Photothermal superhydrophobic surfaces are prospective for energy-efficient anti-icing/deicing, yet challenges remain in controlling their formation mechanism and ensuring the long-term stability of their micro−/nano structures. To overcome these limitations, a durable superhydrophobic coating is demonstrated via a scalable scraping and hot-pressing method based on the two amorphous polymers. Remarkably, employing fluorine-free component epoxy resin (EP) and liquid silicone rubber (LSR) as model polymers with contrasting polarities, a robust superhydrophobic composite with hierarchical micro−/nanoscale architectures is reported through a process of phase separation followed by controlled swelling procedure. The EP component ensures strong substrate adhesion and mechanical stability of micro−/nano structures, while the LSR imparts low-surface-energy, delaying ice nucleation. The resulting EP@LSR-SC sample demonstrates exceptional endurance, withstanding a nonlinear wear distance of 5000 cm under 600 g load, along with resilience to linear abrasion, UV exposure, sands impact, tape-peeling, and physical-chemical treatment. By further incorporating carbon black (CB) as a photothermal agent, the as-prepared EP@LSR@CB-SC sample attains a rapid temperature increase to 77 °C within 300 s under 1 sun illumination, enabling effective ice melting. In an outdoor test at −15 °C, the simulated house model coated with EP@LSR@CB-SC can remain ice-free for over 40 min and rapid photothermal de-icing stage. The as-prepared coating is low-cost owing to its simple preparation, can be widely used for anti-icing and de-icing of buildings.

As a promising strategy for protecting outdoor power transmission insulators, superhydrophobic coatings have demonstrated great effectiveness in suppressing interfacial leakage currents, mitigating insulator aging induced by rain, fog, and ice accumulation, and thereby extending their service life. Current strategies face significant limitations: lithography or 3D printing can produce ordered micropatterns, they are prohibitively expensive at the nanoscale, whereas disordered micro/−nanostructures suffer from irreproducibility and poor mechanical stability. This study develops a flexible, photothermal and spliceable superhydrophobic coating with excellent mechanical stability for long-term anti-icing and active deicing applications. Polyurethane (PU) is used as the first layer of elastic matrix in which tire rubber powder (TRP) is incorporated as a micro-structural builder to acquire the PU@TRP roughened surface. Finally, modification with polymer-based low-surface-energy substance (i.e. liquid silicone rubber) has realized the functionalized fabrication of PU@TRP superhydrophobic coating (PU@TRP-SC) with three layers of flexible design. The as-prepared PU@TRP-SC coating exhibits excellent mechanical durability, physicochemical stability, flexibility, and substrate adaptability. In particular, the PU@TRP-SC coating maintains superhydrophobicity after 400 abrasion cycles under a 2 kg load (equivalent to a total wear length of 80 m). Under 1 sun irradiation (1 kW‧m−2), the coating achieved rapid photothermal conversion, reaching a surface temperature of 61.0 °C within 400 s, which facilitates efficient sunlight-driven ice removal. After 90 days of outdoor exposure of repeated rainfall, dust accumulation, and temperature variations, the PU@TRP-SC coating retains a water contact angle above 150°, indicating great potential of practical application for outdoor insulators protection.

Despite substantial efforts dedicated to achieving the Sustainable Development Goals (SDGs) by 2030, there remains a critical lack of focus on how the nonlinear interactions between the SDGs affect their progress. To fill this pressing knowledge gap, we conducted a comprehensive analysis of SDG interactions and progress in China, from 2000 to 2021, with a focus on assessing nonlinear interactions and their effects on compound annual growth rates of SDGs at both national and provincial scales. Our results show that unless its current trajectory improves, China will not fully achieve all SDGs by 2030, with actual growth rates of some of the goals falling short of desired targets. Crucially, nonlinear interactions among SDGs are more prevalent than linear ones, calling into question the conventional assumption of predominantly linear interactions. While linear synergies do exert the strongest positive influence on SDG progress, the unclassified interactions emerge as the most critical factor inhibiting it. Our findings emphasize the importance of adopting more tailored policy approaches that leverage beneficial nonlinear dynamics and tackle obstacles posed by isolated actions or trade-offs, thus offering valuable insights for both China and the global community in navigating the complexities of the timely achievement of the SDGs.

