Ecotonal Areas Research Articles

ODONATE FAUNA (INSECT: ODONATA) OF TWO PONDS IN THE CERRADOPANTANAL ECOTONE, AQUIDAUANA, MS

Knowing the biodiversity of a given site is the first step in establishing strategies for its conservation, monitoring and sustainable use. The objective of the present study was to catalogue the Odonata community of two ponds in the Cerrado-Pantanal ecotone area. Collections were carried out between October 2012 and September 2013, encompassing different hydrological seasons. This study presents the first systematized survey of Odonata for lentic environments in the region. A total of 347 individuals were recorded, distributed in 41 species, 22 genera and three families. The suborder Zygoptera was represented by the Coenagrionidae and Lestidae families, while the suborder Anisoptera was represented by the Libellulidae family. The Acanthagrion, Erythemis and Erythrodiplax genera were the most representative. The results indicate that there is seasonality in the occurrence of the species. The wide diversity found in lentic environments emphasizes the importance of long-term monitoring of these ecosystems, in order to understand the effect of seasonality and of anthropic alterations to the surrounding environment on the Odonata community.

Reclamation of desert land to continuous cotton cropping affects soil properties and microbial communities in the desert-oasis ecotone of Xinjiang, China

A large area of desert land in the desert-oasis ecotone in northwestern China is being reclaimed for continuous cotton production for several decades. However, little is known about the possible effect of reclamation and long-term monocultural cotton cultivation on soil properties and microbial communities in the desert-oasis ecotone area. Soil samples were collected from the 0–20-cm mineral soil from croplands that had been continuously planted cotton for 5, 25, and 50 years after reclamation, as well as a desert land (t = 0, before reclamation, used as the control). Soil physical and chemical properties, enzyme activities, and bacterial and fungal community diversities were determined. Soil organic carbon, total nitrogen, and enzyme activities increased up to 25 years after reclamation, and further monocultural cotton cropping was not beneficial to improve soil quality. Soil urease, alkaline phosphatase, and sucrase activities increased by 121~205%, 100~167%, and 206~719% in croplands as compared with the desert land, respectively, after reclamation with the highest value at 25 years of cotton cultivation. Bacterial richness and diversity increased from desert land to the 5-year-old cropland and then remained stable after 5 years of cotton cropping, and soil fungal richness and diversity were not affected by reclamation and cropping years. Crop rotation or fallow should be considered to maintain or improve soil quality over the long-term monocultural cropping.

Геоботанические исследования на Кавказе: обзор материалов Международной конференции «Флора и заповедное дело на Кавказе: история и современное состояние изученности» (Пятигорск, 22–25 мая 2019 г.)

The International conference “Flora and conservation in the Caucasus: history and current state of knowledge” dedicated to the 130-year anniversary of the Perkalsky Arboretum took place at 22–25 of May 2019 in Pyatigorsk (Stavropol Territory) on the base of the Pyatigorsk Museum of local lore and natural history. The participants were from 11 cities of Russia and 7 Republics of the Caucasus and represented 14 institutions. Proceedings of the conference were published by the beginning of the meeting the book of abstracts includes 49 papers on the study of vascular plants, bryophytes, lichens and fungi, plant communities, as well as the protection of rare and endangered species, unique plant communities, and ecological problems in the Caucasus. The following geobotanical topics were highlighted in 13 papers: forest communities (3 reports), meadow and steppe vegetation (2), xeric open forests (2), communities of ecotone areas (1), structure of populations of rare plant species (3), as well as the history and current status of nature protected areas (2). The great emphasis has been focused on the study of floristic composition and plant populations. Thus, the conference showed that very few studies от vegetation are currently carried out in the Caucasus, and a lot of districts are not affected by the research. The greatest attention is paid to forest vegetation while meadow, steppe, alpine heath and xerophytic communities are studied rather poorly. Besides, there are “white spots” — mire, floodplain and aquatic vegetation. In nowadays, when the anthropogenic impact on the plant cover of the Caucasus is intensively increasing, it is especially important to study natural undisturbed communities preserved in protected natural areas. Another important issue is the conservation of the unique vegetation cover of the whole Caucasus. Thus, the study of vegetation of this region opens a wide field for researchers using various methods of modern plant science.

