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Using detailed data on company visits by Chinese mutual funds, we provide direct evidence of mutual fund information acquisition activities and the consequent informational advantages mutual funds establish in local firms. Mutual funds are more likely to visit local and nearby firms both in and outside of their portfolios, but the ease of travel between fund and firm locations can substantially alleviate geographic distance constraints. Company visits by mutual funds are strongly associated with both fund trading activities and fund trading performance. Our results show that geographic constraints and costly information acquisition amplify information asymmetry in financial markets. [ABSTRACT FROM AUTHOR]

The bioenergy crop switchgrass (Panicum virgatum L.) has been recognized as friendly to the soil of cultivated land depending on the previous land use types and management practices. However, the effects of switchgrass establishment on soil properties at a broader depth when it is harvested annually without any fertilization in northern China largely remain unknown. To explore the impacts of unfertilized switchgrass on soil physical and chemical properties, 0–100 cm soil samples were collected from 7-year cropland-to-switchgrass conversion and the bare land (control). The results showed that switchgrass establishment increased soil total and capillary porosity, CFU numbers of the microbial communities (fungi, bacteria, and actinomycetes), contents of microbial biomass (carbon, nitrogen, and phosphorus), and water-soluble organic carbon, and decreased soil bulk density, mostly at 0–60 cm depths, compared to the control values. Notably, the annual harvest of switchgrass insignificantly increased soil total and available nitrogen contents and slightly reduced available phosphorus and potassium contents. In conclusion, long-term cropland conversion to unfertilized switchgrass could ameliorate soil properties and does not cause soil depletion. The output of this study could inspire governments and farmers to make large-scale use of switchgrass in the ecological restoration of abandoned cropland in north China. [ABSTRACT FROM AUTHOR]

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Atrazine is frequently detected in surface runoff and poses a potential threat to the environment. Grass hedges may minimize runoff loss of atrazine from crop fields. Therefore, the effectiveness of two grass hedges (Melilotus albus and Pennisetum alopecuroides) in controlling atrazine runoff was investigated using simulated rainfall on lands at different slope gradients (15 and 20%) in northern China. Results showed that a storm (40 mm in 1 h), occurring 4 h after atrazine application, caused a loss of 3% of the applied amount. Atrazine loss under 20% slope was significantly greater than that under 15% slope in control plots. Atrazine exports associated with the water fraction accounted for the majority of total loss. Pennisetum hedges were more efficient in controlling atrazine loss with runoff compared to Melilotus hedges. No significant difference in the capacity of grass hedges to reduce atrazine exports was observed between 15 and 20% slopes. These findings suggest grass hedges are effective in minimizing atrazine runoff in northern China, and Pennisetum hedges should be preferentially used on sloping croplands in similar climatic regions. [ABSTRACT FROM AUTHOR]

Pesticide loss triggered by runoff is one of the most important sources of non-point pollution. The effects of grass hedges ( Melilotus albus and Pennisetum alopecuroides ) on atrazine runoff under different rain intensities and slope gradients were evaluated. The plot-scale experiments were carried out on a maize ( Zea mays ) field on slopes with 15% and 20% gradients using simulated rainfall (rain intensity of 30 and 45 mm h −1 ). Atrazine residues were investigated in runoff water and soil taken from three depths (0–5, 5–10, and 10–15 cm) in the middle and base of the slope after runoff events. Total atrazine loss in runoff water ranged from 2.3% to 4.9% of that applied from plots without grass hedges. Grass hedges decreased atrazine loss by 37%-76% and surface runoff by 27%-72%, and Pennisetum showed better efficacy than Melilotus, especially under higher rain intensity. Atrazine loss showed a significant positive linear correlation with surface runoff volume. Grass hedges had a more significant effect on atrazine loss than rain intensity and slope gradient. But they functioned less effectively if used under intense rain or/and steep slope conditions. Atrazine residues remained in the surface 15 cm soil were higher for the plots with grass hedges than the control plots. These results suggest that grass hedges not only significantly reduced atrazine loss by reducing the surface runoff, but also reduced the amount of atrazine leaching to deeper soil layer. P. alopecuroides was a suitable grass-hedge species for controlling atrazine losses in northern China and similar regions. Other management practices or control measures should be integrated with grass hedges in strongly sloping cropland in high-rainfall areas to maintain pesticide losses at an acceptable level. [ABSTRACT FROM AUTHOR]

