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The hydrocarbon exploration shows that the Ordovician karst reservoirs in the western slope of the Shulu Sag are of great significance, but there is a lack of systematic research. The characteristics, main controlling factors, formation, and evolution model of the karst reservoirs were discussed based on cores, thin sections, well drilling and logging, 3D seismic, and production data, in combination with petrophysical property analysis. The results show that the karst reservoirs include micrite, crystalline dolomite, karst breccia, and other lithologies. The storage space is dominated by dissolution pores, caves, and fractures (i.e., tectonic fractures, dissolution fractures, and tectonic-dissolution fractures). However, the matrix is characterized by low porosity and permeability with great heterogeneity, and fractures enhance the percolation capacity of the reservoirs. The formation and distribution of the karst reservoirs are dominantly controlled by integrating tectonic, paleogeomorphology, and karst cycles. Tectonic movements are the key to dissolution development, karst paleogeomorphology controls the planar distribution of high-quality reservoirs, and their vertical distribution is governed by karst cycles. The monoclinic structure formed by Indosinian to Yanshan fold is the prerequisite for the later development of multi-phase karst alteration. During the Himalayan period, the upper slope areas developed high-quality reservoirs due to the dual alteration of vertical vadose and horizontal underflow zones controlled by paleogeomorphology and seasonal paleowater table change. Thus, the formation and evolution of the karst reservoirs, including six stages, were established in this study. This work may provide theoretical guidance for future favorable oil and gas exploration. [ABSTRACT FROM AUTHOR]

To explore the chemical characteristics and environmental factors of groundwater in the Hetao Irrigation Area of Inner Mongolia, five irrigation fields, including UulanBuh, Jiefangzha, Yongji, Yichang, and Wulat, were selected as the research area. From 72 groundwater observation wells, a total of 216 groundwater samples were collected throughout three typical periods： the end of freeze-thaw （March）, the middle of irrigation （July）, and the end of autumn watering （November）. Comprehensive methods were utilized, such as statistical analysis, Piper three-line diagram, Gibbs diagram, ion ratio, and principal component analysis, to explore the changes in the groundwater chemical environment and the environmental driving factors of groundwater component formation. The groundwater drinking suitability was evaluated using the water quality index （WQI）, and the irrigation suitability was analyzed using the USSL and Wilcox plots. The results indicated that the groundwater in the research areas was generally saline, and the total anion and cation concentrations in each period in ascending order were as follows： late freeze-thaw stage, late autumn irrigation stage, and mid-irrigation stage, with Na + and Cl - being the major contributing ions. The chemical type of groundwater was dominated by Cl-Na, followed by Cl·SO 4 -Ca·Mg and a coexistence with SO 4 -Ca·Mg, HCO 3 ·Cl-Na, HCO 3 -Na, and HCO 3 -Ca·Mg. Based on WQI values, the shallow groundwater in Hetao Irrigation District was mainly classified as Class IV and Class V, and the quality was poor in general. According to the USSL diagram and Wilcox diagram, the comprehensive evaluation results showed that the salinity and sodium concentration of shallow groundwater in the irrigation area were generally high. A total of 80.6% of the water samples during the late freeze-thaw period, 76.1% during the mid-irrigation period, and 77.6% during the late autumn irrigation period lacked irrigation suitability. Two major controlling factors of groundwater chemical characteristics were present in the study area, namely, evaporation and rock weathering, and Na + and Cl - mainly came from the dissolution and cation exchange of salt rocks. Agricultural irrigation and drought were the chief driving factors of groundwater chemical evolution in the Hetao Irrigation Area. The study provides technical support for optimizing agricultural management measures and a theoretical reference for rational utilization of groundwater resources in the Yellow River irrigation area of Inner Mongolia.

To understand the karst groundwater hydrochemical characteristics and ion sources of the Jinan Baotu Spring area, this study focused on the three functional zones as an indirect recharge area, direct recharge area, and discharge area. Through water sample collection and testing, the spatial variability of groundwater chemical characteristics in different functional zones and the formation mechanism were analyzed using hydrochemistry parameter statistics, multivariate statistics, self-organizing map, hydrochemistry graphical analysis, ion ratios, and other methods, guided by the theory of groundwater flow system and combined with regional physical geography and hydrogeological conditions. The results showed that： the groundwater of each functional zone was alkaline as is typical in the dissolution of carbonate minerals. Owing to the different groundwater runoff pathways, the variability of water chemistry parameters in different functional areas was obvious. The groundwater of the discharge area was recharged by both the direct recharge area and the indirect recharge area. The hydrochemistry type changed from HCO 3 -Ca type to HCO 3 ·SO 4 -Ca type through the indirect recharge area to the discharge area. The presence of a small amount of gypsum dissolution within the aquifer generated Ca 2+ and SO 4 2- . The ions in groundwater mainly came from the dissolution and filtration of aquifer rock minerals, and at the same time, they were affected by cation exchange, mineral dissolution equilibrium, and the combined effects of human activities. The groundwater in the Baotu Spring area was greatly influenced by human activities, which to some extent affected the evolution of groundwater hydrochemistry in the spring area.

The control factors of mineralization in the Ljubija ore region are stratigraphic, lithological, magmatogenic, structural-tectonic and hypergenic. The distribution of iron ores in the Ljubija ore region is primarily controlled by the spread of the Olistostrome member of the Carboniferous Javorik flysch formation. Only that member, whether uncovered on the surface or overlain by an Upper flysch member, contains primary siderite-ankerite iron ores. In addition, the distribution of ore bodies is significantly affected by the concentration and location of mineralized limestone and limestonedolomite olistoliths. The seating of carbonate olistolitic bodies in the member is irregular, that is, chaotic. The size, shape, and morphology of these bodies and their boundaries are extremely uneven and diverse, in both primary and tectonic occurrences. Not all olistolitic bodies are mineralized. Those that are can be completely, partially or minimally mineralized. Due to all this, ore bodies and deposits "have no continuity and appear in isolation". Therefore, there is a high exploration risk. These major irregularities are not characteristic of redeposited powdered limonite ores in Plio-Quaternary lacustrine sediments. Cimmerian lateral ruptures were important for the distribution of hydrothermal solutions and today's distribution of ore deposits and occurrences within ore fields and ore nodes. The hypergenic control factor significantly influenced the forming of iron oxide ores. In the Alpine tectogenesis, old systems of faults and joints were renewed and new created. In this respect, the most significant were transverse, open, steep SW-NE ruptures. [ABSTRACT FROM AUTHOR]

