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Currently the temperature humidity index (THI) is a common method of evaluating the risk of heat stress in cows by employing climatic parameters. However, the THI is a general and indirect indicator that fails to consider individual cows. Various studies have used animal-related parameters to account for the heat load of individual cows. This review provides an overview of different heat stress indicators that have been used in the past 10 years with a focus on animal-related and non-invasive indicators. These indicators are reviewed with regard to their potential for quantifying individual heat loads in ongoing and future studies of dairy cows. The review is divided into sections covering physiological, behavioural and performance indicators. Parameters that appear to be suitable for assessing the individual stress loads of dairy cows include respiration rate and body temperature, whereas losses in milk yield are more a consequence of heat stress than an indicator. Using activity and feeding behaviour as an indicator of heat stress may depend on the cows' physiological state. However, no thresholds for animal-related indicators employed as signs of heat load can be found in the literature. In contrast, thresholds for THI levels are described above which changes in cows’ physiology and behaviour are detectable under heat stress. In conclusion, the development and use of non-invasive sensors should focus on physiological indicators, and further studies are needed to determine the thresholds for these indicators.

The aim of this study was to evaluate the effects of evaporative cooling at two different frequencies per day on the respiration rate (RR) of lactating dairy cows, considering cow-related factors. Twenty multiparous Israeli Holstein dairy cows housed in a naturally ventilated cowshed were divided randomly into two treatment groups. The cows of both groups were exposed to 3 or 8 cooling sessions per day (3xcool vs. 8xcool, respectively). The RR was observed hourly, with a maximum of 12 measurements per day. Body posture (standing vs. lying) was simultaneously documented. Milk yield was recorded daily. Coat color was determined from a digital photograph. The RR of standing and lying cows was lower in the 8xcool group (60.2 and 51.6 breaths per min (bpm), respectively) than in the 3xcool group (73.1 and 65.6 bpm, respectively). For each increment of five kilograms of milk produced, RR increased by one bpm, and the RR of cows in early days in milk (DIM) was 12.3 bpm higher than that of cows in late DIM. In conclusion, eight cooling sessions per day instead of three lead to a RR abatement in heat-stressed cows under hot conditions, and cow-related factors directly impact the RR during heat stress assessment.

Forest and landscape restoration is a promising strategy for improving water, energy and food securities. We advocate that ‘forest security’ should form a fourth, foundational dimension of a novel water, energy, food and forest security nexus framework. Key principles of this new framework support an integrated role of forests in sustainable development, and engagement of local communities in nature-based solutions, particularly in the Global South. We believe that this new approach can help to accelerate the pace and magnitude of changes needed for achieving the United Nations Sustainable Development Goals. The water–energy–food nexus has provided a framework for comprehensive analysis, but this Perspective argues for adding forest studies to better integrate the needs and ecosystems of smallholders, especially in the Global South.

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2020 Submitted by Sofia Amador (sofiamador@fm.ul.pt) on 2021-05-27T09:23:21Z No. of bitstreams: 1 MariaIRocha.pdf: 813857 bytes, checksum: f74bc18422cd048dbb646a79a63a6d80 (MD5) Made available in DSpace on 2021-05-27T11:15:25Z (GMT). No. of bitstreams: 1 MariaIRocha.pdf: 813857 bytes, checksum: f74bc18422cd048dbb646a79a63a6d80 (MD5) Previous issue date: 2020-07-09

Technological progress enables individual cow's temperatures to be measured in real time, using a bolus sensor inserted into the rumen (reticulorumen). However, current cooling systems often work at a constant schedule based on the ambient temperature and not on monitoring the animal itself. This study hypothesized that tailoring the cooling management to the cow's thermal reaction can mitigate heat stress. We propose a dynamic cooling system based on in vivo temperature sensors (boluses). Thus, cooling can be activated as needed and is thus most efficacious. A total of 30 lactating cows were randomly assigned to one of two groups; the groups received two different evaporative cooling regimes. A control group received cooling sessions on a preset time-based schedule, the method commonly used in farms; and an experimental group, which received the sensor-based (SB) cooling regime. Sensor-based was changed weekly according to the cow's reaction, as reflected in the changes in body temperatures from the previous week, as measured by reticulorumen boluses. The two treatment groups of cows had similar milk yields (44.7 kg/d), but those in the experimental group had higher milk fat (3.65 vs 3.43%), higher milk protein (3.23 vs 3.13%), higher energy corrected milk (ECM, 42.84 vs 41.48 kg/d), higher fat corrected milk 4%; (42.76 vs 41.34 kg/d), and shorter heat stress duration (5.03 vs 9.46 h/day) comparing to the control. Dry matter intake was higher in the experimental group. Daily visits to the feed trough were less frequent, with each visit lasting longer. The sensor-based cooling regime may be an effective tool to detect and ease heat stress in high-producing dairy cows during transitional seasons when heat load can become severe in arid and semi-arid zones.

