Assessment on eco-environmental quality of the Yellow River Basin by considering desertification index

Desertification has had a significant impact on the ecological environment of the Yellow River Basin(YRB)in China.However,previous studies on the evaluation of the ecological environment quality(EEQ)in the YRB have paid limited attention to the indicator of desertification.It is of great significance to incorporate the desertification index into the spatiotemporal assessment of the EEQ in the YRB in order to protect the ecological environment in the region.In this study,based on multi-source remote sensing data from 91 cities in the YRB,this article proposes a desertification remote sensing ecological index(DRSEI)model,which builds upon the traditional Remote Sensing Ecological Index(RSEI)model,to analyze the spatiotemporal changes in the EEQ in the YRB from 2001 to 2021.Furthermore,using the geographic detector(GD),and geographically and temporally weighted regression(GTWR)model,the study assesses the impact of human and natural factors on the EEQ in the YRB.The research findings indicate that:(1)Compared to the traditional RSEI,the improved DRSEI shows a decreasing trend in the evaluation results of the EEQ.Among the 24 cities,the change in DRSEI exceeds 0.05 compared to RSEI,accounting for 26.37%of the YRB.The remaining 67 cities have changes within a range of less than 0.05,accounting for 73.63%of the YRB.(2)The results of the GD for individual and interactive effects reveal that rainfall and elevation have significant individual and interactive effects on the EEQ.Furthermore,after the interaction with natural factors,the explanatory power of human factors gradually increases over time.The spatial heterogeneity results of GTWR demonstrate that rainfall has a strong direct positive impact on the EEQ,accounting for 98.90%of the influence,while temperature exhibits a more pronounced direct inhibitory effect,accounting for 76.92%of the influence.Human activities have a strong negative impact on the EEQ and a weak positive impact.

EARTHQUAKE FOCAL MECHANISM AND ITS TECTONIC SIGNIFICANCE ALONG THE TWO SIDES OF THE RED RIVER FAULT ZONE

The Red River Fault Zone is a gigantic slide-slip fault zone extending up to 1000km from Tibet to SouthChina Sea. It has been divided into the north, central and south segments according to the difference of thegeometry, kinetics, and seismicity on the land, but according to the contacted relationship between the old pre-Cenozoic block in Indochina Peninsula and the South China block, the Red River Fault Zone was divided into two parts extending from land to ocean, the north and south segments. Since the Tertiary, the Red River Fault Zone suffered first the sinistral movement and then the dextral movement. The activities of the north and the south segments were different. Based on the analysis of earthquakes and focal mechanism solutions,earthquakes with the focus depths of 0-33km are distributed over the whole region and more deep earthquakes are distributed on the northeastern sides of the Red River fault. Types of faulting activities are the thrust in the northwest, the normal in the north and the strike-slip in the south, with the odd type, viz. the transition type, in the other region. These show the Red River Fault Zone and its adjacent region suffered the extruding force in NNW direction and the normal stress in NEE direction and it makes the fault in the region extrude-thrust,horizontal strike-slip and extensional normal movement.

Analysis on the Influencing Factors of Residents' WTP for Environmental Protection in Tourist Destination——A Case Study of Yellow River Stone Forest in Jingtai of Gusu Province

On the basis of questionnaire survey,by adopting Contingent Valuation Method,residents' WTP for the protection of Yellow River Hoodoo National Geopark in Longwan Village,Jingtai County of Gansu Province was investigated.The result showed that tourism development had greatly influenced local society,economy and culture.Residents in this area had a strong awareness of all the factors above mentioned and showed a positive attitude.Local residents would definitely like to provide a certain degree of labor or money to promote the development of tourism,which was different from the residents' attitude of developed countries.To some extent,it reflected the characteristics of tourism development in developing countries.However,the result of this paper that demographic among residents had little effect on WTP also differed from previous researches.The improvement of living standard and residents' consciousness of environmental protection were the main reasons affecting residents' WTP.Besides,the amount of payment was also in remarkable correlation with the improvement of living standard and the destruction degree of local ecological environment.

