Fodder Shrubs Research Articles

Variation of the chemical composition of four forage shrubs (<i>Albizia lebbeck, Leucaena leucocephala, Morinda lucida</i> and<i> Senna siamea</i>) in dry season in southeast of Gabon

Objective : This study is conducted, to know the chemical composition at different periods of the dry season, of four major fodder shrubs ( Albizia lebbeck, Leucaena leucocephala, Morinda lucida and Senna siamea ), used to supplement poor fodders in animal feed, in the conditions of southeast Gabon. Methodology and results: The leaves of each species were harvested at the beginning, at mid-season and at the end of dry season. They were dried and crushed to determine their chemical composition. The results showed that, with A. lebbeck , the levels of DM obtained at mid-season and the end that one, were higher (P 0.05). In addition, catechic tannins were not found in the leaves of S. siamea. However, the variations of this tannins type, observed in the leaves of L. leucocephala, M. lucida and A. lebbeck were not significant (p>0.05). On the other hand, the contents of gallic tannins measured in the leaves of S. siamea decreased at the end of the dry season (p<0.05). Conclusion : Finally, it appears that these species showed few variations in protein, cellulose and tannins throughout the dry season. Taking into account the results obtained, the shrub species studied could constitute good forage in supplementation of poor grass in the dry season. However, L. leucocephala and S. siamea should be used with much moderation for the feeding of ruminants, given the presence of gallic tannins in their leaves. Nevertheless, it would be important to study the digestibility of these forages in the dry season. Key words : legumes, fabaceae, rubiaceae, ruminants, tannins.

Foliar biomass production and litterfall pattern of five timber species in forest plantations of semi-arid lands of the northeastern Mexico

Background: Fodder shrubs and trees have both economic as well as ecological values in most extensive systems of arid and semiarid regions.&#x0D; Hypothesis: The litterfall represents an important way in maintaining the productivity of these ecosystems, and we hypothesized that its production pattern is related to the foliar biomass production, associated with seasons and species.&#x0D; Studied species: Acacia berlandieri, Acacia wrightii, Ebenopsis ebano, Havardia pallens and Helietta parvifolia .&#x0D; Study site and years of study: The foliar biomass was evaluated seasonally, from the dry weight of a representative branch of each species. The litterfall was collected every 15 days through litter traps installed under tree canopies, in experimental plantations of 30 years old, in the semi-arid zone of northeastern Mexico.&#x0D; Results: The foliar biomass values showed highly significant differences (P&lt; 0.01) among species as well as seasons, whereas leaf litter values presented highly significant differences (P&lt; 0.01) among seasons but not (P&gt; 0.05) among species. The maximum foliar biomass production was registered in summer by E. ebano (9,029 kg ha-1), while the lowest value (103 kg ha-1) was recorded in winter by A. wrightii . The greatest leaf litter accumulation was observed in winter (296 kg ha-1) by A. wrightii , and the lower value was recorded in spring, by E. ebano (97 kg ha-1). A significant linear correlation (R2= 68,79 %) was determined between accumulation of leaf litter and foliar biomass production in autumn.&#x0D; Concluisions: As conclusion, the leaf litter pattern can be related to the foliar biomass production, depending on the seasons and species. That constitutes a practical tool for the management of the forest ecosystems in semiarid areas.

Diversity and importance of local fodder tree and shrub resources in mixed farming systems of central Kenya

Locally available tree fodder resources are seldom considered in livestock feeding strategies despite their nutritional potential to supplement grass forages. Knowledge gaps on species availability and utilization may be the cause. This study surveyed 117 random farms locatedin humid (Githunguri and Lari) and drier parts (Kayatta) of central Kenya to identify fodder trees and shrubs diversity available to supplement existing livestock feeding options. Major forage and feed types used by farmers include napier grass (98.2%); maize and bean stover (85.7%); banana stover (60.5%), dairy meal (60.1%), hay (58.3%) and fodder trees (57.7%). A total of 60 fodder tree and shrub species were found on farm. Indigenous species comprised 65% of total richness but only 12% of the total abundance. The most common exotic and indigenous trees were Grevillea robusta and Persea americana, and Acacia tortilis and Terminalia brownii, respectively. Mean species richness per farm was 6.8 with significantly higher richness in Kayatta (10) compared to Lari and Githunguri (both 5.4, p < 0.05). Land size had a positive influence on total indigenous species richness and abundance on farms while the number of dairy cows had a negative influence. Findings confirm availability of diverse tree fodder trees to supplement current feeding options. However, where farms are small, farmers may require external feed sources as limited tree richness and abundance may not support profitable dairy farming.