Study on optimized combination and utilization model of agricultural and animal husbandry resources in mountain ecotone

[Purpose] The development of agriculture and animal husbandry in Tibet is basically based on the interlaced development of agriculture and animal husbandry in mountainous areas. The interlaced agricultural and animal husbandry areas in mountainous areas are the unity of special, harmonious and harmonious regional small environment. The special attributes of mountainous areas determine the rich agricultural and animal husbandry resources, ecological development cycle areas, characteristic agricultural products areas and tourism. The division and regionalization of recreational zones and the optimal combination and utilization of agricultural and animal husbandry resources in mountainous ecotone have very important effects on promoting the benign cycle of regional agricultural and animal husbandry economic development, the development of urban integration and the protection of industrial ecological environment. How to develop and construct a new type of "environment-friendly and resource-saving" agricultural and animal husbandry areas is very important. It is of great practical significance to promote the development of regional agriculture and animal husbandry industry, to establish an efficient production system of agriculture and animal husbandry and to speed up the increase of farmers' and herdsmen's income. Rational and effective utilization of various beneficial resources can effectively solve the problems of material shortage, resource shortage and contradiction between supply and demand, and ensure the interlaced agriculture and animal husbandry economy in Tibet's mountainous areas. Sustainable development. [Method]On the basis of domestic and foreign literatures, this paper analyses and evaluates in detail the optimal combination and utilization mode of agricultural and animal husbandry resources in mountainous ecotone area by means of management induction, [Result]that is, the modern high-efficiency utilization mode of new energy, the green integration development mode of "chain fusion" in seed and culture, and the multi-level agricultural capital. Four basic modes, i.e. the mode of efficient utilization of resources and the mode of recreational sightseeing and sightseeing in mountainous agriculture and animal husbandry. [Conclusion] The above four modes of optimal combination and utilization of agricultural and animal husbandry resources are the basic macro-combination modes of agricultural and animal husbandry resources in the mountainous ecotone of Tibet. They are discussed in detail from the perspectives of natural resources utilization, agricultural products production and processing, agricultural and animal husbandry production and construction, and eco-tourism development in order to provide better services. Development and construction of agricultural and animal husbandry circular economy in Tibet. Finally, according to the characteristics of Tibet's own development, this paper puts forward to promote the integration of scientific concepts, the strength of scientific and technological support, and the fund guarantee system in the basic fields, and to strengthen the integration of farmer-herdsman cooperatives and market organizations in practical application. Reference and extension of the model, incentive and compensation security system, etc., for the future development of mountain-type interlaced agriculture and animal husbandry in Tibet circular agricultural and animal husbandry and resource optimization and combination of construction to provide a reference and research results.

SEASONAL AND SPATIAL VARIATION OF ROAD-KILLED VERTEBRATES ON BR330, SOUTHWEST BAHIA, BRAZIL

In the present study, we aimed to characterize and quantify the vertebrates road-killed along 12.8 km of the BR-330 highway in southwestern Bahia. The road is surrounded by patches of Atlantic Forest and Caatinga and by human-modified areas. From May/2012 to August/2013, we performed 35 surveys, monitoring 448 km in total. During this period, we registered 146 road-killed individuals belonging to 60 species (35 birds, 15 reptiles, 7 mammals and 3 amphibians). The species most likely to be road-killed in the study area were the toad Rhinella jimi and the snakes Oxyrhopus trigeminus and Sibynomorphus neuwiedi . The Jaccard index showed higher values when compared to the observed richness of road-killed species, which is corroborated by the ten new species recorded during five additional surveys from August/2015 to July/2016. The number of road-killed vertebrates was significantly higher in the rainy season than in the dry season. We identified 26 road-kill hotspots along the studied stretch of road. The presence of water bodies associated with vegetational landscape surrounding these hotspots may be a reason for the higher concentration of road-kills. Besides being one of the few studies conducted in an ecotonal area in the northeast of Brazil, our data indicate some important patterns that should be considered for regional and national policies on impact mitigation.

