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1.
分形理论是研究复杂巨系统典型形态特征的前沿理论,采用分形理论衍生的聚集维量化模型和形态维量化模型对上海游憩绿地系统进行演化特征的时空分析,基于演化特征和相关规划提出游憩绿地系统布局分形耦合重构的优化方案:8中心5级分形的结构布局优化和大尺度郊野公园的形态布局优化,研究结果表明,测算出的演化特征结果更为符合实际情况,优化方案能进一步促成系统结构形态的分类分级演化、增强系统形态稳定性能、普遍提升服务水平并缩小空间差异,可被有效地用于城乡范畴下的游憩绿地系统规划中。  相似文献   

2.
李玉凤  刘红玉  郑囡  曹晓 《生态学报》2011,31(4):1021-1028
以西溪国家湿地公园为研究案例,从景观功能分类入手,揭示城市湿地公园景观格局与功能特征。结果表明:(1)西溪湿地公园是以生态保护为主,兼顾合理利用为基本功能特征,其生态保护功能区面积占整个公园的53.7%,旅游休闲区面积占46.3%;(2)西溪湿地公园生态保护功能斑块在整个公园中所占面积为42.08%,且面积大、形状复杂、多样性较低;旅游休闲斑块面积占25.41%,并且表现为斑块面积小、形状规则、多样性高等特点;(3)西溪湿地公园生态保护廊道面积是旅游休闲廊道面积的一半左右,其网络结构比旅游休闲廊道复杂,有利于生态保护功能的发挥;(4)生态保护廊道缓冲区内主要由生态保护斑块组成,旅游休闲廊道的缓冲区内生态功能斑块和旅游休闲斑块所占面积相差不大。基于功能分类的景观格局研究方法有利于识别景观功能的空间特征,能够有效揭示景观生态保护与利用的空间关系。  相似文献   

3.
朱从谋  苑韶峰  杨丽霞 《生态学报》2023,43(11):4488-4501
基于主体功能区视角分析国土空间格局演变特征及其生态环境效应可以有效评估规划对国土开发保护的指导作用,为构建合理有序的国土空间格局和保护生态环境提供有益参考。以快速城镇化地区浙江省为例,运用多期土地利用数据,对浙江省主体功能区规划颁布前后两个时期(2000-2010年和2010-2020年)国土空间格局演变进行比较研究,并运用生态环境质量指数和生态贡献率对不同时期生态环境效应进行定量分析。结果表明:(1)与2000-2010年相比,2010-2020年浙江省国土空间转换动态度下降,其空间集聚性减弱,重点开发区的高值集聚(H-H)区域占比由22.3%增加至39.3%。(2)2000-2010年浙江省不同国土空间变化量的增减关系呈现显著的空间负相关性,2010-2020年其空间负相关性减弱,局部空间自相关区域在各主体功能区具有显著空间差异。(3)与2000-2010年相比,2010-2020年浙江省生态环境质量下降速度放缓,生态环境提升区域面积增加,生态环境恶化区域的分布由生态经济区和优化开发区转移至重点开发区。(4)相比于2000-2010年,2010-2020年各主体功能区内农业生产空间与森林生态空间的转换导致生态环境质量改善/恶化的贡献率提升,优化开发区和重点开发区的农业生产向城镇和农村生活空间转换导致生态环境恶化的贡献率下降。  相似文献   

4.
曾瑜皙  钟林生  虞虎  周彬 《生态学报》2022,42(14):5653-5664
已有研究主要从规模角度分析生态系统游憩服务,较少分析其结构。结合生态系统服务理论与旅游体验理论,基于旅游者的生态体验提出生态系统游憩服务功能维度的理论模型,并以三江源国家公园为案例区,采用问卷调查搜集数据,运用因子分析与结构方程模型分析数据、验证假设。研究表明,生态系统游憩服务包括美感体验、游憩机会与适宜环境3个功能维度,其形成受到地形、地表覆被、独特景观、景观格局、植被、保护地空间类型、天气与海拔等要素的影响。在不同区域,由于生态要素条件、旅游者对生态要素与各功能维度的感知和态度存在区别,生态系统游憩服务结构呈现出功能和结构差异性。研究解析了生态系统游憩服务的功能维度,深化了生态系统游憩服务研究,有助于完善生态系统游憩服务理论,优化生态要素管理方式。  相似文献   

