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This paper analyses agricultural green efficiency and productivity by using the farming and livestock industries as case studies. To do so, nitrogen and phosphorus surpluses in arable land are measured by considering recycling of agricultural wastes in the farming and livestock ecosystem and defined as the undesirable output in agricultural production. The empirical analysis is based on data of rural areas in Anhui province, China, over the period of 2000 to 2017. It shows the existence of considerable nitrogen and phosphorus nutrient surplus in arable land, with phosphorus surplus keeps increasing. It also illustrates that nitrogen and phosphorus nutrients from manure were decreasing while those from the crop residues were increasing. The empirical assessment demonstrates that agricultural green efficiency tended to converge over time. Furthermore, agricultural green total factor productivity showed an overall increasing trend, although its components, efficiency change and technological progress, moved in opposite directions in most years. Finally, some useful policy recommendations are provided in this paper. [ABSTRACT FROM AUTHOR]

The Permian–Triassic boundary (PTB) volcanic tuffs are widely distributed in the East Palaeo‐Tethys region, but their age and origin have been controversial. The Permian–Triassic deep‐water sediments in the northeastern margin of South China are favourable research objects, and we report new results from the PTB deep basin sediments in the Susong area, Anhui Province, in this paper. Two volcanic tuffs are found in the Zuoshan PTB in the Zuoshan section, and Laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) U–Pb zircon dating indicates that the upper and lower tuffs are 251.3 ± 1.7 Ma and 252.3 ± 2.1 Ma, respectively. The PTB age is 251.6 Ma according to a numerical interpolation method of the average deposition rate of the PTB. Fusulinids and non‐fusulinid foraminifers in the limestone overlying the lower tuff define the rock as end‐Permian. Zircon trace elements show that both tuffs are sourced from felsic volcanism in continental arc background, and their source magmas were derived from the continental crust. Zircons of PTB age from the upper tuff on the bottom of the Triassic have negative εHf(t) value from −8.02 to −3.75, and the Palaeo‐Mesoproterozoic two‐stage model ages of 1502–1780 Ma, showing that their source rocks were only derived from the remelting of the Palaeo‐Mesoproterozoic continental crust. The zircons from the lower tuff on the top of the Permian show two types, including negative εHf(t) values from −6.48 to −1.25 and Palaeo‐Mesoproterozoic two‐stage model ages of 1350–1679 Ma, and positive εHf(t) values from +3.98 to +10.15, and Neoproterozoic two‐stage model ages of 629–1023 Ma, indicating that their sources were derived from the reworking of the Palaeo‐Mesoproterozoic continental crust and early Neoproterozoic depleted mantle joined in juvenile crust growth in the northern margin of the South China Block at the beginning of the collision between the South China and North China blocks. The initial collision started no later than 252.3 Ma and developed significantly from east to west. [ABSTRACT FROM AUTHOR]

Amphibians and reptiles, especially the critically endangered Chinese alligators, are vulnerable to climate change. Historically, the decline in suitable habitats and fragmentation has restricted the distribution of Chinese alligators to a small area in southeast Anhui Province in China. However, the effects of climate change on range‐restricted Chinese alligator habitats are largely unknown. We aimed to predict current and future (2050s and 2070s) Chinese alligator distribution and identify priority conservation areas under climate change. We employed species distribution models, barycenter migration analyses, and the Marxian model to assess current and future Chinese alligator distribution and identify priority conservation areas under climate change. The results showed that the lowest temperature and rainfall seasonality in the coldest month were the two most important factors affecting the distribution of Chinese alligators. Future predictions indicate a reduction (3.39%–98.41%) in suitable habitats and a westward shift in their distribution. Further, the study emphasizes that suitable habitats for Chinese alligators are threatened by climate change. Despite the impact of the Anhui Chinese Alligator National Nature Reserve, protection gaps persist, with 78.27% of the area lacking priority protected area. Our study provides crucial data for Chinese alligator adaptation to climate change and underscores the need for improved conservation strategies. Future research should refine conservation efforts, consider individual plasticity, and address identified limitations to enhance the resilience of Chinese alligator populations in the face of ongoing climate change. [ABSTRACT FROM AUTHOR]

To solve the problems of voltage violation and fast voltage fluctuation caused by photovoltaic (PV) grid connections in distribution networks, a two‐stage coordinated voltage control strategy for PV inverters with multimode coordinated operation in distribution networks (DNs) is proposed. It is based on the characteristics of PV inverters that can be regulated rapidly and continuously. First, the voltage control process is divided into two control stages according to the voltage change rate, and the corresponding voltage control models are established. Then, the operating modes of PV inverters are classified into three modes: economic prevention, economic control, and efficient control. Different operating modes are used to adapt to the two‐stage voltage control. Finally, a voltage fast control solution algorithm is proposed, which considers adaptive time delays and combines local measurement, prediction, and communication information to update control commands. The effectiveness and feasibility of the proposed voltage control strategy were demonstrated through simulation tests on a real 10‐kV line with a high PV penetration rate in the Anhui province of China. The results show that the proposed strategy can prevent voltage violation and sudden changes and can smooth out voltage fluctuation. [ABSTRACT FROM AUTHOR]