A long-term study of a snake community in north-western Tuscany (central Italy): population structure and density patterns

We analysed a snake species community of a Mediterranean 0.2 ha ecotonal area during a 21 year time span, monitoring two colubrid and one viperid snake species. We carried out analyses in seven years (1997, 1999, 2002, 2004–2005, 2016–2017) that had similar sampling efforts and, in the last two years of short-term monitoring, we applied a recently proposed monitoring protocol of the Italian Environment Ministry. In total, we captured 172 distinct individuals, 61 whip snakes (Hierophisviridiflavus), 26 barred grass snakes (Natrixhelvetica) and 85 asp vipers (Viperaaspis). Regarding the long-term monitoring period, whip snakes were captured on average about nine times per year, grass snakes were captured four times per year and asp vipers were found 12 times per year. Captures decreased in whip snakes, while increased in grass snakes and remained constant in asp vipers. In 2016 and 2017, we captured 10 whip snakes, 19 grass snakes and 31 asp vipers. Density estimates of snake species (0.5 H.viridiflavus/ha, 0.3 N.helvetica/ha and 0.7 V.aspis/ha) differ, to a certain extent, from published results for some other areas of central, northern and western Europe, perhaps depending on the approach applied for habitat suitability estimation. The average body size between two years differed neither for whip snakes nor for grass snakes, but it decreased significantly in asp vipers.

Secondary subtropical Atlantic forests shelter a surprising number of rare tree species: outcomes of an assessment using spatially unbiased data

There is an increasing interest in secondary forests due to their potential to shelter a substantial amount of tree species. Hence, this study sought to assess the rarity form of 646 arborescent species occurring in secondary stands of three forest types within the Brazilian subtropical Atlantic Forest biodiversity hotspot. The species were classified into one of seven rarity forms encompassing population size, habitat preference, and geographical distribution. Data gathered within 418 systematically distributed 0.4 ha sample plots were used. Among all recorded species (dbh ≥ 10 cm), 67% were classified into one of the seven rarity forms at least in one forest type. Approximately 50% of the species found in each forest type were rare. Myrtaceae was the family with the greatest number of rare species, followed by Fabaceae, Lauraceae, and Melastomataceae. Yet, rare species represented a diminished portion of the ~ 90,000 sampled individuals: less than 5% of the trees in each forest type. Rare species with scarce populations—i.e., forms 1, 3 and 7—represented more than 40% of the total species richness recorded in each forest type. The sample plots located in old-growth forests, ecotone areas, or areas with specific environmental conditions (e.g., hydromorphic soils), often showed larger proportions of rare species. Public protected areas appeared to be important for conservation as some species were observed exclusively in these areas and were singletons. Quadratic plateau regression models brought up evidence that the mean proportion of recorded rare species did not increase substantially in sample size classes greater than 70–80% of the reference samples.

