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Evolutionary changes in organisms are directly observable, and they can occur rapidly in the presence of strong natural selection. Here, we present the "airport ecology" to describe the rapid evolution of animals. The pygmy grasshopper Tetrix japonica exhibits significant variations in pronotum color and markings and is a good model organism for "airport ecology." There are trade‐offs in black‐spot markings in the pygmy grasshoppers; although it helps in camouflaging and reducing predation pressure, it stimulates overheating, resulting in a reduction in mating opportunities and foraging success under high solar irradiance. Therefore, the frequency of black‐spotted morphs is lower at lower latitudes than at higher latitudes along a latitudinal cline. However, in an airport where predation pressure is reduced by the removal of predatory bird populations, we predict that the frequency of black‐spotted morphs of T. japonica will be lower in habitats without predators than in those with predators at the same latitude; this demonstrates the anthropogenic effect on T. japonica polymorphism. As suggested here, predator‐free environments such as airports are valuable for illustrating the effects of anthropogenic activity on animal evolution. These findings can be extended to several other species that are found around airports and are potentially preferred by avian predators in terms of not only rapid evolution of color polymorphism but also evolution of various life‐history traits. [ABSTRACT FROM AUTHOR]

In 2016, Ecological Research ( ER) celebrated its 30th anniversary. ER's goal is to be the leading ecological, evolutionary, and biodiversity journal in Asia. This article introduces the development of ER, improvements to its editorial system and their outcomes, and the strategies designed to achieve this goal. ER has already become a leading comprehensive and international publication as shown by statistical evidence and its strong editorial foundation. However, some members of the Ecological Society of Japan (ESJ) retain impressions of an old stereotype about ER. The discrepancy between the current status of the journal and its stereotype may explain why submissions from Japan remain static. A new article category for ER, Biodiversity in Asia, was created to encourage Asian studies. In addition, the Forum category is dedicated to promoting a broad understanding of the ESJ's various activities. To promote open science, the proportion of open access articles in the journal is increasing. The publication of Data papers has been accelerated to improve the public availability of excellent open data sets. ER symposia and seminars provide good opportunities for members to participate. ER financially supports the invitation of scientists internationally to facilitate research exchanges with other countries and consequently promotes the internationalization of the ESJ. The ESJ is open to the world's ecologists, and your participation in developing ER is welcome. [ABSTRACT FROM AUTHOR]

Biodiversity informatics is the application of informatics techniques to ecology and biodiversity sciences. The premise is utilizing natural history collections/data, such as specimens and biodiversity observations, with information and communication technology. During the past two decades, biodiversity informatics has improved dramatically and has been applied increasingly in ecology science. In this paper, I review biodiversity informatics for ecology with a particular focus on the treatment of data. First, I discuss the traditional perspective of data collection and its usage in the ecological community. Then, I provide an overview of the trajectory of changing perspectives of data treatment relative to developing biodiversity informatics (i.e., the infiltration of the data reuse and sharing concepts). Specifically, I discuss the significance of data reuse, which offers numerous benefits for research, and data sharing with their supporting mechanisms and case studies. Finally, I discuss potential future developments in biodiversity informatics relative to the field of ecology. [ABSTRACT FROM AUTHOR]

Human activities are having major impact on biogeochemical cycles and ecosystems worldwide. Rapid urbanization and changes in rural populations are affecting ecosystems in often-drastic ways. Ecologists are using long term monitoring and experimental studies to understand and to help mitigate the effects of these changes. The collection of 15 papers in this special volume “global changes in terrestrial ecosystems” describes some of these studies, particularly concentrating on effects on terrestrial ecosystems and landscapes, and demonstrating the importance of understanding the problems at both the multi-scale and international levels. [ABSTRACT FROM AUTHOR]

Studies of animal movements have been popularized for many large and shy species by the increasing use of radio telemetry methods (VHF and GPS technologies). Data are collected with high sampling frequency, and consist of successive observations of the position of an individual animal. The statistical analysis of such data poses several problems due to the lack of independence of successive observations. However, the statistical description of the temporal autocorrelation between successive steps is rarely performed by ecologists studying the patterns of animals movements. The aim of this paper is to warn ecologists against the consequences of failing to consider this aspect. We discuss the various issues related to analyzing autocorrelated data, and show how the exploratory analysis of autocorrelation can both reveal important biological insights and help to improve the accuracy of movement models. We suggest some tools that can be used to measure, test, and adjust for temporal autocorrelation. A short ecological illustration is presented. [ABSTRACT FROM AUTHOR]

