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Guar is a typical legume cash crop native to India. Guar beans are ever-rising in the market share at present. Among them, the guar gum of its seed endosperm has been mainly used in the oil exploration industry. Water-based fracturing fluid can be formulated to increase the permeability of oil-bearing strata during oil production. In addition, guar gum is also widely used in paper making, textiles, food, spices, drugs, as well as mining and metallurgical industries. The nutrient-rich green seeds of guar beans are edible for food vegetables, due to a large amount of protein and a small amount of fat. The plant can be used as fodder and green manure. However, the low supply of guar gum on the market cannot fully meet the broad market space. Only a small number of planting areas of guar beans are suitable for the cultivation of guar beans in the food industry. Among them, Xinjiang located in the northwestern inland arid zone is very similar to the unique geographic conditions for the production and cultivation of guar beans. The temperature and heat conditions are suitable for the origin of guar, rich in the light and heat resources under the soil and water environment, with the high temperature difference between day and night, due to the scarce rainfall and high evaporation. But the relatively small region of guar bean planting still remains so far. Therefore a broad prospect can be expected to optimize the water and nitrogen management for the high crop yield and efficient use of water and nitrogen. This study aims to explore the water and nitrogen mode suitable for drip irrigation of guar beans under film in the Xinjiang area of China. Four irrigation levels were set: W1:1170 m³/hm², W2:1 530 m³/hm², W3:1 890 m³/hm², W4: 2 250 m³/hm²; Two levels of nitrogen application were: N1:30 kg/hm², N2:50 kg/hm². A systematic investigation was made to clarify the effects of water and nitrogen interaction on the growth index, yield, water, and nitrogen use efficiency, as well as the quality of guar bean during drip irrigation under film. The results showed that the coupling effect of water and nitrogen shared a significant effect on the yield, irrigation water use efficiency, and partial factor productivity of nitrogen fertilizer (W3>W4>W2>W1). There was an increase in the plant height, stem diameter, dry matter accumulation, yield, water use efficiency, galactomannan, soluble sugar, and polysaccharide content of Guar bean under the N2 level, compared with the N1 level. Only the partial productivity of nitrogen fertilizer decreased slightly. Principal component and membership function analysis showed that the optimal treatment was achieved in the irrigation amount of 1 890 m³/hm² and the nitrogen application rate of 50 kg/hm²(W3N2). The finding can also provide a theoretical basis to promote the yield, water, and nitrogen use efficiency of Guar bean under mulched drip irrigation. [ABSTRACT FROM AUTHOR]

Water resource shortages have become a national issue in China. Population growth and climate change tend to further aggravate this problem. Water rights trading is an economic means for alleviating the shortages and inefficient utilization of water resources and effectively promoting their optimal allocation. As the strategy choice of both parties of the trading directly affects the efficiency of water rights trading, this paper systematically analyzes the relevant parameters affecting the bilateral strategy choice of water rights trading based on the evolutionary game theory. First, given the impact of the market competition environment on the efficiency of water rights trading, this paper assumes that market competition is the major risk factor leading to the breakdown of negotiations; establishes the income matrix of both sides of water rights trading based on the bargaining model with the risk of breakdown; and analyzes the position, stability, and system evolution mechanism of the equilibrium point under different circumstances. Second, to emphasize the important influence of the initial strategy point on the equilibrium result of the evolutionary game, this paper describes the relative competition conditions according to the number of potential partners on both sides and further determines the initial strategy point of the game system. On this basis, the stability of the bilateral strategy choice is analyzed by using evolutionary game theory. Finally, the case of water rights trading between Zhongning City and Jingneng Power Plant is simulated and analyzed with the help of MATLAB. The results show that the trading water volume, the water resource utilization level of the transferee, and market competition have a significant impact on the transaction price, and: ① The efficiency of water rights trading will be affected when the demand of the transferee for water rights is too low and the water rights saved by the transferor cannot be effectively split. On the contrary, the sharp increase in the comprehensive compensation cost will directly raise the expected price of the transferor and will also affect the efficiency of the water rights trading. ② When the transaction price and other conditions are given, the water use efficiency of the transferee is directly proportional to the convergence speed of the water rights trading game system. ③ When the water use efficiency of the transferee of water rights is high, the price of water rights trading can be appropriately increased to realize the paid use of water resources and ensure the property income of the transferor of water rights. ④ When the transaction price and other conditions are given, the more participants in the water rights trading market, the more conducive it is to the conclusion of water rights trading. [ABSTRACT FROM AUTHOR]

[ Objective]The present paper explored the spatial-temporal characteristics of utilization efficiency of agricultural water under constraints of carbon emission and water pollution in 16 prefectures of Yunnan province from 2010 to 2019, and put forward some suggestions on improving utilization efficiency of agricultural water. [Method] The Super-SBM model, the kernel density estimation method and Malmquist index method were used for the analysis of utilization efficiency of agricultural water in Yunnan province. [ Result] The utilization efficiency of agricultural water in Yunnan province was low, and there was great potential for improvement. There were significant differences among regions, showing a spatial distribution of reduced radiation around the 'Central-Southern Yunnan province T-belt'. The utilization efficiency of agricultural water in Yunnan province had shown an obvious upward trend, with different upward trends in different regions in the past 10 years. The medium and high-level areas had a large growth rate and range while the low-level areas had the opposite. There was a polarization phenomenon in utilization efficiency of agricultural water in Yunnan province. The range of medium and high efficiency zones increased, while low efficiency zones decreased or even disappered. Yunnan province presented the spatial pattern of high utilization efficiency of agricultural water of ' three pillars' in central Yunnan province, southern Yunnan province and western Yunnan province. The degree and scope of the agglomeration in the agglomeration areas continued to increase, ranging from central Yunnan province to western Yunnan province to southern Yunnan province. [ Conclusion] The overall level of utilization efficiency of agricultural water in Yunnan province was low. There were large differences in temporal variation and spatial distribution. Technological progress is the fundamental measure to improve utilization efficiency of agricultural water. Differentiated enhancement measures should be adopted for different prefectures. [ABSTRACT FROM AUTHOR]