Validation of satellite albedo products is an essential step because their quantitative application lie in their ability to record the real state of the earth surface. Upscaling in situ measurements to the corresponding pixel scale is necessary due to the spatial scale mismatch between in situ and satellite measurements. Machine learning-based models have been increasingly used for upscaling because they can yield more reliable results than traditional methods. Nevertheless, the main controlling factors on upscaled results have rarely been discussed. This article explores the control factors that bring uncertainties to the upscaled results based on machine learning models. Three machine learning models, including random forest (RF), $k$ -nearest neighbor (KNN), and Cubist models, were selected to upscale single site in situ-based albedo to the coarse pixel scale. The upscaled results were carefully assessed through comparison with pixel scale albedo reference. The results indicate that the accuracy of upscaled results depends on the machine learning models, the inclusion of key variables related to albedo, the dataset selection of these variables, the amount of training data, and the sensitivity of machine learning models to these factors. Despite the dependence on control factors, the machine learning-based upscaling methods generally have excellent applicability across different spatial scales and over other untrained areas. Therefore, they open the door to generating a time series of globally, spatially continuous distributed reference datasets with sufficient length, consistency, and continuity to adequately fulfill the requirement of a comprehensive validation. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Geological Hazard & Control is the property of China Institute of Geological Environmental Monitoring (CIGEM) Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An iterative structural design process for the conventional, composite wing of a low speed, hybrid Unmanned Aerial Vehicle (UAV) is presented in this paper. The relevant design goals are light weight, strength and stiffness derived from the customer specifications, conceptual design and STANAG-4671 airworthiness standards. To achieve the design goals, a modified Taguchi model was applied in conducting iterative Finite Element Analysis of the loads and stresses on the wing model, using ABAQUS CAE. In this analysis, the pitch of the rib and thicknesses of the spar and skin were applied as control factors in three levels, leading to an L9 orthogonal array. Mass, maximum deflection and Tsai-Hill failure index of the wing structure were measured as responses. The result shows that varying the skin thickness had the most impact on the wing mass, failure index and maximum deflection. The design goal of wing mass-less than 2.5kg, deflection of 10% and Tsai-Hill failure index value-less than 1 were achieved after 9 iterations. [ABSTRACT FROM AUTHOR]

The thermo-mechanical reliability of IMCs (Ni3Sn4, Cu3Sn, Cu6Sn5) solder joints and Sn-3.9Ag-0.6Cu solder joints was investigated systematically in 3D chip stacking structure subjected to an accelerated thermal cyclic loading based on finite element simulation and Taguchi method. Effects of different control factors, including high temperature, low temperature, dwell time of thermal cyclic loading, and different IMCs on the stress-strain response and fatigue life of solder joints were calculated respectively. The results indicate that maximum stress-strain can be found in the second solder joint on the diagonal of IMC solder joints array; for Sn-3.9Ag-0.6Cu solder joints array, the corner solder joints show the obvious maximum stress-strain, these areas are the crack propagated locations. The stress-strain and fatigue life of solder joints is more sensitive to dwell temperature, especially to high temperature; increasing the high temperature, dwell time, or decreasing the low temperature, can reduce the stress-strain and enlarge the fatigue life of solder joints. Finally, the optimal design in the 3D-IC structure has the combination of the Cu6Sn5/Cu3Sn, 373 K high temperature, 233 K low temperature, and 10 min dwell time. The fatigue lives of Sn-3.9Ag-0.6Cu under 218–398 K loading in the 3D assembly based on the creep strain are 347.4 cycles, which is in good agreement with experimental results (380 cycles). [ABSTRACT FROM AUTHOR]

Multi-layer superposition of coal seams and tight sandstone layers is common in Chinese major coal-bearing basins, which possesses huge resource potential. Co-production of coalbed methane (CBM) and tight sandstone gas reservoirs is still in the stage of engineering test in China; the control factors towards the co-production performance remain to be clarified. Based on discussion on the key problems involved in co-production of coal seams and tight sandstone layers, the main control factors governing the co-production performance of CBM and tight sandstone gas are analyzed. Taking well X in Ordos Basin as an example, a co-production numerical model is established. The co-production characteristics of well X are analyzed. The optimization of co-production sequence and hydraulic fracturing parameters of tight sandstone formation is carried out. The results show that the early drainage in coal seams and the reasonable control of bottom-hole flowing pressure are the keys to achieve good development benefits. The co-production is mainly controlled by reservoir permeability, water saturation of sandstone formation, formation-desorption pressure difference of coal seam, reservoir pressure gradient, and surrounding rock properties. Under the optimized co-production sequence of perforating coal seam first and the tight sandstone layer, the tight sandstone layer has a low recovery degree, which may be targeted for later reservoir reconstruction. The recovery degree of tight sandstone layer can be improved by optimizing the hydraulic fracturing parameters such as the fracture half-length and the fracture conductivity. For well X, the fracture half-length and the fracture conductivity are optimized to be 150 m and 300 mD∙m. The findings of this study can be applicable to evaluating the adaptability of geological conditions for multi-layer co-production in coal-bearing basins. Also, the findings can provide theoretical guides for the optimization of production sequence and hydraulic fracturing to improve the co-production benefits. [ABSTRACT FROM AUTHOR]

Magnetic nanomaterials are widely used in biosynthesis, catalysis, as electronic and microwave-absorbing materials, and in environmental treatment because of their high specific surface area, strong magnetism, chemical stability, and good biocompatibility. The chemical coprecipitation method is widely used for the preparation of magnetic nanomaterials due to its simplicity, low cost, and easily-controlled operating conditions. The magnetic nanomaterials prepared by the chemical coprecipitation method are summarized according to the different compositions, including the basic preparation principles, and the factors affecting their morphology, size, and microstructure. The mechanisms of preparing magnetic nanomaterials by chemical precipitation and the process control factors are emphasized. Finally, the preparation of magnetic nanomaterials by chemical coprecipitation is summarized and prospected.

