黄河流域城市生态环境需水量案例研究

根据城市生态环境需水量研究的需要 ,将黄河流域城市分为 5个类别 ,基于降水量和水资源量概念两个研究平台计算黄河流域城市生态环境需水量 ,并对其影响因子进行分析。结果表明 :1基于降水量概念的黄河流域城市最小生态环境需水量为7.95 5× 10 8m3,其中城市绿地和河湖最小需水量分别占总需水量的为 39.1%和 6 0 .9% ;基于水资源概念的黄河流域城市最小生态环境需水量为 6 .0 4 3× 10 8m3,占黄河流域城市市区供水总量的 12 .86 %。 2城市类别与城市生态环境需水量密切相关 ,随着城市级别的降低 ,基于降水量和水资源量概念的黄河城市最小生态环境需水量均呈现出逐渐减少的趋势。3黄河流域城市生态环境需水量表现出明显的空间差异性 ,黄河中下游地区形成城市生态环境需水量的高值区。4黄河流域城市生态环境现状用水量为 2 .876× 10 8m3,最小缺水量为 3.6 6 2× 10 8m3,其中城市绿地和河湖的最小缺水量分别为 0 .84 9× 10 8m3和 2 .830×10 8m3,亟需对黄河流域城市绿地和河湖系统进行补水。 5城市生态环境需水量与需水主体的状况密切相关 ,并受到城市面积、人口和 GDP等社会经济发展指标的深刻影响 ,而降水量、蒸发量和水资源量等自然条件对城市生态环境需水量的影响较小 ,体现出城市生态环境需水量人控     

基于管理目标的黄河三角洲湿地生态需水量

独特的地理位置和气候特征 ,使黄河三角洲湿地自然保护区孕育了丰富的自然资源和生物多样性。然而近些年来由于黄河上、中游开发不断 ,砍伐、引水工程等引发了下游特别是河口三角洲一系列的生态问题。表现在水资源紧缺、水体污染以及生物多样性减少等。根据黄河三角洲湿地自然保护区的现实问题以及 Ram sar公约要求 ,确定了黄河三角洲湿地自然保护区管理目标即保护新生湿地和鸟类资源 ,栖息地恢复与保护 ,生态系统功能与过程的维持等 3个层次的目标。通过分析湿地生物和水量的相关性 ,计算了不同层次管理目标的黄河三角洲湿地生态需水量 ,即在不考虑输沙用水的情况下 ,黄河三角洲湿地最小生态需水量、适宜需水量和理想需水量分别为 4 0 .95× 10 8m3、5 2 .4 5× 10 8m3和 6 7.93× 10 8m3;在考虑输沙用水的情况下 ,湿地最小生态需水量、适宜需水量和理想需水量分别为 190 .95× 10 8m3、2 0 2 .4 5× 10 8m3和 2 17.93× 10 8m3。     

基于生态保护目标的疏勒河中游绿洲生态环境需水研究

以疏勒河中游绿洲为研究对象,基于RS和GIS技术,选择1990年、2000年和2013年Landsat TM/ETM影像解译成果作为中游绿洲生态演变研究的基础资料,并确定了中游绿洲2020年和2030年生态保护目标。根据疏勒河中游绿洲生态环境需水特征,建立了基于天然植被、河流、湿地和防治耕地盐碱化的疏勒河中游绿洲生态环境需水定量化模型,并估算了现状和保护目标下流域中游绿洲生态需水量,从而为区域水资源合理配置和生态系统的协调发展提供参考依据。通过计算得出了疏勒河中游绿洲2013、2020和2030年天然植被、河流基本生态、河流输沙、河流渗漏补给、水面蒸发、湿地生态和防治耕地盐碱化生态环境需水量。同时得出疏勒河中游绿洲2013、2020和2030年疏勒河中游绿洲最大、最小和最适生态环境需水量分别为7.42×10~8、7.09×10~8、7.29×10~8,8.24×10~8、7.91×10~8、8.11×10~8m~3和9.12×10~8、8.79×10~8、8.99×10~8m~3。2013、2020和2030年疏勒河中游绿洲生态环境需水量年内变化主要集中于5—8月,累积生态环境需水量占全年的比例分别为58.01%、58.08%和58.13%;疏勒河中游绿洲生态环境需水量瓜州所占比例相对较大,玉门相对最小,敦煌介于二者之间。     

