Optimizing the connectivity-carbon sequestration coupling coordination of forest and grassland ecological spaces (F & GES) is a crucial measure to enhance carbon sequestration effectively in mining areas. However, the prevailing strategies for optimizing F & GES often overlook the connectivity-carbon sequestration coupling coordination of the network. Therefore, this study aimed to propose a novel restoration plan to improve the connectivity-carbon sequestration coupling coordination of existing networks. Taking a typical mining area in northwestern China (Eyu County) as an example, we extracted the existing F & GES based on remote sensing ecological indicators and ecological risk assessments. Subsequently, we optimized the network using the connectivity-carbon sequestration coupling coordination degree (CSCCD) model from the perspective of connectivity carbon sequestration coupling coordination, proposed potential alternative optimization schemes, and evaluated the optimization effects. The results showed that the range of Eyu County's F & GES structure had been determined. Ecological source sites with better carbon sequestration effects were primarily distributed in the central and northeastern parts of Eyu County. After optimization, the network added 26 ecological patches, and the added area reached 641.57 km(2). Furthermore, the connectivity robustness, edge restoration robustness, and node restoration robustness of the optimized network were significantly improved, and the carbon sequestration effect of the forest and grassland ecological space was increased by 6.78%. The contribution rate of ecological source sites was 97.66%, and that of ecological corridors was 2.34%. The CSCCD model proposed in this study can effectively improve the carbon sequestration effect in mining areas, promote carbon neutrality, and save network optimization time while improving efficiency. This restoration strategy is also applicable to forest and grassland ecosystem management and optimization of ecological spaces in other mining areas, which has positive implications for promoting ecological civilization construction and sustainable development.

Littering in urban areas negatively affects their appearance, is harmful to the environment and increases pollution. It is a typical urban problem looming large upon Beijing and other megacities striving for liveability and harmony in economy, society and environment. This study analyzed the amount and spatial distribution of urban litter generation in Beijing based on the Kernel Density Estimation method and Anselin's Local Moran I method. We analyzed multiple factors affecting littering in urban areas based on the random forest machine learning method. The results show that the density distribution of litter presents a typical core edge diffusion spatial distribution pattern. High clusters of litter were found in most regions of Dongcheng District and central regions of Haidian District. We have verified that littering in urban areas is mostly affected by population, POIs (interest points), road networks, and the management of the city environment. Among these, permanent population, level of road cleaning, the presence of branch roads and commercial places are the four most important influencing factors. This study is of great significance to the prevention and treatment of littering in urban areas and can help city managers better address this problem.

Water conservation is an important part of the ecosystem service function. As a complex ecosystem, forests have different contributions to water conservation. The forest litter plays an important role in the water conservation function, for it directly covers the ground surface. Remote sensing and hyperspectral technology provide a solution for the long-distance detection of water conservation in planar areas. Especially in plateau areas, remote sensing is the most effective way to obtain surface information. In this paper, the hyperspectral data of main tree species were measured by ASD spectrometer in the Grand Canyon research area of Yarlung Zangbo. The litter samples were obtained by sampling on the plot and the water holding capacity of the samples was calculated. Use leaf spectrum information to construct vegetation index related to litter water conservation capacity, then establish multiple regression model of vegetation index and effective retention capacity, and invert the water conservation capacity distribution of main tree species in the Grand Canyon based on Sentinel-2 images. In the end, the accuracy of the inversion model is evaluated based on the verification points. The results showed that : (1) The reflectance of Quercusaqui folioides was the highest, the lowest was the Picea Linzhi, and the total reflectance trend of the three species was similar; (2) The effective interception amount of litter is sorted from large to small as follows: Picea Linzhi (48. 36 t . ha (1))> Quercusaqui folioides (39. 24 t . ha (1))> Pinus densata (32. 32 t . ha (1)). Picea Linzhi leaves are easy to decompose and store, Quercusaqui folioides' leathery leaves and Pinus densata's oily leaves are not conducive to decomposition. Therefore, the litter of Picea Linzhi has the highest effective interception amount. (3) Through the Person correlation coefficient analysis and the multiple linear regression model, it is found that the higher the wax parameters and attenuation degree of leaves, the weaker the water conservation capacity of litter; the better the vegetation growth trend, the higher the pigment and the water content of leaves, the stronger the water conservation capacity. (4) The results of the accuracy evaluation of the inversion model of the water conservation capacity of litter are good. R-2 of the test points of Pinus densata, Picea Linzhi and Quercusaqui folioides is 0. 943, 0. 815 and 0. 812, and RMSE is 1. 597, 2. 270 and 1. 953. It shows that the model can be used for the prediction and distribution of the water conservation capacity of forest litter in Grand Canyon.