Compared to conventional approaches, the integration of population size analysis with habitat suitability assessment on a large scale can provide more evidence to explain the mechanisms of habitat isolation and fragmentation, and thus make regional conservation plans. In this paper, we analyzed the habitat suitability for giant pandas in the Minshan Mountains, China, using the ecological-niche factor analysis (ENFA) method, and then evaluated the current conservation status of this endangered species. The results showed that (1) giant pandas were distributed in a narrow altitudinal range in which vegetation cover was dominated by coniferous forest, mixed coniferous and deciduous broadleaf forest, and deciduous broadleaf forest with scattered bamboo understory, and (2) roads and human settlements had strong negative effects on the panda habitat selection. According to habitat analysis, the total habitat area of giant panda in the Minshan Mountains was 953,173 ha, which was fragmented into 12 habitat units by major roads, rivers, and human settlements. The habitat of the mid-Minshan was less fragmentized, but was seriously fragmented in the north. The panda population size estimation showed that 676 individuals inhabited the study area, and 94.53% of them were in the mid-Minshan, but small panda populations less than 30 individuals inhabited the isolated and fragmented habitat patches in the north. The nature reserves in the Minshan Mountains have formed three conservation groups, which covered 41.26% of panda habitat and protected 70.71% of panda population of the study area, but there still exists two conservation gaps, and the connectivity among these reserves is still weak. Due to habitat isolation and extensive human disturbances, giant pandas in the north (i.e., Diebu, Zhouqu, and Wudou) are facing threats of local extinction. In order to protect pandas and their habitats in this area, some effective conservation approaches, such as establishing new reserves in gap areas, creating corridors among patches, and seasonally controlling traffic flux in key roads, should be implemented in the future to link these isolated habitats together. [ABSTRACT FROM AUTHOR]

A transplant experiment was conducted on a sandy beach to elucidate whether salt spray and sandblasting are the major factors inhibiting inland plants from becoming established on coastal sand dunes. Potted inland plants of Miscanthus sinensis and Imperata cylindrica var. koenigii were transplanted in two zones on the beach and in one area far inland from the beach. One zone on the beach (sea side) was located on a front dune that was occupied by native sand-dune plants; the other zone (land side) was located behind the sand dunes, where grassland comprised both sand-dune and inland species. To assess the condition of transplants, we measured changes in the canopy leaf area periodically at all sites. The final dry weight at each site was determined at the end of the experiment. Seasonal changes in sandblasting and salt spray intensities were evaluated periodically at the sites by measurement of the opaqueness of exposed transparent plastic sheets and the amount of sodium trapped in exposed filter papers, respectively. All transplants died in the sea-side zone, where both salt spray and sandblasting were most frequent and intense. The final dry weight was greatest at the inland site, which lacked salt spray and sandblasting. Although salt spray was intense in the land-side zone, the canopy leaf area decreased considerably only in seasons during which salt spray was accompanied by intense sandblasting. We concluded that sandblasting accompanied by salt spray is one of the main factors inhibiting the survival and growth of inland plants on coastal sand dunes. [ABSTRACT FROM AUTHOR]

Conservation biology needs to be concerned not just with exogenous threats to populations, but also with the changing nature of populations themselves. In a previous review paper, we highlighted evolution in contemporary time (years to decades) as a largely overlooked aspect of population responses to environmental perturbations. We argued that these responses might affect the fate of natural, managed and exotic populations. In the present review, we discuss issues that may limit the integration of contemporary evolution into conservation biology—with the intent that recognition of these limitations may foster research, discussion and resolution. In particular, we consider (1) alternative perceptions of “evolutionary” and “ecological” time, (2) the role of contemporary evolution as an ecological process, (3) fitness as a bridge between evolution and conservation, and (4) challenges faced by conservation strategies based on gene flow estimation or manipulation. We close by highlighting some situations in which current conservation approaches and contemporary evolution may require reconciliation. [ABSTRACT FROM AUTHOR]

In this paper, both the empirical and theoretical genetic aspects of human-mediated introgressive hybridization are reviewed in terms of their association with the breakdown of postzygotic isolating mechanisms. I also compare several simulation models with an ecological or genetic focus that are relevant to the prediction and risk assessment of genetic extinction due to hybridization. One barrier to devising comprehensive risk assessment frameworks is a lack of sufficient population genetic studies that associate introgressive hybridization with specific isolating mechanisms. A gametic model based on multilocus underdominant fitness is one of the best genetic models for introgressive hybridization because it explicitly incorporates the postzygotic isolating mechanism known as Dobzhansky–Muller genetic incompatibility. [ABSTRACT FROM AUTHOR]

