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1.
The protection, restoration and sustainable use are key issues of all the wetlands worldwide. Ecological, agronomic, and engineering techniques have been integrated in the development of a structurally sound, ecologically beneficial engineering restoration method for restoring and utilizing a degraded saline wetland in the western Songnen Plain of China. Hydrological restoration was performed by developing a system of biannual irrigation and drainage using civil engineering measures to bring wetlands into contact with river water and improve the irrigation and drainage system in the wetlands. Agronomic measures such as plowing the reed fields, reed rhizome transplantation, and fertilization were used to restore the reed vegetation. Biological measures, including the release of crab and fish fry and natural proliferation, were used to restore the aquatic communities. The results of the restoration were clear and positive. By the year 2009, the reed yield had increased by 20.9 times. Remarkable ecological benefits occurred simultaneously. Vegetation primary-production capacity increased, local climate regulation and water purification enhanced, and biodiversity increased. This demonstration of engineering techniques illustrates the basic route for the restoration of degraded wetlands, that the biodiversity should be reconstructed by the comprehensive application of engineering, biological, and agronomic measures based on habitat restoration under the guidance of process-oriented strategies. The complex ecological system including reeds, fish and crabs is based on the biological principles of coexistence and material recycling and provides a reasonable ecological engineering model suitable for the sustainable utilization of degraded saline reed wetlands.  相似文献   

2.
三江源是中国陆地生态系统最脆弱和敏感的区域之一,一旦遭到破坏则不可逆转。受三江源地区多云等不利气象条件的影响,很难获取大范围尺度上季相一致的、无云的Landsat遥感影像。本文利用Google Earth Engine平台,对1990-2015年的相同季节的3766景Landsat影像进行像元级融合并重构最小云量影像集,借助GEE的并行云端计算,快速得到了能够反映生态环境质量的遥感生态指数(RSEI),对三江源地区的生态环境质量进行了评价与监测。三江源时空变化与差异分析表明:1990-2000年生态环境质量呈快速下降状态,RSEI平均值从0.588下降到了0.505,生态环境质量变化以轻度恶化为主;2000-2015年生态环境质量下降速度变缓,并于2015年呈现变好态势,生态环境质量变化以不变为主,且轻度恶化面积大幅减少;该地区的生态环境状况呈现出空间分异,自西向东,生态状况变差。基于GEE平台在三江源地区的实验结果表明,GEE可以作为大区域范围的生态环境质量评价与监测的计算平台。  相似文献   

3.
近年来,随着观测数据的增加、观测精度的提升、物理化学理论的不断完善以及计算机技术的显著提升,使得人们对岩石圈物理化学性质的认识发生了重大改变。介绍了目前关于岩石圈结构成像的相关方法以及它们的优缺点,并以华南地区4个具有代表性的区域(四川盆地、江南造山带、下扬子克拉通以及华夏块体)为例,利用地形、大地水准面、地表热流、地震面波频散曲线等观测资料,通过热动力学模拟和概率密度反演方法,给出了该地区岩石圈温度、化学组分结构。结果显示,华南块体东部岩石圈较薄,岩石圈地幔以饱满型橄榄岩为主,太平洋板块由东往西的平俯冲作用可能是华南东部岩石圈减薄的主要动力学机制。结合现今岩石圈结构的研究现状,提出了岩石圈结构成像存在的问题,并对未来岩石圈结构成像研究进行了展望。   相似文献   

4.
经过几十年的历程,江苏物探技术的应用领域在不断拓宽.回顾了几十年来江苏物探工作发展的4个阶段.提出了在新的世纪中人口、资源、环境将是最为突出的三大热点问题.江苏物探工作任重道远,尤其在矿产资源勘查和环境检测与防治方面,将成为江苏物探技术大显身手的领域.  相似文献   