漓江水陆交错带土壤理化性质及其分布特征

PDF HTML阅读 XML下载 导出引用 引用提醒 漓江水陆交错带土壤理化性质及其分布特征 DOI: 10.5846/stxb201805091026 作者: 作者单位: 珍稀濒危动植物生态与环境保护教育部重点实验室,珍稀濒危动植物生态与环境保护教育部重点实验室,广西师范大学生命科学学院;珍稀濒危动植物生态与环境保护教育部重点实验室,珍稀濒危动植物生态与环境保护教育部重点实验室,珍稀濒危动植物生态与环境保护教育部重点实验室,珍稀濒危动植物生态与环境保护教育部重点实验室 作者简介: 通讯作者: 中图分类号: 基金项目: 广西自然科学青年基金项目（2016GXNSFBA380030）；广西壮族自治区中青年教师基础能力提升项目（ky2016YB062）；2017年度自治区级大学生创新创业训练计划项目（201411000124）；2017年度广西高校优秀教师出国留学项目 Soil physico-chemical properties and distribution characteristics in an aquatic-terrestrial ecotone of the Lijiang River, southwest China Author: Affiliation: Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection，Ministry of Education,,,,Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection，Ministry of Education 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:水陆交错带是水生生态系统与陆地生态系统之间的过渡带，是一种典型的生态交错区，承载着能量流动、物质循环和信息交换的重要作用。土壤作为水陆交错带系统的重要组成部分，是水陆交错带功能实现的基础之一。鉴于此，以桂林漓江水陆交错带纵向梯度（上游、中游、下游）不同植被覆盖条件下的土壤为研究对象，采用野外取样调查、实验分析与统计检验相结合，系统的分析了土壤理化性质及其分布特征，旨在为该区域退化生态系统恢复与重建提供依据。结果表明：11个土壤理化性质，其中5个指标（土壤含水量、全氮、全磷、速效氮和速效钾）在上游、中游和下游均差异性显著。不同梯度下的土壤理化性质的相关性及相关性大小也不尽相同，但在总体上存在一些较相似的变化规律，如上游、中游和下游的土壤容重和孔隙度均呈现显著负相关，土壤全磷和有机质与多数土壤化学性质呈显著正相关；土壤含水量在下游与多数土壤化学性质均显著相关，但在上游仅与土壤全磷显著负相关。PCA主成分分析表明，土壤容重、土壤孔隙度和土壤全磷含量的贡献均大于其他环境因子的平均贡献率，体现了它们是影响漓江水陆交错带土壤理化性质的重要环境因子。 Abstract:The aquatic-terrestrial ecotone is a transitional zone between aquatic and terrestrial ecosystems. It is a typical eco-transitional zone and plays an important role in energy flows, material circulation, and information transformation. Soil, as an important part of the aquatic-terrestrial ecotone, is one of the basic functional aspects of an aquatic-terrestrial ecotone. This study aimed to provide scientific guidance for the restoration of a degraded aquatic-terrestrial ecotone. To do so, a typical area of the aquatic-terrestrial ecotone of the Lijiang River, Guilin, southwest China were selected as the sampling site. We measured eleven soil physico-chemical properties, including the following soil chemical properties: soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), available nitrogen (AN), available phosphorus (AP), available potassium (AK), and soil pH, as well as the following soil physical properties: soil water content (SWC), bulk density (BD), and soil porosity (PS). We analyzed the relationships between the soil physico-chemical properties of different distributed community types by employing methods of field investigation and experimental testing using basic statistics including One-way ANOVA, the Tukey-Kramer HSD test, and Principal Component Analysis (PCA) across a longitudinal gradient (upstream, midstream, and downstream) in an aquatic-terrestrial ecotone of the Lijiang River. The results showed that SWC, TN, TP, AN, and AK have significant differences across the longitudinal gradient (upstream, midstream, and downstream) of aquatic-terrestrial ecotones. Although the correlations and the intensity of the correlations between soil physico-chemical properties across the gradient were different, there were some similarities. Of the soil physical properties, bulk density and soil porosity are significantly negatively correlated, while TP and SOM have a significant positive correlation with most of the soil chemical properties across the longitudinal gradient of the aquatic-terrestrial ecotone. Soil water content was significantly positive correlated with most of the soil chemical properties in the downstream region, but only had a significantly negative correlation with TP in the upstream region. A principal component analysis indicated that soil bulk density, soil porosity, and soil total phosphorus contributed more than the other environmental factors to PCA1 and PCA2, which were important predictors of the distribution of different community types in the aquatic-terrestrial ecotone of the Lijiang River. 参考文献 相似文献 引证文献

Riparian vegetation structure and soil variables in Pandeiros river, Brazil

Abstract This study analyzed the floristic, structural variations and their relationships with soil variables in two stretches of riparian vegetation in an ecotonal region between savanna and semiarid zones. We following the hypothesis of despite the proximity between the sampled areas, soil conditions are distinct and lead to changes in structure and composition of the vegetation. This study was development at EPA of Pandeiros River, Minas Gerais, where we allocated 140 plots of 10 × 10 m (100 m2), with 10 m distance between plots, in two areas of riparian vegetation, named Larga and São Domingos (70 plots in each area), where we conducted the phytosociological survey and collected soil samples. In total, 751 arboreal individuals were sampled, distributed in 89 species and 35 botanical families. The areas differed strongly in structure and species composition, and showed floristic peculiarities and influence of surrounding vegetation. Despite of low distance between the sampled areas, these are singular environments influenced by different soils, by the mixed composition of the ecotonal area and the anthropogenic impacts to which they are exposed.

