Spatial-temporal changes and driving factors of eco-environmental quality in the Three-North region of China

Eco-environmental quality is a measure of the suitability of the ecological environment for human survival and socioeconomic development.Understanding the spatial-temporal distribution and variation trend of eco-environmental quality is essential for environmental protection and ecological balance.The remote sensing ecological index(RSEI)can quickly and objectively quantify eco-environmental quality and has been extensively utilized in regional ecological environment assessment.In this paper,Moderate Resolution Imaging Spectroradiometer(MODIS)images during the growing period(July-September)from 2000 to 2020 were obtained from the Google Earth Engine(GEE)platform to calculate the RSEI in the three northern regions of China(the Three-North region).The Theil-Sen median trend method combined with the Mann-Kendall test was used to analyze the spatial-temporal variation trend of eco-environmental quality,and the Hurst exponent and the Theil-Sen median trend were superimposed to predict the future evolution trend of eco-environmental quality.In addition,ten variables from two categories of natural and anthropogenic factors were analyzed to determine the drivers of the spatial differentiation of eco-environmental quality by the geographical detector.The results showed that from 2000 to 2020,the RSEI in the Three-North region exhibited obvious regional characteristics:the RSEI values in Northwest China were generally between 0.2 and 0.4;the RSEI values in North China gradually increased from north to south,ranging from 0.2 to 0.8;and the RSEI values in Northeast China were mostly above 0.6.The average RSEI value in the Three-North region increased at an average growth rate of 0.0016/a,showing the spatial distribution characteristics of overall improvement and local degradation in eco-environmental quality,of which the areas with improved,basically stable and degraded eco-environmental quality accounted for 65.39%,26.82%and 7.79%of the total study area,respectively.The Hurst exponent of the RSEI ranged from 0.20 to 0.76 and the future trend of eco-environmental quality was generally consistent with the trend over the past 21 years.However,the areas exhibiting an improvement trend in eco-environmental quality mainly had weak persistence,and there was a possibility of degradation in eco-environmental quality without strengthening ecological protection.Average relative humidity,accumulated precipitation and land use type were the dominant factors driving the spatial distribution of eco-environmental quality in the Three-North region,and two-factor interaction also had a greater influence on eco-environmental quality than single factors.The explanatory power of meteorological factors on the spatial distribution of eco-environmental quality was stronger than that of topographic factors.The effect of anthropogenic factors(such as population density and land use type)on eco-environmental quality gradually increased over time.This study can serve as a reference to protect the ecological environment in arid and semi-arid regions.

Eco-environmental Quality Evaluation of Manasi River Basin in Recent 30 Years

Taking the Technical Specifications of Eco-environmental Quality Assessment enacted by the State Environmental Protection Administration in 2006 as the conceptual framework model and improving some indices and weights in the regulation,the eco-environmental assessment index system for Manas River Basin was established,and the eco-environmental quality index (EQI) of this basin from 1976 to 2005 was assessed based on the related data.The results indicated that the ecological quality index increased to 48.26 from 34.44 during 1976-2005.The biologic abundance index,vegetation coverage index and land deterioration index decreased,while there was an increase in water reticulation density index,environmental quality index and pollution load index,so the improvement and deterioration of the ecological environment coexisted in the basin.On the whole,the poor state of the basin ecological environment had turned into a general state,and the eco-environmental quality was developed towards favorable circle.The results also showed that the improved calculating method of EQI accorded with the actual situation of the research area.

Relationship between spatio-temporal evolution of soil pH and geological environment/surface cover in the eastern Nenjiang River Basin of Northeast China during the past 30 years

To illuminate the spatio-temporal variation characteristics and geochemical driving mechanism of soil pH in the Nenjiang River Basin,the National Multi-objective Regional Geochemical Survey data of topsoil,the Second National Soil Survey data and Normalized Difference Vegetation Index(NDVI)were analyzed.The areas of neutral and alkaline soil decreased by 21100 km^(2)and 30500 km^(2),respectively,while that of strongly alkaline,extremely alkaline,and strongly acidic soil increased by 19600 km^(2),18200 km^(2),and 15500 km^(2),respectively,during the past 30 years.NDVI decreased with the increase of soil pH when soil pH>8.0,and it was reversed when soil pH<5.0.There were significant differences in soil pH with various surface cover types,which showed an ascending order:Arbor<reed<maize<rice<high and medium-covered meadow<low-covered meadow<Puccinellia.The weathering products of minerals rich in K_(2)O,Na_(2)O,CaO,and MgO entered into the low plain and were enriched in different parts by water transportation and lake deposition,while Fe and Al remained in the low hilly areas,which was the geochemical driving mechanism.The results of this study will provide scientific basis for making scientific and rational decisions on soil acidification and salinization.