5.
露天矿区土地复垦及生态重建数据库的设计与实现   总被引:1,自引:0,他引:1  
矿区土地复垦与生态重建研究以及复垦模式的验证、推广,都需要借助数据库技术对多年研究数据进行有效的组织管理。本文论述了土地复垦与生态重建数据库设计过程中的用户需求分析、概念结构设计、逻辑结构设计、物理结构设计以及数据库的实施与维护。该研究促进了矿区土地复垦与生态重建工作的信息化。  相似文献   

6.
稀土是世界各国的战略性关键金属矿产资源,而中重稀土尤为重要。老挝境内分布着大量不同时代花岗岩类,且气候湿热多雨,风化作用强烈,为离子吸附型稀土矿的形成创造了有利条件。为查明老挝稀土资源成矿地质特征和资源分布特征,分析其投资开发前景,对整个老挝境内开展了大量系统的野外调研及相关分析测试工作,并且汇总了老挝稀土资源勘查工作进展。研究结果表明,老挝稀土资源成矿特征可类比中国南方地区,属于典型的风化壳淋积型矿床,矿体主要富集于花岗岩类风化壳全风化层,盖层厚度相对中国较大。矿体呈层状、似层状和透镜体状,厚度数米到二十多米。离子相稀土平均品位为0.4‰~0.7‰,大部分稀土配分模式同江西赣州信丰稀土矿相似,属富集中重稀土元素的中钇富铕型。老挝稀土资源主要分布于北部的川圹省和华潘省,预计两省稀土资源总量可达到60万t。随着老挝稀土政策的开放和中国稀土战略的逐步完善,投资开发老挝稀土资源,建立稀土资源的海外战略基地,可以长期稳定地支撑中国对离子吸附型稀土资源的需求,同时也可以为加强两国合作、共建中老命运共同体做出突出贡献。   相似文献   

7.
无人机是获取地表数字图像和进行样品采集的重要手段,近年来在沉积学领域正逐渐成为一种新兴的研究手段,改变着沉积学的研究范式。然而,目前国内基于无人机的沉积学研究尚处在起步阶段,本研究拟回顾近年来无人机在沉积学领域研究中的重要应用,对所涉及的关键技术背景和存在的问题进行了讨论,总结并展望了未来的发展前景,以期对后续相关研究提供参考。主要从沉积露头的三维数字重建、高分辨率沉积结构和构造特征的提取以及无人机协助样品采集3个方面综述了无人机在沉积学应用中的软硬件要求及典型研究案例。利用无人机摄影测量技术构建数字露头模型,有利于从多个空间尺度和视角观察沉积露头的几何形态、沉积相与岩相组合情况,结合数字露头模型信息提取软件,可对粒度、交错层理和生物遗迹等沉积结构和构造特征进行大范围的远程而高效的提取,未来还可进一步应用于沉积学野外实践教学工作中。此外,对无人机本身进行改造,还能够协助进行冰心等沉积物样品的采集。应用无人机技术进行沉积学研究,具有低成本和高效率的优势,保证了数据的时效性和连续性,也提高了野外工作的安全性。但是,无人机技术在数据可重复性、点云处理以及图像与模型质量方面也存在着不足。未来可借助人工智能方法,以及通过制定无人机图像采集与处理流程的标准规范来进一步改善。   相似文献   

8.
江苏省矿产品进出口贸易对我省国民经济的发展起着十分重要的作用.分析了江苏省矿产品进出口贸易现状、供需形势、加入世界贸易组织的影响,提出了我省能源、钢铁等矿产品存在资源紧缺、供需矛盾较突出的严峻问题,为政府对矿产品进出口政策作出调整提供依据.  相似文献   

9.
近30年来青海省三江源区草地的土壤侵蚀时空分析   总被引:5,自引:0,他引:5  
分析了青海省三江源区草地生态系统土壤侵蚀的空间差异,以及草地退化与土壤侵蚀的关系,并对该区近30年来土壤侵蚀的动念变化进行描述.结果表明,该区域微度以上土壤侵蚀面积占源区总面积的46.47%,而草地生态系统发生微度以上土壤侵蚀的面积比例达56.04%.源区土壤侵蚀类型是以冻融侵蚀伴随着水力侵蚀或风力侵蚀的复合侵蚀为主,...  相似文献   