[目的]快速的城市化发展导致景观破碎化和生态空间网络的破坏,因此合理构建生态空间网络可以促进生态源地之间能量的流动,有效缓解生态环境的恶化.[方法]以松花江流域为研究对象,基于土地利用数据提取生态源地,运用GIS空间分析技术和MCR模型,筛选生态源地及潜在生态廊道;其次,基于复杂网络方法计算生态源地"度",运用引力模型计算松花江流域潜在生态廊道"边权",依据复杂网络中"边权"和"度"得到研究区生态源地"权重";最后,通过权?度相关性对研究区生态空间网络进行模拟增边优化,分析生态空间网络鲁棒性.[结果](1)松花江流域生态空间网络由450个生态源地和1019条潜在生态廊道组成.(2)在松花江流域生态空间网络中,齐齐哈尔市、大庆市、松原市生态源地斑块聚集度低,生态廊道结构简单,呼伦贝尔市、牡丹江市斑块聚集度高,生态空间网络错综复杂.研究区生态空间网络出现两极分化,生态环境亟需优化.(3)基于复杂网络理论,对松花江流域进行模拟增边优化.共识别增边节点20个,模拟增边24条,模拟增边优化后,网络连接鲁棒性有了明显的增强,松花江流域生态空间网络连通性以及抗干扰能力有很大提升.[结论]基于MCR模型构建生态空间网络,运用复杂网络理论对松花江流域进行增边优化,提升生态空间网络的鲁棒性,为松花江流域生态空间格局优化奠定了理论基础.

In arid and semi-arid regions, vegetation restoration will have a significant impact on ecosystem services (ESs). Accurate assessment of the relationship and driving mechanism between ESs will play an important role in the implementation of subsequent vegetation restoration projects and ecosystem management. The purpose of this study is to evaluate and identify the relationship between ESs, and explore the impact and driving mechanism of ecological restoration on the relationship between ESs. Taking the middle reaches of the Yellow River as the study area, this study analyzed three ESs including: Net Primary Productivity (NPP), soil conservation (SC), and water yield (WY), in the vegetation restoration area (VRA) in the middle reaches of the Yellow River for 20 years (2000–2010 and 2010–2020 years(a)). Taking the ecological restoration unit (ERU) as the evaluation unit, we evaluated the impact of three vegetation restoration models on ESs. Using geo-detectors to identify the economic, social and natural drivers that affect the relationship between ESS. The results showed the following: (1) Different vegetation restoration models will lead to significant differences in the restoration rate for ESs. They will lead to an increase in the recovery rate of NPP and SC. The first vegetation restoration mode and the third planting restoration mode will reduce the restoration rate for the WY. (2) The three vegetation restoration models will enhance the synergistic relationship between NPP and SC. They will weaken the trade-off relationship between NPP and WY, SC and WY. (3) Temperature, precipitation, and NDVI will affect the changes in ESs in VRAs. The ESs trade-off-synergy relationship will be affected by precipitation, NDVI, and GDP. This study showed that, with the implementation of vegetation restoration projects, ESs in time and space and the complex heterogeneity of ESs will affect ecosystem management. The results of this study will be helpful for the implementation of subsequent vegetation restoration projects and provide scientific advice for ecosystem management.