Serological evidence of canine arthropod-borne infections in an ecotone area of a natural reserve at the Pantanal, Brazil

Arthropod-borne infections are dependent on environmental conditions; therefore, anthropomorphic meddling may disrupt the natural balance that maintains wildlife. It is common to find dogs roaming in Brazilian natural reserves, what favors the spillover of pathogens among species. The aim of this study was to determine the canine seroprevalence of Ehrlichia canis, E. ewingii, Anaplasma platys, A. phagocytophilum, Borrelia burgdorferi, Leishmania infantum and Dirofilaria immitis using 84 serum samples from dogs from the border area of the SESC-Pantanal reserve (RPPN SESC-Pantanal 16°40 51 S;56o17 45 W) stored at the Laboratorio de Protozoologia e Imunomodulacao, Instituto Oswaldo Cruz. Samples were tested with SNAP Canine Leishmania Antibody Test (IDEXX Laboratories) or DPP canine visceral leishmaniasis test (Bio-Manguinhos) for the presence of L. infantum antibodies and with SNAP 4Dx Plus Test (IDEXX Laboratories) for D. immitis, Ehrlichia spp., Anaplasma spp. and B. burgdorferi seroprevalences.The seroprevalence for tick-borne parasites was 79.8%, 13.1% for L. infantum and 7.1% for D. immitis. Since tick-borne parasites were the most frequent among the examined dogs it may be suggested that these parasites, ticks and hosts display special resilience skills to overcome the hostile local conditions. The low L. infantum prevalence suggests that the local biodiversity, especially the bird abundance, depurates Leishmania circulation. The mosquito-borne D. immitis prevalence was higher than expected, suggesting that the local flooding regime provides suitable mosquito-breeding spots. On the other hand, the only known vector in the area feeds on birds, therefore reducing mosquitoes worm burden and imparing D. immitis transmission.

Parasitism, sexual dimorphism and effect of host size on Apocephalus attophilus offspring, a parasitoid of the leaf-cutting ant Atta bisphaerica.

Atta bisphaerica (Forel) is a leaf-cutting ant that specializes on grass and causes productivity losses in sugar cane fields and pastures. Three phorid species, Apocephalus attophilus (Borgmeier), Myrmosicarius grandicornis (Borgmeier) and Eibesfeldtphora bragancai (Brown), have been found parasitizing A. bisphaerica workers. These parasitoids can reduce plant material transported into the nests and ant traffic on the trails. Therefore, phorid flies have been considered potential biological control agents for leaf-cutting ants. Here, we evaluated which parasitoid species attack the leaf-cutting ant A. bisphaerica in pasture areas of a Brazilian Savannah-Atlantic Forest ecotone, parasitism rate, effect of host size, sexual dimorphism and sex ratio of the emerged parasitoids. Four nests of A. bisphaerica were selected in pasture areas from August 2016 to August 2017, with 400 workers collected from each colony monthly. A total of 23,714 A. bisphaerica workers were collected during the study, of which 236 (0.99%) were parasitized by phorid parasitoids. Apocephalus attophilus, E. bragancai and M. grandicornis parasitized 217, 17 and 2 ants, respectively. The higher parasitism rate was found in the hottest/rainy season of the year. Non-parasitized ants survived longer than those parasitized by A. attophilus. The larval and pupal periods of this parasitoid were 2.2 ± 0.8 and 16 ± 1.4 days, respectively, and the number of pupae per parasitized ant ranged from 1 to 7. The number of A. attophilus pupae per host increased with the host head size. Likewise, the size of the adult parasitoids also increased according to the host ant. Apocephalus attophilus females were larger than males and the sex ratio (male: female) did not differ from 1: 1. Our results showed that A. attophilus would be a potential biocontrol agent of leaf-cutting ants because it produces multiple larvae per host, allowing a great production of parasitoids with short developmental time and kills the host ant faster than other phorids.

Genetic and Historical Colonization Analyses of an Endemic Savanna Tree, Qualea grandiflora, Reveal Ancient Connections Between Amazonian Savannas and Cerrado Core.

The evolutionary processes underlying the high diversity and endemism in the Cerrado, the most extensive Neotropical savanna, remain unclear, including the factors promoting the presence and evolution of savanna enclaves in the Amazon forest. In this study, we investigated the effects of past climate changes on genetic diversity, dynamics of species range and the historical connections between the savanna enclaves and Cerrado core for Qualea grandiflora, a tree species widely distributed in the biome. Totally, 40 populations distributed in the Cerrado core and Amazon savannas were analyzed using chloroplast and nuclear DNA sequences. We used phylogeographic, coalescent and ecological niche modeling approaches. Genetic data revealed a phylogeographic structure shaped by Pleistocene climatic oscillations. An eastern-western split in the Cerrado core was observed. The central portion of the Cerrado core harbored most of the sampled diversity for cpDNA. Ecological niche models predicted the presence of a large historical refuge in this region and multiple small refuges in peripheral areas. Relaxed Random Walk (RRW) models indicated the ancestral population in the north-western border of the central portion of the Cerrado core and cyclical dynamics of colonization related to Pleistocene climatic oscillations. Central and western ancient connections between Cerrado core and Amazonian savannas were observed. No evidence of connections among the Amazonian savannas was detected. Our study highlights the importance of Pleistocene climatic oscillations for structuring the genetic diversity of Q. grandiflora and complex evolutionary history of ecotonal areas in the Cerrado. Our results do not support the recent replacement of a large area in the Amazon forest by savanna vegetation. The Amazonian savannas appear to be fragmented and isolated from each other, evolving independently a long ago.

