Epidemiology of Low Birth Weight in the Lake Areas of Cotonou (Benin Republic)

Introduction: Low birth weight is a significant public health problem worldwide, particularly in low-and-middle-income countries. This study aimed to investigate the epidemiology of low birth weight in the lake areas of Cotonou. Methods: A cross-sectional analytical study included 931 records of women who gave birth in 2022 in the Cotonou 1-4 health zone. Completed maternity records were included in this study, except for premature births and congenital malformations. Birth weight was the dependent variable. Sociodemographic, obstetrical, preventive care and child-related data were collected using a digitized form. These data were analyzed using SPSS software to determine the prevalence and factors associated with low birth weight using multiple logistic regression analysis. Results: The prevalence of low birth weight was 16.30%. Factors related to this prevalence were non-use of mosquito nets during pregnancy (OR = 2.72;CI: 1.275 - 5.805), twin pregnancy (OR = 9.97;CI: 3.869 - 25.696), previous abortion (OR = 1.61;CI: 1.034 - 2.515), low number of pregnancy (OR = 3.97;CI: 1.276 - 12.393), trimester of first antenatal visit (OR = 3.47;CI: 1.821 - 6.638) and birth size less than 45 cm (OR = 5.98;CI: 2.965 - 12.083). Conclusion: The prevalence obtained from this study justifies the need to support pregnant women in this health zone. It is, therefore, essential to strengthen communication and health promotion strategies for women before, during, and after pregnancy.

Epidemiology of Low Birth Weight in the Lake Areas of Cotonou (Benin Republic)

Introduction: Low birth weight is a significant public health problem worldwide, particularly in low-and-middle-income countries. This study aimed to investigate the epidemiology of low birth weight in the lake areas of Cotonou. Methods: A cross-sectional analytical study included 931 records of women who gave birth in 2022 in the Cotonou 1-4 health zone. Completed maternity records were included in this study, except for premature births and congenital malformations. Birth weight was the dependent variable. Sociodemographic, obstetrical, preventive care and child-related data were collected using a digitized form. These data were analyzed using SPSS software to determine the prevalence and factors associated with low birth weight using multiple logistic regression analysis. Results: The prevalence of low birth weight was 16.30%. Factors related to this prevalence were non-use of mosquito nets during pregnancy (OR = 2.72;CI: 1.275 - 5.805), twin pregnancy (OR = 9.97;CI: 3.869 - 25.696), previous abortion (OR = 1.61;CI: 1.034 - 2.515), low number of pregnancy (OR = 3.97;CI: 1.276 - 12.393), trimester of first antenatal visit (OR = 3.47;CI: 1.821 - 6.638) and birth size less than 45 cm (OR = 5.98;CI: 2.965 - 12.083). Conclusion: The prevalence obtained from this study justifies the need to support pregnant women in this health zone. It is, therefore, essential to strengthen communication and health promotion strategies for women before, during, and after pregnancy.

Analysis to the Driving Force Model and Drives Factor on the Utilized Changes of Cultivated Land in Qinghai Lake Area

Using path analysis, correlation analysis, partial correlation analysis and system dynamics method to study the driving force of cultivated land in Qinghai Lake Area, and using gradually regression analysis to establish the driving force model of utilized change of cultivated land. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed, and the differences during all factors were compared. The study provides some decision basis for sustainable utilization and management of land resources in Qinghai Lake Area.

Eco-compensation effects of the wetland recovery in Dongting Lake area

Eco-compensation is an environmental economic instrument for internalization of external cost. Returning farmland to lake is one of the important parts of restoring wetland ecosystem function in the Yangtze River Valley of China. Whether the project of lake recovery can be successful depends on the compensation to the farmers who have lost their original benefits and contributed to the wetland ecosystem recovery by returning farmland to lake. Aiming at the wetland recovery of the Dongting Lake, the practical implementation of pro- grams of the lake recovery and flood control in this area has been challenged by the heavy task of population resettlement, so it is an ideal area for case studies to reach the academic objectives proposed as the above. Based on field survey and experimentation, this research evaluated the benefit losses of the resettled farmers and the increased values of ecosystem service functions caused by wetland recovery, and furthermore, the value of eco-compensation for relocated farmers was calculated by considering the combination of the farmers＇ compensation appeal. The value of eco-compensation for relocated farmers in the Dongting Lake area was 6084.5 yuan per household by synthetic analysis of the effects on wetland ecosystem restoration. Moreover, this article took Dongting Lake area as a case to study and explore the basic issues of the eco-compensation by returning farmland to lake, that was who should pay, who should be paid, how much the payment was and what the payment means was, which sought the mechanisms of wetland restoration eco-compensation and prompted the people＇s enthusiasms for ecological restoration.