[Objective] The ecological restoration strategy of sandy land in Gansu Province from a macroscopic perspective was investigated in order to provide a foundation for the construction and optimization of a regional ecological space network. [Methods] By combining the land desertification sensitivity index with ecological networks, nodes in areas with higher sensitivity were selected and optimized by increasing the edges through degree centrality and betweenees centrality analysis. The optimization results were verified by comparing the robustness before and after enhancing the edges. [Results] ① The sensitivity of land desertification in Gansu Province showed a spatial pattern of gradually decreasing from the northwest to the southeast, and the land desertification in the northwest was serious. ② The dense ecological sources and corridors in the southeast part of Gansu Province and the scarcity of sources and corridors in the northwest part indicated that the ecological network in the northwest was poorly connected, and the ecological background needed to be strengthened. ③ The node robustness and connection robustness of the ecological network after edge-enhanced optimization was significantly improved, while the robustness of network edges was slightly but not significantly improved. [Conclusion] The stability of the ecological spatial network in Gansu Province can be improved through the edge-enhanced optimization strategy, and the ecological self-restoration capacity can be enhanced. However, the simulated ecological restoration paths may not be suitably transformed or the actual costs of constructing corridors may be large due to geographical constraints, and circumstances should be considered specifically in light of the actual situation.

[Objective] The landscape ecological risk assessment and driving factors in the Ordos-Yulin area was analyzed, in order to provide a scientific basis for the management and restoration of the ecological environment and the construction of the ecological security pattern in this area. [Methods] Based on the land use data of Ordos-Yulin area in 2000, 2010 and 2020, ArcGIS 10.2 and Fragstats 4.2 software were used to construct a landscape ecological risk assessment model based on the degree of landscape disturbance and landscape vulnerability. The dynamic analysis of landscape ecological risks was carried out at spatial and temporal scale, and the driving factors of its changes were detected by using geographic detector. [Results] ① Grassland, cultivated land and unused land were the main land use types in Ordos-Yulin area, and the intensity and speed of land use was the most active from 2010 to 2020. Grassland was the main type of transfer in and out. ② From 2000 to 2010, the areas with medium ecological risk, high ecological risk and high ecological risk showed an expansion trend, while the low ecological risk and low ecological risk showed a contraction trend. From 2010 to 2020, the areas with medium ecological risk, higher ecological risk, and low ecological risk showed a contraction trend, while areas with low ecological risk and lower ecological risk showed an expansion trend; ③ The global autocorrelation analysis of Moran's I index in 2000, 2010, 2020 was greater than 0.8, showing a significant positive correlation in spatial distribution. Most ecological risk units presented high-high and low-low distribution, and a small number of ecological risk units were high-high and low. The distribution around the low-risk unit indicated that the ecological risk in the study area was relatively stable. ④ According to the analysis of geographic detectors, the degree of human disturbance had a strong explanatory power for landscape ecological risks, followed by NDVI. Various ecological protection activities directly promoted the improvement of NDVI. [Conclusion] Landscape ecological risks in Ordos-Yulin area are mainly affected by human activities, and human activities mainly ecological protection activities, can effectively reduce ecological risks. Accordingly, ecological protection measures should be strengthened to promote ecological security patterns in Ordos-Yulin area.

The phenomenon of fly-tipping of bulky waste is becoming increasingly serious with the development of economy and the improvement of living standards. The fly-tipping of bulky waste causes a waste stream with a high proportion of good quality recyclable materials and a wide range of social and environmental problems including damaging the environment and aggravating traffic in a megacity like Beijing. In this study, we analyzed the quantitative spatial distribution of fly-tipping bulky waste in Beijing for the first time and identified its driving forces to explore the fly-tipping rule of bulky waste. We used Anselin's Local Moran I method to reveal the spatial characteristics, and Random Forest machine learning method to examine the driving factors based on multiple data sources such as geographical, population and survey data. The results showed that the spatial agglomeration of fly-tipping presented a typical core edge diffusion spatial distribution pattern. High-High clusters of cases were found in most regions of Dongcheng District and the east part of Xicheng District. In the multifactorial drivers, the three most important driving factors were found to be accommodation, floating population and income level. Surprisingly, any kind of road and educational level had small effect on the fly-tipping case. These results provide a theoretical basis for the government to advance comprehensive prevention and control strategies of bulky waste fly-tipping. And it is helpful to formulate management policies of fly-tipping bulky waste and provide targeted guidance and suggestions for senior decision makers and managers.