10.
当前我国生态修复资金投入总体不足,且以政府投入为主。政府投入模式面临财政赤字和政府债务负担约束。为了减轻政府财政压力,充分发挥社会资本在生态修复工作中的作用,有必要建立社会资本参与生态修复的长效机制。本文选取发达国家吸引社会资本投入与生态修复的典型案例,从社会资本投入生态修复的驱动力和收益途径角度,分析其主要做法和经验,从强化法律约束、完善产权制度、加大投融资政策供给等角度提出完善社会资本投入生态修复机制的建议。  相似文献   

11.
Over the last several decades, the Mediterranean region has been subjected to mountain abandonment and farming cessation, leading to changes in vegetation and coenological features of grasslands, contextually to the strong decline of the rock partridge(Alectoris graeca). Our hypothesis was that the ongoing dynamic processes leading to the compositional changes of grasslands in central Apennines affect the habitat suitability for the singing male(territorial male defending its reproductive site).In 2015, we defined the presence/absence of spring territorial singing males in seven sites(1,250-2,400 m a.s.l.), by the census in 74 playback stations,distributed along 15 transects. We characterized the topography and the vegetation mosaic of such sites according to the collected topographic and vegetation cover data in 59 randomly selected plots(100 m × 100 m) along the transects. To understand the relations among the environmental variables and the effect of the composition and dynamism of the vegetation mosaics on the presence/absence of the singing male,we used principal components analysis and generalized linear mixed-effect modelling. Our results emphasized the marked overlap between the general environmental conditions, which proved to define the habitat suitability for A. graeca, and the characteristics of the site chosen by the singing male for starting the reproductive activities. Moreover, we found that the site suitability for the singing male decreases when the vegetation recovery processes are ongoing, because of the spread of coarse tall grassesdominated communities and/or grassland types with dense turf. Tall grass-dominated communities and thick-turf grasslands exert their negative effect decreasing the habitat suitability for the singing male starting from low cover values. Therefore, it is conceivable that singing male's suitable habitat will be dramatically restricted to the steepest south-facing slopes, where topographic and soil conditions do not allow the spread of grasslands with dense turf and of invasive/dominant tall grasses, increasing the threat to the species due to the effect of climate change on the vegetation features.  相似文献   

12.
Accurate estimate of soil carbon storage is essential to reveal the role of soil in global carbon cycle. However, there is large uncertainty on the estimation of soil organic carbon (SOC) storage in grassland among previous studies, and the study on soil inorganic carbon (SIC) is still lack. We surveyed 153 sites during plant peak growing season and estimated SOC and SIC for temperate desert, temperate steppe, alpine steppe, steppe meadow, alpine meadow and swamp, which covered main grassland in the Qinghai Plateau during 2011 to 2012. The results showed that the vertical and spatial distributions of SOC and SIC varied by grassland types. The SOC amount mainly decreased from southeast to northwest, whereas the SIC amount increased from southeast to northwest. The magnitude of SOC amount in the top 50 cm across grassland types ranked by: swamp > alpine meadow > steppe meadow > temperate steppe > alpine steppe > temperate desert, while the SIC amount showed an opposite order. There was a great deal of variation in proportion of SOC and SIC among different grassland types (from 55.17 to 94.59 for SOC and 5.14 to 44.83 for SIC). The total SOC and SIC storage was 5.78 Pg and 1.37 Pg, respectively, in the top 50 cm of soil in Qinghai Province. The mixed linear model revealed that grassland types was the predominant factor in spatial variations of SOC amount while grassland types and soil pH accounted for those of SIC amount. Our results suggested that the community shift of alpine meadow towards alpine grassland induced by climate warming would decrease carbon sequestration capacity by 6.0 kg C m2.  相似文献   