Contemporary anthropogenic evolution is common. Biological invasions are an especially dynamic form of novel selection. This paper considers how native species evolve in response to biological invasions and the potential consequences of such evolution. Among numerous recent cases, the most widely reported instances are of phytophagous insects shifting onto introduced host plants. For example, our studies show that in North America and Australia, soapberry bugs evolved substantially after colonizing introduced hosts. Such cases permit close estimation of evolution’s direction and rate, and we have used cross-rearing studies of derived and ancestral-type populations to measure changes in reaction norms and performance tradeoffs. Different fitness traits have followed very different paths in evolving to their current phenotypic values. Our hybridization studies show that the genetic architecture of these adaptations involves a surprising degree of non-additive variation (epistasis, dominance). The importance of non-additive genetic variation in rapid evolution will be clarified as more studies take advantage of similar situations. As appreciation grows for the deep contemporary interplay of evolution and ecology, debate about qualitative terms describing evolution’s rate will become less relevant. From a conservation standpoint, contemporary evolution in native species presents challenges for ecologically appropriate and sustainable management. Evolving natives and invaders may reconfigure contemporary and future communities. Adaptive evolution may also enhance native communities’ capacity to control invasive populations. [ABSTRACT FROM AUTHOR]

Exhaustion of a natural resource stock may be a rational choice for an individual and/or a community, even if a sustainable use for the resource is feasible and the resource users are farsighted and well informed on the ecosystem. We identify conditions under which it is optimal not to sustain resource use. These conditions concern the discounting of future benefits, instability of a social system or ecosystem, nonconvexity of natural growth function, socio-psychological value of employment, and strategic interaction among resource users. The identification of these conditions can help design policies to prevent unsustainable patterns of resource use. [ABSTRACT FROM AUTHOR]

This paper presents a quantitative account of vegetation–soil environmental factor relationships in the Wangsuk stream (WS) and the Gwarim reservoir (GR) in Korea. Vegetation and the following soil variables were investigated in May, August and October 2004: pH, conductivity, water content, organic matter, total nitrogen content, NH4–N content, PO4–P content, total Ca, Mg, K, and Na content, extractable Ca, Mg, K and Na content, soil texture, distance from the channel, and elevation above water level. Species richness, diversity and ratio of hydrophyte occupation in WS were different from those in GR. Species richness was higher in WS, whereas the ratio of hydrophyte occupation was higher in GR. There were large temporal and spatial variations in plant distribution in the riparian and aquatic zones of WS but only slight variations in those of GR. These differences might have arisen from differences in flooding regime, distance from the stream channel related to elevation above water level, and soil properties such as soil texture and available nutrients. The median values of organic matter, total nitrogen, NH4–N, PO4–P and extractable Ca, Mg, K and Na contents in the soil were higher in GR than in WS. Sandy loam and loamy sand were common soil types in WS and clay loam and sandy clay loam in GR. Ten vegetation groups in WS and six in GR were identified using TWINSPAN. DCCA indicated that the distance from the stream channel was most strongly related to plant distribution and this reflected the spatial distribution of plant species in WS. In both WS and GR, NH4–N content in soil and soil texture were important factors for the distribution of species in May, August and October. Spatial and temporal heterogeneity of soil variables were related to species distribution. [ABSTRACT FROM AUTHOR]

Human domination of the Earth has resulted in dramatic changes to global and local patterns of biodiversity. Biodiversity is critical to human sustainability because it drives the ecosystem services that provide the core of our life-support system. As we, the human species, are the primary factor leading to the decline in biodiversity, we need detailed information about the biodiversity and species composition of specific locations in order to understand how different species contribute to ecosystem services and how humans can sustainably conserve and manage biodiversity. Taxonomy and ecology, two fundamental sciences that generate the knowledge about biodiversity, are associated with a number of limitations that prevent them from providing the information needed to fully understand the relevance of biodiversity in its entirety for human sustainability: (1) biodiversity conservation strategies that tend to be overly focused on research and policy on a global scale with little impact on local biodiversity; (2) the small knowledge base of extant global biodiversity; (3) a lack of much-needed site-specific data on the species composition of communities in human-dominated landscapes, which hinders ecosystem management and biodiversity conservation; (4) biodiversity studies with a lack of taxonomic precision; (5) a lack of taxonomic expertise and trained taxonomists; (6) a taxonomic bottleneck in biodiversity inventory and assessment; and (7) neglect of taxonomic resources and a lack of taxonomic service infrastructure for biodiversity science. These limitations are directly related to contemporary trends in research, conservation strategies, environmental stewardship, environmental education, sustainable development, and local site-specific conservation. Today’s biological knowledge is built on the known global biodiversity, which represents barely 20% of what is currently extant (commonly accepted estimate of 10 million species) on planet Earth. Much remains unexplored and unknown, particularly in hotspots regions of Africa, South Eastern Asia, and South and Central America, including many developing or underdeveloped countries, where localized biodiversity is scarcely studied or described. "Backyard biodiversity", defined as local biodiversity near human habitation, refers to the natural resources and capital for ecosystem services at the grassroots level, which urgently needs to be explored, documented, and conserved as it is the backbone of sustainable economic development in these countries. Beginning with early identification and documentation of local flora and fauna, taxonomy has documented global biodiversity and natural history based on the collection of "backyard biodiversity" specimens worldwide. However, this branch of science suffered a continuous decline in the latter half of the twentieth century, and has now reached a point of potential demise. At present there are very few professional taxonomists and trained local parataxonomists worldwide, while the need for, and demands on, taxonomic services by conservation and resource management communities are rapidly increasing. Systematic collections, the material basis of biodiversity information, have been neglected and abandoned, particularly at institutions of higher learning. Considering the rapid increase in the human population and urbanization, human sustainability requires new conceptual and practical approaches to refocusing and energizing the study of the biodiversity that is the core of natural resources for sustainable development and biotic capital for sustaining our life-support system. In this paper we aim to document and extrapolate the essence of biodiversity, discuss the state and nature of taxonomic demise, the trends of recent biodiversity studies, and suggest reasonable approaches to a biodiversity science to facilitate the expansion of global biodiversity knowledge and to create useful data on backyard biodiversity worldwide towards human sustainability. [ABSTRACT FROM AUTHOR]

