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21.
近年来,我国雨洪灾害频发,给人民生命财产造成了重大损失,反映出我国部分城市仍存在雨洪韧性能力不足的问题。荷兰是世界上海拔最低的国家,在应对气候变化和雨洪风险方面取得了很好的成绩,逐渐形成了富有韧性的水治理新范式。研究介绍了荷兰水治理概况、若干典型水治理项目、水治理行政框架、水治理法规体系等,剖析了荷兰治水理念的不断深化过程,总结了荷兰在水治理方面的主要经验,即坚持更长更广更深的水治理策略、 “国家、省、市”三级协同治理、水利工程和空间规划紧密结合、多层级雨洪风险防控体系、提供更多的韧性空间、水治理和国土空间规划体系从深度合作向一体化转变。借鉴荷兰经验并结合我国国土空间规划实际情况,研究尝试提出坚持底线思维、问题导向、顺应跨尺度的水文自然过程、提升蓝绿网络的连通性、将灰色基础设施改造提升与基于自然的解决方案(Natural -based Solution)相结合、扩大承水缓冲空间、提高有效救灾能力、构建水治理顶层制度框架、将雨洪韧性理念全面融入到各级空间规划体系九点战略思考,旨在为我国雨洪韧性空间规划提供参考。 相似文献
22.
城市公园作为城市生态空间的主要类型之一,在维持、增加和提升城市生态系统服务中发挥着重要作用。人们对高质量生活的追求驱动着生态系统服务需求的演进,生态系统文化服务也日益受到关注。然而,对城市公园生态系统文化服务的空间格局特征及其影响因素的研究还显薄弱。以杭州市主城区239个城市公园作为研究对象,以微博数据测算生态系统文化服务,利用逐步多元线性回归和地理加权回归模型分析公园生态系统文化服务空间格局特征和影响因素的空间异质性。结果表明：（1）杭州主城区城市公园的生态系统文化服务空间分布差异性明显,生态系统文化服务小于0.44的公园,集中在拱墅区、西湖区和上城区,成条带状聚集;生态系统文化服务在0.45—0.54的公园,其空间分布呈现双核心聚集;生态系统文化服务大于0.55的公园,呈现多核心聚集分布特征,并且分布最广,涉及的公园最多。（2）逐步多元回归分析表明城市公园面积、NDVI（归一化植被指数）、公园水景观、路网密度、丰富度指数和聚集度指数是公园生态系统文化服务的主要影响因素,其中NDVI、城市公园面积、公园水景观、斑块丰富度指数和聚集度指数对生态系统文化服务有显著正影响,路网密度对生态系统文化服务有显著负影响。（3）地理加权回归分析表明不同影响因素对公园生态系统文化服务呈现出不同的正负影响效应,具有明显的空间异质性;城市公园面积、NDVI、公园水景观和斑块丰富度指数对公园生态系统文化服务具有显著正向影响,公园水面积占比、路网密度和公园PM2.5浓度对公园生态系统文化服务具有显著负向影响,人口密度、不透水面积占比、斑块数量和蔓延度指数对公园生态系统文化服务具有正负两种影响。对公园生态系统文化服务影响强度从高到低依次是公园路网密度、人口密度、NDVI、不透水面积占比、公园水景观、斑块丰富度指数、城市公园面积、斑块数量、公园PM2.5浓度、蔓延度指数和公园水面积占比。 相似文献
23.
Dan Zhu;Yilong Wang;Philippe Ciais;Frédéric Chevallier;Shushi Peng;Yao Zhang;Xuhui Wang; 《Global Change Biology》2024,30(1):e17043
In the northern high latitudes, warmer spring temperatures generally lead to earlier leaf onsets, higher vegetation production, and enhanced spring carbon uptake. Yet, whether this positive linkage has diminished under climate change remains debated. Here, we used atmospheric CO2 measurements at Barrow (Alaska) during 1979–2020 to investigate the strength of temperature dependence of spring carbon uptake reflected by two indicators, spring zero-crossing date (SZC) and CO2 drawdown (SCC). We found a fall and rise in the interannual correlation of temperature with SZC and SCC (RSZC-T and RSCC-T), showing a recent reversal of the previously reported weakening trend of RSZC-T and RSCC-T. We used a terrestrial biosphere model coupled with an atmospheric transport model to reproduce this fall and rise phenomenon and conducted factorial simulations to explore its potential causes. We found that a strong–weak–strong spatial synchrony of spring temperature anomalies per se has contributed to the fall and rise trend in RSZC-T and RSCC-T, despite an overall unbroken temperature control on net ecosystem CO2 fluxes at local scale. Our results provide an alternative explanation for the apparent drop of RSZC-T and RSCC-T during the late 1990s and 2000s, and suggest a continued positive linkage between spring carbon uptake and temperature during the past four decades. We thus caution the interpretation of apparent climate sensitivities of carbon cycle retrieved from spatially aggregated signals. 相似文献
24.
