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1.
中国陆地生态系统生态资产遥感定量测量 总被引：58，自引：0，他引：58
生态系统的自然价值及其服务功能效益是地球生命支持系统的重要组成部分, 也是社会与环境可持续发展的基本要素. 生态资产是生态系统生物资源直接价值及其生态服务功能价值的总和. 对生态资产价值进行定量估算不仅可以从经济学的角度对生态环境进行定量评价, 而且能够引起全社会对生态环境建设的高度重视, 同时也是最终将其纳入社会与市场经济体系、建立绿色GDP核算体系、制定生态环境建设补偿政策的必要前提. 本文在传统生态学生态资产单位面积价值研究的基础上提出了基于遥感定量测量的生态资产价值评估模型, 并利用NOAA/AVHRR和其他辅助数据对模型所需要的参数, 如: 陆地生态系统地表覆盖类型、植被覆盖度(f)、植被第一性净生产力(NPP)进行了定量测量, 并参考Costanza等人的经济参数, 对中国陆地生态系统生态资产价值进行了全覆盖的定量测量, 并据此绘制了中国陆地生态系统生态资产价值空间分布图. 结果表明: 中国陆地生态系统每年的生态资产总价值为64441.77亿元人民币; 较之传统的生态学静态计算方法, 遥感测量克服了以点代面的缺点, 测量结果可以更加客观地反映中国陆地系统生态资产及其空间分布的现实情况, 为今后开展相关研究奠定了良好的基础. 相似文献
2.
当今在气候变化和人类活动等多重压力影响下,作为地表过程重要组成部分的湖泊生态系统正遭受着巨大威胁,其服务功能急剧退化.如何客观地评价湖泊生态系统服务的现状,并科学地预测其发展趋势,是当前亟待解决的问题.开展长期生态系统服务变化过程与机理的分析,有助于未来生态系统服务变化趋势的预测.然而,现有的观测数据往往时间较短(通常小于50年).连续的湖泊沉积记录为研究生态系统服务变化的长期过程提供了可能.本文结合前人研究成果,列举了可反映湖泊生态系统服务变化的一些古湖沼学指标,依据这些指标相对明确的生态和环境指示意义,将其与各项服务关联起来.最后,结合巢湖实例分析来说明这些指标在评估湖泊生态系统服务方面的具体应用,研究表明当今巢湖生态系统服务供应能力的持续增加是以调节服务的丧失为代价的.尽管目前的研究尚处于起步阶段,但古湖沼学手段无疑为今后湖泊生态系统服务历史状况的评估提供了途径,为古湖沼学的应用提供了一种新的思路,并为今后生态系统的保护和可持续利用提供重要的决策依据. 相似文献
3.
中国陆地生态系统服务净价值评估 总被引：1，自引：0，他引：1
生态环境保护是维护生态系统健康、改善生态系统服务功能、增加人类社会福祉的有效途径.然而,生态系统服务价值(VES)的获得必然会产生成本投入,传统的生态系统服务价值评估方法忽略了相关成本分析,给土地规划造成了混乱,不利于环境保护和社会经济的可持续发展.为了认知生态系统服务价值和净价值(NES)的差异,改进生态系统服务评价方法,该研究在生态系统服务价值研究的基础上,评估了1952年以来中国大陆主要生态系统(包括农田、草地、林地和湿地)服务净价值及其变化.结果表明,中国陆地生态系统年均服务净价值为10.0×10~3元/公顷,为服务价值的35.1%,草地生态系统服务净价值最低,为-0.7×10~3元/公顷;中国大陆农田、草地、林地和湿地2014年实现生态系统服务净价值7.2×10~(12)元,是全国国民净收益(居民可支配收入与政府收入的总和)25.6×10~(12)元的27.0%.1952年以来,由于人口增加的持续压力和环境政策的原因,中国陆地生态系统服务价值和净价值持续减少;1998年以后,中国政府陆续实施了一系列森林保护政策,中国陆地生态系统服务价值和净价值止跌回稳.但相关政策忽略了林地以外其他生态系统的保护,导致农田、湿地和草地等生态系统严重退化.由于社会经济条件、资源禀赋差异,不同地区之间的生态服务价值和净价值差异显著.为了维护生态平衡,生态修复(尤其是人工生态修复)和社会经济发展都应该注重成本效益问题,通过不同措施的成本收益比较,最大限度地降低生态保护项目的成本,增加环境保护项目的收益,这是修复生态学需要面对的重要科学问题. 相似文献
4.