Human-caused habitat destruction, the major cause of species diversity losses, can be classified into two basic types, instantaneous destruction and continuous destruction. Thus, a universal model should be established to simulate and forecast the effects of different kinds of habitat destruction on species diversity during different historical periods. In this paper, we explore a multi-time-scale n-species model to study and compare species responses to instantaneous and continuous destruction. We find that (1) under instantaneous destruction, there are two different mechanisms of species extinction: one is a time-delayed deterministic extinction of superior competitors in order from the best to the poorest; the other is the extinction in a short time of inferior competitors. The survivors will experience three phases: decline, adjustment, and equilibrium. (2) When the total amounts of habitat destruction for both instantaneous and continuous cases are equal, the oscillation amplitudes of species abundances under instantaneous destruction are much greater than under continuous destruction, especially for inferior competitors, which make inferior competitors under instantaneous destruction more prone to stochastic extinction. Therefore instantaneous destruction is more detrimental to the survival of inferior competitors. (3) Under continuous destruction with habitat eventually being destroyed completely, there also are two types of species extinction mechanisms: the first is extinction in order from the best competitors to the poorest before complete destruction; the second is collective extinction due to complete destruction. [ABSTRACT FROM AUTHOR]

The chemical fingerprinting of a plant demands the determination of a large number of elements at background level but also in polluted regions and in relation to other species. The most important stages of the development of plant fingerprints are mentioned in this paper and a short survey of the state of the art is presented. Examples on fingerprinting of lichens, mosses, Taraxacum officinale and Populus nigra‘Italica’ are presented. [ABSTRACT FROM AUTHOR]

Vegetation and land-use mosaics of shrub land, grassland, farmland and reforested land are characteristic for residential areas of the Wolong nature reserve in Sichuan province, southwest China. The patterns represent a stage in long-term human disturbance and natural secondary succession since deforestation. The aim of this paper was to elucidate the soil-land cover types, soil-slope position relationships on a typical disturbed slope in the humid mountainous region. Soils were taken from four typical land cover types (shrub land, grassland, farmland and reforested land) under four slope positions (upper slope, middle slope, lower slope, foot slope) to study the distribution of soil nutrients and moisture on the transect scales of the slope. To elucidate the influence of land-use and slope position on soil quality, two integrated quantitative indexes were developed to compare soil quality under different land-use types ( QI) and under different slope positions ( PI). The results showed shrub land had the highest QI value, while the QI of reforested land and farmland had lower values. Foot slopes and upper slopes had higher soil quality levels compared to middle slopes and lower slopes. The results indicated that on the slope scale shrub land had high soil quality levels. The results also suggested that in the area of China where the climate favors secondary succession, ‘leave nature as it is’ is a better choice than the policy ‘change farmland to forest land’. [ABSTRACT FROM AUTHOR]

A four-year study on the interactions between plants and seed-harvesting ants in a Mediterranean pasture is reviewed in this paper. As previously reported in many studies on plant–herbivore interactions, ant–plant relationships are also asymmetric; plants had a larger impact on herbivore dynamics than vice versa. However, the asymmetry did not refer to population dynamics but rather to animal foraging strategies. Ants did not exert a significant influence on vegetation dynamics in terms of plant abundance. The main constraints underlying vegetation change were self-regulation and rainfall. In contrast, the structural characteristics and abundance of vegetation had a significant impact on several important features of food harvesting by ants. This influence was not only associated with their feeding requirements but also with their foraging activities. [ABSTRACT FROM AUTHOR]

