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China introduced sponge city development (SCD) as a policy initiative to address the complex, interlinked water challenges, such as urban pluvial flooding and water pollution, faced by urban development under climatic change and rapid urbanization. The initiative relies on low‐impact development (LID) techniques to integrate ecosystem conservation and urban development, with the aim to maintain or restore natural landscapes and their water regulating capacity as a way to mitigate urban flooding and associated pollution while augmenting water supply. While the country prepares for SCD demonstration and upscaling after pilot implementation since 2014, the initiative is subject to a design deficit in policy implementation that has received little consideration in both the literature and the policy arena but that negatively affects the effectiveness of SCD and its long run impact as intended by the policy. In this paper, we examine the design deficit by mapping and analyzing the policy implementation for SCD in the framework of theory of change (TOC). We present key conditions for individual components in SCD implementation to deliver causal pathways from program inputs to long‐term impacts, with identified issues characterizing the design deficit. We provide an overview of the literature on SCD to shed some light on current research while identifying knowledge gaps. The paper proposes and justifies the framework of ecosystem services as an innovative design tool to deliver a systematic approach needed to address the design deficit, paving the pathways for SCD from inputs to impacts fully developing the policy potential for green urban transition with resilience and sustainability. [ABSTRACT FROM AUTHOR]

Rapid urbanization and climate change are two grand challenges faced by many cities in pursuing sustainable urban development. While ecosystem-based adaptation practices are increasingly recognized and adopted across the world as an important urban development strategy, their effective implementation in diverse biophysical conditions and development contexts is of interest, requiring scientific research and learning. This paper presents the case of China in implementing an ecosystem-based approach – sponge city development – to address the water-related challenges of urbanization and climate change. It draws on the literature to synthesize understanding of the interaction between the urban landscape, urban development, and ecosystem services, and proposes mainstreaming an ecosystem service framework in spatial planning and performance evaluation to guide ecosystem-based adaption practices. Focusing on China's practice, the paper develops a five-step procedure for operationalizing and mainstreaming ecosystem services so as to improve policy implementation for sponge city development. This paper aims to provide a practical perspective to help enhance ecosystem-based adaptation in urban development to better address the challenges of urbanization and climate change. Cities are increasingly looking into ecosystem-based adaptation, as an integrated part of urban development, to increase resilience to climate change and to promote urban sustainability. China's experience with implementing a national initiative called sponge city development contributes to learning and an understanding of ecosystem-based adaptation practices to address urbanization and climate change challenges. Existing literature shows the need and potential for an ecosystem service framework to guide spatial planning and performance evaluation for ecosystem-based adaptation. China is in a unique position to mainstream an ecosystem service framework in sponge city development to improve current practice and to promote climate-resilient and ecosystem-integrated urban development. A five-step empirical procedure outlines a systematic approach for mainstreaming ecosystem services, contributing to the literature and policy practice to build urban resilience and sustainability in the face of urbanization and climate change. [ABSTRACT FROM AUTHOR]

Snail intermediate host monitoring and control are essential for interrupting the parasitic disease schistosomiasis. Identifying large-scale high-risk areas of snail spread after floods has been greatly facilitated by remote sensing imagery. However, previous studies have usually assumed that all inundation areas carry snails and may have overestimated snail spread areas. Furthermore, these studies only used a single environmental factor to estimate the snail survival risk probability, failing to analyze multiple variables, to accurately distinguish the snail survival risk in the snail spread areas. This paper proposes a systematic framework for early monitoring of snail diffusion to accurately map snail spread areas from remote sensing imagery and enhance snail survival risk probability estimation based on the snail spread map. In particular, the flooded areas are extracted using the Sentinel-1 Dual-Polarized Water Index based on synthetic aperture radar images to map all-weather flooding areas. These flood maps are used to extract snail spread areas, based on the assumption that only inundation areas that spatially interacted with (i.e., are close to) the previous snail distribution regions before flooding are identified as snail spread areas, in order to reduce the misclassification in snail spread area identification. A multiple logistic regression model is built to analyze how various types of snail-related environmental factors, including the normalized difference vegetation index (NDVI), wetness, river and channel density, and landscape fractal dimension impact snail survival, and estimate its risk probabilities in snail spread area. An experiment was conducted in Jianghan Plain, China, where snails are predominantly linearly distributed along the tributaries and water channels of the middle and lower reaches of the Yangtze River. The proposed method could accurately map floods under clouds, and a total area of 231.5 km2 was identified as the snail spread area. The snail survival risk probabilities were thus estimated. The proposed method showed a more refined snail spread area and a more reliable degree of snail survival risk compared with those of previous studies. Thus, it is an efficient way to accurately map all-weather snail spread and survival risk probabilities, which is helpful for schistosomiasis interruption. [ABSTRACT FROM AUTHOR]

Quantitative analysis of the contribution rate of China’s hydraulic science and technology and analysis of the underlying reasons behind changes provide an important foundation upon which the government can formulate water policies. This paper abandons the assumption of a scale economy and separates the changes of benefits brought about by the scale from scientific and technological progress, thus changing the C-D production function from linear to nonlinear. Based on a feedforward neural network, it calculates the coefficient of the output elasticity, the economic contribution rate of China’s hydraulic science and technology and the scale economies for each year using relevant data from 1981 to 2016. The results show that (1) the average contribution rate of capital investment from 1981 to 2016 was 47.3%, and the average contribution rate of labor from 1981 to 2016 was 9.1%. It is not obvious that the significant increase in the labor force has contributed to the growth of China’s water conservancy industry. (2) The average contribution rate of scale economies in 1981–2016 was 26.7%, and the contribution rate of scale economies is negatively correlated with the capital contribution rate. (3) The average contribution rate of China’s hydraulic science and technology was 43.6% from 1981 to 2016, and the average contribution rate of the total factor productivity after removing scale economies from 1981 to 2016 was 16.9%. During the period of the 6th Five-Year Plan(1981~1985), the contribution rate of water conservancy science and technology was relatively high. Since that time, it has remained at 40%. In recent years, as water conservancy reforms in key areas have made positive progress, scientific and technological progress has increased the growth of water conservancy benefits annually. [ABSTRACT FROM AUTHOR]