湖泊生态系统服务（LES）在维持区域乃至全球生态安全格局中发挥重要作用，是目前生态系统服务研究的热点之一。由于湖泊面广量大、类型丰富、区域差异大及基础数据较为缺乏等原因，适用于LES定量评估且较为便捷、可行的模型方法较少。本文以博斯腾湖为例，基于生态系统最终服务与关键特征指标构建湖泊生态服务生产函数（LEPF），用于定量评估湖泊生态系统服务价值（LESV）并甄别关键特征指标的贡献度。结果表明：（1）博斯腾湖1990 2019年生态系统最终服务年均价值量为2226.84亿元，总体呈“上升下降上升”的变化趋势，气候调节、防洪蓄水为主导生态系统服务；（2）LEPF拟合结果较好地反映了5类关键特征指标对LESV的贡献度，从高到低依次为：湖泊水位>蒸发量>面积>水生植被面积>综合营养状态指数；（3）5类关键特征指标中水位的产出弹性较高，表明水位波动与生态系统最终服务价值变化密切相关。 相似文献
5.
水库生态安全评估方法(Ⅰ):IROW框架 总被引：6，自引：1，他引：5
近年来,生态安全评估在方法和实践上得到较大发展,然而,受水库特殊性、系统性认识缺乏等限制,目前尚无水库型水体的有效评估方法.本研究借鉴国外相关理念,分析了水库生态系统特征,强调了水库演变规律特殊性、水库时空异质性、水库生态系统管理综合性.着眼于此,提出了基于IROW(Inflow-Reservoir-Outflow-Watershed)框架的评估方法,将水库上游来水安全、水库水体安全、水库下泄水安全、库区流域影响4类要素纳入框架综合考虑;并阐述了评估预处理与结果分析的关注要点,包括分区、分时段评估等建议. 相似文献
6.
生态功能区划是我国正在开展的一项关于资源与环境管理的重大基础性工作.生态功能区划的理论和方法是当前生态学、环境科学、地理学等学科面临的一项新的热点课题.本文首先讨论了生态功能区划的概念,从认识区划看,生态功能区划属于生态系统区域划分的范畴,从实践的角度,则强调人文活动对生态系统可持续能力产生的影响,指出自然生态区不是生态功能区,生态功能区须反映人类的利用和价值判断.生态功能区划,不单是以自然要素或自然系统的"地带性分异"为基础,更是以生态系统的等级结构和尺度原则为基础,用生态系统完整性的评价测量人类活动对生态系统的影响,将生态功能区划的科学基础落在"基于生态系统的管理"平台上.文章提出了基于流域的我国生态功能区划的初步思想,讨论了区划的原则和方法,建立了生态系统完整性评价和功能区划分的指标体系.其基本内容是,认识并按照生态系统的自然边界划分生态系统单元;进行生态系统完整性评价;在此基础上划分不同的生态功能区,确定主导生态功能. 相似文献
7.
福建敖江流域水域生态系统健康评估 总被引：7，自引：1，他引：6
以敖江流域为研究区,通过采集底栖动物、鱼类等样品,结合监测数据分析流域水域生态系统健康状况,并采用指标体系评估方法对水域生态系统进行评估.结果表明:敖江流域水质总体良好,但山仔水库总氮、总磷浓度长期超标,水体存在富营养化和藻类水华暴发生态环境问题;底栖动物种类呈现支流多于干流、河流多于水库的规律;鱼类种类上、中、下游各科物种组成差异不显著,鱼类区系特点具有较明显的热带、亚热带区系特点;流域上游、中游水域生态健康良好,下游水域生态健康一般. 相似文献
8.