Baptiste J. Wijas;Mike Letnic;William K. Cornwell; 《Austral ecology》2024,49(7):e13555
Drylands are characterized by high spatial variability in resource availability due to sporadic rainfall, topography of the landscape and important effects of animals. Resource availability gradients may trigger patterns in decomposer population abundances and activity, which could affect ecosystem functions such as decomposition. Here, we examined the influence of resource availability gradients on the importance of termites in the decomposition of wood and grass litter. We placed wood blocks and grass litter baits in bags accessible and inaccessible to termites across wood and grass resource gradients as determined by the presence or absence of a top mammalian predator and across topographic gradients during a 9-month period in arid Australia. We hypothesized that grass-eating termite activity would track grass abundance and wood-eating termite activity would track wood abundance. Termites were the predominant decomposition agent at these sites. Termites contributed to 99.5% of wood decomposition and 83.9% of grass decomposition during our study period. For wood, the termite effect was spatially variable and increased with habitat wood availability, which was greatest on dunes and where top predators were absent. However, the contribution of termites to grass litter decomposition did not track grass availability or termite abundance. The highest effects of termites on grass decomposition rates were found in habitats where the absence of top predators led to low grass availability. Our findings highlight how spatial variability in resources in addition to other factors that we do not document but are known to be influenced by the presence of top predators, such as insectivore predation rates, across the landscape could affect ecosystem functions such as decomposition. 相似文献
25.
Biao Zhang;Kai Xue;Wenjing Liu;Shutong Zhou;Shipeng Nie;Yichao Rui;Li Tang;Zhe Pang;Linfeng Li;Junfu Dong;Cong Xu;Lili Jiang;Shaopeng Wang;Yanbin Hao;Xiaoyong Cui;Yanfen Wang; 《Global Ecology and Biogeography》2024,33(5):e13825
Species–area relationships (SAR) are widely utilized for estimating the species richness and its spatial turnover across various scales. Despite the prevalent characterization of SAR using the power law in many microbial community studies, its efficacy remains unvalidated. This study aims to characterize the microbial SAR and its mechanisms in alpine grassland soils on the Qinghai-Tibet Plateau (QTP). 相似文献
26.
Francesco Santi;Riccardo Testolin;Piero Zannini;Michele Di Musciano;Virginia Micci;Lorenzo Ricci;Riccardo Guarino;Gianluigi Bacchetta;José María Fernández-Palacios;Mauro Fois;Konstantinos Kougioumoutzis;Kadir Boğaç Kunt;Federico Lucchi;Frédéric Médail;Toni Nikolić;Rüdiger Otto;Salvatore Pasta;Maria Panitsa;Konstantinos Proios;Spyros Sfenthourakis;Stylianos M. Simaiakis;Claudio A. Tranne;Kostas A. Triantis;Alessandro Chiarucci; 《Global Ecology and Biogeography》2024,33(8):e13855
The intrinsic characteristics of islands make them a unique study system for the investigation of ecological and evolutionary dynamics. The Mediterranean Basin, an island-rich biodiversity hotspot, still lacks a comprehensive spatial database for these geographic features. This study presents the first comprehensive spatial database of all Mediterranean islands larger than 0.01 km2, aiding ecological investigations and interdisciplinary research. 相似文献
27.
Sarah F. Brosnan; 《Ethology : formerly Zeitschrift fur Tierpsychologie》2024,130(4):e13433
Reciprocally patterned behavior is widespread in animals in the wild, but experimental evidence has been frustratingly inconsistent. Contrary to earlier contentions that this inconsistency is because reciprocity in non-human species is a rare or fragile effect, recent authors have argued that the evidence suggests that reciprocity is widespread, that it often relies on cognitive mechanisms that are common across species, and is potentially an important factor in animals' daily lives. Another possible explanation for its apparent rarity, then, is that due to experimental studies' (intentionally) structured environment, they can lack the appropriate context to promote and support reciprocity. Focusing on outcomes from experimental reciprocal tasks in non-human primates, I consider several factors that may be important, including the identity of the interactors and their relationship to one another, whether there is free choice of partners, whether the individuals are interacting directly, the timing of the interaction, the commodity involved, whether individuals have a reason to reciprocate, and the equity of the interaction. Clarifying the role of each of these factors will help improve experimental tasks and the social and ecological contexts that promote reciprocity. 相似文献
28.