It is of great significance to study the characteristics of wetland water chemistry for the ecological protection and high quality development of wetland. Taking the Wetland of Sanmenxia Reservoir as a typical research area, using the sampling data of 4 times during the impoundment period and drainage period of Sanmenxia Reservoir from 2018 to 2019, the hydrochemical characteristics of the wetland of Sanmenxia Reservoir were analyzed by using hydrochemical methods such as triangle plots and Gibbs plots. The results show that the water in the wetland of Sanmenxia Reservoir is weakly alkaline, and the pH value changes little from Tongguan to Sanmenxia dam during the storage and drainage period, during the discharge period, which is influenced by Swan Lake wetland. During different periods, it shows a decreasing trend in different periods. The dilution effect of Swan Lake wetland in the drainage period is obvious; the DO, ORP, and EC contents are shown to be higher in the impoundment period than that in the drainage period. The ion concentration changes with the water level in the dam impoundment period. The ion concentration in the impoundment period is higher than that in the drainage period. The main cation is Na+, the anions are mainly HCO-3 and the water chemical type is HCO3 -SO4 -Na-Ca. Changes in hydrochemical characteristics of the wetland of Sanmenxia Reservoir are affected by the weathering of silicate rock and the dissolution of evaporative salt rock. In addition, the discharge of the municipal sewage during the impoundment period also has a significant impact on the hydrochemistry of the wetland in the reservoir area. [ABSTRACT FROM AUTHOR]

Featured Application: Landslide susceptibility assessment and other geological disaster assessment issues. Digital elevation models (DEMs) are fundamental data models used for susceptibility assessment of landslides. Due to landscape change and reshaping processes, a DEM can show obvious temporal variation and has a significant influence on assessment results. To explore the impact of DEM temporal variation on hazard susceptibility, the southern area of Sichuan province in China is selected as a study area. Multitemporal DEM data spanning over 17 years are collected and the topographic variation of the landscape in this area is investigated. Multitemporal susceptibility maps of landslides are subsequently generated using the widely accepted logistic regression model (LRM). A positive correlation between the topographic variation and landslide susceptibility that was supported by previous studies is quantitatively verified. The ratio of the number of landslides to the susceptibility level areas (RNA) in which the hazards occur is introduced. The RNA demonstrates a general decrease in the susceptibility level from 2000 to 2009, while the ratio of the decreased level is more than fifteen times greater than that of the ratio of the increased level. The impact of the multitemporal DEM on susceptibility mapping is demonstrated to be significant. As such, susceptibility assessments should use DEM data at the time of study. [ABSTRACT FROM AUTHOR]

Adsorption and desorption of coalbed methane are generally at a dynamic equilibrium state under the undisturbed coal reservoir. However, as the reservoir pressure drops to a certain value during the extraction of coalbed methane, the equilibrium state is destroyed and thus more coalbed methane desorbs and escapes from coal to wellbore. Here the corresponding bottom-hole fluid pressure is called initial gas production pressure (IGPP) in the development practice of coalbed methane wells. This paper, which has taken Changzhi-Anze block in the central-southern part of Qinshui basin as the study object, addresses the distribution characteristic and control factors of IGPP of coalbed methane wells and then explores the key factors affecting IGPP using grey correlation analysis theory. The results indicate that IGPP varies from 1.09 MPa to 6.57 MPa, showing a distribution law with high in the middle and low in the west and east of the study area, which presents a similar distribution characteristic with burial depth, thickness, coal rank, gas content, original reservoir pressure, and in-situ stress. Further, through grey correlation analysis, it concludes that the correlation degrees of control factors affecting IGPP of coalbed methane wells in the descending order are decline rate of working fluid level, water yield before gas production, reservoir pressure, coal thickness, coal rank, minimum horizontal principal stress, burial depth, and gas content. Among these factors, engineering factors, including decline rate of working fluid level and water yield before gas production, present a key controlling effect, because they can determine the smooth migration pathway directly during initial water production. And another key factor, original reservoir pressure also builds strong and positive correlation with IGPP under the interaction of other geology and reservoir factors, revealing the capability of gas desorption and the transmission of pressure drops. [ABSTRACT FROM AUTHOR]

Woo, H.J.; Lee, J,-H.; Choi, J.U., and Kang, J., 2020. Changes in sedimentary processes in macrotidal flats in Garolim Bay, West Coast of Korea. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 722-726. Coconut Creek (Florida), ISSN 0749-0208. Garolim Bay, on the central western coast of Korea, is a semi-enclosed macro-tidal bay with extensive tidal flats that occupy approximately 77% of the bay surface area. The study investigated the sediment characteristics and sedimentation rates to elucidate the spatial and temporal variations in the sedimentary processes in the bay. Surface sediments were sampled to grain-size distributions at 158 stations in July 2002 and July 2014 in the spring tidal cycle. Grain-size distributions were analyzed using standard sieving for the sand fraction and a particle size analyzer for the mud fraction. The geomorphic changes associated with sediment deposition or erosion were investigated along six transect lines on the tidal flats from February 2014 to February 2015 in the ebb tide. The area of sand and muddy sand sediments had extended from the outer to the middle bay in summer 2014, and the percentages of mud were higher in the inner bay compared to the surface sediment distributions in summer 2002. The short-term sedimentation rates from February 2014 to February 2015 showed that erosion was dominant on the tidal flats in the inner bay during spring and on those in the outer bay during winter, with net erosion rates of –1.55 and –55.23 mm/year, respectively. In the middle bay, deposition dominated on the tidal flats, with net deposition rates from 4.85 to 18.94 mm/year. The sediment transport vectors calculated using grain-size parameters for 2002 and 2014 showed that in 2002, sandy sediments were predominantly transported along tidal channels at the bay entrance. However, in winter, sediments from the tidal flats in the outer and middle bay areas are transported to the inner bay by wind-driven waves and tidal currents, resulting in the deposition of sediment on the tidal flats in the inner bay. In summary, the results show that the sediment transport patterns in Garolim Bay changed between 2002 and 2015 due to increased suspended sediment supply and erosion of the tidal flats in the outer bay. Based on these knowledge of sedimentary processes, the major control factors for seasonal variations in sedimentation on the tidal flats in Garolim Bay are tidal currents, wind-driven waves, and sediment inputs. [ABSTRACT FROM AUTHOR]

