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

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

Analysis on the Area of Dongting Lake Before and After Building Three Gorges Dam Based on MODIS Image Sequences

[Objective] This study aimed to analyze the changes in the area of Donting Lake before and after building Three Gorges Dam based on MODIS image sequences. [Method] Based on the MODIS image sequences of 2000-2010, the change in the area of Dongting Lake in dry season and wet season before and after building Three Gorges Dam was analyzed, and the correlation between the change of the lake area in flood season and drought season and the record of Chenglingji Hydrological Observation Station was studied. [Result] The construction of Three Gorges Dam greatly influenced the area of Dongting Lake in dry season and wet season that in dry season, the linear relationship between the lake area and the waterline of Chenglingji was weak, while it was strong in wet season. [Conclusion] This study can estimate the changes of the area of Dongting Lake through the analysis on the waterline changes in Chenglingji, providing basis for the study on the changes in the area of Dongting Lake.

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

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

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

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

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

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

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

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

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

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

Embryonic Development of Silnrus asotus in Dongting Lake

[Objective] The research aimed to provide technical basis for fry rearing of Silnrus asotus in Dongting Lake.[Method] The induced spawning medicine was used in the experiment to conduct artificial induced spawning and fertilization for obtaining round green fertilized eggs.According to embryonic development,the morphological characteristics of embryo at different developmental stages were recorded detailedly through microscope.[Result] The embryonic development of Silnrus asotus in Dongting Lake was divided into 7 stages,namely, blastoderm stage,cleavage stage, blastula stage, gastrula stage,neurula stage,organogenesis stage and pre-hatching stage.After hatched for 37 h 20 min in water at 22-24 ℃, fries were come out.[Conclusion] The time sequence of Silnrus asotus in Dongting Lake was basically similar to that of other catfish,while its hatching time was shorter than that of other fish in Siluriformes.

Mathematical model for flood routing in Jingjiang River and Dongting Lake network

The main stream of the Yangtze River, Dongting Lake, and the river network in the Jingjiang reach of the Yangtze River constitute a complex water system. This paper develops a one-dimensional （l-D） mathematical model for flood routing in the river network Of the Jingjiang River and Dongting Lake using the explicit finite volume method. Based on observed data during the flood periods in 1996 and 1998, the model was calibrated and validated, and the results show that the model is effective and has high accuracy. In addition, the one-dimensional mathematical model for the river network and the horizontal two-dimensional （2-D） mathematical model for the Jingjiang flood diversion area were coupled to simulate the flood process in the Jingjiang River, Dongting Lake, and the Jingjiang flood diversion area. The calculated results of the coupled model are consistent with the practical processes. Meanwhile, the results show that the flood diversion has significant effects on the decrease of the peak water level at the Shashi and Chenjiawan hydrological stations near the flood diversion gates, and the effect is more obvious in the downstream than in the upstream.

FLOOD SIMULATION IN DONGTING LAKE DRAINAGE AREA AND ITS FLOOD CONTROL

On the basis of water-balance equation in Dongting Lake and Xiang Zi Yuan-Li River drainage areas, a possib1e flood height relating to the rainfall precipitation in these areas has been inferred. According to the flood simulation, some synthetic maintenance strategies to prevent future catastrophic f1oods in Dongting Lake drainage area have been also presented.

Architectural Design Concept of Dongting Lake Museum

Architectural design of Dongting Lake Museum takes "River dolphin ripples in the Dongting Lake" as the theme, tries to integrate into the local wetland environment and ecological resources of the Dongting Lake, in order to realize the dream of "making a great museum for the most gorgeous lake". The overall layout follows the concept of "coexistence of real and virtual, integration of exterior and interior", and the architectural image symbolizes "the river dolphin ripples", which is extremely harmonious in the whole natural environment. The design integrates planning, building, landscape and interior spaces, adopts technical means and ecological green to integrate the building into the environment, and presents us a tremendous ecological wetland museum that floats on the lake like a fish, an islet, a sail or a hill.

基于LMDI模型的土地利用碳排放时空差异及影响因素研究——以洞庭湖区为例

运用碳排放系数法和对数平均迪氏指数(LMDI)模型,对1996—2020年洞庭湖区土地利用变化、土地利用碳排放时空差异及其影响因素进行分析。结果表明:(1)土地利用变化整体呈现出“三增三减”特征,建设用地和未利用地的变化程度较为显著,水域和草地次之,耕地和林地的变化程度最小。(2)总净碳排放量呈不断上升趋势,碳排放高值区由中部转向西、东、南部,土地利用碳足迹压力指数始终大于1,以0.54的年均增幅不断上升。(3)人均GDP、单位GDP用地面积和单位土地碳排放强度是影响土地利用碳排放的主要因子,人均GDP和单位GDP用地面积分别成为促进和减缓洞庭湖区碳排放量增长的主要因素。