There is strong upswing in conservation and restoration efforts in Latin America (LA), particularly in the recent decades after several countries have committed to international agreements such as the Aichi targets of the Convention on Biological Diversity, Initiative 20×20, and the Bonn Challenge. To fulfill these agreements, the practice of ecological restoration has to be defined based on ecological knowledge, but also on the specific social, economic, and legal aspects of each country in the region. Here, we give some examples about the national understanding of ecological restoration in 10 countries of LA. We identify difficulties and opportunities to define restoration priorities and needs, and discuss some approaches to cope with economic constraints and agreements, including the potential role of restoration networks in this process. On the basis of the socioecological complexity of these countries and the expectations they have in relation to restoration, we proposed four approaches to guide restoration practice and policy in the region: (1) including biodiversity and ecosystem services approach into ecosystem restoration initiatives; (2) promoting restoration in their frequently human-modified landscapes; (3) accounting for cost–benefit trade-offs; and (4) assembling “horizontal” communication frameworks. These approaches should be based at national levels, but adapted to local-regional levels, in a bottom-up perspective. We consider that national and international restoration networks in the region can help to overcome difficulties, fostering a solid scientific community, helping to develop national approaches that better match the specific conditions of each country and enhancing communication among different groups of stakeholders.

Achieving ambitious global restoration commitments is a huge challenge. The Atlantic Forest Restoration Pact, created in 2009 as a movement to restore 15 Mha of degraded/deforested lands by 2050, pledged 1 Mha towards the 2020 Bonn Challenge. We documented the restoration of an estimated 673,510–740,555 ha of native forests from 2011 to 2015 in the Atlantic Forest, and expect that a total of 1.35–1.48 Mha will be under recovery by 2020. The Pact is one of the first Brazilian restoration initiatives to monitor an international restoration commitment and to demonstrate that ambitious targets can be reached. Part of this success in large-scale restoration is related to three main Pact activities: (i) development of restoration governance, communication and articulation; (ii) promotion of strategies to influence public policies; and (iii) establishment of restoration monitoring systems. The experience and lessons learned by the Pact could inspire and inform other restoration initiatives worldwide.

[EN] In the last decades, a global warming trend was observed. Along with the temperature increase, modifications in the humidity and wind regime amplify the regional and local impacts on livestock husbandry. Direct impacts include the occurrence of climatic stress conditions. In Europe, cows are economically highly relevant and are mainly kept in naturally ventilated buildings that are most susceptible to climate change. The high-yielding cows are particularly vulnerable to heat stress. Modifications in housing management are the main measures taken to improve the ability of livestock to cope with these conditions. Measures are typically taken in direct reaction to uncomfortable conditions instead of in anticipation of a long-term risk for climatic stress. Measures that balance welfare, environmental and economic issues are barely investigated in the context of climate change and are thus almost not available for commercial farms. Quantitative analysis of the climate change impacts on animal welfare and linked economic and environmental factors is rare. Therefore, we used a numerical modeling approach to estimate the future heat stress risk in such dairy cattle husbandry systems. The indoor climate was monitored inside three reference barns in central Europe and the Mediterranean regions. An artificial neuronal network (ANN) was trained to relate the outdoor weather conditions provided by official meteorological weather stations to the measured indoor microclimate. Subsequently, this ANN model was driven by an ensemble of regional climate model projections with three different greenhouse gas concentration scenarios. For the evaluation of the heat stress risk, we considered the number and duration of heat stress events. Based on the changes in the heat stress events, various economic and environmental impacts were estimated. The impacts of the projected increase in heat stress risk varied among the barns due to different locations and designs as well as the anticipated climate change (considering different climate models and future greenhouse gas concentrations). There was an overall increasing trend in number and duration of heat stress events. At the end of the century, the number of annual stress events can be expected to increase by up to 2000, while the average duration of the events increases by up to 22 h compared to the end of the last century. This implies strong impacts on economics, environment and animal welfare and an urgent need for mid-term adaptation strategies. We anticipated that up to one-tenth of all hours of a year, correspondingly one-third of all days, will be classified as critical heat stress conditions. Due to heat stress, milk yield may decrease by about 2.8 % relative to the present European milk yield, and farmers may expect financial losses in the summer season of about 5.4 % of their monthly income. In addition, an increasing demand for emission reduction measures must be expected, as an emission increase of about 16 Gg of ammonia and 0.1 Gg of methane per year can be expected under the anticipated heat stress conditions. The cattle respiration rate increases by up to 60 %, and the standing time may be prolonged by 1 h. This causes health issues and increases the probability of medical treatments. The various impacts imply feedback loops in the climate system which are presently underexplored. Hence, future in-depth studies on the different impacts and adaptation options at different stress levels are highly recommended., This research has been supported by the German Federal Ministry of Food and Agriculture (BMEL) through the Federal Office for Agriculture and Food (BLE) (grant nos. 2814ERA02C and 2814ERA03C), the Instituto Nacional de Investigacion Tecnologia Agraria y Alimentaria (INIA) (grant no. 618105), the Basque Government (grant no. BERC 2018-2021), the Spanish Ministry of Economy, Industry and Competitiveness MINECO (grant nos. MDM-2017-0714, FJCI-2016-30263, and RYC-2017-22143), and the Innovation Foundation Denmark (grant no. 4215-00004B).

