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1.
The robber crab (Birgus latro), also known as the coconut crab, is the world's largest land-living arthropod, with a weight reaching 4 kg and a length of over half a meter [1]. Apart from the marine larval stage 2, 3, this crab is fully terrestrial, and will actually drown if submerged in water [4]. A transition from sea to land raises dramatically new demands on the sensory equipment of an animal. In olfaction, the stimulus changes from hydrophilic molecules in aqueous solution to mainly hydrophobic in the gaseous phase [5]. The olfactory system of land crabs thus represents an excellent opportunity for investigating the effects of the transition from sea to land. Have land crabs come to the same solutions as other terrestrial animals, or is their olfactory sense characterized by unique innovations? Here, we show that the robber crab has evolved an olfactory sense with a high degree of resemblance to the insect system. The similarities extend to physiological, behavioral, and morphological characters. The insect nose of the robber crab is a striking example of convergent evolution and nicely illustrates how similar selection pressures result in similar adaptation  相似文献   

2.
研究高程-坡度-岩性组合形成的不同土地类型的土壤侵蚀时空演变有重要意义。选取大宁河流域和梅溪河流域,以1988年、2000年、2010年和2015年4期遥感影像为数据源,借助RS和GIS技术,通过计算土壤侵蚀强度综合指数和冷热点分析,探讨不同土地类型的土壤侵蚀分布及演变规律,揭示其现实与理论意义。结果表明:(1)流域土壤侵蚀正在发生转型,即两流域各土地类型的土壤侵蚀强度指数随着时间的变化而逐渐降低,土壤侵蚀量由增到减,土壤侵蚀状况呈现好转趋势;(2)就两流域土壤侵蚀空间数量变化而言,土壤侵蚀演变热点区多为中山陡坡石灰岩区,且大宁河流域土壤侵蚀状况优于梅溪河流域;(3)两流域土壤侵蚀演变主要分布于中山陡坡石灰岩和砂岩区,在坡度和岩性上具有相似性,在海拔上具有差异性;在同一土壤侵蚀强度下,两流域不同土地类型土壤侵蚀演变具有一定的相似性;(4)土地类型影响土壤侵蚀分布,探究人类活动下不同土地类型与土壤侵蚀响应耦合关系将是下一步研究的方向。  相似文献   

3.
The role of axial form and function during the vertebrate water to land transition is poorly understood, in part because patterns of axial movement lack morphological correlates. The few studies available from elongate, semi-aquatic vertebrates suggest that moving on land may be powered simply from modifications of generalized swimming axial motor patterns and kinematics. Lungfish are an ideal group to study the role of axial function in terrestrial locomotion as they are the sister taxon to tetrapods and regularly move on land. Here we use electromyography and high-speed video to test whether lungfish moving on land use axial muscles similar to undulatory swimming or demonstrate novelty. We compared terrestrial lungfish data to data from lungfish swimming in different viscosities as well as to salamander locomotion. The terrestrial locomotion of lungfish involved substantial activity in the trunk muscles but almost no tail activity. Unlike other elongate vertebrates, lungfish moved on land with a standing wave pattern of axial muscle activity that closely resembled the pattern observed in terrestrially locomoting salamanders. The similarity in axial motor pattern in salamanders and lungfish suggests that some aspects of neuromuscular control for the axial movements involved in terrestrial locomotion were present before derived appendicular structures.  相似文献   

4.
5.
Indigenous woody species are important natural resources in West African savannas. Information about their population structures and response to human impact, particularly land use, however, is scarce. In this study, we explored (1) the effect of land use on the population structure of woody savanna species; and (2) searched for species with similar population structures related to comparable ecological preferences. Using generalized linear models, we separately analyzed the size‐class distribution (SCD) of 30 species to reveal the influence of three land cover types (non‐arable land, fallows, and protected areas) on population structures. Generalized linear models were applied to identify comparable population structures of species with similar ecological preferences. We were able to identify five groups for shrub species and four groups for tree species with different population structures and comparable ecological preferences. In terms of human impact, we detected four groups of species responding similarly to land use. Especially for trees, we found a strong influence of local land use on SCD and hence, population structures. The SCD of shrub species tends to be more related to species' ecological preferences. Some of the shrub species may be characterized as ubiquitous species as their SCD is neither related to land use nor ecological preferences, indicating a high tolerance to disturbance. The observed results have implications on local woody species composition in relation to land use. According to this, we propose focusing on trees when developing appropriate local land use management strategies.  相似文献   