Recent rapid urbanisation means that China has invested in an enormous amount of infrastructure, much of which is vulnerable to natural hazards. This paper investigates from a spatial perspective how the Chinese infrastructure system is exposed to flooding and drought hazards. Infrastructure exposure across three different sectors-energy, transport, and waste-is considered. With a database of 10,561 nodes and 2863 edges that make up the three infrastructure networks, we develop a methodology assigning the number of users to individual infrastructure assets and conduct hotspot analysis by applying the Kernel density estimator. We find that infrastructure assets in Anhui, Beijing, Guangdong, Hebei, Henan, Jiangsu, Liaoning, Shandong, Shanghai, Tianjin, Zhejiang-and their 66 cities-are exceptionally exposed to flooding, which affects sub-sectors including rail, aviation, shipping, electricity, and wastewater. The average number of infrastructure users who could be disrupted by the impacts of flooding on these sectors stands at 103 million. The most exposed sub-sectors are electricity and wastewater (20 and 14 % of the total, respectively). For drought hazard, we restrict our work to the electricity sub-sector, which is potentially exposed to water shortages at hydroelectric power plants and cooling water shortage at thermoelectric power plants, where the number of highly exposed users is 6 million. Spatially, we demonstrate that the southern border of Inner Mongolia, Shandong, Shanxi, Hebei, north Henan, Beijing, Tianjin, south-west of Jiangsu-and their 99 cities-are especially exposed. While further work is required to understand infrastructure's sensitivity to hazard loading, the results already provide evidence to inform strategic infrastructure planning decisions. [ABSTRACT FROM AUTHOR]

Background: Oncomelania hupensis is the exclusive intermediate host of Schistosoma japonicum in China. Snail control is an essential component of schistosomiasis elimination programme. With 70 years of continuous efforts, the range of O. hupensis had reduced significantly, but slowed down in last decades. A large number of levees against flooding were constructed along Yangtze River and its affiliated lakes in the middle and lower reaches, which influenced the hydrology and ecology in the alluvial plains. The purpose of this study was to assess the impact of levees on the distribution of O. hupensis in the middle and lower reaches of the Yangtze River. Methods: The snail habitats were digitalised by hand-held GPS system. The years for discovery and elimination of snail habitats were extracted from historical records. The accumulated snail-infested range for each habitat was calculated on the basis of annual reports. The current distribution of O. hupensis was determined by systematic and environmental sampling. The geographical distribution of levees was obtained from satellite imagery. To assess the impact of levees, the data pertaining to O. hupensis were divided into two parts: inside and outside the Yangtze River. Joinpoint regression was utilised to divide the study time span and further characterise the regression in each period. The 5-year-period moving averages of eliminated area infested by snails were calculated for the habitats inside and outside Yangtze River. The moving routes of corresponding geographical median centres were simulated in ArcGIS. Hotspot analysis was used to determine the areas with statistical significance clustering of O. hupensis density. Results: Three periods were identified according to Joinpoint regression both inside and outside Yangtze River. The area infested by O. hupensis increased in the first two periods. It decreased rapidly outside Yangtze River year over year after 1970, while that inside the Yangtze River did not change significantly. Furthermore, the latter was significantly higher than the former. It was observed that the present density of O. hupensis inside Yangtze River was lower than outside the Yangtze River. The median centre for eliminated ranges inside Yangtze River wavered between the east (lower reach) and the west (middle reach). In contrast, the median centre for eliminated ranges continuously moved from the east to the west. Conclusions: Our findings indicated that the levees had a considerable negative impact on the distribution of O. hupensis outside Yangtze River. Some hotspots observed in the irrigation areas need a sluice system at the inlet of branch for snail control. The major distribution of O. hupensis located in Hubei might be caused by severe waterlogging. The intensive surveillance should be implemented there. The biggest two freshwater lakes, the major endemic regions historically, were identified as cold spots. The long-term impact of Three Gorges Dam on the distribution of O. hupensis in the lakes should be monitored and evaluated. [ABSTRACT FROM AUTHOR]

Catastrophic flooding resulting from extreme meteorological events has occurred more frequently and drawn great attention in recent years in China. In coastal areas, extreme precipitation and storm tide are both inducing factors of flooding and therefore their joint probability would be critical to determine the flooding risk. The impact of storm tide or changing environment on flooding is ignored or underestimated in the design of drainage systems of today in coastal areas in China. This paper investigates the joint probability of extreme precipitation and storm tide and its change using copula-based models in Fuzhou City. The change point at the year of 1984 detected by Mann-Kendall and Pettitt’s tests divides the extreme precipitation series into two subsequences. For each subsequence the probability of the joint behavior of extreme precipitation and storm tide is estimated by the optimal copula. Results show that the joint probability has increased by more than 300% on average after 1984 (α = 0.05). The design joint return period (RP) of extreme precipitation and storm tide is estimated to propose a design standard for future flooding preparedness. For a combination of extreme precipitation and storm tide, the design joint RP has become smaller than before. It implies that flooding would happen more often after 1984, which corresponds with the observation. The study would facilitate understanding the change of flood risk and proposing the adaption measures for coastal areas under a changing environment. [ABSTRACT FROM AUTHOR]

Background: Farming on sloping lands has historically led to forest loss and degradation in China, which coupled with unsustainable timber extraction activities, was deemed responsible for catastrophic flooding events in the late 1990s. These events led to the introduction of forest policies targeting ecological conservation and rural development in China, a process epitomized by the launch of the conversion of cropland to forest program (CCFP) in 1999. This systematic review responds to the question: What are the environmental and socioeconomic effects of China’s Conversion of Cropland to Forest Program after the first 15 years of implementation? Methods: Based on the published protocol, we searched for English language studies published between 1999 and 2014, and screened them for relevance and eligibility in two stages (titles and abstracts followed by full texts), after which they were further assessed for potential sources of bias before data extraction and analyses. Following initial screening of 879 titles and abstracts, 169 studies underwent full text screening, followed by 61 studies being subjected to quality assessment. Eighteen papers did not meet minimum quality criteria, while the remaining 43 papers were eligible and underwent data extraction and subsequent analyses. Among the final set of 43 studies were four national-level studies, seven regional-level studies, and 32 county-level (or below) studies. The majority of studies were published after 2009 and evaluated impacts within the first 5 years of CCFP implementation, such that the long-term impacts of the program remain open for further investigation. Results: A skewed temporal and geographic distribution of the examined studies limits the generalizability of the results, though the evidence base confirms a substantial increase in forest cover and associated carbon stocks linked to reallocation of sloping agricultural land to forest. To some degree, soil erosion has been controlled and flood risk reduced at local scales. Meanwhile household incomes have increased and rural employment has readjusted towards off-farm sectors. However, some studies also indicate instances of diminished food security and increasing social inequality. Finally, several studies indicate suboptimal regional or localized trade-offs among specific ecosystem services, including carbon sequestration vs. water discharge rates, flood control vs. riparian soil replacement, and forest productivity vs. biodiversity. Conclusions: Additional research on long-term environmental impacts and program effects in under-studied regions, particularly southern and western provinces, is necessary. In terms of recommendations for future research on the CCFP, there is a significant need to examine confounding factors, ideally through the selection of matching control groups to CCFP participants, and to ensure that sampling methodologies are more representative of selected study sites and the overall targeted area. There remain many opportunities to assess specific socioecological effects, upon which to base future policy decisions and more broadly inform ecological restoration and eco-compensation in both theory and practice. [ABSTRACT FROM AUTHOR]