In the process of vegetation restoration of mine slope, the slope direction has a great influence on the effect of plant regreening. In this paper, Parthenocissus quinquefolia(L.) Planch brocade was taken as the research object, planting troughs were arranged at the foot of the high and steep bedrock slope facing east, south, west, and north. Parthenocissus quinquefolia(L.) Planch was planted in the planting troughs. The slope heterogeneity and suitability of functional traits of Parthenocissus quinquefolia(L.) Planch leaves were studied by analysis of variance and principal component-membership function evaluation. Partial correlation analysis was used to reveal the effect of climatic factors on the changes of leaf functional traits to understand the adaptability of Parthenocissus quinquefolia(L.) Planch to slope climate change. The results showed that in the characteristics of leaf structure, the order of the leaf dry matter content(LDMC) was as east slope > west slope > north slope > south slope. Leaf water content (LWC) and specific leaf area(SLA) are north slope > east slope > west slope > south slope, leaf thickness(LT) is south slope > east slope = west slope > north slope, and leaf tissue density(LTD) is south slope > west slope > east slope > north slope. In the leaf photosynthetic characteristics, the order of net photosynthetic rate(Pn), stomatal conductivity(Gs), transpiration rate(Tr), and water utilization efficiency(WUE) was as east slope > west slope > north slope > south slope, intercellular CO2 concentration (Ci) was opposite to the order. In the leaf fluorescence characteristics, the initial fluorescence(Fo) on the south slope and est slope were large, and the value on the est slope and the north slope were small. Maximum fluorescence(Fm), PSⅡquantum efficiency (Fv/Fo), and PSⅡ maximum photochemical efficiency(Fv/Fm) were in the order of north slope > east slope > south slope > west slope. The comprehensive order of slope adaptability of Parthenocissus quinquefolia(L.) Planch was as follows: east slope (2.67) > north slope(1.66) > west slope(0.07) > south slope(-1.60). The effects of different climatic factors on the functional characters of Parthenocissus quinquefolia(L.) Planch leaves were different. The structural characteristics of leaves were greatly affected by environmental humidity, followed by photosynthetic radiation. The photosynthetic characteristics of leaves were greatly affected by environmental temperature, followed by photosynthetic radiation. The fluorescence characteristics of leaves were greatly affected by environmental humidity, followed by environmental temperature and water evaporation. From the above results, it can be known that in the environment of high and steep rock, the growth of Parthenocissus quinquefolia(L.) Planch grew the best on the east slope. Under the conditions of high temperature, strong evaporation, and strong photosynthetic radiation, the functional traits of Parthenocissus quinquefolia(L.) Planch leaves showed stress resistance. [ABSTRACT FROM AUTHOR]

In this paper, a two-tier structure method is proposed for the coupling of multiple water sources allocation at the "plane" level with the optimal operation of the reservoir group at the "line-point" level for the river basins. Taking Yongding River basin for example, the rules of multi-sources-based water allocation and operation, including the rules for water supply and water diversion, multi-source water supply strategy and common water supply task allocation strategy are formulated, the model for multiple water sources allocation and optimal operation of reservoir group is established, and the operation schemes under the various scenarios of multi-source water supply and water demand in the basin as well as the water supply benefits from the optimal scheme are analyzed. The results show that: ① In the Yongding River basin, the scenario of combining multi-source water supply system consisting of the local water, water diverted from Yellow River, water from the South- to- North Water Diversion Project and the reclaimed water, with the water conservation is the optimal scheme. ② The guarantee rate of domestic water supply, industrial water supply and ecological water in Sanjiadian Section is greater than 99%, 97% and 96% respectively, with the guarantee rate of water supply in irrigation zones ranging between 76. 7%-90. 2% ( except the upper reaches of Sanggan River). ③ The adoption of multi-source water supply and water conservation strategy can lead to significant improvement of the water supply efficiency for water users and abundance of the ecological water volume of Sanjiadian Section. The method described herein can serve as references for the study on the allocation of multiple water sources and the optimal operation of reservoir groups in a given river basin. [ABSTRACT FROM AUTHOR]

[Objectives] This paper aimed to define the regulation effect of the interaction between density and irrigation volume on yield of machine-harvested cotton with 76 cm equivalent row spacing and promote deep integration between agricultural machinery and technology. [Methods] Through setting three primary processing zones by density[D1, low density, 135 000 plants·hm-2; D2, medium density (CK), 180 000 plants·hm-2; D3, high density, 225 000 plants·hm -2]and three secondary processing zones by irrigation volume 3 150 m³·hm-2[I1, severe shortage (50% of field moisture capacity)], 4 050 m³·hm-2[I2(CK), slight shortage (75% of field moisture capacity)] and 4 950 m³·hm-2[I3, fully irrigated (100% of field moisture capacity)], this paper selected the 'Xinluzhong 88' in Aksu cotton region as the material to study the impact of the interaction between density and irrigation volume on dry matter accumulation and distribution of machine-harvested cotton with 76 cm equivalent row spacing, temporal distribution of cotton boll, yield, and components. [Results]The improvement of cropping density and irrigation volume slowed down the descending rate of leaf-area index after the flowering and boll-forming stage. The dry matter accumulation of groups and quantity of bolls per unit area increased with improvement of the cropping density, but distribution proportion of economic organs and single boll weight declined slightly. Through increasing the irrigation volume, the dry matter accumulation of groups and distribution proportion of economic organs tended to rise and then decline. However, the single boll weight tended to decline with increase of the irrigation volume under the high-density cropping condition. The dry matter fast accumulation of D3I1 was large under the interaction between density and irrigation volume. During the boll opening stage, the high distribution proportion of economic organs of D3I1 promoted the yield of seed cotton and water use efficiency to increase 3.48%-25.93% and 1.14%-43.29% respectively, compared to other treatments. [Conclusions] Under the cropping pattern with 76 cm equivalent row spacing and high-density condition, the severe shortage of irrigation can promote transfer of dry matter accumulation to economic organs and improve the single boll weight, cotton yield and water use efficiency. [ABSTRACT FROM AUTHOR]