6.
基于CA-Markov模型的石羊河流域生态承载力时空格局预测   总被引:5,自引:0,他引:5  
生态承载力是区域可持续发展的重要物质基础。为了探讨我国干旱区内陆河流域未来生态承载力的时空格局变化,以石羊河流域为研究区,基于该流域1992、2002年和2012年3期Landsat TM遥感影像,选取10个影响生态承载力变化的主要驱动因素,利用元胞自动机-马尔科夫模型(CA-Markov),以土地利用预测为切入点,对该流域2022年的生态承载力时空格局进行了模拟预测。首先基于1992—2002年数据预测了2012年石羊河流域土地利用状况,并与当年实际土地利用状况进行对比和验证,结果显示:Kappa系数为0.7956,说明本文所选用的预测方法预测结果可靠,可以用于该流域土地利用预测;其次,以2012年为起始年,模拟预测了2022年土地利用空间数据,并计算生态承载力时空格局,结果显示:2022年石羊河流域单位面积生态承载力与1992年、2002年和2012年相比整体空间分布格局变化不大,但区域内部变化却呈明显的空间分异特征;1992—2022年流域生态承载力总量以2002年为拐点呈先减少后增加的趋势,其中建设用地的生态承载力增加最为显著;预测可知,较2012年,2022年流域上游山区的林地、中游绿洲的建筑用地生态承载力均增加较快,且呈现较明显的斑块聚集,而中、下游绿洲区耕地、草地生态承载力增、减变化复杂,斑块分布较为离散和破碎;2012—2022年土地利用类型将发生频繁转换,导致流域生态承载力结构组成变化较大,其中未利用地的转出对2022年流域生态承载力的增加贡献突出。研究结果表明自2002年以后,该流域实施的退耕还林还草、关井压田等生态工程已经并将继续对该流域生态效益的提高起到积极的作用。  相似文献   

7.
Tropical montane cloud forest landscapes are changing, and forest conversion to other land uses is a major driver of biodiversity loss. Land use intensification can lead to significant losses in biodiversity and carbon storage (C); however, the impacts may vary greatly depending on land use type, management practices, and environmental context. We investigated how biodiversity and C are related along a gradient of land use intensification characterized by four dominant land uses in the upper part of Antigua River watershed, Mexico. The land uses were montane cloud forest, secondary forest, and traditional and intensive shade coffee plantations. We determined tree species composition, diversity, ecosystem structure, wood density and C content in dominant tree species to assess aboveground biomass (AGB) and C storage within eight study sites across the land use intensity gradient. A total of 83 tree species was recorded. A canonical correspondence analysis indicated that land uses are separated by particular tree species assemblages. Forests had higher basal area, density, and biomass than coffee plantations, however, the traditional shade coffee plantation had values similar to secondary forest. Calculating C using the standard estimate of 50% of AGB resulted in an overestimation of stored C by 5.8 to 4.1% compared to calculations based on actual measurements. Carbon storage in AGB and biodiversity were strongly and positively related across the land use intensity gradient, although the distinction between the two different intensities of coffee plantation management was not consistently as clear as we had expected. Carbon was highest in forest, but secondary forests and traditional shade coffee plantation had similar C, while intensive coffee had the lowest C content. These results highlight the importance of considering the potential of low intensity land uses such as traditional coffee plantations to mitigate biodiversity loss and preserve ecosystem functions as part of conservation efforts.  相似文献   

8.
Cetaceans (whales, dolphins, and porpoises) are an order of mammals that originated about 50 million years ago in the Eocene epoch. Even though all modern cetaceans are obligate aquatic mammals, early cetaceans were amphibious, and their ancestors were terrestrial artiodactyls, similar to small deer. The transition from land to water is documented by a series of intermediate fossils, many of which are known from India and Pakistan. We review raoellid artiodactyls, as well as the earliest families of cetaceans: pakicetids, ambulocetids, remingtonocetids, protocetids, and basilosaurids. We focus on the evolution of cetacean organ systems, as these document the transition from land to water in detail.  相似文献   