Global management of wetlands to suppress greenhouse gas (GHG) emissions, facilitate carbon (C) sequestration, and reduce atmospheric CO2 concentrations while simultaneously promoting agricultural gains is paramount. However, studies that relate variability in CO2 and CH4 emissions at large spatial scales are limited. We investigated three-year emissions of soil CO2 and CH4 from the primary wetland types of the Liaohe Delta, China, by focusing on a total wetland area of 3287 km2. One percent is Suaeda salsa, 24% is Phragmites australis, and 75% is rice. While S. salsa wetlands are under somewhat natural tidal influence, P. australis and rice are managed hydrologically for paper and food, respectively. Total C emissions from CO2 and CH4 from these wetland soils were 2.9 Tg C/year, ranging from 2.5 to 3.3 Tg C/year depending on the year assessed. Primary emissions were from CO2 (~98%). Photosynthetic uptake of CO2 would mitigate most of the soil CO2 emissions, but CH4 emissions would persist. Overall, CH4 fluxes were high when soil temperatures were >18°C and pore water salinity <18 PSU. CH4 emissions from rice habitat alone in the Liaohe Delta represent 0.2% of CH4 carbon emissions globally from rice. With such a large area and interannual sensitivity in soil GHG fluxes, management practices in the Delta and similar wetlands around the world have the potential not only to influence local C budgeting, but also to influence global biogeochemical cycling. [ABSTRACT FROM AUTHOR]

This paper presents a modeling application of surface runoff using the Hydrologic Modelling System (HEC-HMS). A case study was carried out for the Jianghe watershed, a typical semi-arid and sub-humid geo-climatic region in northern China. Two modeling schemes using different descriptive sub-mechanism models provided by HEC-HMS for runoff volume, direct runoff and routing (channel flow) were investigated. The modeling results were compared with historical observation data. This work shows that HEC-HMS can be a suitable modeling tool for specific situations in China. With the appropriate selection of the sub-mechanism models, HEC-HMS can be applied to various situations, including the typical semi-arid and sub-humid conditions in northern China. [ABSTRACT FROM AUTHOR]

Small and micro businesses bear the brunt of climate change impacts in the climate-challenged economy. Vulnerability is embedded into the socio-economic trajectories of their primary decision-makers. Multiple vulnerabilities may arise if the decision-makers' socio-economic conditions are associated with climate-sensitive business characteristics. Previous research has provided little evidence on such linkages, thus losing insights into how different facets of vulnerability interact and evolve over time. This paper explores the interactions between elements of small business vulnerability and the socio-economic characteristics of their primary decision-makers. It draws on the results of a survey involving 116 owner-managers of small and micro businesses and in-depth interviews with a sub-sample. Study areas are three remote coastal communities in Hong Kong exposed to high floods. Results show that such interactions exist in multiple, non-linear ways. Socio-economic disadvantages (i.e. low education attainment, old age, low income, and female) are related to some aspects of small business vulnerability, while playing a role in mitigating or avoiding other aspects of it. The findings call for building frameworks that account for the multiple spheres in which vulnerabilities are engendered and their interactions, while allowing for complexities and feedback mechanisms. [ABSTRACT FROM AUTHOR]

Cucumber production in China is declining due to various pathologic diseases, but the technology for plant disease detection is not mature and requires high labor costs. Moreover, since planting sites are typically high-density scenes, most photos are shot from various angles with messy backgrounds, resulting in poor classification reliability. In this paper, batches of cucumber leaf image data are collected from agricultural websites and then preprocessed through the image size normalization. A mobile-based recognition algorithm is proposed to identify cucumber diseases from leaf images in natural scenes, enabling farmers to detect diseases more quickly. The proposed algorithm allows farmers to upload cucumber pictures, and rapidly and accurately classify them with high accuracy. With a improved network based on MobileNet V3, the classification of seven kinds of cucumber leaf diseases can be quickly and accurately completed. The network model is achieved by selecting appropriate parameters, optimizers, and batch capacity using the single-variable method. Additionally, a new training strategy called the flooding method is applied in the model, replacing the traditional strategy that relies solely on loss decline. An accuracy of 83.3% is achieved on our custom dataset. Finally, two public datasets, namely PlantVillage and Apple Disease, are selected for migration experiments. The achieved accuracy rates for these datasets are 99% and 98.1% respectively, demonstrating the universality of the proposed strategy. The code for all the experiments will be made available for reference on the GitHub repository at https://github.com/YiQuanMarx/Agricultural_Diseases_Dentification. • An algorithm to identify seven cucumber diseases in natural scenes is proposed. • Lightweight and fast MobileNetv3 network is achieved by various optimizations. • Replacing the strategy of loss decline, flooding method is applied for high accuracy. • Eight state-of-the-art algorithms are selected for performance comparison. • Performance criteria cover accuracy, loss, parameters, computation time, storage etc. [ABSTRACT FROM AUTHOR]

Hopea chinensis (Merr.) Hand.-Mazz. is a Class II national key protected plant and Plant Species with Extremely Small Populations in China. In order to further analyze why H. chinensis is endangered and optimize conservation techniques, we carried out a study on the effects of seed biological characteristics and environmental factors on the seed germination and seedling growth of H. chinensis. The results show that there were no significant differences in seed morphology between four populations in southern China, but there were significant differences in calyx lobe morphology and seed germination. The removal or retention of the calyx lobes or the seed coat had no significant effect on seed germination. The weight of individual H. chinensis seeds was mainly >1.0 g, with small seeds (<0.5 g) not germinating, whereas seeds >2.0 g had the highest germination rate and fastest seedling growth. H. chinensis produces typical recalcitrant seeds, being sensitive to natural dehydration, with dehydration for 8 d reducing seed viability by 50%, whereas dehydration for 16 d resulted in seeds with zero viability. H. chinensis seeds are light-neutral and capable of germination at a temperature of 30 °C and on a substrate with good water retention and aeration. The seeds are not tolerant of drought, salinity, or flooding. In conclusion, the unique biological characteristics of H. chinensis seeds and the specific habitat which they inhabit contribute to a significant loss of viable seeds, which negatively affects the population's ability to regenerate and achieve maintenance. [ABSTRACT FROM AUTHOR]