Creation of "Regional Characteristic" in Planning and Design of Farmers' Residential Area at the South of Lower Reaches of the Yangtze River

After analysis of location feature of the south of lower reaches of Yangtze River and its construction of urban and rural integration,the paper pointed out harmonious combination between natural and artificial factors had been neglected in planning and design of farmers' residential area at the south of lower reaches of Yangtze River,"regional characteristic" losing,residential area in the form of "city community" and buildings in European style.In view of these problems,relevant planning and design thoughts and methods had been proposed as to how to create "regional characteristic" from the perspective of planning,architecture and landscape design.It discussed with emphasis the importance of construction base type and combination of environment with residential area construction;inspirations and design methods obtained from traditional architectures;and the content of landscape overall planning and specific design.It was hoped to enlighten designers to shoulder social and historical responsibility,make exploration unremittingly,and construct beautiful homelands for people.

Residents’ perspectives and responses to environmental degradation in the upper Dadu River, eastern Tibetan Plateau

Environmental degeneration in the Tibetan Plateau attracts worldwide attention, whereas case studies on how the residents understand and respond to environmental degeneration are scarce. Using a Participatory Rural Appraisal method, this paper investigates how the people in different regions in the upper Dadu River understand and respond to environmental degeneration, based on comparative field surveys in three villages, in which Danzamu village is chosen from villages in the valley region, Kerma village from mountainside region, Rico village from the mountain and plateau region. The results show that： （1） although awakened to environmental degeneration, the residents in different regions have different responses. As agricultural labors have been transferred to the secondary and tertiary industries, population pressure in Danzamu and Kerma villages is mitigated. Residents in Danzamu village actively respond to natural disasters and forest degradation, as their livelihoods never rely on forests and rangelands again. Whereas the residents in Kerma village negatively respond to natural disasters, forest and meadow degradation and the ruin of wildlife resources, as their livelihoods still rely on stockbreeding. Labors in Rico village are hard to transfer to the secondary and tertiary industries, so they have to raise more livestock to make a living. Active measures are just taken to avoid livestock loss, not to avoid forest and meadow degradation and the ruin of wildlife resources. So the most fragile region is the mountain and plateau region and mountainside region, not the valley region. （2） Livelihood strategy is the key factor affecting the residents to respond to population pressure and environmental degeneration. So the framework of sustainable livelihood strategy should be used to explain and intervene in issues of population pressure and environmental degradation in ecotones. （3） Transferring agricultural labors to the secondary and tertiary industries were favorable to improving people＇s livelihood. It is necessary to reduce the education fees to speed up the pace of labors transferring in the mountainside region. In the mountain and plateau region, preferable ways also include the development of towns, highways, education equipment and other establishments.

Controlling floor heave of extraction opening by reinforcing sides and roof

The effect of reinforcing roof, sides and floor corners to control floor heave of extraction opening was analyzed, It was proved by engineering practice and numerical simulation that reinforcing any part of surrounding rock have certainly control effect for floor heave, in the basis of this, the new way that roof, sides and floor corners were rein-forced to control floor heave was put forward. Contrasting control result of reinforcing floor with this, it is determined that reinforcing is more suitable to control floor heave of extrac-tion opening than reinforcing floor when advancing abutment pressure is in some range.

Estimation of Water Environmental Capacity Considering Hydraulic Project Operation in the Xiangyang Reach of the Han River, Central China

Using the Xiangyang Reach of the Han River as an example, this paper evaluates the changes of water environmental capacity after the implementation of Cuijiaying Hydro-junction project. The allowable pollutant loads entering the Xiangyang Reach were estimated using two-dimensional steady state water quality model with different data sets. The water environmental capacity has declined in the reservoir area of the Cuijiaying Hydro-junction project during the low-flow period;it is appearing to increase slightly in the upper and lower stream of this reservoir. However, the state of flow may turn into the state of reservoirs flow in the reservoir area, and the changes of hydrological regime may cause the water flow and the nutrient contents suitable for the occurrence of ecological environment problems.

