Scrub Woodland Research Articles

Composition and activity of soil microbial communities in native and non-native vegetation of southern California

The proliferation of non-native plant species in novel habitats has altered plant community diversity, ecosystem carbon (C) and nutrient cycling, and disturbance regimes worldwide. However, the impacts of non-native plants on soil microbial community composition and activity are still poorly known, especially in semi-arid woodlands. Here we utilized next generation sequencing (16S rRNA sequencing of the V3-V4 regions) and measurements of microbial activity (respiration, net N mineralization, and enzyme assays) to determine how soil microbial composition and activity varied between native and non-native vegetation patches in coastal sage scrub (CSS) woodlands. We sampled eight CSS sites and collected topsoil (0–10 cm) samples from six paired native and non-native vegetation patches at each site. Native patches had significantly (p < 0.05) higher vegetation cover, dissolved organic C (DOC), and dissolved inorganic nitrogen (DIN) concentrations than non-native patches. β-glucosidase activity was significantly higher (ca. 10 nM g−2 h−1) and peroxidase activity was significantly lower (ca. 60 nM g−2 h−1) in non-native vegetation, while rates of net N mineralization and nitrification, phosphatase and NAGase activities, and respiration were not significantly different in native and non-native vegetation but were positively correlated with total soil C and N (r > 0.60; p < 0.05). Bacterial alpha- and beta-diversity were not significantly different (p > 0.05) between native and non-native patches; however, bacteria/archaea in the phyla Gemmatimonadota, Planctomycetota, Armatimonadota, Fibrobacterota, Thermoplasmatota, and Entotheonellaeota were over-expressed in non-native patches. Within these phyla there were 20 orders that were differentially expressed in native or non-native vegetation, and more than half (60 %) had significantly higher relative abundance in native vegetation. Our results indicate that the expansion of non-native vegetation in semi-arid woodlands significantly alters soil C and N, which feeds back on microbial activity and community composition.

Digital Examination of Vegetation Changes in River Floodplain Wetlands Based on Remote Sensing Images: A Case Study Based on the Downstream Section of Hailar River

The Hailar River is an important river in the Inner Mongolia Autonomous Region, China. It plays an extremely important role in maintaining the ecological balance of the region. However, in recent decades, the Hailar River and its surrounding areas have been developed at a high rate and its wetland resources have faced various threats. In this study, vegetation changes in the Hailar River wetlands were analyzed using remote sensing data from the Landsat TM (1987, 2001, and 2010) and Landsat OLI-TIRS (2019) satellites. A vegetation change model was developed using Matlab software to assess vegetation changes in the area. There were significant changes in the wetland vegetation of the lower Hailar River study site between 1987 and 2019. There was an increase in open sand habitat with a sparse vegetation area of 1.08 km2, a decrease in grassland area of 13.17 km2, and an increase in the forest area of 15.91 km2. The spatial distribution of the normalized difference vegetation index (NDVI) varied across the study site and was high overall. The vegetation types varied with distance from the river. There are two possible explanations for positive and negative vegetation change trends. In areas where the water supply is sufficient and relatively stable, the cover of forest vegetation was gradually increasing and the herbaceous plant community is gradually evolving into a scrub woodland plant community. In areas where the water supply is lacking, there are changes in the sense of a decrease of forest vegetation and an increase of open sand habitat with sparse vegetation. Therefore, this study suggests that the existing wetlands should be protected, used wisely, and developed rationally to provide sustainable resources for the next generation.

How are pollination and seed dispersal modes in Cerrado related to stratification? Trends in a cerrado sensu stricto woodland in southeastern Brazil, and a comparison with Neotropical forests

A comprehensive census of a hectare of cerrado s.s. in southeastern Brazil, a small-tree and scrub woodland physiognomy, allowed the evaluation of whether pollination and dispersal modes are correlated with the stratification of the vegetation and if so, in what way. Generalist pollination, and pollination by small bees, as well as ornithophily and anemophily were more frequent in the lower layers (ground and scrub), while species pollinated by large bees and beetles are more or less equally distributed among the ground, scrub and tree layers. The three nocturnal pollination modes, phalenophily, sphingophily, and chiropterophily indicated a preference for the upper layers (tree and scrub). Zoochory predominated in the tree layer, but autochory increased towards the ground at the expense of anemochory and zoochory. We discuss possible reasons for the height distribution of pollination and seed dispersal modes and compare the situation in Cerrado with other Neotropical forests.