A reliable and non-destructive method for estimating forage shrub cover and biomass in arid environments using digital vegetation charting technique

Despite the importance of fodder shrubs to small ruminant diets and production in arid and semi-arid ecosystems, they are often not considered when quantifying grazing land potential. This oversight is mainly due to the time consuming and costly traditional techniques used to estimate shrub biomass. The shrub fodder component should be measured to avoid underestimation of the carrying capacity of rangelands. In this study, we present a fast, reliable and non-destructive method to estimate canopy vegetation cover to obtain aboveground shrub biomass. The experiment was conducted under field conditions in northwest Syria, where seedlings of seven shrub species were monitored for one year: Atriplex leucoclada (Moq.) Boiss., A. halimus L., A. lentiformis (Torr.) S. Watson, A. canescens (Pursh) Nutt., A. nummularia Lindl., Salsola vermiculata L. and Haloxylon aphyllum (C.A. Meyer) Bunge. The experimental layout was a randomized complete block design with five replications. We explored the effectiveness of digital vegetation charting technique (DVCT) for estimating shrub canopy cover. Aboveground shrub biomass was clipped to estimate the dry matter (DM) weight per species and to determine its relationship to canopy cover. In this study, an estimate of greenness (percent green vegetation cover) was extracted by way of greenness algorithms. Simple linear regressions between vegetation cover and biomass for 210 plots were performed. The cover of the seven species differed (P < 0.01): A. leucoclada had the highest vegetation cover (56%) and H. aphyllum the lowest (7%). Vegetation cover and DM biomass were positively correlated (P < 0.01) with R-squared ranging from 0.66 (H. aphyllum) to 0.84 (S. vermiculata). Our method provided reasonable estimations of canopy coverage which could predict aboveground phytomass. We conclude that DVCT offers a rapid, reliable and consistent measurement of shrub cover and biomass provided that shrubs have open architecture. This study shows the potential of digital cameras and image processing to determine cover/biomass in a non-destructive, timely and cost efficient way.

Arbustivas forrajeras y ácidos grasos: estrategias para disminuir la producción de metano entérico en bovinos.

El objetivo de este trabajo fue analizar el uso de arbustos forrajeros y ácidos grasos poliinsaturados como estrategia nutricional para mitigar la producción de metano entérico en bovinos. Se hizo especial énfasis en el uso de la Tithonia diversifolia (Hemsl.) A. Gray (botón de oro), como especie con potencial antimetanogénico. La búsqueda de información bibliográ ca para llevar a cabo esta revisión se llevó a cabo durante los meses de junio a septiembre de 2015, mediante términos claves. El metano es un gas de efecto invernadero (GEI), el aumento en su concentración atmosférica, es causada principalmente por emisiones del sector agrícola y la industria, pero se estima también que una proporción es emitida por los rumiantes como producto de la fermentación entérica y anaeróbica de la dieta. Lo anterior causa un problema ambiental y de ine ciencia productiva en los sistemas ganaderos alrededor del mundo. Aunque existe controversia sobre el verdadero aporte de metano por los rumiantes y su incidencia sobre la problemática ambiental, la cantidad de emisiones se deben tratar de mitigar. El presente documento hace énfasis en la búsqueda de estrategias nutricionales, tales como la suplementación con especies arbustivas forrajeras y fuentes de ácidos grasos poliinsaturados, los cuales han demostrado tener potencial para mantener la e ciencia productiva del animal y una posible reducción en la síntesis de metano entérico.