“Two ecological barriers and three shelters” (TEBTS), which has the effect of relieving ecological pressure, is the national ecological security pattern in China. Calculating the value of TEBTS ecosystem services, clarifying the synergy/trade-off relationships between ecosystem services, and maximizing the value of regional ecosystem services are of great significance for maintaining the security of the ecological civilization. At present, the research on ecosystem service synergy/trade-off has become the frontier field of ecology and related disciplines at home and abroad, and many research results have been obtained. However, there is still room and significance for continuing research to think about the synergy/trade-off relationship of ecosystems from the perspective of temporal and spatial heterogeneity: clarifying the spatial scope and spatial transmission characteristics of ecosystem service synergy/trade-off; exploring the trend of ecosystem service synergy/trade-off, and simulating the dynamic characteristics of natural factors affecting ecosystem services; and analyzing the characteristics of different spatial attributes that lead to the synergy/trade-off of ecosystem services. In this study, the Songhua River Basin (SRB), where the NFB is located, is used as the research area, the ecosystem services are simulated through the ecosystem assessment model, ecological unit (EU) is constructed as a research carrier, which is used to define the spatial scope of ecosystem services, and the influence of spatial characteristics and attribute characteristics on the change trend of the ecosystem service synergy/trade-off relationship is analyzed. The research found that water retention, soil conservation, and biodiversity did not change much from 2000 to 2015, and these ecosystem services have a greater value in the NFZ. The amount of carbon sequestration increased rapidly from 2010 to 2015. Crop production showed an increasing trend year by year. As the main grain production area, the Songnen Plain provides the main crop production function, which is greatly affected by humans. In the spatial characteristic, water retention, soil sequestration, and biodiversity present a very significant synergistic relationship, which is manifested in the obvious high-value aggregation characteristics in the NFZ, and crop production and the other four types of ecosystem services are in a trade-off relationship. At the time scale, the four types of ecosystem services, including water retention, soil conservation, biodiversity, and carbon sequestration, are synergistic, and crop production and water retention are synergistic. The vegetation types exhibiting a synergy/trade-off relationship are mainly broad-leaved forests, and the soil types are mainly luvisols and phaeozems. These EUs are mainly distributed in the NFZ and have spatial topological characteristics: the area and circumference of these EUs are smaller, the radius of gyration is also significantly smaller than that of other EUs, and the shape is more regular. By focusing on the spatial aggregation characteristics and changing trends of the ecosystem service synergy/trade-off and clarifying the influencing factors of the ecosystem service synergy/trade-off, the ecosystem services can be integrated, and the ecosystem can be optimized. Thus, the value of regional ecosystem services can be maximized, and a certain data foundation and theoretical support can be provided for major projects, such as ecological restoration and ecological environment governance, which is of great significance for improving the pattern of ecological security.