Characteristics and Optimization of Distribution of Rural Residential Area in Wangcun River Basin of Linfen City

As a carrier of rural population,rural residential area carries important functions such as rural production and life. This paper studied the characteristics of rural residential area and optimization model,to lay certain foundation for integrating urban and rural development and increasing economic income. With the aid of Arc GIS 10. 1 and Fragstats 3. 4 software,based on the theory of landscape ecology,it analyzed the distribution characteristics of residential area in Wangcun River Basin of Anze County,Linrfen City,Shanxi Province. Besides,according to distribution characteristics,it analyzed three optimization models: priority development model,retention limit development model,and migration development model.

Mississippi River Delta: Land Subsidence and Coastal Erosion

The Mississippi River Delta is a major center for transportation, industry, human population and ecosystem services. Critical areas included energy production, navigation, fisheries, flood protection of coastal communities, and restoration of damaged habitats. Complex environmental management in a great river system requires broad-base complex science, engineering and monitoring. A major national and state objective has become the restoration of the Mississippi River Delta that is threatened by subsidence, flooding, storm surges, compaction, oil extraction and gas extraction. The primary objectives of the paper are to document the landscape and geological properties of the Mississippi River Delta which have contributed to the successful resource and economic development of a historically-rich region of North America and to document the natural resource and environmental risks to the Mississippi River Delta. Economic and urban development of the Mississippi River Delta by the oil and gas industry and creation of levees by the USACE has contributed to land subsidence problems. Environmental challenges include land subsidence as a result of the pumping of vast amounts of oil and gas, the lack of sediment deposition in the Mississippi River Delta as a result of a system of levees, coastal erosion impacts of hurricanes, disposal of untreated and treated wastewater, periodic flooding and water pollution.

Strength and deformation behavior of the Yellow River silt under triaxial drained condition considering characteristic states

Currently,the application of the Yellow River silt in subgrade,especially in expressway subgrade,has not been widely promoted.The main reason is that the research on the mechanical characteristics of the Yellow River silt used for subgrade filling is extremely limited.In this study,the static shear test of the Yellow River silt under drained condition was carried out using Global Digital Systems(GDS)triaxial apparatus,and the effects of confining pressure,relative density and shear rate on the strength and deformation behavior of the Yellow River silt were investigated.The cohesive force of the Yellow River silt is low,and the friction angle is the main factor determining the shear strength.Friction angle at phase transformation stateφpt,friction angle at peak stateφps,friction angle at critical stateφcs,were obtained via the observation on the evolution law of mobilized friction angle during the whole shearing process.The friction angles corresponding to three different characteristic states have the following magnitude relationship,namelyφps>φcs>φpt.The strength parameters for low-grade subgrade and highgrade subgrade were chosen to be 29.33°and 33.75°.The critical state line(CSL),envelop of phase transformation(EOP),and envelop of dilatancy(EOD)for three different characteristic states were determined.The critical stress ratio M,the phase transformation stress ratio Mptand the dilatancy stress ratio Mdof the Yellow River silt are 1.199,1.235,1.152,respectively.These results provide a basis for the mechanical analysis of the Yellow River silt subgrades and the subsequent establishment of dynamic constitutive model of the Yellow River silt.

Living environment shaped residents’willingness to pay for ecosystem services in Yangtze River Middle Reaches Megalopolis,China

Profound understanding on the diversity of local residents’willingness to pay(WTP)for ecosystem services(ESs)may aid evaluation of policy impacts by uncovering trade-offs and synergies for achieving sustainable environmental resource management.However,the reasons for the spatial preference heterogeneity of WTP are still unclear.In this study,an extensive survey with 4,580 residents in the Yangtze River Middle Reaches Megalopolis(YRMRM),central China,was carried out to investigate the public’s WTP to maintain and improve ESs.We identified key influencing factors and explored how they shaped the preference heterogeneity in WTP by random forest model and surface fitting method.Our results showed that 81.4% of residents reported WTP for ESs greater than zero.Water supply,waste treatment,food supply and raw material supply were the preferred ESs for residents.Living environment factors(i.e.,extent of farmland,water and forest near the residence)were found as the key drivers of WTP.Proximity to farmland,water and forests resulted in high WTP values for a series of specific ESs.The reasons for the heterogeneity of WTP are(1)the difference in proximity to farmland,water and forest(i.e.,the contributor to ESs),(2)the divergence of local residents’preferences for ESs.This study disclosed the heterogeneity and causes of public preferences in YRMRM,which could help policy and decision makers to develop eco-compensation initiatives towards conservative and sustainable use of the environmental resources.

