Nectar concentration and composition of 26 species from the temperate forest of South America

BACKGROUND AND AIMS: Floral nectar concentration and chemical composition of 26 plant species native to the temperate forest of southern South America are reported and the relationships with the flower type are evaluated. METHODS: Nectar concentration was measured with a hand refractometer and sugar composition was analysed by gas-liquid chromatography. Plant species were classified into flower type categories based not only on floral features but also on data from the literature and field observations on their pollinators. KEY RESULTS: Most data on nectar are new reports at the generic and/or specific level. Plant species in which more than one population was studied showed significant among-population variation in nectar sugar concentration and composition. Results showed a weak relationship between nectar traits and flower type. Many species had nectar containing 50 % or more sucrose (17 of 26 species), independent of the main pollinator. CONCLUSIONS: Considering that (a) nectar characteristics did not show a clear association with different flower types or with plant taxonomic membership, and (b) different populations of the same species showed large variability in sugar composition, the results suggest that other factors (e.g. historical and environmental) could be involved in determining the sugar composition of the highly endemic plant species from this region.     

Do leaf margins of the temperate forest flora of southern South America reflect a warmer past?

Aim   Our aims were: (1) to characterize the linear relationship between the proportion of woody dicotyledonous species with entire-margined leaves ( E ) and mean annual temperature (MAT) from a southern temperate flora that still harbours many lineages that originated under warmer climates; (2) to compare this relationship with those developed from floras of different regions of the world; and (3) to contrast temperature predictions based on leaf margins of the native southern flora versus the naturalized alien flora, mostly of boreal origin.
Location   The temperate forest of southern South America (TFSA).
Methods   At each 1° latitudinal band, we estimated E based on species latitudinal ranges and MAT from both an isotherm map and a global temperature grid. We also calculated E from five local floras located between 40 and 43° S, and from the naturalized alien flora of Nahuel Huapi National Park in southern Argentina.
Results   We found a close relationship between E and MAT for the TFSA. Equations developed from floras of the Northern Hemisphere overestimated extant temperatures of this biome by 6–10 °C at both geographical and local spatial scales. On the other hand, MAT predictions from leaf margins of the alien flora were similar to the actual MAT. A published regression between E and MAT from tropical South America was remarkably similar to the one we estimated from the TFSA. This tropical equation predicted accurately the temperatures observed for this temperate biome based on leaf margins of the native flora.
Main conclusions   Despite massive plant extinction due to environmental cooling and biogeographical isolation during the Tertiary, leaf-margin analysis reveals that the flora of the TFSA still reflects its original development under the warmer conditions of western Gondwana and its past connections with low-latitude forest floras of tropical South America.     

Early warning sign of forest loss in protected areas

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森林公园在我国自然保护区系统中的地位

本文针对我国森林公园建设发展迅速的现状,阐述了“森林公园”的自然保护性质和作用,提出“国家自然保护区系统”的概念,将森林公园与自然保护区、风景名胜区三个体系同视为“国家自然保护区系统”中的三个组成部分,并阐述了这三个体系各自的特点、地位及其相互关系。同时,还提出进一步加强森林公园管理的建议。     

海洋保护区管理与保护成效评估的方法与进展

全球物种多样性的持续下降使得生物多样性保护面临巨大挑战, 海洋生物多样性的保护任务尤其艰巨。海洋保护区是保护生物多样性的有效方式之一, 如何对其成效进行评估是当前研究热点。然而, 目前针对海洋保护区的评估体系较少, 而且评估指标多侧重于管理成效。近年来随着全球生物多样性监测网络和数据库的建立, 以及多种新技术(如遥感、声呐系统、卫星追踪、基因组学等)在海洋生物多样性监测中的应用, 使得从生态系统到基因水平的多层次连续监测成为可能。基于此, 建议未来我国海洋保护区成效评估应在充分利用新技术方法的基础上, 加强长期科学监测, 建立并完善生物多样性监测数据库和信息共享机制, 发展跨学科的综合保护成效评估体系, 加强基于生物多样性监测的保护成效评估。     

Extending the Namibian protected area network to safeguard hotspots of endemism and diversity

