Simulation Of Non-Point Source Pollution In Zhang River Basin

Since 1987, the China Government started the “The Water Resource Protection and Management of Haihe River Basin” program aimed at tackling the problem of water pollution and realizing the comprehensive control of the ecosystem and water resources in the whole basin. This study aims to model one of the program’s catchments – Zhang River Basin (ZRB), which is a typical area with the striking water scarcity and water quality deterioration in Haihe River Basin (HRB). The distributed hydrological model SWAT(Soil and Water Assessment Tool) was used to simulate all related processes affecting water quantity, sediment, and nutrient loads in the catchment using historical flow and meteorological data for 5 years(January 2005-December 2009). Data on management practices (crop rotation, planting date, fertilizer quantity and irrigation) were included in the model during the simulation period of 5 years .The main objectives of this study were to evaluate the long-term impact of point source (PS) and non-point source (NPS) pollution on water quality loadings and to determine the contribution of point and non-point sources in the entire catchment. Based on the simulated results, the spatio-temporal distributions of flow, sediment and nutrient loads are analyzed; hence the critical areas of soil erosion and nutrient loss were identified, so as to provide the scientific basis for the water resources allocation and pollutant control in the basin

Use of 18O Labels to Monitor Deamidation during Protein and Peptide Sample Processing

Nonenzymatic deamidation of asparagine residues in proteins generates aspartyl (Asp) and isoaspartyl (isoAsp) residues via a succinimide intermediate in a neutral or basic environment. Electron capture dissociation (ECD) can differentiate and quantify the relative abundance of these isomeric products in the deamidated proteins. This method requires the proteins to be digested, usually by trypsin, into peptides that are amenable to ECD. ECD of these peptides can produce diagnostic ions for each isomer; the c· + 58 and z − 57 fragment ions for the isoAsp residue and the fragment ion ((M + nH)(n−1)+· − 60) corresponding to the side-chain loss from the Asp residue. However, deamidation can also occur as an artifact during sample preparation, particularly when using typical tryptic digestion protocols. With 18O labeling, it is possible to differentiate deamidation occurring during trypsin digestion which causes a +3 Da (18O1 + 1D) mass shift from the pre-existing deamidation, which leads to a +1-Da mass shift. This paper demonstrates the use of 18O labeling to monitor three rapidly deamidating peptides released from proteins (calmodulin, ribonuclease A, and lysozyme) during the time course of trypsin digestion processes, and shows that the fast (̃4 h) trypsin digestion process generates no additional detectable peptide deamidations

The impact of species phylogenetic relatedness on invasion varies distinctly along resource versus non-resource environmental gradients

1. Understanding why some, but not other, plant communities are vulnerable to alien invasive species is essential for predicting and managing biological invasions. Darwin proposed two seemingly contradictory hypotheses on how native-invader relatedness influences invasion success, emphasizing, respectively, the importance of environmental filtering and competition between natives and invaders. Despite much recent empirical research on this topic, reconciling these two hypotheses, known as Darwin's naturalization conundrum, remains a challenge. 2. Using plot-level data from natural forests along elevational transects covering strong environmental gradients, we examined whether the invasion of the globally invasive species crofton weed (Ageratina adenophora) can be explained by environmental filtering and/or competition from closely related species linked to environmental gradients. 3. Abundant precipitation, warm temperatures, open canopies and postfire environments facilitated A. adenophora invasion, whereas resident taxonomic richness suppressed its invasion. Importantly, we found that invader-resident relatedness had a strong negative effect on invader cover under resource scarcity conditions (e.g. low water availability), but not under non-resource environmental stress gradients (e.g. low temperature). 4. Synthesis and applications. Our results suggest that the impact of species phylogenetic relatedness on invasion success varies distinctly along resource versus non-resource environmental gradients. These results help to reconcile Darwin's naturalization conundrum, thereby improving the ability to predict the success of alien plant invasions in a changing world. Our study stresses the need to consider adjusting forest species composition to strengthen their resistance to invasion, while taking into account resource and non-resource environmental gradients, particularly after wildfires

Postseismic Restoration of the Ecological Environment in the Wenchuan Region Using Satellite Data

Using Landsat remote-sensing data combined with geological information extracted from ALOS and Sentinel-1A radar data, the ecological environment was evaluated in the years 2007, 2008, 2013, and 2017 through gray correlation analysis on the basis of the construction of the pressure-state-response model. The main objective of this research was to assess the ecological environment changes in Wenchuan County before and after the earthquake, and to provide reference for future social development and policy implementation. The grading map of the ecological environment was obtained for every year, and the ecological restoration status of Wenchuan County after the earthquake was evaluated. The results showed that the maximum area cover at a “safe” ecological level was over 46.4% in 2007. After the 2008 earthquake, the proportion of “unsafe” and “very unsafe” ecological levels was 40.0%, especially around the Lancang River and the western mountain area in Wenchuan County. After five years of restoration, ecological conditions were improved, up to 48.0% in the region. The areas at “critically safe” and above recovered to 85.5% in 2017 within nine years after the deadly Wenchuan earthquake of May 12, 2008. In this paper, we discuss the results of detailed analysis of ecological improvements and correlation with the degrees of pressure, state, and response layers of the Pressure-State-Response (PSR) model

Fault Attack on the Authenticated Cipher ACORN v2

Fault attack is an efficient cryptanalysis method against cipher implementations and has attracted a lot of attention in recent public cryptographic literatures. In this work we introduce a fault attack on the CAESAR candidate ACORN v2. Our attack is done under the assumption of random fault injection into an initial state of ACORN v2 and contains two main steps: fault locating and equation solving. At the first step, we first present a fundamental fault locating method, which uses 99-bit output keystream to determine the fault injected location with probability 97.08%. And then several improvements are provided, which can further increase the probability of fault locating to almost 1. As for the system of equations retrieved at the first step, we give two solving methods at the second step, that is, linearization and guess-and-determine. The time complexity of our attack is not larger than c·2179.19-1.76N at worst, where N is the number of fault injections such that 31≤N≤88 and c is the time complexity of solving linear equations. Our attack provides some insights into the diffusion ability of such compact stream ciphers

Land-Use/Land-Cover Changes and Their Influence on the Ecosystem in Chengdu City, China during the Period of 1992–2018

Due to urban expansion, economic development, and rapid population growth, land use/land cover (LULC) is changing in major cities around the globe. Quantitative analysis of LULC change is important for studying the corresponding impact on the ecosystem service value (ESV) that helps in decision-making and ecosystem conservation. Based on LULC data retrieved from remote-sensing interpretation, we computed the changes of ESV associated with the LULC dynamics using the benefits transfer method and geographic information system (GIS) technologies during the period of 1992–2018 following self-modified coefficients which were corrected by net primary productivity (NPP). This improved approach aimed to establish a regional value coefficients table for facilitating the reliable evaluation of ESV. The main objective of this research was to clarify the trend and spatial patterns of LULC changes and their influence on ecosystem service values and functions. Our results show a continuous reduction in total ESV from United States (US) $1476.25 million in 1992, to US$1410.17, $1335.10, and$1190.56 million in 2001, 2009, and 2018, respectively; such changes are attributed to a notable loss of farmland and forest land from 1992–2018. The elasticity of ESV in response to changes in LULC shows that 1% of land transition may have caused average changes of 0.28%, 0.34%, and 0.50% during the periods of 1992–2001, 2001–2009, and 2009–2018, respectively. This study provides important information useful for land resource management and for developing strategies to address the reduction of ESV