Carbon neutrality is a long-term climate goal in the context of global warming and can be achieved by reducing carbon emissions and increasing carbon sinks. Vegetation has a very important and irreplaceable role in increasing carbon sinks, but it is often destroyed, especially in desertification and mining areas. Therefore, restoration of the vegetation in these areas is essential. Seeking the optimal solution for landscape spatial structure through adjustment and optimization can promote ecological processes, improve environment and soil conditions on a large scale, provide favorable conditions for vegetation growth, and is an effective way to achieve vegetation restoration to increase carbon sinks. Here, a targeted landscape spatial structure optimization scheme called EFCT model was developed for complex ecological situation of Ordos, with the goal of increasing carbon sinks to achieve carbon neutrality. The scheme identified areas where the landscape spatial structure needs to be optimized and the direction of optimization based on the differences in the synergy degree between ecological function and connectivity of the patches. The study also compared the carbon sink function and robustness of the landscape spatial structure before and after optimization according to the scheme. The results show that the patches in the landscape spatial structure of Ordos form four separate clusters distributed in a differentiated east-west part of the structure, with higher ecological function and poorer connectivity in the east and the opposite in the west. In the landscape spatial structure optimized by the EFCT model, the ecological function of 42 patches was enhanced, and 19 patches and 44 corridors were added. The total carbon sink in the optimized structure increased by 31.51% compared to the unoptimized structure, mainly due to the improved ecological function of the grassland patches in the western structure, in addition to the carbon sink contribution of the new patches and corridors. At the same time, the connectivity between the four clusters had been enhanced and the structure was more coherent and stable.

为探究京津冀城市群树木覆盖率(TC)、短植被覆盖率(SV)与裸地覆比率(BG)变化趋势及生态空间格局对地表温度的影响,基于京津冀城市群的MODIS遥感数据,运用景观生态学理论并结合空间计量经济学相关原理研究了京津冀生态空间与地表温度的格局特征,运用Pearson相关性探究了两者的相关性,分别运用空间双变量自相关与空间自回归模型探究了两者的空间相关性.结果表明:京津冀地区中部、东北部以及西南边界地区的树木覆盖率呈现增长趋势,东北、西南边界和东部沿海地区的短植被覆盖率呈上升趋势,承德市西北部和南部、保定市、石家庄市、邢台市和邯郸市的部分区域具有土地裸露风险.提取了京津冀城市群的绿色空间和蓝色空间,各样区内蓝绿空间与地表温度的空间分布具有显著的空间自相关性.样区5、7位于河北省北部,林地景观比例较高,相关性以及双变量空间自相关性高于其他样区,这与景观优势度、斑块破碎度有关.样区1、4生态空间比例较低,对地表温度影响有限.景观类型比例对地表温度影响较大,样区7的生态空间比例较高,并且生态空间斑块集中连片,对地表温度影响明显.样区1～7的空间滞后模型与空间误差模型拟合效果远优于OLS模型.各个样区空间误差模型的R2大于空间滞后模型,空间误差模型解释变量的能力更强.各个样区空间误差模型的LIK值较大,AIC、SC以及模型残差的Moran'sI值较小,空间误差模型的拟合效果优于空间滞后模型.

[目的]叶面滞尘会影响植被光谱特征,削弱植被指数对植被的响应能力,影响反演评估的准确性.为探究叶面滞尘量对植被光谱响应特征及预测模型的影响,本文以北京市常见常绿绿化树种大叶黄杨为研究对象展开研究.[方法]从封闭区域、半封闭区域、开放区域,采集叶片样本,并收集环境灰尘.通过室内控制试验,利用ASD?FildSpec?Handheld光谱仪测量不同滞尘量叶片的高光谱数据,选取5个特征波段,通过光谱角的方法研究了叶面滞尘量对叶片光谱特征的影响,以及滞尘量对叶面滞尘量预测模型的精度和稳定性影响.[结果]随着叶面滞尘量的增加,植被光谱曲线特征逐渐减弱,灰尘的特征逐渐增强,但光谱曲线的总体变化趋势基本一致.当叶面滞尘量?>?120?g/m2时,光谱曲线的基本表现为灰尘的光谱特征.当叶面滞尘量较少时,预测模型的模拟精度相对较高,随着滞尘量的增加,所有模拟预测模型的决定系数均减小;当叶面滞尘量?>?120?g/m2时,预测模型对叶面滞尘量的模拟预测能力将更差,并且均方根误差(RMSE)随着叶片单位面积滞尘量的增加而增大,模拟预测模型的稳定性及预测精度逐渐降低.光谱角对滞尘叶片350?～?1770?nm波段区间的光谱变化十分敏感,利用叶片光谱角检测滞尘程度不需要分区域讨论,只需与阈值做简单的比较,方法简便易行.[结论]本研究通过室内控制试验,研究叶面滞尘量对植被光谱响应特征,可为建立滞尘植被光谱反射物理模型提供参考与借鉴.