The corrosion of reinforced concrete materials severely threatens cross-sea bridges, buildings and marine ships. The unique air layer on the superhydrophobic coating surface can effectively minimize the reinforced concrete corrosion, which not only extends the long-term usability of concrete but also reduces economic losses and environmental pollution. It is necessary to design a superhydrophobic coating on substrate surfaces to accommodate the requirement for corrosion prevention due to their anti-corrosion and self-cleaning properties. Despite gradually developing superhydrophobic coatings to meet diverse needs, they still encounter limitations in engineering preparation and applications. For example, the rough micro-/nano structure of the superhydrophobic surface is easily damaged by mechanical impact or physicochemical damage, which could affect the antiseptic properties. Moreover, designing and preparing all polymer-based superhydrophobic micro-/nano structures using amorphous elastomer materials is vital for enduringly industrial applications, yet it remains a challenge. Here, we design and fabricate a mechanical-robust superhydrophobic coating composed of amorphous polyurethane (PU) and epoxy resin modified with amino-terminated polysiloxane (APT-PDMS) via a scalable atomization spraying method. A quartz sands impact abrasion test evaluates the mechanical durability of the PU superhydrophobic coating (PU-SC). The superficial PU particles can form elastic micro-protuberances, absorbing impact and preventing fracture through elastic deformation during friction. Furthermore, the as-prepared PU-SC can also resist some chemical mechanical damage, including acids/bases/salts solution corrosion, UV radiation, knife scraping treatment, 3M tape-stripping, water flow impact, outside sunlight shining treatment and temperature treatment. Notably, the robust PU-SC can be efficiently produced on a large scale and applied to prevent electrochemical corrosion in a simulated seawater environment. The corrosion protection efficiency (PE) can reach 98.1%. We believe that the design and development of a mechanical-robust and polymer-based superhydrophobic coating has the prospect of actual application on marine corrosion.

Superhydrophobicity exhibited by several natural surfaces has broad application prospects due to their excellent self-cleaning and low adhesion properties. However, designing a robust superhydrophobic coating via design strategy using amorphous polymers is allimportant for industrial applications, yet rather challenging. Here, we report a scalable strategy based on the phase separation and swelling treatment to construct an ultra-durable superhydrophobic coating with hierarchical micro-/nanostructures formed by two amorphous polymers (e.g. hydrophilic and lipophilic polymers). The controlled phase separation of two amorphous polymers creates uniformly distributed microprotrusions on the coating surface and the following swelling process produces submicro-/nanobumps on the microprotrusions. Notably, when both types of polymers achieve the hierarchical micro-/nanostructures, hydrophilic polymers exhibit strong adhesion with the substrates, whereas lipophilic polymers reduce the surface energy of the system. Benefitting from the self-similar structure and the adhesive effect, the polymer-based superhydrophobic coating displays superior mechanical and chemical robustness. Furthermore, our strategy will boost the practical application of robust superhydrophobic coatings for anti-corrosion application.

Assessment of habitat suitability and identification of the driving factors are crucial to the protection and management of species and their habitats,and also are the premise and basis for biodiversity conservation planning.In this study,the distribution of key habitats and their suitability in Xianju National Park pilot area of Xianju Coun-ty were evaluated using a MaxEnt model based on species occurrence data for large mammals and rare birds sourced from field investigations.Furthermore,the main driving factors and their contributions to habitat suitability were analyzed.The conservation gaps were identified by overlaying these variables on current distribution of protected areas.Finally,suggestions for future regional biodiversity protection and planning are proposed.The results showed that mean value of the area under the curve(AUC)for the 13 target species was 0.956,indicating that the outcome of the MaxEnt model used in this study was reliable.Human population density,mean temperature in the wettest quarter,and land use types were the main factors affecting habitat suitability for mammals.The annual temperature range and mean temperature of the wettest quarter were the main factors affecting the distribution of pheasants,while altitude and slope were the main factors affecting the distribution of suitable areas for wetland birds.In terms of habitat distribution,suitable areas for mammals and pheasants were mainly located around Kuocang Mountain in the south of Xianju County,while suitable areas for wetland birds were located near the Yong'an River.Currently,the protected areas in Xianju County are 316.80 km2,while the suitable habitats located outside the existing protec-ted areas are 160.37 km2 for mammals,178.67 km2 for pheasants,and 422.65 km2 for wetland birds,indicating some conservation gaps within the current protected system.We suggest the strengthening of biodiversity protection in Xianju County in conjunction with the construction of the Xianju National Park pilot area,which can provide a theoretical basis and best practice guidelines for regional sustainable development.