• Subsurface lateral flow often occurs at 10–40 cm depths along the hillslope. • Wet soil conditions are conducive to triggering hillslope lateral flow. • Variability of infiltration partitioning remains high in the deeper layers. • Dominant factors controlling PWSI are sand (0–10 cm), EL (10–40 cm), and n (40–80 cm). Infiltration is the process of water entering into, and routings through, the subsurface. It has a profound impact on hillslope and catchment runoff. However, because of the hidden and complex subsurface structures, our understanding of rainfall-related infiltration and how it partitions along a topographic gradient remains challenging. In this study, we used two years of field observations of volumetric soil moisture at 25 combinations of topographic positions and soil depths along a steep subtropical forested hillslope. The lateral partition patterns of infiltration and its control factors were investigated based on a new index, percentage of soil water storage increment at each site to all hillslope sites during a rainfall event (PWSI). Our results showed that the active soil layer involved in hillslope lateral flow was distributed within the depths of 10–40 cm. In deep soil depths (i.e., 40–80 cm), lateral flow was more evident under wet initial moisture conditions than under dry initial moisture conditions, whereas rainfall characteristics had a relatively weak effect on it. Unexpectedly, we found the variability of infiltration partitioning remained high in the deeper soil layers. Among the soil properties, sand, bulk density, n , K S , and SOM were conducive to infiltration, whereas clay had the opposite effect. The dominant factors controlling the lateral partition patterns of infiltration across soil depths were sand in the depths of 0–10 cm, topographic gradient in depths of 10–40 cm, and n (parameter of soil retention curve) in the depths of 40–80 cm. Findings of this study reveal the infiltration partitioning indices were useful to quantitatively describe the distribution patterns of infiltration after rainfall events at the hillslope, and provide new insights into the detection of hillslope lateral flow, which is valuable for understanding subsurface hydrological processes and improving water resource management in humid mountain ecosystems. [ABSTRACT FROM AUTHOR]

The changes in the condition of markets of non-banking financial services under the influence of state regulation instruments are investigated. As a result of using diagnostic tools for assessing the condition of markets of non-banking financial services based on forecasting scenarios of changes in the condition of the credit services market, the market of private pension provision and the insurance market, the influence of the Regulator’s activities and external factors has been evaluated and forecasted. There made a conclusion about the necessity of using the developed diagnostic tools in determining the priority of the influence of the Regulator’s activities with the aim of leveling the negative influence of external factors on the condition of markets of non-banking financial services.

Shallow groundwater is the main source of water for living and industrial and agricultural production in Anqing City, which is an important basic guarantee to maintain the sustainable development of the social economy and regional ecological environment. In order to further study the water chemical characteristics and controlling factors of shallow groundwater in Anqing City, 196 groups of shallow groundwater samples were collected. A Piper diagram graph, Gibbs chart, ion ratio, and mathematical statistics were comprehensively used to study the water chemical characteristics and controlling factors of groundwater in Anqing City, and the contribution of different sources to the water chemical components of groundwater was quantitatively evaluated. The results showed that the shallow groundwater in Anqing City was weakly alkaline, with pH values ranging from 5.84 to 8.38, with an average value of 7.21. The TDS ranged from 47 to 1 620 mg·L -1 , with an average of 324.21 mg·L -1 . HCO 3 - and Ca 2+ were the main anions, and the water chemical type was HCO 3 -Ca type. The chemical components of groundwater were affected by rock weathering leaching, cation alternating adsorption, mineral dissolution and precipitation, and human activities. Ca 2+ , Mg 2+ , and HCO 3 - were mainly derived from the weathering dissolution of carbonate and silicate; Na + , Cl - , and SO 4 2- were affected by industrial activities and domestic sewage discharge; and K + and NO 3 - were affected by agricultural activities. The APCS-MLR receptor model analysis further revealed that the chemical components of groundwater were mainly geological factors, industrial factors, agricultural factors, and unknown sources, and their contribution rates were 45.35%, 14.19%, 25.38%, and 15.08%, respectively. Geological factors were important sources of hydrochemical components of shallow groundwater, and human activities aggravated the evolution of groundwater hydrochemistry.

In order to better support the construction of the capital water conservation functional area and ecological environment support area， research on the chemical characteristics of groundwater and its formation mechanism in the dry period in the Zhangjiakou area can provide a great reference for the rational development and utilization of groundwater resources. A total of 41 groups of groundwater samples were collected， and the hydrochemical types， composition characteristics， and control factors of groundwater in the study area were analyzed by using the combined method of descriptive statistical analysis， Piper triplot， correlation analysis， Gibbs plot， and ion ratio. The results showed that the groundwater in the study area was weakly alkaline， with the total hardness and ρ （TDS） ranging from 105.00 mg·L -1 to 1 433.00 mg·L -1 and 137.00 mg·L -1 to 2 286.00 mg·L -1 ， respectively. The total hardness and TDS mass concentrations of groundwater in the Bashang area were higher than those in the Baxia area. HCO 3 - and Na + were the main dominant anions and cations in the groundwater in the study area. The highest overstandard rate of the main components in groundwater was that of total hardness （36.59%）. The overstandard rate and maximum excess multiple of each component in groundwater in the Bashang area were greater than those in the Baxia area. HCO 3 -Ca·Mg·Na was the main type of groundwater hydrochemistry in the study area， and there was little difference between the Bashang area and the Baxia area. SO 4 2- ， Cl - ， HCO 3 - ， Na + ， and Mg 2+ contributed the most to TDS. The chemical characteristics of groundwater were affected by weathering and filtration of rock minerals such as salt rock， albite， and dolomite； cation exchange； and human activities. Evaporative crystallization and atmospheric precipitation contributed to a small part of the main ion source of groundwater in the area. The effect of human activities on groundwater in the Bashang area was greater than that in the Baxia area， and NO 3 - mainly originated from agricultural activities.