林地生态需水量计算方法与应用

从树木生长强度与土壤水分含量、蒸散量的相互关系出发 ,提出了林地生态需水量的等级标准和 计算方法 ,并以黄淮海地区为例 ,采用ＧＩＳ技术对该地区林地生态需水量进行了估算 ,分析了该地区林地在现状用水状况下的生态缺水量 .结果表明 ,该地区林地年生态需水量约 2 . 56× 1 0 1 0 ～ 4. 58× 1 0 1 0 ｍ3,在满足最小生态需水量要求下林地缺水量约为 2 .8× 1 0 9ｍ3,在满足适宜性生态需水要求下林地缺水量约为8.4× 1 0 9ｍ3.     

干旱内陆流域河道外生态需水量评价——以黑河流域为例

河道外生态系统需水量的合理评价是干旱区水资源合理配置与管理、生态环境保护与建设中最为关键的科学问题。基于不同植被蒸散发潜力估算模型,依据不同生态系统及同一生态系统在不同气候与地理区域具有不同生态需水规律的特点,提出了可模拟和评价不同时期生态系统需水量的方法,不仅能体现生态系统需水量的年际变化,也能反映年内不同时间段(月、季节甚至每日)的需水量变化,并提出干旱区生态适宜需水量在不同时期是一个区间。以黑河流域中下游地区为研究区域分析其生态需水量,结果表明:黑河中游地区年平均生态需水量(11.16±2.67)×108m3,其中绿洲生态系统需水(9.13±2.29)×108m3;下游地区生态需水量(16.16±4.04)×108m3,现状绿洲生态体系需水(11.06±2.77)×108m3,现阶段实施的下游分水9.7亿m3/年的方案,可以促使现有绿洲生态系统有一个良好的结构与功能,并给出了不同典型年不同月份的生态需水量及其变化。     

干旱区受水资源胁迫的下游绿洲动态变化趋势分析——以黑河流域额济纳绿洲为例

干旱内陆流域下游绿洲的形成与演变对流域地表径流变化响应强烈 .采用绿洲生态斑块动态模拟、植被与水盐状态相关分析、生态需水量估算等方法 ,分别对黑河流域下游额济纳绿洲在不同分水方案与水资源利用情景下的变化趋势进行了研究 .结果表明 ,维持现状绿洲面积不再萎缩 ,在考虑水资源利用合理化的前提下 ,其最低净需水量为 5 .7× 10 8m3 ,如果考虑下游地区人畜生活用水及工业用水 ,同时考虑水量在输送过程中的散失损耗 ,为在近期 (2 0 15年以前 )维持现状绿洲面积 ,狼心山断面入境流量需达到6 .0× 10 8m3 ;而要使绿洲面积恢复到 2 0世纪 80年代初的水平 ,狼心山断面过水量应不低于 8.9× 10 8m3 ,正义峡断面下泄水量要求达到 10 .9× 10 8～ 13.1× 10 8m3 .     