Asian dusts, yellow sand, or dust and sand storms (DSS) in Asian continent are the end products of desertification, which became a regional environmental problem being aggravated by time. It is closely related to an issue of sustainability in the region. As the desertification is caused not only by natural factors, such as the climate change, strong wind, and low precipitation, but also by rapidly increasing human activities, such as overgrazing, misuse of water resources, and irrational land use, it is urgent to make efforts to combat desertification in Asian continent including China. In this regard, it is necessary to consider socio-economic aspects as well as ecological aspects and, consequently, the project for the construction of a Demonstration Model Village for eco-environmental rehabilitation should be paid to a special attention. The authors deal with this regional issue in consideration of three Es, which are represented by ecology, economy, and environment in providing the perspectives in sound approach to the issue. As an approach to the issue of Asian dusts and desertification in Asian continent, this Eco-Village study provides one way forward. [ABSTRACT FROM AUTHOR]

The idea of the diversity–productivity relationship in ecology was originated by Charles Darwin more than 100 years ago and was highlighted by McNaughton in 1993. There have been extensive studies on this relationship, mostly conducted in grasslands. Many studies assert that a high level of biodiversity leads to high primary productivity, in accord with Darwin. However, these studies have mostly been done in grasslands (primary producer) and do not take into account effects from other trophic levels. The possibility remains that the positive diversity–production relationship does not hold in other types of ecological systems and that multitrophic effects influence and modify the relationship. In the present study, the diversity–productivity relationship is examined for freshwater foodwebs, including whole trophic compartments, by using indices of diversity and productivity more suitable for a whole systemic study on ecological systems. It seems that there are two trends in the relationship: productivity increases with the increase of diversity in ecosystems when diversity is small, and decreases with diversity in ecosystems when diversity is large. The first trend may be due to nutrient-limiting characteristics and the second trend may be due to photosynthetically active radiation–limiting characteristics. Also, both higher trophic and whole-systemic productivities are found to increase relative to primary productivity with the increase of diversity. Stability indices introduced previously, combined with the present results, reveal a positive correlation between relative productivity and stability in freshwater foodwebs, including all trophic compartments. [ABSTRACT FROM AUTHOR]

Understanding spatio-temporal patterns of grassland evapotranspiration (ET) and water use efficiency (WUE) in arid areas is important for livestock production and ecological conservation. Xinjiang, China, was used as an example in the Biome-BGC model to explore spatio-temporal patterns of grassland ET and WUE from 1979 to 2012 in arid areas. The ET ranked from high to low as follows: among seasons, summer (142.4 mm), spring (49.7 mm), autumn (45.9 mm) and winter (7.7 mm); among regions, the Tianshan Mountains (357.9 mm), northern Xinjiang (221.3 mm) and southern Xinjiang (183.2 mm); among grassland types, mid-mountain meadow (387.7 mm), swamp meadow (358.3 mm), typical grassland (343.9 mm), desert grassland (236.2 mm), alpine meadow (229.7 mm), and saline meadow (154.7 mm). The WUE ranked from high to low as follows: among seasons, summer (0.60 g C kg HO), autumn (0.48 g C kg HO) and spring (0.43 g C kg HO); among regions, northern Xinjiang (0.73 g C kg HO), the Tianshan Mountains (0.69 g C kg HO) and southern Xinjiang (0.26 g C kg HO); among grassland types, mid-mountain meadow (0.86 g C kg HO), typical grassland (0.84 g C kg HO), swamp meadow (0.77 g C kg HO), saline meadow (0.52 g C kg HO), alpine grassland (0.37 g C kg HO) and desert grassland (0.34 g C kg HO). In Xinjiang grasslands, the spatio-temporal ET patterns were more strongly influenced by precipitation than by temperature, whereas most high WUE values occurred when precipitation and temperature were relatively conducive to grass growth. [ABSTRACT FROM AUTHOR]

The article studies the relationships between biodiversity and ecosystem functioning. The spatial and temporal scales of the biodiversity examined vary widely among individual studies. A symposium was organized in which four researchers presented biodiversity studies carried out at different scales using different approaches.

Nitrogen (N) and phosphorus (P) are most commonly the limiting essential elements that affect the functioning of plants and ecosystems. However, their stoichiometry in relation to climatic variables and vegetation organization levels has not been comprehensively characterized. N and P concentrations were measured for 329 leaf samples collected at 132 sites along the 5000 km long China Grassland Transect that traverses the Inner Mongolian and Qinghai-Tibet Plateaus. The patterns of these measurements were analyzed with reference to climate factors, plant species, plant functional groups, grassland communities and grassland ecosystems. The aim was to explore whether geographical patterns of plant leaf elements are related to zonal climatic variables, and at which vegetation organization levels changes of plant leaf N and P stoichiometric characteristics and pattern occur. Results showed that interspecific differences of N and P concentrations were most significant for the three vegetation organization levels of species, community and ecosystem. Plant leaf N and P concentrations were higher, coefficients of variation of N and P lower, and N/P, C/N and C/P ratios were also lower for leaf samples from the cold high altitude Qinghai-Tibet Plateau than for those from the relatively lower altitude and warmer Inner Mongolian Plateau. Correlation of N and P for Inner Mongolian grassland was higher than that for the Qinghai-Tibet Plateau. The study indicates plant species are the most basic unit influencing plant stoichiometric geographic patterns, and that climatic variables affect leaf element concentrations mainly through their effect on changes of plant species composition of vegetation. [ABSTRACT FROM AUTHOR]