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs; study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niutitang Formation (Fm), Southern China. In this study, core observation and lithology study were conducted along with X‐ray diffraction (XRD) and electronic scanning microscopy (SEM) examinations and liquid nitrogen (N2) adsorption/desorption and CH4 isothermal adsorption experiments for several exploration wells in northwestern Hunan Province, China. The results show that one or two intervals with high‐quality source rocks (TOC>2 wt%) were deposited in the deep‐shelf facies. The source rocks, which were mainly composed of carbonaceous shales and siliceous shales, had high quartz contents (>40 wt%) and low clay mineral (<30 wt%, mainly illites) and carbonate mineral (<20 wt%) contents. The SEM observations and liquid nitrogen (N2) adsorption/desorption experiments showed that the shale is tight, and nanoscale pores and microscale fractures are well developed. BJH volume (VBJH) of shale ranged from 2.144×10–3 to 20.07×10–3 cm3/g, with an average of 11.752×10–3 cm3/g. Pores mainly consisted of opened and interconnected mesopores (2–50 nm in diameter) or macropores (>50 nm in diameter). The shale reservoir has strong adsorption capacity for CH4. The Langmuir volume (VL) varied from 1.63 to 7.39 cm3/g, with an average of 3.95 cm3/g. The characteristics of shale reservoir are controlled by several factors: (1) A deep muddy continental shelf is the most favorable environment for the development of shale reservoirs, which is controlled by the development of basic materials. (2) The storage capacity of the shale reservoir is positively related to the TOC contents and plastic minerals and negatively related to cement minerals. (3) High maturity or overmaturity leads to the growth of organic pores and microfractures, thereby improving the reservoir storage capacity. It can be deduced that the high percentage of residual gas in Niutitang Fm results from the strong reservoir storage capacity of adsorbed gas. Two layers of sweet spots with strong storage capacity of free gas, and they are characterized by the relatively high TOC contents ranging from 4 wt% to 8 wt%. [ABSTRACT FROM AUTHOR]

Abstract Mega-blowouts are very large-scale deflationary landforms, formed by wind erosion. They are abundant in the Gonghe basin, northeast margin of the Qinghai-Tibet Plateau (QTP) and little is known about the evolution, dynamics or controls on the mega-blowout development. Here we report on mega-blowouts' morphodynamic expansion rates based on 4 years of monitoring. Also presented is a remotely sensed longer-term (48 years) morphologic change record which is used to understand the initiation, growth and evolution of mega-blowouts in alpine grasslands. Links between the morphodynamics and blowout-controlling factors are analysed. The expansion rates of the monitored blowouts vary according to blowout area, with different parts of the blowouts expanding at different rates. Generally longitudinal (downwind) mega-blowout expansion is greatest, with upwind headwall expansion via collapse being particularly significant. The growth of depositional lobes downwind of mega-blowouts tends to be faster than growth of the deflation basins. Merging of adjacent blowouts is one of the key mechanisms for mega-blowout development and extension. Sediment characteristics, wind erosion, water erosion, and freeze-thaw processes also all play a part in mega-blowout initiation and expansion. However, the relative roles that these factors play may differ according to a blowout's evolutionary stage. Due to an almost unlimited depth of sand, very low water table, and short grass vegetation cover, evolution into parabolic dunes is limited. A large proportion of sand patches and small blowouts around the mega-blowouts are still developing in the Gonghe basin proving that land degradation is still ongoing. Future work will focus on the feedback mechanisms between the blowout morphodynamics, climate change and anthropogenic impacts. [ABSTRACT FROM AUTHOR]

Microplastics are emerging pollutants that can adsorb heavy metals and threaten human health through food chain. Recently, there has been increasing interest in understanding the adsorption behavior of heavy metals by microplastics in farmland soil. In particular, arsenic (As), as a carcinogen, has the potential to be adsorbed by soil microplastics. However, the mechanisms and controlling factors of As adsorption by microplastics in farmland soil under natural conditions are still unknown. Here, microplastics and As were respectively added to farmland soils with different physicochemical properties from twelve provinces of China for adsorption experiment. We performed surface analysis of microplastics, quantified As accumulation through quasi-first-order kinetic equation and developed regression models to screen the factors controlling As adsorption. The results showed that the adsorption of As by soil microplastics was a chemical process accompanied by the loss of electrons from oxygen-containing functional groups. Soil cation exchange capacity (CEC) was the main factor controlling the adsorption rate, while soil organic matter (SOM), total nitrogen (TN) and CEC mainly influenced the equilibrium adsorption capacity. This is the first report on microplastic-As adsorption in natural soil, which allows deeper insights into risk assessment, prediction and control of microplastic-As pollution in agricultural soil. [Display omitted] • As was captured by the oxygen on the soil microplastic surface after adsorption. • The rate of As adsorption by soil microplastics was mainly controlled by CEC. • The equilibrium adsorption capacity of As was affected by CEC, TN and SOM. [ABSTRACT FROM AUTHOR]

Large landslides (volume greater than or equal to 106 m3) usually have disastrous consequences and clearly influence the evolution of the local landscape. In this study, a detailed investigation of large landslides, across 20 towns over an area of 5000 km2, was carried out on the northeastern margin of the Bayan Har Block, at the eastern margin of the Tibetan Plateau, China. The results show that there are 129 large landslides in this area. Among them, 79 landslides have volumes within 106–107 m3, 52 landslides have volumes within 107–108 m3 and 2 landslides have volumes larger than 108 m3. Most of these landslides are distributed along rivers, and more than 32% are densely concentrated in three small regions. The landslides mainly occur in high slopes and exhibit obvious sturzstrom characteristics. Analysis of the factors controlling landslide occurrence shows that elevation, slope angle, slope aspect, lithology, faults and rivers (valley) clearly influence landslide occurrence, while rainfall has no obvious influence. Earthquakes are considered an important trigger of and contributor to landslide occurrence.

Digital elevation models (DEMs) are fundamental data models used for susceptibility assessment of landslides. Due to landscape change and reshaping processes, a DEM can show obvious temporal variation and has a significant influence on assessment results. To explore the impact of DEM temporal variation on hazard susceptibility, the southern area of Sichuan province in China is selected as a study area. Multitemporal DEM data spanning over 17 years are collected and the topographic variation of the landscape in this area is investigated. Multitemporal susceptibility maps of landslides are subsequently generated using the widely accepted logistic regression model (LRM). A positive correlation between the topographic variation and landslide susceptibility that was supported by previous studies is quantitatively verified. The ratio of the number of landslides to the susceptibility level areas (RNA) in which the hazards occur is introduced. The RNA demonstrates a general decrease in the susceptibility level from 2000 to 2009, while the ratio of the decreased level is more than fifteen times greater than that of the ratio of the increased level. The impact of the multitemporal DEM on susceptibility mapping is demonstrated to be significant. As such, susceptibility assessments should use DEM data at the time of study.