Land cover change and eco-environmental quality response of different geomorphic units on the Chinese Loess Plateau

Land cover in the Chinese Loess Plateau has undergone dramatic changes since the late 1980s.Revealing the trend in land cover change and eco-environmental quality response of different geomorphic units in this stage is a realistic requirement for promoting sustainable development of the Chinese Loess Plateau.Based on the data of geomorphic units and land cover in 1990,2000,2010 and 2018 of the Chinese Loess Plateau,we studied the trend of land cover change and eco-environmental quality response of different geomorphic units by using a significance index of land cover change,a proportion index of land cover change and an eco-environmental response model.The results indicated that from 1990 to 2018,the areas of forestland and construction land substantially increased,whereas those of cropland,grassland,wetland and unused land considerably decreased.Land cover change exhibited large geomorphic differences,and the main conversion of land cover was from cropland into other land types.Unstable trend of land cover change in the loess tablelands and sandy loess hills declined,whereas the unstable trends in the other geomorphic units enhanced.Eco-environmental quality varied among different geomorphic units.The expansion of construction land and degradation of forestland,grassland and wetland resulted in the deterioration of eco-environmental quality.The conversion of cropland and unused land into forestland and grassland,and the conversion of grassland into forestland were the main factors that drove the improvement of eco-environmental quality.The findings of this study may provide theoretical reference and support decision making for the optimization of land use structure and the improvement of eco-environmental quality on the Chinese Loess Plateau.

Dynamic Assessment on Regional Eco-environmental Quality Using AHP-Statistics Model—A Case Study of Chaohu Lake Basin

An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality.

Assessing the impacts of ecological-living-productive land changes on eco-environmental quality in Xining City on Qinghai-Tibet Plateau, China

The Ecological-living-productive land(ELPL)classification system was proposed in an effort to steer China's land pattern to an ecological-centered path,with the development model shifting from a single function into more integrated multifunction land use.The focus is coordinating the man-land contradictions and developing an intensive,efficient and sustainable land use policy in an increasingly tense relationship between humans and nature.Driven by socioeconomic change and rapid population growth,many cities are undergoing urban sprawl,which involves the consumption of cropland and ecological land and threatens the ecological balance.This paper aims to quantitatively analyze the critical effects of ELPL changes on eco-environmental quality according to land use classification based on leading function of ecology,living and production from 1990 to 2015 with a case study of Xining City.Also,four future land use scenarios were simulated for 2030 using the Future Land Use Simulation(FLUS)model that couples human and natural effects.Our results show a decrease in productive land(PL)and an increase in ecological land(EL)and living land(LL)in Xining City.Forestry ecological land(FEL)covered the top largest proportion;agriculture productive land(APL)showed the greatest reduction and urban and rural living land(U-RLL)presented a dramatic increase.The eco-environmental quality improved in 1990-2010,mainly affected by the conversion of APL to FEL and GEL.However,the encroachment of U-RLL into APL,other ecological land(OEL)and FEL was the main contributor to the decline in eco-environmental quality in 2010-2015 as well as the primary reason for the increase area of lower-quality.The Harmonious Development(HD)-Scenario,characterized by a rational allocation of LL and PL and a better eco-environment,would have implications for planning and monitoring future management of ELPL,and may represent a valuable reference for local policy-makers.

Spatiotemporal changes of eco-environmental quality based on remote sensing-based ecological index in the Hotan Oasis,Xinjiang

The rapid economic development that the Hotan Oasis in Xinjiang Uygur Autonomous Region,China has undergone in recent years may face some challenges in its ecological environment.Therefore,an analysis of the spatiotemporal changes in ecological environment of the Hotan Oasis is important for its sustainable development.First,we constructed an improved remote sensing-based ecological index(RSEI)in 1990,1995,2000,2005,2010,2015 and 2020 on the Google Earth Engine(GEE)platform and implemented change detection for their spatial distribution.Second,we performed a spatial autocorrelation analysis on RSEI distribution map and used land-use and land-cover change(LUCC)data to analyze the reasons of RSEI changes.Finally,we investigated the applicability of improved RSEI to arid area.The results showed that mean of RSEI rose from 0.41 to 0.50,showing a slight upward trend.During the 30-a period,2.66% of the regions improved significantly,10.74% improved moderately and 32.21% improved slightly,respectively.The global Moran's I were 0.891,0.889,0.847 and 0.777 for 1990,2000,2010 and 2020,respectively,and the local indicators of spatial autocorrelation(LISA)distribution map showed that the high-high cluster was mainly distributed in the central part of the Hotan Oasis,and the low-low cluster was mainly distributed in the outer edge of the oasis.RSEI at the periphery of the oasis changes from low to high with time,with the fragmentation of RSEI distribution within the oasis increasing.Its distribution and changes are predominantly driven by anthropologic factors,including the expansion of artificial oasis into the desert,the replacement of desert ecosystems by farmland ecosystems,and the increase in the distribution of impervious surfaces.The improved RSEI can reflect the eco-environmental quality effectively of the oasis in arid area with relatively high applicability.The high efficiency exhibited with this approach makes it convenient for rapid,high frequency and macroscopic monitoring of eco-environmental quality in study area.