Tropical forests have been rapidly converted into human-modified landscapes but the effects of such conversion on community spatial organization have been rarely addressed. In this paper, we examine to what extent the spatial reconfiguration of tropical landscapes alters plant trait distributions and the spatial organization of tree assemblages. A set of 117 tree species and 1422 individuals (≥10 cm DBH) inhabiting a fragmented Atlantic forest landscape in Brazil were assigned into categories of both vegetative and reproductive life-history traits, and matrices of trait frequencies were correlated to four spatial patch metrics via the concepts of trait-convergent, trait-divergent assembly pattern, and measures of functional richness, evenness, and diversity. Life form and seed dispersal syndrome exhibited the highest and significant degrees of trait-convergence related to connectivity and patch size gradients, respectively. Trait divergence based on seed dispersal syndrome and regeneration strategy emerged as well, particularly in response to patch area and connectivity. Finally, some functional diversity (multiple-traits) measures correlated with either a particular patch metric or species richness. Our results suggest that the spatial distribution of life-history traits and strategies exhibited by tree species correlate with spatial patch metrics, supporting the notion that human disturbances result in new environmental gradients able to spatially reorganize and restructure tree assemblages at broad spatial scales into human-modified landscapes.

The severity of heat stress conditions in high-yielding dairy cows is currently underestimated. The present study aimed to determine the heat load threshold of the temperature-humidity index (THI) on physiological parameters of lactating Holstein-Friesian cows under a continental climatic zone in Germany. Physiological parameter measurements, such as respiration rate (RR), measured hourly, and heart rate (HR) and rectal temperature (RT), both measured twice daily, were performed in a total of 139 multiparous cows on three randomly chosen measurement days per week. In addition, the ambient temperature and relative humidity of the barn were recorded every 5 min to calculate the current THI. The physiological parameter data were linked to the THI, and the heat load thresholds were determined using the broken-stick model. The heat load duration effect of each physiological parameter was obtained by regression analysis. Considering the increases in the physiological parameters, our study provided reliable data to determine heat load thresholds for lactating high-yielding dairy cows in a moderate climatic zone. The heat load threshold could be determined for RR in standing cows (THI = 70) and lying cows (THI = 65) and for HR (THI = 72) and RT (THI = 70) in standing cows. The heat load duration also demonstrated a significant effect on the increases in physiological parameters among dairy cows. In particular, the present study enabled a strategy to be devised to initiate heat mitigation in high-yielding dairy cows when they are exposed to THIs above 65.

Introduction Projected temperature rise in the upcoming years due to climate change has increased interest in studying the effects of heat stress in dairy cows. Environmental indices are commonly used for detecting heat stress, but have been used mainly in studies focused on the productivity-related effects of heat stress. The welfare approach involves identifying physiological and behavioural measurements so as to start heat stress mitigation protocols before the appearance of impending severe health or production issues. Therefore, there is growing interest in studying the effects of heat stress on welfare. This systematic review seeks to summarise the animal-based responses to heat stress (physiological and behavioural, excluding productivity) that have been used in scientific literature. Methods Using systematic review guidelines set by PRISMA, research articles were identified, screened and summarised based on inclusion criteria for physiology and behaviour, excluding productivity, for animal-based resilience indicators. 129 published articles were reviewed to determine which animal-based indicators for heat stress were most frequently used in dairy cows. Results The articles considered report at least 212 different animal-based indicators that can be aggregated into body temperature, feeding, physiological response, resting, drinking, grazing and pasture-related behaviour, reactions to heat management and others. The most common physiological animal-based indicators are rectal temperature, respiration rate and dry matter intake, while the most common behavioural indicators are time spent lying, standing and feeding. Conclusion Although body temperature and respiration rate are the animal-based indicators most frequently used to assess heat stress in dairy cattle, when choosing an animal-based indicator for detecting heat stress using scientific literature to establish thresholds, characteristics that influence the scale of the response and the definition of heat stress must be taken into account, e.g. breed, lactation stage, milk yield, system type, climate region, bedding type, diet and cooling management strategies. © 2018 Galan*E.*Elena et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. E.G., H.L. and S.P. were funded by the OPTIBARN Project through the research grant 618105 FACCE Era Net Plus – Food Security, Agriculture, Climate Change ERA-NET plus –JPI). P.L. was funded by the People Programme (Marie Curie Actions) of the Seventh Fram

