Do aeolian deposits and sand encroachment intensity shape patterns of vegetation diversity and plant functional traits in desert pavements?

The effects of sand encroachment on composition,diversity,and functional patterns of vegetation in drylands are rarely studied,and yet addressing these aspects is important to deepen our understanding of the biodiversity conservation.This study aimed to investigate the effect of sand encroachment on plant functional biodiversity of desert pavements(gravel deserts)in the Sahara Desert of Algeria.Plants were sampled and analyzed in three desert pavements with different levels of sand encroachment(LSE)and quantity of aeolian deposits(low,LLSE;medium,MLSE;and high,HLSE).Within the sample-plot area(100 m^(2)),density of every plant species was identified and total vegetation cover was determined.Plant taxonomic and functional diversity were analyzed and compared between LSE.Result showed that 19 plant species in desert pavements were classified into 18 genera and 13 families.Asteraceae and Poaceae were the most important families.The species Anabasis articulata(Forssk)Moq.characterized LLSE desert pavements with 11 species,whereas Thymelaea microphylla Coss.&Durieu ex Meisn.and Calobota saharae(C&D)Boatwr.&van Wyk were dominant species of desert pavements with MLSE(14 species)and HLSE(10 species),respectively.The highest values of species richness and biodiversity were recorded in desert pavements with MLSE,while low values of these ecological parameters were obtained in desert pavements with HLSE.Desert pavements with LLSE were characterized with the highest values of species abundances.Plant communities were dominated by chamaephytes,anemochorous,arido-active,and competitive stress-tolerant plants.The increase in LSE along the gradient from LLSE to HLSE induced significant changes in plant community variables including decreases in plant density,plant rarity,lifeform composition,morphological type,and aridity adaptation.Desert pavements with HLSE favor the degradation of vegetation and trigger biodiversity erosion.

Modeling and Mapping Sand Encroachment Risk as an Aid for Urban Planning in the United Arab Emirates (UAE)

Sand encroachment into urban areas represents a high risk factor for transportation infrastructural and urban development in the United Arab Emirates. The UAE is located in one of the world’s largest arid regions with a strong prevalence of sand movement and encroachment into urban areas, particularly in the last few years. The objective of this research is to develop a land surface process platform that models sand movements and further generates an encroachment risk index map of potential encroachment risk areas season-wise in the UAE. To achieve this objective, this research used elevation and land cover maps generated from Lands at 8 Operational Land Imager (OLI) data which represent the topography of the study area coupled with meteorological information on wind speed, temperature and precipitation. Furthermore, the study considered the vegetation cover as a major contribution factor to reduce sand encroachment. Using developed sand movement model for this research, sand encroachment risk maps were generated to help urban planners in cities making informed decisions of future urban protection structures and transportation networks that mitigate the effects of sand dunes encroachments in the UAE. A major finding of this research results conclude that during the summer season encroachment risk reaches 30% higher compared to the winter season due to the extremely high temperature which leads to reduced vegetation in the country. Urban planning decision maker may consider the finding of this research for future infrastructural adjustments.

Encroachment of the Buriganga River in Bangladesh

A survey on different aspects of Buriganga River encroachment was conducted in a 300 meter long encroached part of the river located in Dhaka, Bangladesh. A total of 100 respondents were surveyed and three Focus Group Discussions (FGDs) were arranged prior to the semi-structured questionnaire survey. It was observed that almost all of the respondents migrated to the study area. The majority of the respondents had better business opportunity (69.23%) as the cause of encroachment. Significant portions of the respondents occupying the encroached area were found to be landless (36.84%), small businessmen (31.58%) and people with political affluence (26.32%). Major portions (23.33%) of the encroached land were used for industrial development as well as housing and developmental projects. Negative health impact (40%) was found to be the main adverse effect of encroachment of the river. Other adverse effects included economic loss through obliteration of fisheries (35.71%), scarcity of clean water (32.14%), reduction of aesthetic value of the surroundings (25%) etc. For the protection of the river, the majority of the respondents opted for relocation of the industries (46.15%) and enforcement of strict rules and regulations (38.46%).