This paper is to present an efficient approach to enriching the quantification model of human-riverine interactions and its anthropogenic impact by a retrospective study on one of the four most famous historical hydraulic projects in China, the Tuoshan Weir. It was constructed in 833 AD and had trajectories of natural resilience and hydraulic engineering maturity more than thousand years. Extensive historical data and maturation procedure of the hydraulic system were used judiciously to examine the spatial patterns of the long-term water conservancy system with agriculture, urbanization and civilization of Ningbo City in Zhejiang Province, Southeast China. Interaction framework is assessed from historical perspective and the deposition rate ( DR) is calculated by analyzing the continuous increase of the Tuoshan Weir height. The results show that the declining DR during the 1180 years guaranteed the beneficial role the Tuoshan Weir played in spite of some negative river responses caused by the increase of sediment deposition and decrease of fresh water-retention capacity. The following up revamped workings and well matured hydraulic system around the Tuoshan Weir also contribute a lot to the designed mission of the weir. We conclude that hydraulic system maturation is very important for the proper function and life span of huge hydraulic projects. [ABSTRACT FROM AUTHOR]

Karst terrains are generally regarded as a fragile and vulnerable environment. China's karst is mainly developed in pre-Triassic, old-phase, hard, compact carbonate rock. The lack of soil cover in bare karst land can enhance desertification. Its underground drainage system can aggravate both drought and flooding problems; the interconnected surface and subsurface conditions allow for easy contamination by pollutants. Moreover, karst terrains quite often suffer from a series of engineering problems, such as water infiltrating into mines or transportation tunnels, leakage from reservoirs, and failure of building foundations. As resources and energy exploitation intensified in recent years, karst areas in Southwest China faced some severe geo environmental problems. In order to find out how the problems action and evolution in recent years, field and laboratory investigations were conducted in Guangxi autonomous region, Guizhou, Yunnan, Guangdong, Hunan, Hubei provinces, and Chongqing municipality. About 100 experts from the Provincial Geological Survey and graduate students took part in this project. Several symposiums were held during those 3 years. Besides the in situ survey, data were collected from hydrogeological survey results since 2000 when the new round of land resources investigation began. After analyzing these data, rock desertification, drought and flooding, and contamination and engineering geological environmental problems were considered the most prevalent problems in karst areas in Southwestern China. The status of each problem is elaborated upon in this paper and should be considered for future sustainable development. [ABSTRACT FROM AUTHOR]

The paper explores the use of Resilience Theory to provide an improved theoretical framework for the analysis of socio-ecological interactions over decadal—millennial timescales. It identifies landscape system behaviour through analysis of proxy records for land use, erosion and monsoon intensity over the past 3000 years in the Erhai lake-catchment system, Yunnan, SW China. Analysis of the records shows the possibility of alternative steady states in the landscape, as expressed by the relationship between land use and erosion. In particular, a period of agricultural expansion ~1400 cal. yr BP triggered rapid gully erosion that led to the formation of an eroded landscape state that has existed since ~800 cal. yr BP to the present day. Comparison of detrended time-series data suggests that over 3000 years erosion and land use should be considered 'slow' processes relative to the 'faster' monsoon intensity and flooding. In the past, the effects of high monsoon variance on flooding have been suppressed by paddy farming and the maintenance of terraced field systems. Mapping the Adaptive Cycle on to the millennial record of land use and erosion suggests that the modern landscape may be approaching a 'conservation' phase characterized by minimum resilience. Such 'historical profiling' of modern landscapes offers a new dimension for hypothesis testing, for the development and testing of simulation models and for the creation of appropriate management strategies. [ABSTRACT FROM AUTHOR]

Artificially contaminated soils (A, B) and naturally contaminated soil (S2) in China were used as the tested soils, and the effect of continuous flooding on the changes of Eh, pH and the speciation of cadmium, lead in contaminated soils was studied in the paper. The results indicated that soil Eh decreased with flooding time, and that soil pH increased with flooding time. The changes of soil pH ceased after 60 days of submergence. The exchangeable Cd and Pb decreased obviously during the flooding process from the results of five-step sequential extraction. The calculations of mobility factor (MF) showed that Cd mobility significantly decreased in artificially contaminated soils (A, B) after the flood. But the change of Pb mobility was not significant after the flood, although a decrease of Pb concentration in the exchangeable fraction (SE) was observed. [ABSTRACT FROM AUTHOR]

Flooding is often affected by multiple factors such as climate, hydrology, infrastructures, etc. This paper attempted to examine multifractal methodology as a tool to characterize the indicators for flood magnitude. Results from this study have shown that the multifractal analysis can be an encouraging method to identify the dynamic features of flood process, particularly for rivers in the mountainous region such as the Wujiang River in this study. The flood peak, total flood volume, the 24-, 48-, and 72-h flood volumes were selected as flood magnitude indicators in this study. It was found that the five indicators showed strong multifractal feature. The singularity spectrum showed the flood volume had the highest fluctuation among all five indicators. The span of the multifractal singularity showed the flood volume had stronger multifractal characteristic. The flood volume was sensitive to local fluctuations, but other four indicators were not sensitive to fluctuations. This study also showed, for the Wujiang River, multifractality were in the order from greatest multifractal strength to the smallest were the flood volume, the maximum 24-h flood volume, the peak flood, the maximum 48-h flood volume and the maximum 72-h flood volume, which was due to the terrain features in Wujiang River and its drainage area. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes 20th century climate and human impacts on terrestrial and fluvial systems in the Dabie Mountains, Anhui Province, China, based on analyses of four types of information. Analyses of particle size, mineral magnetism, organic carbon, nitrogen and phosphorus in a sediment core taken from the Longhekou reservoir, built in 1958 AD in the upper reaches of Hangbu River, provide an ∼45 year record of fluvial responses, while monitored meteorological and hydrological data provide records of climate and river discharge. Census data compiled for the local Shucheng County provide records of population and land use, complemented with analyses of satellite images. The Xiaotian river delivers over 65% of the total water and silt to the reservoir. Analyses indicate that the fluvial regime tracks the monsoon climate over seasonal timescales, but human activities have a strongly mediating effect on sediment supply, sediment delivery and, to a lesser extent, runoff over longer timescales. Notable periods of human impact on erosion include the Great Leap Forward (1958–1960) and Great Cultural Revolution (1966–1976). A rising trend in precipitation and new land use changes at the present time may be leading to an enhanced flood risk. [Copyright &y& Elsevier]