The Loess Plateau of China is facing increasingly serious challenges related to water shortage issues despite the successful vegetation restoration. Surface soil water (0–40 cm) is crucial to water transfer and discharge in the soil-plant-atmosphere continuum, which is controlled by precipitation (P), air temperature (T a ), and plant components. This study selected one typical grass species and set different treatments of natural condition (NC), removing litter (CR), and only roots (OR), to analyze the responses of soil water storage (W) and its change (∆W) to P and T a at different time scales (including daily, weekly and monthly scales). The results showed that P had significantly positive effects on W and ∆W, while T a negatively influenced W and ∆W. Meanwhile, T a also controlled the significance of P affecting W. P contributed more (53–63%) to ∆W variation at the daily scale, but T a showed more effect (73–80%) at the weekly scale, and both of them contributed more than 77% at the monthly scale. P and T a existed a threshold phenomenon for increasing soil water, where P thresholds were higher than 0.93, 4.98, and 28.17 mm and Ta threshold were lower than 28.69, 28.89, and 29.96°C at the daily, weekly and monthly scales, respectively. Moreover, grass components also affected the responses of ∆W to P and T a , and the OR treatment displayed the lowest sensitivity and had the lowest loss rate of soil water. The total infiltration, total loss amount, and rainwater retention rate exhibited: NC > CR > OR. Overall, grass canopy and litter improved soil water condition, and the roots most strongly protected soil water after infiltration. This study can provide a better understanding of surface soil water responding to climate change under drought stress with water shortage implications, and may strength the management of grassland in semi-arid region.

干旱区生态系统的水文连通性影响植被斑块形态的空间分异.植被形态对水文连通性的适应是一个复杂且长期的过程.研究植被与水文连通性,过去多基于群落以上尺度,不涉及微观尺度.从植株个体角度探讨植被斑块形态与水文连通性关系,有助于挖掘微观尺度上景观格局对生态过程的驱动机制.本研究以黄土高原丘陵沟壑区多年生灌丛作为研究对象,以高分辨率无人机航拍照片解译和野外定点观测为研究手段,量化植被斑块形态与水文连通性之间定量关系,分析二者对泥沙截留与土壤固碳等关键生态过程的影响.结果表明:(1)坡面灌丛斑块总体呈现横向生长趋势,灌丛斑块纵横比小于1;灌丛斑块纵横比从坡顶到坡底逐渐增大,分别为0.64、0.70、0.79、0.83;(2)灌丛方向与水流方向夹角从坡顶到坡底先减小再增大;坡面中部的坡度最大,灌丛方向最接近与水流垂直的方向;(3)灌丛的汇流累积量从坡顶到坡底逐渐增大,表明其水文连通度逐渐增大;水文连通度与灌丛斑块纵横比呈正相关关系;当水文连通度足够大时,灌丛在横纵方向上的生长没有倾向,形状近似为圆形;(4)泥沙拦截量和固碳效率随坡位下降而下降,二次曲线拟合表明泥沙拦截量和固碳效率随水文连通度增加呈增加态势,表明水文连通度有促使植株自主优化株型、提升泥沙截留和固碳效率的功效.本研究有助于为黄土高原干旱区植被结构优化及生态建设提供案例分析与借鉴.

在晋西北偏关县天峰坪镇蹄子沟和井沟对小叶杨(Populus Simonii)暴露根系进行采样,通过分析根系导管细胞面积变化,判断出根系开始暴露的时间,并结合土壤表面高度变化信息,用基于根系年轮的土壤侵蚀测算方法计算土壤侵蚀量及速率.结果表明:蹄子沟和井沟的平均土壤侵蚀量分别为7.77和14.00 mm;平均侵蚀速率分别为1.11和3.35 mm/a.分析表明:造成研究区土壤侵蚀的主要因素为降雨和风速,但风速的影响更大;暴露根系导管细胞面积会随降雨量和风速的增大而减小.