A Neolithic palaeo-catena for the Xagħra Upper Coralline Limestone plateau of Gozo, Malta, and its implications for past soil development and land use

Geoarchaeological survey on the island of Gozo combined with test excavations and new chronometric dating of two Neolithic temple sites at Santa Verna and Ġgantija on the Xagħra plateau have revealed well-preserved buried soils which tell a new story of soil development and change for the early-mid-Holocene period. Micromorphological analysis has suggested that the earlier Neolithic climax soil type was a thick, well-developed, humic and clay-enriched argillic brown Mediterranean soil. With human intervention on the Xagħra Upper Coralline Limestone plateau from at least the early 4th millennium BCE, the trajectory of soil development quickly changed. Radical soil change was marked by the removal of scrub woodland, then consequent poorer organic status and soil thinning, and rubefication and calcification, no doubt exacerbated by Neolithic agricultural activities and a more general longer-term aridification trend. The beginnings of this transitional brown to red Mediterranean soil change process has been observed at Santa Verna temple by the early 4th millennium BCE, and appears to be much further advanced by the time of the latter use of Ġgantija temple in the early-mid-3rd millennium BCE. There is also evidence of attempts at amending these deteriorating soils during this period and into the 2nd millennium BCE, a practice which probably underpinned the viability of later Neolithic agricultural society in the Maltese Islands. The changes observed ultimately resulted in the creation of the thin, xeric, red Mediterranean soils on the Coralline Limestone mesa plateaux which are typical of much of Gozo and Malta today.

Vegetation management influences habitat use by mammalian herbivores in shrub-encroached grassy woodland

Context Restoration of disturbed vegetation communities commonly involves altering vegetation composition and structure, attributes that can influence the suitability of habitat for fauna. Feedbacks may occur whereby changes to the vegetation affect mammalian herbivores, and unintended changes may prevent managers from achieving conservation goals. Aims To understand how vegetation management affects habitat use by five mammalian herbivores, namely eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor), common wombat (Vombatus ursinus), European rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus). Methods A management experiment (mechanical slashing of the encroaching shrub Leptospermum laevigatum) at Wilsons Promontory National Park, Australia, created slashed swales in addition to untreated dune and scrub woodland. In each vegetation stratum, we estimated the cover of L. laevigatum and quantified herbivore abundance by counting the standing crop of faecal pellets. Key results Relative to untreated vegetation, mechanical slashing of L. laevigatum substantially reduced cover of this species above 200 cm, but increased its cover below 30 cm. On the basis of faecal-pellet counts, multispecies use of managed and unmanaged parts of the landscape differed substantially, with the differences principally driven by higher abundance of European rabbits and eastern grey kangaroos at slashed sites. Conclusions The responses of three grazing species (kangaroo, rabbits and wombats) to vegetation management were predicted well by prior knowledge of diet and habitat preferences. This was not the case for the browser (swamp wallaby), nor for the grazer that consumes substantial amounts of browse in the study area (hog deer), and additional knowledge of the processes underlying their responses to vegetation change is required. Implications Our findings highlighted that vegetation management can influence herbivore abundances in the managed system. An improved understanding of these associations will allow vegetation management plans to incorporate herbivore responses.

Distribution of cryptic shrew species of the genus Sorex (Mammalia) on the plain between the Don and Kuban rivers as inferred by molecular markers

Microsatellite and mtDNA markers have been used to identify two pairs of cryptic species Sorex araneus L. (Sorex satunini Ogn.) and Sorex minutus L. (S. volnuchini Ogn.). The new data were obtained on the distribution of these species on the plain between the Don and Kuban rivers. The shrew S. volnuchini and Caucasian mole are distributed on the plain areas up to the Eya River. The endemic species of the Caucasus, the shrews S. satunini and S. volnuchini, are widely distributed across the valleys alongside small streams on the steppe plain. Both species are most abundant on thick grasslands, bushy scrub, and deciduous woodlands. They don't show any clear differences in habitat preferences.

