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The effect of the combined application of nano-hydroxyapatite (NHAP) or nano-carbon black (NCB) on the phytoextraction of Pb by ryegrass was investigated as an enhanced remediation technique for soils by field-scale experiment. After the addition of 0.2% NHAP or NCB to the soil, temporal variation of the uptake of Pb in aboveground parts and roots were observed. Ryegrass shoot concentrations of Pb were lower with nano-materials application than without nano-materials for the first month. However, the shoot concentrations of Pb were significantly increased with nano-materials application, in particular NHAP groups. The ryegrass root concentrations of Pb were lower with nano-materials application for the first month. These results indicated that nano-materials had significant effects on stabilization of lead, especially at the beginning of the experiment. Along with the experimental proceeding, phytotoxicity was alleviated after the incorporation of nano-materials. The ryegrass biomass was significantly higher with nano-materials application. Consequently, the Pb phytoextraction potential of ryegrass significantly increased with nano-materials application compared to the gounps without nano-materials application. The total removal rates of soil Pb were higher after combined application of NHAP than NCB. NHAP is more suitable than NCB for in-situ remediation of Pb-contaminated soils. The ryegrass translocation factor exhibited a marked increase with time. It was thought that the major role of NHP and NBA might be to alleviate the Pb phytotoxicity and increase biomass of plants.

Ni3Mo3C was prepared by a modified organic colloid method and explored as anode catalyst for high-performance microbial fuel cell (MFC) based on Klebsiella pneumoniae (K. pneumoniae). The prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET). The activity of the sample as anode catalyst for MFC based on K. pneumoniae was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and polarization curve measurement. The results show that the adding of nickel in Mo2C increases the BET surface area of Mo2C and improves the electrocatalytic activity of Mo2C towards the oxidation of microbial fermentation products. The power density of MFC with 3 mg cm(-2) Ni3Mo3C anode is far higher than that of the MFC with carbon felt as anode without any catalyst, which is 19 % higher than that of Mo2C anode and produced 62 % as much as that of Pt anode, indicating that Ni3Mo3C is comparative to noble metal platinum as anode electrocatalyst for MFCs by increasing the loading.

This study examined the effects of climate change on rice production in 30 Chinese provinces spanning 1998–2017. The study used the pooled mean group technique to capture the long-run and short-run effects of changing climatic conditions on rice production. It further employed the Dumitrescu–Hurlin panel causality test to examine the path of causality between the key variables and rice production. The study found that, in the long run, average temperature negatively influenced rice production, but average rainfall had a positive effect on rice production. The results indicated that the cultivated area and fertilizer usage were positively related to rice production in the long run. The short-run results accentuated that average temperature favourably influenced nationwide rice production, whereas average rainfall had no substantial effect on national rice production. The cultivated area had a significant positive short-term relationship with rice production, although the impact of fertilizer usage on rice production was negligible in the short run. Besides, the results established a bidirectional causality between rice output and the cultivated area, but there was a one-way causality running from fertilizer usage to rice output. Finally, the results indicated that, except for rainfall, a unidirectional causality exists between temperature and rice production. The study, therefore, recommends that in the case of crop failure due to weather conditions, policymakers could implement a new pricing policy to mitigate the deterioration of the farmers’ income. The government must also develop and implement an insurance scheme that compensates farmers for catastrophes induced by rainfall deficiency.

Increased use of ethanol-blended gasoline (gasohol) and its potential release into the subsurface have spurred interest in studying the biodegradation of and interactions between ethanol and gasoline components such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) in groundwater plumes. The preferred substrate status and the high biological oxygen demand (BOD) posed by ethanol and its biodegradation products suggests that anaerobic electron acceptors (EAs) will be required to support in situ bioremediation of BTEX. To develop a strategy for aromatic hydrocarbon bioremediation and to understand the impacts of ethanol on BTEX biodegradation under strictly anaerobic conditions, a microcosm experiment was conducted using pristine aquifer sand and groundwater obtained from Canadian Forces Base Borden, Canada. The initial electron accepter pool included nitrate, sulfate and/or ferric iron. The microcosms typically contained 400 g of sediment, 600 approximately 800 ml of groundwater, and with differing EAs added, and were run under anaerobic conditions. Ethanol was added to some at concentrations of 500 and 5000 mg/L. Trends for biodegradation of aromatic hydrocarbons for the Borden aquifer material were first developed in the absence of ethanol, The results showed that indigenous microorganisms could degrade all aromatic hydrocarbons (BTEX and trimethylbenzene isomers-TMB) under nitrate- and ferric iron-combined conditions, but not under sulfate-reducing conditions. Toluene, ethylbenzene and m/p-xylene were biodegraded under denitrifying conditions. However, the persistence of benzene indicated that enhancing denitrification alone was insufficient. Both benzene and o-xylene biodegraded significantly under iron-reducing conditions, but only after denitrification had removed other aromatics. For the trimethylbenzene isomers, 1,3,5-TMB biodegradation was found under denitrifying and then iron-reducing conditions. Biodegradation of 1,2,3-TMB or 1,2,4-TMB was slower under iron-reducing conditions. This study suggests that addition of excess ferric iron combined with limited nitrate has promise for in situ bioremediation of BTEX and TMB in the Borden aquifer and possibly for other sites contaminated by hydrocarbons. This study is the first to report 1,2,3-TMB biodegradation under strictly anaerobic condition. With the addition of 500 mg/L ethanol but without EA addition, ethanol and its main intermediate, acetate, were quickly biodegraded within 41 d with methane as a major product. Ethanol initially present at 5000 mg/L without EA addition declined slowly with the persistence of unidentified volatile fatty acids, likely propionate and butyrate, but less methane. In contrast, all ethanol disappeared with repeated additions of either nitrate or ferric iron, but acetate and unidentified intermediates persisted under iron-enhanced conditions. With the addition of 500 mg/L ethanol and nitrate, only minor toluene biodegradation was observed under denitrifying conditions and only after ethanol and acetate were utilized. The higher ethanol concentration (5000 mg/L) essentially shut down BTEX biodegradation likely due to high EA demand provided by ethanol and its intermediates. The negative findings for anaerobic BTEX biodegradation in the presence of ethanol and/or its biodegradation products are in contrast to recent research reported by Da Silva et al. [Da Silva, M.L.B., Ruiz-Aguilar, G.M.L., Alvarez, P.J.J., 2005. Enhanced anaerobic biodegradation of BTEX-ethanol mixtures in aquifer columns amended with sulfate, chelated ferric iron or nitrate. Biodegradation. 16, 105-114]. Our results suggest that the apparent conservation of high residual labile carbon as biodegradation products such as acetate makes natural attenuation of aromatics less effective, and makes subsequent addition of EAs to promote in situ BTEX biodegradation problematic.