乌梁素海保护的生态需水量评估

结合乌梁素海湿地生态系统特征 ,基于保证水量、保证水质和改善水质 (对于污染湖泊 ) 3个层次的湖泊湿地保护目标 ,给出了不同环境保护目标下湖泊湿地的生态需水量估算方法 ,并在系统分析乌梁素海水文水循环特征的基础上 ,选择适合的计算方法 ,对乌梁素海不同保护目标下的生态需水量进行了估算。结果表明 ,从保证水量平衡角度看 ,乌梁素海排干系统排入湖泊水量为 6 .18× 10 8m3/ a,可以保证乌梁素海的水量平衡 ;从保证水质角度看 ,由于作为生态用水的黄河水总 N浓度超过国家地表水水质标准中湖泊水质 V类水标准限值的 1.6倍 ,比乌梁素海湖水总 N含量还要高 ,因此 ,完全达标的生态需水量是不存在的 ,但如果只考虑盐分和总 P,在现有排干水量为 6 .18× 10 8m3/ a条件下 ,则维持乌梁素海的盐分和 P浓度不变的生态需水量分别为 1.82× 10 8m3/ a和 12 .3× 10 8m3/ a;从保证湖水水质达标角度看 ,现有污染物排放情况下 ,1a盐分和总 P达标的生态需水量分别为 4 .91× 10 8m3/ a和 16 .3× 10 8m3/ a,10 a盐分和总 P达标的生态需水量应分别为 4 .2 8× 10 8m3/ a和 14 .3× 10 8m3/ a     

海河流域生态需水核算

从生态系统角度分析了生态需水内涵和生态需水与生态用水概念的差别。探讨了海河流域自然陆地、河流、湿地、城市 4种生态系统类型生态需水核算方法 ,并对其生态需水量进行了核算。大气降水首先被天然植被利用后形成地表径流 ,才能被人类管理利用来满足经济水量和生态水量需求。从水资源管理来说 ,河流、湿地、城市等生态需水来源于径流性水资源可称为狭义生态需水 ,而包括利用降水性水资源的天然植被生态需水在内的全部生态系统生态需水可认为是广义的生态需水。狭义生态需水是水资源管理及生态需水研究和关注的重心。研究结果表明 :海河流域河流生态需水 31.6 4× 10 8m3,占多年平均天然径流量的 12 % ;湿地生态需水为 34.31× 10 8m3,占 13% ;城市生态需水量 10 .83× 10 8m3,占 4 .1% ,3项合计占径流总量的 2 9.1%。生态需水量是一个动态的值 ,随生态保护目标的提高和经济的发展核算结果必然发生变化 ,维护生态环境质量的状况不同 ,也存在最大、最小生态需水量的阈值问题 ,此类问题需今后进一步研究     

洪河国家级自然保护区最小生态需水量与补水分析

湿地生态水文及其水资源优化配置已成为湿地研究中的重大科学问题之一.该研究基于湿地最小生态水位,以湿地静态补水与动态补水的定量方法,对洪河国家级自然保护区湿地最小生态需水量进行估算.研究结果表明:洪河湿地最小生态水位为51.5 m,静态需水量1863×104 m3,动态补水方案为1级补水量867.4×104 ～ 1518.0×104 m3/月,2级补水量693.9×104 ～ 1214.4×104 m3/月,3级补水量520.4×104 ～ 910.8×104 m3/月,4级补水量173.5×104 ～ 303.6×104 m3/月,5级补水量0.0×104 m3/月.研究确定的最小生态水位具有一定科学性,湿地生态水位提高30cm,能够为该区湿地植被群落的水生演替提供适宜生境.该研究结果可为其他湿地自然保护区的科学、有效管理提供理论依据.     

基于生态水位约束的下辽河平原地下水生态需水量估算

以我国北方典型的大型地下水盆地——下辽河平原为研究对象,在考虑地下水蒸发特点基础上,统筹考虑对地下水依赖程度较高的天然草地、天然湿地和河流生态系统对于地下水位的要求,综合水文和生态两方面因素确定地下水生态水位;利用Golden surfer软件的体积计算功能,计算出研究区内全年各月的地下水生态需水量;采用正态信息扩散模型,运用月保证率法得到不同保证率、不同恢复等级下的年地下水生态需水量.结果表明:下辽河平原不同月份的地下水缺水量41.83×108-60.07×108 m3、缺水区面积2.05× 104-2.34×104 km2、盈余水量2.73×108-6.68×108 m3、盈余区面积0.30×104-0.59×104 km2、地下水生态需水量35.15×108-57.33×108 m3;经月保证率法整合后的年地下水生态需水量变化规律为,随着保证率的降低,地下水生态需水量不断增加,而需水量等级越高,需水量增加幅度越大.     