在分析鄂尔多斯市生态空间网络拓扑结构和鲁棒性的基础上,提出节点最低和最大介数增加(Low and maximum betweenness addition,LMBA)增边优化策略,同时与采用RA、LDF和SMB 3种增边策略的优化结果进行了对比.结果表明:鄂尔多斯生态空间网络有262个节点、402条边,网络直径为38,节点最大介数为418,最大连通度为25.网络连通度低,重要节点少且均位于网络西部,网络极不均匀,当网络结构遭到破坏时,进行自我恢复的能力比较强,但维持自身连通性的能力非常弱.增边94条后,LMBA策略优化后网络直径为16、节点最大介数为796、最大连通度为49,网络重要节点增多,网络整体效率明显提升;RA、LDF策略也使网络连通度极大增强,SMB策略的网络连通性增强效果不显著,重要节点增多且东移,网络结构比优化前更均匀.遭到攻击后,网络的连接鲁棒性大大增强,恢复鲁棒性也有所提升.与其他策略对比,LMBA策略的连接鲁棒性在两种攻击模式下、节点恢复鲁棒性在随机攻击模式下表现最优,节点恢复鲁棒性在恶意攻击下、边恢复鲁棒性在两种攻击模式下表现较优且稳定,说明该策略网络连通性强、结构均匀,综合表现最优.在遭受攻击过程中,LMBA策略维持自身连通情况的能力较优且稳定,节点和边的恢复能力也较优.

如何保障黄河流域煤矿开采与生态环境的协同发展,建设黄河流域生态文明,是当前研究的重要课题.选取黄河流域典型矿区——鄂榆矿区为研究区,基于复杂系统与景观生态理论,结合景观生态风险评价与复杂网络分析2种方法,从宏观角度探究矿区生态修复策略.首先对研究区进行潜在复杂生态网络的提取与景观格局生态风险评价;然后识别研究区潜在复杂生态网络中处于中高生态风险区且其度中心性较低的生态节点,进而基于复杂网络增边优化理论,结合研究区当地的矿区与景观分布情况,进行模拟增边优化,最后通过对比分析模拟增边优化前后研究区潜在复杂生态网络的鲁棒性,验证模拟增边优化的效果.得出:中高生态风险区域主要分布在南部、北部的耕地区域与东北部的矿区;提取得到潜在复杂生态网络生态源地共77个,生态节点109个,生态廊道193条;识别增边优化节点共10个,最终成功为其中7个节点进行模拟增边共6条,另有3个节点模拟增边失败;模拟增边优化后,网络的连接鲁棒性较优化前有显著提升,网络的节点恢复鲁棒性与边恢复鲁棒性略有提升.从结果来看,模拟增边优化能够有效加强研究区生态质量,为矿区生态修复区域提供宏观上的参考与借鉴.

To reveal the main natural factors that influences groundwater depth of Dengkou county and predict the variation trend of groundwater depth, this thesis, based on the principal component analysis (PCA), conducts analysis on natural factors that are likely to affect the groundwater depth, and establishes a multiple linear regression model to show the quantitative relationship between the main natural factors and the groundwater depth. Then grey prediction method is adopted to predict possible change of main natural influence factors in the coming five years with employment of multivariate regression equation for further fitting. Results: Among the selected natural influencing factors, the most influential one is evaporation, followed by air temperature and sunshine hours, which are negatively correlated with groundwater depth, and the reason for this is related to the flood season of Yellow River. Relative humidity and precipitation have little influence on groundwater depth. According to the grey prediction results, the temperature, evaporation and sunshine duration will all be on the rise in the coming five years, and the average groundwater level will also increase slowly. The average depth of groundwater in summer is about 2.5m. Due to local dry climate and vigorous evaporation, secondary salinization of the land is likely to occur. Especially, the water level in the irrigation area of the Yellow River is generally high, deserving enhanced vigilance. This paper has reference significance for the ecological construction & planning of Dengkou County in the next five years.