Manfreda santana-michelii (Asparagaceae subfamily Agavoideae), a Striking New Species from Sierra Madre del Sur in Western Mexico

Manfreda santana-michelii is described from ecotone areas between open pine-oak forest and savannoid vegetation in the northern range of the Sierra Madre del Sur, in western Mexico. Morphologically, the new species resembles M. involuta and M. singuliflora, but differs from both of these by the development of denticulate margins on the leaves, racemose inflorescences, two pedicellate, tubulate, ascending flowers per node, a straight perigone tube, and 0.3–0.5 cm long filaments that are inserted just at the base of the perigone lobes. Illustrations, photographs for the new species and similar taxa, and a key to identify Manfreda in western Mexico accompany the description.

Limiting similarity mediates plant community niche hypervolume across a desert-steppe ecotone of Inner Mongolia

Quantifying niche space occupation based on assessments of multiple resource utilization traits can improve an understanding of plant species coexistence within communities of varying resource availability. We used an ‘occupied functional niche space (OFS)’ method based on multiple leaf traits to examine how plant communities accommodate changes in water availability within a desert-steppe ecotone spanning a limited geographic region. Our study area (western Inner Mongolia) spanned a range of conditions from highly water-limited (desert, D) to less water-limited (desert steppe, S), with two areas capturing the ecotonal boundary between these two vegetation types – partial desert (pD) and partial desert steppe (pS). We tested whether environmental filtering, heterogeneity, or limiting similarity drove trait convergence versus divergence of OFS across a desert-steppe ecotone. We quantified changes in plant community weighted means of both functional (specific leaf area and leaf dry matter content) and stoichiometric (leaf nitrogen content and leaf carbon concentration) leaf traits. OFS in the ecotonal areas (pS and pD) had larger volumes than the most mesic (S) subregion. However, divergence in the centroid of OFS was apparent for the driest (D) subregion, relative to the other three sub-regions. Underlying changes to OFS were changes in plant functional types, with more functional groups found in D and the fewest in S. For community-weighted leaf traits, SLA was highest in the ecotone area (pD and pS), while lowest in D. Further, community weighted means based on leaf dry matter content in D was the highest of all sub-regions, while both community weighted means based on leaf nitrogen content and community weighted means based on leaf dry matter content decreased as precipitation decreased, consistent with expectations. Our results suggest that communities alter both the volume and the centroid of functional trait space to adjust to decreasing water resource availability. We posit that limiting similarity (i.e. competitive exclusion) in water-resource use traits among species, supported by changes in life histories, led to OFS divergence in the ecotonal areas (pS and pD) and D, while environmental filtering may have led to convergence of OFS within the most mesic region (S) as water-stress lessons. In total, our results contribute knowledge as to how plant communities alter trait space in resource acquisition across climatic gradients, and underscores the utility of multi-trait approaches in understanding patterns of species coexistence in response to climatic changes.

Impact of the Urbanisation Process in the Availability of Ecosystem Services in a Tropical Ecotone Area