This study provides an approximation of the potential impact of fuelwood harvesting in one of the most threatened tropical biodiversity conservation hotspots, the northern portion of the Brazilian Atlantic Forest. We test the relationship between fuelwood consumption and per capita income for 270 households distributed over 7 rural settlements. In general 76% of the households use fuelwood regularly and consume on average 686 kg/person/year of tree biomass, poorer people, however, consume 961 kg/person/year. Harvesting is concentrated to a few early successional species. Yet, annual rural population demand from 210 municipalities may reach 303,793 tons, equivalent to 1.2 to 2.1 thousand hectares of tropical forest. Fuelwood harvesting cannot be ignored as a major and chronic source of forest degradation in highly fragmented and densely populated landscapes and conciliating biodiversity conservation with poverty amelioration is an urgent task.

Ongoing conversion of tropical forests makes it urgent to invest in ecological restoration on grand scales in order to promote biodiversity conservation and ecosystem services. The 4-year old Atlantic Forest Restoration Pact (AFRP) aims to restore 15,000,000 ha of tropical forest in 40 years. The approaches and lessons learned appear transferable, and could help achieve the global restoration targets. Fundamental prerequisites for success include: effective technology undergoing continuous improvement, ongoing teaching, outreach and capacity-building efforts, presence of local intelligentsia, maintaining a clear and transparent legal environment, and presence of effective economic instruments and incentives for landowners. These prerequisites can be achieved by expanding and strengthening the network of stakeholders both in public and private forums that must be aware of macro-economic and social/cultural shifts and trends which may provide opportunities and impose constraints to further restoration activities. Finally, environmental regulations imposing habitat protection and restoration are usually beyond individual land-owners’ possibilities and level of interest. Therefore, forest restoration, even in a biodiversity hotspot, must be approached as a potentially sustainable economic activity. Otherwise, private landowners, and most other stakeholders, will not persevere.

Brazil is the world largest producer of sugarcane ethanol, an alternative to gasoline. Large players, including international oil companies, are aware of the potential of Brazilian ethanol and are investing in the production and expansion of sugarcane plantations in the country. The growing ethanol market imposes some conservation challenges on Brazil to meet the increasing demand. The market points out to an expansion of sugarcane crops, but this can be extremely harmful to the remaining biodiversity of the Brazilian Atlantic Forest. The impact of such expansion will be more severe in the states of Alagoas, Pernambuco, Paraíba and Rio Grande do Norte, the second largest sugar-ethanol production region, and one of the most globally threatened areas of tropical forest (only 12% left, ∼ 1% legally protected). There, most forest fragments are smaller than 100 ha and several endemic species are on the verge of extinction. Here we advocate that instead of expanding plantations, increasing crop productivity should be the more logical and environment-friendly solution for that region. Further, we indicate that the current challenge is to increase the number of sugar and ethanol companies following best management practices and to turn these programs into a real opportunity to restore the biodiversity and environmental services of an ecosystems in eminent collapse. We urge that companies should move one step further and, at least, guarantee the protection of the habitats that go beyond the protection area imposed by the current environmental law.

Habitat fragmentation imposes profound impacts on the tropical forest microclimate, but the microclimatic configuration of isolated forest patches and its implications for biodiversity persistence and habitat management are not clear. In this study we assessed a set of 10 aged (> 80 years) fragments (3.0 – 3,500 ha in size) of the Atlantic forest to examine to what extent fragment microclimatic attributes are correlated with distance to the nearest edge as frequently proposed in the literature. We used 129 sampling points and took a total of 516 measures of air temperature and humidity, vapor pressure deficit and light incidence to characterize the microclimate of forest fragments in terms of their relative deviation from the surrounding matrix. Fragments as a whole presented strong internal variation and strongly differed from the microclimate exhibited by the open matrix of sugar-cane fields. Distance to nearest edge, percentage of forest cover around the measurement point, percentage of edge-affected area, and geographical orientation of the nearest edge all proved to have minor effects on the microclimate of forest fragments. Conversely, we identified percentage of forest cover and fragment area as the most significant explanatory variables driving their microclimatic configuration: as forest cover increases at landscape scale, forest microclimate deviates less from the open matrix (a forest-mediated matrix buffering). Our results suggest that microclimatic conditions are spatially complex, as they do not correlate with the distance to the nearest forest edges; rather, they are driven by a forest-mediated buffering of the surrounding matrix that minimizes heat and humidity exchanges between forest and non-forest habitats, thus shaping the microclimatic signature of isolated forest fragments.