Karst landforms are mainly special landscapes formed by carbonate dissolution. They are characterized by calcium abundance, lack of soil resources, and insufficient water resources. The growth and development of vegetation in the karst area is restricted by the bedrock. It is very important to understand the synergistic interaction between vegetation metabolism and geochemistry of carbonate rocks in karst areas to maintain the stability of structure and function of the karst ecosystem. The mechanism and law of interaction between vegetation and rock geochemical background in karst areas from two aspects is expounded in this paper: vegetation community promotes weathering of carbonate rocks and geochemical background restricts vegetation. Through summarizing: ( 1 ) Plants promote the weathering and dissolution of carbonate rocks through physicochemical and biological actions, such as secreting carbonic anhydrase organic matter, improving the water retention performance of rock surface through boring by organisms and accelerating the disintegration of broken rocks through root splitting, thus forming a unique karst geochemical background of drought, high calcium, shallow soil layer and lack of nutrients in the soil layer. (2) With the long-term interaction between plants and the karst environment, plants adapt to environmental stress by adjusting their own structures and physiological functions, and even their unique plant succession rules. The plants that survived eventually evolved into unique karst plants that were drought-resistant, adaptable to high-calcium environments, and able to cope with nutrient deficiencies. Due to the solubility of carbonate rocks, the hydrologic system forms a two-layer spatial structure of surface and underground, which makes it difficult to utilize groundwater resources. As a result, the available water resources of local plants are limited, and are prone to drought stress. The drought resistance of plants adapts to the drought or water shortage environment mainly through physiological and biochemical processes, morphological structure and water use. In the morphological structure of the plant, through the stomatal regulation and the xeric structural characteristics of the leaves, the transpiration water loss of the plant is minimized. Some karst plants can cope with drought stress through physiological and biochemical processes, which can reduce the damage caused by drought stress by increasing the activities of antioxidant enzymes and accumulating osmoregulatory substances through phytochemicals. Karst plants improve water use efficiency and reduce transpiration through different water use methods in the dry season. For example, some plants absorb deep soil, deep bedrock water or groundwater water through developed deep roots, and some plants even use fog water. The adaptability of plants to high calcium is realized through physiological structure and process. In a high calcium environment, karst plants can limit the excess calcium transfer upward by forming calcified roots and keeping the calcium content in plants in a relatively stable state through the regulation of calcium oxalate crystal cells and leaves. Plants can also control the intracellular calcium ion concentration by regulating the calcium pool in vivo and controlling the absorption and transport of calcium. Organic acids and mycorrhiza secreted by roots can help vegetation obtain nutrients in the soil to cope with nutrient deficiency in the soil. The organic acid content secreted by the roots of karst plants is usually higher than that of non - karst plants, and the increase of organic acid content can help plants to absorb trace elements. Arbuscular mycorrhizal fungi (AM) and ectomycorrhizal fungi (ECM) help plants adapt to nutrient deficiency by absorbing mineral nutrients from the soil. (3) The vegetation succession in the karst area is similar to the general stage of vegetation succession in normal landforms, but the vegetation succession in the karst area has the particularity of self - generation. The vegetation succession from the middle to the top of the mountain takes a longer time. Vegetation succession changed physical and chemical properties and soil quality. In the process of succession, soil bulk density gradually decreases, and porosity gradually increases over time. At the same time, soil nutrients accumulate with the positive succession of vegetation. During the positive succession process of karst vegetation, the soil water and fertilizer retention capacity is enhanced, the stability is increased, and the survival probability of species and the species diversity are also increased. The special rock geochemical background in the karst area leads to the obvious changes in the spatial distribution of soil resources. High soil heterogeneity promotes the formation of plant community species diversity. For example, the tropical karst area in Xishuangbanna, Yunnan Province covers an area of 3600km 2, accounting for 19% of the land area. The forest survey results in the karst area show that there are 153 families, 640 genera and 1394 species of vascular plants, accounting for 77. 7% of the total floristic families, 56. 1% of the genera and 37. 9% of the species, respectively. The karst plant community is the result of the long interaction between the plant and the environment, the continuous adaptation to the environment and the growth and reproduction. The karstification of plants, the adaptation mechanism of plants under the typical karst soil environment such as drought, high calcium stress and lack of nutrient elements, as well as the succession characteristics of karst vegetation shown in the adaptation process and the biodiversity of vegetation are a whole interaction. The site growth of vegetation promotes the weathering of carbonate rocks and the formation of soil, creating conditions for their own growth. Meanwhile, soil area and soil thickness are positively correlated with plant diversity. The succession of vegetation changes the physical and chemical properties of soil and improves the quality of soil, and the karstification of carbonate rocks promotes the growth of vegetation. The adaptive mechanism of vegetation affects the distribution and growth of plants and promotes the succession process of plant communities and the formation of plant diversity. Due to the spatial heterogeneity of the karst environment and the diversity of plant habitats, plant diversity in karst areas is manifested as few genera, few species and endemic species. However, the internal relationship between plant diversity and the stability of the community ecosystem, as well as the comparative characteristics with non-karst areas still need to be further studied and explored. [ABSTRACT FROM AUTHOR]

The effects of irrigation on winter wheat yield and water use efficiency (WUE) were mostly explored based on site-based experiments in North China Plain (NCP) region. However, due to the influences of contrasting environmental factors (e.g. climate and soil properties), these results cannot be accurately cross-compared among different studies, resulting in the difficulty to get the generalizable pattern at regional scale. Here meta-analysis was conducted to comprehensively evaluate the effects of irrigation on winter wheat yield and WUE in NCP region, with the observation data of 1876 pairs from 186 field experimental papers totally. The differences of the irrigation effects in different regions, precipitation year types, soil texture, and nitrogen (N) application levels were explored, and the corresponding optimal irrigation amounts for reaching high yield and WUE were ascertained. Results showed that compared with non-irrigation during the winter wheat growing period, irrigation increased the yield of winter wheat in NCP by 32.0%-38.3%, and reduced the WUE by 27.1%-30.1%. The yield increment due to irrigation in the northwest of NCP (39.6%-53.5%) with total precipitation during the winter wheat growing period below 150mm was higher than that in the southeast of NCP (24.3%-27.1%) with total precipitation during the winter wheat growing period higher than 150mm, while the decrease of WUE due to irrigation in northwest of NCP (32.4%-37.5%) was higher than that in the southeast of NCP (22.0%-24.3%). The optimum irrigation amount for high yield and WUE of winter wheat was 150-180mm in the northwest and 120-150mm in the southeast. Specifically, for different precipitation year types, the optimum irrigation amounts were 120-150mm with 2 times during jointing and flowering stages for dry year, during jointing and heading stages for normal year, and during jointing and booting stages for wet year. For different soil texture, irrigation under loamy soil had the highest increases in yield, while clay soil had the lowest decreases in WUE; the optimum irrigation amounts of winter wheat with four different soil texture of sandy soil, loam, clay loam and clay were 60-90mm, 120-150mm, 180-210mm, and 150-180mm, respectively. For different N application levels, N application of 120-240kg.ha-1 led to the highest yield and WUE under the irrigation amounts of 80-140mm, of which the higher yield was obtained under irrigation amounts of 110-140mm, and the higher WUE was obtained under the irrigation amounts of 80-110mm. Collectively, the NCP region can achieve the goals of high yield and WUE when irrigation amount was 120-150mm with 2 times but at different stages during different precipitation year types (i.e. dry year, normal year and wet year). Meanwhile, the combination of loam conditions with the N application of 120-240kg.ha-1 can synergistically improve the yield and water use efficiency of winter wheat. [ABSTRACT FROM AUTHOR]

Climate change and human development have significantly altered the processes of natural water cycling, aggravating the challenge of worldwide water governance. China has initiated a new paradigm of water governance. However, the gap between concept and reality widened due to a lack of appropriate data and methodology. Current water management focuses on limiting the water withdrawals and improving the water use efficiency, and is not yet able to ensure the implementation of the new water governance paradigm. After a thorough study of the advanced development and achievement of water governance policies both at home and abroad, the conclusion has been reached that the total water consumption should be introduced as an additional management indicator to implement a dual control of water withdrawal and consumption. The paper proposes to: (1)Establish water consumption monitoring infrastructure with evapotranspiration remote sensing monitoring as its core component. (2) Implement the rigid water resources constraint by determining available water consumption targets of human activities in the basin, considering water requirements of environmental flow and ecosystem restoration, and establish a cascading system assigning targets to the sectors and/or stakeholders. (3) Implement the water consumption reduction schemes by limiting agricultural planting areas and optimizing ecosystem restoration with indigenous species. It is expected that the proposed approaches will effectively ensure the implementation of China′s new water resources governance paradigm with innovative data, methods, and measures. [ABSTRACT FROM AUTHOR]