5.
刘海龙 《生物信息学》2019,26(11):64-70
美国州立公园与国家公园相比,更强调满足州内居民就近户外休闲游憩需求的功能,这使得其在美国整体公共户外休闲空间体系中占据特殊的位置。在中国第一次全面地研究了美国州立公园体系的发展、特征及与国家公园体系的关系,特别是以部分州为例研究了美国州立公园的分类、质量评估、可达性与空间分布评估等关键问题。研究认为,州立公园的意义在于既缓解了美国国家公园面临的巨大旅游游憩压力,也满足了大众户外休闲游憩的需求。这值得中国在目前构建国家公园与自然保护地体系的同时予以借鉴。最后基于中国的实际需求与挑战,探讨了在省域/区域层次加强构建地方公园、保护地和游憩地体系建设的必要性与途径。  相似文献   

6.
孙才志  闫晓露 《生态学报》2014,34(24):7280-7292
以东北三省开发强度最大的辽河中下游地区—下辽河平原为研究对象,从自然因素和人文因素两个方面,构建下辽河平原景观格局演变的驱动机制指标体系,其中自然驱动力包括气候因素、DEM提取值;人文驱动力主要包括人口状况、经济发展、人民生活水平和科学技术进步四大方面。利用美国地质勘探局(USGS)长时间序列的遥感影像数据,获取了下辽河平原1980—2010年地表景观格局的分布特征,提取下辽河平原近30年来各景观类型的空间分布信息,根据各景观类型面积增长和消退的演变规律,利用Logistic回归模型分析不同时间段下景观格局演变的驱动机制,结果表明:1耕地面积的先增后减,林地、草地面积的先减后增,以及建设用地面积的持续增加是研究区景观格局演变的主要特征;2Logistic回归模型分析的结果表明,不同时期内景观类型变化的驱动因子及其影响力存在一定的差异,但是总体来讲,在中小尺度下,自然驱动因素相对于人文驱动因素的影响较弱,人口、经济发展、城市化水平、技术等因子对于下辽河平原各景观类型的变化具有较强的驱动作用。  相似文献   

7.
基于生态系统服务簇的福州市生态系统服务格局   总被引:2,自引:0,他引:2  
基于InVEST模型、游憩机会谱、因子分析、冷热点分析、SOFM神经网络和地形起伏度等方法,评估福州市6项生态系统服务,分析不同生态系统服务之间的权衡与协同,并阐明区域的主导服务类型和不同地形起伏度下服务簇的空间格局。结果表明: 福州市各项生态系统服务的空间异质性显著,产水、碳固持、生境质量和游憩机会供给总体较高,农产品供给和水土保持相对较弱且高低值差异明显;产水服务与文化服务存在协同关系,调节服务、支持服务与农产品供给服务之间存在权衡关系,权衡与协同高低值呈明显的空间聚集;生态系统服务簇分为郊区游憩簇、水源涵养簇、农产品供给簇、城镇生活簇和森林生态保育簇,不同地形起伏度下的服务簇组成各不相同,具有明显的空间异质性。  相似文献   

8.
杨帆  熊素文  雷婷  赵子羽  刘传虎 《生态学报》2022,42(17):7043-7055
城镇化快速发展背景下,城市自然资源国土空间格局转型引发了流域水生态环境的恶化。基于洞庭湖区岳阳、常德、益阳、荆州4个典型城市及其32个县域数据样本,借助遥感影像交互解译、GIS叠加融合、驱动指标分类提取等数据处理技术,通过土地利用动态度及转移矩阵计算分析城镇化进程中洞庭湖区"三生空间"格局演变的典型特征,并运用灰色关联度模型揭示国土空间格局演变的潜在驱动机制。研究表明:(1)1980-2020年洞庭湖区"三生空间"格局总体分布具有明显的水平地域分异和垂直梯度差异特征,生态空间主要集中在区域中部洞庭湖水域部分及东部、南部、西部的外围林地丘陵区,生产空间主要位于河网冲刷形成的湖滨平原区,生活空间呈点状零散穿插分布于生产、生态空间之中。(2)洞庭湖区各城市"三生空间"时空格局演变随城镇化发展逐渐剧烈,结构变化以城镇建设用地的增加和农业生产用地的缩减最为突出,功能转型体现为城镇生活空间侵蚀农业生产空间,农业生产空间挤占水域生态空间,以及农业生产空间向水域生态空间的回归;各类用地结构与功能转型在县域层面上的阶段差异性与地理协同性亦较为显著。(3)城镇化、工业化及农业现代化作为洞庭湖区"三生空间"格局演变的三大关键驱动力,加速了域内各城市的国土空间格局变化进程,是未来区域战略性生态环境治理及国土空间规划应重视的关键要素。研究内容可为洞庭湖区水网土地资源合理规划提供参考,引导大湖流域生态治理目标下的城镇化高质量发展。  相似文献   