以鄂尔多斯市为典型研究区,以2000、2005、2010、2015、2018年研究区景观格局数据和气象水文数据为研究素材,基于复杂网络理论、景观生态学和GIS空间分析技术,定量研究鄂尔多斯市景观格局的时空演变规律,并探究各级子流域的水源涵养深度,再将研究区景观格局演变数据和生态水文数据与由多个决定景观特征的因子构建的景观生态网络进行耦合分析,为研究区景观格局优化及生态环境建设提供参考.结果 表明:在研究期内鄂尔多斯市的耕地不断减少,林地、草地、水域和建设用地均有一定程度的增加;景观演变主要是耕地、林地和水域之间的转化,林地、水体的景观演变最为剧烈,耕地、草地和建设用地相对平稳;鄂尔多斯地区整体水源涵养能力偏低,相对而言,东部地区的水源涵养能力高于西部地区,随着时间的推移,水源涵养深度高值逐渐南移;构建的鄂尔多斯市景观生态网络共342个生态节点、402条生态廊道,基于度低者优先的增边策略增加了119条廊道;优化后的网络连通度和连通鲁棒性均明显提升,网络中生态流更为畅通.

以内蒙古自治区赤峰市翁牛特旗为研究区,采用2008、2013、2018年相同月份的遥感影像,结合翁牛特旗地区土地利用数据,将景观类型分为耕地、林地、草地、水域、建设用地和未利用地6类,进行景观格局指数分析,选取6个景观类型水平指数和6个景观水平特征指数,分析不同粒度对景观格局各指数的影响.研究结果表明:在景观水平格局指数中,斑块密度从0.40个/hm2下降到0.32个/hm2,香农多样性从1.37增加到1.45,香农均匀性从0.76增加到0.81,说明尚未形成优势景观,景观破碎度加剧;在景观类型水平上,随着粒度的变化斑块面积百分比没有明显变化,其他景观类型均随粒度的变化而变化.其中,在2013年和2018年水域对斑块密度的粒度效应反映较为强烈,分别从0.005个/hm2增加到0.046个/hm2、从0.010个/hm2增加到0.046个/hm2;未利用地对有效网格面积的粒度效应反映较为强烈,从24596 m2增加到40697 m2;建设用地对聚集度、凝聚度的粒度反映较为强烈,分别从0.9减少至0.3、从94％减少至49％.

