Detecting trends in the quality and productivity of grasslands by analyzing the historical vegetation relevés: A case study from Southeastern Carpathians, Vlădeasa Mountains (Romania)

Grassland ecosystems are essential for biomass production but are prone to degradation if management practices are inappropriate. Thus, it is necessary to optimize grazing management since the grazing practices and grassland status are interconnected. Herbage mass production and forage quality of the plant species are among the most important factors for grazing livestock performance, grassland carrying capacity, and their sustainable management. We employed optimized methods for the analysis of two historical vegetation datasets (from 1970 and 2008), along with the statistical data on livestock numbers and types from three administrative units within the Vlădeasa Mountains area, in the Romanian Carpathians. We looked for trends in grassland quality and productivity and explored their connections to grazing management descriptors and practices. We identified a small but statistically significant decreasing trend between the two periods in both pastoral value (from 63.80 to 61.43) and productivity (from 10.80 t ha-1 to 9.18 t ha-1). The decline in grassland quality and productivity may be associated with the sharp decrease in livestock numbers (from 9,688 LU to 5,085 LU) and the replacement of cattle by sheep as the dominant livestock type. The abandonment of grasslands and traditional practices also increased the deviation from the optimum of the actual stocking rate. This approach can be used as a model for other areas where time-series vegetation data are available from phytosociological literature and/or databases. These insights can be used to design adaptive grazing management plans to optimize grazing management according to the carrying capacity of the grassland ecosystems.

Plant Diversity in Sardinian Mountain Rangelands: Analysis of Its Relationships with Grazing, Land Management, and Pastoral Value

In this study, we analyzed the effects of grazing on native and endemic plant diversity, as well as its relationship with pastoral value along a gradient of abiotic and biotic factors and types of land management in a mountainous area of central-eastern Sardinia, Italy. Plant diversity was estimated by conducting a floristic survey within plots. In total, 231 plant species were recorded in 63 plots distributed within the study area, and this total number included 20 endemic species. Species richness was mainly affected by the type of management, soil attributes, altitude, and bioclimate. Pastoral value was strongly affected by nutrient availability and bioclimate. Our results suggest that the cover of endemic species increases with altitude. Finally, in Sardinian rangelands, a negative effect of grazing pressure on endemic species was observed.

Spatial Distribution of Highland Cattle in Alnus viridis Encroached Subalpine Pastures

Green alder (Alnus viridis) is a shrub species that has expanded over former pastures in Central Europe due to land abandonment, leading to negative agri-environmental impacts, such as a reduction in forage yield and quality and an increase in nitrate leaching. Robust livestock breeds such as Highland cattle could be used to control A. viridis encroachment. The objectives of this study were to investigate the impact of A. viridis encroachment on plant community composition and diversity and to map the spatial distribution of Highland cattle in A. viridis-encroached pastures. During the summer of 2019, three different Highland cattle herds were placed along an A. viridis encroachment gradient. A total of 58 botanical surveys were carried out before grazing to assess plant community composition, pastoral value, and ecological indicator values. The spatial distribution of cattle was studied during the whole grazing period by monitoring six to eight cows equipped with GPS collars in each herd. Plant species associated with higher pastoral values of the vegetation were found in areas with lower A. viridis cover, while highly encroached areas were dominated by a few nitrophilus and shade-tolerant broad-leaved species and by ferns. Cattle spent more time in areas with higher pastoral value but did not avoid areas with high cover of A. viridis, on steep slopes or far from water. These results show that Highland cattle are able to tolerate harsh environmental conditions and that they can exploit A. viridis-encroached pastures. This suggests that they have a high potential to reduce A. viridis encroachment in the long-term.

Caractérisation des pâturages herbacés sahéliens à accès limité : Cas du Centre Secondaire de Multiplication de Bétail de Sayam (Diffa).