Namibia's state protected area network (PAN) covers 13.8% of the country's land area, but is seriously inadequate as a basis for effective biodiversity conservation. The early parks system was not designed with biological diversity in mind, and reflects instead a history of ideological, economic and veterinary considerations. Currently, parks in the Namib Desert biome make up 69% of the PAN, while savanna and woodland biomes are somewhat underrepresented (7.5 and 8.4% of their respective land areas), and the Karoo biome is badly underrepresented (1.6%). Four of 14 desert vegetation types are comprehensively protected, with 67 to 94% representation in the PAN, yet six savanna types have 0 to 2% representation by area. Mountain Savanna, a vegetation type unique to Namibia, is wholly unprotected. The status of two marine reserves, which in theory protect only 0.01% of Namibia's marine environment, needs clarification and augmentation with new reserves. Nearly 85% of Namibia's land is zoned for agriculture, so effective biodiversity protection means working outside the PAN to improve the sustainability and diversity of farming practices. Wildlife conservancies on commercial and communal farmlands show excellent potential to mitigate the ecological skew in the state PAN, with the ecological management of large areas being decentralized to rural communities in habitats otherwise neglected for conservation. Two important endemism zones, the Kaoko escarpment and coastal plain and the Sperrgebiet succulent steppe, plus the species-rich Caprivi area, offer three valuable opportunities for regional consolidation of protected areas into transboundary 'peace parks' or biosphere reserves.     

The structure and status of forest fragments outside protected areas in central Uganda

Given the extent of tropical forest deforestation and as a number of conservation programmes and local communities rely on forest fragments, it has become important to understand how fragment exploitation by local communities affects forest structure and function. The effects of forest exploitation on forest structure and status of forest fragments were investigated in 20 nonreserved forest fragments in central Uganda. Enumeration of plots showed that tree species composition of the forest fragments was 60.0%, 23.7% and 6.3% for under‐storey, middle and top canopy trees respectively. The major activity was fuel wood extraction (65%), followed by brick making (10%), cultivation and livestock paddocks (10%), charcoal burning (5%), local brew distillation and others (5%). These extractive processes caused drastic structural changes, habitat degradation and destruction. Tree stumps enumeration indicated that under storey trees formed the highest proportion for wood extraction. There was no significant difference in the level of forest exploitation (basal area loss) among forest patches of varying sizes.     

Dispersal of forest birds and trees along the Uruguay River in southern South America

The Uruguay River starts in Serra do Mar in Brazil runs through the Paranense forest and flows southward through grassland and savannas. It has a continuous gallery forest of 750 km from the southern border of the Paranense forest to the river mouth. The gallery forest extends for 100 km more along the Río de la Plata. 125 (68.7%) of the 182 species of forest birds recorded in the southern Paranense forest penetrate into the gallery forest of the Uruguay River and only 13 (7.1%) reach the end of the gallery forest (Punta Lara). The number of bird species is inversely correlated (r² = 0.942) with distance and the slope of the regression is 58.10. This means a decline in diversity with 32% of species lost per unit distance. A hundred and eighty forest tree species were recorded in the southern Paranense forest, of which 113 (62.8%) penetrate into the gallery forest of the Uruguay River, and 28 (15.6%) reach Punta Lara. The number of tree species is inversely correlated (r² = 0.976) with distance and the slope of the regression is ?45.62. This means a decline in diversity with 25% of species lost per unit distance. The Uruguay River enables the dispersal of many species of forest birds and trees from the rain forest, but species richness tends to decrease with increased distance from the source area. A clear association pattern was found for birds between size, diet, habitat use and distance reached into the gallery forest. Species of smaller body size, granivores, insectivores and those that use both the interior and exterior parts of the gallery forest advanced noticeably further along the river than larger species, carnivores, nectarivores or frugivores, and those that frequent only a part of the forest. Similarly, a clear association between dispersal mechanism, water dependence and distance reached into the gallery forest was found for trees. Species with vegetative reproduction, zoochorous species and riparian species advanced markedly longer distances along the river than, anemochorous species and non‐riparian species.     

中国保护区分类的研究

保护区是一个泛称,由于其建立的目的、要求和本身所具备的条件不同,所以具有多种多样的类型,不同类型管理的侧重点也有所区别.以保护区管理的目标为原则划分第一级分类单位,共有5个类型,即:严格的保护区、国家公园、保护景观、栖息地/物种管理区、资源管理保护区.再以保护对象原则划分第二、三级分类单位,共同构成一个完整的分类系统,以适应保护区事业日益发展的要求.     