Feedback loops between 3D vegetation structure and ecological functions of animals

Ecosystems function in a series of feedback loops that can change or maintain vegetation structure. Vegetation structure influences the ecological niche space available to animals, shaping many aspects of behaviour and reproduction. In turn, animals perform ecological functions that shape vegetation structure. However, most studies concerning three-dimensional vegetation structure and animal ecology consider only a single direction of this relationship. Here, we review these separate lines of research and integrate them into a unified concept that describes a feedback mechanism. We also show how remote sensing and animal tracking technologies are now available at the global scale to describe feedback loops and their consequences for ecosystem functioning. An improved understanding of how animals interact with vegetation structure in feedback loops is needed to conserve ecosystems that face major disruptions in response to climate and land-use change.     

塔里木河下游湿地面积时序变化及对生态输水的响应

及时了解和定量分析荒漠区河岸带湿地月度时序变化趋势及对生态输水过程的响应, 对认识湿地生态修复过程, 改进生态输水策略, 维护湿地生态系统稳定具有重要意义。该文基于Landsat ETM+/TM/OLI和Sentinel 2形成的月尺度的密集长时序遥感数据, 分析2000-2018年塔里木河下游英苏-阿拉干之间的湿地时序变化特征, 并评估湿地变化对生态输水过程的响应。结果表明: 近19年来湿地面积持续增加, 其中2011-2013年和2017-2018年是面积快速增加的时段。不同的单、双通道输水方式和输水量大小解释了喀尔达依湿地与博孜库勒湿地在不同时段增长的快慢。对湿地面积与生态输水量、地下水埋深关系的分析表明, 累计生态输水量的持续增加是近20年来塔里木河下游河岸带湿地扩张的重要因素, 每年大于3.5亿m ³的双通道生态输水, 地下水埋深维持在-5.0- -3.5 m是湿地持续稳定增长的关键。     

Ecological diatom guilds are useful but not sensitive enough as indicators of extremely changing water regimes

Classification of taxa into ecological guilds is based on the relation of respective taxa to nutrient enrichment and their resistance to physical disturbance. We hypothesized that ecological guild’s proportion and their taxa composition were strongly effected both by extremely changing water regime and nutrient contents. Diatom composition, guild dynamics and the diatom-based ecological status assessment index were studied in the Sebes-Körös River (South-East Hungary) in a year with extremely changing water regimes. There were highly pronounced changes in species composition during the whole vegetation period including the formation of running and standing water segments in autumn. While the proportions of ecological guilds showed no significant correlations with the studied environmental parameters, they were more balanced in high water discharge period than in the low water discharge period. Taxa compositions of segments were mainly determined by the preferences and strategies of a respective species and/or genera, regardless to their guild affiliation. These results point out that ecological guild characterisation should be refined using ecological knowledge at the subgenus level. We suggest to establish several subdivisions within the guilds to consider the differences in life strategies (CSR model) and life forms, and to implement the accumulated knowledge of nutrient preferences/indication of a respective taxa.     

Temporal areal changes of wetlands in the lower reaches of the Tarim River and their responses to ecological water conveyance

及时了解和定量分析荒漠区河岸带湿地月度时序变化趋势及对生态输水过程的响应, 对认识湿地生态修复过程, 改进生态输水策略, 维护湿地生态系统稳定具有重要意义。该文基于Landsat ETM+/TM/OLI和Sentinel 2形成的月尺度的密集长时序遥感数据, 分析2000-2018年塔里木河下游英苏-阿拉干之间的湿地时序变化特征, 并评估湿地变化对生态输水过程的响应。结果表明: 近19年来湿地面积持续增加, 其中2011-2013年和2017-2018年是面积快速增加的时段。不同的单、双通道输水方式和输水量大小解释了喀尔达依湿地与博孜库勒湿地在不同时段增长的快慢。对湿地面积与生态输水量、地下水埋深关系的分析表明, 累计生态输水量的持续增加是近20年来塔里木河下游河岸带湿地扩张的重要因素, 每年大于3.5亿m ³的双通道生态输水, 地下水埋深维持在-5.0- -3.5 m是湿地持续稳定增长的关键。     

