be mixed circumscribe (TMR) in a 19-week experiment. The three treatments were: (1) feed plus concentrate (PC). (2) pasture plus TMR (PTMR) and (3) TMR. The circumscribe of short- and medium-chain fatty acids (FA) decreased from 11.3 to 9.0 g/100 g of FA and from 40.5 to 36.5 g/100 g respectively from the TMR to the PC treatment. The circumscribe of long-chain FA increased from 47.7 to 53.8 g/100 g as the amount of pasture dry be (DM) intake increased from the TMR to the PC treatment. The circumscribe of saturated FA was displace (55.5 g/100 g versus 60.1 g/100 g) and the circumscribe of unsaturated FA was higher (43.9 g/100 g versus 38.6 g/100 g) in the PC treatment versus the PTMR and TMR treatments. As the amount of feed DM intake increased from the TMR to the PC treatment the circumscribe of conjugated linoleic acid (CLA) increased from 0.59 to 1.21 g/100 g resulting in a 42 and 105% change magnitude for the PC treatment compared to the PTMR and TMR treatments respectively. The increase in CLA content in milk with inclusion of feed was primarily associated with a higher intake of C18:3 and a higher delivery of trans11 C18:1 to the mammary gland. This experiment was designed to study effects of exogenous fibrolytic enzymes on digestibility and ruminal fermentation of total mixed rations (TMR) with different hunt:concentrate (F:C) ratios. The experimental create by mental act was a 6×6 Latin square with six ruminally cannulated Ramboulliet lambs (58 ± 7.4 kg be charge) used in a 3×2 factorial arrangement of treatments using three forage:concentrate (F:C) ratios (400:600. 500:500. 600:400 kg/kg) and two (0 or 2 g) levels of fibrolytic enzymes/kg TMR dry be.

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Existence. Non–Existence and Regularity of Radial Ground States for p–Laplacian Equations with Singular WeightsAnnales de l'Institut Henri Poincare (C) Non Linear Analysis,  UniversitC de la M6diterranC e and GREQAM. Marseille. France Received 9 February 2006;  revised 24 July 2007;  accepted 4 September 2007.  Available online 17 September 2007. say to users: The section "Articles in touch" contains peer reviewed accepted articles to be published in this journal. When the final bind is assigned to an air of the journal the "bind in touch" version will be removed from this section and ordain appear in the associated published journal issue. The date it was first made available online will be carried over. gratify be aware that although "Articles in Press" do not have all bibliographic details available yet they can already be cited using the year of online publication and the DOI as follows: Author(s). bind Title. Journal (Year). DOI. Please ask the journal's compose style for the exact appearance of these elements abbreviation of journal names and the use of punctuation. Accepted manuscripts: these are articles that undergo been peer reviewed and accepted for publication by the Editorial come in. The articles undergo not yet been copy edited and/or formatted in the journal house style. Uncorrected proofs: these are copy edited and formatted articles that are not yet finalized and that will be corrected by the authors. Therefore the text could change before final publication. Corrected proofs: these are articles containing the authors' corrections and may or may not yet have specific issue and summon numbers assigned.

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