关键词： Browsing   Seedling and sapling bank   Herbivory   Natural regeneration   Sorbus aucuparia   Coarse woody debris   Red deer   Subalpine spruce forest   Hiking trails   Ungulates  

摘要： Browsing damage by ungulates is among the most decisive factors affecting the establishment and growth of young trees. In recent decades, ungulate populations have been expanding in the Northern Hemisphere;impairment of tree regeneration by their activity is an increasing problem. Herbivore-induced changes in tree regeneration may alter the composition and biodiversity of the future tree stand. In this study we determined where young trees can leave the seedling bank and succeed to higher forest strata in a protected natural forest that is under strong herbivore pressure. We studied rowan (Sorbus aucuparia) regeneration in a subalpine spruce forest growing in a strictly protected area of Babia Gora National Park (Western Carpathians). Rowan is one of the most palatable forest species, so browsing can significantly limit its growth. We predicted that factors, that restrict the movement of red deer (Cervus elaphus), decrease their visits in some forest patches, which will result in a higher share of rowan saplings. We also considered two other factors that can affect the distribution of rowan saplings: light availability and distance to maternal trees. In particular, we tested whether the occurrence of rowan saplings was related to: (i) slope angle, amount of logs lying on the forest floor, and distance to the hiking trails;(ii) distance to fruit-bearing trees;and (iii) canopy openness. The results confirmed our main predictions concerning the relation between the occurrence of palatable tree saplings and the availability of a forest area to ungulates. Factors related to the availability of terrain to red deer significantly influenced the distribution of rowan saplings taller than 1 m. The probability of rowan sapling occurrence increased when the amount of logs was higher and the distance to hiking trails was shorter. Slope had a significant negative impact on sapling occurrence. We found no effect of proximity of fruit-bearing rowan trees or canopy gap area. Thus, i

关键词： Liveweight   Orinoco basin   Reproductive performance   Soil emissions   Tropical grass  

摘要： Beef cattle production constitutes the main land use in the neotropical savannas of the eastern Colombian Orinoquia. However, the effects of Brachiaria decumbens Stapf (Bd) pastures and the alternative combination of savanna and B. decumbens pastures (SaBd) to raise and breed tropical beef heifers and cows, and their impacts on methane (CH4) emissions and overall carbon (C) footprint are still unknown. This study aimed to predict CH4 emissions, animal-environmental metrics and overall C footprint across heifers' growth, cow-calf-bull and cull cows' fattening productive stages of Brahman (Bos indicus) breeding herds, lifetime-grazing on B. decumbens pastures or a sequence of native savanna and B. decumbens pastures. A dynamic model-method was used with detailed liveweight (LW) and productive lifetime-cows' data together with estimated values of above- and belowground pasture biomass and soil C stocks. This framework recognized commercial farming practices such as growing and mating female herds on Bd (Bd scenario) or rising them on savanna and grazing Bd pastures (SaBd scenario) during the herd's breeding life. The study complemented this socio-economic, cultural and productive tradition by fattening cull cows using the improved Bd pasture and illustrated the cointegrating relationship with structural-flows of LW-derived CH4 emissions. As heifers aged, accumulated CH4 emission efficiencies [t carbon dioxide (CO2) equivalent (CO2-eq) head(-1)] were lower in the Bd scenario than in the SaBd scenario from birth to conception (2.67 +/- 0.087 vs 3.49 +/- 0.087;P < .0001), while following the same trend, emissions from the first to the fourth lactation were in the range of 0.821-0.865 (P < .05) between scenarios, but similar in the two other lactations. Methane efficiency estimates from cow-calf pairs (t CO2-eq kg(-1) calf born) tended to be lower in the Bd scenario than in the SaBd scenario up to the fourth lactation. In the extreme, calculated values during the fattening

关键词： activity   artificial tree hollow   BACI   biodiversity offset   habitat restoration   nest box   supplementary shelter sites  