The establishment, reproduction, dispersal, and distribution of alien plants are affected by various factors during the transition from being newly introduced in a habitat to being invasive. In the agro-pastoral ecotone of northern China, comprising farmlands and natural grasslands, the biological characteristics of alien plant species were the key intrinsic factors (propagation characteristics and competitive ability), followed by such extrinsic factors as human interference and environmental heterogeneity. Among biological characteristics, the life form may be an important and useful indicator of the invasive ability of a species, and the risk of invasion is greater from alien species that are poisonous, inedible, and have traits that facilitate wide dispersal. Farmlands may serve as initial shelters for alien species, from which they spread into neighbouring habitats, whereas natural grassland may act as a barrier to plant invasions. Management practices detrimental to grasslands, including overgrazing, reclamation, and road construction, often facilitate the invasions; therefore, counter measures such as reseeding and a ban on grazing need special attention. Environmental factors including precipitation, nutrients, prevailing winds, fires, and topography may be other factors that promote or block the process of invasion. In studying ways of preventing or controlling such invasions, alien plants with short life cycle, prolific seed production, and strong competitiveness, deserve particular attention and so do human activities that may damage the environment and fragile habitats. [ABSTRACT FROM AUTHOR]

This paper presents a synthetic U-Pb and Hf isotopic study of zircons and a whole-rock geochemical study on diabase swarms that were emplaced into the Proterozoic formations in the Xuzhou-Huaibei area, the southeast margin of North China Craton. Zircons from the diabase dykes display weak oscillatory zoning in the cathodoluminescence (CL) images and show high Th/U ratios (0.91-6.90), both of which are typical of a magmatic origin. The SHRIMP and Q-ICP-MS U-Pb zircon dating results indicate that the diabase swarms were emplaced at ca. 890 Ma. Hf isotopic analysis on these zircons gives ɛ( t) values ranging from 2.26 to 14.74 and Hf model age t and t ranging from 843 to 1321 Ma and from 808 to 1779 Ma, respectively. Geochemically, the diabase swarms are characterized by a relative enrichment in LREE and LILE (Rb, Ba and La), a comparative enrichment in Cr and Ni, but a slight depletement in HFSE (Th, Nb, Ta, Zr and Hf). They are plotted in the within-plate tholeiite series on the tectonic discrimination diagrams. Taken together, these geochemical and isotopic data suggest that the primary magmas to form the diabase dykes in the Xuzhou-Huaibei area could have been derived from a transitional mantle in the Mesoproterozoic, and were most probably emplaced under a continental margin extensional setting at ca. 890 Ma. The results of this study demonstrate that the Neoproterozoic (800-900 Ma)magmatism was not restricted to the Yangtze Block, but also occurred at the southeast margin of the North China Craton. [ABSTRACT FROM AUTHOR]

Abstract: Soil and water loss from sloping croplands is a major environmental problem that is attracting widespread attention across the world. Various soil protection techniques, such as terrace and contour tillage, have been used in recent years with limited results. Grass hedges and micro-basins are effective for reducing soil and water loss on sloping croplands in tropical and subtropical regions. However, grass hedges and micro-basins have not been adequately evaluated in temperate climatic regions (for example, in Northern China); thus, they would not be readily accepted by local farmers. In this study, the soil and water conservation effects of two native grass hedges (Pennisetum alopecuroides (Linn.) Spreng. and Arundinella hirta (Thunb.) C. Tanaka) and micro-basins were studied in the temperate regions of Northern China using simulated rainfall. The experiment included two parts: trial I and trial II. In trial I, three independent variables, including grass hedges (the Arundinella, the Pennisetum, and the control), slope gradient (5%, 10%, 15%, and 20%), and rainfall intensity (36mmh−1 and 63mmh−1) were considered. In trial II, the independent variables were changed to soil protective practice (the grass hedges, the micro-basins, and the control), slope gradient (5%, 10%, 15%, and 20%), and rainfall intensity (36mmh−1 and 63mm h−1). Next, the Vegetative Filter Strip Modeling System (VFSMOD) model was introduced to simulate the runoff and sediment intercepted by the grass hedges. Lastly, cost analysis was conducted based on the cost of labor and seeds or plants for the grass hedge and micro-basin trials. The use of Pennisetum hedges decreased the mean runoff and soil loss by 56% and 81%, the Arundinella hedges decreased the runoff and soil loss by 55% and 67%, and the micro-basins decreased the runoff and soil loss by 70% and 62%, respectively. Moreover, the runoff and sediment that passed through the grass hedges can be reasonably simulated with the VFSMOD model (the relative errors for runoff and sediment content were −19.1% and −14.6%, and the Nash–Sutcliffe efficiencies for runoff and sediment content were 0.91 and 0.85, respectively). Conversely, the grass hedges occupied 9% of the farmland in the study area and cost 5864 CNY per hectare. In addition, the micro-basins occupied 7% of the farmland and cost 3000 CNY per hectare. These results imply that grass hedges and micro-basins are cost-effective when compared with terraces, which cost more than 7401 CNY per hectare and typically occupy 18% of farmland. Overall, we conclude that the soil protective practices of using grass hedges or micro-basins are effective and efficient for decreasing soil and water loss on sloping croplands in temperate regions. Thus, these practices should be intensively recommended and used widely in similar climatic regions. [Copyright &y& Elsevier]

