Grazing History Research Articles

Grazing legacy mediates the diverse responses of grassland multidimensional stability to resource enrichment

Long-term grazing and resource enrichment are known to affect grassland ecosystem stability independently. However, the interactive effects of grazing legacy and resource enrichment on ecosystem multidimensional stability (e.g., temporal stability (TS): the degree of constancy of ecosystem components over time and temporal resistance (TR): the ability of ecosystem components to withstand the environmental change) in grassland ecosystems remain underexplored. In this study, we conducted a field manipulation experiment to assess the impact of 4-yr of resource addition (water and nitrogen) on multidimensional stability of multiple ecosystem components and underlying drivers in Inner Mongolia steppe with 7-yr different experimental grazing history. We found that the positive effects of water + nitrogen addition on multifunctional TS increased with increasing grazing intensity and an opposing trend was observed for multifunctional TR response. However, neither grazing legacy nor resource addition had an effect on community compositional stability. Resource addition enhanced the stability of species evenness, CWM (community weighted mean) species biomass and CWM-traits. Furthermore, water + nitrogen additions stimulated soil temperature TS but reduced its TR in heavy grazing intensity, with high grazing intensity bolstering soil moisture stability. Multifunctional stability was primarily governed by species asynchrony, while stability of species evenness fostered compositional stability. In particular, TS of functional diversity enhanced multifunctional TS in light grazing intensity, while TS of CWM-traits promoted multifunctional TS in heavy grazing intensity. Our study underscores the decoupling responses of functional stability and compositional stability to grazing legacy combined with resource enrichment. These findings highlight that the significance of concurrently considering multiple stability dimensions and components for a comprehensive understanding of grassland ecosystem stability under intensifying land use and global change scenarios.

451 Establishing producer research sites for the development of beef and bison climate-smart agriculture

Abstract Greenhouse gas (GHG) emissions and livestock production are topics that are increasingly intertwined. While livestock production is frequently presented as harmful to the environment, this perception fails to consider the carbon sequestration that takes place in livestock grazing systems and the role that grazing ruminants have in maintaining healthy grassland ecosystems. Grazing lands, which are often unsuited to row crop agriculture, are estimated to account for 25% of the global soil sequestration potential for soil carbon storage. Grazing livestock producers are often overlooked in the GHG reduction conversation, despite over 70% of beef GHG emissions being attributed to the cow-calf sector, which is primarily grazing. Furthermore, there is a relative lack of data surrounding the implementation of climate-smart agriculture practices on grazing operations and a lack of cost-effective methods to measure carbon/GHG sinks and sources on these landscapes. The potential climate benefits are considerable, with nearly 940 million acres of rangelands in the U.S. supporting forage-based livestock production. South Dakota State University recently received funding to support a large-scale climate-smart project focused on grazing beef and bison. For this project, we are utilizing the Cottonwood Field Station that has over 80 yr of historical grazing data, along with six grazing beef and bison ranching operations in the Northern Great Plains. The work on these ranches will focus on measuring and monitoring the impacts of climate-smart NRCS land practices, including cover crops, improved pasture and range seedings, prescribed grazing, and prescribed burning. A significant focus will be extensive, annual soil sampling across these operations to continuously monitor changes in soil organic carbon, bulk density, texture, pH, and soil microbiome community profiles. Each operation will have GreenFeed methane pasture units deployed for 5 yr to monitor changes in beef cattle and bison methane emissions in response to climate-smart practice adoption. We are also assessing biodiversity pre and post climate-smart practice adoption, as biodiversity improvements may be one of the most overlooked and yet most important responses to climate-smart land practice implementation. Over the duration of this project, a large-scale, comprehensive data collection will be achieved and used to refine GHG and carbon sequestration estimates associated with range livestock systems. Data resulting from this project will be used to inform research protocols and prediction models, fill knowledge gaps, and shape science-based discussions and marketing strategies for climate-smart agricultural commodities.