English

Tagasaste (Chamaecytisus proliferus (L. fit.) Link var. palmensis (Christ) Hansen and Sunding is a perennial fodder shrub naturalized in a range of environments for its valuable forage traits. This research was aimed at evaluating the seasonal variation in chemical composition, bioactive compounds and antioxidant properties in edible biomass components (leaves, twigs, flowers, and pods) of tagasaste grown in a Mediterranean environment of Sardinia (Italy). Season influenced the composition of edible biomass and chemical composition and antioxidant capacity of leaves and twigs. On average, crude protein concentration was 200, 97 and 66 g kg-1 dry matter, in leaves, twigs and mature pods, respectively. Neutral and acid detergent fibre were high in twigs. In late summer, antioxidant capacity of leaves reached 44 mmol/100 g dry weight of Trolox equivalent and was correlated with the levels of total phenolics and flavonoids. Research highlights that the edible biomass of tagasaste is a high quality feed source available during the most critical forage shortage for rainfed farming systems of Mediterranean climatic areas. Key words: Bioactive compounds, forage quality, plant parts, polyphenols, tree lucerne.

The Photosynthesis, Na(+)/K(+) Homeostasis and Osmotic Adjustment of Atriplex canescens in Response to Salinity.

Atriplex canescens (fourwing saltbush) is a C4 perennial fodder shrub with excellent resistance to salinity. However, the mechanisms underlying the salt tolerance in A. canescens are poorly understood. In this study, 5-weeks-old A. canescens seedlings were treated with various concentrations of external NaCl (0–400 mM). The results showed that the growth of A. canescens seedlings was significantly stimulated by moderate salinity (100 mM NaCl) and unaffected by high salinity (200 or 400 mM NaCl). Furthermore, A. canescens seedlings showed higher photosynthetic capacity under NaCl treatments (except for 100 mM NaCl treatment) with significant increases in net photosynthetic rate and water use efficiency. Under saline conditions, the A. canescens seedlings accumulated more Na+ in either plant tissues or salt bladders, and also retained relatively constant K+ in leaf tissues and bladders by enhancing the selective transport capacity for K+ over Na+ (ST value) from stem to leaf and from leaf to bladder. External NaCl treatments on A. canescens seedlings had no adverse impact on leaf relative water content, and this resulted from lower leaf osmotic potential under the salinity conditions. The contribution of Na+ to the leaf osmotic potential (Ψs) was sharply enhanced from 2% in control plants to 49% in plants subjected to 400 mM NaCl. However, the contribution of K+ to Ψs showed a significant decrease from 34% (control) to 9% under 400 mM NaCl. Interestingly, concentrations of betaine and free proline showed significant increase in the leaves of A. canescens seedlings, these compatible solutes presented up to 12% of contribution to Ψs under high salinity. These findings suggest that, under saline environments, A. canescens is able to enhance photosynthetic capacity, increase Na+ accumulation in tissues and salt bladders, maintain relative K+ homeostasis in leaves, and use inorganic ions and compatible solutes for osmotic adjustment which may contribute to the improvement of water status in plant.

Les amendements du sol améliorent l’installation d’Opuntia ficus-indica (L.) Mill. dans les régions arides du sud-est du Maroc

In arid and semi-desert degraded areas of Morocco, many programs aiming at planting fodder shrubs have failed due to a lack of knowledge on effective methods for their successful establishment. Here we assessed the effects of gravel mulch (T1), TeraGel hydrophilic polymers (100g) (T2) and organic matter (5L peat) (T3), as soil amendments, on the establishment of prickly pear plant (Opuntia ficus-indica (L.) Mill.). T4 is considered as control. The study was conducted at the INRA experimental station in Errachidia, southern Morocco where cladodes were planted under natural water stress conditions on half moons. Changes in soil moisture were monitored for each treatment following rainfall. T2 had the highest soil water content during the first hours, but it decreased at a higher rate compared to T1 and T3. Cladode survival was significantly greater for T1 (100% ± 0.0) followed by T3 (94% ± 0.2), then T4 (72% ± 0.5) and T2 (67% ± 0.5). At the end of the experiment period, T1 and T3 grew 25% and 32% better than the control, respectively. Modular dynamics of cladodes (nopal) was also influenced by T1 and T3 ; the average number of cladodes after 34 months was of 18 units for T1 versus 11.8 units for the control. This study highlights the importance of using gravel mulch and organic matter in prickly pear plantations to improve the effectiveness of rainwater harvesting techniques in drylands.