昆仑山北坡水资源科学考察初报

2021年10月首批启动了第三次新疆科学考察——“昆仑山北坡水资源开发潜力及利用途径科学考察”。结合多源遥感信息和2022—2023年野外科考工作,对昆仑山北坡的水文水资源变化和水资源利用进行了调查研究。结果表明:(1)1990—2020年,昆仑山北坡山区的气温、降水分别以0.14℃·(10a)^(-1)和6.53 mm·(10a)^(-1)幅度增加。(2)冰川变化相对稳定,积雪面积和积雪深度表现为略微增加。(3)永久性水体和季节性水体面积分别显著增加79.89%和144.49%。(4)东昆仑-库木库里盆地的阿牙克库木湖和阿其克库勒湖两大湖泊的水域面积分别增加了68.91%和58.22%,盆地内多条河流具备水资源开发潜力。(5)昆仑山北坡陆地水储量总体呈增加趋势,表现为从西向东增加趋势越加显著。(6)昆仑山北坡的主要河流和田河、克里雅河和车尔臣河年均径流量2010—2023年较1957—2023年分别增加了20.24%、27.85%和45.17%。(7)基于不同气候变化情景模拟预测至21世纪中后叶,主要河流径流量将保持上升态势,区域水资源量总体呈增加趋势。昆仑山北坡的水资源禀赋可为区域绿色高质量发展提供有利的水资源保障条件。

国土空间规划视域下国家公园适宜范围识别研究——以拟建洞庭湖国家公园为例

国家公园范围边界是平衡社会经济发展和生态保护的重要界线,作为国家公园设立的基础,范围识别是关系国家公园规划和建设管理能否顺利实施的先决条件,是其保护对象和管理目标的最直接体现。为科学识别国家公园范围,提出一套基于对生态系统原真性、生态系统完整性和管理可操作多重考虑的范围识别方法,并以拟建洞庭湖国家公园为例进行实证分析。研究结果表明:(1)选取生态系统原真性、生态系统完整性和可操作性三方面指标构建评价指标体系,进行叠加分析,识别国家公园范围,弥补了国家公园范围识别生态保护导向单一的不足。(2)研究区内生态系统原真性区域面积不大,仅1 165.46 km~2;维持了较好的生态系统完整性,完整性指数平均值为0.45;可操作性评价结果显示国家权属且属保护地所在空间的可行性指数较高。(3)洞庭湖国家公园适宜划定范围为2 145.7 km~2,包括了东洞庭湖、西洞庭湖和南洞庭湖三大片区,其中核心保护区205.8 km~2。可尝试动态评估自然生态系统原真性和完整性,并将国家公园纳入更大的保护地网络,为国家公园的创建和管护提供理论及实践借鉴。

Effects of the dispatch modes of the Three Gorges Reservoir on the water regimes in the Dongting Lake area in typical years

Based on the field-survey prototype hydrology data in typical years, the effect during the running periods of different dispatch modes of the Three Gorges Reservoir on the water regimes in Dongting Lake area is comparatively analyzed. The results are shown as follows. （1） The influence periods are from 25 May to 10 June, from 1 July to 31 August, from 15 September to 31 October and from December to the next April, among which the influence of the water-supplement dispatch in the dry season is not very sensitive. （2） During the period under the pre-discharge dispatch, the runoff volume slightly increases as well as both the average water level and the highest water level rise in the usual year. While in the wet and dry years, the average increase in the runoff volume is 40.25×1 08 m3 and the average rises of the average water level and the highest water level are both 1.06 m. （3） As for the flood-storage dispatch, the flood volume increases slightly, in the dry and wet years, the flood volume, the average water level and the highest water level averagely reduce by 444.02×108 m3, 2.64 m and 1.42 m respectively. （4） Under the water-storage dispatch, the runoff volume slightly in- creases and the water level heightens in a sort in the usual year. And in the dry and wet years the average decreases in the runoff volume, the average water leve/and the highest water levels are respectively 185.27×108 m3, 3.13 m and 2.14 m. （5） During the period under the water-supplement dispatch, the runoff volume, the average water level and the highest water levels averagely decline by 337.7×108 m3, 1.89 m and 2.39 m respectively in the usual and wet years. However, in the dry year, the runoff volume increases as well as the average and highest water levels slightly go up.

基于数字足迹的洞庭湖区游客感知研究

洞庭湖区是湖南省旅游战略发展要地,探究该区游客感知有利于提升目的地旅游形象.以洞庭湖区数字足迹为原始数据,运用文本分析法探究游客对洞庭湖区旅游的整体感知.研究发现,洞庭湖区旅游目的地整体形象较好;洞庭湖区游客多集中于岳阳市,常德市、益阳市等游客到访量较少.游客对洞庭湖区旅游发展的感知以积极情绪为主,整体满意度较高,也有游客认为旅游发展没有达到预期效果,体验感差.基于上述研究结果,提出丰富旅游产品业态、优化目的地旅游环境、深度开发旅游产品等建议,以期为洞庭湖区旅游发展提供新思路.