Grey Clustering Evaluation on Regional Eco-environmental Quality Based on Normalized Index Value

[Objective] The aim was to assess regional eco-environmental quality by means of grey clustering method based on normalized index value. [Method] Eco-environmental quality in Chaohu basin was assessed by using grey clustering method based on normalized index value, and the evaluation results were compared with those of unascertained measure method to verify the feasibility of grey clustering method used to evaluate regional eco-environmental quality. [Result] In the grey clustering assessment method based on normalized index value, indices whose standard normalized values in the same grade were close to each other were classified into one class and had the same whitening function, which reduced the number of whitening functions. Grey clustering method based on normalized index value was used to assess eco-environmental quality in Chaohu basin, and the evaluation results were basically in accordance with those of unascertained measure method, namely eco-environmental quality in Hefei, Chaohu and Lu’an belonged to the third (pass), fourth (worse) and fifth grade (bad), except for one grade difference in overall basin, and the results showed that the method had practicality and could be applied to assess regional eco-environmental quality. [Conclusion] The study could provide theoretical foundation for the establishment of comprehensive management countermeasures of regional ecological environment.

Multi-agent Blind Model and Its Application to Regional Eco-environmental Quality Assessment

Through denoting each expert as an agent and viewing a multiple criteria decision-making as a synthesis problem of aggregating experts＇ ratings, a multi-agent blind model （MABM） is developed for regional eco-environmental quality assessment. In this model, the ratings of the evaluated object under an index, given by expert group, are first utilized to construct a series of blind numbers. In general, each index will correspond to different blind numbers. On the basis of aggregating index weights, the rank score in the form of a blind number is obtained for the evaluated object. Then, by means of calculating expected value of the above blind number, its rank score is further converted into a crisp value. By way of comparing the expected value with classification standards, eco-environmental quality of the evaluated sample could he identified successfully in the end. As a case, the MABM is used to evaluate the eco-environmental quality of Chaohu Lake basin. Study result shows that the MABM is a useful model for regional eco-environmental quality assessment.

Universal Index Formula of Parameterized Combination Operator for Eco-environmental Quality Evaluation

[Objective] The aim was to evaluate the regional eco-environmental quality by using the universal index formula of parameterization combination operator based normalized index values.[Method] Through setting reference values and normalized transformation formulae for typical ecological environmental indexes appropriately,the difference among the standard normalized values would become very small after normalized transformation,and the ecological environmental indices expressed by normalized values can be equivalent to normalized indices.Under certain optimization conditions,shuffled frog leaping based on immune evolutionary particle swarm optimization algorithm was applied to optimize the parameters in parameterization combination operator formula,and the universal index formula suited to eco-environmental quality assessment was established finally.[Result] The universal index formula of parameterization combination operator,appropriate for any m(1≤m≤23) ecological environmental indices,was used to assess the eco-environmental quality of towns surrounding Headland Reservoir,and the results were in full accordance with those of unascertained measure method,that is,the eco-environmental quality of five towns around Headland Reservoir was the fourth grade.[Conclusion]The universal index formula of parameterization combination operator,suited to eco-environmental quality evaluation,is simple and intuitive in form,easy in computation and universal in application.

A Geological Classification of Rock Mass Quality and Blast Ability for Widely Spaced Formations

Success in the excavation of geological formations is commonly known as being very important in asserting stability. Furthermore, when the subjected geological formation is rocky and the use of explosives is required, the demands of successful blasting are multiplied. The present paper proposes a classification system, named： BQS （blast ability quality system）, for rock masses with widely spaced discontinuities （spacing longer than l m）. It is obvious that rock quality is one of the main characteristics which define the blast ability of a rock. The BQS can be an easy and widely-used tool as it is a quick evaluator for blast ability and rock mass quality at one time. Taking into consideration the research calculations and the parameters of BQS, what has been at question in this paper is the effect of blast ability in a geological formation with widely spaced discontinuities.