Land sharing vs. land sparing in the dry Caribbean lowlands: A dung beetles’ perspective

Extensive cattle ranching is considered to be one of the major causes of environmental degradation particularly in tropical dry forest, one of the most threatened ecosystems worldwide. The transformation of extensive treeless pastures into intensive silvopastoral systems combining pastures, fodder shrubs, and trees has been promoted to rehabilitate degraded lands. This study was conducted to explore the influence of transforming extensive treeless cattle ranches into intensive silvopastoral systems and how this alters dung beetle diversity in a tropical dry forest located at Cesar river valley, Colombia. The study took place in three livestock farms, dung beetles were collected with baited pitfall traps in three land uses: forest, intensive silvopastoral systems and treeless pasture. A total of 5349 beetles belonging to 17 genera and 32 species, were collected. Forests had the highest species richness and abundance values, followed by intensive silvopastoral systems. The latter contained 61% of the native forest species and supported 36% more diversity than treeless pastures. Differences in diversity and composition were related mainly to canopy cover and soil cover. Conserving remaining dry forest fragments is crucial for preserving typical dry forest dung beetle assemblages in this region. Intensive silvopastoral systems complement the role of forests as reservoirs of biodiversity and contribute to the landscape-scale conservation of dung beetles. In this particular landscape and at the spatial scale that is relevant for dung beetles, intensive silvopastoral systems provide the benefits of both land sparing and land sharing.

Indigenous knowledge on the diversity, phenology, abundance and distribution of fodder trees and shrubs in the northeastern agro-pastoral areas of Ethiopia

The research was undertaken in northeastern Ethiopia with the objective of identifying potential indigenous fodder trees and shrubs (IFTSs) species, their feed value, abundance and distribution and characterizing their current utilization scenarios from the local people's perspective. Participatory Rapid Appraisal tools were employed and it was possible to identify 51 IFTSs from 23 different families. The foliage availability, abundance, distribution and niches of the IFTSs were found to vary across the different locations indicating the relative importance of each species in different places. Moreover foliage availability of the IFTSs varies in the different months of a year. Besides, 15 most important species were identified based on the number of respondents and from these, using pair wise ranking method, farmers could identify the top ten species which are more preferred by goats. In view of the diversified families of the IFTSs species and their wide distribution, they could enhance the productivity of the livestock sector, if indeed supported by further scientific investigations.

Organic Carbon and Alkalinity Increase in Topsoil After Rangeland Restoration Through Atriplex nummularia Plantation

AbstractThis research studied the impact of fodder shrub plantations (Atriplex nummularia Lindl.) on topsoil properties, with particular reference to organic carbon, nitrogen, and soluble salts, in the Marrakech region (central Morocco). The studied plantation interventions were carried out to rehabilitate degraded rangeland and to mitigate desertification. The field experiment was conducted by drawing seventeen 50‐m‐long transects designed according to the ecological patch–interpatch approach defined by the Landscape Function Analysis. The top soil (0–5 cm) was sampled in 134 microsites, covering the main patch and interpatch types in plantation and control plots. The following variables were determined: pH, carbonates, organic carbon, total nitrogen, electrical conductivity, and soluble ions (Na+, K+, Ca2+, Mg2+ Cl−, NO3−, SO42− and PO43−). Statistical analyses were carried out to analyse changes between sites and between patch types. Most of the studied properties were strongly affected by the spatial pattern defined by the plantation, particularly when the sites with higher biomass production were considered. Organic carbon increased by around 63% and 117% when the under canopy patches were compared, respectively, to the between‐plants interpatches and to the control plots, a strong positive effect considering the aridity of the study area. On the other hand, a stronger increase was detected under canopy for most soluble salts and sodium adsorption rate. On average, the latter increased by 350% and up to 450% under the best developed plants, a stronger impact than observed in previous research, highlighting the very strong plant effect on the soil surface alkalinity. Copyright © 2015 John Wiley &amp; Sons, Ltd.