Assessing human impact on fen biodiversity: effects of different management regimes on butterfly, grasshopper, and carabid beetle assemblages

Fens and concomitantly the associated species assemblages have undergone dramatic declines in recent decades. Given that many remaining or restored fens are currently lying fallow, an important question is which management regime, if any, is most effective in preserving fen biodiversity. Against this background we here investigate the effects of five management regimes (intensive grassland, moist meadows, summer harvested sites, winter harvested sites, fallows) on three insect taxa (butterflies, grasshoppers, carabid beetles) in riverine fens in north-eastern Germany. Butterflies and grasshoppers showed highest species numbers, diversity and numbers of threatened species on moist meadows and were detrimentally affected by high vegetation. In contrast, ground dwelling carabid beetles were less strongly affected by different management regimes, but responded very sensitive to drainage. Winter harvested sites and fallows seemed to be particularly beneficial to carabid beetles. Overall, drained, intensive grassland was not suitable for preserving fen-specific communities, while extensively managed moist meadows harboured overall the highest numbers of threatened species. We conclude that in terms of management maintaining high water tables is most important. Furthermore, some management seems necessary to maintain stands with lower vegetation turf for associated species. However, care is needed to also maintain fallows and to consider the specific demands of some highly endangered, management-sensitive species.     

The importance of water regimes operating at small spatial scales for the diversity and structure of wetland vegetation

1. In most cases, the most important determinant of wetland vegetation is the water regime. Although water regime is usually described and managed at the scale of whole wetlands, the patterning of vegetation is likely to be determined by water regimes that are experienced at much finer spatial scales. In this study, we assess the significance of internal heterogeneity in water regimes and the role that this heterogeneity plays in vegetation patterning. 2. The effects of water regime on wetland plant species richness and vegetation structure were studied at Dowd Morass, a 1500 ha, Ramsar‐listed wetland in south‐eastern Australia that is topographically heterogeneous. Data on plant variables and water depth were collected along 45 (50 m) transects throughout the wetland and related to water regimes assigned individually for each transect. Wetland plants were assigned to plant functional groups (PFG) that describe the response of plants to the presence or absence of water at different life stages. 3. The classification of water depth data indicated four distinct water regimes in the wetland that were differentiated primarily by the duration of the dry period. Representatives of all PFGs co‐existed over small spatial scales where topographical variation was present, and the richness and cover of understorey species declined as transects became more deeply and permanently flooded. Some PFGs (e.g. amphibious fluctuation tolerator‐low growing and amphibious fluctuation responder‐morphologically plastic) were eliminated by extended periods of flooding, which increased the cover but not richness of submerged plants. Species richness and foliage projective cover declined as water regimes shifted from shallow and frequently exposed conditions to regimes typified by deeper and longer inundation. Cover of the structurally dominant woody species was compromised by deeply flooded conditions but vegetative regeneration occurred despite high water levels. 4. Internal topographical variation generates mosaics of water regimes at fine spatial scales that allow plant species with different water regime requirements to co‐exist over small distances. Deep water and an absence of dry periods result in decreased cover of plants and an overall loss of species richness in the understorey. Water regimes are described that promote regeneration and cover of structurally dominant taxa and increased species richness in the understorey. The study demonstrates a strong association between vegetation and the diverse water regimes that exist within a single wetland, a pattern that will be useful for modelling the effects of modified water regimes on wetland vegetation.     