Concerns regarding climate change have recently spotlighted the devastating impacts of flooding. In this regard, disaster preparedness is known to mitigate against potential loss suffered as a consequence of flood disasters. Extant research has explored the influence of residents' experience and attitude on disaster preparedness behavior as separate factors; however, research to date has yet to consider these inter-related factors simultaneously. Accordingly, this study explores this relationship, taking rural residents of the flood-prone regions of Sichuan Province, China, as the research subject. Exploratory factor analysis and ordered logistic regression are used to ascertain the effects of flood experience and attitude on residents' disaster preparedness behavior. Results show the following. (1) The level of disaster preparedness behavior of rural residents is relatively low. (2) Respondents who are older, more educated, or who have lived locally for longer are more likely to be better prepared for flood disasters. (3) On the other hand, respondents with higher income, either as individuals or households, are less prepared. (4) Previous flood experience and disposition toward disaster also impacts preparedness behavior. On the basis of these findings, the following suggestions are proposed as mitigation policies for flood-prone areas. (1) Structural flood control measures should be organically combined with daily disaster preparedness. (2) Rural areas affected by devastating floods should offer psychological counseling to residents in order to reduce states of fear and helplessness. (3) Government departments should inform residents in real time of flood warnings and of flood control measures. (4) Lastly, relevant local departments should educate local residents in flood preparedness. Taken together, these measures can be expected to improve living conditions, people's trust in the media, and in the government's flood control capacity. [ABSTRACT FROM AUTHOR]

Floods out of all other water problems cause very large damages in China. Previous flood management plans mainly focused on a single river by controlling its water level and conveyance capacity, while research on mitigation solutions to flooding issues in river-lake systems is scarce. This study considers the Huai River - Lake Hongze system, which is one of the largest river-lake systems in China. Very large damages associated with small floods are frequently observed in this river-lake system, although a series of flood management measures have been implemented in the Huai River Basin since the middle of the last century. An unstructured-grid finite-volume numerical model was applied to simulate hydrodynamic processes in this system, which is characterized by discrepant spatial scales between these two types of water bodies. It is found that the lake affects the upstream river flooding, but lowering the lake level would have limited effects that would be rapidly impaired by the sharp meander bend connecting the river and the lake. The artificial cutoff of this intensively-embanked bend has great potential in reducing the river stage and flood damages, as the construction of a diversion channel would shorten the flow path and increase the hydraulic gradient. This study extends the current knowledge about the hydrodynamics of river-lake systems and is beneficial to flood mitigation strategies for similar systems. [ABSTRACT FROM AUTHOR]

Background: Operation of the Three Gorges Reservoir (TGR, China) imposes a new water fluctuation regime, including a prolonged winter submergence in contrast to the natural short summer flooding of the rivers. The contrasting water temperature regimes may remarkably affect the survival of submerged plants in the TGR. Plant survival in such prolonged flooding might depend on the carbohydrate status of the plants. Therefore, we investigated the effects of water temperature on survival and carbohydrate status in a flood-tolerant plant species and predicted that both survival and carbohydrate status would be improved by lower water temperatures. Methodology: A growth chamber experiment with controlled water temperature were performed with the flood-tolerant species Arundinella anomala from the TGR region. The plants were submerged (80 cm deep water above soil surface) with a constant water temperature at 30°C, 20°C or 10°C. The water temperature effects on survival, plant biomass and carbohydrate content (glucose, fructose and sucrose and starch) in the viable and dead tissues were investigated. Principal findings: The results showed that the survival percentage of A.anomala plants was greatly dependent on water temperature. The two-month submergence survival percentage was 100% at 10°C, 40% at 20°C and 0% at 30°C. Decreasing the water temperature led to both later leaf death and slower biomass loss. Temperature decrease also induced less reduction in glucose, fructose and sucrose in the roots and leaves (before decay, p < 0.05), but only marginally significant in the stems (p < 0.05). However, the starch content level did not differ significantly between the water temperature treatments (p > 0.05). Different water temperatures did not alter the carbon pool size in the stems, leaves and whole plants (p > 0.05), but a clear difference was found in the roots (p < 0.05), with a larger pool size at a lower temperature. Conclusions/Significance: We concluded that (1) A. anomala is characterized by high flooding tolerance and sustained capability to mobilize carbohydrate pool. (2) The survival percentage and carbohydrate status of submerged A. anomala plants were remarkably improved by lower water temperatures. The survival of submergence seemed to be closely associated with the sugar content and carbohydrate pool size of the roots, which contained the lowest amount of carbohydrates. Three Gorges reservoir impoundment in winter is beneficial to the survival of submerged A. anomala in riparian area of the reservoir due to the low water temperature. [ABSTRACT FROM AUTHOR]

Building communities’ resilience to natural weather hazards requires the appropriate assessment of such capabilities. The resilience of a community is affected not only by social, economic, and infrastructural factors but also by natural factors (including both site characteristics and the intensity and frequency of events). To date, studies of natural factors have tended to draw on annual censuses and to use aggregated data, thus allowing only a limited understanding of site-specific hot or cold spots of resilience. To improve this situation, we carried out a comprehensive assessment of resilience to typhoon disasters in Nansha district, Guangzhou, China. We measured disaster resilience on 1×1-km grid units with respect to socioeconomic and infrastructural dimensions using a set of variables and also estimated natural factors in a detailed manner with a meteorological modeling tool, the Weather Research and Forecast model. We selected typhoon samples over the past 10 years, simulated the maximum typhoon-borne strong winds and precipitation of each sample, and predicted the wind speed and precipitation volume at the 100-year return-level on the basis of extreme value analysis. As a result, a composite resilience index was devised by combining factors in different domains using factor analysis coupled with the analytic hierarchy process. Resilience mapping using this composite resilience index allows local governments and planners to identify potential hot or cold spots of resilience and the dominant factors in particular locations, thereby assisting them in making more rational site-specific measures to improve local resilience to future typhoon disasters. [ABSTRACT FROM AUTHOR]