The alarm pheromones often released by animals under stressful situations seem to elicit behavioral changes in conspecifics, which in the appropriate context can be viewed as anti-predatory responses. However, the releasing of alarm pheromones associated with predatory events has not been demonstrated in mammals. In the current study with wild-caught Cabrera voles, we carried out experiments in the laboratory and in the field to assess the release of alarm pheromones in scent-marks during simulated predatory events and disclose their effects on conspecifics. We first conducted an assay wherein voles where let to scent-mark a clean substrate in the absence of disturbance (control) and under the simulation of predatory events. Contrarily to the control, no fecal boli were released and the area marked with urine was significantly larger during the predatory simulation. In a subsequent assay, we assessed the voles' preference between urine-marks released under predatory simulation and in control conditions. Voles showed a significant preference by control substrates. Finally, a third assay was carried out in the vole's habitat wherein the individual activity was monitored by radio-tracking before and after placement of urine-marks obtained during the conditions described above. The vole's activity was only reduced near the urine-marks released during the simulated predatory events. The results suggest that: (1) during predatory attempts, Cabrera voles release an alarm pheromone in their urine-marks; (2) the putative alarm pheromone reduces the voles' activity in the surroundings of the marked area; (3) the putative alarm pheromone persists in the field affecting conspecifics' activity for several days. [ABSTRACT FROM AUTHOR]

Human-induced nitrogen (N) enrichment is impacting the structure and function of grassland ecosystems, although few studies have been conducted in arid and semi-arid ecosystems under field conditions. Here, a 4-year multi-level N addition experiment under ambient precipitation in a typical temperate desert steppe in arid regions of China was designed to evaluate the impact of N enrichment on the herbaceous vegetation community in desert ecosystems. The results showed that species richness declined in response to N addition during all 4 years, while aboveground biomass increased in the relatively wet year (2007) and decreased in the relatively dry years (2008-2010) according to N addition level, as compared to the control. Plant community composition differed among plant functional groups (PFGs) based on added N. Perennial grasses (PG) benefited more compared with annuals and perennial forbs (PF) from N enrichment in terms of biomass production under conditions of high precipitation in 2007. In relatively dry years, biomass production of all PFGs was strictly dependent on inter- and intra-annual precipitation, which led PG to dominate in 2008 (with a dry spring) and PF to dominate in 2009 and 2010. Our results demonstrate that the impact of N enrichment on the herbaceous vegetation community in desert steppes may be strongly dependent on natural precipitation patterns characterized by shifts in plant community composition, particularly in terms of biomass production. [ABSTRACT FROM AUTHOR]

Many studies have been conducted on ecosystem services and double counting is a frequent problem that causes uncertainty and poor reliability of estimating the value of ecosystem services. By referring to previous studies of ecosystem service valuation, our research has identified the basic causes of double counting. These include ambiguous definitions and inconsistent classifications of ecosystem services, poor understanding of ecosystem complexity, inadequate recognition of exclusiveness and complementarities of individual ecosystem services, spatio-temporal scale dependence of ecosystem services, and overlap and lack of cross-referencing between ecosystem service valuation methods. Measures for reducing double counting in ecosystem service valuation are proposed as follow: (1) identifying the spatio-temporal scales of ecosystem services; (2) valuing the final benefits obtained from ecosystem services; (3) establishing consistent classification systems for ecosystem services; and (4) selecting valuation methods appropriate for the study context. [ABSTRACT FROM AUTHOR]