A scientific and reasonable ecological compensation scheme (ECS) is an important guarantee for promoting coordinated and equitable development between regions. The existing ECSs usually ignore the premise that the ECS can only be accepted by the stakeholders if there are a clear scope and benefit to the ecosystem services (ES). An ecological compensation scheme should be based on the transmission principle of ES so that a scientific and reasonable scheme can be proposed and accepted by the stakeholders. Based on the theory of ecosystem service flow, this paper analyzed the provision‒benefit mechanism of sand-stabilization ecosystem service (SSS) and selected Ordos City, Inner Mongolia, which is located in Northwest China, as the study area. A revised wind erosion equation (RWEQ) model was used to estimate the sand-stabilization amount of Ordos’s ecosystem in 2015, and a hybrid single-particle Lagrangian integrated trajectory (HYSPLIT) model was used to simulate the path of sand-stabilization ecosystem service flow (SSSF). Then, the benefit areas and levels of SSS were identified, and the spatial distribution of land cover, population, and gross domestic product (GDP) in the ecosystem services beneficiary area (SBA) was evaluated. Based on the identified benefit areas and benefit levels, and combined with the investment and income in the ecological construction of the Ordos, a cross‒regional differentiated ECS was proposed. The results show that the Ordos’s ecosystem played a huge role in sand-stabilization, which have brought huge ecological and economic benefits. In 2015, the sand-stabilization amount of Ordos’s ecosystem was about 7.20×108 tons. The area of SBA is1.66×106Km2, accounting for 17.21% of China’s total area, this mainly involves 16 provinces and cities, including Beijing, Tianjin, Hebei, etc. The amount of dust‒fall (ADF) in the beneficiary area was reduced by 28,738.67 ×104 tons, and investment of 4318.51 ×108 RMB (Renminbi) in dust removal would be avoided. For the ECS, based on the principle of “equity, beneficiary compensation, more benefit and more compensation”, Ordos shall take care of the ecological compensation fee (ECF) of about 36.28% of the total. In 16 provinces and cities, Inner Mongolia costs 66,121.03 ×104 RMB, which is the most. The fees are payable by other SBAs decrease with distance. Hubei Province (Suizhou) pays the least in ecological compensation, at 7.5 ×104 RMB. Based on the theory of ecosystem service flow, this paper proposes a research framework of differentiated ECS of SSS, which can provide an accurate scientific basis for determining the SBA and cross-regional ECS of SSS in the future.

以内蒙古自治区赤峰市翁牛特旗为研究区,计算不同粒度下的景观格局测定指标,综合粒度反推法与主成分分析法识别得出3 200 m为最优粒度,依据最优粒度景观特征选取生态源地51个.结合地区特征构建生态阻力面,提取生态廊道49条、生态节点58个,对廊道、节点进行密度分析.结果 表明,翁牛特旗东西部生态状况存在显著差异,西部中、低山丘陵区源地、廊道集中,存在3处高节点密度区需要重点加强保护建设,东部平原区沙地广布,源地、廊道分散,能量流通主要依赖西拉沐沦河与老哈河,生态结构连通性差.基于最优粒度提取生态源地综合考虑了景观连通性与尺度效应,较传统方法更加科学、客观,可为区域景观格局优化提供参考.

Urban forests affect the filtration and adsorption of airborne particulate matter, which can minimize the harmful effects on human health caused by airborne particulate pollution. Evergreen plants in urban forests play a major role in absorbing dust and purifying the air, especially in winter. In this study, Euonymus japonicus , the main evergreen vegetation in winter in Beijing, was used as the research object. Three types of sampling space were set up, and 1 410 leaves were collected to measure the hyperspectral data before and after cleaning and the amount of dust absorption (ADA) on the surface of the leaf. The sensitive band was determined by analyzing the response of spectral reflectance to the amount of dust retention, and the regression model was established between the vegetation index ratio and ADA before and after cleaning. The Sentinel-2 remote sensing image was used to obtain the dust distribution of the evergreen vegetation, and the inversion results were verified. The result showed that in the range of 510 similar to 700 and 758 similar to 1 480 nm, the average spectral reflectance of the blade before dust removal is less than that of the clean blade. The change of average spectral reflectance before and after cleaning in the closed zone is less than that in the semi-closed zone, and the change in the open zone is the largest. And the red band and nearinfrared band are most sensitive to dust. The inversion model established using the Normalized Difference Phenology Index (NDPI) is : x=0. 939 69 y (0.)(145)( )(04) (x represents the value of R-NDPI , and y represents the amount of dust retention), and the determination coefficient (R-2) reached 0. 879. The inversion results show that the mean ADA in the enclosed area is smaller than that in semi-enclosed and open areas, and the regional distribution of high ADA in the urban area of Beijing was higher in the south with a tendency of the ADA to decrease from city centre to the surrounding area. Study the spatial distribution of leaf dust retention and provide a reference for rapid monitoring of dust pollution intensity and distribution in urban areas, and exploring the dust retention effect of evergreen shrubs are important for scientifically guiding urban forest construction and improving the living environment of cities in winter.