近30年来鄱阳湖生态系统服务变化 总被引：1，自引：0，他引：1
鄱阳湖是我国最大淡水湖,在维持区域生态安全和生态平衡中发挥重要作用.为了解近30年鄱阳湖生态系统服务变化情况,本文对已有文献与监测数据进行收集整理,直接获取鄱阳湖水资源供给、渔业资源供给、水环境净化服务数据,通过输沙量法、Berger-Parker优势度指数计算泥沙淤积调控和生物多样性维持服务,利用RMSD方法分析19922014年鄱阳湖生态系统服务关系.结果表明:(1)渔业资源供给和水环境净化服务不断下降,水资源供给和泥沙淤积调控服务在2010s有所恢复;(2)冬候鸟种类和数量增加,鱼类种群结构逐渐恢复,但Berger-Parker指数总体上升;(3)浮游植物、底栖动物多样性上升,浮游动物多样性下降;(4)不同时间尺度各服务间均为高权衡关系,水环境净化服务相对收益始终高于其他服务. 相似文献
9.
快速有效的生物监测指标对于评估、保护、管理和恢复淡水生态系统至关重要.传统评估方法主要利用指示生物或类群的出现率和多度信息,但是忽略了水体环境中“生物”与“生物”,以及“生物”与“环境”间相互作用的复杂关系,而这些相互作用对淡水生态系统的生物多样性、生态系统服务功能以及生态系统对环境变化的响应有着深刻影响.生物共现网络是群落水平物种互作的结构模型,通过物种在群落出现及丰度数据,描述了物种间潜在的相互作用、群落的基本结构,反映群落在生态系统的功能和结构特性.生物共现网络展示了淡水生态系统中所有生物体之间潜在的相互作用关系,其拓扑结构特性可与特定的生态系统状态相关联,能够揭示生态系统的组织规律及其功能,可作为早期的、灵敏的生物指标,是一种很有应用前景的评估淡水生态系统状态和稳定性的工具. 相似文献
10.
破坏性地震往往导致严重的经济损失及人员伤亡,对地震损失价值评价有助于震前找出抗震弱点,提高抗震能力,实现减轻地震灾害损失的目的。传统空间模型在地震数据处理过程中,无法处理大数据对空间尺度选择的干扰,存在地震损失评估结果偏差大以及波动性高的弊端。因此,在云计算平台下,提出基于大数据的地震损失价值评估模型设计,对模型HAZ-China大数据的服务层次、地震应用服务层以及HAZ-China大数据体系结构进行设计,为用户提供震前、震时以及震后的地震损失价值评估服务。模型采用HBase分布式数据库实现大数据的存储和分析,设计房屋震害数据库以及云计算模型,通过考虑大数据因素的地震灾害损失综合评估过程,实现地震损失价值的准确评估。实验结果说明,所设计模型可实现地震损失价值的准确评估,具有较高的评估精度和稳定性。 相似文献
11.
《水文科学杂志》2013,58(2)
Abstract Abstract The information regarding spatial and temporal variation of soil moisture in a catchment is of utmost importance in hydrological, as well as many other studies. Point measurements from gravimetric and other methods for soil moisture determination are insufficient to understand the spatial behaviour of soil moisture in a region. Microwave remote sensing data from active sensors on board various satellites are increasingly being used to map spatial distribution of soil moisture within the 0–10 cm top surface. The northern part of India has a network of large rivers and canals and, therefore, spatial and temporal distribution of soil moisture in this region has a significant bearing on the hydrology of the region. In this paper, results on estimation of soil moisture from an ERS-2 SAR image in the catchment of the Solani River (a tributary to the River Ganga) in and around the town of Roorkee, India, have been presented. The radar backscatter coefficient for each pixel of the image has been modelled from the digital numbers of the SAR image. Gravimetric measurements have been made simultaneously during the satellite pass to determine the concurrent value of volumetric soil moisture at a large number of sample points within the satellite sweep area. The backscatter coefficient is found to vary from –30 dB to –42 dB for a variation in soil moisture from 30 to 75%. Regression analyses between volumetric soil moisture and both the digital numbers and backscatter coefficients were performed. Strong correlations between volumetric soil moisture and digital number were observed with R 2 values of 0.84, 0.75 and 0.83 for bare soil, vegetative and combined surfaces, respectively. A similar trend was observed with the relationship between backscatter and volumetric soil moisture with R 2 values of 0.60, 0.89 and 0.67 for bare soil, vegetative and combined surfaces, respectively. These results demonstrate the utilization of SAR data for estimation of spatial distribution of soil moisture in the region of the present study. 相似文献
12.