This paper summarizes the evolution of engineering water conservancy, environment water conservancy, resources water conservancy and ecological water conservancy in our country. Moreover, the research progress, developing tendency and characteristics of ecological water conservancy worldwide is explored. Corresponding results demonstrate that ecological water conservancy is a way of water resources utilization in the time of ecological civilization, which serves the sustainable development of human society through implementing water conservancy and developing economy with the gist of respecting and protecting ecological environment. Present paper elucidates the connotation, definition and development mode of generalized ecological water conservancy, and proposes following conclusions and academic viewpoints; CD Generalized ecological water conservancy explores specific measures and ways in ecological water conservancy to meet the demands of human society and healthy water ecosystem through selecting water resources and water cycle operation as primary ecological elements from the multiple perspectives of energy exchange, biological links, structural balance and cycle and transformation in watershed ecosystem. CZ) This paper presents engineering and ecological security system for the full- process and lifecycle ( i. e. planning and design, construction management and ecological regulation) of water conservancy project. In particular, ecological regulation is incorporated into the full-service period of water conservancy project. Furthermore, we highlight that basin- scale ecological regulation is the most effective measure to protect and restore ecosystem in the "post-dam era". ® We suggest dominating the spatial dimension of ecological water conservancy, promoting optimal design of ecological- productionliving spaces, ensuring the reasonable allocation of ecological- production- living water use, and optimizing the relationship among general life, production and ecology from the perspective of ecological environment, social economy and water cycle regulation in the system of planning and governance of territorial space to realize ecology protection and high- quality development of society and further promoting the innovative development of ecological water conservancy. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to improve the fruit quality, yield and water use efficiency of cherry tomato cultivated in solar greenhouse substrate. [Method] 'Jinfei' was used as the experimental material, and a completely randomized block design was adopted. Under the condition of split root irrigation, the total irrigation amount of cherry tomato in growth period was kept constant, the designed irrigation frequency was once a day (Dl), once every two days (D2) and once every three days (D3), the alternate frequency was that one side was irrigated once (Tl), twice (T2) and three times (TI), and then the other side was irrigated alternately, and a total of 9 treatments were used to analyze the effects of different irrigation frequency and alternate frequency on the quality, yield and water use efficiency of cherry tomato. [Result] The different irrigation frequency and alternate frequency had significant effects on the biomass accumulation of cherry tomato. The dry matter accumulation of DlTI was the highest, 249. 28 g/plant, but had no significant effect on the root shoot ratio;Reducing irrigation frequency could weaken the photosynthetic activity of plants and reduce the ability of leaves to capture light energy; The vitamin C content of D2 TI was the highest, which was significantly increased by 4. 49% to 191. 37 mg / kg compared with Dl Tl ; The contents of soluble solids and organic acids of Dl TI were not significantly different from those of D 1 Tl, but the contents of soluble sugar and sugar acid of Dl Tl were significantly increased by 20. 25% and 21. 33%, respectively;The average fruit weight, yield and water use efficiency of DlTI were significantly increased by 17. 76%, 9. 85% and 9. 85% compared with that of DlTl, respectively. [Conclusion]The comprehensive evaluation of treatment DlTI was the best, and it was the best irrigation strategy under alternate root zone irrigation. [ABSTRACT FROM AUTHOR]

[Objective] The objective of the paper is to provide a reference for screening high-yield and good-quality tea cultivars suitable for planting and popularization in Guizhou. [Method] By using Li-6400XT portable photosynthetic system and ethanol extraction-colorimetry, taking Furling White Tea as the control, the leaf photosynthetic physiological indexes, leaf functional traits and their correlations of 15 tea cultivars (lines) cultivated in the same habitat were measured to determine the photosynthetic potential of 15 tea cultivars (lines). [Result] There were differences among photosynthetic physiological indexes, photosynthetic pigment content and leaf functional traits of 15 tea cultivars (lines). Mabianlv, Zhenong 901, Chuannonghuangyazao and Chuanmu 28 had higher photosynthetic characteristics, and photosynthetic efficiency was stronger, P n was 8. 89 - 9. 81 f.LmoV (m2 • s), which had higher high-yield potential compared with other 11 tea cultivars (lines). Chuannonghuangyazao was an etiolation cultivar. Its photosynthetic pigment content was lower, and was equivalent to Furling White Tea (CK). P n, SLA and WUE were higher. The cultivar was featured with higher etiolation specificity, photosynthetic capacity and water use efficiency, which had better cultivation and utilization prospects. Zhongxuan 10, Zhongcha 112 and Baojing Golden Tea had higher WUE, respectively 3. 77 - 3. 91 f.LmoVmmol, and lower transpiration rate[2. 08 - 2. 20 mmoV (m2 • s) J. The three cultivars (lines) had stronger drought resistance potential, which could be researched on resistance indexes deeply. [Conclusion] From the perspective of photosynthetic characteristics, Mabianlv, Zhenong 901, Chuannonghuangyazao and Chuanmu 28 have higher photosynthetic capacity, which can be cultivated and popularized in Guizhou. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the crop coefficient and irrigation system of jujube with different irrigation quota under drip irrigation in the arid oasis area of Southern Xinjiang. [Method] Using the principle of water balance and penman-Monteith formula, the water consumption of jujube was calculated and the crop coefficients of jujube under different irrigation quotas were determined. Four irrigation quotas were set in the experiment, and each quota was repeated three times. [Result] When the irrigation quota was 420 m3 / 667 m², the difference between the next irrigation and this one was 0. 24%, and the soil moisture content was basically the same before the two irrigations, the consumption of jujube and the evaporation of field soil were basically equal to the irrigation water, and the irrigation water was more reasonable. The total water consumption of jujube with different irrigation quota during the growth period ranged from 598. 46 - 714. 08 mm, and the water consumption rule during the whole growth period was as follows: Germination and Spreading stage < Fruit Ripening Stage < Fruit Swelling Stage < Flowering and Fruiting Stage. Water consumption modulus 68. 36% - 72. 91 % at Flowering and Fruiting Stage and Germination and Spreading Stage. The reference crop evapotranspiration ET 0 increased first and then decreased, showing a parabolic change. The crop coefficient of Jujube was 0. 33 - 0. 39 in Germination and Spreading Stage, 0. 85 - 1. 07 in Flowering and Fruiting Stage, 0. 80 - 0. 94 in Fruit Swelling Stage and 0. 44 - 0. 47 in Fruit Ripening Stage. [Conclusion] The W2 irrigation treatment was more suitable for jujube growth and development, with the highest yield (516. 81 kg/667 m²) and the highest water use efficiency (1. 23 kg m¹). The corresponding crop coefficients were 0. 35 in the Germination and Spreading Stage, 0. 93 in the Flowering and Fruiting Stage, 0. 86 in the Fruit Swelling Stage and 0. 46 in the Fruit Ripening Stage. Considering the irrigation and yield benefit, the best irrigation system for jujube in the whole growth period was 420 m1 /667 m², with 9 irrigation times. [ABSTRACT FROM AUTHOR]