The impact of grazing on biodiversity and forest succession in the Brazilian dry forest region is constrained by non-equilibrium dynamics

The impacts of grazing on rangelands have historically been studied within the framework of the equilibrium model, which predicts significant impacts of grazing on ecosystems. However, in recent decades, studies have observed a non-equilibrium pattern, suggesting that abiotic factors play a primary role compared to grazing. These studies are primarily focused on rangelands, despite animal husbandry occurring in other biomes, such as seasonally dry tropical forests. Our study examines the influence of goat grazing on biodiversity and forest succession in the Brazilian dry forest (Caatinga). Considering its high interannual precipitation variability, we hypothesize a response that aligns with the non-equilibrium paradigm. We established a gradient of grazing intensity and history in areas at different stages of vegetation succession. A survey of tree - shrub and herbaceous species was conducted at each site and the biomass of both strata was quantified. Linear mixed models and Permanova were employed to assess differences in richness, composition, structure, and biomass among the areas. Our results suggest that grazing (history and intensity) and forest fallow age did not affect species richness, but only species composition. Low and high grazing intensity drive ecosystems toward similar compositions, which align with the non-equilibrium model predictions. Biomass in the herbaceous layer remained unaffected by grazing history, intensity, or forest fallow age, whereas woody biomass was influenced by grazing intensity in older forest fallows. Although trees in low-intensity grazing sites were significantly taller compared to those in other levels, overall, grazing did not disrupt the natural succession process. Older forest fallows exhibited greater diversity and higher basal area compared to new forest fallows, irrespective of grazing intensity. Our findings suggest that: a) grazing has minimal effects on biodiversity and biomass due to non-equilibrium dynamics, and b) with appropriate management, grazing can coexist with the conservation of the Caatinga.

The effect of livestock grazing on plant diversity and productivity of mountainous grasslands in South America - A meta-analysis.

Mountainous grasslands in South America, characterized by their high diversity, provide a wide range of contributions to people, including water regulation, soil erosion prevention, livestock feed provision, and preservation of cultural heritage. Prior research has highlighted the significant role of grazing in shaping the diversity and productivity of grassland ecosystems, especially in highly productive, eutrophic systems. In such environments, grazing has been demonstrated to restore grassland plant diversity by reducing primary productivity. However, it remains unclear whether these findings are applicable to South American mountainous grasslands, where plants are adapted to different environmental conditions. To address this uncertainty, we conducted a meta-analysis of experiments excluding livestock grazing to assess its impact on plant diversity and productivity across mountainous grasslands in South America. In alignment with studies in temperate grasslands, our findings indicated that herbivore exclusion resulted in increased aboveground biomass but reduced species richness and Shannon diversity. The effects of grazing exclusion became more pronounced with longer durations of exclusion; nevertheless, they remained resilient to various climatic conditions, including mean annual precipitation and mean annual temperature, as well as the evolutionary history of grazing. In contrast to results observed in temperate grasslands, the reduction in species richness due to herbivore exclusion was not associated with increased aboveground biomass. This suggests that the processes governing (sub)tropical grassland plant diversity may differ from those in temperate grasslands. Consequently, further research is necessary to better understand the specific factors influencing plant diversity and productivity in South American montane grasslands and to elucidate the ecological implications of herbivore exclusion in these unique ecosystems.

Effects of grazing in different intensities and 10‐year grazing exclusion on soil bacterial community composition and interaction complexity in alpine grasslands of the Qinghai‐Tibet Plateau

AbstractTo decrease the detrimental consequences of overgrazing on the sustainability of grassland ecosystems, many countries have developed policies on grazing exclusions. However, compared with grazing, how grazing exclusion modifies soil bacterial community and the associated environmental drivers is inadequately understood. Here, we studied the effects of grazing in different intensities (no grazing, light, moderate, and heavy grazing) and 10 years' grazing exclusion on soil bacteria community and associated environmental factors in the grassland of the Qinghai‐Tibet Plateau. The results showed significant changes in soil bacterial composition among all the treatments. After 10 years' grazing exclusion, the composition of the bacterial community rather than bacterial diversity was significantly different from that in grassland without grazing treatment. Under grazing exclusion, bacterial community composition was regulated by the total nitrogen and nitrate nitrogen. Grazing treatments decreased the complexity of the bacterial co‐occurrence network, but 10 years' grazing exclusion increased the complexity. This study found that grazing in different intensities substantially affected bacterial community structure and diversity, but 10 years' grazing exclusion hardly alleviated the historical grazing effects on the bacterial community structure. The findings of the study extended the understanding of how bacterial communities in grasslands respond to grazing in different intensities and grazing exclusion, providing a crucial scientific foundation for evaluating sustainable grazing management.