Rice cultivation has been challenged by increasing food demand and water scarcity. We examined the responses of water use, grain yield, and water productivity to various modes of field water managements in Chinese double rice systems. Four treatments were studied in a long-term field experiment (1998–2015): continuous flooding (CF), flooding—midseason drying—flooding (F-D-F), flooding—midseason drying—intermittent irrigation without obvious standing water (F-D-S), and flooding—rain-fed (F-RF). The average precipitation was 483 mm in early-rice season and 397 mm in late-rice season. The irrigated water for CF, F-D-F, F-D-S, and F-RF, respectively, was 263, 340, 279, and 170 mm in early-rice season, and 484, 528, 422, and 206 mm in late-rice season. Grain yield for CF, F-D-F, F-D-S, and F-RF, respectively, was 4,722, 4,597, 4,479, and 4,232 kgha-1 in early-rice season, and 5,420, 5,402, 5,366, and 4,498 kgha-1 in late-rice season. Compared with CF, F-D-F consumed more irrigated water, which still decreased grain yield, leading to a decrease in water productivity by 25% in early-rice season and by 8% in late-rice season. Compared with F-D-F, F-D-S saved much irrigated water with a small yield reduction, leading to an increase in water productivity by 22% in early-rice season and by 26% in late-rice season. The results indicate that CF is best for early-rice and FDS is best for late-rice in terms of grain yield and water productivity. [ABSTRACT FROM AUTHOR]

Responses of bald cypress (Taxodium distichum) and pond cypress (Taxodium ascendens) saplings in photosynthesis and growth to long-term periodic submergence in situ in the hydro-fluctuation zone of the Three Gorges Dam Reservoir (TGDR) were studied. Water treatments of periodic deep submergence (DS) and moderate submergence (MS) in situ were imposed on 2-year-old bald cypress and pond cypress saplings. The effects of periodic submergence on photosynthesis and growth were investigated after 3 years (i.e. 3 cycles) compared to a control (i.e. shallow submergence, abbreviated as SS). Results showed that pond cypress had no significant change in net photosynthetic rate (Pn) in response to periodic moderate and deep submergence in contrast to a significant decrease in Pn of bald cypress under both submergence treatments, when compared to that of SS. Ratios of Chlorophyll a/b and Chlorophylls/Carotenoid of pond cypress were significantly increased in periodic moderate submergence and deep submergence, while bald cypress showed no significant change. Diameter at breast height (DBH) and tree height of both species were significantly reduced along with submergence depth. Relative diameter and height growth rates of the two species were also reduced under deeper submergence. Moreover, bald cypress displayed higher relative diameter growth rate than pond cypress under deep submergence mainly attributed to higher productivity of the larger crown area of bald cypress. When subjected to deep subergence, both species showed significant reduction in primary branch number, while in moderate submergence, bald cypress but not pond cypress showed significant reduction in primary branch number. These results indicate that both bald cypress and pond cypress are suitbale candidates for reforestation in the TGDR region thanks to their submergence tolerance characteristics, but bald cypress can grow better than pond cypress under deep submergence overall. [ABSTRACT FROM AUTHOR]

Flooding regime changes resulting from natural and human activity have been projected to affect wetland plant community structures and functions. It is therefore important to conduct investigations across a range of flooding gradients to assess the impact of flooding depth on wetland vegetation. We conducted this study to identify the pattern of plant height, species richness and aboveground biomass variation along the flooding gradient in floodplain wetlands located in Northeast China. We found that the response of dominant species height to the flooding gradient depends on specific species, i.e., a quadratic response for Carex lasiocarpa, a negative correlation for Calamagrostis angustifolia, and no response for Carex appendiculata. Species richness showed an intermediate effect along the vegetation zone from marsh to wet meadow while aboveground biomass increased. When the communities were analysed separately, only the water table depth had significant impact on species richness for two Carex communities and no variable for C. angustifolia community, while height of dominant species influenced aboveground biomass. When the three above-mentioned communities were grouped together, variations in species richness were mainly determined by community type, water table depth and community mean height, while variations in aboveground biomass were driven by community type and the height of dominant species. These findings indicate that if habitat drying of these herbaceous wetlands in this region continues, then two Carex marshes would be replaced gradually by C. angustifolia wet meadow in the near future. This will lead to a reduction in biodiversity and an increase in productivity and carbon budget. Meanwhile, functional traits must be considered, and should be a focus of attention in future studies on the species diversity and ecosystem function in this region. [ABSTRACT FROM AUTHOR]

The article explores the paramount human rights and development crisis facing China and India—water scarcity. Both countries are facing alarming water shortages that are exacerbated by dangerous pollution levels, population growth, and climate change impacts such as drought, elevated water-borne disease episodes, flooding, and salt-water intrusion. Millions of citizens in China and India are deprived of safe, clean water in their environment, which threatens healthy socio-economic development. Through the perspective of the human security paradigm, the article analyzes the water security scenario in each country. [ABSTRACT FROM PUBLISHER]

In China, Zou Zhe (Memorials to the Throne, or Palace Memorials), an official communication to the emperors of China by local officials, offers an opportunity to reconstruct the spatial-temporal distributions of droughts at a high-resolution. A 223-year, 1689–1911, time series of drought events was reconstructed in this study based on 2494 pieces of Zou Zhe. The results show that: 1) on the temporal scale, the drought affected areas, i.e., number of affected counties, showed three peak periods during the last 223 years and nine extreme drought years with more than 300 counties affected have been identified; 2) on the spatial scale, there existed three drought-prone areas in China, i.e., Gansu province and Ningxia Hui Autonomous Region in Northwest China, Shandong, Hebei, and Henan provinces and Tianjin in the North China, and Anhui and Jiangsu provinces in Jianghuai area, respectively; 3) the drought-prone areas have been expanding from North China to South China since the second half of 19th century; 4) on the seasonal scale, summer witnessed the largest number of drought events. Meanwhile, the uncertainties of the results were also discussed, i.e. what caused the spatial-temporal distribution of drought. The results of this study can be used to mitigate the adverse effects of extreme weather events on food increasing and stable production. [ABSTRACT FROM AUTHOR]