BACKGROUND Chinese sprangletop (Leptochloa chinensis (L.) Nees) is an invasive grass weed severely infesting rice fields across China. In October 2020, a suspected resistant Leptochloa chinensis population HFFD3 that survived the acetyl‐CoA carboxylase (ACCase)‐inhibiting herbicide cyhalofop‐butyl applied at its field‐recommended rate was collected from a rice field in Feidong County, Anhui Province, China. This study aimed to determine the resistance profile of HFFD3 to ACCase inhibitors and to investigate its mechanisms of resistance to cyhalofop‐butyl. RESULTS: Single‐dose testing confirmed that HFFD3 had evolved resistance to cyhalofop‐butyl. Two loci encoding plastidic ACCase were each amplified from the susceptible (S) and resistant (R, HFFD3) individual plants. Target gene sequencing and derived cleaved amplified polymorphic sequence assay revealed all the R plants carried a Trp‐2027‐Leu substitution in their ACCase1,2 copies. Dose–response bioassays revealed that HFFD3 was highly resistant to cyhalofop‐butyl and exhibited cross‐resistance to metamifop, fenoxaprop‐P‐ethyl, quizalofop‐P‐ethyl, and clethodim. Pre‐treatment with piperonyl butoxide and 4‐chloro‐7‐nitrobenzoxadiazole considerably reversed the resistance of the R plants to cyhalofop‐butyl, by 23% and 43%, respectively. Liquid chromatography–tandem mass spectrometry analysis suggested the metabolic rates of cyhalofop‐butyl were significantly faster in the R than in the S plants. CONCLUSION: This study confirmed the first case of an arable weed species featuring cross‐resistance to ACCase‐inhibiting herbicides due to a novel Trp‐2027‐Leu mutation of ACCase. Target gene mutation and cytochrome P450s‐ and glutathione‐S‐transferases‐involved enhanced metabolism may have simultaneously participated in the resistance of HFFD3 population to cyhalofop‐butyl. [ABSTRACT FROM AUTHOR]

The competitive relationship and coexistence pattern among close related species have long been one of the hot issues in ecological research. Interspecies interactions can exert important influences on the local distribution of rare species. Black muntjac Muntiacus crinifrons is an endemic species to eastern China, currently restricted to limited regions. In contrast, Chinese muntjac Muntiacus reevesi is the most common and widespread deer in southern China. Both species co‐occur in southern Anhui and western Zhejiang Province. Little is known about the interaction of these two sympatric‐related species. In this study, to investigate the site use determinants and co‐occurrence pattern of the two sympatric muntjac species, we conducted a camera trap survey across about 250 km2 in mountainous area of southern Anhui Province, China. We adopted a multistep approach to incorporate habitat preferences while modeling occupancy and detection. We found that the two species did not separate along elevation gradient (range from 400 m to 1,400 m) as described in previous studies. Results of single‐species occupancy models indicated that elevation had positive effects on the site use of both species, while slope had an opposite influence on their site use. Positive effects of elevation on the site use implied that both species try to avoid human interference at low elevations. Significant negative effect of slope on the site use of black muntjac suggested that the species prefer habitat with gentle slope and avoided steep. Co‐occurrence models and species interaction factors provided evidence that the two muntjac species had an independent occupancy (ψBM CM = ψBM cm, SIF = 1) and exhibited a positive species interaction in detection probability (pBM < rBM CM). Combined with the results of previous studies, we suggested that it was fine differentiation in microhabitats and food resources utilization rather spatial or temporal segregation that allowed the two species co‐occurrence. The site use determinants revealed in our study would be useful for the habitat conservation and restoration for the rare black muntjac, and the co‐occurrence pattern of the two sympatric muntjac species could provide useful information for deep understanding of the coexistence mechanism among forest‐dwelling ungulates. [ABSTRACT FROM AUTHOR]