Raelene M. Crandall;Yingen M. Chew;Jennifer M. Fill;Jesse K. Kreye;J. Morgan Varner;Leda N. Kobziar; 《Ecology and evolution》2024,14(7):e70021
Overstory trees serve multiple functions in grassy savannas. Past research has shown that understory species can vary along gradients of canopy cover and basal area in savannas. This variation is frequently associated with light availability but could also be related to other mechanisms, such as heterogeneity in soil and litter depth and fire intensity. Several savanna studies have found differences in understory plant functional groups within the local environment near trees versus away from them in canopy openings. Although small-scale variation is known to be high in southeastern U.S. pine savannas, patterns in understory species diversity have not been examined at the scale of individual overstory pine trees in this system. We conducted an observational study of the relationship between understory plant communities and proximity to individual pine trees in xeric and mesic pine savannas in frequently burned sites (1–3 year intervals). We recorded the plant community composition in plots adjacent to tree boles (basal) or outside crown driplines (open). Within each environment, raw species richness was significantly greater in open locations, where light transmittance was greater. In contrast, rarified species richness did not differ. Multivariate analyses showed that community composition differed significantly between basal and open plots. One native, woody species in each environment, Serenoa repens (W. Bartram) Small in mesic and Diospyros virginiana L. in xeric, was more abundant in basal plots. In mesic environments, eight species had greater occurrence in open plots. In xeric environments, four understory forbs were more abundant in open plots. Our results support previous research indicating that individual pine trees are associated with significant variation in understory vegetation in pine savannas. 相似文献
29.
联合国《生物多样性公约》第十五次缔约方大会(COP15)提出“30×30”目标, 呼吁到2030年保护全球30%的陆地和海洋面积。目前自然保护地覆盖率不足、拓展空间有限、与其他土地类型兼容性有限, 实现生物多样性全面有效保护的目标不能仅仅依靠自然保护地。然而, 国际上提倡的“其他基于区域的有效保护措施” (other effective area-based conservation measures, OECMs)尚存较多局限, 与我国实际情况的适配性不足, 难以直接指导我国自然保护地体系外就地保护实践。中国需要尽快建立一套与当前自然保护地相互补充的、符合中国国情的就地保护体系。基于此, 本研究提出“自然保护兼用地” (conservation compatible land, CCL)的概念——“由各类主体申请、各级政府依法确认, 以保护和利用相兼容的管理方式, 对高生物多样性地区进行长期、有效保护的陆域或水域”, 作为我国自然保护地外的就地保护措施。本研究对CCL的内涵、定位、特征进行初步界定, 并从法律政策和管理实践方面论述其可行性。未来我国的国土空间布局应包含自然保护专用地(自然保护地和生态保护红线)、CCL (兼有生物多样性保护以及农林渔牧、文化、生活等其他使用功能)以及可持续利用地(其他生产与生活用地)三大类。CCL有助于整合我国现有的自然保护地体系外的保护措施, 全面系统认识自然保护地外的就地保护措施的作用, 梳理经验、推广实践、整合资源、扩大影响。未来可进一步形成多层次、多梯度、保护与利用统筹协调的全域土地利用空间格局, 使每一寸中国国土都兼顾保护与发展功能。本研究旨在为中国自然保护地外的就地保护实践提供理论依据, 并为全球“30×30”生物多样性保护目标贡献中国智慧与中国方案。 相似文献
30.
Mahtab Yazdanian Tuomas Kankaanpää Juhani Itämies Reima Leinonen Thomas Merckx Juha Pöyry Pasi Sihvonen Anna Suuronen Panu Välimäki Sami M. Kivelä 《Insect Conservation and Diversity》2023,16(5):600-615
- Dramatic insect declines, and their consequences for ecosystems globally, have received considerable attention recently. Yet, it is still poorly known if ecological and life-history traits can explain declines and whether insect decline occurs also at high latitudes. Insects' diversity and abundance are dramatically lower at high latitudes compared to the tropics, and insects might benefit from climate warming in high-latitude environments.
- We adopted a trait- and biomass-based approach to estimate temporal change between 1993 and 2019 in Finnish macro-moth communities by using data from 85 long-running light traps. We analysed spatio-temporal variation in biomass of moth functional groups with Joint Dynamic Species Distribution Models while accounting for environmental variables.
- We did not detect any declining trends in total moth biomass of moth functional groups, and most groups were stable over time. Moreover, biomass increased for species using coniferous trees, lichens, or mushrooms as hosts, multivoltine species, as well as monophagous and oligophagous species feeding on trees. We found that length and temperature of the growing season, winter climatic conditions, and habitat structure all partially explained variation in moth biomass.
- Although boreal moth communities are rapidly changing due to species turnover, in terms of total biomass they seem to contradict the trend of dramatic insect declines observed globally. This may lessen the immediate possibility of negative bottom-up trophic cascades in boreal food webs.