Ecosystem services are generated by ecological processes over a range of scales. Studying the scale effects on ecosystem services is important for exploring the driving mechanisms and conducive to prudent ecological managements. Unfortunately, quantitative testing the scale effects of ecosystem services' associations, as well as identifying the driving mechanisms across scales, has rarely been documented. This study used the Loess Plateau as study area to test the scale effects and the correlations between sediment retention, water yield, and net primary production (NPP) and their driving mechanisms. A model of Integrated valuation of Ecosystem Services and Tradeoff 3.0 and the Carnegie‐Ames‐Stanford Approach were used to assess the services of sediment retention, water yield, and NPP in 2000 and 2008. Canonical correlation analysis (CCA) was used to quantify the driving mechanisms of ecosystem services. The results indicated that the ecosystem services are more varied in spatial patterns at small scale than at large scale. The average values of sediment retention, water yield, and NPP at small scale increased during the period. However, at large scale, the average values of sediment retention and water yield decreased and the NPP value increased simultaneously. Generally, the correlations between ecosystem services weakened when the spatial scale increased. The results from CCA indicated that, at small scale, the natural factors of precipitation, hours of sunshine, and temperature were the principal driving factors underlying ecosystem services. When the scale increased, the socioeconomic factors of population, grain production, and nonfarming production were gradually integrated into the factors driving the patterns of ecosystem services.

以汾河上游流域为研究区,综合运用网格分析法和景观生态学与生态系统服务相关理论,基于ArcGIS和GeoDa方法分析了2000、2008和2015年土壤保持、产水量和植被净初级生产力(NetPrimary Productivity,NPP)三种生态系统服务时空变化特征与景观格局的空间分异规律,定量分析了景观破碎化与生态系统服务的空间相关性.结果 表明:(1)2000 2015年,土壤保持与产水量均整体呈现先增加后减小的趋势,空间分布变化比较明显;NPP生产呈现持续增加的趋势.(2)2000-2015年,流域西南部景观格局变化最为明显,其破碎化程度增强,而流域北部景观格局破碎化程度减弱.(3)2000-2015年,土壤保持、产水量与景观破碎化呈现显著空间相关关系(P＜0.05),NPP生产与景观破碎化的空间相关性相对较弱.

随着社会经济的发展,人类对生态系统服务选择的加剧,生态系统服务面临的形势更加严峻.以汾河上游流域为研究区,以遥感影像、气象、土壤、统计数据及专题地图等为数据源,基于ArcGIS平台,采用CASA、InVEST等模型,评价了2000年和2008年汾河上游流域泥沙截持、产水量、NPP、固碳释氧、粮食生产五项生态系统服务变化情况;同时,整合人口、居民点、道路定量评价了研究区2000和2008年人类活动强度,并采用SPSS典型相关分析方法(CCA),对生态系统服务的自然与人文驱动因素进行了分析.结果表明:2000-2008年间,研究区5项生态系统服务变化明显.其中,泥沙截持服务减少43.30 t/hm2,减少范围占整个流域87.5％,只有北端局部区域有所增强;产水服务增加4.74 t/hm2,产水服务增加的区域占到了流域总面积的89.6％:NPP生产服务增加0.86 t/hm2,NPP增加的区域占研究区的93.7％,仅边缘零星区域NPP减少;固碳释氧服务与NPP生产服务呈现一致的时空格局,增加量达2.18 t/hm2,仅流域边缘零星分布减少的斑块;粮食生产服务总体上有所降低,下降幅度为15.65 kg/hm2,粮食生产减少的区域占到整个流域的65％.同期,该区域人类活动强度有所增强,人类活动指数(HAI)由0.19增加到0.21,呈现出北低南高的空间格局.相关性分析表明,2000-2008年前,人类活动与泥沙截持和产水服务呈现极显著的正相关(r=0.637**和r=0.656**).典型相关分析则(CCA)表明:影响泥沙截持服务的主要驱动因子是坡度,影响产水量的主要因素是降雨量和温度;2000-2008两年间生态系统服务变化量的典型相关分析表明泥沙截持和产水服务受日照时数、相对湿度、降雨等自然因子的影响,NPP生产/固碳释氧的主要影响因子为温度和坡向.