Affected by global warming in southwest karst area and monsoon climate, the annual precipitation in southwest karst area and its distribution between seasons have changed obviously, and the frequency and duration of non-rain period are increasing. In addition, karst woody plants face more serious seasonal and geological droughts due to the strong weathering of bedrock and poor water storage capacity. This paper discusses how karst plants adapt to geological and seasonal drought by analyzing their structural characters and physiological regulation by referring to relevant literatures. The results indicate that like plants in arid and semi-arid areas, karst woody plants have two strategies to cope with drought: drought resistance and drought avoidance. Drought-resistant plants generally have some drought-resistant characteristics, such as small specific leaf area, succulent mesophyll, well-developed water storage tissue and high cell fluid concentration and so on, and can adapt to drought by increasing wood density, enhancing vessel anti-embolism and improving water use efficiency. Drought-avoidant plants can reduce water loss by small and dense stomata and leaf veins, developed superficial fur, palisade tissue and vascular sheath, and adapt to drought by defoliation, deep root absorption of deep water and early stomatal closure mediated by Abscisic acid(ABA). Although some progress has been made in the research on karst plants adapting to drought through morphological structure and physiological regulation, there are still some problems to be solved urgently, such as the study of bedrock water condition in karst area and its contribution to plants, the root structure and biomass allocation of karst woody plants, the relationship between tree configuration and drought adaptation and synergistic relationship between rhizosphere microorganisms and woody plants. At the same time explore how to apply the results of physiological and ecological adaptation of karst woody plants to drought in production practice, and scientifically guide the control and ecological restoration of rocky desertification. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of different concentrations and forms of nitrogen on the phenotype and photosynthetic fluorescence of Meconopsis rudis seedlings, and to select the most suitable nitrogen forms and concentrations for the growth of Meconopsis rudis seedlings. [ Method] The half year seedlings were fertilized, including two concentrations and three nitrogen forms. The phenotypic parameters, chlorophyll fluorescence, photosynthetic index and soil nitrogen content were measured after 20 days of each fertilization. [Result] (i)The plant height and dry weight of seedlings were increased by applying nitrogen fenilizer, the treatment of 4 g · L -1 ammonium nitrate increased the plant height and dry weight most significantly (P <0. 05). (ii) Nitrogen application could effectively improve the apparent electron transfer rate (ETR), maximum fluorescence (Fm), maximum photochemical efficiency (Fv/Fm), acrual photochemical efficiency (Y II), photochemical quenching (qp), net photosynthetic rate (Pn), stomatal conductance (G8), transpiration rate (Tr), water use efficiency (WUE), reduce non photochemical quenching (NPQ) and intercellular CO2 concentration (Ci), the treatment of 2 g· L -1 ammonium nitrate increased the net photosynthetic rate most significantly (P < 0. 05), and the treatment of 4 g • L -1 nitrogen hindered the photosynthesis of seedlings. (iii) Nitrogen application could effectively improve the soil nitrogen content of seedlings, among which the treatment of 4 g · L -1 ammonium nitrate was the most significant (P < 0. 05). [Conclusion] The most suitable nitrogen form for the seeding growth of Meconopsis rudis was ammonium nitrate nitrogen. The most suitable nitrogen concentration for the seedling growth of Meconopsis rudis was the treatment of 2 g · L -1 and the treatment of 4 g· L -1. Among them, 4 g • L -1 ammonium nitrate nitrogen was more conducive to the increase of plant height, dry weight and soil nitrogen content, and 2 g • L -1 ammonium nitrate nitrogen was more conducive to the increase of photosynthetic capacity of the seedling. [ABSTRACT FROM AUTHOR]

【Objective】The purpose of this paper is to investigate the effects of soil moisture on photosynthesis of winterly tobacco during vigorous growing stage. 【Method】The soil moisture content was controlled by weighing method and the water gradient was set to 4, daily dynamics of photosynthetic characteristics, stomatal characteristics and chlorophyll of winterly tobacco under different soil moisture conditions were determined. 【Result】（i）The daily dynamics of net photosynthetic and transpiration rate of winterly tobacco leaves under different soil moisture levels were in the form of double peaks curve and single peak curves. The mean daily values of net photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 concentration of winterly tobacco were decreased with the soil moisture reduced, and the diurnal processes were quite different under different soil moisture.（ii）The main limiting factor affecting photosynthesis and transpiration of winterly tobacco under the condition of sufficient water was photosynthetically active radiation, but stomatal conductance was the main limiting factor in water deficient environment.（iii）Water use efficiency of winterly tobacco would be improved in moderate drought conditions, and it was higher in the morning than in the afternoon.（iv）The effect of soil moisture on stomatal characteristics of leaf was obvious. The size and area of the stomata was decrescent with the water reduced, but the stomatal density increased.（v）The effect of soil water on photosynthetic pigments in leaves was obvious, photosynthetic pigment content was decreased with the soil moisture reduced, the decrease of chlorophyll b was greater than that of chlorophyll a, and the reduction in carotenoids was minimal. 【Conclusion】Winterly tobacco is very sensitive to soil moisture during vigorous growing stage, lack of water leads to impaired leaf function and decreased photosynthesis, in order to ensure the growth and development of winterly tobacco flourishing, the soil relative water content should be kept above 65 %. [ABSTRACT FROM AUTHOR]

Water and fertilizer are indispensable inputs to crop production in modern agriculture. Drought, water shortage and low efficient utilization of water have posed a great challenge on agricultural production and food security in China. New fertilizers with dual functions of water retention and slow release become significant to enhance the utilization efficiency of water, and thereby to ensure the sustainable development of agriculture. Therefore, previous studies on the new fertilizers have drawn much attention in water and fertilizer technology in recent years. This paper explores the preparation method of a novel water-retaining material that incorporated with nano-SiO2 for the slow-release fertilizer with water retention properties. A P(AA-AM)/SiO2 water-retaining composite was fabricated by in-situ polymerization in aqueous solution using acrylic acid (AA) and acrylamide (AM) as raw materials. A water-retaining slow-release fertilizer was then produced by the double-layer coating process. The mass ratio of acrylic acid (AA) and acrylamide (AM) was set as 3.5:1 to synthesize water-retaining materials. The initiator (potassium persulfate and sodium sulfite), crosslinking agent (N, N-methylenebisacrylamide), plasticizer (glycerol), and nano-SiO2 were added by 1%, 0.04%, 15%, and 2% in monomer mass, respectively. A drum coating process was selected to prepare the water-retaining slow-releasing fertilizer, where the inner coating layer was made of polyurethane, with the mass ratio of coating materials to the inner core of 3%, whereas the outer coating layer was P(AA-AM)/SiO2 water-retaining composite material, with a mass ratio to the core of 27%. Fourier Infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetry (TG) were used to characterize the microstructure, morphology and thermal stability of water-retaining materials. A filtration was selected to determine the water absorption of water-retaining material. Soil culture experiment was used to investigate the capacity of water-retaining and water-holding in the fabricated fertilizer. A water immersion method was utilized to explore nitrogen release properties of fertilizer at the temperature of 25℃. The results showed that the water absorption rates of composite materials with nano-SiO2 in deionized water and 0.9% NaCl aqueous solution were 152% and 87% higher than those of only P(AA-AM) materials, while the thermal stability was also significantly improved. SEM images and FTIR analysis indicated that nanoparticles of SiO2 were evenly dispersed into the P(AA-AM) composites, while the silicon hydroxyl groups on the surface of SiO2 increased the cross-linking density of water-retaining materials. Compared with the slow-release fertilizer without water-retaining layer, the water absorption rate and retention rate of slow-release fertilizer with water-retaining layer (after 25 days of incubation) increased by 25.5% and 47.2%, respectively, indicating the releasing duration of fertilizer was extended from 60 days to 72 days. The preparation method of water-retaining composite material that incorporated with nano-SiO2 and water-retaining slow-release fertilizers can provide excellent properties of water absorption and retaining, as well a high performance of slow release in soil. A mechanism of water-retaining was proposed to clarify the slow release of nutrients in the water-retaining material and water-retaining slow-release fertilizers. The findings can offer new insights into high efficiency fertilizers to enhance the utilization efficiency of water and fertilizers. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to determine the appropriate soil water potential range for Crimson seedless grape after fruit setting and provide a theoretical basis for irrigation in production practice. [ Method] This research studied the effects of different soil water potentials on photosynthetic performance, fruit traits, yield and quality after fruit setting,3-year-old Crimson seedless grape was as test material.[Result] Increased soil water potential could promote the net photosynthetic rate (Pn) of leaves and delay the decline of the net photosynthetic rate with time, could increase the openness of leaf stomata and transpiration of water while the treads of stomatal conductance (Gs) and transpiration rate (Tr) were basically the same, could increase the water use efficiency (WUE) and slow down the decline of water use efficiency, in which the WUE of T1 ,T2 and T3 treatments increased first and then decreased and reached the highest at 40 days after fruit setting. Improved the soil water potential could increase the vertical and transverse diameter of the fruit, increase the single seed weight and single panicle weight, provide the single plant yield and the yield, in which the yield of T1 ,T2 and T3 treatment were higher 20.60% ,31.71 % and 43. 02 % than CK treatment, respectively, among them, the T3 treatment yield reached 150 450 kg/per hm2. It could decrease the dry weight and soluble solids of fruit with the increase soil water potential, in which the dry weight of fruit of T1 ,T2 and T3 treatment decreased by 3.85 % ,10.67 % and 14.09 % . The fruit hardness of T2 and T3 treatments decreased significantly. [Conclusion ] When the soil water potential keeps-40 - - 110 kpa, it can not only promote the photosynthesis of the leaves of Crimson seedless grape after fruit setting, improve the water use efficiency, but also stabilize the fruit yield and improve the fruit quality. [ABSTRACT FROM AUTHOR]