The interplay between historical land‐use and the distribution of Helichrysum shrubs in an African‐protected grassland

AbstractHuman land use can have lasting impacts on landscape characteristic, yet there remains a lack of information on how former land use affects plant communities in protected African grasslands. In this study, we investigated how land uses prior to the creation of Kitulo National Park, Tanzania, shaped the presence and abundance of the native shrub, Helichrysum species. We evaluated both plant species composition and soil properties across the park by dividing our sample into three different zones of historical land use based on participatory mapping. We divided the park into three former land uses: (1) livestock grazed and cultivated; (2) grazed only and (3) wild grazing with limited human impact. We observed that former grazed cultivated land use had five times higher Helichrysum abundance than former ‘wild’ land use. Soil pH, magnesium and phosphorus levels varied significantly across zones of historical land use but not between sites with and without Helichrysum species. Helichrysum splendidum was more abundant in soils with low soil phosphorus and magnesium concentrations. Our study demonstrates that historic grazing and cropping land uses through changes in soil nutrient properties can explain current Helichrysum species spread in protected areas. As such, conservation management plans would benefit from integrating mapping of former land uses to target interventions for problematic encroaching shrubs.

Grounded desires: Grazing regime, desires, and development in a Diné community

This article highlights the demands for development within the Diné community of Shonto in 2017. Using interviews with Shonto community members, I center the voices and desires of those most affected by development. Shonto is the site of conjuncture of a grazing regime that limits land use and a history of development that produces conflicting community desires for infrastructure, employment, and traditional livestock practices. Despite the plural views of development, community members express a collective desire for Diné continuity and self- determination. My research demonstrates that Diné desires for development are not monolithic but are grounded in land histories, a sense of shared collective continuity, and Diné self- determination. I draw upon Eve Tuck’s generative work on Native desire to demonstrate that land histories, in the form of a grazing regime and histories of development, inform Native desires for development. I argue that Native desires are grounded in historical and everyday land use and relations. These grounded desires center the lived-experiences of Natives in relation to development, colonial land regimes, and traditional practices. Moreover, these grounded desires draw from the daily lives and experiences of Native people to provide open narratives that do not impose expectations on Native peoples or their desires.

The effects of shrub encroachment on arthropod communities depend on grazing history

Unsustainable grazing is a major driver of biodiversity loss worldwide. Conservation actions such as grazing exclusion are effective strategies for halting such decline. However, we still know little how the long-term impact of grazing exclusion depends on plant–animal interactions such as those between encroaching unpalatable shrubs and ground arthropods. Here, we assessed how encroaching, unpalatable shrub species (Sarcopoterium spinosum) mediates the effects of grazing exclusion on the recovery of arthropod communities. We used a large-scale, long-term (15–25 years) grazing exclusion experiment complemented with local-scale treatments that consider the presence or absence of shrubs. We found that halting overgrazing supported the recovery of biodiversity in the long-term. Notably, the impacts of shrubs on arthropod diversity vary with grazing history. Shrubs decreased arthropod abundance by three folds, affecting particularly flies, butterflies, hymenopteran, and beetles in protected areas. Yet, shrubs had positive effects on animal diversity, particularly centipedes and millipeds in grazed areas. On the one hand, shrubs may enhance biodiversity recovery in overgrazed systems; on the other hand, shrubs may be detrimental in protected areas, in the absence of grazing. Understanding how plant–animal interactions vary with historical land-use change is key for biodiversity conservation and recovery and for integrated management of agroecosystems.

Applying two remotely-sensed methods for monitoring grazing impacts in the Australian arid zone