Conservation of temperate forest birds in Chile: implications from the study of an isolated forest relict

We characterize the bird assemblage of an isolated relict temperaterainforest (Santa Inés) in terms of its structure, composition anddynamics. The relict character and long-term isolation of this forest remnant,immersed in a matrix of semiarid scrub, provide a natural experiment to assessthe consequences of long-term isolation and forest area reduction for temperatebird species. Bird surveys were conducted in a forest fragment and thesurrounding scrub matrix between April 1999 (austral autumn) and October 2000(austral spring) on a seasonal basis. Within the forest fragment wedistinguished two microhabitat types: creeks and areas far from creeks (i.e.slopes). A total of 36 species were recorded in the study site, of which 21were inside the relict forest. Highest bird abundance and richness wererecorded during winter and spring, and these were always higher in creek plotsrather than slope plots. Comparisons between this assemblage and thosedistributed in the continuous temperate forest (located more than 900km southwards) indicate that this bird assemblage shares moresimilarities, with regard to bird species composition, to southern temperateforest localities and to other relict forests, than to nearer scrub habitats.However, there are eight species, endemic to temperate forests in southern SouthAmerica, missing from our system. In this regard, our analyses indicate thatthese eight endemic species should be of great conservation concern and willlikely be the ones that will go extinct first if the fragmentation of thetemperate forest continues.     

Climate as a determinant of dung beetle response to native forest replacement by cattle pastures in South America

Anthropogenic disturbance in natural ecosystems reduces the number of species in biological communities and homogenizes their composition across different regions. Climate is one of the main abiotic determinants of species distributions and different factors were proposed as the main climatic drivers. Here we explored the role of regional climate on the local response of dung beetle assemblages to the replacement of native forest by cattle pastures in South America by simultaneously contrasting three climatic hypotheses: energy, seasonality and heterogeneity. We compiled a database by searching published studies comparing dung beetle richness and composition between both native forests and cattle pastures. We calculated the proportional difference in species richness and composition between habitat types. As explanatory variables, we used seven abiotic variables grouped into the three climatic hypotheses. Energy/Productivity: mean annual temperature (°C/year) and total annual precipitation (mm/year). Seasonality: annual thermal amplitude (°C/year), the average coefficient of variation of monthly precipitation and the coefficient of average monthly variation in temperature. Heterogeneity: coefficient of variation of mean annual temperature, coefficient of variation of mean annual precipitation. Using regression analyses and a model selection procedure, we found differences in species richness between native forests and cattle pastures were explained by the coefficient of variation of mean annual precipitation, whereas changes in species composition were explained by total annual precipitation and the coefficient of variation of mean annual precipitation. The response of dung beetle assemblages to livestock grazing in South American forests was associated with precipitation variation. The heterogeneity hypothesis better explained changes in species richness following forest replacement by cattle pastures, while both energy/productivity and heterogeneity hypotheses explained the changes in species composition.     

生态保护红线战略视域下自然保护地如何划界和分区管控?

本文在生态保护红线战略背景下, 探讨自然保护地如何通过合理划界、分区管控及相应管理措施来处理人地关系。主要观点包括: 在国家生态保护红线战略指导下开展自然保护地边界划定及分区管控, 不仅是单一的自然科学问题, 同时也是多目标管理问题; 生态保护红线并不仅是一条静态物理空间划线, 而且也是生态系统动态管控的基线(baseline); 在生态保护红线战略思想下, 自然保护地分区管控需要考虑地理差异性, 应因地制策、因时施策。生态保护红线内区域的人地关系的处理需要明确保护地可建设范围、科学许可自然资源可利用方式, 应当对保护地的生态系统特征进行研究, 充分论证其对人类活动的承受能力, 在保护自然生态系统的前提下, 最终将人类活动控制在生态系统稳定性可以接受的“基线”之内。     