9.
Infectious diseases often spread as spatial epidemic outbreak waves. A number of model studies have shown that such spatial pattern formation can have important consequences for the evolution of pathogens. Here, we show that such spatial patterns can cause cyclic evolutionary dynamics in selection for the length of the infectious period. The necessary reversal in the direction of selection is enabled by a qualitative change in the spatial pattern from epidemic waves to irregular local outbreaks. The spatial patterns are an emergent property of the epidemic system, and they are robust against changes in specific model assumptions. Our results indicate that emergent spatial patterns can act as a rich source for complexity in pathogen evolution.  相似文献   

10.
The mammalian odorant receptor (OR) repertoire is an attractive model to study evolution, because ORs have been subjected to rapid evolution between species, presumably caused by changes of the olfactory system to adapt to the environment. However, functional assessment of ORs in related species remains largely untested. Here we investigated the functional properties of primate and rodent ORs to determine how well evolutionary distance predicts functional characteristics. Using human and mouse ORs with previously identified ligands, we cloned 18 OR orthologs from chimpanzee and rhesus macaque and 17 mouse-rat orthologous pairs that are broadly representative of the OR repertoire. We functionally characterized the in vitro responses of ORs to a wide panel of odors and found similar ligand selectivity but dramatic differences in response magnitude. 87% of human-primate orthologs and 94% of mouse-rat orthologs showed differences in receptor potency (EC50) and/or efficacy (dynamic range) to an individual ligand. Notably dN/dS ratio, an indication of selective pressure during evolution, does not predict functional similarities between orthologs. Additionally, we found that orthologs responded to a common ligand 82% of the time, while human OR paralogs of the same subfamily responded to the common ligand only 33% of the time. Our results suggest that, while OR orthologs tend to show conserved ligand selectivity, their potency and/or efficacy dynamically change during evolution, even in closely related species. These functional changes in orthologs provide a platform for examining how the evolution of ORs can meet species-specific demands.  相似文献   

11.
Classically the oral dentition with teeth regulated into a successional iterative order was thought to have evolved from the superficial skin denticles migrating into the mouth at the stage when jaws evolved. The canonical view is that the initiation of a pattern order for teeth at the mouth margin required development of a sub-epithelial, permanent dental lamina. This provided regulated tooth production in advance of functional need, as exemplified by the Chondrichthyes. It had been assumed that teeth in the Osteichthyes form in this way as in tetrapods. However, this has been shown not to be true for many osteichthyan fish where a dental lamina of this kind does not form, but teeth are regularly patterned and replaced. We question the evolutionary origin of pattern information for the dentition driven by new morphological data on spatial initiation of skin denticles in the catshark. We review recent gene expression data for spatio-temporal order of tooth initiation for Scyliorhinus canicula, selected teleosts in both oral and pharyngeal dentitions, and Neoceratodus forsteri. Although denticles in the chondrichthyan skin appear not to follow a strict pattern order in space and time, tooth replacement in a functional system occurs with precise timing and spatial order. We suggest that the patterning mechanism observed for the oral and pharyngeal dentition is unique to the vertebrate oro-pharynx and independent of the skin system. Therefore, co-option of a successional iterative pattern occurred in evolution not from the skin but from mechanisms existing in the oro-pharynx of now extinct agnathans.  相似文献   

12.
在气候变化和人类活动共同影响下,沙区“生态-经济-社会”复合系统快速变化,为沙漠化治理及区域可持续发展带来了严峻的挑战。因此,揭示沙区“生态-经济-社会”复合系统脆弱性演变规律,辨识影响脆弱性演化的关键因素及区域差异对沙区可持续管理具有重要意义。以内蒙古自治区为研究区,利用“暴露-敏感-适应”评估模型构建沙区“生态-经济-社会”复合系统脆弱性评价指标体系,将空间主成分分析与时空地理加权回归模型相结合,探讨2000—2018年内蒙古“生态-经济-社会”复合系统脆弱性时空演变及关键因素作用机制。结果表明:(1)脆弱性及暴露度、敏感性和适应性三个维度在空间上均有较强的异质性特征,脆弱性具有整体分散、局部聚集的分布格局;暴露度的空间分布为中部高,两边低;敏感性的空间分布为西部高,东部低;适应性的高低值分布与脆弱性相反。(2)脆弱性的变化在总体上呈现大部分区域降低,局部区域升高的趋势,显著升高区域主要聚集在内蒙古南部地区。(3)影响脆弱性分布的因素在每年均有所不同,但总体上植被覆盖度、沙漠化程度、气象指数等生态指标是影响脆弱性显著变化区域的主要因素。  相似文献   