Objectifs : Cette étude vise à caractériser l’état actuel des pâturages herbacés du Centre Secondaire de Multiplication de Bétail de Sayam. Méthodologie et Résultats : Quatre groupements pastoraux ont été identifiés et décrits à partir de 56 relevés linéaires réalisés sur un transect Sud - Nord. Au total 98 espèces herbacées réparties parmi 59 genres et 27 familles botaniques ont été répertoriées. Les genres suivants : Eragrostis, Ipomoea, Aristida, Cenchrus, Indigofera, Digitaria et Brachiaria ont été les mieux représentés. Ils représentent environ 50% du total et renferment l’essentiel des espèces de bonne valeur pastorale. Le recouvrement global, les valeurs pastorales brutes et nettes sont respectivement de 85,5%, 75,05% et 67,56%, celles-ci attestent que le pâturage du centre est de bonne qualité. La productivité globale en phytomasse herbacée a été estimée 2,26 tMS/ha avec une capacité de charge globale de 0,40 UBT/ha/an soit 2,5 ha/UBT/an. L’analyse du spectre fourrager indique que les espèces de bonne valeur pastorale et de faible valeur pastorale dominent le tapis herbacé. La première catégorie domine la zone centrale mieux protégée tandis que la dernière occupe les parties périphériques soumises à une forte exploitation du bétail. Conclusion et application des résultats : Le front de colonisation des espèces faiblement appétées (espèces qui ont IS = 0 ou IS = 1) progresse vers le centre sous l’effet de la forte pression pastorale. D’où l’urgence de clôturer l’ensemble du périmètre du centre afin d’éviter de créer un déséquilibre écologique préjudiciable à la survie de nombreuses espèces inféodées à ces milieux particuliers. Dans les perspectives d’une gestion durable des ressources fourragères des centres secondaire de multiplication de bétail, ce travail fournit des informations scientifiques fiables sur l’état actuel des pâturages herbacés de ce centre. Mots-clés : Kouri, composition floristique, groupements pastoraux, qualité pastorale, Sayam. Idrissa et al., J. Appl. Biosci. 2020 Caractérisation des pâturages herbacés sahéliens à accès limité : Cas du Centre Secondaire de Multiplication de Bétail de Sayam (Diffa). 16096 Characterization of Sahelian herbaceous pastures with limited access: Case of the Secondary Cattle Multiplication Center of Sayam (Diffa). ABSTRACT Objectives : This study aims to characterize the current state of the herbaceous pastures of the Sayam Secondary Cattle Multiplication Center. Methodology and Results : Four pastoral groups have been identified and described from 56 linear surveys carried out on a South - North transect. A total of 98 herbaceous species distributed among 59 genera and 27 botanical families have been listed. The best represented genera are: Eragrostis, Ipomoea, Aristida, Cenchrus, Indigofera, Digitaria and Brachiaria. They represent about 50% of the total and contain most of the species of good pastoral value. The overall recovery, the gross and net pastoral values are respectively 85.5%, 75.05% and 67.56%, these attest that the pasture of the center is of good quality. The overall productivity of herbaceous phytomass was estimated at 2.26 tMS / ha with an overall carrying capacity of 0.40 TLU / ha / year, ie 2.5 ha / TLU / year. Analysis of the forage spectrum indicates that species of good pastoral value and those of low pastoral value dominate the grass cover. The first category dominates the better protected central zone while the last occupies the peripheral parts subject to heavy livestock exploitation. Conclusion and applicability of results : The colonization front of poorly palatable species is progressing towards the center under the effect of strong pastoral pressure. Hence the urgency to enclose the entire perimeter of the center in order to avoid creating an ecological imbalance detrimental to the survival of many species dependent on these particular miles. With a view to the rehabilitation and sustainable management of these pastoral centers, this study provides additional information on the current state of the herbaceous pastures in this center. Keywords : Kouri, floristic composition, pastoral groups, pastoral quality, Sayam, Niger

On the Physicochemical Characteristics and Applications of an “Undesirable” Pyrenean Thorny Cushion Dwarf: Echinospartum horridum (Vahl) Roth