Discussion on the Green Tax Stimulation Measure of Nitrogen Fertilizer Non-Point Source Pollution Control-Taking the Dongting Lake Area in China as a Case

A study on designing the tax of nitrogen fertilizer can provide a new method for controlling nitrogen fertilizer non-point source pollution. The tax design of nitrogen fertilizer was discussed by utilizing the external theory and the demand elasticity theory. The results indicated that the coefficient of price elasticity of nitrogen fertilizer demand is -0.21, which instructed that the market demand is in lack of elasticity in the short period and the impact of nitrogen fertilizer manufacturers is subtle. The 11 counties （cities and boroughs） in the Dongting Lake area in China, where the farmland nitrogen application surpassed the average ecological fertilization dosage, is listed to the taxation scope of nitrogen fertilizer tax. The environment loss will reduce 0.07 hundred million RMB yuan and the revenue will increase 0.89 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The loss, which was brought by the decreasing food supplies production, will be 0.58 hundred million RMB yuan and the net social benefit will be 0.38 hundred million RMB yuan following revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.49%. The variation scope of the income of farmers will range from -8.41 to 6.44%. The 5 areas, Yunxi Borough, Junshan Borough, Hanshou County, Jinshi City, and Ziyang Borough, had an increase in food supplies production after the revenue collection. The environment loss will reduce 0.01 hundred million RMB yuan and the revenue will increase 0.16 hundred million RMB yuan in the country after levying on nitrogen fertilizer. The economic benefits, which was brought by the increasing cereals production, will be 0.67 hundred million RMB yuan and the net social benefit will be 0.84 hundred million RMB yuan after revenue collection. The variation scope of the increasing expenditure of farmers will range from 0.95 to 1.06%. The variation scope of the increasing income of farmers will range from 0.69 to 6.44%. Considering the entire social welfare, taxation of nitrogen fertilizer will have more advantages than disadvantages in the Dongting Lake area.

The spatial-temporal changes of the land use/cover in the Dongting Lake area during the last decade

The research on the land use/cover change is one of the frontiers and the hot spots in the global change research. Based on the Chinese resource and environment spatial-temporal database, and using the Landsat TM and ETM data of 1990 and 2000 respectively, we analyzed the spatial-temporal characteristics of land use/cover changes in the Dongting Lake area during the last decade. The result shows that during the last ten years there were three land-use types that had changed remarkably. The cultivated land decreased by 0.57% of the total cultivated land. The built-up land and water area expanded, with an increase of 8.97% and 0.43% respectively. The conversion between land use types mostly happened among these three land-use types, especially frequently between cultivated land and water area. The land-use change speed of land-use type is different. Three cities experienced the greatest degree of land-use change among all the administrative districts, which means that the land use in these cities changed much quickly. The following changed area was the west and south of the Dongting Lake area. The slowest changed area is the north and east area.

Characterizing regional precipitation-driven lake area change in Mongolia

Lake area is an important indicator for climate change and its relationship with climatic factors is critical for understanding the mechanisms that control lake level changes. In this study, lake area changes and their rela- tions to precipitation were investigated using multi-temporal Landsat Thermatic Mapper （TM） and Enhanced Thermatic Mapper plus （ETM＋） images collected from 10 different regions of Mongolia since the late 1980s. A lin- ear-regression analysis was applied to examine the relationship between precipitation and lake area change for each region and across different regions of Mongolia. The relationships were interpreted in terms of regional climate regime and hydromorphological characteristics. A total of 165 lakes with areas greater than 10 hm2 were identified from the Landsat images, which were aggregated for each region to estimate the regional lake area. Temporal lake area variability was larger in the Gobi regions, where small lakes are densely distributed. The regression analyses indicated that the regional patterns of precipitation-driven lake area changes varied considerably （R2=0.028-0.950）, depending on regional climate regime and hydromorphological characteristics. Generally, the lake area change in the hot-and-dry Gobi regions showed higher correlations with precipitation change. The precedent two-month pre- cipitation was the best determining factor of lake area change across Mongolia. Our results indicate the usefulness of regression analysis based on satellite-derived multi-temporal lake area data to identify regions where factors other than precipitation might play important roles in determining lake area change.