摘要： Anthropogenic disturbance has resulted in a global reduction in the abundance of mature, hollow-bearing trees. Nest boxes have long been used to provide supplementary shelter sites in revegetated and regenerating landscapes, but limitations in their effectiveness when offsetting the loss of mature trees has led to increased interest in novel designs of artificial hollows. For example, mechanically excavating cavities into the trunk or branches of trees. However, the effectiveness of artificial hollows in attracting wildlife to visit small- or medium-sized, growing trees in human-disturbed landscapes has received little attention. In this study, we installed chainsaw hollows that were designed for small, hollow-dependent mammals and birds into the trunks of live medium-sized trees. We conducted a before-after control-impact experiment using passive camera traps to monitor changes in visitations by wildlife to (1) mature hollow-bearing trees, (2) developing trees without hollows (i.e. control trees), and (3) developing trees with newly installed chainsaw hollows. We found that, compared to large hollow-bearing trees and control trees, the developing trees that were selected for chainsaw hollow construction showed the greatest visitation rates by hollow-dependent wildlife (i.e. number of visits) during the "post-impact" surveys. Our results suggest that chainsaw hollows designed to replicate the external physical characteristics of natural tree hollows could be effective in attracting target hollow-dependent fauna to developing trees in regenerating and revegetated landscapes. Further studies are required to compare the effectiveness of natural hollows, chainsaw hollows, and nest boxes when deployed in a range of human-disturbed landscapes.

关键词： 树鼩   人工驯养   粪便   菌群组成  

摘要： 从云南昆明西郊野外捕捉6只成年野生树鼩,于中国科学院昆明灵长类研究中心人工驯养6个月。于刚捕捉回(野生组)和人工驯养6个月(驯养组)时,收集新鲜粪便样本,共12份,运用IlluminaMiSeq测序平台,以16S rRNA的V3–V4区域为目标进行高通量测序,比较分析树鼩在人工驯养前后粪便菌群的多样性及组成。结果表明:树鼩粪便菌群的OTU多样性Shannon指数和Simpson指数组间的差异均无统计学意义,野生组树鼩粪便菌群的OTU丰富度Chao指数、Ace指数、Sobs指数均显著高于驯养组的;PCo A主成分分析结果显示,野生树鼩与人工驯养树鼩的粪便菌群具有明显的差异,但同组内个体间的菌群差异不明显;在门水平上,树鼩粪便的优势菌门主要有厚壁菌门、拟杆菌门、变形菌门,但其在不同组树鼩粪便菌群的相对丰度不同;在纲水平上,野生组菌群主要有芽孢杆菌纲和拟杆菌纲,驯养组菌群主要有拟杆菌纲、梭菌纲和厌氧菌纲,γ–变形菌纲、厌氧菌纲相对丰度在2组间的差异有统计学意义(P<0.05);在目水平上,野生组菌目主要有乳杆菌目和拟杆菌目,驯养组菌目主要有拟杆菌目和梭菌目,驯养组的Selenomonadales相对丰度显著高于野生组的(P<0.05);在科水平上,野生组菌科主要有链球菌科和普雷沃氏菌科,驯养组菌科主要有普雷沃氏菌科和韦荣氏球菌科,驯养组的韦荣氏球菌科相对丰度显著高于野生组的(P<0.05);在属水平上,野生组菌属主要有链球菌属和乳球菌属,驯养组菌属主要有普雷沃菌属和巨单胞菌属,野生组的链球菌属相对丰度极显著高于驯养组的(P<0.01),驯养组的巨单胞菌属相对丰度显著高于野生组的(P<0.05)。可见,野生树鼩经过人工驯养后,粪便微生物区系中的一些菌群发生了变化,菌群结构与野生组有差异,但不显著,粪便菌群结构变化呈简单化的趋势。