Effect of inoculum source (Sheep or Goat) on in vitro gas production and rumen fermentation parameters of some fodder shrubs in northern Tunisia

In order to ensure nutritional characterization of some fodder shrubs and test the effect of inoculum source (sheep and goats) on their digestibility. Four shrubs “Acacia cyanophylla, Atriplex halimus, Opuntia ficus-indica. Var.inermis(cactus) and Medicago arborea” were tested in vitro by incubating them firstly into the rumen fluid of sheep then into goat’s inoculums. The evaluation included chemical composition, total gas production (CO2 and CH4), the prediction of organic matter digestibility (OMD), metabolizable energy (ME), the concentration of total volatile fatty acids (SCFA) and metering ammonia nitrogen (NH3-N). Ruminal fermentation of Opuntia ficus-indica and Medicago arborea have identified more total gas amonts than Atriplex halimus and Acacia cyanophylla. Digestibility of organic matter, metabolisable energy and the concentration of total volatil fatty acids were higher in the case of Opuntia ficus-indica compared to other shrubs. The lowest values were recorded in the Atriplex halimus. The concentration of ammonia nitrogen (NH3-N), it turned out that Opuntia ficus-indica is the food with less protein concentration (140 and 270.66 mmol/syringe) respectively for sheep and goats. In against part, the Medicago arborea is presented as a good protein source recording of ammonia nitrogen concentration (214.67 mmol/syringe) into the sheep’s rumen and (494.67 mmol/syringe) into the goats inoculum. The source of the inoculum showed a highly significant effect (p &gt; 0.05).

There is more in fodder trees than their nutritional values: local valuation of indigenous fodder trees and shrubs by pastoral and agrarian communities in northern Ethiopia

This research was undertaken to understand variation in local knowledge between two ethnic/livelihood, gender, and age groups on indigenous fodder trees and shrubs (IFTS) and correlate local criteria-based valuation with laboratory-based valuation. The study involved 160 respondents, formal interviews, species identification tests, and scoring of trees. Fodder samples taken from the top 20 preferred species were scanned using NIRS (Near Infrared Reflectance Spectroscopy) and their nutritive value was assessed. ANOVA, non-parametric Kruskal–Wallis median comparison test, and Spearman's rank correlation were used to analyze the data. Local people used diverse criteria falling under three categories: animal-based (5), plant-based (4), and multipurpose criteria (11). Knowledge of fodder trees varied significantly (P < 0.05) between the two ethnic/livelihood groups and gender, but not between age groups. Ziziphus spina-christi and Cordia gharaf were the most locally preferred species for both ethnic/livelihood groups. Local criteria and NIRS-based valuation of IFTS were weakly correlated, suggesting that species selected only on their nutritive merit may not be preferred and adopted by farmers and pastoralists.

A Strategy for Scaling-Up Intensive Silvopastoral Systems in Colombia

Silvopastoral systems (SPS) enhance milk and meat production and are instrumental for the productive rehabilitation of degraded lands. Intensive silvopastoral systems (ISPS) combine fodder shrubs planted at high densities (>10,000 plants ha−1), trees and pastures. Scaling-up such systems requires incentives to address financial and knowledge barriers. In Colombia, the strategy for scaling-up SPS has combined five elements. First, participatory research on real farms contributed to optimize SPS in different agroecosystems and strengthened a network of pilot farms open to research and peer-to-peer technology transfer. Second, capacity building, training, and outreach activities spread the principles of SPS among farmers, field workers, researchers, extension workers, and policy makers. Third, pilot projects explored the role of incentives such as Payment for Environmental Services (PES), technical assistance, soft loans and bonus prices, in spreading SPS. Fourth, successful pilot projects were instrumental in influencing the livestock sector as well as the public policy agenda. Fifth, currently, large-scale projects aimed at mainstreaming SPS are applying the lessons learned in order to achieve landscape-scale benefits, enhance climate change adaptation and mitigation, and introduce SPS products to green markets. Recently, innovation networks have contributed to speed up the adaptation of SPS in different environmental and socioeconomic contexts.