External Costs and Optimum Use of Nitrogen Fertilizer Based on the Balance of Economic and Ecological Benefits in the Paddy Field System of the Dongting Lake Area, China

The external costs and the optimum use of nitrogen fertilizer based on the balance of economic and ecological benefits was studied with the paddy field system of Dongting Lake area, one of the main food production regions in China. The environmental impact was economically evaluated using methods of the environmental impact economical evaluation. The optimum use of nitrogen fertilizer was calculated based on the exterior diseconomy theory and by using the production function model. Both ecological benefits and farmers＇ economic benefits were considered. It was calculated on the data from 2002 that the losses caused by inappropriate utilization of nitrogen fertilizer in the process of food production were fishery, 0.1 × 10^7 RMB yuan; water treatment, 1.02 × 10^8 RMB yuan; tour business, 0.11 ×10^8 RMB yuan, and habitation environment, 0.3 × 10^7 RMB yuan, totally equivalent to 0.41 RMB yuan kg^-1 N. The economically satisfactory and the ecological agronomic nitrogen fertilizer dose for current production was 138 and 137 kg ha^-1, respectively. The research showed that the actual nitrogen fertilizer application amount in the paddy field system of the Dongting Lake area already reached or exceeded the farmers＇ economic satisfaction and the ecological agronomic nitrogen fertilizer dose for current production. An environmental tax is suggested to impose on over-use of nitrogen fertilizer.

Study on the Resistance Indexes of Four Kinds of Desert Plants in Qinghai Lake Area

[Objective] The research aimed to study the resistance of four kinds of desert plants in Qinhai Lake area.[Method] By contrasting the resistance indexes of four kinds of plants which included Ephedra intermedia,Stellera chamaejasme,Achnatherum splendens and Xanthopappus subacaulis,the resistance of four kinds of plants in Qinghai Lake area was analyzed.The resistance indexes included the soluble protein,MDA,free Pro content and the activities of SOD,POD,CAT.Moreover,the resistance of four kinds of plants was evaluated comprehensively by using Fuzzy membership function method.[Result] Under the low-temperature and arid adversity in Qinghai Lake area,SOD activity presented as Stellera chamaejasme>Xanthopappus subacaulis>Ephedra intermedia>Achnatherum splendens,and CAT activity presented as Stellera chamaejasme>Xanthopappus subacaulis>Achnatherum splendens>Ephedra intermedia.Under the same high-salt environment,CAT activity of Stellera chamaejasme was eight times higher than that of Ephedra intermedia.It illustrated that the salt resistance of Stellera chamaejasme was stronger than that of Ephedra intermedia.The free Pro content showed as Xanthopappus subacaulis>Ephedra intermedia>Stellera chamaejasme>Achnatherum splendens.Under the same adversity,Pro content of Ephedra intermedia was 2.83 times of Stellera chamaejasme.It was because that MDA content in Stellera chamaejasme was the lowest,and the membranous peroxide harm was the smallest.It caused that Pro content (stress penetration material) was low.It also illustrated that the resistance of Stellera chamaejasme was stronger than that of Ephedra intermedia.The comprehensive evaluation of Fuzzy membership function showed that the resistance presented as Xanthopappus subacaulis>Stellera chamaejasme>Ephedra intermedia>Achnatherum splendens.[Conclusion] The research provided the theory basis for the breeding of drought-resistance new variety and the development of good germ plasm resource in Qinghai Lake area.

A multi-scale 3-D crust velocity model in the Hefei-Chao Lake area around the southern segment of Tanlu Fault Zone

Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the main geological units of Hefei Basin,with thick sediments and the Chao Lake depression.Several major concealed faults of the southern NNE-trending Tanlu Fault Zone cross this area.To further explore the underground distribution characteristics of the faults and their tectonic evolutionary relationship with adjacent tectonic units,this study used ambient noise data recorded by a seismic array deployed in Hefei City and Chao Lake,constructing a 3-D velocity model at the depth of 1–8 km.Then a multi-scale high-resolution 3-D velocity model of this area was constructed by this new upper crustal velocity model with the previous middle and lower crustal model.The new model reveals that a high-velocity belt is highly consistent with the strike of the Tanlu Fault Zone,and a low-velocity sedimentary characteristic is consistent with the Hefei Basin and Chao Lake depression.The distribution morphology of high and low velocity bodies shows that the sedimentary pattern of Hefei-Chao Lake area is closely related to the tectonic evolution of the Tanlu Fault Zone since the Mesozoic.This study also identifies multiple low-velocity anomalies in the southeastern Hefei City.We speculate that strong ground motion during the 2009 Feidong earthquake(magnitude of 3.5)was related to amplification by the thick sediments in the Hefei Basin.We also discuss further applications of multi-scale high-resolution models of the shallow layer to strong ground motion simulations in cities and for earthquake disaster assessments.