Objective monitoring methods that reliably identify grazing impact are required for long-term sustainable management in the arid rangelands. In Australia such methods must contend with highly unpredictable rainfall and large paddocks incorporating spatially complex land types with differing grazing preferences. Retrospective analysis of data collected following very dry and very wet periods removes vegetation dynamics generated by lesser rainfall events and should increase our ability to separate grazing effects from seasonal variability. Two remote-sensing methods were tested for their capacity to quantify trends over 30 years in vegetation-cover dynamics on a pastoral lease in central Australia with a history of heavy grazing. Following destocking by 2002, one section became a conservation reserve and another transitioned to a research station. During drought, the Dynamic Reference Cover Method (DRCM) showed that ground-cover deficit was less negative on both areas towards the end of the study. This improvement was attributable to increased ground cover after removal of grazing, followed by a reduced, but variable, grazing intensity on the research station and the spread of an introduced palatable perennial grass. Ground-cover response following rainfall was highest in 2011. Likewise, increased ground cover meant that the percentage Cover Production Loss (%CPL) index, calculated using grazing gradient methods (GGMs), was considerably less than a decade earlier following similar rainfall. Results from an associated recovery index (R) were inconclusive. Landscape heterogeneity potentially affected calculation of cover deficit using DRCM but, because heterogeneity was stable over time, reported change between dry years reliably indicated a trend owing to grazing. Interpreting trend from successive %CPL values in wet periods was complicated on the research station by altered waterpoint locations being superimposed on pre-existing degradation; however, the method should be effective in large paddocks with stable waterpoint locations. Despite their limitations, both methods can assist in objectively judging the long-term sustainability of grazing practices in contrasting seasonal conditions.

Medieval pastoralism: lessons for our landscape

The Faculty of Social and Historical Sciences at UCL highlighted heritage and conservation, the environment and biodiversity as key challenges to be addressed as part of its Strategic Vision for 2019–29. Staff at Archaeology South-East (ASE) are actively pursuing research into livestock and landscapes and how knowledge of past farming regimes has wider public benefit in terms of informing modern choices regarding food production, sustainability and nature recovery. The author of the present article has also engaged with conservation bodies on aspects of historic grazing and current rewilding projects. This article is intended as an introduction to the essential elements of this work, highlighting how archaeologists and heritage professionals can contribute to debates surrounding the future of our countryside. It draws on a previous blog post as well as themes pursued for associated publication outputs.

Interactions of long-term grazing and woody encroachment can shift soil biogeochemistry and microbiomes in savanna ecosystems

Semi-arid grasslands and savannas in the southern Great Plains USA are extensively used for livestock grazing. Over the past century, Juniperus (juniper) and Quercus (oak) species abundance have increased due to intensive grazing and reduced fire frequency. We investigated the interactions between livestock grazing history (none, moderate, heavy) and vegetation cover (grassland, juniper, oak) using a ∼ 70-year grazing experiment in west-central Texas. We explored effects on soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), microbial community composition, and function. SOC and TN were 50–150 % higher under juniper and oak compared to grasslands, and 10–30 % lower in grazed vs. ungrazed areas. Vegetation × grazing interaction showed greater SOC and TN loss under oak than juniper or grasslands. Ungrazed controls had higher soil TP than grazed areas, with oak and juniper soils having more TP than grasslands. Bacterial and fungal communities differed between grassland and woody vegetation. Grazing affected only bacterial communities. SOC, TN, TP accounted for differences in community structure. Abundances of genes related to methane, nitrogen, sulfur metabolisms, and dominant fungal trophic modes were linked to soil C, N, P ratios. These findings highlight how long-term livestock grazing and woody plant encroachment influence soil C, N, P cycles, altering soil microbial community structure and function. This study provides insights for savanna ecosystem management and integrating land cover effects into biogeochemical models for global change scenarios.

Moderate grazing weakens legacy effects of grazing history on primary productivity and biodiversity in a meadow grassland

Herbivore grazing has long-lasting effects on the structure and functions of grassland ecosystems, even after the grazing pressure has ceased. These lasting effects are known as grazing legacy effects and significantly affect plant productivity and biodiversity, with the magnitude increased with grazing intensity and further led to grassland degradation. Fencing is a common approach used for restoring degraded grasslands by excluding grazing. Moderate grazing representing a controlled level of grazing intensity is believed to be a useful way to restore ecological functions and thus mitigate grazing legacies. However, how fencing and ongoing moderate grazing affect grazing legacy effects remain unclear and rarely tested with field experiments, particularly with different grazing histories. Here, we investigated aboveground net primary productivity (ANPP), species richness, litter, soil organic carbon (SOC), soil dissolved nitrogen (DON) and hyphal length density (HLD) in 2015 (fencing for 1 year) and 2018 (fencing vs moderate grazing for the subsequent 3 years) after 0, 2, 5, 7 and 12 years of free grazing in a meadow steppe to explore how moderate grazing and fencing affect grazing legacy effects with different histories. We observed a decline in ANPP and species richness with increasing grazing histories, and the magnitude of grazing legacy effects increased accordingly. In most grazing histories, moderate grazing had a greater impact than fencing in reducing the grazing legacy effects on ANPP and species richness. However, with a grazing history of 12 years, moderate grazing led to a smaller increase in ANPP compared to fencing. Additionally, the grazing legacy effects on ANPP and species richness weakened with longer fencing duration for excluding grazing. Litter, SOC, DON and HLD exhibited consistent patterns with the dynamics of ANPP and species richness. Our results indicate that grazing legacy effects on ANPP and species richness intensify with prolonged grazing histories, suggesting that grazing history have stronger impacts on grassland ecosystem functions and structure. The study implies that moderate grazing is an effective strategy for restoring degraded grasslands, particularly for species richness and with short-term grazing histories, instead of relying solely on fencing. The changes of soil variables underlie the grazing legacy effects and the interactions with fencing and moderate grazing.