消涨带及三峡水库消涨带植被重建

重建三峡水库消涨带植被对于恢复消涨带功能、维持三峡工程安全和修复长江流域退化生态系统具有十分重要的意义。消涨带可分为自然消涨带和人工消涨带,自然消涨带及其植被是流域生态系统的组成部分,具有重要的生态、社会和经济价值。人为控制水位涨落而形成的人工消涨带很少有植被覆盖,属于退化的生态系统。三峡消涨带包括三峡自然消涨带和三峡水库消涨带,三峡工程的建设将淹没三峡自然消涨带及其植被并产生没有植被覆盖的三峡水库消涨带。作者认为开发利用三峡水库消涨带土地资源,发展库区经济将导致库区生态环境恶化、危及三峡工程安全且不利于长江流域生态系统的健康。解决三峡水库消涨带问题的关键是重建消涨带植被,并恢复其功能。该文从水利建设与环境保护的关系、三峡水库管理与库区景观建设的需要、消涨带功能恢复与流域生态系统康复和促进水库消涨带研究的深入阐述了开展三峡水库消涨带植被重建的必要性。     

Managed flooding can augment the benefits of natural flooding for native wetland vegetation

Managed flooding is increasingly being used to maintain and restore the ecological values of floodplain wetlands. However, evidence for its effectiveness is sometimes inconsistent and water available for environmental purposes often limited. We experimentally inundated a floodplain wetland (or “billabong”) in late spring by pumping water from its adjacent creek, aiming to promote the native wetland flora and suppress terrestrial exotics. Vegetation was surveyed before (spring) and after (late summer) the managed flood in the experimental billabong and in three control billabongs. Floodplain water levels were continuously monitored. Wet conditions caused two of the control billabongs to also flood, but to a lesser extent than the experimental billabong. We therefore assessed vegetation changes relative to flooding duration. With increasing flooding duration, the cover of wetland vegetation (amphibious and aquatic species) increased and the cover of terrestrial and exotic vegetation decreased, with these effects largest in the deliberately flooded billabong. Flooding durations greater than 20 days generally resulted in increased cover of wetland plants and restricted the growth of terrestrial plants. Reinstatement of more appropriate flooding regimes can thus promote native wetland plants, while suppressing terrestrial exotic species. Our study also provides evidence for the use of modest water allocations to augment the benefits of natural flooding in the maintenance and restoration of native wetland plant communities.     

The influence of agricultural system,stand structural complexity and landscape context on foraging birds in oil palm landscapes

Functional diversity, an important element of avian biodiversity, can be examined by quantifying foraging guild composition. Understanding the ecological processes that underpin functional diversity of birds in oil palm Elaeis guineensis landscapes is important because different foraging guilds are likely to be influenced in different ways by land use practices. We surveyed birds at 55 sites within oil palm landscapes and at 20 sites within logged peat swamp forest, recording 208 species belonging to 19 foraging guilds. Oil palm landscapes supported a lower abundance of insectivorous, granivorous and omnivorous birds than did logged peat swamp forest despite the latter being severely degraded due to intensive timber extraction. However, abundances of other groups of foraging birds, such as raptors and wetland taxa, were higher in oil palm landscapes than logged peat swamp forest. Frugivorous species were more abundant in smallholdings than plantation estates, probably because of the presence of native trees. Foraging guild diversity was explained by stand‐level attributes such as stand age, vegetation cover, epiphyte persistence and canopy cover. However, each foraging guild exhibited unique responses to different oil palm management regimes and stand‐level attributes. Only arboreal omnivores and terrestrial frugivores were affected by the proximity of nearby natural forest. This diversity of responses implies that the occurrence of particular avian foraging guilds may not be a suitable ecological indicator of best‐practice palm oil production. Our study also suggests that multiple conservation measures will be needed in oil palm landscapes irrespective of management regimes, including: (1) the maintenance of ground layer vegetation cover; (2) the pruning of oil palm canopy to permit light penetration to the ground layer; (3) re‐vegetation of parts of oil palm landscapes with native trees; and (4) retention of natural and/or secondary forest patches within the boundaries of plantations.