Reproductive rate is a key demographic parameter of life history and population ecology. In traditional population-ecology studies of small mammals, this and other vital rates are inferred from capture-mark-recapture (CMR) data. However, CMR assumes that immigrants at first capture can be distinguished from unmarked locally born offspring, an assumption not always met. We verified CMR estimates of locally born red squirrel ( Sciurus vulgaris) offspring as a measure of reproductive rate, with candidate offspring (CO)–candidate parent (mothers, CPs) assignment by CERVUS, using ten DNA microsatellite loci. Seventy-two of 122 candidate offspring (59%) were assigned to 52 of 125 CPs in six populations. Estimates of mean litter size were 1.5 young (range 1–3). The 50 CO (41%) not assigned to a reproducing female in the study site were considered immigrants. Parentage assignment also provided evidence of dispersal between two of our sites. Overall, CMR and CERVUS agreed in 77% of cases. Considering only the 55 juveniles determined as locally born by CMR, 50 (91%) were also assigned as local offspring with CERVUS. The main discrepancy between the two methods was that 22 subadult squirrels classified immigrants by CMR, were assigned by CERVUS to females which had reproduced in our sites. It is concluded that although in our study system agreement between CMR and CERVUS in determining local offspring was high, using genetic parentage assignment helped to correctly classify some subadults, considered immigrants by CMR, as locally born. Hence, in large-scale demographic studies, combining CMR with parentage assignment will allow more precise estimates of reproduction and dispersal. [ABSTRACT FROM AUTHOR]

Habitat selection may reflect the location of the home ranges or the allocation of shelter and foraging sites within a given habitat. We studied seasonal patterns of habitat use by Akodon azarae and Calomys laucha at two spatial scales: between maize fields and their weedy edges (macrohabitats), and associations of rodents captures with vegetation variables at the trap site level (microhabitats). We evaluated if the different habitat uses were related to disturbances generated by practices associated to maize cycle. A. azarae used mainly field edges, but it showed an increased use of maize fields when the crop reached maturity in summer. Contrarily, C. laucha used maize fields in a higher proportion than edges in all seasons. C. laucha was more influenced by microhabitat characteristics than A. azarae. C. laucha was present in sites with abundant dicot weeds when maize was growing up, while it was associated to sites with weeds with scarce cover in stubble maize fields. Before harvesting, both species were segregated at the microscale within maize fields. A. azarae was related to sites with high availability of green plant cover and C. laucha occupied low-quality sites, probably attributed to differences in their diets. We conclude that the pattern of habitat use by both species is best predicted at the macrohabitat scale, and when they are impoverished and present internal heterogeneity, there is selection at microhabitat scale of those better sites. While A. azarae responds to changes in vegetation cover and habitat structure associated to agricultural practices, C. laucha uses cropfields in an opportunistic way, affected by interspecific competition. [ABSTRACT FROM AUTHOR]

Pulses of water availability characterize semiarid and arid ecosystems. Most precipitation events in these ecosystems are small (≤10 mm), but can stimulate carbon flux. The large proportion of carbon stored belowground and small carbon inputs create the potential for these small precipitation events to have large effects on carbon cycling. Land-use change can modify these effects through alteration of the biota and soil resources. The goal of our research was to determine how small precipitation events (2, 5, and 10 mm) affected the dynamics of soil carbon flux and water loss in previously cultivated Conservation Reserve Program (CRP) fields and undisturbed shortgrass steppe. Total carbon loss and duration of elevated carbon flux increased as event size increased in all field types. Time since cultivation increased in importance for carbon flux as event size increased. A comparison of water loss rates to carbon flux suggests that water is limiting to carbon flux for the smallest events, but is less limiting for events above 5 mm. We also describe how water availability interacts with temperature in controlling carbon flux rate. We conclude that small precipitation events have the potential for large short-term losses of carbon in the shortgrass steppe. [ABSTRACT FROM AUTHOR]

Much of the primary vegetation at low altitudes has been greatly altered or destroyed by a long history of human activities. This is particularly true in eastern China, where low-altitude areas are now dominated by secondary forests or plantations. Altitudinal vegetation zonation of this region is often based on these secondary forests, resulting in seral vegetation with an obscure zonal sequence. Here, we deduced the potential climax vegetation according to the regeneration patterns of the dominant species of the secondary forests at low altitudes (below 1,000 m a.s.l.) on Mt. Tianmu (1,506 m a.s.l., 30°18′30″–30°21′37″N, 119°24′11″–119°27′11″E). Based on the potential climax vegetation combined with the floristic composition and community structure, three vegetation zones were identified, viz: (1) evergreen broad-leaved forest zone (400–950 m a.s.l.); (2) evergreen and deciduous broad-leaved mixed forest zone (950–1,100 m a.s.l.); (3) deciduous broad-leaved forest zone (1,100–1,506 m a.s.l.). The altitudinal vegetation zones identified in this study correspond with the thermal conditions on Mt. Tianmu. The distribution of vegetation on Mt. Tianmu was limited by lower temperatures in winter, and the altitudinal thermal vegetation zones on this mountain were more similar to the thermal vegetation of Japan than to that of China. The vertical distributions and roles of conifers were different between the eastern and the western regions along 30°N latitude in humid East Asia. Cryptomeria fortunei formed the emergent layer, towering above the broad-leaved canopy at middle altitudes as C. japonica on Yakushima, but disappeared at high altitudes with hydrothermal limitation on Mt. Tianmu. [ABSTRACT FROM AUTHOR]