Carbon dioxide fluxes and soil carbon storage in relation to long‐term grazing and no grazing in Icelandic semi‐natural grasslands

AbstractQuestionWhat is the effect of long‐term grazing and no grazing (NG) on carbon dioxide flux and soil carbon storage in Icelandic semi‐natural grasslands.LocationThree farms, with known history of land use, in W Iceland.MethodsOn each farm, we located an intensively and an extensively grazed site, which both had been constantly grazed for centuries, and a parallel site with no grazing for over 50 years. We measured net ecosystem exchange (NEE), ecosystem respiration and normalized difference vegetation index on a regular basis over the growing season. Samples were taken from 60 cm deep soil profiles for analysis of soil organic carbon (SOC).ResultsThe grazed sites showed significantly more negative NEE than the NG sites, indicating more carbon dioxide uptake on the grazed sites compared to the NG sites. The normalized difference vegetation index was also significantly higher on the grazed sites. On all farms, the total SOC content was higher in the grazed sites than in the parallel NG sites.ConclusionsThe study indicates that cessation of grazing decreases productivity and carbon dioxide uptake in a semi‐natural grassland in Iceland, as well as SOC content in the soil. Historically, all the NG sites in the study had the same grazing history as the continuously grazed sites until grazing exclusion. The measured lower SOC on the NG sites seems to indicate that, without grazing, SOC is lost with time and/or grazing is needed to maintain SOC in these grasslands.

Understanding the drivers of ecosystem multifunctionality in the Mongolian steppe: The role of grazing history and resource input

Predicting the comprehensive driver of ecosystem multifunctionality is crucial for effective grassland management. However, the underlying biotic and abiotic mechanisms of ecosystem multifunctionality under global change and land use remain poorly understood. In this study, a 3-year field experiment was conducted in a semi-arid steppe in Inner Mongolia to investigate the relative importance of different biotic and abiotic factors in regulating aboveground ecosystem multifunctionality (AEM) and belowground ecosystem multifunctionality (BEM) in response to resource input after long-term grazing. The experiment involved three grazing intensities (1.5 low, 4.5 moderate, and 9.0 high sheep/ha) with a 7-year difference in grazing history. Precipitation (W) and nitrogen deposition (N) were manipulatively increased during the growing season. The study focused on exploring the effects of various biotic factors (e.g. species richness, functional diversity, plant functional groups) and abiotic factors (e.g. soil environment variables) on AEM and BEM. The results revealed asymmetric responses of AEM and BEM to resource input. Resource input enhanced AEM, but not BEM. However, increasing grazing intensity substantially reduced BEM, though we noted that AEM and BEM decreased the most under moderate grazing. Interestingly, the study found consistent responses of single ecosystem functions and ecosystem multifunctionality to resource input across the three grazing blocks. Structural equation modeling (SEM) analysis indicated that species richness primarily enhanced AEM, while soil environment played a major role in promoting BEM across different grazing history intensities and the whole grazed system. Multiple biotic and abiotic factors with varying relative importance in different grazing history scenarios controlled AEM and BEM. Species richness exhibited a strong influence on AEM and BEM, but within a narrow effect threshold range, whereas soil environment had a lesser effect size but a wider threshold range. This study provides the first evidence that grazing history and resource enrichment jointly regulate AEM and BEM. The findings highlight the importance of considering biodiversity conservation, soil health, and land use history in management practices aimed at maintaining ecosystem multifunctionality under climate change and human activities scenarios.