关键词： feral cattle   fire   landscape ecology   macropods   wildlife surveys  

摘要： Australian mammals have exhibited exceptionally high rates of decline since European settlement 230 years ago with much focus on small mammals in northern tropical savannas. In these systems, little scientific attention has been given to the suite of grazing macropods, family Macropodidae, (common wallaroo (Osphranter robustus), antilopine wallaroo (O. antilopinus) and agile wallaby (Notamacropus agilis)). These species may be impacted by feral herbivores and contemporary fire regimes, two threats linked to small mammal declines. A multi-scale approach using aerial surveys, road surveys and camera trapping was utilised to determine the effects of feral cattle and fire on the distribution and abundance of large macropods in the North Kimberley bioregion. Feral cattle density and biomass exceeded that of macropods regardless of survey technique. Density estimates for cattle were up to 125 times higher (0.3-10.0 km(-2)) than estimates for macropods (0.08-0.49 km(-2)). Cattle biomass, based on the aerial survey estimates (corrected for perception bias), were 15 and 95 times higher than macropods for infertile (279 vs. 19 kg km(-2)) and fertile savannas (518 vs. 5 kg km(-2)), respectively. Proximity to the nearest pastoral station was a significant predictor of the aerial sightings of feral cattle (P <= 0.05). Abundance and foraging activity of cattle were positively associated (P <= 0.05) with recently burnt areas. In contrast, camera trapping showed agile wallaby and wallaroo occurrence and foraging were associated with longer unburnt areas (P <= 0.05). Agile wallaby and wallaroo were negatively associated with cattle (P <= 0.05) and showed substantial diurnal and seasonal separation consistent with an antagonistic interspecific interaction. Results also suggest that the agile wallaby is the primary prey of the dingo, not wallaroo. Collectively, this study suggests that recent landscape changes such as altered fire regimes and introduced herbivores have negatively impa

关键词： Trophic cascades   Camera trapping   Enclosed reserve   Mesocarnivore release   Spatial dynamics  

摘要： Trophic cascade theories such as the 'behaviourally-mediated trophic cascade hypothesis' (BMTCH), have mainstreamed as ecological tools for conserving biodiversity and restoring ecosystems. The BMTCH relies on indirect negative effects of large carnivores through suppression of mesocarnivore activity and habitat use. Importantly, effects of top carnivores on mesocarnivores varies over time and space, is dependent on the species involved, and local context. In South Africa, there are very few free-ranging carnivores, as populations are often restricted to enclosed reserves. While predator-proof fences reduce human-wildlife conflict, they also influence space use within communities. We used an enclosed reserve with a relatively full complement of carnivores to test the generality of the BMTCH in the African context. Using single-species, mull-season occupancy models we investigated the spatial dynamics of multiple carnivores. We also investigated spatial partitioning by vegetation type and temporal partitioning. Our results revealed both support for and against the BMTCH. Lions and spotted hyaenas negatively influenced the detection probability of black-backed jackals and African wildcats, while leopards had a positive effect on these two mesocarnivore species. Additionally, lions positively influenced the detection probability of side-striped jackals. Although space use of carnivores in relation to vegetation type showed minimal evidence of spatial partitioning, each carnivore had a unique combination of abiotic and biotic factors influencing their spatial dynamics, which could facilitate co-existence. Temporal partitioning may also be promoting co-existence as activity patterns of smaller carnivores overlapped the least with sympatric carnivores, particularly lions. Extensive activity overlap between large carnivores does not promote co-existence. We suggest that applying the BMTCH as a universal law across ecosystems is unsupported and may lead to inappropriate con

关键词： Bone shaft   Egg shell   Snail shell   Supplementation   Edible fungi   Mineral enrichment  

摘要： Calcium assimilated by edible fungi cultivated on two palm tree wastes viz.;coconut husk with coir (CH), and palm kernel fibre (PK) supplemented with egg shell of chicken (ES), snail shell (SS), bone shaft of cow (BS) at different ratios or with 1.5% w/w calcium compounds as a calcium-rich substrate was *** ostreatuscultivated on (CH + ES + SS) and (CH + 1.5% w/w CaCO3) have the highest (P < 0.05) biological efficiency of 57.70% and 56.91%, *** squarrosulusfrom (PK + ES) and (CH + 1.5% w/w CaCO3) also has relatively high (P < 0.05) biological efficiency of 54.09 and 53.41%.Lentinus squarrosulusharvested from (CH + ES + SS + BS) have the highest protein content of 6.50%, followed byP. ostreatusharvested from (PK + ES + SS + BS) with 6.40%.Pleurotus ostreatusandL. squarrosulusharvested from non-calcium supplemented substrates respectively have the lowest calcium content of 125.0-133.0 mg/100 g and 105.0-185.0 mg/100 g.P. ostreatusharvested from (CH + ES + SS) have the highest calcium content of 596.6 mg/100 g with Absorption Ratio (AR) of 4.6, whileL. squarrosuluscultivated on (PK + ES + SS + BS) have calcium content of 510.6 mg/100 g with the highest AR of 4.8. Fortification of lignocellulosic wastes with calcium salts or animal wastes that are rich in calcium is a good substrate mixture to produce calcium-enriched mushrooms, which will pacify calcium deficiency aliments. [GRAPHICS] .