Taking the Tugeligaole sub-basin of the Jilantai Salt Lake Basin in Inner Mongolia as the typical study area, the groundwater samples of 22 points were collected, and their main characteristic indexes were tested during the wet season and the dry season separately in 2021. Mathematical statistics, Piper triangular diagrams, a Gibbs plot, ionic relations, and factor analysis were used to analyze and discuss the hydrochemical characteristics and formation mechanism of groundwater in different periods. Based on the evaluation of the groundwater quality using the water quality index(WQI) method, the potential risks of groundwater Cr 6+ and F - were evaluated using the health risk evaluation model. The results showed that the groundwater was overall weakly alkaline; the dominant anions and cations during the different periods were Cl - and Na + , and the water chemistry type was mainly Cl - -Na + ; the groundwater quality was generally good, and the difference in water quality between the wet season and the dry season was not significant; adults and children had higher carcinogenic health risks in the dry season than that in the wet season, and the health risks of children were significantly higher than those in adults. The maximum carcinogenic health risk of drinking water exposure to Cr 6+ in adults and children was higher than the maximum acceptable risk level(5×10 -5 ). The chemical evolution of groundwater was mainly affected by evaporative concentration, evaporative salt rock dissolution, and cation exchange, and the main control factors were evaporative concentration(contribution rate of 54.19%), native geological environment factors(contribution rate of 12.99%), and carbonate rock dissolution(contribution rate of 11.66%). The study results have significance to some degree to the sustainable exploitation and utilization of groundwater resources and environmental protection of the salt lake basin.

Hydrogen sulfide provides an abundance anomaly in many coal mines (districts) in southeastern margin of Junggar basin in China. There are three sets of source rocks in this area, where the coal bearing strata mainly involve low metamorphic bituminous coals of the Xishan formation and the Badaowan formation with less than 45°C geotemperature, which is beneficial to the propagation of Sulfate-Reducing Bacteria. The average Sulfate-Reducing Bacteria value of samples is 791 grams / sample. Along with the runoff direction, the salinity and pH value of groundwater gradually increase. And the hydrochemical types of groundwater are evolved into HCO3-SO4-Cl-Na by HCO3-Ca-Na and HCO3-SO4-Na-Ca, with the main components of NaHCO3. In a reducing environment and with the hydrocarbon abundance, the bacterial sulfate reduction is prone to occur and H2S is likely to form. Meanwhile, the better pore types of the reservoir are mainly the intergranular pore and intragranular dissolved pore. The average porosity of each coal seam is about 8.5% / porosity values are medium, the average permeability is (5.36x10-3~11.6x10-3) um2 / permeability values are low. The top and bottom slates of coal seam are mainly composed of fine clastic rock and low permeability barrier with the characteristics of good sealing ability. All of this provides a wide space for the reservoir of H2S, under the action of groove type subsidence structure, uplift type relief structures and the hydrodynamic control of methane. Two types of H2S accumulation mode of northward monoclinic and imbricated fan-shaped ware formed in specific geological condition. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The loess caves developed on Chinese loess plateau are not only a typical phenomenon of soil and water loss, but also a special kind of geological hazard. Many loess dilapidations, collapses and medium to small-sized landslides are related to the loess caves. To understand the characteristics and the geo-disasters induced by loess caves, the loess caves developed on Chinese loess plateau were rigorously investigated. Based on a long-term field surveys on about 800 fixed points in Gansu, Ningxia and northern Shaanxi, the classifications and characterization of loess caves in Chinese loess plateau are discussed in detail. Moreover, the regionally developmental regularity hierarchical development regularity of loess cave and its characteristics are studied in this paper, which show that the density of loess caves on the northwestern loess plateau is higher than that in the southeastern loess plateau than that in the southeast in China. And the main control factors affecting the development of loess caves are analyzed. Interestingly, the development of the caves is related to the loess layer, land characteristics, geologic structure (including the joints and the fracture system), micro topography, hydro-geological factors and climatic conditions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to investigate the specificity of the openness of the system of social morality to influence of the various phenomena of natural and social being. To achieve this goal it is necessary to identify the control factors of the system of social morality and describe characteristics of their interaction with the system. Methodology. The research is based on the use of synergetic methodology, according to which social morality is treated as an open complex self-organizing system. The openness and non-linearity are the main methodological principles of synergetics, which were used in the study. Scientific novelty of the research lies in the fact, that the idea of openness of the system of social morality to influence of the various phenomena of natural and social being and, above all, those that can be called «control factors» has been comprehensively investigated for the first time. It is noted nonlinear connection between system of social morality and its control parameters, the existence of circular causality between them, the difference in the intensity of the influence of different control factors on morality. Conclusions. Openness of the system of social morality provides, that external factors have an impact on it. Among them there are factors which impact is most relevant. We call them the control factors of the system of social morality. They can be divided into two main groups: the first are those, that have a social origin, and the second – biological. Macro level of morality (moral consciousness) is a new quality in comparison with the control factors. It is not their linear extension, because though it is formed by their influence, but the immediate cause of its appearance is self-organization mechanisms. Control factors are differ by the intensity of their impact on the system of social morality. Among them are those, which can be considered as fundamental, because structures, which are formed under their influence, are the basis of morality. The influence of others is usually lower, although at certain periods of system development it may increase or decrease. Interaction between the system of social morality and its controlling factors is characterized by circular causality: controlling factors affect morality and, in turn, they are subject to its influence.

Geometric parameters are useful for characterizing earthquake-triggered landslides. This paper presents a detailed statistical analysis on this issue using the landslide inventory of the 2013, Minxian, China Mw 5.9 earthquake. Based on GIS software and a 5-m resolution DEM, geometric parameters of 635 coseismic landslides (with areas larger than 500 m) were obtained, including height, length, width, reach angle (arc tangent of the height-length ratio), and aspect ratio (length-width ratio). The fitting relationship of height and length from these data is H = 0.6164 L + 0.4589, with an average reach angle of 31.65°. The landslide aspect ratios concentrate in the range of 1.4∼2.6, with an average of 2.11. According to the plane geometric shapes and aspect ratios, the landslides are classified into four categories: transverse landslide (LA1, L/ W ≤ 0.8), isometric landslide (LA2, 0.8 < L/ W ≤ 1.2), longitudinal landslide (LA3, 1.2 < L/ W ≤ 3), and elongated landslide (LA4, L/ W > 3). Statistics of these four types of landslides versus ten classified control factors (elevation, slope angle, slope aspect, curvature, slope position, distance to drainages, lithology, seismic intensity, peak ground acceleration, and distance to seismogenic fault) are used to examine their possible correlations and the landslide-prone areas, which would be helpful to the landslide disaster mitigation in the affected area. [ABSTRACT FROM AUTHOR]