Urbanisation has been a main cause of land use land cover (LULC) change worldwide, often with irreparable consequences to the provision of ecosystem services. Despite an increase in quantitative assessments of ecosystem service values (ESV) related to LULC changes, data are scarce for ecotones, such as the agreste in northeast Brazil (a transitional area between the Atlantic Forest and the Caatinga biomes). The benefit transfer method was used to quantify changes in ESV between 1989, 2007 and 2014 due to urbanisation in the microwatershed Riacho das Piabas (3660 ha) in the agreste of Paraíba. Remote sensing techniques and a geographic information system were used to quantify LULC changes. Loss of arboreal vegetation (covering 46% of the study area in 1989 and 5% in 2014) was the key factor driving the 73.2% decline in the total ESV (from US$ 13.7 million to US$ 3.7 million in 2017 values). LULC changes resulted in losses of 89% in the estimated value of eight ecosystem services, including climate regulation, water flow regulation, moderation of disturbance, nutrient cycling and biological control, which are critical locally when considering the regional trend towards aridification and the existing pressures on water resources. Ecosystem functions loss and climate change impacts may lead to a shift in ecotone boundaries favouring the semiarid Caatinga vegetation. These results urge the implementation of ecosystem-based spatial planning, focusing on urban green infrastructure and restoration of natural habitats and their connectivity, to prevent further ecosystem service losses. Local estimates of ESV required to inform the suggested policy actions are identified.

POTENCIAL REGENERATIVO DE UMA FLORESTA ECOTONAL NA REGIÃO DO ALTO URUGUAI EM SANTA CATARINA

Objetivou-se avaliar o potencial regenerativo do componente arbóreo em uma área ecotonal entre Floresta Ombrófila Mista e Estacional Decidual, na região do Alto Uruguai, Santa Catarina. Para isso, foi realizada a caracterização florístico-estrutural do componente arbóreo regenerante em diferentes classes de tamanho e verificada a similaridade florística entre as classes e o componente adulto. Foram consideradas três classes para o componente regenerante: Classe 1, plantas com altura entre 0,2 e 1 m, Classe 2, plantas maiores que 1 m e até 3 m, e Classe 3, plantas maiores que 3 m e com DAP < 5,0 cm. Informações sobre o componente adulto para as mesmas unidades amostrais foram extraídas do banco de dados Laboratório de Dendrologia e Fitossociologia (LABDENDRO), da Universidade do Estado de Santa Catarina. Todas as espécies regenerantes foram classificadas em guildas de regeneração (pioneiras, climácicas exigentes em luz e climácicas tolerantes à sombra), a partir de revisão de literatura e observações de campo. Para todo o componente e para cada classe de tamanho, foram calculados os índices de diversidade de Shannon (H’), de equabilidade de Pielou (J) e os Índices de Regeneração Natural por Classe (RNC) e Total (RNT). As similaridades entre os componentes foram obtidas pelo Índice de Sorensen. Foi realizado um teste de qui-quadrado aplicado a uma tabela de contingência para verificar a existência de associação entre a distribuição dos indivíduos pertencentes a espécies de diferentes guildas de regeneração e a classe de tamanho. Foram amostrados 771 indivíduos regenerantes, distribuídos em 51 espécies, cujos valores de H’ e J foram, respectivamente, de 3,06 e 0,77. A espécie com maior RNT foi Nectandra megapotamica (Spreng.) Mez. A similaridade com o componente adulto variou entre 0,46 para a Classe 3 e 0,62 para a Classe 1. Em todas as classes de tamanho ocorreu a predominância de indivíduos de espécies classificadas como clímax exigentes em luz. Conclui-se que as espécies do componente adulto estão representadas, principalmente, na classe de menor tamanho, na qual se encontra a maior parte dos indivíduos amostrados.

<b>Floristic-structural relationships between Canga ferruginous tree communities and adjacent vegetation types

Our objective was to evaluate the floristic and structural relationships between Canga tree communities and other vegetation types inserted in the physiognomic units set, in order to test the hypothesis that these communities have unique characteristics due to their specific environmental conditions. For this, we compared the structural and floristic attributes of Canga vegetation with adjacent semideciduous seasonal forest, Savanna and ecotone areas, evaluating the similarity in its behavior. Our results demonstrate the existence of distinct relationships among vegetation types in relation to different perspectives, related to macro-scale environmental attributes and to the phytogeographic context. In general, Canga tree vegetation has its structure associated with open vegetation types, such as the Cerrado (Savanna) and its composition associated with forest vegetation types, constituted by a community with specific ecological characteristics. Our results suggest the presence of ferruginous soils as a factor that contributes to environmental and ecological heterogeneity in vegetation matrices.