Habitat use by Nightingales in a scrub–woodland mosaic in central England

SUMMARY Capsule Nightingales Luscinia megarhynchos with song territories in scrub vegetation also used adjacent woodland. Aims To examine spatial use by Nightingales of vegetation mosaics and associated selection of vegetation height classes. Methods We examined habitat selection by male Nightingales through territory mapping and radiotracking within a mosaic of dry scrub and woodland adjacent to water-filled gravel pits in eastern England. Results Fourteen song territories were exclusively in scrub, 2 were exclusively in woodland, and 13 comprised both habitat types. Densities were greatest in scrub vegetation of 3–5 m height. Best-supported models for territory density indicated the importance of considering optimal vegetation height within management prescriptions. Despite song territories being in scrub, kernel home-ranges of all radiotracked Nightingales contained areas of mature trees. Birds also spent more time there than expected based on availability of woodland within kernels. Conclusions Habitat quality has been implicated in the decline of Nightingales in lowland woodland in Britain (and an associated increase in the proportion found in scrub). Our results indicate that woodland habitat characteristics provide resources for Nightingales with song territories located in dry scrub and may be a factor in territory establishment, and are therefore relevant for conservation practitioners at such sites.

The summertime Boreal forest field measurement intensive (HUMPPA-COPEC-2010): an overview of meteorological and chemical influences

Abstract. This paper describes the background, instrumentation, goals, and the regional influences on the HUMPPA-COPEC intensive field measurement campaign, conducted at the Boreal forest research station SMEAR II (Station for Measuring Ecosystem-Atmosphere Relation) in Hyytiälä, Finland from 12 July–12 August 2010. The prevailing meteorological conditions during the campaign are examined and contrasted with those of the past six years. Back trajectory analyses show that meteorological conditions at the site in 2010 were characterized by a higher proportion of southerly flow than in the other years studied. As a result the summer of 2010 was anomalously warm and high in ozone making the campaign relevant for the analysis of possible future climates. A comprehensive land use analysis, provided on both 5 and 50 km scales, shows that the main vegetation types surrounding the site on both the regional and local scales are: coniferous forest (Scots pine and/or Norway spruce); mixed forest (Birch and conifers); and woodland scrub (e.g. Willows, Aspen); indicating that the campaign results can be taken as representative of the Boreal forest ecosystem. In addition to the influence of biogenic emissions, the measurement site was occasionally impacted by sources other than vegetation. Specific tracers have been used here to identify the time periods when such sources have impacted the site namely: biomass burning (acetonitrile and CO), urban anthropogenic pollution (pentane and SO2) and the nearby Korkeakoski sawmill (enantiomeric ratio of chiral monoterpenes). None of these sources dominated the study period, allowing the Boreal forest summertime emissions to be assessed and contrasted with various other source signatures.

Suspect burial excavation procedure: A cautionary tale

Geographic location, time of reporting and need for rapid evaluation contributed to a lack of intelligence concerning a suspect burial site in scrub woodland (∼15 km from the last known location of a missing person) in Northern Ireland. Police received reports of a subsiding ‘grave’, which was evaluated positively using GPR and victim recovery dogs (VRD). After 24 h work, archaeological excavation showed a vertical-sided, stepped excavation on undisturbed clay with no inhumation. Subsequent research showed the feature to be an engineering trial pit. The GPR response was a water table and rocks, VRD were possibly reacting to disturbed ground. The work serves as a demonstration of good archaeological practice in suspect burial excavation, following a lack of landscape evaluation and poor overall intelligence.

The influence of habitat and landscape on small mammals in Estonian coastal wetlands

We investigated the influence of habitat type and landscape composition on small mammal relative abundance and diversity in coastal wetlands in western Estonia. Seventy live-trap lines in eight representative habitats, across six wetlands revealed seven species. The most diverse habitats were reed bed and scrub woodland, whereas tall grasslands had the highest biomass. Short grass was low in species richness and relative abundance. Small mammal relative abundance, richness, and biomass were positively correlated with tall grass and mosaic habitats and negatively correlated with lower shore habitats and bare ground. Our study indicates potential nature conservation conflicts between small mammals and other biodiversity priorities in wetlands.