Pollen analysis of middle to late Holocene records shows little evidence for grazing disturbance to alpine grassland on the Tibetan Plateau until modern times

Understanding human impact on the vegetation of the Tibetan Plateau through the Holocene is important for developing strategies for sustainable ecosystem management in the region. In this paper, 53 pairs of surface-soil samples from inside and outside livestock enclosures were obtained from across the Tibetan Plateau to investigate the differences in pollen assemblages between grazed and ungrazed sites. This modern dataset was then applied to palynological records from four lakes in the northeast Tibetan Plateau region to investigate middle to late Holocene grazing history. Results show that modern grazing activities have a limited impact on the vegetation, although grazing activity leads to an increase in the pollen proportion of Cyperaceae, Artemisia, Ranunculaceae, Brassicaceae, Taraxacum-type, Fabaceae, and Saxifrageceae while representatives of Poaceae, Chenopodiaceae, and Aster-type pollen decrease. Application of these grazing indicators to the pollen spectra obtained from the four lake sites, together with other proxies, reveals that grazing activity only commenced during the last few hundred years in the northeast marginal areas of the Tibetan Plateau at c. 3000 m a.s.l, while there is no grazing signal in pollen records from above 4000 m a.s.l. Our study emphasises the importance of using multi-proxy methods in estimating signals of past human activity.

Influence of Livestock Grazing History on Plant Community Composition on Native Prairies of the Southern Prairie Pothole Region

The southern Prairie Pothole Region (PPR) of central North America is a highly modified landscape where remnant unplowed prairies could serve as repositories of native plant biodiversity. A previous study paired two historically idle US Fish and Wildlife Service (USFWS) National Wildlife Refuges with nearby privately owned grazing lands in North Dakota and found differences in invasive grass frequency, notably that smooth brome (Bromus inermis Leyss.) was less prevalent on annually grazed lands. A broader assessment, conducted over a wider geographic area, was warranted to investigate whether this relationship held across the southern extent of PPR in North Dakota and South Dakota. To this end, we selected 26 USFWS native prairie sites paired with adjacent/nearby native prairie sites with a history of livestock grazing in the PPR of North Dakota and South Dakota. We estimated plant species’ cover in five 10 × 10 m plots at each paired site in June or July of 2021. Plant community composition on USFWS sites was distinct from paired sites under private or state ownership (permutational analysis of variance (P = 0.021, F = 1.935). Additionally, paired t-tests revealed that sites under private or state ownership (with a long-term history of grazing) had higher total species richness (P = 0.006) and floristic quality index (a measure of species richness and disturbance tolerance) values (P = 0.042) than USFWS sites (without a long-term history of grazing). Smooth brome relative cover was lower (P = 0.019) at sites with a long-term history of grazing (13.4% mean relative cover) than paired USFWS sites (23.3% mean relative cover). Given these differences, remnant native prairies with long-term histories of annual grazing may provide unique opportunities for conserving native plant diversity and impeding smooth brome spread in the southern PPR.

Grassland biodiversity response to livestock grazing, productivity, and climate varies across biome components and diversity measurements

Livestock overgrazing and climate change have been identified as the primary causes of grassland degeneration and biodiversity decline, yet the underlying mechanism remains unclear. To gain a better understanding of this, we conducted a meta-analysis of 91 local or regional field studies from 26 countries across all inhabited continents. Using concise statistical analyses, we assessed five theoretical hypotheses for grazing intensity, grazing history, grazing animal type, productivity, and climate, and decomposed the individual contributions of each factor in regulating multiple components of grassland biodiversity. After controlling for confounding effects, we found that: no significant linear or binomial pattern for the effect-size of grassland biodiversity as grazing intensity increased; the effect-size of producer richness was relatively lower (negative biodiversity response) in grasslands with a short grazing history, grazed by large livestock, high productivity, or high climate suitability; additionally, significant difference for the effect-size of consumer richness was only detected across grazing animal groups; and the effect-size of consumer abundance, and decomposer abundance all displayed significant differences with respect to grazing characters, grassland productivity, and climate suitability. Besides, results of hierarchical variance partitioning suggested that the total and individual contribution of predictors varied across biome components and diversity measurements. Specifically, grassland productivity acted as a key factor in driving producer richness. The findings presented here collectively suggest that the response of grassland biodiversity to livestock grazing, productivity, and climate varies across different components of the biome and measurements of diversity.