13.
Abstract. The species composition and morphological and functional traits of ecological systems are compared. The significance of the resulting relationship is interpreted considering the underlying spatial environmental variation. Using 60 morphological and functional traits, a gradient of ecological persistence was detected in Mediterranean grasslands along an altitudinal range of ca. 1200 m. This pattern coincides with the one expressed by its taxonomic composition and thus permits ‘styles of adaptation’ of ecological systems to be recognized. Species composition may represent one of the possible combinations which optimises its environmental fit. The relevance to ecological theory of this pattern of grassland organization is discussed in the context of a hypothetical model of evolution.  相似文献   

14.
邴振华  高峻 《生态学报》2016,36(14):4298-4306
九寨沟作为国家级自然保护区、风景名胜区和世界自然遗产地,面临在有效保护自然资源的同时最大化地满足人类游憩服务需求的挑战。学者已经采用CVM、TCM等不同方法的测算九寨沟游憩价值,并针对测算结果的有效性和信度进行探讨,但以往的研究方法无法测算不同旅游资源的游憩价值贡献。以景观服务为视角,通过景观游憩服务识别的方法,进行不同旅游资源价值评估。同类旅游资源因位置不同、个人偏好不同也会产生不同的价值贡献,以参与式制图的方法进行不同游憩服务点的感知评价,实现游憩价值的空间分异研究。采用参与式制图与条件价值法(CVM)相结合的方法,实现游客对游憩服务点的感知评价和位置制图,并完成游客对游憩服务的支付意愿调研,实现价值空间分异研究,共调研730人,有效样本614。分析发现,2012年九寨沟游憩支付意愿率为72.95%,取旅游者意愿支付平均值354.98元,测算九寨沟自然保护区2012年的游憩价值为9.4亿元,其中价值最高是高山湖泊、瀑布、滩流等观赏水体,为2.9亿元,最低的是观赏植物,为0.47亿元。从空间位置来看,单位价值高的游憩服务点主要集中在几条沟谷两侧,特别是已开发的树正沟、日则沟和则查洼沟。游憩价值的空间分异研究注重不同位置旅游资源价值贡献的强弱对比,以期为九寨沟自然保护区的具体监控管理提供依据。  相似文献   

15.
Comparative studies of hominids have long sought to identify mutational events that shaped the evolution of the human nervous system. However, functional genetic differences are outnumbered by millions of nearly neutral mutations, and the developmental mechanisms underlying human nervous system specializations are difficult to model and incompletely understood. Candidate-gene studies have attempted to map select human-specific genetic differences to neurodevelopmental functions, but it remains unclear how to contextualize the relative effects of genes that are investigated independently. Considering these limitations, we discuss scalable approaches for probing the functional contributions of human-specific genetic differences. We propose that a systems-level view will enable a more quantitative and integrative understanding of the genetic, molecular and cellular underpinnings of human nervous system evolution.  相似文献   

16.
贵州典型坝子土地利用强度空间演变及景观格局响应   总被引:1,自引:0,他引:1  
刘亚香  李阳兵  易兴松  程星 《生态学杂志》2017,28(11):3691-3702
基于坝子(喀斯特山区受人类活动影响最明显的特殊地貌)尺度较小的特征,运用系统网格法,结合半方差变异函数修正模型,分析贵州省境内3种类型共15个坝子2005、2010、2015年土地利用强度的空间演变特征,揭示贵州岩溶山区典型坝子土地利用强度空间演变的一般规律及其与坝子内部景观格局变化的相互关系.结果表明: 贵州坝子土地利用强度空间动态演变和景观格局响应模式展现出明显的类型差异.总体上,土地利用强度随坝子经济水平由高到低呈梯度递减.微观演变上,市县中心坝子的土地利用强度围绕坝地中心外围呈同心带状先减后增,空间演变趋势为稳定-扩张型;市县周围坝子的土地利用强度以单一“极-轴”为高强度中心,变化兼具增减,演变趋势为波动型;偏远地区坝子的土地利用强度基本稳定不变,甚至小幅减弱,演变趋势为稳定-衰弱型;坝子景观格局与土地利用强度变化因坝区主导功能差异存在5种不同的响应关系模式.研究期间,3种类型坝子土地利用强度的空间演变受自然和人文因子双重控制,各因子之间相互作用形成其空间演变的典型特征.  相似文献   