3-D Geological Modeling-Concept,Methods and Key Techniques

3-D geological modeling plays an increasingly important role in Petroleum Geology, Mining Geology and Engineering Geology. The complexity of geological conditions requires different modeling methods in different situations. This paper summarizes the general concept of geological modeling; compares the characteristics of borehole-based modeling, cross-section based modeling and multi- source interactive modeling; analyses key techniques in 3-D geological modeling; and highlights the main difficulties and directions of future studies.

Framework system and research flow of uncertainty in 3D geological structure models

Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions.

Multi-parameter quantitative assessment of 3D geological models for complex fault-block oil reservoirs

In the field of 3 D geologic modeling, researchers often pay more attention to modeling methods and workflows, but neglect the quantitative evaluation of models. If the evaluation is narrowed to the same reservoir type, the comparability and practicality of quantitative assessment will be emerging. The evaluation system should include three parts: data verification, geological understanding and process check. Data verification mainly involves testing the accuracy of local prediction with actual data, and geological understanding is to examine whether the global estimation honors geological principles and prior insights. Process check is also indispensable to avoid occasionality. To this end, we produced a set of assessment criteria, taking complex fault-block sandstone oil reservoir as an example. To be specific, thirteen characteristic parameters were totally selected, setting weights according to their rated importance, formulating three-level evaluation standards in a centesimal system for each characteristic parameter, and obtaining the final assessment based on the cumulative score. The results indicate that such evaluation can not only access the quality of the model objectively and comprehensively, but also identify the aspects in need of improvement through the deduction items.

Determination of blast-induced ground vibration equations for rocks using mechanical and geological properties

In the recent decades, effects of blast loads on natural and man-made structures have gained considerable attention due to increase in threat from various man-made activities. Site-specific empirical relationships for calculation of blast-induced vibration parameters like peak particle velocity （PPV） and peak particle displacement （PPD） are commonly used for estimation of blast loads in design. However, these relation- ships are not able to consider the variation in rock parameters and uncertainty of in situ conditions. In this paper, a total of 1089 published blast data of various researchers in different rock sites have been collected and used to propose generalized empirical model for PPV by considering the effects of rock parameters like unit weight, rock quality designation （ROD）, geological strength index （GSI）, and uniaxial compressive strength （UCS）. The proposed PPV model has a good correlation coefficient and hence it can be directly used in prediction of blast-induced vibrations in rocks. Standard errors and coefficient of correlations of the predicted blast-induced vibration parameters are obtained with respect to the observed field data. The proposed empirical model for PPV has also been compared with the empirical models available for blast vibrations predictions given by other researchers and found to be in good agreement with specific cases.

A STUDY ON ECONOMY EVALUATION ON THE PROFIT AND LOSS OF GEOLOGIC ENVIRONMENTAL QUALITY ABOUT GEOLOGIC ENVIRONMENTAL EXPLOITATION PROJECT

The problems of environmental geology refer to the geologic phenomena, incidents or accidents arising from action of environmental geology. The action is mainly the mutual influence between human activity and geologic environment. When human activity is uncoordinated with objective laws of the geologic environment, the problems of environmental geology or economic loss would occur.Therefore,the level and the changing orientation of geologic environmental quality are relative to the types of human activity,particularly relative to human intentional-activities of geologic environmental exploitation project. The geologic environment fitting to mining may not fit to urban construction,and fitting to water conservancy and hydroelectric projects may not fit to communication,and so on.Economy evaluation on the profit and loss of geologic environmental quality is exactly to depict the level of the profit and loss of geologic environmental quality about geologic environmental exploitation projects and the