Impact of climate change on pasture quality in Mediterranean dehesas subjected to different grazing histories

Background and aimsForecasted climate change and overgrazing are threatening the sustainability of dehesas, human-managed ecosystems where pastures, livestock and scattered trees coexist. Pasture quality is particularly sensitive to these global-change drivers, but there are still many gaps to broaden knowledge about the interactive effects of both factors on it. In addition, scattered trees might play a relevant role in maintaining high levels of pasture quality under future scenarios of higher aridity, but its role remains largely unexplored.MethodsWe designed a field manipulative experiment of rainfall exclusion and increased temperature aimed to evaluate the impact of forecasted climate on pasture quality under different historical grazing intensities. To test the potential buffering effect of trees, experimental plots were installed equally in two habitat types: under trees and open grassland.ResultsWarming reduced the nutrient concentration of pasture, while drought increased it. Tree canopy improved soil fertility, which translated into an increase in pasture quality. Livestock exclusion and high grazing intensity caused a decrease in pasture quality, whereas moderate grazing intensity exerted positive effects on it. Finally, warming beneath tree canopy negatively affected the P concentration of pasture, specifically in the site subjected to moderate grazing intensity.ConclusionOur findings suggest that communities subjected to moderate grazing are more sensitive to climate change from a nutritional standpoint, likely because this management type provides high levels of P to the soil. In addition, we highlight the essential role of trees in agroforestry ecosystems to maintain high values of nutritional quality of pasture.

Spider Diversity in the Fragmented Forest-Steppe Landscape of Northeastern Ukraine: Temporal Changes under the Impact of Human Activity

Semi-natural forests and dry grasslands are highly fragmented and influenced by human activity. Despite the small area, they serve as the refuge for habitat-specific species and enhance agrolandscape biodiversity. We studied spiders in Velykoburlutskyi Steppe Regional Landscape Park (northeastern Ukraine) for 10 years and found 224 species of 26 families; of these, 27 are rare and require protection. The araneofauna of small forests in gullies is poorer than that of the large oakeries and hosts fewer sylvatic species; the dry grassland fauna is rich, has typical steppe traits, and varies depending on topography and grazing history. The ungrazed gully hosted 125 spider species. The richest assemblages (97 species) were at the bottom, and they were similar to those of meadows and forest edges. The most typical steppe assemblages were formed on the ungrazed slope (77 species). The human-induced disturbance had a negative effect on spiders: we found only 63 species at the grazed bottom and 62 on the slope. After abrupt grazing cessation, four spider species appeared and occurred constantly at the bottom, while no species left this habitat. Grazing on the slopes declined gradually, and spider assemblages did not change significantly after the final cessation; moreover, they enriched on the abandoned slope (75 species). The presence of rare species and a variety of spider assemblages confirm the conservation value of the study site and the need to maintain its mosaic pattern.

Review on Ruminant Fasciolosis in Ethiopia

Ethiopia possesses the largest livestock population in Africa. Ruminant Fasciolosis is a serious problem in animal production in different areas of the world especially in Ethiopia. It is a wide spread trematodal disease affecting ruminants (cattle, sheep and goats) and also other species of animals. F. hepatica and F. gigantica are the parasitic species belonging to Genus Fasciola under the phylum platyhelminths. The fasciola disease has three phases of clinical sign acute, sub-acute and chronic forms. Fasciolosis is more apparent in young ruminant and is usually chronic in nature. Adult flukes in the bile ducts cause inflammation, biliary obstruction, distraction of liver tissue and anemia. Snails of family Lymnaeidae are main intermediate hosts having great role on the transmission of the disease and the infection is acquired through grazing on swampy pasture. The disease mostly diagnosed by prior knowledge of the epidemiology of the disease in a given environment; observation of clinical signs, information on grazing history, seasonal occurrence and standard examination of feces in the laboratory. The affected cattle should be effectively treated with narrow spectrum anthelmintic such as Triclabendazole in addition to reducing the population of the intermediate host to control the disease. Now a days, fasciolosis is recognized as emerging human disease over the world even if only few case reports of human fascioliasis are available in Ethiopia, as the disease mostly affects animals in the country. The disease causes a significant economic loss in ruminant production by inflecting direct and indirect loss at different parts of Ethiopia. To control and prevent the disease, the strategic destruction of snail population should be implemented throughout the country to break down the life cycle of liver fluke.