Desertification evolution prediction for lake area of Minqin oasis based on integration of GIS and cellular automata

The Minqin oasis is surrounded on three sides by the Tengger Desert and the Badanjilin Desert, and it prevents these two deserts from converging. However, in recent years it has become the worst ecological environment in the Lake area due to deficient water resources, continual declines in the groundwater level and quality （increasing mineralization and salination）, which are causing in- creasing desertification. In this study, Landsat Thematic Mapper （TM） remote images from 1992, 1998, 2002, and 2006 of the Lake area of the Minqin oasis are interpreted to analyze the desertification evolution. A combination of an ArcObjects module and a cellular automata model is used to build a model simulating the desertification dynamics; the forecasting accuracy of this model is shown to reach up to 90%. The desertification situation in 2012 is forecasted by this model, and the results showed that, from 2006 to 2012, the green land area will be reduced by 999.92 hm2 （l.59 percent of the total oasis area）, the desertification land area will be reduced by 3,000.68 hrn2 （4.78 percent of the total oasis area）, and sand land area will increase by 4,000.6 hm2 （6.37 per- cent of the total oasis area）. The sand land is predicted to become more widespread, and more than 18% sand land will be distrib- uted in the center of green land in the Lake area. In other words, more and more abandoned green land （mined farm land） will be transformed into sand land, and this will intensify the desertification.

Climate Evolution Recorded by Organic Carbon Stable I sotope since 5 kaB.P.in Poyang Lake Area, China

Based on the data of organic carbon stable isotope ratios and magnet ic susceptibility, climate evolution in the past 5 kaB.P. in Poyang Lake plain (in Jiangxi Province) has been reconstructed. The results of the research indicate that the climate evolution can be divided into nine stages in the past 5 kaB.P.. Comparisons of different regional environmental records suggest that the intens ity and the temporal spatial changes of monsoon in China mainly controlled the climate evolution.

Emergy Analysis of the Agricultural Eco-economic System in Dongting Lake Area of Hunan Province

[ Objective] The reseamh aimed to discuss eco-efficiency of the agro-ecosystem in Dongting Lake area of Hunan. [ Method] By referring to emergy reseamh method, emergy structure, function and efficiency of the system were analyzed according to emergy input -output data of the system in 2009. [ Result] The system had developed economy, and mechanization and modernization degrees were higher. Emergy output of the system was unbalanced, and market pricing of the agricultural product was significantly lower, especially farming product. Seen from sustainable development index and environmental loading ratio of the system, the system was full of vitality and development potential. The pressure of natural resources and environment was not very great, but the system accommodated too many populations. [ Conclusion] Basic direction of the agricultur- al policy in the zone was further shortening industrial and agricultural price scissors, continuing to implement price protection of the farming product, adjusting agricultural and product structures and transferring surplus labor.

Analysis on Change of the Vegetation Cover in Poyang Lake Area from 1991 to 2005

[Objective] The reseamh aimed to analyze variation of the vegetation cover in Poyang Lake area from 1991 to 2005. [Method] Based on Landsat TM remote sensing images of 1991 and 2005 in Poyang Lake area, NDVI dimidiate pixel model was used to calculate vegetation cover- age. By transfer matrix, temporal-spatial change of the vegetation cover grade in the area was analyzed. [ Result] Vegetation cover in this region overall presented increase trend from 1991 to 2005, and forestry area increased somewhat. But at the same time, farmland area decreased to some extent. Sandlot and bare land also increased slightly. [ Conclusion] Governments and relevant departments should reasonably allocate land re- sources and protect natural ecology environment.

Study on regulation of potassium loss and its balance characteristics from typical paddy soils in Dongting Lake area

Potassium loss due to runoff and leaching, crop uptake, and K-fertilizer input, irrigation and wet deposition was studied, subsequently potassium balance characteristics was analyzed using lysimeter modeled two typical paddy soils from double rice field in Dongting Lake area. K losses due to runoff and leaching in Alluvial Sandy Loamy Paddy Soil （ASL） with lower cation exchange content （CEC） and clayey granule content were increased significantly compared with those in Reddish Yellow Loamy Paddy Soil （RYL） with higher CEC and clayey granule content. Compared with RYL, lower economic and biological yield due to lower capacity of nutrient and water keeping in ASL resulted in lower K uptake. So potassium deficit in double rice field of RYL was more serious than that of ASL because main K proportion was accounted by crop uptake. Available K in soil of surface layer （0-15 cm） was decreased significantly due to long term nutrient management of K deficit in double rice field. The straw return paddy field was suggested as an effective way to increase soil K and balance K deficit in double rice field because large amount of potassium was enriched in rice straw at harvest.