Soil provides various indispensable ecosystem services for human society. Soil's complex structure and property makes the soil ecological processes complicated and brings about tough challenges for soil ecosystem services study. Most of the current frameworks on soil services focus exclusively on services per se, neglecting the links and underlying ecological mechanisms. This article put forward a framework on soil services by stressing the underlying soil mechanisms and processes, which includes: 1) analyzing soil natural capital stock based on soil structure and property, 2) disentangling the underlying complex links and soil processes, 3) soil services valuation based on field investigation and spatial explicit models, and 4) enacting soil management strategy based on soil services and their driving factors. By application of this framework, we assessed the soil services of sediment retention, water yield, and grain production in the Upper-reach Fenhe Watershed. Based on the ecosystem services and human driving factors, the whole watershed was clustered into five groups: 1) municipal area, 2) typical coal mining area, 3) traditional farming area, 4) unsustainable urbanizing area, and 5) ecological conservation area. Management strategies on soils were made according to the clustering based soil services and human activities.

利用汾河上游出口控制站兰村水文站1954—2013年汛期降雨、径流和输沙实测资料,采用线性趋势分析和双累积曲线法分析了汾河上游汛期悬移质输沙变化特征和驱动力对输沙的影响。结果表明,（1）近60年来汾河上游汛期悬移质输沙量和径流量下降显著,且输沙量变化幅度大于径流量。（2）近60年来汾河上游汛期降雨量变化不显著,但降雨量与径流量（P＜0.01）、降雨量和输沙量（P＜0.01）均显著线性相关。（3）近60年来特别是2000年以后汾河上游发生洪水特别是较大洪水的次数显著减少。（4）近60年汾河上游悬移质输沙量的变化大致分为4个阶段,1959年、1981年和2002年是3个转折点。1959年以前主要受降雨和径流的影响;1959—1981年,汾河水库的修建是悬移质输沙量减少的主要驱动力;1981—2002年,降水减少、经济活动和水土保持使得径流量减少,输沙能力减弱;2002年以后,降雨减少特别是暴雨减少,经济活动和水土保持使得径流量和输沙量继续减少,而汾河二库的建设,则使得兰村站悬移质输沙量变为0。

Methylene blue-loaded silica (silica-MB) was coated by a shell of polyethylene glycol (PEG), citrate ions and octacalcium phosphate (OCP) through a facile sol-gel method. The influences of molecular weight of PEG, addition amount of PEG and citric acid on the phase, morphology and chemical composition of samples were characterized by X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. Compared with that of silica-MB, the sustained-release behavior of MB from silica-MB@OCP was sensitive to the shell structure and the pH value of culture solution. At each time interval, the ratio of absorbance of MB monomers over that of MB dimers released from silicaMB@OCP was higher than that from silica-MB, indicating that the significant influence of interaction density among the network of PEG, citrate ions and OCP on the release behavior of MB. Silica-MB and silica-MB@OCP were degraded when MB molecules diffused to the culture solution from solid silica matrix, which would shed light on the self-destruction investigation of drug/drug carrier systems in the biological system. (C) 2015 Elsevier B.V. All rights reserved.

Methylene blue-loaded silica (silica-MB) was coated by octacalcium phosphate (silica-MB@OCP) through a facile sol–gel method. Both MB monomers and dimers were released from silica-MB, while release of MB dimers from silica-MB@OCP was predominant in phosphate-buffered saline and lysosome-like buffer as an indicative of the influence of the molecular weight of polyethylene glycol (PEG) on the interaction density of shell network consisted of PEG, citric acid, ethylenediaminetetraacetic acid and OCP. The ratio evolution of absorbance of dimers over that of monomers was caused by the radical distribution of MB molecules in silica-MB and silica-MB@OCP. The investigation of MB dimers/carrier system would shed light on the investigation of MB dimers in photodynamic therapy for the specific treatment to outgrowing solid tumors with the disproportion between oxygen supply and consumption.