Background: Agricultural activities on sloping lands have historically led to forest loss and degradation in China which, coupled with industrial pressures on the environment, were deemed responsible for catastrophic flooding events in the late 1990s. After these events, China's forest policy underwent a significant reorientation towards ecological conservation and rural development, a process epitomized by the Conversion of Cropland to Forest Program (CCFP). Launched in 1999, the CCFP integrates both socioeconomic and environmental objectives with the aim of reforesting smallholder cropland on sloping lands, while compensating farmers with payments for their lost income. Following 15 years of implementation, it is timely to conduct a comprehensive assessment of the state of knowledge about the CCFP's impacts on human populations and the environment. Methods/design: The primary research question asks "What socioeconomic and environmental effects has the Conversion of Cropland to Forest Program had on human populations and land resources during its first 15 years in China?" We use a theory of change and a Population-Intervention-Comparator-Outcome (PICO) framework to structure our systematic review, where populations of interest consist of both human populations and land resources targeted by the program, while the intervention of interest is the CCFP as defined by its component activities, including compensatory subsidies, skill-training, and enforcement with field checks. Outcomes are defined as both the socioeconomic and environmental impacts of the program. We will conduct a search for relevant English and Chinese language literature on Scopus, Web of Science, CAB Abstracts, AGRIS (FAO), and the China National Knowledge Infrastructure. Search results will be screened for relevance in a two stage process (titles and abstracts, followed by full texts) based on predefined eligibility criteria, and then further assessed for potential sources of bias. Extraction of data from those studies that have passed full-text screening will follow a coding protocol based on the PICO framework, and quantitative and qualitative analyses of the extracted data will be conducted and synthesized. Finally, a narrative report will present the findings of the review, alongside a geographic map illustrating the coverage of included studies compared with the actual implementation area of the CCFP. [ABSTRACT FROM AUTHOR]

Background: Agricultural activities on sloping lands have historically led to forest loss and degradation in China which, coupled with industrial pressures on the environment, were deemed responsible for catastrophic flooding events in the late 1990s. After these events, China's forest policy underwent a significant reorientation towards ecological conservation and rural development, a process epitomized by the Conversion of Cropland to Forest Program (CCFP). Launched in 1999, the CCFP integrates both socioeconomic and environmental objectives with the aim of reforesting smallholder cropland on sloping lands, while compensating farmers with payments for their lost income. Following 15 years of implementation, it is timely to conduct a comprehensive assessment of the state of knowledge about the CCFP's impacts on human populations and the environment. Methods/design: The primary research question asks "What socioeconomic and environmental effects has the Conversion of Cropland to Forest Program had on human populations and land resources during its first 15 years in China?" We use a theory of change and a Population-Intervention-Comparator-Outcome (PICO) framework to structure our systematic review, where populations of interest consist of both human populations and land resources targeted by the program, while the intervention of interest is the CCFP as defined by its component activities, including compensatory subsidies, skill-training, and enforcement with field checks. Outcomes are defined as both the socioeconomic and environmental impacts of the program. We will conduct a search for relevant English and Chinese language literature on Scopus, Web of Science, CAB Abstracts, AGRIS (FAO), and the China National Knowledge Infrastructure. Search results will be screened for relevance in a two stage process (titles and abstracts, followed by full texts) based on predefined eligibility criteria, and then further assessed for potential sources of bias. Extraction of data from those studies that have passed full-text screening will follow a coding protocol based on the PICO framework, and quantitative and qualitative analyses of the extracted data will be conducted and synthesized. Finally, a narrative report will present the findings of the review, alongside a geographic map illustrating the coverage of included studies compared with the actual implementation area of the CCFP. [ABSTRACT FROM AUTHOR]

The soil seed bank potentially is one of the important components of the regeneration of a wetland. To understand the effects of flooding on the germination of seed banks in wetlands, we simulated three hydrologic regimes in a seed bank germination experiment. Soil samples were collected from four communities in the Nansi Lake wetlands in Shandong Province, China. The temporal dynamics, species abundance, and number of seedlings were determined and analyzed statistically at the species and community levels. The results showed that flooding can delay seed emergence and suppress terrestrial plant emergence. Soil seed banks from different communities exhibited different responses to flooding, highlighting the role of species-specific flooding tolerance. These results also suggest that the species composition of emergent community types in shallow lake shore and humidogene forest characterized by shallow water tables would change drastically after Nansi Lake was impounded as a reservoir for China's South-to-North Water Transfer Project. Finally, based on the temporal dynamics of seed emergence, we suggest that emergence experiments be conducted over a longer period to avoid missing some species in the wetland soil seed bank. [ABSTRACT FROM AUTHOR]

Nonylphenol is an endocrine disruptor with harmful effects including feminization and carcinogenesis on various organisms. This study aims to investigate the distribution and ecological risks of nonylphenol in the Daliao River Estuary, China. Nonylphenol, together with other phenolic endocrine disruptors (bisphenol A, 4- t-butylphenol, 4- t-octylphenol, and 2,4-dichlorophenol), was detected in surface water and sediment on three cruises in May 2009, June 2010, and August 2010, respectively. A large flooding occurred during our sampling campaign in August and its effect on nonylphenol concentrations and fluxes in the estuary was therefore evaluated. The results showed that nonylphenol with a concentration range between 83.6-777 ng l and 1.5-456 ng g dw in surface water and sediment was the most abundant among the phenolic compounds, accounting for 59.1-81.0 and 79.9-92.1 % of the total phenolic concentration in surface water and sediment, respectively. The concentrations recorded in May and June were comparable, whereas those in August were considerably higher, mainly due to the flush of flooding. The flooding also caused a 50 times increase in nonylphenol flux from the estuary into the adjacent Bohai Sea. Nonylphenol concentrations in the estuary have exceeded the threshold level of undesirable effects with a potential risk of harm to local species, especially benthic organisms. [ABSTRACT FROM AUTHOR]

Both flooding and drought are important in determining plant distribution in wetlands. However, the roles of plant's physiological response to flooding and drought in accounting for plant distribution are far from clear. To this end, three typical wetland plants with different distribution patterns (high-elevation species Miscanthus sacchariflorus, low-elevation species Carex brevicuspis and Polygonum hydropiper) in Dongting Lake were treated with three water levels (flooding 25 cm, control 0 cm, drought −25 cm), and relative growth rate (RGR), malondialdehyde (MDA) content, electrolyte leakage and proline content were investigated. The RGR of the three species decreased significantly in both flooding and drought treatments. Compared to the control, the RGR of M. sacchariflorus decreased more in the flooding treatment but less in the drought treatment compared to the other two species. The contents of MDA in the three species increased in both flooding and drought treatments, except for P. hydropiper in the flooding treatment. MDA contents increased more in M. sacchariflorus in the flooding treatment but less in the drought treatment compared to the other two species. Only M. sacchariflorus had a higher electrolyte leakage in the flooding treatment, and drought led to a higher electrolyte leakage in P. hydropiper and C. brevicuspis. Proline content increased 69.2, 66.7 and 39.6 % in P. hydropiper, C. brevicuspis and M. sacchariflorus in the flooding treatment, and increased 44.2, 13.0 and 45.3 % in the drought treatment, respectively. These results suggest that M. sacchariflorus has a higher tolerance to drought but a lower tolerance to flooding than do the other two species, which might be the intrinsic mechanisms accounting for their different distribution patterns. [ABSTRACT FROM AUTHOR]