T. S. Gubareva 《Water Resources》2011,38(7):962-971
The development of an optimal scheme for evaluation of maximal water discharges is discussed, including adequate probability
distribution laws, an effective procedure for their approximation based on observational data, and reliable goodness-of-fit
tests for analytical and empirical distributions. One-dimensional probability distribution laws are systematized. Promising
distributions were identified, including generalized distribution of extreme values, lognormal distribution, Pearson type
V power distribution, and GPD, for evaluating maximal discharges. The available methods for approximating analytical curves,
including the up-to-date method of L-moments are considered. Parameter estimation algorithm based on L-moment method for Pearson type III distribution is considered. Pearson type III distribution, lognormal distribution, GEV,
and GPD are compared in the approximation of maximal water discharges in rivers of Austria, Siberia, Far East, and the Hawaiian
Islands. 相似文献
13.
Different commonly used predictive equations for the reaeration rate coefficient (K2) have been evaluated using 231 data sets obtained from the literature and 576 data sets measured at different reaches of the River Kali in western Uttar Pradesh, India. The data sets include stream/channel velocity, bed slope, flow depth, cross‐sectional area and reaeration rate coefficient (K2), obtained from the literature and generated during the field survey of River Kali, and were used to test the applicability of the predictive equations. The K2 values computed from the predictive equations have been compared with the corresponding K2 values measured in streams/channels. The performance of the predictive equations has been evaluated using different error estimation, namely standard error (SE), normal mean error (NME), mean multiplicative error (MME) and coefficient of determination (r2). The results show that the reaeration rate equation developed by Parkhurst and Pomeroy yielded the best agreement, with the values of SE, NME, MME and r2 as 33·387, 4·62, 3·58 and 0·95, respectively, for literature data sets (case 1) and 37·567, 3·57, 2·6 and 0·95, respectively, for all the data sets (literature data sets and River Kali data sets) (case 2). Further, to minimize error estimates and improve correlation between measured and computed reaeration rate coefficients, supplementary predictive equations have been developed based on Froude number criteria and a least‐squares algorithm. The supplementary predictive equations have been verified using different error estimates and by comparing measured and computed reaeration rate coefficients for data sets not used in the development of the equations. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
14.
15.
Derivation and verification of empirical catchment response time equations for medium to large catchments in South Africa 
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下载免费PDF全文 Despite uncertainties and errors in measurement, observed peak discharges are the best estimate of the true peak discharge from a catchment. However, in ungauged catchments, the catchment response time is a fundamental input to all methods of estimating peak discharges; hence, errors in estimated catchment response time directly impact on estimated peak discharges. In South Africa, this is particularly the case in ungauged medium to large catchments where practitioners are limited to use empirical methods that were calibrated on small catchments not located in South Africa. The time to peak (TP), time of concentration (TC) and lag time (TL) are internationally the most frequently used catchment response time parameters and are normally estimated using either hydraulic or empirical methods. Almost 95% of all the time parameter estimation methods developed internationally are empirically based. This paper presents the derivation and verification of empirical TP equations in a pilot scale study using 74 catchments located in four climatologically different regions of South Africa, with catchment areas ranging from 20 km2 to 35 000 km2. The objective is to develop unique relationships between observed TP values and key climatological and geomorphological catchment predictor variables in order to estimate catchment TP values at ungauged catchments. The results show that the derived empirical TP equation(s) meet the requirement of consistency and ease of application. Independent verification tests confirmed the consistency, while the statistically significant independent predictor variables included in the regressions provide a good estimation of catchment response times and are also easy to determine by practitioners when required for future applications in ungauged catchments. It is recommended that the methodology used in this study should be expanded to other catchments to enable the development of a regional approach to improve estimation of time parameters on a national‐scale. However, such a national‐scale application would not only increase the confidence in using the suggested methodology and equation(s) in South Africa, but also highlights that a similar approach could be adopted internationally. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
16.