17.
Abstract The importance of the spatial pattern of vegetation for hydrological behavior in semiarid environments is widely acknowledged. However, there is little empirical work testing the hypothetical covariation between vegetation spatial structure and hillslope water and sediment fluxes. We evaluated the relationships between vegetation structural attributes (spatial pattern, functional diversity), soil surface properties (crust, stone, plant, and ground cover, and particle size distribution) and hillslope hydrologic functioning in a semiarid Mediterranean landscape; in particular, we tested whether decreasing patch density or coarsening plant spatial pattern would increase runoff and sediment yield at the hillslope scale. Runoff and sediment yield were measured over a 45-month period on nine 8 × 2-m plots that varied in vegetation type and spatial pattern. We grouped vegetation into functional types and derived plant spatial pattern attributes from field plot maps processed through a GIS system. We found that there was an inverse relationship between patch density and runoff, and that both runoff and sediment yields increased as the spatial pattern of vegetation coarsened. Vegetation pattern attributes and plant functional diversity were better related to runoff and sediment yield than soil surface properties. However, a significant relationship was found between physical crust cover and plant spatial pattern. Our results present empirical evidence for the direct relationship between the hydrologic functioning of semiarid lands and both the spatial pattern and the functional diversity of perennial vegetation, and suggest that plant spatial pattern, physical crust cover, and functional diversity may be linked through feedback mechanisms.  相似文献   

18.
This paper is about a general methodology for pattern transformation. Patterns are network representations of the relations among structures and functions within an organism. Transformation refers to any realistic or abstract transformation relevant to biology, e.g. ontogeny, evolution and phenotypic clines. The main aim of the paper is a methodology for analyzing the range of effects on a pattern due to perturbing one or more of its structures and/or functions (transformation morphology). Concepts relevant to such an analysis of pattern transformation are reviewed and several new ones introduced: pattern unit; direct and indirect functional demands; compatibility and trade-off; integrating, adding and decoupling; functional effectiveness; spatial, profile and other architectonic constraints; domains of structure-function relations; goal and process adaptability; multiple pathways. The paper is written from the the perspective of architectonic morphology, viz. functional morphology focusing on the relation between anatomical coherence and the compatibility of functions. The advantages and disadvantages of inductive and deductive approaches are discussed.  相似文献   

19.
矿区生态风险评价研究述评   总被引:7,自引:3,他引:4  
潘雅婧  王仰麟  彭建  韩忆楠 《生态学报》2012,32(20):6566-6574
作为世界上矿产资源最丰富的国家之一,我国的矿山开采活动在给经济发展注入强大拉动力的同时,也给矿区生态环境带来了巨大的生态风险。总结前人相关研究,在对比分析了矿区生态风险及其评价与区域生态风险评价异同的基础上,初步明晰矿区生态风险具有风险源的多样性、空间影响边界的模糊性、随空间距离的衰减性及时间累积的延续性等特性。目前矿区生态风险评价的矿区类型过多集中于金属矿区的重金属污染等单项风险,对综合生态风险评价的重视不充分,多基于景观格局、生态环境问题视角,结果多对斑块或生态系统风险评价进行拼接,欠缺基于空间异质性的整体综合;风险度量模型、指标体系法和空间分析法则是较为常用的矿区生态风险评价方法,但在模型模拟方面略显不足。基于现有研究进展,预期矿区独特性的体现、空间格局的关注、"3S"技术的综合应用、生态安全阈值的设定、不确定性表征、基于评价结果的风险规避等将有望成为未来研究的重点。  相似文献   

20.
Non-random mortality associated with commercial and recreational fisheries have the potential to cause evolutionary changes in fish populations. Inland recreational fisheries offer unique opportunities for the study of fisheries induced evolution due to the ability to replicate study systems, limited gene flow among populations, and the existence of unexploited reference populations. Experimental research has demonstrated that angling vulnerability is heritable in Largemouth Bass Micropterus salmoides, and is correlated with elevated resting metabolic rates (RMR) and higher fitness. However, whether such differences are present in wild populations is unclear. This study sought to quantify differences in RMR among replicated exploited and unexploited populations of Largemouth Bass. We collected age-0 Largemouth Bass from two Connecticut drinking water reservoirs unexploited by anglers for almost a century, and two exploited lakes, then transported and reared them in the same pond. Field RMR of individuals from each population was quantified using intermittent-flow respirometry. Individuals from unexploited reservoirs had a significantly higher mean RMR (6%) than individuals from exploited populations. These findings are consistent with expectations derived from artificial selection by angling on Largemouth Bass, suggesting that recreational angling may act as an evolutionary force influencing the metabolic rates of fishes in the wild. Reduced RMR as a result of fisheries induced evolution may have ecosystem level effects on energy demand, and be common in exploited recreational populations globally.  相似文献   

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