Impact of soil erosion associated factors on available feed resources for free-ranging cattle at three altitude regions: Measurements and perceptions

The study was conducted to assess the status and trends of soil erosion and relate the perceptions of farmers on cattle productivity and botanical indicators to measured ecological conditions of rangelands in three altitude regions of southwest Ethiopia. A total of 342 farmers were interviewed. In addition, the ecological condition of rangelands was assessed. Severe soil erosion, ranked as the primary restriction to free-ranging livestock, occurred predominantly in the lower altitude region (LAR) (P < 0.05). More farmers in LAR witnessed an inadequacy of palatable plant biomass, grazable pasture as well as increased gully formation and expansion, which are strong indicators of soil erosion (P < 0.001). In addition to a decrease in grass cover and productivity of cattle, botanical composition, species richness and grazing capacity of herbaceous plants, less fodder trees and shrubs were observed (P < 0.05). There was a corresponding increase in the percentage of bare ground and soil erosion status along the degradation gradients (P < 0.05). The reported shift in botanical composition, and especially encroachment of invading plant species, can be attributed to soil erosion (P < 0.001). The results suggest that erosion is associated with reduced availability of feed resources and is related to altitude variation.

Effects of restoration actions on soil and landscape functions: Atriplex nummularia L. plantations in Ouled Dlim (Central Morocco)

Fodder shrub plantations (Atriplex nummularia L.) were extensively introduced in dryland areas of central Morocco (Marrakech province, Ouled Dlim and Ouled Nejim municipalities) to rehabilitate degraded rangeland and to mitigate desertification processes. These interventions deeply modified the original rural landscape, characterized by sparse vegetation cover in relation to a long history of intense grazing and subsistence cropping, and by soils prone to surface crusting and to high runoff generation. The Landscape Function Analysis (LFA) was applied to study the effects of the Atriplex plantation on soil and landscape functions. The LFA landscape functional indicators (Landscape Organization Index, LOI; Patch Area Index, PAI; Number of Patches, NP; Patch Number Index, PNI) were measured along seventeen 50-m-long transects, established to compare five “actions” (CR, Cropped; GR, Grazed; MA, Mature plantation; YA-1, Young plantation with moderate biomass development; YA-2, Young plantation with good biomass development). The LFA soil surface indicators, and the related NC (Nutrient Cycling) and IR (Infiltration/Runoff) indices were assessed in the observed ecological patches and inter-patches, for a total number of 157 microsites. Biomass production was measured in all the studied plantations. Multiple group comparison analysis was performed to compare the mean values of the LFA indices according to action and patch types. Correlation analysis was carried out to study the relationships between biomass and functional indices. The results obtained show that the young and well developed plantations have the stronger impacts on all the LFA indices and that the plantation effects are mostly linked to the localized synergistic effect of the plant–furrow association. In the study area the LFA provided an effective metric to assess the relative effectiveness of the actions compared.

Land restoration by fodder shrubs in a semi-arid agro-pastoral area of Morocco. Effects on soils

Abstract The present study assesses the effects of Atriplex nummularia Lindl. growth on soil chemical properties in a semi-arid area. The area is located in the Marrakech province (Morocco), in a degraded agropastoral region subjected to soil restoration actions based on fodder shrub plantations. Three plantations of different age (1995, 2000, 2001), conducted in three different sites, were investigated. In each site, three plots with different degree of plant development (Good, Medium, Poor), were chosen. Three under-canopy (Uc) and three between-plants (Bp) minipits were sampled (0–10 cm and 10–20 cm) and analysed in each plot, for a total number of 54 minipits. Statistic analysis was carried out to check the significance of the observed Uc–Bp average differences. A significant increase under canopy was observed in soil Sodium Adsorption Ratio (SAR; + 139%) and OC (+ 32%) in the top layer (0–10 cm). The overall effects of the plantations on soil quality are discussed.