洞庭湖区旅游产业与生态环境适应性时空演变及影响因素

【目的】诊断旅游产业与生态环境适应性,为旅游产业高质量发展和生态环境可持续承载提供参考依据。【方法】从旅游产业和生态环境2个子系统,压力、状态和响应3个维度构建旅游产业与生态环境适应性评价指标体系,运用熵权Topsis法、适应性评价模型、标准差椭圆及地理探测器,分析洞庭湖区2012—2021年旅游产业与生态环境适应性时空演变及影响因素。【结果】1)旅游产业指数呈现升—降—升变化趋势,生态环境指数呈现波动上升趋势,旅游产业与生态环境适应性指数时空差异显著,呈现中部地区较低、四周地区较高的“盆地型”空间分布格局。2)近10年来适应性时空迁移趋势以东西方向为主导,空间离散程度呈现出先扩大后缩小的变化趋势,重心位于洞庭湖中部地区,集聚特征明显。3)旅游产业与生态环境适应性类型以低度适应为主,县域占比达41.18%,空间格局表现边缘地区>外围地区>中部地区的分布特征。4)旅游资源禀赋、政府调控力度、经济发展水平和环境治理能力是驱动旅游产业与生态环境适应性时空演变的重要因素。【结论】洞庭湖区旅游产业与生态环境适应性较低,县域发展不平衡、不充分问题较突出。未来洞庭湖区旅游产业发展,应立足生态环境承载能力,科学开发旅游资源,加强区域旅游合作,提高旅游产业与生态环境的适应能力。

洞庭湖地区生境水生态空间结构和功能的时空分异

【目的】为延缓洞庭湖地区生境质量持续下降和生态服务功能继续减弱,从结构、功能和质量的角度提出生境水生态空间可持续发展研究框架,以期为生态空间保护和水安全保障提供理论依据。【方法】基于土地利用和社会统计数据,借助ArcGIS分析手段,对洞庭湖地区2010、2015和2020年3个年份的生境水生态空间的结构、功能及质量状况进行监测,并提出管控框架和关键举措。【结果】1)洞庭湖地区生境水生态空间总体规模在7300 km^(2)以上,其中水体区域所占比例最大,其次是临岸陆生区,而水陆交错区所占比重最小,研究期间生境水生态空间面积存在小幅减少;岳阳市的生境水生态空间总体规模较大,临澧县的生境水生态空间规模较小。2)洞庭湖地区生境水生态空间的综合功能约为0.4000,研究期间有一定提升;各单元中,沅江市生境水生态空间综合功能价值最高,津市市生境水生态空间综合功能价值则相对最低。3)生境质量在空间分布上呈现出明显的空间分异,以洞庭湖及沿岸河流、东部与南部山地丘陵区为高生境质量集中分布区,而在地形平坦、人口经济活动较密集的城镇地区的生境质量较低。【结论】应从生境水生态空间的结构要素出发,科学规划生境水生态空间功能分区,并与“三区三线”划定相结合,在此基础上推动多尺度多层级生境水生态空间可持续发展关键举措的实施。

基于“人与自然生命共同体”理念的国土空间生态修复策略——以洞庭湖区为例

“人与自然生命共同体”理念是对“山水林田湖草沙生命共同体”理念的丰富和发展,其本质是以人为主体的自然-社会复合生态系统,或国土空间生态系统。为研究该理念对国土空间生态修复的作用和意义,在阐释该理念内涵的基础上,提出国土空间多层次系统生态修复模式,并以洞庭湖区为例,从要素、系统、管理、文化4个层层递进,既相对独立,又相互联系的层面制定生态修复策略和措施。

“大利在淤”:清末沅江县湖田升租与升科之争

自清初至光绪前期,清政府对淤洲的征税都是开垦数年之后升科,百姓可以享有湖田业权。受地势影响,滨湖洲地的收益悬殊,清政府在征税时体恤民情,对地势低下者加以豁免。雍正元年起,清政府便确立了“水田六年起科,旱田十年起科”的定例。乾隆初年,清政府对所有二亩以下“零星土地”正式免除升科。针对地势低洼的濒江洲地和洲田,清政府仅征收芦课,具体额度因地制宜,五年一丈。但自光绪十六年(1890)湖南巡抚王文韶奏请将洞庭湖区淤洲统一收为官荒后,官方便开始采取强势介入的态势。不过,湖区原有的产权秩序仍然在发挥作用,省府在华容等开发较早的地区也只得承认部分湖田的民业性质。至光绪二十九年(1903),湖南省的财政状况明显恶化,筹备总局试图按照南洲章程对沅江县成熟垸田进行升租。然而,沅江知县张谟等在勘察报告后表示异议,原因是沅江县对湖田一向是纳税升科,未有升租成案。垸董们也多次呈文反对升租并提议升科,这不仅是因为升租要缴纳的钱数更多,还在于他们投入大量资本筑堤建垸却无法获得湖田的合法业权。然而,省府仍然打破原有定例,坚持对民垸熟田进行升租,目的是将租课归地方开支而无需上缴中央。不过,这一过程在争论落幕六年后才得以完成,在垸董接受升租办法的同时,省府也不得不承认“由民筑围成垦者”是“民垸”而非“官田”,且在折亩时给予优惠。湖田本身变动无常的自然特性、清政府治理能力的局限、地方绅董的崛起等因素使省府和垸董之间不得不相互妥协,达成一种微妙但脆弱的平衡。