13.
枣庄市山体资源丰富,矿产资源开发利用程度较高.资源开发利用在很长时期内促进了枣庄市经济的快速发展,但也遗留了很多地质环境问题.本文总结了枣庄市破损山体调查工作技术方法,根据调查成果和现行的枣庄市矿山地质环境保护和治理规划,系统分析了全市破损山体的分布特征及存在的地质环境问题.综合参考全市"生态红线"划定成果、破损山体与...  相似文献   

14.
三北地区是我国重要的生态屏障,分析2000—2019年三北防护林体系建设工程(简称:三北工程)区植被恢复时空变化状况,厘定人类活动与气候要素对植被恢复的贡献,探究植被恢复对土壤风蚀影响,评估植被恢复潜力空间,可为三北防护林体系建设工程未来规划管理和科学施策提供参考。本文在选取植被覆盖度和植被净初级生产力表征植被恢复状况基础上,利用地面数据,结合模型模拟,定量评估了2000—2019年三北防护林体系建设工程区植被恢复程度及其对土壤风蚀的影响,并对植被恢复潜力进行探究。研究结果表明:(1) 2000—2019年植被恢复程度高、较高的面积,占总面积的35.29%和13.16%,主要分布在黄土高原区及北部区域和风沙区与东北华北平原农区的部分地区。人类活动与气候因素对植被恢复贡献率为10.45%和89.55%;(2)土壤风蚀以轻度侵蚀和微度侵蚀为主,呈逐年下降趋势,剧烈侵蚀面积减少了66.45%,防风固沙服务得到进一步提升。植被恢复程度与土壤风蚀模数呈负相关关系,植被恢复程度较好有助于降低土壤风蚀模数;(3)三北工程区森林、草地和荒漠生态系统仍有8.16%的恢复潜力,内蒙古高原北部部分地区、哈顺...  相似文献   

15.
Wetland economic valuation approaches and prospects in China   总被引:1,自引:0,他引:1  
Ecosystem services valuation seeks to increase the social relevance of ecosystem characteristics, the underlying biological mechanisms that support services, by making the contribution of ecosystems to human well-being explicit. Economic valuation can help management by clarifying the full range of benefits and costs of proposed management actions. In the past two decades, economic valuation of wetland ecosystem services has become one of the most significant scientific priorities for wetland protection. In this paper, we provide an overview of ecosystem services, and summarize the main interdisciplinary approaches to measure and value wetland ecosystem services. We identified four main methodological gaps preventing progress on wetland valuation of ecosystem services in China, which are: 1) confusion on terminology like intermediate and final ecosystem services, 2) lack of ecological production functions to link ecosystem characteristics to final ecosystem services, 3) static valuation making it difficult to evaluate the trade-offs and synergies among ecosystem services, and 4) lack of clear guidance on relating ecological compensation programs to conservation targets. Overcoming these gaps is important to inform wetland compensation mechanisms and conservation policies. We propose future research on wetland ecosystem services in China should be focused on: 1) defining final ecosystem services based on beneficiary preferences and underlying biophysical mechanisms, 2) establishing wetland monitoring programs at specific sites to collect data on final ecosystem service indicators and ecosystem characteristic metrics to create ecological production functions for economic valuation and rescaling techniques, and 3) incorporating wetland ecosystem service values into decision-making processes to inform wetland management.  相似文献   

16.
Species diversity exhibit a close relationship with ecosystem services, and making clear the relationship can help us understand the service value and functional mechanism of ecosystems and take measures to promote human well-being. Here, we used species survey data and multi-source habitat factors to simulate the spatial distribution of species richness and four types of ecosystem services(water production, net primary productivity, carbon storage, and habitat quality) in Sanjiangyuan National Park located in Qinghai Province, China. We also analyzed the spatial distribution pattern and explored the spatial relationship between species richness and ecosystem services through Geo Detector analyses. We found that high species richness in Sanjiangyuan National Park was shown to be mainly distributed in areas with high vegetation growth on both sides of rivers. The effect of climate on the spatial distribution of species richness in the park is the highest among all the selected environmental variables. For the relationship between species diversity and ecosystem services, the relative correlation strength of single ecosystem service varied among the three main ecosystems(grassland, meadow, and wetland) and all relations are positive.  相似文献   