Recently, the abundant occurrence of galls of Contarinia petioli (Kieffer) was noted on Populus tremula in the Brno region and elsewhere in southern Moravia. The bionomics and cecidogenesis of the gall midge was studied on 5 to 15-year-old aspens in Forest District Bílovice nad Svitavou, Training Fo­rest Enterprise Masaryk Forest in Křtiny in 2007 and 2008. Imagoes fly there at the end of April and at the beginning of May. Females lay eggs in several partial clutches at 1 to 6(10) pieces. About 91% newly hatched larvae settle on petioles of unfolding leaves, about 8% on the bark of terminal parts of shoots and about 1% on leaf blades. By means of sucking the larvae of the 1st and 2nd instars galls are crea­ted in the 1st half of May. Larvae of the 3rd instar occur in galls from the 20th May when galls are grown-up. Larvae abandon the galls in the 1st decade of June through an oval hole 0.6 × 0.4 mm in diameter. Galls are on average 6 mm long, 5.4 mm wide and 5.1 mm high. If they are localized within a short distance of each other then often create formations up to 17 × 11 × 9 mm in size. There are 1 to 6(10) chambers in galls and in each of them, only one larva develops. The paper deals in detail with the differentiation of galls including chambers as well as natural enemies of the gall midge. Torymus quercinus Boh., T. cultrans Graham & Gijswijt (Torymidae) and Tetrastichus sp. (Eulophidae) rank among natural enemies of larvae in galls.1

• Meadow tends to retain infiltration at the surface soil due to mattic epipedon. • Hillslope sites affect infiltration partitioning by influencing soil properties. • The quantitative indices improve our understanding of infiltration partitioning. Infiltration process controls how rainfall is stored in soil and subsequently used by plants, thus, plays a critical role in eco-hydrological processes. However, the vertical pattern of infiltration partitioning within a soil profile and the factors that control it remain poorly understood, especially in data-scarce mountainous areas. Based on a large-scale long-term soil moisture (SM) network in the Qilian Mountains, Northwest China, we explored infiltration partitioning and its control factors using a new metric, percentage of soil water storage increment in each layer to the soil profile during a rainfall infiltration event (PSTI). We found that both vegetations with deep roots and wet SM conditions facilitated infiltration into the deeper soil, although meadow favored infiltration within the surface layer. Hillslope stations showed a higher degree of infiltration partitioning in subsurface layers than the flatland stations due to the influence of topography on soil properties. Meanwhile, the increasing slope gradient will reduce the partition of infiltration at the subsurface layers. Among the soil properties, sand content, soil organic carbon, α (parameter of soil retention curve), and soil saturated hydraulic conductivity promoted infiltration into greater depth, while clay content and bulk density had the opposite effect. The major factors controlling the pattern of infiltration partitioning were n (parameter of soil retention curve) for 0–10 cm depth, α for 10–20 cm and 20–30 cm depths, and SM for PSTI below 30 cm. This quantitative analysis method for the infiltration partitioning improves our understanding of infiltration regimes, and supports water resources management in dryland mountains. [ABSTRACT FROM AUTHOR]

Groundwater is one of the major sources of water supply, especially in the western arid regions. However, with the deepening of the western development strategy, industrialization and urbanization have increased groundwater resource demands in Xining City. Overexploitation and utilization have led to a series of changes in the groundwater environment. Identifying the chemical evolution characteristics and formation mechanism of groundwater is crucial for preventing its deterioration and ensuring sustainable use. By combining hydrochemistry and multivariate statistical techniques, the chemical characteristics of groundwater in Xining City were analyzed, and the formation mechanism of groundwater and the influence of different factors were discussed. The results showed that there were as many as 36 chemical types of shallow groundwater in Xining City, mainly HCO 3 -Ca(Mg) (60.00%) and HCO 3 ·SO 4 -Ca(Mg) (11.81%). There were 5-6 types of groundwater chemical types in bare land, grassland, and woodland. Groundwater chemical types in construction land and cultivated land were more complex, up to 21 types, indicating that they were strongly affected by human activities. The chemical evolution process of groundwater in the study area was mainly affected by rock weathering and leaching, evaporative crystallization, and cation exchange. The main controlling factors were water-rock interaction (contribution rate 27.56%) and industrial wastewater discharge (contribution rate 16.16%), acid-base environment (contribution rate 16.00%), excessive application of chemical fertilizers and pesticides (contribution rate 13.11%), and domestic sewage (contribution rate 8.82%). On account of the chemical characteristics of groundwater in Xining City and the influence of human activities, the management and control suggestions on the development and utilization of groundwater resources were put forward.

Despite the benefits arising from incorporating crop residue in the soil, some farmers decide to burn or sell it. The objective of the work described in this paper was to quantify the adoption of crop residue incorporation by Italian farmers, and to identify the barriers and drivers that they perceive towards this agricultural management practice. We applied a behavioural approach, based on the theory of planned behaviour. In agriculture, this theory can be used to study individual farmer beliefs to understand the intention to adopt agricultural management practices. Based on preliminary semi-structured interviews with 24 farmers, we have prepared and disseminated a structured questionnaire in dairy farms in the plain of northern Italy, in arable farms in the plain of northern, central, and southern Italy, and in arable farms in the hill of central and southern Italy. The questionnaire contained questions to reveal subjective beliefs of the farmers on the outcomes of incorporating crop residue, and on the referents and control factors that might influence adoption. We have received 315 filled questionnaires from 16 regions and 54 provinces. The survey has identified major drivers and barriers towards the incorporation of crop residue in the soil. The main drivers were the expected improvement of soil quality (higher soil organic matter, improved structure and fertility), the expected increase of grain protein concentration in the following wheat crop, the availability of adequate machinery, the prohibition of burning crop residue, and the knowledge that incorporation is important (which emphasizes the importance of an effective advisory service). The main barriers were the costs of incorporation, the need to increase the use of nitrogen fertiliser when straw is incorporated, and the problems to sow the following crop in the presence of residue. While on the basis of the preliminary interviews we expected that the possibility to sell the straw and the slow residue decomposition in the soil could be barriers against residue incorporation in the soil, questionnaire results did not confirm this expectation. The survey did not indicate that farmers are particularly worried about crop residue as potential sources of weeds, pests and diseases. Even if the methodology applied did not identify any of the referents as important barriers or drivers, there were important differences with respect to the perceived opinion of the social environment between adopters and non-adopters. This emphasizes the importance of an encouraging social environment for the propagation of good practices.