9.
Biological invasions and land‐use changes are two major causes of the global modifications of biodiversity. Habitat suitability models are the tools of choice to predict potential distributions of invasive species. Although land‐use is a key driver of alien species invasions, it is often assumed that land‐use is constant in time. Here we combine historical and present day information, to evaluate whether land‐use changes could explain the dynamic of invasion of the American bullfrog Rana catesbeiana (=Lithobathes catesbeianus) in Northern Italy, from the 1950s to present‐day. We used maxent to build habitat suitability models, on the basis of past (1960s, 1980s) and present‐day data on land‐uses and species distribution. For example, we used models built using the 1960s data to predict distribution in the 1980s, and so on. Furthermore, we used land‐use scenarios to project suitability in the future. Habitat suitability models predicted well the spread of bullfrogs in the subsequent temporal step. Models considering land‐use changes predicted invasion dynamics better than models assuming constant land‐use over the last 50 years. Scenarios of future land‐use suggest that suitability will remain similar in the next years. Habitat suitability models can help to understand and predict the dynamics of invasions; however, land‐use is not constant in time: land‐use modifications can strongly affect invasions; furthermore, both land management and the suitability of a given land‐use class may vary in time. An integration of land‐use changes in studies of biological invasions can help to improve management strategies.  相似文献   

10.
In the present study some qualitative and quantitative features of the reticular formation of the medulla oblongata, pons and midbrain have been elucidated by cytoarchitectonic methods in the dolphin (Tursiops truncatus). The studies have demonstrated that similar to land mammalia, the dolphin has a reticular formation made up of spatially open cell groups lying in the deepest parts of the brain stem. Cytoarchitectonically the component parts of the reticular formation show a number of peculiarities enabling us to distinguish separate nuclei. In the dolphin peculiar architectonics have been observed in the nucleus gigantocellularis medullae oblongatae, nucleus papillioformis or the nucleus reticularis tegmenti Bechterewi and the nucleus centralis superior medialis seu ventralis. Fairly poor in cells are the nucleus centralis caudalis pontis and the nucleus centralis oralis pontis. We failed to single out as autonomous nuclei cell groups corresponding to the nucleus funiculi lateralis and the nucleus paratrochlearis of the land mammalia. The size and density of cells in nuclei have a number of peculiarities. The analysis of the ratios of the brainstem volume to that of reticular structures has shown them to be the smallest in the dolphin as compared with land mammals. The smaller share held by the brain-stem reticular formation and its cytoarchitectonic features can be associated with the functional properties resulting from the greater specialization of some of brain-stem systems (e.g. auditory, vestibular, extrapyramidal etc.) in the dolphin in comparison with land mammals.  相似文献   

11.
Land use intensification in forests is a main driver of global biodiversity loss. Although historical state of land use differs between subtropical and temperate zones, gradients of land-use intensities similarly range from unmanaged to very intensively managed forests. Irrespective of similar land use forces in both climate zones, comparative studies on land use effects are still rare. Such studies are, however, promising in discovering more general impacts and geographical specifics of land use intensification. We studied litter-dwelling invertebrates along a gradient of increasing land use intensity in subtropical forests in Southern Brazil and temperate forests in Central Europe using similar sampling designs. Effects of land use intensity on the entire community were analyzed on the level of orders and feeding guilds. In both climate zones a similar number of individuals were caught when standardizes to 100 pitfall trap days, but taxa richness was higher in the subtropics. Moreover, community composition differed between both climate zones. In both regions, land use intensity did not affect taxa richness, but invertebrate abundance was affected in opposite ways; while increasing land use intensity resulted in a decrease of invertebrate abundance in the subtropics, an increase was observed in the temperate zone and this was mostly consistent regarding different feeding guilds. Management practices should take into account that the effect of land use intensity on biodiversity can differ drastically among climatic regions.  相似文献   