天津市自然保护地与区域生境质量的时空演变格局

生境质量是反映区域生物多样性水平的重要指标,而规划科学、管理有效的自然保护地对于维护生境质量、巩固区域生态安全具有重要作用。以天津市为例,运用InVEST模型Habitat Quality模块评估了天津市2000、2005、2010、2015、2018年生境质量时空变化格局,基于叠加分析自然保护地内外生境质量变化探讨自然保护地对维护区域生境质量发挥的作用。结果表明：(1)2000—2018年间天津市生境质量总体下降了13.18%,并呈现出明显的由中心城区向环城四区扩散的趋势,高质量区域仅占天津陆域国土面积的4%,主要分布在天津北部山区和于桥水库、团泊洼、北大港、大黄堡等湿地。(2)天津保护地空间分布上呈集中分布态势,覆盖了天津市约75%的高质量生境区域和25%的较高质量生境区域。(3)从整体上看不同类型的自然保护地内生境质量保护效果不同,自然保护区优于其它类保护地,其生境质量明显得到提升。所有保护地中有10处保护地生境质量略有下降,但低于全域下降水平,只有盘山风景名胜区和古海岸与湿地自然保护区生境质量下降高于全域平均水平。(4)自然保护地对天津市生境质量下降的趋势起到了一定缓冲作用,其...     

Role of African protected areas in maintaining connectivity for large mammals

The African protected area (PA) network has the potential to act as a set of functionally interconnected patches that conserve meta-populations of mammal species, but individual PAs are vulnerable to habitat change which may disrupt connectivity and increase extinction risk. Individual PAs have different roles in maintaining connectivity, depending on their size and location. We measured their contribution to network connectivity (irreplaceability) for carnivores and ungulates and combined it with a measure of vulnerability based on a 30-year trend in remotely sensed vegetation cover (Normalized Difference Vegetation Index). Highly irreplaceable PAs occurred mainly in southern and eastern Africa. Vegetation cover change was generally faster outside than inside PAs and particularly so in southern Africa. The extent of change increased with the distance from PAs. About 5% of highly irreplaceable PAs experienced a faster vegetation cover loss than their surroundings, thus requiring particular conservation attention. Our analysis identified PAs at risk whose isolation would disrupt the connectivity of the PA network for large mammals. This is an example of how ecological spatial modelling can be combined with large-scale remote sensing data to investigate how land cover change may affect ecological processes and species conservation.     

Rivers in peril inside and outside protected areas: a systematic approach to conservation assessment of river ecosystems

This paper establishes a framework within which a rapid and pragmatic assessment of river ecosystems can be undertaken at a broad, subcontinental scale, highlighting some implications for achieving conservation of river biodiversity in water‐limited countries. The status of river ecosystems associated with main rivers in South Africa was assessed based on the extent to which each ecosystem had been altered from its natural condition. This requires consistent data on river integrity for the entire country, which was only available for main rivers; tributaries were thus excluded from the analyses. The state of main river ecosystems in South Africa is dire: 84% of the ecosystems are threatened, with a disturbing 54% critically endangered, 18% endangered, and 12% vulnerable. Protection levels were measured as the proportion of conservation target achieved within protected areas, where the conservation target was set as 20% of the total length of each river ecosystem. Sixteen of the 112 main river ecosystems are moderately to well represented within protected areas; the majority of the ecosystems have very low levels of representation, or are not represented at all within protected areas. Only 50% of rivers within protected areas are intact, but this is a higher proportion compared to rivers outside (28%), providing some of the first quantitative data on the positive role protected areas can play in conserving river ecosystems. This is also the first assessment of river ecosystems in South Africa to apply a similar approach to parallel assessments of terrestrial, marine, and estuarine ecosystems, and it revealed that main river ecosystems are in a critical state, far worse than terrestrial ecosystems. Ecosystem status is likely to differ with the inclusion of tributaries, since options may well exist for conserving critically endangered ecosystems in intact tributaries, which are generally less regulated than main rivers. This study highlights the importance of healthy tributaries for achieving river conservation targets, and the need for managing main rivers as conduits across the landscape to support ecological processes that depend on connectivity. We also highlight the need for a paradigm shift in the way protected areas are designated, as well as the need for integrated river basin management plans to include explicit conservation visions, targets, and strategies to ensure the conservation of freshwater ecosystems and the services they provide.     