Evolutionary trajectories and related control factors of the Fortore River (southern Italy) are analyzed over a 150-year period as to assess channel modifications. A multitemporal GIS analysis of topographic maps and aerial photographs together with topographic and geomorphological field surveys were performed. Attention was focused on the impact caused by human disturbance, above all the presence of the Occhito dam at only 40 km upstream of the Fortore mouth (central Adriatic coast). Results show that channel adjustments occurred in three distinct phases and were primarily driven by human disturbance that diversely affected reaches located upstream and downstream of the dam. From the last decades of the nineteenth century to the 1950s (phase 1), channel widening prevailed along upstream reaches whilst narrowing along downstream reaches. Major channel adjustments occurred from the 1950s until the end of the 1990s (phase 2), especially channel narrowing of up to 81% in upstream reaches and 98% in downstream reaches. Narrowing was accompanied by channel-bed lowering of 1 to 5 m and by pattern changes in prevalence from multithread to largely prevailing single-thread channel configurations. In-channel mining, channel works, and hydraulic interventions are considered key driving factors of observed channel adjustments. The closure of the Occhito dam in 1966 had significant and permanent effects on downstream reaches through overall discharge regulation and permanent sediment trapping as also proved by the progressive retreat of the Fortore river mouth area. From 2000 to 2015 (phase 3), a substantial trend inversion was observed with overall channel widening and partial aggradation of upstream reaches and total stabilization of downstream reaches. As highlighted by an integrated multitemporal analysis of recent channel changes and flood events, the latter have played an important role in channel recovery of upstream reaches. Comparison between the Fortore River and other rivers in southern Italy has allowed us to ascertain that the reconstructed evolutionary trajectories are quite similar and that control factors are essentially the same. In particular, it confirms the role of major hydraulic structures as to the amount of channel adjustments of downstream reaches and the ensuing scarce to nil potential to channel recovery of regulated reaches. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the popularity of mobile smart devices and functional diversification, the infection ways of mobile smartphones worm also become diverse. In mobile networks, mobile devices are suffering from the threat of worms all the time. Once the worm outbreaks, it will bring huge losses to mobile phone users and mobile network operators. Researches on mobile worm propagation model allow us to control and detect potential worm threat, according to the characteristics of worm's outbreak. In the paper, we put forward a worm propagation model based on the mobile network environment. After analyzing the model, we then give the simulation for controlling factors affecting worm propagation. This model allows us to have a certain understanding for the spread on the size and speed of the mobile worm and provide effective methods to control the spread of the mobile worm. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Bottom-up and top-down control of phytoplankton is one of the most important hypothesis that explains and predicts the structure of aquatic community. Our aim was to elucidate whether predation and resource limitation can control phytoplankton composition and abundance in a subtropical shallow lake with groundwater connection to the river system. During 12 months, the lake was sampled at three points. Physico-chemical parameters, phytoplankton and zooplankton were sampled fortnightly, whereas fish were sampled every 3 months. The results showed that Euglenophyta dominated the total biovolume, followed by Dinophyta and Cryptophyta. As for the species composition, Chlorophyta was the dominant group (80 species recorded), followed by phylum Cyanobacteria (26 species recorded). Redundancy analysis (RDA) indicated that temperature and nitrate + nitrite concentration mainly explained biovolume changes, with zooplankton predation not having any measurable effect on phytoplankton during the high-water (HW) period. During low-water (LW) period top-down by fish was more important. At higher taxonomic resolution (species biovolume), phosphorus was another controlling factor. We concluded that phytoplankton in this lake is mainly regulated by hydrological changes as a macrofactor that affects nutrient availability and other environmental conditions. Even though bottom-up top-down forces do not have a central effect, we found evidence of positive nutrient influences at the HW period and fish effect at the LW period. Top down-bottom up is one of the major hypotheses that explain aquatic communities' structure. In this study we aim to prove it in a subtropical shallow lake using phytoplankton as study object. We realised that phytoplankton is mainly regulated by hydrological changes that affect nutrient availability and predation. Evidence suggest that top down-bottom up model is not completely valid for shallow subtropical lakes where new models should be fashioned. [ABSTRACT FROM AUTHOR]

Despite the benefits arising from incorporating crop residue in the soil, some farmers decide to burn or sell it. The objective of the work described in this paper was to quantify the adoption of crop residue incorporation by Italian farmers, and to identify the barriers and drivers that they perceive towards this agricultural management practice. We applied a behavioural approach, based on the theory of planned behaviour. In agriculture, this theory can be used to study individual farmer beliefs to understand the intention to adopt agricultural management practices. Based on preliminary semi-structured interviews with 24 farmers, we have prepared and disseminated a structured questionnaire in dairy farms in the plain of northern Italy, in arable farms in the plain of northern, central, and southern Italy, and in arable farms in the hill of central and southern Italy. The questionnaire contained questions to reveal subjective beliefs of the farmers on the outcomes of incorporating crop residue, and on the referents and control factors that might influence adoption. We have received 315 filled questionnaires from 16 regions and 54 provinces. The survey has identified major drivers and barriers towards the incorporation of crop residue in the soil. The main drivers were the expected improvement of soil quality (higher soil organic matter, improved structure and fertility), the expected increase of grain protein concentration in the following wheat crop, the availability of adequate machinery, the prohibition of burning crop residue, and the knowledge that incorporation is important (which emphasizes the importance of an effective advisory service). The main barriers were the costs of incorporation, the need to increase the use of nitrogen fertiliser when straw is incorporated, and the problems to sow the following crop in the presence of residue. While on the basis of the preliminary interviews we expected that the possibility to sell the straw and the slow residue decomposition in the soil could be barriers against residue incorporation in the soil, questionnaire results did not confirm this expectation. The survey did not indicate that farmers are particularly worried about crop residue as potential sources of weeds, pests and diseases. Even if the methodology applied did not identify any of the referents as important barriers or drivers, there were important differences with respect to the perceived opinion of the social environment between adopters and non-adopters. This emphasizes the importance of an encouraging social environment for the propagation of good practices. [ABSTRACT FROM AUTHOR]