This study evaluates the effect of water availability on tolerance and resistance to the aphid Chaitophorus leucomelas by clones of the double hybrid [( Populus trichocarpa × P. maximowiczii Henry) × ( P. trichocarpa × P. maximowiczii)] (TM × TM), a hybrid that was previously described as resistant to this aphid. In a 2 × 2 experimental design implemented in a nursery, we were able to assess growth (branch length, number of leaves and branch base diameter) in saplings reared in the natural presence of aphids (natural aphid damage) and aphid-controlled conditions (undamaged) under both well-watered and drought stress conditions. We found that resistance was reduced under drought stress conditions, while tolerance in branch length was increased. Cost of resistance was detected as clones displaying higher tolerance grew less in the absence of aphids, whereas no evidence of costs associated with tolerance was found in any of the growth traits measured, A genetic trade-off between tolerance and resistance was detected, but this trade-off was not affected by water availability. Considering the average response of both defence strategies, well-watered trees seem to allocate more resources to resistance than to tolerance, whereas drought-stressed trees allocate more to tolerance than to resistance. This suggests that tolerance would imply a lower cost than resistance, and the shift to either strategy could be modulated by resource availability. [ABSTRACT FROM AUTHOR]

Relationships between microhabitat variables; understory light conditions in summer and winter, altitude, slope inclination and topographic categories (valley, ridge, and slope) and the distribution of Aucuba japonica Thunb. (Cornaceae), a common understory shrub species in Japan were examined using non-contagious 66, 20 × 20 m2 quadrats. The Morishita’s Iδ suggested that A. japonica distributions were strongly heterogeneous among the quadrats. Therefore positive spatial autocorrelation of A. japonica at a within-quadrat level (≤20 m) was obvious. Moran’s I statistics showed a significant positive spatial autocorrelation in A. japonica abundance within the distance shorter than 60 m. But the partial Mantel tests suggested that the mass effect from neighboring quadrats would little explain A. japonica abundance in a quadrat. The partial Mantel tests also clearly showed that A. japonica distributions were strongly structured by topography and understory light conditions. Using Monte Carlo randomization tests, we found that A. japonica was aggregately distributed in quadrats in valley which were covered by deciduous canopies. Better understory light conditions in winter together with valley edaphic conditions may increase the abundance of A. japonica there. It is concluded that habitat niche specialization is important in structuring distribution of A. japonica in this forest community. [ABSTRACT FROM AUTHOR]

Spatial synchrony is common, and its influences and causes have attracted the interest of ecologists. Spatially correlated environmental noise, dispersal, and trophic interactions have been considered as the causes of spatial synchrony. In this study, we developed a spatially structured population model, which is described by coupled-map lattices. Our recent investigation showed that trophic correlation of environmental noise was another important factor that affects spatial synchrony. As a supplement, we considered the influence of the color of the environmental noise on the spatial synchrony in this study. The noise color refers to the temporal correlation in the time series data of the noise, and is expressed as the degree of (first-order) autocorrelation for autoregressive noise. Patterns of spatial synchrony were considered for stable, periodic (quasi-periodic), and chaotic population dynamics. Numerical simulations verified that the color of the environmental noise is another mechanism that causes spatial synchrony. Generally, the effect of the color of the noise on the synchrony is dependent on the type of dynamics (stable, cyclic, chaotic) present in the population. For cyclic dynamics, simulation results clearly demonstrate that reddened noise has higher synchrony than white noise. The importance of our research is that it enriches the theory of potential causes of spatial synchrony. [ABSTRACT FROM AUTHOR]

Predators display functional responses to variation in prey availability that result in dietary distinction at different spatial scales. Such differentiation can be enhanced when human-induced changes in land use increase spatial heterogeneity in prey availability. This has been recorded for canids, but available information is skewed to regional scales. Further, though human activities have strongly altered neotropical biomes, knowledge about small-scale dietary differentiation of canids come mainly from holartic species. Thus, we quantified variability in the diet of a ubiquitous South American canid species (i.e., the pampas fox, Pseudalopex gymnocercus) over a relatively small area of grasslands in Argentina, comparing its diet at three close sampling sites varying in human disturbance. We found that small-scale dietary differentiation was influenced by human-induced habitat modifications, both directly by local subsidizing of introduced prey (e.g., livestock carrion and hares) and indirectly by altering the availability of native prey. Overall, pampas foxes seemed to be highly flexible in their trophic ecology, being able to cope with marked habitat alterations and likely benefiting from food cross-subsidizing from agricultural landscape to protected grassland relicts. This has implications for management and conservation purposes, and highlights the importance of quantifying variability in foraging behavior of carnivores over small spatial scales. [ABSTRACT FROM AUTHOR]