Long-term deer exclusion in yew-wood and oakwood habitats in southwest Ireland: Natural regeneration and stand dynamics

Woodland dominated by Taxus baccata is one of the rarest of European woodland types and has priority habitat status under Annex I of the EU Habitats Directive, yet little is known about its stand dynamics or the effects of long-term grazing. The abundance of naturally regenerating seedlings and saplings was monitored over a 32-year period in exclosures in a yew-wood and a neighbouring oakwood in the Killarney National Park, southwest Ireland. Both woods are heavily grazed by introduced sika deer ( Cervus nippon). Mortality, recruitment and growth of adult trees were monitored over a 20-year period. Comparison was made with unfenced plots adjacent to each of the exclosures. Regeneration in the yew-wood exclosures was chiefly by Ilex aquifolium, Sorbus aucuparia and Fraxinus excelsior. No Taxus baccata saplings were recorded and seedlings of this species were very rare throughout the duration of the experiment. Taxus baccata trees which died during the 20-year monitoring period were significantly smaller than those which survived, indicating that self-thinning is occurring and the wood in its present form may be of relatively recent origins. Changes in adult tree species composition suggest that yew woodland in Ireland may develop from a yew-hazel scrub woodland sere. A variety of species regenerated in the oakwood exclosures, including Taxus baccata, and dense holly thickets formed in several areas. Quercus petraea failed to regenerate beneath the oak canopy. We conclude that chronic heavy grazing in the Killarney woodlands strongly influences the natural regeneration of several tree species. Research into the scientific manipulation of grazing levels in temperate woodlands is required. However, grazing intensity is not the only factor affecting regeneration, canopy conditions in particular are also likely to be of high significance, and this should be reflected in management plans.

Water Environments: Anthropogenic Pressures and Ecosystem Changes in the Atlantic Drainage Basins of Brazil

Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.

Water Environments: Anthropogenic Pressures and Ecosystem Changes in the Atlantic Drainage Basins of Brazil

Densely occupied drainage basins and coastal zones in developing countries that are facing economic growth are likely to suffer from moderate to severe environmental impacts regarding different issues. The catchment basins draining towards the Atlantic coast from northeastern to southern Brazil include a wide range of climatic zones and diverse ecosystems. Within its borders lies the Atlantic rain forest, significant extensions of semiarid thorn forests (caatinga), vast tree and scrub woodlands (cerrado) and most of the 6670 km of the Brazilian coast and its marine ecosystems. In recent decades, human activities have increasingly advanced over these natural resources. Littoralization has imposed a burden on coastal habitats and communities. Most of the native vegetation of the cerrado and caatinga was removed and only 7% of the original Atlantic rainforest still exists. Estuaries, bays and coastal lagoons have been irreversibly damaged. Land uses, damming and water diversion have become the major driving forces for habitat loss and aquatic ecosystem modification. Regardless of the contrast between the drought-affected northeastern Brazil and the much more prosperous and industrialized southeastern/southern Brazil, the impacts on habitat and communities were found equally severe in both cases. Attempts to halt environmental degradation have not been effective. Instead of focusing on natural resources separately, it is suggested that more integrated environmental policies that focus on aquatic ecosystems integrity are introduced.

Vegetation history of mid- to western Ireland in the 2nd millennium a.d.; fresh evidence from tephra-dated palynological investigations

The historic Icelandic tephra layers, from Hekla in a.d. 1104 and Oraefajokull in a.d. 1362 that have been found in four peat profiles obtained from lowland and upland mid to western Irish bogs, provide the dating for high-resolution palynological investigations of regional land use over the last thousand years. Marginal agriculture is investigated through the study of an upland blanket peat and a lowland Atlantic blanket peat. At the lowland site, the landscape has been altered, primarily by removal of hazel scrub, while in the uplands, there has been little scrub woodland throughout the last millennium. Pastoral agriculture has a long, unbroken history at both sites, with a short period of arable agriculture, dated to the early 19th century, detected in the uplands. At the two lowland sites, changes in land use associated with medieval monastic and secular activity were similar but not synchronous. The a.d. 1362 tephra in one lowland profile provides high-resolution dating of the palynological evidence for agricultural collapse in the aftermath of the Black Death. The palynological evidence of late medieval woodland clearance is contrasted with the written record. The effects of 19th century population expansion on land use are considered. A synthesis of regional land use in Ireland during the last thousand years is presented.