High spatial and temporal resolution of precipitation data is critical input for hydrological budget estimation and flash flood modelling. This study evaluated four methods [Bias Adjustment (BA), Simple Kriging with varying Local Means (SKlm), Kriging with External Drift (KED), and Regression Kriging (RK)] for their performances in incorporating gauge rainfall measurements into Next Generation Weather Radar (NEXRAD) multi‐sensor precipitation estimator (MPE; hourly and 4 × 4 km2). Measurements from a network of 50 gauges at the Upper Guadalupe River Basin, central Texas and MPE data for the year 2004 were used in the study. We used three evaluation coefficients percentage bias (PB), coefficient of determination (R2), and Nash–Sutcliffe efficiency (NSE) to examine the performance of the four methods for preserving regional‐ and local‐scale characteristics of observed precipitation data. The results show that the two Kriging‐based methods (SKlm and RK) are in general better than BA and KED and that the PB and NSE criteria are better than the R2 criterion in assessing the performance of the four methods. It is also worth noting that the performance of one method at regional scale may be different from its performance at local scale. Critical evaluation of the performance of different methods at local or regional scale should be conducted according to the different purposes. The results obtained in this study are expected to contribute to the development of more accurate spatial rainfall products for hydrologic budget and flash flood modelling. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
17.
Trend,periodicity and abrupt change in streamflow of the East River,the Pearl River basin 总被引：2，自引：0，他引：2 下载免费PDF全文
下载免费PDF全文 The East River in the Pearl River basin, China, plays a vital role in the water supply for mega‐cities within and in the vicinity of the Pearl River Delta. Knowledge of statistical variability of streamflow is therefore important for water resources management in the basin. This study analyzed streamflow from four hydrological stations on the East River for a period of 1951–2009, using ensemble empirical mode decomposition (EEMD), continuous wavelet transform (CWT) technique, scanning t and F tests. Results indicated increasing/decreasing streamflow in the East River basin before/after the 1980s. After the early 1970s, the high/low flow components were decreasing/increasing. CWT‐based analysis demonstrates a significant impact of water reservoirs on the periodicity of streamflow. Scanning t and F test indicates that significantly abrupt changes in streamflow are largely influenced by both water reservoirs construction and precipitation changes. Thus, changes of streamflow, which are reflected by variations of trend, periodicity and abrupt change, are due to both water reservoir construction and precipitation changes. Further, the changes of volume of streamflow in the East River are in good agreement with precipitation changes. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
18.
《水文科学杂志》2013,58(2):362-366
Abstract Most commonly used biochemical oxygen demand (BOD) and dissolved oxygen (DO) models have been tested for their applicability in the River Kali, which is one of the most polluted rivers in India. A total of 732 field data sets were generated during field survey from March 1999 to February 2000. The modelling of BOD and DO in the River Kali involves derivation and solution of the governing equations that describe concentration change with time and space brought on by advective, decay, settling and loading functions. However, due to continuous discharges (e.g. from wastewater treatment plants) and steady-state flow conditions in the River Kali, the dispersion effects are found to be insignificant. In the analysis, the model parameters used in BOD-DO models were optimized using the Newton-Raphson technique and the performance of different models was evaluated using correlation statistics (r 2) and error estimation, viz. standard error (SE) and mean multiplicative error (MME). The results indicate that the BOD-DO models developed after Camp (1963) yielded the best agreement with the observed values as compared with several other approaches. 相似文献
19.