Parasites in marine protected areas: success and specificity of monogeneans

The effect of a marine protected area on the Lamellodiscus spp. monogenean community was tested by comparing the communities of parasites of Diplodus sargus inside and outside of the area. A total of 104 D. sargus were dissected harbouring 1280 monogeneans from the genus Lamellodiscus and belonging to 11 species. No modification in the global parasite community linked with the protection of the host populations was revealed. The most abundant and less specific parasite species, Lamellodiscus elegans , however, increased its abundance in the protected area. A significant relationship was found between parasite host range and the percentage of infected hosts. A significant relationship also occurred between epidemiological and genetic distances for the parasite species found. The results are discussed in term of parasite success and specificity and the importance of taking into account parasitism in the biological conservation of hosts.     

The implications of Tertiary and Quaternary sea level rise events for avian distribution patterns in the lowlands of northern South America

Aim To assess the correspondence between current avian distributions in the lowlands of northern South America with respect to the hypothesized importance of sea level rise and other events over the past 15 million years on speciation. Location Tropical lowlands of north‐western South America. Methods To establish which bird taxa may have originated in each area of endemism, I examined the ranges of all bird species occurring in the Pacific and the Caribbean lowlands. To determine land and sea distribution during a sea level rise of 100 m in north‐western South America and eastern Central America, I traced the 100 m contour line from the Geoatlas of Georama and the Global 30‐Arc‐Second Elevation Data (GTOPO30) produced by the US Geological Survey. Results During a sea level rise of ～100 m, marine incursions would have occurred from the Caribbean Sea and the Pacific Ocean. Several areas of tropical forest and dry/arid vegetation would have been isolated, currently known as the Darién, Chocó, Nechí, Catatumbo, Tumbesian and Guajiran areas of animal and plant endemism. Main conclusions A large part of the high diversity of forest and nonforest birds and other animals and plants in the Pacific rain forest and the Caribbean woodland likely arose as the result of sea level rises, dispersal and other geological and climatic events.     

帽儿山温带落叶阔叶林通量塔风浪区生物量空间格局

采用网格法在帽儿山温带落叶阔叶林通量塔风浪区(1500 m×400 m)内设置直径为20 m的圆形样地106个,运用地统计学方法和回归分析法研究了乔木生物量空间格局及其驱动因子。结果表明,风浪区总生物量平均值为153.63 Mg/hm~2,变异系数为37.89%;根冠比平均0.25(变化范围0.18—0.36)。总生物量、地上生物量和地下生物量的空间自相关显著,半方差模型的结构比分别为0.50、0.61和0.50,空间异质性尺度分别为276 m、198 m和375 m。硬阔叶林与杂木林的生物量组分和根冠比差异均不显著,但以胸高断面积(BA)为协变量,生物量组分差异显著。硬阔叶林和杂木林生物量组分与BA均呈极显著的线性正相关关系,BA可以解释总生物量和地上生物量空间变异的85%以上,表明局域尺度上BA可作为森林乔木生物量的预测因子。两种林型的生物量与优势高呈对数线性关系,但相关程度较低(R~20.41)。杂木林的各生物量组分与坡度显著正相关,但硬阔叶林的关系不显著。帽儿山落叶阔叶林乔木生物量受BA、优势高、林型、坡度和坡向共同驱动而存在空间变异,因此在整合通量塔与地面碳汇测量时需要考虑空间异质性。     

自然保护地保护成效评估: 进展与展望

自然保护地(protected areas)保护成效是指自然保护地对主要保护对象的保护效果, 及其在维持生物多样性和保障生态系统服务功能等方面的综合成效。近年来自然保护地保护成效评估逐渐成为国内外的研究热点之一。 本文分别从不同空间尺度、评估对象、评估方法以及评估指标等方面综述了相关的研究进展。总体来看, 近年来的研究已基本覆盖了全球、区域、国家和单个自然保护地等不同尺度, 针对森林、湿地、草地和荒漠等代表性生态系统以及野生动植物等主要保护对象进行了评估, 发展了“matching”技术等更为有效的分析方法, 探索了系统的自然保护地保护成效评估指标体系, 并应用一些指标进行了保护成效的案例研究。自然保护区(nature reserve)是我国自然保护地的主体, 近年来我国自然保护区相关管理部门也相继开展了保护成效评估工作, 建议未来进一步加强自然保护区网络尺度和各类型自然保护区的保护成效评估研究, 将自然保护区保护成效评估与管理评估相结合, 研究自然保护区保护成效面临的新问题和潜在影响, 为提升我国自然保护区管理质量提供科学依据。