Climbing plants of Porto Ferreira State Park, southeastern Brazil

Abstract A floristic survey of climbing plants was carried out in an ecotone area of seasonal semideciduous forest (SSF) and forested savanna (CER), in Porto Ferreira State Park (PFSP), Southeastern Brazil. We sampled the reproductive specimens every month during two periods, March 2010 to September 2011 and April and July 2015. The surveys were performed by the walking method, and the sampled individuals were classified by habit, climbing mechanism and dispersal mode. Overall, 109 species, belonging to 67 genera and 29 families, were recorded; 49 species occurred in both, 29 and 31 were exclusive to SSF and CER, respectively. Bignoniaceae and Malpighiaceae were the richest families, with 17 species, followed by Sapindaceae (12 species), Asteraceae and Apocynaceae (8 species each) and Fabaceae (6). The majority of climbers were lianas, twining and anemochoric species, corresponding to 70%, 47% and 66% of all samples, respectively. In this work, we added one new family and 14 species to the Cerrado’s list of climbing plants from São Paulo state, and 10 species to the Brazilian seasonal semideciduous forest’s list. Therefore, we contributed to the understanding of diversity of climbing plants in vegetation types poorly studied for this plant group, mainly in the Cerradão, wherein we found new records for several species.

A climate‐driven tree line position model in the White Mountains of California over the past six millennia

AbstractAimPosition of the alpine tree line ecotone around the globe corresponds to a growing season isotherm of approximately 6°C. Accordingly, tree lines are important indicators of Holocene global and regional environmental change. A central line of inquiry in tree line ecology is to better understand the mechanisms that dictate tree line position on the landscape, as well as the environmental conditions that cause upslope and downslope shifts in its position at centennial to millennial time‐scales. Here, we present a climate‐driven model to predict tree line position over the past 6,000 years.LocationSheep Mountain, located in the White Mountain Range of California, USA.Time period4750 bce to present.Major taxa studiedGreat Basin bristlecone pine (Pinus longaeva BK Bailey).MethodsWe use a climate‐driven tree line position model that utilizes a topoclimate raster surface of growing season average temperature to predict the spatial position and area of the alpine tree line ecotone across the mountain range. We then produce a time series of tree line position predictions at 500‐year intervals from 4750 bce to present, and compare the predictions to the growth dates and spatial locations of 61 remnant bristlecone pine samples from above modern tree line.ResultsThe model indicates that tree line position in the White Mountains, CA migrated downslope throughout the Holocene until approximately 750 ce, rebounded slightly upslope by 1250 ce, and has since likely remained stationary. Applying the model under present‐day climatic conditions suggests the current tree line at Sheep Mountain may be out of climatic equilibrium by up to 250 vertical metres in some places.ConclusionThe results support independent conclusions from global tree line analyses, underscore the temperature sensitivity of the tree line ecotone, and further develop our understanding of climate‐driven tree line dynamics.

SHORT-TERM IMPACT OF A HYDROELECTRIC POWER PLANT’S RESERVOIR ON THE TREE COMPONENT IN AN ECOTONAL AREA IN SANTA CATARINA

ABSTRACT This study was conducted in an ecotonal area between the Mixed Ombrophilous Forest (MOF) and the Deciduous Seasonal Forest (DSF) in Santa Catarina, Brazil, to identify the impact of the water reservoir of the Garibaldi hydroelectric power plant on the mortality and floristic-structural composition of the tree component in a riparian forest adjacent to it. One year after the reservoir water filling, 48 200 m2 plots were systematically allocated in three sectors: adjacent to the water reservoir, intermediate slope and upper slope. The tree species individuals with circumference at breast height (CBH) > 15.7 cm were identified and measured (CBH); dead individuals were quantified. The geographic coordinates of each plot were obtained. Species diversity was analyzed by Shannon and Pielou indexes and the floristic-structural organization was evaluated through phytosociological estimates, Non-Metric Multidimensional Scaling (NMDS) and Mantel test. Variations on mortality and floristic-structural organization regarding environmental sectors were tested with Generalized Linear Models (GLMs). 70 species have been found in the community with Shannon and Pielou values of 3.10 and 0.73, respectively. Dead individuals have shown the second highest importance value (9.59%) with the highest mortality in the lower sector (p < 0.05), which may be associated with its proximity to the water surface. The community organization has shown spatial structure; however, the NMDS and GLMs have shown no floristic-structural differentiation among sectors, probably on account of the short period of exposure to reservoir filling impacts.