Groundwater Quality Assessment in Pul-e-Charkhi Region,Kabul,Afghanistan

We present the results of studies conducted on the assessment of groundwater quality observed on several water samples taken from water supply sources in the Pul-e-Charkhi region,which is located near the eastern part of Kabul and has seen steady growth in population after the U.S.completed its withdrawal from Afghanistan on 30 August 2021.The water in the basin serves as the main source of water supply and it consists of water discharge from nearby local industries,automobile repair and wash,Osman House,Gradation Place,International Standards Region,and many other regional sources that create a mix of contaminants in discharge to the basin.We collected several samples from each groundwater source for this investigation and transported them carefully to the research laboratory,maintaining the integrity of the samples.The main objective of this study is to assess groundwater quality for the determination of contaminants in groundwater to see what limitations it may pose for recycling and reuse.Such a study is necessary since the region requires persistent sources of water due to a steady increase in population and an associated shortage of water supply due to arid conditions.Furthermore,there is unavailability of similar data since the region served to support military operations since 2001.The samples were analyzed for temperature,electro-conductivity,dissolved oxygen,total dissolved solids,salinity,pH,color,turbidity,hardness,chemicals,and heavy metals.The results obtained suggest that the parameters can be used efficiently to design filtration strategies based on region-specific contamination for the specific catchments located in and around the Kabul Basin.An effort to add additional characterization techniques is described to detect micro/nano plastics and new and emerging contaminants.The efforts reported here are consistent with the 2030 agenda for Sustainable Development Goals.

基于AHP的海峡沿岸地区生态地质环境质量评价——以马六甲海峡北岸马来西亚西南沿海地区为例

生态地质环境质量显示一个区域地质作用与生态空间分布的整体情况。为了给马六甲海峡北岸马来西亚西南沿海地区的生态保护修复及“一带一路”投资建设提供依据,将地理信息系统技术与层次分析法相结合,以马来西亚基础地质、地质灾害遥感地质专题应用及编图项目成果数据集为基础数据,构建了该区的生态地质环境质量评价指标体系并进行综合评价。通过分析结果将研究区的生态地质环境质量划分为优等、良好、中等、较差4个等级,其中:优等区和良好区面积较大,分别为2 753.31 km^(2)和2 960.33 km^(2),占研究区总面积的34.19%和36.76%,主要分布在北部平原地区及沿海地区;中等区和较差区面积分别为1 702.72 km^(2)和618.57 km^(2),占研究区总面积的21.37%和7.68%,主要分布在雪兰莪州中部、森美兰州南部及马六甲州北部地区。从评价结果上看,该地区总体上生态地质环境质量较好,优等区和良好区总和占研究区总面积的70.00%以上,中等区和较差区主要受地层构造和生态条件的限制,需要针对具体问题进行环境保护及生态修复。

长江中下游地区流域生态资产价值评估——以新安江流域为例

【研究目的】生态资产评估有助于理清区域生态资源本底,为建立健全自然资源监管技术体系,实施生态补偿政策提供科学依据,对于推动生态产品价值实现具有重要意义。【研究方法】本文构建了生态资产价值评估的方法指标体系,通过集成土地利用、遥感影像、气象、地球化学以及社会经济等多源数据,开展生态资产存量、生态资产质量以及生态资产价值评估,并结合地理探测器探求生态系统服务价值的空间分异影响因素。【研究结果】2020年新安江流域生态资产质量等级以良、中为主,分别占比80.96%、10.25%;生态资产存量综合指数为0.77,湿地、森林与园地占主要位置;流域生态系统服务价值为1334.48亿元,森林资源与水资源价值占比最高,坡度、高程和年降水量为影响生态系统服务价值空间分异的主要驱动因子。【结论】新安江流域生态资产价值较高,森林与水资源是流域生态系统服务的主要载体,自然禀赋条件对其生态系统服务价值空间分异的影响程度大于社会经济因素。

国外地质勘查与资源调查评价中样品分析质量保证与质量控制的实践

文章总结了质量保证与质量控制(Quality Assurance/Quality Control, QA/QC)在地质勘查和资源调查评价样品分析中的意义,根据最佳工业实践,推荐质控样品的插入率≥20%。对质控样品的选择与评价方法进行总结,标准样品应与待测样品基体匹配且含量范围涵盖整个待测样品的含量水平,标准样品的测试结果使用控制图进行准确度判断;重复样品应在每一个重要的采样、制样阶段进行采集,并且应随机选取,重复样品的分析结果通过散点图判断精密度是否达到预期设定界限,通过相对偏差图可以获得不同因素对精密度的影响,国际上通用的量化重复样品精密度的方法是计算变异系数(Coefficient of Variation, CV);空白样品的目标元素含量应低于检出限,实验室空白样品一般为高纯度的石英砂,实际的资源勘查项目中也可采集野外空白样品进行污染监控,空白样品的控制限为3~5倍方法检出限;外检样品应送到级别相当或更高的实验室进行检测,判断两个实验室测量结果的差异,外检样品选择应随机,通过散点图判断外检样品结果的可靠性。文章通过国际上资源调查评价中质量控制与质量保证的实例进行总结,与国际标准对标,对于今后海外找矿,海外资源调查评价有重要作用。