In this study, a novel biomass pretreatment process using three kinds of deep eutectic solvents (DESs) was developed to improve saccharification efficiency and lignin valorization. The major components of xylose residue including cellulose and lignin fractions were released, recovered and utilized. Pretreatment with betaine/lactic acid system at 120 °C for 2 h was found to be the optimal conditions with prominently increased enzymatic digestibility (from 55.3% to 96.8%). The efficient conversion was mainly ascribed to the significant delignification efficiency of 81.6% after betaine/lactic acid pretreatment, which caused incompact structure and corrosive surface of treated xylose residue. The recoverable lignin had high purity, low molecular weight (630-2040 g/mol) and polydispersity (1.07-1.76). Based on the comprehensive analysis, the one-pot DESs system provides us a facile and effective approach for whole components valorization of lignocellulosic materials.

We contribute to the literature on the effectiveness of aid and to energy poverty literature by providing the first study that examines the effect of aid on energy poverty. Using eight rounds of the Demographic and Health Surveys (DHS) and sub-national aid data for Senegal, we find that aid lowers the probability of energy poverty. Our main results show that living within a 25km radius of an aid project reduces the likelihood of being energy poor by 4.5 percentage points. This finding is robust to a suite of sensitivity checks. We also examine four channels through which aid could influence energy – income poverty, education, health and economic growth – and find that income poverty, education and economic growth are mechanisms through which aid transmits to energy poverty.

The non-Antarctic Notothenioidei families, Bovichtidae, Pseudaphritidae and Eleginopsidae, diverged early from the main notothenioid lineage. They are important in clarifying the early evolutionary processes that triggered notothenioid evolution in the Antarctic. The early-diverged group represents 8% of all notothenioid species and never established themselves on the Antarctic shelf. Most attention has been paid to the Antarctic notothenioids and their limited physiological tolerance to climate change and increased temperatures. In this review, we discuss key life history traits that are characteristic of the non-Antarctic early-diverged notothenioid taxa as well as the genetic resources and population differentiation information available for this group. We emphasise the population fitness and dynamics of these species and indicate how resource management and conservation of the group can be strengthened through an integrative approach. Both Antarctic waters and the non-Antarctic regions face rapid temperature rises combined with strong anthropogenic exploitation. While it is expected that early-diverged notothenioid species may have physiological advantages over high Antarctic species, it is difficult to predict how climate changes might alter the geographic range, behaviour, phenology and ultimately genetic variability of these species. It is possible, however, that their high degree of endemism and dependence on local environmental specificities to complete their life cycles might enhance their vulnerability.

The ability to reuse winery wastewater would be of significant benefit to the wine industry, as it could potentially be a cost-effective method of wastewater management, whilst at the same time providing a valuable water resource. This study investigated the effects of different dilutions of a semi-synthetic winery wastewater on the growth and germination of four common crop species in a glasshouse study; barley (Hordeum vulgare), millet (Pennisetum glaucum), lucerne (Medicago sativa) and phalaris (Phalaris aquatica). The wastewater caused a significant delay in the germination of lucerne, millet and phalaris, although overall germination percentage of all species was not affected. Vegetative growth was significantly reduced in all species, with millet being the most severely affected. The germination index of barley correlated very highly (r(2)=0.99) with barley biomass, indicating that barley seed germination bioassays are highly relevant to plant growth, and therefore may be of use as a bioassay for winery wastewater toxicity.

The genus Quercus is one of the most important tree species in Turkey. However, little is known on the ecological preferences of Turkish oak species regarding climate. We analyzed species response curves using a HOF-model approach to describe the general pattern of oak distributions along climatic gradients and to identify the driving climatic factors for eight oak species in Turkey. While climate data were extracted from the free available worldclim dataset, occurrence data on oak species were assembled from the literature into a vegetation database (n = 1,104). From the analyzed species response curves, only fa ew (16%) showed unimodal responses, while most were linear (31%) or exhibited a threshold response (31%). The driving factors were seasonality of temperature and seasonality of precipitation, indicating that Turkish oak species can be characterized best by the preference of climatic stability. These findings have important implications for conservation and climate change research, which usually focuses on trends of the mean values of temperature or precipitation but less often on the seasonality. In this study, we further tested whether niche optima derived from raw mean values of occurrences could replace missing model optima due to non-responsiveness of HOF models of type I. However, we did not find this to be a satisfactory solution. Finally, we discuss the need for the construction of a national database based on phytosociological relevés for Turkey.