Reports on the discovery of eclogite inclusions in eastern China. Presence of monzodioritic porphyry in the early Jurassic intrusive complex in northern Anhui and northern Jiangsu, which emplaced in 191 Ma; Indication the intrusive complexes contain eclogite inclusions that belong to eclogite and garnet-pyroxenite; Evidence the inclusions underwent eclogite facies high-pressure metamorphism and amphibolite facies retrogressive metamorphism; Mention of almandine, as well as, omphacite and augite clinopyroxenes in garnets found in the eclogite inclusions; The mineral assemblage and P-T estimation results showing metamorphism conditions; Significance of the high-pressure xenoliths in understanding the composition and structure of deep crust in the North China Platform; Implication for understanding the subduction-collision-exhumation evolutional process of the Dabie-Sulu ultrahigh-pressure (UHP) metamorphic belt.

[Display omitted] • The Xintian complex is associated with a telescoped porphyry-epithermal system. • Influxes of mafic melts into felsic melts result in the emplacement of this complex. • High oxidation state and magmatic water are conducive to the Cu–Au mineralization. The Naozhi polymetallic veins classified into the intermediate-sulfidation (IS) type and the 2 km northwest Xintian porphyry Cu–Mo ore occurrence in the Yanbian area, Northeast China, constitute a telescoped porphyry-epithermal system. IS veins are surrounded by Early Jurassic granodiorite stocks (189 ± 1 Ma; zircon U-Pb) and Early Cretaceous andesite lava (128 – 130 Ma; zircon U-Pb). They are partially covered by younger pyroclastic rocks dated at 108 ± 2 Ma (Zircon U-Pb). The Xintian occurrence is connected in space and time with an intrusive complex including five sequential phases from gabbro diorite and granodiorite stocks through diorite porphyry dykes to granodiorite porphyry and granite porphyry stocks, with indistinguishable ages within errors (128 ± 1 Ma to 126 ± 1 Ma zircon 206Pb/238U by laser ablation inductively coupled plasma mass spectrometry). The broad compositional variations (eg., 52.24 – 69.23 wt% SiO 2) of the complex and the igneous mafic microgranular enclaves (MMEs) hosted by granodiorite stocks are likely responses to inputs of hot mafic melts into a shallow felsic magma chamber. Based on the trace element contents of zircons, the redox conditions during the crystallization of zircon minerals in equilibrium with the melts are evaluated by calculating the FMQ values. The early mafic phase (gabbro diorite; FMQ 4.60 ± 1.33) is more oxidized than later phases (granodiorite, diorite porphyry, granodiorite porphyry, and granite porphyry) with FMQ values of 1.70 ± 1.80 to 2.28 ± 2.36. The highly oxidizing conditions of associated magmas, as well as high magmatic water contents (>4%) because of ubiquitous biotite and amphibole in this complex, are conducive to escape of primary volatiles from shallow, fertile porphyry magmas, with consequent ore deposition in structurally optimal positions at Naozhi-Xintian. [ABSTRACT FROM AUTHOR]