Heavy metals (Cd, Ni, Cu, Pb, and Zn) and total sulfur (TS) in both surficial sediments and adjacent floodplain topsoils of the Lean River catchment are investigated to comprehend the effects of flooding on heavy metals in soils, the evolution of the quality of sediments, and transfer of sediment metals. The results show that concentrations of metals except for Ni in soils are significantly correlated with those in sediments. At most upstream or downstream locations, sediment metal concentrations are found comparable to those in soils (sed/soil≈1). For Cu at locations close to the Dexing Copper Mine (DCM), flooding brought Cu-poor clays into the floodplain soil system and this leads to sed/soil<1, while at locations adjacent to the Yinshan Lead-zinc Mine (YLM), suspended solids containing high concentrations of iron and magnesium oxide absorb large quantities of dissolved Cd, Pb, and Zn and deposit on the floodplain during flooding (sed/soil>1). In spite of an elevated Cu production of the DCM, a significant decrease in sediment Cu concentrations is found as compared to those 10 years ago. The decrease may be due to the elevated Cu ore utilizing efficiency and the use of a new modern tailing pool. At the location closest to the Yinshan Lead-zinc Mine (YLM), Pb and Zn concentrations increased in recent sediments. In the Lean River, metal contamination in sediments cannot reach the location 60 km downstream of their sources in 2005. [ABSTRACT FROM AUTHOR]

We investigated compositions of plant communities and their abiotic determinants in the Yellow River estuary, China. Along a topographic gradient, we quantified plant compositions and abiotic factors in different vegetation zones, and examined the relationships between plant communities and abiotic factors using canonical correspondence analysis and the effects of vegetation shading using a removal experiment. The relationships between plant communities and abiotic factors differed between high elevations and low elevations. Salinity and flooding oppositely related with distributions of plant communities at low elevations, but they appeared to operate synergically at high elevations. The effects of vegetation shading were found to vary across the topographic gradient, indicating spatial variations in potential positive interactions among plants. These results suggest that spatial variations in determinants of community structure should be addressed in future studies in estuarine and coastal systems, as well as in other natural habitats. [ABSTRACT FROM AUTHOR]

This study assessed pesticide residues in soils, sediments, and vegetables in the Xuan Khe and Hop Ly communes located along the Chau Giang River in the Red River Delta, northern Vietnam. Samples were collected from agricultural areas within and outside of embankments built to prevent flooding. In Xuan Khe, the soils outside of the embankment were more clayey with higher organic matter contents compared with the inside, due to selective deposition during river flooding. Many of the soils contained significant amounts of pesticides including dichlorodiphenyltrichloroethane (DDT), dicofol, isoprothiolane, and metalaxyl although their levels were below the maximum allowable concentration set by the Vietnamese government. The spectrum of DDT derivatives found suggested that the source of DDTs was not contaminated dicofol. Soils in Hop Ly resembled soils in Xuan Khe but were relatively sandy; one field showed appreciable contents of DDT derivatives. The ratios of ( p, p-dichlorodiphenyldichloroethylene + p, p-dichlorodiphenyldichloroethane)/∑DDT in the surface and subsurface soils in Hop Ly were 0.34 and 0.57, suggesting that the DDTs originated from recent application. Pesticide residues in soils were not likely to translocate into vegetable crops, except for metalaxyl. High concentrations of cypermethrins in kohlrabi leaves could be ascribed to foliar deposition. [ABSTRACT FROM AUTHOR]

Sanjiang Plain is the largest freshwater marsh in China, where plant zonation along water-level gradients is a common phenomenon. The aim of this experiment was to identify the role of water level and nutrient availability on plant zonation in the plain. Growth and root morphology of three perennial emergent macrophyte species were investigated by growing in two water levels (0.1 and 10.0 cm, relative to soil surface) and in two levels of nutrient supply (0 and 0.5 g slow-release fertilizer per container). In the plain, Carex lasiocarpa typically occurs at low elevations, Glyceria spiculosa at medial elevations, and Deyeuxia angustifolia at high elevations. The relative growth rate was the highest in C. lasiocarpa and the lowest in D. angustifolia in the 10.0-cm water level. Among the three species, only total biomass of D. angustifolia was affected by water level, and decreased with increasing water level. High nutrient supply led to increased total biomass in C. lasiocarpa and G. spiculosa. High water level led to an increased root diameter in G. spiculosa and a decreased root length in C. lasiocarpa. In the 10.0-cm water level, low nutrient supply led to thinner roots in D. angustifolia, but resulted in an increased specific root length (SRL) in C. lasiocarpa and root diameter in G. spiculosa. Water-level effect on root porosity was only observed in G. spiculosa, and nutrient amendment did not influence root porosity in all the species. These data indicate that both nutrient and water level are important factors regulating plant distribution pattern in the Sanjiang Plain, because both C. lasiocarpa and G. spiculosa are relatively sensitive to nutrient supply whereas D. angustifolia is sensitive to water level. [ABSTRACT FROM AUTHOR]

As climate change becomes increasingly widespread, rapid, and intense, the frequency of heavy rainfall and floods continues to increase. This article establishes a prediction system using feature sets with multiple data dimensions, including meteorological data and socio-economic data. Based on data of historical floods in 31 provinces and municipalities in China from 2006 to 2018, five machine learning methods are compared to predict the direct economic losses. Among them, GBR performs the best with a goodness-of-fit of 90%. Combined with the input-output (IO) model, the indirect economic losses of agriculture to other sectors are calculated, and the total economic losses caused by floods can be predicted effectively by using the GBR-IO model. The model has a strong generalization ability with a minimum requirement of 80 pieces of data. The results of the data show that in China, provinces heavily reliant on agriculture suffered the most with the proportion of direct economic losses to provincial GDP exceeding 1‰. Therefore, some policy implications are provided to assist the government to take timely pre-disaster preventive measures and conduct post-disaster risk management, thereby reducing the economic losses caused by floods. [ABSTRACT FROM AUTHOR]

The article reports on the study of the historical climate variations and climate change in the Brahmaputra basin such as Tibetan plateau (TP), Himalayan belt and the floodplains (FP). The study analyses the historical trends in temperature and precipitation of the TP, FP, and Himalayan belt through a global 100 year monthly high resolution dataset. It shows that precipitation in the basin is determined by the strength by the monsoons. It expresses that El Niño Southern Oscillation teleconnection does not have an important role in the changes in monsoon precipitation. The study also demonstrates the relationship among air temperature, FP, TP, and the strength of the monsoon.