Water Use Efficiency (WUE) refers to the ratio of water used in plant metabolism over water lost in evapotranspiration, indicating carbon-water coupling in terrestrial ecosystem and its response to global change. It is of great significance to clarify the long-term variation characteristics and influencing factors of WUE for the study of carbon and water cycles and the rational utilization of water resources. This study aims to estimate the vegetation WUE of a research site, particularly on the annual and interannual variation characteristics of WUE, and to establish the response relationship between WUE and key meteorological factors. The data used in this paper mainly include the flux and meteorological information from eight sites in China from January 2003 to December 2010. Unified quality control and interpolation methods were then used to pre-process the flux data. The daily flux and meteorological data were combined into 8-day data sets in each site. Pearson coefficient was used to analyze the correlation between vegetation WUE and Gross Primary Productivity (GPP), ET, average temperature, precipitation, and relative humidity factors. The characteristics and influencing factors of WUE were analyzed and compared in different ecosystem. The results showed that: 1)WUE fluctuated greatly in the whole year without obvious regularity in Qianyanzhou, Xishuangbanna and Dinghushan sites which locate in the tropical monsoon climate region, while WUE showed obvious seasonal variation characteristics in the other five sites, all of which increased significantly from April to July, and reached the maximum during the peak period (July to August), and then WUE decreased gradually from August to October. From November to February of the following year, WUE reached zero. 2) From 2003 to 2010, the annual WUE of alpine meadow (Damxung) was the lowest (0.18 g/kg), whereas, that of tropical rainforest (Xishuangbanna) was the highest (4.20 g/kg). The WUE increased annually in the grassland (Inner Mongolia), broad-leaved evergreen forest (Dinghu Mountain), farmland (Yucheng), alpine meadow (Damxung), and alpine meadow (Haibei), whereas, the decreasing trend occurred in the coniferous forest (Qianyanzhou), tropical rainforest (Xishuangbanna), deciduous broad-leaved and coniferous mixed forests (Changbai Mountain). 3) In the 8-day time scale, there was positively correlation between temperature and WUE in alpine meadow, farmland and grassland ecosystem, whereas there was the negatively correlation between temperature and WUE in forest ecosystem. And the negative correlation between WUE and temperature in coniferous forest ecosystem (R=-0.607, P<0.01) was higher than that in evergreen broad-leaved forest and coniferous broad-leaved mixed forest ecosystem. Compared with forest and farmland ecosystem, WUE in alpine meadow and grassland ecosystem had a higher correlation with relative humidity and precipitation; 4) In different ecosystem, the various approaches were proposed to enhance WUE of terrestrial ecosystem for the sustainable development of agriculture, forestry and animal husbandry. Soil management regulation and canopy pruning can improve water use efficiency in the case of forest ecosystem. In farmland ecosystem, water use efficiency can be elevated from irrigation mode and crop breeding. In alpine meadow and grassland ecosystem, man-made grass, rest grazing and area rotation grazing can be used to enhance grassland carbon sink, further to improve water use efficiency. The findings can provide promising potentials to alleviate water shortage against the background of global warming. [ABSTRACT FROM AUTHOR]

[Objective】The present paper aimed to study the effects of different moisture treatments on soil water and salt changes and yield of mechanically harvested cotton during boll stage. ' Method (The experimental plot was used in the key laboratory test base of modem water¬saving irrigation corpus of Shihezi university and the water-saving irrigation test station of Shihezi university. Three water gradients were set up by pit test method, and each treatment was repeated three times. At the end of each growth period, the indexes of soil water content, soil salt content and yield were determined, and the effects of diferent water treatments on soil water and salt change and yield of mechanically har¬ vested cotton were analyzed. ' Result】 The results showed that in W2 (the lower limit of bud period was 60 ' , the lower limit of flowering and boiling period was 70 ' ), the water holding capacity of 0 - 60 cmsoil layer in the root layer of water treatment could reach 63. 28 ', which was suitable for crop growth. The range and the salt leaching effect were ideal, forming a desalting desalination zone, and the cotton field yield wa 5482.38 kghm2 , which wa 12.07 ' -30.39 ' higher than otlier treatments, and the water use efficiency wa 1.30 kgm3, which wa also the best. ' Conclusion 】The effects of different water treatments on the change of water and salt and cotton yield were significant, water treatment of W2 (lower limit of bud stage was 60 lower limit of flowering and boll stage was 70 ') was a more reasonable water control strategy [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to analyze the effect of water regulation on the growth and development of rice and irrigation water use efficiency. 【Method】Three water gradients were set at tillering stage to control water content. At the end of each growth period, the indexes were sampled and measured. 【Result】Water regulation at tillering stage had significant effect on rice growth and irrigation water use efficiency under two cultivation methods. W1 and W2 treatments had little effect on rice plant height, and W3 treatment reduced plant height seriously under water stress. Water regulation at tillering stage has obvious influence on the final tiller number, which shows that the average number of tillers under mulching cultivation is 17.44 per hole, and the average number of tillers under bare land cultivation is 17.60 per hole. W2 treatment can maintain a higher leaf area at the later growth stage, which is more conducive to the accumulation of photosynthetic products and the formation of final yield of rice. Under the condition of film mulching and bare land cultivation, the utilization rate of irrigation water of W2 treatment was the highest, which was 0.64 and 0.46 kg/m~3 respectively. 【Conclusion】Appropriate water stress at tillering stage of drip irrigation rice is beneficial to rice growth and development and then to increase yield. From the perspective of drip irrigation rice to improve irrigation water use efficiency and yield, W2 water treatment of drip irrigation rice film mulching cultivation mode can be used as a more appropriate control measure based on the experimental conditions. [ABSTRACT FROM AUTHOR]