Much of the ecological alteration faced by human-modified Neotropical forests can be assigned to edge effects, including the proliferation of some voracious herbivores such as leaf-cutting ants. However, the underlying mechanisms/impacts of tropical forest edge on herbivores performance and their foraging behaviour (e.g. dietary diversity) have rarely been investigated. The goal of this study was, therefore, to determine whether and how the annual diet (i.e. species richness, diversity and the relative proportion of pioneer versus non-pioneer species of plant materials) of Atta cephalotes colonies differs in the forest edge versus the interior zone of a large remnant of Atlantic forest in northeastern Brazil. Among the key results was a strong habitat effect on dietary diversity (explaining ca. 40–50% of the variation), which, in edge colonies, decreased approximately by one fourth compared to interior colonies (inverse of Simpson's index: 3.7±0.84 versus 4.99±0.95). There was a predominance of leaf fragments collected from pioneer species in the diet in both habitat (86% in edge and 80.4% in interior). Edge colonies collected proportionally more fragments from pioneer species than colonies located in the forest interior. Our results are the first to demonstrate an edge-mediated relaxation of dietary restrictions in leaf-cutting ants. These findings render robust support to previous evidence indicating the reduction of bottom-up forces as a key factor explaining both edge-induced hyper-abundance and increased herbivory of leaf-cutting ants in human-modified Neotropical landscapes.

In many human-modified tropical landscapes, biodiversity conservation and the provision of ecosystem services require large-scale restoration initiatives. Such initiatives must be able to augment the amount and the quality of remaining natural habitats. There is thus a growing need for long-term, multi-stakeholder and multi-purpose initiatives that result in multiple ecological and socioeconomic benefits at the biome scale. The Atlantic Forest Restoration Pact (AFRP) is a coalition of 260+ stakeholders, including governmental agencies, private sector, NGOs and research institutions, aimed at restoring 15 million ha of degraded and deforested lands by 2050. By articulating, and then integrating common interests, this initiative has allowed different sectors of society to implement an ambitious vision and create a forum for public and private concerns regarding forest restoration. The AFRP adopts a set of governance tools so multiple actors can implement key processes to achieve long-term and visionary restoration goals. Having overcome some initial challenges, AFRP now has to incorporate underrepresented stakeholders and enhance its efforts to make forest restoration more economically viable, including cases where restoration could be less expensive and profitable. The AFRP experience has resulted in many lessons learned, which can be shared to foster similar initiatives across tropical regions.

Seed predation by small rodents is an emerging theme in the ecology of modified landscapes. Here we investigate the role played by the small rodent Oryzomys oniscus as a seed predator of large-seeded trees in a large remnant of the Atlantic forest - the Coimbra forest (3,500 ha), Alagoas state, northeastern Brazil. O. oniscus was captured and identified by setting twenty 500 m long transects, each one composed of 25 traps 20 m apart. This procedure resulted in 483 trap-nights set during a 20-mo period. We used 692 seeds (>15 mm length) from ten local large-seeded tree species for the seed predation trials that basically consisted of three treatments: one seed on the ground freely accessed by vertebrates (unprotected seed), one seed totally protected by an exclosure, and one partially-protected seed (exclosure just for medium-sized and large vertebrates). O. oniscus was captured throughout the Coimbra forest including forest edges (76 captures) and interior areas (67), and this small rodent was responsible for all seed predation visually documented inside exclosures. A 24 hours period of seed exposition permitted elevated rates of seed removal and predation. Seeds were much more removed/predated beneath fruiting trees, but rates varied according to the level of seed protection - 26.3% of predation among partially-protected versus 19.2% among unprotected seeds. Seeds suffered higher levels of seed predation/removal at the forest edge as well (up to 90%). In both habitats, most seeds (>84%) remained intact beneath trees without fruits, regardless of the level of seed protection. Our results suggest that O. oniscus may operate as an effective large-seed predator in forest fragments, in which adult trees without fruits constitute low resource spots and thereby provide, at least temporarily, safe sites for large seeds.