PDF HTML阅读 XML下载 导出引用 引用提醒 西安市城乡建设用地时空扩展及驱动因素 DOI: 10.5846/stxb201306281794 作者: 作者单位: 长安大学,中国科学院生态环境研究中心,山西大学黄土高原研究所,长安大学地球科学与资源学院,长安大学地球科学与资源学院,长安大学地球科学与资源学院 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金(41040011, 41471097);陕西省自然科学基金(2014JM5211); 中央高校基本科研业务费资助项目(自然科学类)(2013G1271098) Spatio-temporal characteristics and & driving forces of built-up land in Xi'an, China Author: Affiliation: The College of Earth and Resources,Changan University,State Key Laboratory of Urban and Regional Ecology, Research Center for Eco–Environmental Sciences ,Chinese Academy of Sciences,,The College of Earth and Resources,Changan University,The College of Earth and Resources,Changan University,The College of Earth and Resources,Changan University Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:城乡建设用地变化及驱动机制是国内外研究的热点领域,我国正处在城镇化快速发展时期,建设用地的迅速扩张已成为当前中国土地利用变化的主要特征。以5期(1975、1990、2000、2005和2010年)土地利用现状数据为基础,利用GIS空间分析技术,提取建设用地变化及空间分布信息,利用建设用地扩展指数和建设用地密度分析方法对近35年来(1975-2010年)西安市建设用地扩展的时空特征进行分析。并结合社会经济数据,对建设用地空间扩展驱动力进行分析。结果表明:西安市建设用地面积急剧增长,建筑密度不断加大,并且城乡空间差异较大。西安市建设用地扩展是多因素综合作用的结果,高程和坡度控制着建设用地的分布格局,城市沿河谷扩展。西安市城市建设应加强区域宏观规划和土地利用详细规划,切实保护秦岭北麓林草地,加强历史文化名城特色,避免低层次文化复古创修。 Abstract:Urban and rural land use change and associated driving mechanisms represent an active field of research in China and abroad. China is experiencing rapid urbanization and expansion of newly constructed land. Specifically, over the last decade, there has been a 78.5% expansion of urban built-up areas, which poses many potential environmental problems. Understanding the processes and driving mechanisms for the expansion of built-up land is conducive to prudent urban planning and management policies. In this study, the Xi'an metropolitan area was approximately divided into the city proper, township region, and rural areas based on various factors such as population size and the percentage of built-up land.We monitored variations in the trajectory of the built-up area and associated driving forces in Xi'an City for the last 35 years by using the Window Analysis Method combined with an expansion index.The results showed that the built-up area in Xi'an increased from 81787.3 hm2 (8.1%) in 1975 to 107171.8 hm2 (10.6%) in 2010. Temporally, the built-up area expanded at an increasing pace. The rate of land change was 173.11 hm2/a from 1975 to 1990 and 1139.39 hm2/a from 1990 to 2010, with the highest expansion rate of 2995.82 hm2/a occurring from 2000 to 2005. Urban and rural spatial differences in land use change were noticeable. Spatially, the central part of the metropolitan area increased more than the surrounding rural area.Built-up land expansion in Xi'an is a complex process subject to multiple factors at various scales. At the macro-scale, geomorphology is a limiting factor for built-up area expansion, i.e., the built-up area was mainly distributed over low terrain initially, followed by the development of tablelands on the higher mountain ranges and the lower river valley. Furthermore, population size and per-capita gross domestic product (GDP) also played significant roles in the pattern of development in the built-up area. At the landscape scale, education facilities, roads and wetlands/parks exerted profound influences on the shape of the built-up land. with Beijing and Shanghai, Xi'an underwent urbanization at a more moderate rate. With a long history of 6000 years and status as the capital city of China for more than 1200 years, Xi'an should not be further developed homogeneously; however, any newly planned construction should give full consideration to the ancient city style and aim to preserve historical relics instead of antique building. Furthermore, urban sprawl should be prohibited in the Qin-ling "forest zone" to the north of the city and the Wei-he River wetlands. Education is a key factor that shapes social and economic structures, with several university towns having become established in this region, in addition to the original southern suburb education agglomeration. To protect high quality farmland, we advise that strict land requisition bans be implemented on cultivated land neighboring the city. It would also be beneficial to improve the efficiency of urban construction projects, strengthen the scientific urban planning process, and avoid excessively encroaching on protected ecological resources. The Guan-zhong Plain, where Xi'an city is located, was the birthplace for Chinese culture. In recent years, the built-up area of this city has spread at a steady rate, which poses serious threats to cultivated land and food security over the long term. Thus, land resources in both urban and rural areas should be managed and configured by coordinating them as a whole. 参考文献 相似文献 引证文献

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