SWOT Analysis of the Tourism Development in Dongping Lake Area of Shandong Province

Dongping Lake,Which has abundant tourism resources and advantages in geography,is one of the important Water Control Projects of South-to-North Water Diversion Project in Northern China.Though it has a wide prospect,the Dongping Lake area is lack of unified plan and management.The result of this study will provide effective solutions to the further development in Dongping Lake based on SWOT method.

Lake Area Changes and the main causes in the hinterland of Badain Jaran Desert during 1973–2010,China

Lake area information in the Badain Jaran Desert in 1973, 1990, 2000, and 2010 was obtained by visual interpretation and water index analysis of remote sensing images, based on the spatial and temporal characteristics of lake area changes during 37 years. Results indicated that the nttmber of lakes declined from 94 to 82 and the total surface area was reduced by 3.69 km2 during 1973-2010. The desert lake area reduced by different degrees in different periods, but this occurred most rapidly during 1973-1990. According to the statistics of lake area changes, lake area decreases mainly occurred in the lakes with areas less than 0.2 km2, while the areas of lakes greater than 0.9 km2 only fluctuated. The changes of lake areas were probably due to changes in the quantity of underground water supplies rather than the effects of local climate change or human factors.

Emergy Analysis of Agro-ecosystem in Poyang Lake Area

By using emergy analysis theory and methods, we conduct quantitative analysis on the input and output of emergy, and sustainable development of agro-ecological system in Poyang Lake Area. The results show that compared with the national average, the environmental loading ratio is relatively low in this area; the net emergy yield rate is high; the sustainable development ability is strong. Finally according to the results of emergy analysis, corresponding countermeasures are put forward as follows: develop agriculture based on the existing rich natural resources; increase technological inputs; develop circular agriculture; promote sustainable agricultural development.

Dynamic Analysis of Land Cover in Four-Lake Area of Jianghan Plain Based on MODIS-EVI Time Series Data

According to the time series data of Enhanced Vegetation Index (EVI) in Four-Lake Area of Jianghan Plain during the period 2001-2007, we use Harmonic Analysis of Time Series (HANTS) to conduct cloud removing processing, and calculate the sum of square N of time series value of each pixel. The pixels with N>0.25 are classified as vegetation coverage area; the pixels with N<0.25 are classified as non-vegetation coverage area. As to vegetation coverage area, we use the second-order difference method to judge the frequency of peak value of EVI time series data. Within one year, the vegetation coverage area with peak value happening 1 time is woodland and grassland; the vegetation coverage area with peak value happening 2 times is arable land; the vegetation coverage area with peak value happening 3 times or more is vegetable land. Supervised classification method is used to identify cities, towns, water area in non-vegetation coverage area and woodland, grassland in vegetation coverage area. We draw the land cover classification diagram of Four-Lake Area in the period 2001-2007. In comparison with the land cover classification based on multitemporal ETM data in 2001, the difference of area of arable land is within 10%. Using MODIS-EVI data, we can rapidly and efficiently conduct land cover classification with low cost. The dynamic analysis results indicate that the area of arable land is in the process of declining, while the area of other cover types shows an increasing trend.

Climate-Driven Changes in Lake Areas for the Last Half Century in the Valley of Lakes, Govi Region, Southern Mongolia

This study presents the changes in lake areas in the Valley of Lakes, the Govi region, southern Mongolia. The recent changes in lake areas show decreases depending on vulnerability of lake basins and response of Govi landscape to the present climatic warming. During the recent 44 - 45 years (from 1970 to 2014 or 2015), modern lakes have encountered the present rapid increase in temperature, water evaporation and drying up that induced the reduction in lake areas in the Valley of Lakes. The finding of the reduction in lake areas is consistent with the trends on increasing in temperature since 1995 and fluctuating precipitation since 1975. Investigations with detailed chronology of lake sediment are needed from the lakes to review a more complete evolution of lake basins during the Late Quaternary paleoclimatic history in Mongolia and Central Asia.