Small evergreen shrubs of the family Fabaceae represent a large proportion of current Mediterranean mountain vegetation. Their low pastoral value and tendency for encroachment makes these plants undesirable. In this paper, the thermal and chemical characteristics of Echinospartum horridum, a thorny cushion-shaped dwarf shrub native to the French Central Massif and the Pyrenees (particularly dominant in the shrublands of the Pyrenees), have been analyzed with a view to its valorization. Although the higher and lower heating values of the biomass from E. horridum met the ISO 17225-2:2014 requirements for its use in pellets, the ash content was slightly above the upper limit, so it would not comply with the normative for its acceptable use as a fuel. Nevertheless, the presence of high added-value flavonoids and lignans in its extracts, which are receiving increasing recent interest as efficient anti-tumor drugs and antivirals, may open the door to the valorization of this shrub for pharmacological applications.

Floristic diversity and management of fodder resources of the natural pastures of the Savanna Highlands of Western Cameroon

Sustainable management of pastoral resources requires knowledge in terms of floristic diversity and productivity of the rangelands. The objective of the present study carried out in the Bamboutos Mountains was to assess the floristic diversity and carrying capacity of the natural pastures. Floristic inventory was done using the method of quadrat point aligned in 15 plots of 400 m². Aerial phytomass of herbaceous plants was measured by the full harvest method. A total of 74 species, including 09 woody plants belonging to 56 genera and 20 families were recorded. The number of taxa recorded in the plots varied from 11 to 36 species. Imperata cylindrica with a specific contribution of presence of 17.45% was the most abundant species in the rangeland. The species-richest families were Poaceae, Fabaceae, Asteraceae and Cyperaceae. The calculated pastoral value of the pasture was 56.21%. These pastures were dominated by phanerophytes (29.72%) and therophytes (24.32%). The forage productivity of the grazed area, estimated based on the regrowth biomass was 6498.57 kg DM/ha while the carrying capacity of the rangeland was 2.31 TLU/ha. These results showed that the fodder potential of the Bamboutos Mountains is enough diversified but remains under exploited.

Environmental and management drivers of alpine grassland vegetation types

Current vegetation of alpine grasslands has been shaped by the combination of natural ecological factors (such as climate, soil, topography) and human activities, mainly represented by animal grazing and agricultural practices. An assessment of these factors can explain the present composition of plant communities and help to evaluate the future development of rangeland vegetation. Nowadays, the analysis of the botanical composition of grasslands is of a major importance in order to propose appropriate management plans for the sustainable exploitation of pastoral resources and their future conservation. The main purpose of this work was to assess the relevance of ecological and management factors in alpine grasslands in an area located in eastern Italy, currently used for extensive grazing, and to describe the main factors that affect the characteristics of pasture types. To this aim, about 900 ha of alpine grasslands were surveyed in Val Visdende (northern Veneto, province of Belluno, Italy) by means of 189 linear transects. Some environmental variables (altitude, slope, aspect) and factors related to management (pastoral value, animal excreta, distance from night barns) were collected for each botanical transect. Landolt indicators were calculated in order to evaluate the ecological space occupied by each type. This assessment made it possible to identify the most relevant grassland communities (namely nutrient poor, shrub encroached, nutrient rich and humid pastures) occurring in the studied area, the effectiveness of ecological indicators to describe and to differentiate vegetation groups and the effect of animal management and ecological factors in the discrimination of grassland types.

Floristic Diversity and Pastoral Value of Permanent Grassland Fertilized in Conventional and Organic System

Permanent grassland is the most complex natural ecosystem due to the biodiversity of the structural and functional elements that characterize the space and time unit of this ecosystem. From this point of view, in the case of this ecosystem, biodiversity is manifested by the richness of species as a result of the interactions between species and the biotope, the interspecific relations and the effects of the technology and usage applied to the improvement of these surfaces. The paper presents the results obtained in an experimental device placed on a permanent grassland of Festuca valesiaca + Festuca rupicola, from Caraş-Severin County, under conditions of mineral and organic fertilizers application (sheep manure and direct fertilization by sheep folding).