Woody species diversity of four sacred groves in the Pondicherry region of South India

Plant wealth and diversity of four sacred groves – twoanthropogenic stands and two natural forest patches – along the southeastcoast of India adjoining Pondicherry was studied. A total of 111species, belonging to 103 genera in 53 families, were recorded from thefour sites, which together measure 15.6 ha. The number of woody species (girth at breast height(gbh) ≤20 cm) was 20 each in Keezbuvanagiri (KBG) andKilialamman (KLM) grove, followed by 13 in Periyakattupalayam (PKP) and 15in Periyamudaliar chavadi (PMC). Based on the important value index (IVI), PMCgrove is an association of Aglaia elaeagnoidea,Borassus flabellifer and Pterospermumsuberifolium. A two-layered forest structure resembling tropical dryevergreen forest (TDEF) was found there. Stratification was obscured in the KBGgrove, as the scrub species were abundant, indicating a scrub woodland formation.PKP and KLM were characterised by the abundance of a few species. The presenceof a stout liana of Secamone emetica (gbh 35cm), the robustness of Cretaeva magna (gbh 220cm), Syzigium cumini (gbh 207.45cm), P. suberifolium (gbh 128.7cm) and Tamarindus indica (gbh 250cm), and survival of evergreen species like A.elaeagnoidea and Pamburus missionis isbotanically significant; Polyalthia suberosa is a raretaxon found only within the groves. The persistence of the groves until thepresent time is a testimony to the sacred grove status enjoyed by them.

The nature and diversity of neotropical savanna vegetation with particular reference to the Brazilian cerrados

Summary 1. The South and Middle American tropics contain the world's largest area of moist savanna. Despite an apparent uniformity in appearance, floristic groupings can be detected and four zones are provisionally outlined with a number of character‐ istic plants.2. Although current knowledge of their bio‐ geography and palaeoecology is scattered and incomplete, it is evident that there have been significant changes throughout the neotropics since the glacial maximum.3. The largest and most significant savanna formations are the Brazilian cerrados, which occupy nearly 23% of that country, an area equivalent to that of western Europe. The cerrados range from savanna woodlands (cerradão), through progres‐ sively less arboreal formations (cerrado), to nearly treeless grasslands (campo). A number of adjoining vegetation formations are closely related, including evergreen and deciduous forests, scrub woodlands and wetlands.4. Until the last decade, the biological diversity of the neotropical savannas was thought to be limited since, structurally, they appeared to form a relatively simple mosaic of repeated physiognomic units. New evidence reveals a rich diversity of tree, shrub and herbaceous plants in a continuously changing spatial pattern. Such diversity reflects the great area of the biome, together with local differences in topography and drainage, soil conditions and fire frequency.5. Research on the dynamic processes affecting savannas is of increasing importance and urgency given the potential value of the area that is still relatively undisturbed (about 50% of the original, but with less than 2% having federal reserve status) and the pace of current conversion to different forms of land use.

Habitat utilization by the arboreal boa Corallus grenadensis in two ecologically disparate habitats on Grenada

Abstract Habitat utilization by the arboreal boid Corallus grenadensis was studied at two ecologically disparate sites on the West Indian island of Grenada: one devoted largely to agriculture, the other largely devoid of agricultural activity. Small snakes (&lt; 600 mm SVL) were most often encountered in uncultivated scrub woodland at both sites; large snakes (&gt;1100 mm SVL) were encountered most often in fruit trees at one site and in mangroves at the other. Snakes of medium size (600-1100 mm SVL) occurred in both kinds of habitat. These size classes correspond to an ontogenetic shift in diet (lizards to mammals), and this is associated with a corresponding shift in habitat utilization.