Cretaceous syntectonic growth strata in terrigenous basins in Southeast China have scarcely been reported in previous studies. This work focusses on the growth strata of the Early Cretaceous red beds in the East Yangtze Block (EYB), especially in the Huangshan Basin in southern Anhui Province, to help determine the Late Mesozoic tectonic domain and the precise timing of the initiation of extensional tectonics in Southeast China. Field observations show that the dip angles of the red conglomerate‐bearing sandstones from the lower part of the Huizhou Fm. vary from 49° to gentle dips towards the basin centre and that the visible and estimated thickness within a single bed increases slightly downward from the upper to the lower part. These characteristics indicate that the sedimentary area of the Early Cretaceous Huizhou Formation (Fm.) has undergone an extensional process with the expansion and deepening of the sedimentary basin by rotation of the border surface (limb) and thus deposited the extension growth strata simultaneously with (or closely after) the 139 Ma Shiling volcanic activity. Caused by a NW‐SE‐oriented extensional stress field since ca. 140 Ma, a model in which NE‐SW‐oriented tectonic lines transform to E‐W‐trending tectono‐magmatic belts by intersecting and inheriting the previous E‐W‐trending tectonic fabrics is established in the present work. Consequently, these phenomena are influenced by Palaeo‐Pacific Plate rollback and the inheritance of a structural framework from the regional basement strata and deformation series. [ABSTRACT FROM AUTHOR]

The article focuses on a research paper discussing the formation of the banded iron formation (BIF) in Huoqiu iron ore field in Western Anhui Province, China. It offers information on several metamorphic rocks in the region including dolomitic marble, schist and amphibolite. It also discusses iron mineralization and ore genesis of BIF in Huoqiu.

The characterization of lime mortars has become of primary importance in order to obtain information about the raw ingredients and building technology of ancient masonry structures. Five different samples from Anhui province, China, representing two types of lime mortar‐based materials: joint mortars between the bricks of the city wall and lime mortar sealing a tomb coffin, were collected for analysis. Archaeological information about the samples was reported and studies into the microtextural features and mineralogical compositions of those mortars were performed via a multi‐analytical approach. The joint lime mortars between the bricks of city walls, including Mingzhongdu city wall, Mingzhongdu Xihua gate foundation, Zhengyangguan city wall and She county city wall, were found to be aerial lime mortars. The lime mortar from Nanling Tieguai Song dynasty tomb was analysed and found to be a pozzolanic mortar consisting of lime, clay, sand and cocciopesto‐like materials. The analytical results serve as a critical reference for the maintenance and restoration of ancient city walls in Anhui province, and as a starting point for searching for ancient Chinese pozzolanic mortars and technology for making those mortars. [ABSTRACT FROM AUTHOR]

Correct identification of water inrush sources is particularly important to prevent and control mine water disasters. Hydrochemical analysis, Fisher discriminant analysis, and geothermal verification analysis were used to identify and verify the water sources of the multi‐aquifer groundwater system in Gubei coal mine, Anhui Province, North China. Results show that hydrochemical water types of the Cenozoic top aquifer included HCO3–Na+K–Ca, HCO3–Na+K–Mg and HCO3–Na+K, and this aquifer was easily distinguishable from other aquifers because of its low concentration of Na++K+ and Cl–. The Cenozoic middle and bottom aquifers, the Permian fissure aquifer, and the Taiyuan and Ordovician limestone aquifers were mainly characterized by the Cl–Na+K and SO4–Cl‐Na+K or HCO3–Cl–Na+K water types, and their hydrogeochemistries were similar. Therefore, water sources could not be identified via hydrochemical analysis. Fisher model was established based on the hydrogeochemical characteristics, and its discrimination rate was 89.19%. Fisher discrimination results were improved by combining them with the geothermal analysis results, and this combination increased the identification rate to 97.3 % and reasonably explained the reasons behind two water samples misjudgments. The methods described herein are also applicable to other mines with similar geological and hydrogeological conditions in North China. [ABSTRACT FROM AUTHOR]

Seventy‐three Lu'an guapian tea (LAGP) samples were collected from 11 growing locations in the city of Lu'an, Anhui Province, China. Through high‐performance liquid chromatography, 18 amino acids, along with gallic acid, caffeine, and five catechins, were quantitatively detected. Hierarchical cluster, correlation and principal component analysis, and a support vector machine were used for geographical discrimination. The findings suggested that the differences in tea quality between the inner and outer mountain regions are related to isoleucine, leucine, phenylalanine, and valine contents, with a correlation coefficient of more than 0.85. Principal component analysis combining with support vector machine was a feasible method. The identification rates for the inner and outer mountains were 97.96% in the training set and 95.83% in the prediction set. Furthermore, the identification rates for the three counties were 91.84% and 95.83% in the training and prediction sets, respectively. [ABSTRACT FROM AUTHOR]

The article presents a study which focuses on the Xiaohe gold deposit situated in Jiangnan block, South Anhui, China by means of element analysis, geological survey, and statistical research on geochemical database of magmatic rocks, sedimentary rocks, and gold deposits. Topics include relationship between gold formation and regional structure, geologic strata and magma rock; regional geological background and characteristics of Au mineralization.