12.
石飞  杨庆媛  王成  江娟丽  胡蓉 《生态学报》2021,41(14):5747-5763
区域耕地休耕规模测算是耕地休耕空间配置的重要组成部分,从资源承载力视角理解,其本质是将休耕空间布局于耕地资源承载力相对较低的区域。立足于从区域耕地生态经济系统探索耕地休耕规模,运用能值分析方法和生态足迹方法,以生态严重退化地区、国家第一批休耕试点县的贵州省松桃县为案例区,修正了耕地能值生态足迹改进模型(ECEF,简称"修正模型")与耕地能值可持续指数(ESIcl),测算了松桃县2016年休耕面积范围值。结果表明:(1)耕地能值生态盈亏可以作为乡镇是否应该休耕的判定标准,基于此测算的最大休耕面积关键在于测算生态耕地面积。总体来看,全县耕地能值生态赤字,应该安排耕地休耕;从分乡镇来看,有3个乡镇可以不休耕、25个乡镇应该休耕。按照全县平均统计(SCAL)和按照分乡镇统计(STL),全县最大休耕面积分别19558.62hm2和17673.83hm2。最大休耕面积中等及以上等级的乡镇散布于4个区域的8个乡镇。(2)ESIcl可以作为休耕乡镇时序的判定标准,其优先休耕乡镇的最大休耕面积之和即为全县最小休耕面积。全县ESIcl偏低,应该适度休耕。优先休耕、适度休耕和暂不休耕的乡镇分别有2个、23个和3个。全县最小休耕面积1396.10hm2,占耕地面积的1.88%。按照全县平均统计(SCAL),全县休耕面积范围值1396.10-19558.62hm2,占总耕地面积的1.88%-26.34%;按照分乡镇统计(STL),全县休耕面积1396.10-17673.83hm2,占总耕地面积的1.88%-23.8%。修正模型和ESIcl为测算区域休耕规模提供了更加科学的技术方法,以期为其他类似区域开展休耕实践提供借鉴。  相似文献   

13.
1. Large‐scale comparative studies of ecological responses to anthropological stressors in rivers require measures that are consistent across a range of spatial scales. The biological trait profile of communities offers an alternative approach to traditional measures of macroinvertebrate taxonomic identity and is less constrained by biogeographic influences. 2. We compared the capacities of taxonomic composition and biological trait composition to discriminate the effects of land use (measured as percentage of the catchment in pasture) across a large geographic zone (the whole of New Zealand) in 30 sub‐catchments grouped into five ecoregions throughout the North and South Islands of New Zealand. In addition, we investigated trait consistency (i.e. whether similar traits had similar trait responses to land use at local (catchment) and broad scales). 3. The analysis of taxonomic composition showed that community structure was indeed influenced by land‐use intensity, but that relationships differed among ecoregions. In contrast, traditional assessment metrics (Macroinvertebrate Community Index, richness in Ephemeroptera, Plecoptera and Trichoptera taxa) and trait composition were uninfluenced by region. Trait responses were consistent at the broad and catchment scales, with similar traits responding to pastoral land use at both scales. 4. We used general linear modelling to investigate individual trait responses to land‐use intensity, catchment area and region, focussing on 15 trait categories known to be influenced by land‐use intensity at the catchment scale. Several trait categories varied with land‐use intensity and demonstrated consistency at both catchment and broad scales. Of these, the representation of shorter generation time, asexual reproduction and hermaphroditism, ability to lay eggs beneath the water surface, egg protection and respiration types tolerant of oxygen depletion generally increased in assemblages exposed to more intense pastoral land use. At the same time, the representation of short life duration of adults, prevalence of laying eggs at the water surface, sexual reproduction and low body flexibility decreased in assemblages exposed to land‐use intensification. 5. Our results highlight the value of developing predictive response measures that are relevant at multiple scales and provide the basis for new measures of river condition that are as effective as taxonomic identity in terms of response reliability.  相似文献   

14.
Carbon emissions from land‐use changes in tropical dry forest systems are poorly understood, although they are likely globally significant. The South American Chaco has recently emerged as a hot spot of agricultural expansion and intensification, as cattle ranching and soybean cultivation expand into forests, and as soybean cultivation replaces grazing lands. Still, our knowledge of the rates and spatial patterns of these land‐use changes and how they affected carbon emissions remains partial. We used the Landsat satellite image archive to reconstruct land‐use change over the past 30 years and applied a carbon bookkeeping model to quantify how these changes affected carbon budgets. Between 1985 and 2013, more than 142 000 km2 of the Chaco's forests, equaling 20% of all forest, was replaced by croplands (38.9%) or grazing lands (61.1%). Of those grazing lands that existed in 1985, about 40% were subsequently converted to cropland. These land‐use changes resulted in substantial carbon emissions, totaling 824 Tg C between 1985 and 2013, and 46.2 Tg C for 2013 alone. The majority of these emissions came from forest‐to‐grazing‐land conversions (68%), but post‐deforestation land‐use change triggered an additional 52.6 Tg C. Although tropical dry forests are less carbon‐dense than moist tropical forests, carbon emissions from land‐use change in the Chaco were similar in magnitude to those from other major tropical deforestation frontiers. Our study thus highlights the urgent need for an improved monitoring of the often overlooked tropical dry forests and savannas, and more broadly speaking the value of the Landsat image archive for quantifying carbon fluxes from land change.  相似文献   