Class of numerical methods for differential-algebraic systems with discontinuous right-hand sides

Numerical methods for Differential-Algebraic systems with discontinuous right-hand sides is discussed. A class of continuous Rosenbrock methods are constructed, and numerical experiments show that the continuous Rosenbrock methods are effective. Applying the methods, a fast and high-precision numerical algorithm is given to deal with typical discontinuous parts, which occur frequently in differential-algebraic systems(DAS).

Residential building thermal performance energy efficiency in Yangtze River basin

Using energy consumption software VisualDOE4.0,simulation was carried out on the energy consumption of a typical residential building in Yangtze River basin,with a focus on thermal performance of envelope each component and application of total heating recovery equipment. The effects of thermal performance of building envelope each component on energy efficiency ratio were analyzed. Comprehensive measures schemes of energy saving were designed by the orthogonal experiment. The energy efficiency ratios of different envelopes combination schemes were gained. Finally,the optimize combination scheme was confirmed. With the measurement dates,the correctness of the simulation dates was completely verified.

Analysis of the sensory threshold between paretic and nonparetic sides for healthy rehabilitation in hemiplegic patients after stroke

The purpose of this study was to investigate the differences in the sensory threshold between the paretic and nonparetic sides of hemiplegic patients. 28 patients who were hemiplegic post-stroke (14 men and 14 women) participated in the electrical sensory and pain thresholds study;22 patients who were hemiplegic post-stroke (13 men, 9 women) participated in a study measureing the sensory threshold with light touch. Electrical sensory and pain thresholds were measured in the forearm via transcutaneous electrical nerve stimulation. The light-touch threshold was measured in the forearm using monofilaments. The light-touch, electrical sensory, and pain thresholds for the paretic side were significantly higher than for the nonparetic side in our population, respectively. In both the nonparetic and paretic sides, the male group generally showed higher thresholds for pain and sensation than did the female group. These results suggest that the different evaluations of sensory thresholds performed in this study for healthy rehabilitation will be a valuable clinical tool in hemiplegic patients after stroke.

Applied analysis of ventilation technology in residential buildings in Changjiang river valley

Making the use of ventilation technology may decrease building energy consumption,improve indoor thermal environment,and ameliorate indoor air quality. Combining with the meteorological characteristics in the Changjiang river valley and focusing on Chongqing,this work makes an applied analysis of the feasibility of intermittent mechanical ventilation. By comparison of various ventilation modes,it gives a summary of the suitable ventilation ways for different weather conditions with the combination of testing data and experimental data.

Quantitative Analysis of Groundwater Flow near a Partially Penetrating River under Riverside Pumping

According to practical geological and hydrogeological conditions of riverside water-supply well fields in northwestern China, an ideal hydrogeological model has been generalized and a three-dimensional mathematical model has been set up. A finite difference method was applied to simulating groundwater flow near a partially penetrating river under riverside pumping, and to analyzing the effects of river width, partial penetration and permeability of riverbed sediments on groundwater recharges. Results show that riverside pumping may cause groundwater to flow beneath the partially penetrating river, and that river width, penetration and riverbed permeability obviously influence flows from the partially penetrating river and constant-head boundaries. However, the pumping output is mainly from the partially penetrating river.