17.
In this study, two adjacent gauged catchments on the Chinese Loess Plateau were selected, in which one catchment was afforested and one was restored with natural vegetation in 1954. The distributions of soil erosion rates were estimated between 2010 and 2020 with a high spatial resolution of 2 m in the paired catchments based on the Revised Universal Soil Loss Equation model(RUSLE) and Geographic Information Systems(GIS). The results showed that the simulated soil erosion rates in 2010-2020 aver...  相似文献   

18.
Grassland fire is one of the most important disturbance factors in the natural ecosystems.This paper focuses on the spatial distribution of long-term grassland fire patterns in the Hulun Buir Grassland located in the northeast of Inner Mongolia Autonomous Region in China.The density or ratio of ignition can reflect the relationship between grassland fire and different ignition factors.Based on the relationship between the density or ratio of ignition in different range of each ignition factor and grassland fire events,an ignition probability model was developed by using binary logistic regression function and its overall accuracy averaged up to 81.7%.Meanwhile it was found that daily relative humidity,daily temperature,elevation,vegetation type,distance to county-level road,distance to town are more important determinants of spatial distribution of fire ignitions.Using Monte Carlo method,we developed a time-dependent stochastic ignition probability model based on the distribution of inter-annual daily relative humidity and daily temperature.Through this model,it is possible to estimate the spatial patterns of ignition probability for grassland fire,which will be helpful to the quantitative evaluation of grassland fire risk and its management in the future.  相似文献   

19.
The present paper gives an insight into the distribution and use pattern of medicinal shrubs in Uttaranchal State. A total of 222 medicinal and aromatic shrub species have been appended based on secondary information. Euphorbiaceae, Rosaceae, Verbenaceae, and Fabaceae have the highest repre- sentatives of medicinal shrubs. Twenty one families had one species each in medicinal use. Verbenaceae and Euphorbiaceae in the sub-tropical region, Rosaceae in the temperate region, and Ericaceae and Rosaceae in the sub-alpine and alpine regions, respectively, had the highest representatives of medicinal shrubs. The distribution of medicinal shrubs was 42 % in sub-tropical, 29 % in warm temperate, 13 % in cool temperate, 9 % in sub-alpine and 7 % in the alpine region. Of the total species, 70 medicinal shrubs were native to the Himalayas and 22 native to Himalayan region including other Hima- layan countries. The most frequently used plant parts for various ailments were leaves (31 %) and roots (23 %). Most shrubs are being used for the diseases, viz. skin diseases, dysentery, cough, fever, wounds, and rheumatism. The present paper will help in the execution of strategies for promotion and cultivation of medicinal shrubs in Uttaranchal State.  相似文献   

20.
A thorough understanding of the vegetation succession in relation to both climatic changes and anthropogenic activities is vital for the formulation of adaptation strategies that address potential ecosystem challenges. Various climatic factors such as temperature, precipitation, and solar radiation, as well as anthropogenic factors such as ecological engineering and population migration, will affect the conditions for vegetation. However, the relationships among various factors remain unclear and the response of vegetation to climate change and anthropogenic activities in the Loess Plateau of China has not been well established. This study investigated the spatio-temporal characteristics and relationships between vegetation coverage and climatic factors in the Loess Plateau for the period of 1985–2015. Further analysis separated the anthropogenic and climatic factors on vegetation succession based on residual analysis. The results showed that the normalized difference vegetation index(NDVI) followed a significant upward trend with annual change rates of 0.15% during 1985–2015. The trend of human-induced NDVI increase was consistent with the spatial distribution of increasing forest areas in the eastern part of the Loess Plateau. Eco-restoration projects were the main driving factors that promoted vegetation coverage on the Loess Plateau. Furthermore, these results demonstrated that migrants to cities in the Loess Plateau could relieve ecological pressures and promote vegetation restoration. Therefore, the government should strive to increase population mobility and restore vegetation to sustain this particularly fragile ecological environment.  相似文献   

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