15.
基于景观安全格局理论的宜兴市生态用地分类保护   总被引:6,自引:0,他引:6  
文博  朱高立  夏敏  张开亮  刘友兆  王玮 《生态学报》2017,37(11):3881-3891
生态用地是区域生态服务功能的主要供给者,对控制区域生态环境起到关键作用,开展生态用地分类与保护,对实现经济与生态协调发展、保障区域生态安全具有重要意义。以江苏省宜兴市为例,基于前人对于生态用地分类与土地利用现状分类衔接研究成果,提取土地利用现状中的生态用地,借助景观安全格局理论方法,通过系统分析水土保持、生物多样性保护、乡土文化遗产保护以及自然景观保护4个与生态用地相关的重要生态过程,运用最小累积阻力模型构建区域综合景观安全格局,并将综合景观安全格局与现状生态用地进行叠加,得到低安全水平、较低安全水平、中等安全水平以及高安全水平4种类型的生态用地,各类型面积分别占研究区生态用地总面积的32.07%、44.38%、22.07%以及1.48%,针对不同等级的不同生态用地类型,提出了划定禁止建设区、防止水体污染、建设高标准基本农田等针对性的保护措施与对策。研究结果为宜兴市的土地利用规划与管理、城市可持续发展等提供决策依据,为其他类似地区生态用地保护规划编制提供参考。  相似文献   

16.
太行山区不同植被群落土壤微生物学特征变化   总被引:22,自引:0,他引:22  
为评价太行山区不同植被群落土壤微生物学特征,比较分析了针阔混交林、针叶混交林、针叶纯林、落叶阔叶纯林、灌丛和裸露地6种不同植被群落中的土壤微生物区系、微生物生物量和呼吸强度等指标的变化.结果表明,6种不同植被群落土壤中的微生物学特征存在较大差异. 灌丛地在微生物数量和微生物生物量两项指标中均为最高,其余植被群落在这两项指标中的顺序从大到小依次为落叶阔叶纯林>针阔混交林>针叶纯林>针叶混交林>裸地,土壤呼吸强度也有相似的变化趋势.在进行退化山地的植被恢复时,应充分重视生态系统的自然恢复能力.  相似文献   

17.
基于1980—2018年土地利用变化的福建省生境质量时空演变   总被引:2,自引:0,他引:2  
分析土地利用变化引起生境质量的时空演变特征可以为区域生态文明建设提供科学依据。本研究以生态文明先行示范区福建省为例,以1980—2018年土地利用变化数据为基础,利用InVEST模型对福建省生境质量进行评估,通过地理探测器分析影响因素,结合土地利用变化规律分析福建省生境质量时空演化特征。结果表明: 研究期间,福建省主要土地利用变化类型是耕地转为林地和建设用地,林地转为耕地、草地和建设用地,草地转为林地,分别占总土地利用变化面积的8.4%、14.5%、7.6%、17.1%、6.4%和31.7%。1980—2018年,福建省总体生境质量处于较高级别(0.6~0.8),局部区域呈现生境退化和生境质量降低的趋势。影响福建省生境质量空间分异的第一主导因素是土地利用类型的变化,社会经济因素对沿海县市生境质量的影响显著高于对全域及内陆县市生境质量的影响。沿海地区建设用地快速侵占周边的林草地,使得生境加速退化,且这个过程具有不可逆性;内陆地区中心城区的生境退化会经历相似的过程,只是在速度和规模上可能低于沿海地区。从长远来看,可通过控制城市规模、发展城市生态绿化及构建生态安全格局,以减缓生境退化的速度。  相似文献   