Xiong'an New Area is a millennium plan and a national event. Water shortage and water pollution have become the main problems which restrict its development. Different from the existing research on Xiong'an strategic development interpretation and resource profile description, this paper combines with scenario analysis and directional distance function models so as to show the water resources utilization efficiency and water saving potential development landscape and path of different scenarios in 2035 for the first time and it is innovatively based on the development of Shenzhen. The research shows that Xiong'an presents a change from low-efficiency zone to high-efficiency zone to high-efficiency zone in the Business as Usual, Starting Process and Construction Completion scenarios from the perspective of utilization efficiency. From the perspective of water saving potential, the reduction of efficiency improvement space and the increase in metatechnology ratios indicate that water saving potential of Xiong'an has been fully explored. Avoiding direct sewage discharge, developing sewage treatment technology actively and optimizing the industrial structure of the Xiong'an New Area are effective ways to promote the utilization efficiency of water resources, which is also an important guarantee for Xiong'an to realize green ecological development. [ABSTRACT FROM AUTHOR]

There is an obvious gap between China's current irrigation water use efficiency and the world's advanced level for that of China is only 0.50, whereas that of world's advanced level reaches 0.7-0.8. Therefore, saving water resources, improving agricultural irrigation water efficiency, and ensuring the irrigation efficiency will be a long-term strategic task in the future of China. The purpose of this paper was to make a comprehensive evaluation for water use efficiency of Yellow River irrigation area based on flow-tracing and multiple weights method. In order to make a good comprehensive evaluation for water using efficiency, an open index-evaluation system including 19 deterministic index and 3 sub-systems based on irrigation flow-tracing method. Then, the improved fuzzy evaluation model was constructed based on multiple layer-weight determination method by making use of multi-objective and multi-level system. In the first layer (input layer), the index weight was confirmed by calculating entropy-weight-vector, and in the second layer (criterion layer), the sub-system weight was confirmed by the entropy-weight-vector method, equal-weight method and experience weight method, respectively for multi-layer weights. Finally, obtaining data and comparing different weights from the evaluation results was carried out by the fuzzy evaluation model. The paper took Sanyizhai Irrigation Area in lower reaches of the Yellow River as a case study. Sanyizhai Irrigation Area is located in the eastern plain of Henan Province (34°52N, 144°44E), north of the Yellow River. Sanyizhai Irrigation Area was founded in 1958, and it involves 18 counties scattered in Kaifeng, Shangqiu and Heze in Henan Province, and Shandong Provinces as well. Up to now, the water-diverting capacity of Sanyizhai Irrigation Area is about 150 m3/s, and irrigation area covers 9 counties(districts) mainly in the eastern part of Henan province, that is: Kaifeng, Lankao and Qi counties of Kaifeng City, Minquan County, Ningling County, Suiyang District, Liangyuan District, Sui County and Yucheng County of Shangqiu City respectively. The total land area of Sanyizhai Irrigation Area reaches 4 344.2 km2 and the total cultivated area is 2 701.42 km2. The paper took 10 years data from 2005 to 2014 of Sanyizhai Irrigation Area as a case study to make a comprehensive evaluation for water use efficiency. The 3 kinds of weight was used for the calculation. The results showed that: the first entropy-weight-vector weight was 0.307, 0.348, 0.345, the second equal-weight was 0.333, 0.333, 0.334, and the third subjective weight was 0.400, 0.200, 0.400. The evaluation result presented a general identical trend and showed that weight-influence was very limited for the evaluation result. According to the evaluation result, the irrigation water effect in 2013 was optimal among 10 years with average value 0.993 by comprehensive evaluation. Meanwhile, this evaluation results were in conformity with the actual situation of Sanyizhai Irrigation Area. In 2013 the rainfall and groundwater is relatively small, whereas the practical diverted irrigation intake and irrigation area has kept high level, which has ensured irrigation effect of and crop-harvest. According to the evaluation value of second layer, the dynamic variation process about engineering factors and management factors could be seen clearly, which showed that it kept a low-level development before 2007 and entered into a higher level development after 2009, so it could help us find the existing problems in irrigation process and provides data basis and technical support for the scientific planning and sustainable development of Yellow River Irrigation Area. [ABSTRACT FROM AUTHOR]

At present, North China faces serious groundwater overmining problem. In the action plan of comprehensive control of groundwater overmining in North China, it is clearly proposed to strengthen agricultural water saving, and adjust the structure of agricultural planting. Farmers' cognition of water saving irrigation technology is closely related to water saving effect. This paper takes the survey of 269 farmers in Guyuan county, Zhangjiakou city, Hebei province as a sample, uses structural equation model to explore intrinsic mechanism of farmers' cognition of water saving irrigation technology. Results show that, the path of personal characteristics of farmers, characteristics of household production, characteristics of policy advocacy, farmer cognition of water resources scarcity are 0.186, 0.157, 0.469 and 0.200. respectively. It is indicated that water saving irrigation technology subsidy, technical training and visiting high efficiency water saving demonstration area are effective in improving farmers' cognition of water saving irrigation technology. Therefore, on the basis of reliance on government technical financial support, we should find out the farmers' cognition differences in water saving irrigation techniques, and perfect the publicity system of water saving irrigation technology so as to enhance farmers' enthusiasm to use water saving irrigation technology in North China. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed lo clarify the appropriate drip irrigation quota for topping-mature period of flue-cured tobacco. [Method] A field experiment was carried out to study the ellects of five different drip irrigation quotas (0.0, 10.5, 17. 5, 24.5 and 31.5 mm) on the growth, NPK and water utilization efficiency of due-cured tobacco. [Result] The results showed that the best agronomic traits, the largest biomass of tobacco stem and leal, the highest N and irrigation water utilization rate, and the most coordinated potassium chlorine ratio and nitrogen alkali ratio of tobacco leaves were all observed in die treatment of 24.5 mm. Compared with other treatments, in the treatment of 24.5 mm, the biomass of tobacco stem and leal increased by 4.7%-16.4% and 3.7% - 18.3 %; N and irrigation water utilization rate increased by 3.8-18.3 percentage points and 0.9% —9.4%; potassium chlorine ratio of middle tobacco leal increased bv 32. 1 % , and nitrogen alkali ratio decreased by 32. 4 % , respectively. [Conclusion] This study shows that, 24. 5 mm is an appropriate drip irrigation quota for the topping-mature period of flue-cured tobacco in die region. [ABSTRACT FROM AUTHOR]