Variability of phytoplankton biomass in a lowland river: Response to climate conditions 总被引：2，自引：0，他引：2
The results are presented of an intensive study of phytoplankton assemblage carried out in the Berounka River above its confluence with the Vltava River (Czech Republic) in the period 2002–2007. The annual and interannual changes of phytoplankton development (based on high frequency of sampling) and their relation to hydrological conditions and concentrations of main nutrients are analysed. A marked decline of nutrient concentrations was observed during the period 1996–2007. The annual mean values of total P decreased from 0.43 mg L−1 to 0.16 mg L−1, those of N-NO3 from 4.6 mg L−1 to 1.5 mg L−1 and N-NH4 from 1.9 mg L−1 to 0.04 mg L−1. Despite this, the phytoplankton biomass remained at a high level. The seasonal mean values of chlorophyll-a ranged from 51.0 μg L−1 to 116.8 μg L−1 in the same time period. An obviously stronger relationship was found of the phytoplankton biomass and pattern of its development to the variation of flow rates than to the existing level of nutrient concentrations. A significantly decreasing relationship (R2 = 0.384, P < 0.001) of chlorophyll-a to flow rates and a significantly increasing relationship (R2 = 0.359, P < 0.001) of chlorophyll-a to water temperatures were found, based on monthly mean values for the seasonal period 2002–2007. The results obtained indicate a remarkable increase of phytoplankton biomass and its prolongated occurrence in watercourses, which can be expected due to the consequences of the predicted climate change (i.e. higher occurrence of summer droughts and low precipitation amounts accompanied by a substantial drop of flow rates, increase of air and water temperatures), as described in the respective scenarios for the territory of the Czech Republic. Simulations by the regional climate models HIRHAM and RCAO and emission scenario SRES indicated the increase of air temperature by 2.5–5 °C, decrease of precipitation amount by 6–25% and decline of flows by 14–43% in the Berounka River for the scenario period 2071–2100. 相似文献
20.
In this paper, we quantify the terrestrial flux of freshwater runoff from East Greenland to the Greenland‐Iceland‐Norwegian (GIN) Seas for the periods 1999–2004 and 2071–2100. Our analysis includes separate calculations of runoff from the Greenland Ice Sheet (GrIS) and the land strip area between the GrIS and the ocean. This study is based on validation and calibration of SnowModel with in situ data from the only two long‐term permanent automatic meteorological and hydrometric monitoring catchments in East Greenland: the Mittivakkat Glacier catchment (65°N) in SE Greenland, and the Zackenberg Glacier catchment (74°N) in NE Greenland. SnowModel was then used to estimate runoff from all of East Greenland to the ocean. Modelled glacier recession in both catchments for the period 1999–2004 was in accordance with observations, and dominates the annual catchment runoff by 30–90%. Average runoff from Mittivakkat, ～3·7 × 10?2 km3 y?1, and Zackenberg, ～21·9 × 10?2 km3 y?1, was dominated by the percentage of catchment glacier cover. Modelled East Greenland freshwater input to the North Atlantic Ocean was ～440 km3 y?1 (1999–2004), dominated by contributions of ～40% from the land strip area and ～60% from the GrIS. East Greenland runoff contributes ～10% of the total annual freshwater export from the Arctic Ocean to the Greenland Sea. The future (2071–2100) climate impact assessment based on the Intergovernmental Panel on Climate Change (IPCC) A2 and B2 scenarios indicates an increase of mean annual East Greenland air temperature by 2·7 °C from today's values. For 2071–2100, the mean annual freshwater input to the North Atlantic Ocean is modelled to be ～650 km3 y?1: ～30% from the land strip area and ～70% from the GrIS. This is an increase of approximately ～50% from today's values. The freshwater runoff from the GrIS is more than double from today's values, based largely on increasing air temperature rather than from changes in net precipitation. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献