18.
雅鲁藏布江山南宽谷风沙化土地土壤养分和粒度特征   总被引:2,自引:0,他引:2  
李海东  沈渭寿  邹长新  袁磊  纪迪 《生态学报》2012,32(16):4981-4992
在雅鲁藏布江山南宽谷区,选择流动沙地、平缓沙砾地、半固定沙地、固定沙地和覆沙河滩地等类型样地,研究了不同深度(0—10 cm、10—20 cm和20—40 cm)土壤层的养分状况和粒度特征,探讨了风沙运动对土壤粒度组成和养分含量的影响。结果表明:1)风沙化土地土壤pH值呈中性、碱性和强碱性,土壤有机质和全氮含量均很低,但全磷和全钾均很高。土壤粒度组成表现为砂粒含量(53.83%—95.93%)>粉粒(3.3%—40.5%)>粘粒(0.77%—5.68%)。2)粘粒和粉粒含量均以覆沙河滩地(分别为4.02%和27.95%)最大、半固定沙地(分别为1.35%和5.27%)最小。粘粒含量表现为覆沙河滩地>固定沙地(2.98%)>河滩流动沙地(2.89%)>平缓沙砾地(1.69%)>河岸流动沙地(1.54%)>山坡流动沙地(1.49%)>半固定沙地。不同类型沙地粉粒含量的大小顺序与粘粒含量相似,仅在山坡流动沙地和河岸流动沙地的大小顺序有所差别。砂粒含量以半固定沙地(为93.40%)最大、覆沙河滩地最小(68.05%)。不同类型沙地的砂粒含量与粉粒含量的大小顺序正好相反。3)土壤养分含量与粘粒、粉粒、极细砂粒和细砂粒等细沙物质的相关性较强,与中砂粒、粗砂粒和极粗砂粒等粗沙物质呈负相关或相关性较弱。其中,粘粒和极细砂粒含量的增加对土壤养分的增加贡献较大。流动沙丘随风沙运动而不断往复摆动的现象和土壤细颗粒的迁移和损失,对不同类型沙地和沙丘部位的土壤养分状况及其再分配过程产生较大影响。  相似文献   

19.
Contamination of the Alyth Burn by Erwinia carotovora was monitored monthly over 2 years at nine sites spread over a distance of ca 20 km. The bacterium was detected only once in the upper reaches of the river where it flows in uninhabited moorland but frequency of detection and contamination level tended to increase progressively as the river flowed through the middle reaches mostly in grassland to the lower reaches in arable land where the bacterium was almost always present. Erwinia populations rose from < 102 cells/1 before May to frequently > 103 but < 104 cells/l thereafter at sites in the arable land zone. A similar pattern was found in the grassland zone except that erwinia numbers were lower. Erwinia numbers at one site in the arable land zone were positively and negatively correlated with the river water temperature and flow rate respectively when there was a 1 month lag between the environmental data and the population recorded. More than 80% of isolates tested were E. carotovora subsp. carotovora.
Water from field drains in arable fields, especially those recently planted with potatoes, was frequently contaminated by E.c. carotovora , with numbers and a temporal pattern similar to those of the Alyth Burn. Drainage water from non-arable fields was rarely contaminated. Infected and rotting potatoes deposited in rivers temporarily contaminated the water. Survival of E. carotovora in dilute phosphate buffer was greater at pH 5˙7 than at pH 7˙7 and they survived for at least 10 d in river water.  相似文献   

20.
The demand for wood from short rotation coppice (SRC) plantations as a renewable energy source is currently increasing and could affect biodiversity in agricultural areas. The objective was to evaluate the contribution of SRC plantations to phytodiversity in agricultural landscapes assessed as species richness, species–area relationships, Shannon indices, detrended correspondence analysis on species composition, Sørensen similarities, habitat preference proportions, and species proportions found in only one land use. Vegetation surveys were conducted on 12 willow (Salix spp.) and three poplar (Populus spp.) coppice sites as well as on surrounding arable lands, grasslands and forests in central Sweden and northern Germany. SRC plantations were richer in plant species (mean: 30 species per 100 m²) than arable land (10), coniferous forests (13) and mixed forests in Germany (12). Comparing SRC plantations with other land uses, we found lowest similarities in species composition with arable lands, coniferous forests and German mixed forests and highest similarities with marginal grassland strips, grasslands and Swedish mixed forests. Similarity depended on the SRC tree cover: at increased tree cover, SRC plantations became less similar to grasslands but more similar to forests. The SRC plantations were composed of a mixture of grassland (33%), ruderal (24%) and woodland (15%) species. Species abundance in SRC plantations was more heterogeneous than in arable lands. We conclude that SRC plantations form novel habitats leading to different plant species composition compared to conventional land uses. Their landscape‐scale value for phytodiversity changes depending on harvest cycles and over time. As a structural landscape element, SRC plantations contribute positively to phytodiversity in rural areas, especially in land use mosaics where these plantations are admixed to other land uses with dissimilar plant species composition such as arable land, coniferous forest and, at the German sites, also mixed forest.  相似文献   

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