基于River 2D模型的黄河花园口河段生态流量研究

针对目前生态流量研究方法难以充分考虑鱼类栖息地等生境因素的问题,以黄河花园口鲤鱼核心保护区为研究区域,选取黄河鲤鱼为研究物种,基于耦合水动力学模型和栖息地模型的River 2D模型确定黄河鲤鱼的生态流量,将水深和流速作为鱼类生存保护的限定性因子,采用栖息地模型模拟不同流量下对应的黄河鲤鱼的适宜栖息地面积。计算结果表明:花园口河段鲤鱼产卵期的最小生态流量为230 m^(3)/s,生长期的最小生态流量为430 m^(3)/s,越冬期的最小生态流量为150 m^(3)/s。计算结果可以为花园口核心鱼类保护区的鱼类保护以及黄河小浪底水库的生态调度提供参考。

Physical Profile of the Major Rivers in Eastern Samar inside the Samar Island Natural Park (SINP)

The study was conducted to illustrate the physical profile of the three major rivers of Eastern Samar inside the SINP to serve as a reference for the river landscape. Highlights of the profile are river width, depth, water velocity and water flow rate, potential source, river stretch, flood height and flood plain as inputs to development and disaster planning. Data presented here were based on field surveys supported and guided by reference maps. Based on the survey, a potential source of Oras and Ulot-Can-avid Rivers is San Jose de Buan, Samar while Suribao River flows from the closed-canopy forest from Borongan-Maydolong-Llorente (Eastern Samar). Flooding and erosion were observed in the three rivers, but the highest silt deposits and the widest flood plain were in Oras River, with the highest water flow rate in the upstream. Erosion and quarrying were observed in all rivers. Bamboo reforestation is conducted in Suribao River as river bank erosion control measures. Results of the survey revealed the high risk to our rivers and river villagers due to flooding and erosion, in addition to the loss of properties and livelihood, and the ecological conservation of the landscape. Collective rehabilitation measures should be crafted for a unified action to address environmental issues parallel to development plans to promote but sustainably manage our resources and protect our villagers.

Study on mechanism of reinforcing sides to control floor heave of extraction opening

Roadway surrounding rock is a compound structure consisted of roof, floor and sides. The sides of extraction opening is the weak coal mass, which affect immediately the stability of floor. It was simulated by numerical calculation for the strength of sides coal to affect the floor heave, the higher strength of sides coal is, the lower degree of floor heave was. So it was put forward reinforcing sides to control floor heave of extraction opening, and it was proved by engineering practice that the floor heave of deep extraction opening can be controlled to a certain degree by reinforcing sides of roadway.

Land Cover Change and Its Socio-Economic Impact on the Residents of the Mara River, Kenya

Anthropogenic activities are increasingly catalyzing natural climatic factors that drive land cover change at different spatial scales. Available land cover data of the Mara River basin however give a broader picture of the entire basin regardless of the heterogeneity that exists at the sub-catchment level. This study sought to establish sub-catchment specific information on land cover changes through examination of satellite images of four Mara River sub-catchments (Amala, Nyangores, Talek and Sand River) for the period 1987-2017. The relationship between temperature, rainfall and land cover was also computed. In addition, a household survey and focus group discussions were conducted in each sub-catchments to establish the socio-economic impacts of land cover change on the community’s wellbeing. Forest cover was dominant in Amala (39.8%) and Nyangores (43.7%) sub-catchments in 1987 but by 2017 crop lands had surpassed forest cover in the two sub-catchments, accounting for 53.2% and 45.7%, respectively. However, in Talek (52.8%) and Sand River (47.4%) sub-catchments, grassland was the dominant land cover type in 1987 and after the 30 year period, grasslands remained dominant in Sand River, while shrub land became dominant in Talek sub-catchment. A weak positive correlation was observed between rainfall and forest cover, shrub land and cropland, while a negative correlation was observed between rainfall and bare land. Average temperature showed a positive moderate correlation with bare land and built up areas. Analysis of survey data revealed that livestock keeping, temperature increase, type of trees, education level of household head and weak environmental laws were the main drivers of land cover change (P −0.587), beans (r = −0.5459), sorghum (r = −0.351), cow peas (r = −0.544), and pigeon peas (r = −0.337). Focus group discussions participants were supportive of environmental protective measures to reverse negative land cover changes, while planting drought resistant trees, crop diversification and awareness creation among community members were recommended as the most ideal environmental management strategies.