Use and conservation of woody vegetation by the Batemi of Ngorongoro District, Tanzania

The Batemi, agropastoralists of north-central Tanzania, inhabit a landscape of savanna and scrub woodland. We identified 61 species of woody plants used by the Batemi for 19 types of items. The reports indicated 39 species are used for construction, 19 species for cultural artifacts, 23 for firewood and 6 live trees for fences, boundaries and shade. The Batemi have extensive knowledge of species habitat and distinctive management strategies for woody vegetation, particularly for the well-forested irrigation channels and spring sources. To date, a total of 90 species of woody plants have been identified as useful to the Batemi. Compared to the total number of species found within the study area, the Batemi use 79% of woody plant species in the area.

Natural volatile organic compound emission rate estimates for U.S. woodland landscapes

Volatile organic compound (VOC) emission rate factors are estimated for 49 tree genera based on a review of foliar emission rate measurements. Foliar VOC emissions are grouped into three categories: isoprene, monoterpenes and other VOCs. Typical emission rates at a leaf temperature of 30°C and a light intensity of 1000 μmol m −2 s −1 range from <0.1 to 70 μg C g −1 h −1 for isoprene, <0.1 to 3 μg C g −1 h −1 for monoterpenes, and < 0.5 to 5 μg C g −1 h −1 for other VOCs. Isoprene emission factors are given for biogenic emission models that incorporate canopy shading effects and thus require leaf-level emission rates and for emission models that do not include a canopy model and therefore require branch-level isoprene emission factors which already account for some shading. Landscape-level emission rates are estimated by combining emission rate factors determined for tree genera with species composition and foliar mass data. Landscape emission rate factors are determined for each of the 91 woodland landscapes in the high resolution (1.1 km) gridded land-cover database compiled by the EROS Data Center (EDC) from satellite and ancillary data. This database covers the entire contiguous United States of America. Landscape emission rates are also be determined using gridded tree distribution data, based on aerial photographs and ground measurements, such as that available in the U.S. Forest Service (USES) Easlwide Forest Inventory Database (EFID). Emission rates are reported for 41 of the 65 tree genera in the EFID including all of the most common genera. Total VOC emission rate factors for the 91 EDC woodland-cover types range from 0.8 to 11 mg C m −2 h −1 at a standard condition of 30°C and 1000 μmol m −2 s −1 . These landscape factors are based on branch-level emission factors and thus already incorporate canopy shading effects. The estimated fluxes of isoprene and monoterpenes are in relatively good agreement with field measurements of area-averaged fluxes if accurate species composition data (e.g. from the EFID) are available. Total VOC emission rate estimates range from 0.8 to 4.3 mg C m −2 h −1 for scrub woodlands and 2.2 to 11 mg C m −2 h −1 for mixed deciduous/coniferous woodlands. The chemical composition of the VOC flux ranges from 8 to 91 isoprene, 1 to 56% for monoterpenes and 8 to 73% for other VOC. On an area-weighted basis, the U.S. average total VOC emission rate factor of 5.1 mg m −2 h −1 for all woodlands is comprised of 58% isoprene, 18% monoterpenes and 24% other VOC. In comparison to previous estimates, these emission rates are generally higher for isoprene and lower for monoterpenes.

Soil phosphorus in a managed Mediterranean woodland ecosystem: herbage response and cattle grazing effects

A study of soil-plant relations in scrub woodlands on terra rossa soil in Israel, examined the following hypotheses: (a) that herbaceous plant growth on terra rossa is limited by phosphorus deficiency; (b) that shrub control and tree thinning can release available P for use by herbaceous vegetation; (c) that cattle fed P-rich poultry litter as a nitrogen supplement, can increase the available P level in the soil by recycling excess P through their excrements. Soil available P (bicarbonate-soluble) content was 4–9 mg kg −1 soil in the surface 15 cm soil layer and 2–3 mg kg −1 soil in the deeper 15–30 cm layer. A bioassay showed that plant growth was restricted when P concentration was less than 11 mg P per kg soil. Addition of nitrogen did not increase herbaceous yield, Neither thinning of trees nor shrub control using herbicide had any significant effects on available soil P. There was a significant increase in available soil P concentration in the surface 3 cm layer of soils on sites that had been partially cleared and grazed for 3 years by cattle supplemented with poultry litter. Only near centers of cattle activity was there a significant increase of P in the 3–15 cm layer, and only there was the enrichment sufficient to remove phosphorus limitation to herbage growth.