关键词： Tree forages   Animal feed   Arid zone   Algarobo  

摘要： Mesquite tree (Prosopisspp.), is an important species in arid zones, due to its nitrogen-fixing and adaptability to drought seasons, it also provides food for many species of wild animals which feed on its nectar, pollen, leaves and pods. This plant is an excellent source of protein, fiber, sugars and phytochemical compounds such as alkaloids, tannins, phenolics, steroids, terpenes and flavonoids. Mesquite has been used in farm animal nutrition as supplement with recommended proportions between 20 and 40%. The nutritional contributions also depend on the usage of pods or foliage, however, most of the studies highly recommend an enzymatic pretreatment to increase the biomass digestibility. Its nutritional characteristics and ability to grow under scarce water conditions turn it as a potential source to replace expensive forages for farm animal feeding especially in semiarid regions;however, the results in animal feeding are diverse. The usage of tree species in arid zones for animal feeding has been long proposed, but, forProsopisspp. there are few updated studies despite of its potential usage. This work presents a general overview of the mesquite tree usage in animal feed.

关键词： Arthropod diversity   Community structure   Functional diversity   Invasive alien plants   Invasion ecology   Species richness  

摘要： Plant invasions can modify the composition of native communities through altering diversity and ecosystem functioning. For example, arthropod communities can be influenced by the introduction of invasive plant species, but the impacts of plant invasions on arthropod communities have received little attention. Here, we investigated the diversity and species composition of arthropods in areas with and without invasive plants by comparing native ecosystems and areas invaded by Acacia dealbata, A. longifolia and A. melanoxylon in 18 locations in the northwestern Iberian Peninsula. Yellow sticky traps were placed in branches above ground in randomly selected areas and used to qualify and quantify the number of aerial arthropods. The aim was to assess the impact of invasive Acacia on arthropod species in different ecosystems. Our results demonstrate that arthropods are negatively influenced by Acacia invasions, reducing the abundance and diversity in invaded areas, which had substantial effects on beta-diversity and trophic levels. Overall, our findings indicate that invasive acacias can alter the species composition by not only reducing abundance and diversity but also altering the different trophic groups of the arthropod assemblages. The physical dominance of Acacia invaders alters the co-occurrence of arthropod assemblages, reducing the number of groups and leading to substantial effects on ecosystem dynamics as well as in the trophic diversity. We suggest implementing management strategies to favour the protection of native ecosystems and reduce the impacts of these exotic plants on arthropod biodiversity at the habitat level.

关键词： Habitat type   parasitope   rodents   South Africa   Trombiculidae  

摘要： Chigger mites (Trombiculidae) are temporary habitat-specific ectoparasites that often occur on rodents. Little ecological data are available on chiggers associated with rodents in South Africa. The study aims were to (1) record the chigger species associated with rodents in the savanna, (2) assess if chigger species display parasitope preference on the rodent body and (3) compare the distribution of chigger species in natural, agricultural and urban habitats. Rodents (n= 314) belonging to eight genera were trapped in the savanna biome during 2014 and 2015. Twelve chigger species, of which five are recently described species, were recorded from 161 rodent hosts. The data include three new country locality *** mastomyiawas the most prevalent species across sampling seasons and habitat types. Significant parasitope preference was recorded for two species, with the ear, face and tail base some of the preferred attachment sites. Sampling season and habitat type had a significant effect on chigger communities with summer and agricultural habitats recording the highest species richness, while the highest species diversity was recorded in natural habitats. The study contributes to our current knowledge regarding rodent-associated chigger diversity and distribution in South Africa and further highlights the importance of environmental characteristics in shaping chigger communities.