In recent years, China's industrial water consumption accounts for about 20% to 30% of all water use. Improving industrial water efficiency and saving use of water resources have become one of the important issues affecting the sustainable development of China's national economy. Based on the network SBM-DEA model and GML index, this paper studies the industrial water use efficiency of each province in China from 2007 to 2015. The results show that: (1) From the annual average, the production stage is at the forefront compared with the sewage treatment stage. There are more provinces at the forefront, and the gap between provinces and frontiers is relatively small. Industrial water use efficiency is high in the production stages of Beijing, Tianjin, Inner Mongolia, Shandong, Guangdong, Hainan, but the efficiency of sewage treatment is low; For Liaoning, Jilin, Anhui, Fujian, Jiangxi, Hubei, Hunan, Guangxi, Guizhou, Yunnan, Qinghai, the efficiency value is lower in the production stage, but the efficiency value in the sewage treatment stage is higher. This is because there are differences in the requirements for sewage treatment in different provinces of China, or even the same requirements, the implementation of different local policies is not the same, and some provinces (such as Beijing) have higher requirements for sewage treatment and policy implementation than other provinces. (2) From the geometric mean of each time period, the GML index value of most provinces in the network and sewage treatment stage is less than 1, but the GML index value in the production stage is greater than 1. It can be seen from the average of 30 provinces that both the EC index and the BPC index in the production stage have improved (greater than 1), but the EC index and BPC index in the network and sewage treatment stages have decreased (less than 1). Therefore, to enhance the industrial water efficiency in the production stage, it is necessary to increase the treatment of industrial wastewater, improve the efficiency of the sewage treatment stage, and raise the awareness of industrial production and pollution control, especially in Beijing, Tianjin, Inner Mongolia, Shandong, Guangdong, and Hainan with low sewage treatment efficiency. [ABSTRACT FROM AUTHOR]

A suitable channel section cannot only increase flow capacity of channel, improve efficiency of water resources, and reduce water leakage loss, but also decrease construction cost. This paper proposed a channel section with a horizontal bottom and catenary sides (HBC). The HBC section, on one hand, provided a larger flow capacity, lesser-sharp angles of stress concentration, less leakage, better slope stability and frost heave resistance than trapezoids and rectangles sections. On the other hand, it had lots of advantages of horizontal bottom sections, such as simpler construction, easier leveling and compaction of the foundation, and lesser construction cost. The most important advantage of this section was that the horizontal bottom and sides could be built with different materials or thickness for decreasing the construction cost or other purposes. The shape function for HBC was defined. The formulas for the flow area, wetted perimeter, and water surface width were presented. A simpler iterative algorithm for calculation of the normal depth was developed. The iterative convergence by this algorithm was evidenced. Comparisons showed that this simpler iterative algorithm was better than classic Newton iterative algorithm. The optimal model of the best hydraulic section of HBC was built. The general differential equations for all the sections having horizontal bottomed and curve sides were derived. The best hydraulic section of HBC channel was obtained according to Lagrange multiplier method and its characteristics were presented including shape factor, ratio of horizontal bottom width to shape factor etc. The results showed that the following optimum parameters were constant for the best hydraulic HBC section: bottom width to water depth, water surface width to depth, bottom width to shape factor, water surface width to shape factor, shape factor to water depth equals. The ratio of water surface width for catenary part to shape factor equaled 3.602, the ratio of bottom width to shape factor equaled 0.855, the ratio of bottom width to water depth equaled 0.405, and the ratio of shape factor to water depth equaled 0.474, and the ratio of total water surface width to water depth equaled 2.112. Various explicit formulae to calculate the normal depth, critical depth, shape factor, flow area, wetted perimeter and water surface width of the HBC section were derived for the best hydraulic section for HBC channel. These formulas should make the design of the HBC section easier and promote its practical applications. The optimum parameters of the best hydraulic section for existing horizontal bottom (HB) sections, such as trapezoidal, rectangle, horizontal bottomed parabolic, and horizontal bottomed semi-cubic parabolic were derived. The comparison results showed that the HBC section had larger discharge than those of existing horizontal bottom (HB) sections under the same conditions. In addition, the flow area, wetted perimeter, and water surface of the HBC section were the smallest, which means that earthwork cost, lining cost and land expropriation cost are all decreased, which means HBC section is more economical. Comparison with classic catenary section showed that the discharge of the HBC was larger than that of the classic catenary section under the same conditions. The flow area, wetted perimeter and water surface of the HBC were smaller than these of the classic catenary section, which means the HBC section has better hydraulic characteristics. Its economy was also superior to the traditional catenary section. The results were verified by examples. The proposed section should enrich existing types of open channel sections. The research provides a new practical and flexible channel section for channel design and theoretical support for horizontal-bottom catenary channel design and applications. [ABSTRACT FROM AUTHOR]

Water- carbon nexus is one of the important research fields of regional sustainable development. Studies on industrial carbon and water footprint efficiency from the perspective of water- carbon coupling not only help reveal the impact mechanism of the resource consumption intensity and efficiency on industrial carbon emissions, but also have great significant practical meanings for reducing water and carbon emissions in regional industrial transformation under the background of globalization. By the method of input-output analysis, input- output table of Henan in 2012 and industrial water and energy consumption data were applied to discuss industrial carbon and water footprint efficiency in this paper. The conclusions are as follows: (1) Carbon and water footprints of different industries are unmatched. The agricultural water footprint is the largest, which is 2333 times of the water footprint of lumbering. The carbon footprint of extractive industry is the largest, which is 273 times of food industry. (2) There are obvious differences among industrial water and carbon footprint efficiency. In general, the water/carbon footprint efficiency is lower in the industries with higher water/carbon footprint. (3) The different water/carbon footprint efficiency among different industries were mainly influenced by industry attribute, water and carbon consumption intensity, energy structure, technological level and relationship between industries, etc. (4) In the future, Henan province should make differentiated water-saving and carbon emission reduction policies in industrial development by combining the characteristics of different industries and the water- energy nexus, strengthening institutional constraint and legal supervision, promoting water and energy efficiency of enterprises, and enhancing regional adaptation and mitigation capacity under climate change. [ABSTRACT FROM AUTHOR]

According to the design scheme of natural resource balance sheet proposed by the author in previous study, this paper takes Zhuxi County, Shiyan City, Hubei Province as a case study and compiles the substance accounting table and value accounting table of Zhuxi County respectively by using statistic methods, market price law, alternative market law, willingness assessment law, etc., and the relationship between the changes of natural resources and regional economic development are analyzed. The results are as follows: 1) The total amount of forest and characteristic resources in Zhuxi County is increasing year by year. The industrial water consumption is decreasing year by year. The efficiency of industrial water is increasing continuously, while the resident living water keeps at a consant level. The water usage for urban public and ecological environment is increasing annually and the trend of agricultural water consumption remains constant. Water consumption is mainly affected by precipitation and other natural conditions. In the future, developing modern agriculture and improving agricultural water efficiency are necessary. In addition, land resources are in the trend of converting to construction land. The government of Zhuxi County should control construction area in a reasonable range. 2) The value of natural resources is in a relatively stable state which shows the natural resources are not over-consumed, and the value of land resources is the highest. The influence of human factors on the value of forest resources is positive and the total value is increasing. The influence of human factors on the value of water resources is negative. 3) With the increase of GDP in Zhuxi County, the total amount of natural resources has not reduced and remains relatively stable. The effect of human factors on the total value of natural resources is positive. [ABSTRACT FROM AUTHOR]