Merits of the fat-tailed Barbarine sheep raised in different production systems in Tunisia: digestive, productive and reproductive characteristics

Barbarine sheep is the dominant breed in Tunisia. This fat-tailed breed present in all production systems is characterised by metabolic and digestive adaptation to the contrasting environment conditions prevailing in the country (heat stress, water deprivation, salinity etc.). The fat tail (1.5 to 7kg) is an energy reservoir that is used in periods of feed scarcity. Moreover, the rumen of this breed harbours a microflora enabling it to valorize low-quality roughages and native range vegetation. Barbarine sheep could make benefit from a wide range of local feed resources like fodder shrubs (e.g. cactus and oldman saltbushes), tannin-containing shrubs (e.g. Acacia cyanophylla) and agro-industrial by-products (e.g. olive cake, bran etc. conserved in the form of feed blocks or pellets). It has a very shallow anoestrous, the intensity of which is dependant upon nutrition conditions rather than day length as temperate breeds. Productive and reproductive performances of late pregnant-early suckling, pre-mating ewes and also rams of this breed are not affected when some alternative feed resources replace common feedstuffs which are expensive and cannot afford regularly to smallholders. In brief, the merits of the Barbarine sheep in the production systems and other main adaptive mechanisms of this breed are discussed in this paper. The prospective of Barbarine sheep husbandry in the system dynamics, climate change and the evolution of the socioeconomic context are also envisaged.

Planted saltbush (Atriplex nummularia) and its value for birds in farming landscapes of the South Australian Murray Mallee

Summary In the fragmented agricultural landscapes of temperate southern Australia, broad-scale revegetation is underway to address multiple natural resource management issues. In particular, commercially-driven fodder shrub plantings are increasingly being established on non-saline land to fill the summer-autumn feed gap in grazing systems. Little is known of the contribution that these and other planted woody perennial systems make to biodiversity conservation in multifunctional landscapes. In order to address this knowledge gap, a study was conducted in the southern Murray Mallee region of South Australia. Selected ecological indicators, including plant and bird communities, were sampled in spring 2008 and autumn 2009 in five planted saltbush sites and nearby areas of remnant vegetation and improved pasture. In general, remnant vegetation sites had higher biodiversity values than saltbush and pasture sites. Saltbush sites contained a diverse range of plants and birds, including a number of threatened bird species not found in adjacent pasture sites. Plant and bird communities showed significant variation across saltbush, pasture and remnant treatments and significant differences between seasons. This study demonstrates that saltbush plantings can provide at least partial habitat for some native biota within a highly modified agricultural landscape. Further research is being conducted on the way in which biota, such as birds, use available resources in these dynamic ecosystems. An examination of the effects of grazing on biodiversity in saltbush would improve the ability of landholders and regional natural resource management agencies in making informed land management decisions.

Short- and medium-term response of Atriplex halimus L. to repeated seasonal grazing in south-eastern Spain

Atriplex halimus L. is a valuable fodder shrub that has been widely used in arid Mediterranean regions. However, its response to several cumulative years of grazing management remains uncertain. Accordingly, we conducted a three-year experiment in south-eastern Spain to analyze the influence of repeated seasonal (winter-spring) sheep browsing on young A. halimus plants. Shrub growth, fodder and wood production, plant compactness and shoot moisture content were assessed through regular monitoring of the size of shrubs, sampling of summer shoots, and destructive procedures at the end of the experiment. Shrubs were on two closely located sites but where soil quality and water availability were different. At the better location, browsed shrubs grew less and were significantly smaller ( P < 0.001) than the non-browsed saltbushes. In contrast, differences between groups were minimal where the growth conditions were poorer. In all cases, shrubs resprouted vigorously and maintained fodder production throughout the experiment. Browsing affected shrub structure, resulting in smaller but more compact plants (2.20 vs. 1.24 g dm −3, P < 0.001), but their proportion of fodder remained similar. The spring grazing increased shrub-shoot moisture content in the summer (62.5% vs. 56.0%, P < 0.001). Overall, this species responded very positively to repeated seasonal grazing.