The Impact of Encroachment on the Distribution of Tree Species in Cross River National Park, Oban Division, Nigeria

Increasing human activities around protected area pinpoint to looming degradation and alteration of the component of such areas, especially where adequate measures are not taken to forestall encroachment. The Oban division of the Cross River National Park is one of the oldest rainforests and has been identified as a biodiversity hotspot. However, communities settling around the park have been involved in some economic activities for their livelihood. Resource utilization at the edge of the park may alter the components of the park such as species diversity. Therefore this study is geared towards assessing the impact of human encroachment and the concomitant impact on the distribution of species within the park. The study adopted participatory research methods which included Focus Group Discussion and participatory mapping as well as a plot based survey which involved the laying of sample plots within two zones of the park designated as areas bounded by cultivated land and areas bounded by fallow. Three 40 m × 40 m square plots are laid along a 320 meter transect measured from the boundary of the park at each buffer zone. The plots are separated by 100 m gap. From the result obtained, it is discovered that Musanga cercropoides dominates the outer plots of the cultivated zones and fallow zones comprising 20.2 and 21.5 percent respectively while Terminalia ivorensis dominates the middle and inner areas of the park. Moreover the composition of species decreases inward to the inner part of the park. Diversity index decreases in the order of 2.566 < 2.348 < 2.163 at the cultivated zones and 2.443 < 2.376 < 2.366 at the fallow zones. It is concluded that human activities close to the park alters the species composition of the park. Hence, it’s recommended that adequate alternatives livelihood and incentive be provided to support zone communities to reduce their dependents on the edge of the park.

Mechanisms,monitoring and modeling of shrub encroachment into grassland:a review

Shrub encroachment into arid and semi-arid grasslands has elicited extensive research attention worldwide under the background of climate change and increasing anthropogenic activities.Shrub encroachment may considerably impact local ecosystems and economies,including the conversion of the structure and function of ecosystems,the shift in ambient conditions,and the weakness of local stock farming capacity.This article reviews recent research progresses on the shrub encroachment process and mechanism,shrub identification and dynamic monitoring using remote sensing,and modeling and simulation of the shrub encroachment process and dynamics.These studies can help to evaluate the ecological effect of shrub encroachment,and thus,practically manage and recover the ecological environment of degraded areas.However,the lack of effective measures and data for monitoring shrub encroachment at a large spatial scale severely limits research on the mechanism,modeling,and simulation of shrub encroachment,and the shrub encroachment stages can hardly be quantitatively defined,resulting in insufficient analysis and simulation of shrub encroachment for different spatiotemporal scales and stages shift.Improvement in remote sensingbased shrub encroachment dynamic monitoring might be crucial for analyzing and understanding the process and mechanism of shrub encroachment,and multi-disciplinary and multi-partnerships are required in the shrub encroachment studies.

The effects of medical insurance and patients’ preference on manufacturer encroachment in a pharmaceutical supply chain

With the development of e-commerce,manufacturers have opportunities to sell products to consumers through direct channels in addition to independent retailers.Although manufacturers’encroachment upon the retailing market of traditional goods has been extensively studied,there is a lack of research on manufacturers’encroachment in a pharmaceutical supply chain.This paper analyzes a pharmaceutical manufacturer encroachment strategy by taking into account the distinctive features of drugs,in which drug expenses are covered by medical insurance only in the physical channel and patients'channel preference is also considered.We find that under certain circumstances,the manufacturer encroachment may lead to a win-win outcome for both the manufacturer and the retailer,contradicting the conventional wisdom that the manufacturer's encroachment into retail space is detrimental to the independent retailer.Additionally,the manufacturer is more likely to encroach when the incurred extra cost is sufficiently small,the perceived quality of the drug selling through the direct channel is sufficiently high and the out-of-pocket percentage cost of the drug selling in the physical channel is high.We further study the impact of manufacturer encroachment on social welfare and find that the introduction of encroachment decreases the social welfare when patients'perceived quality of the drug obtained through the online store is low and improves the social welfare when the perceived quality exceeds a certain threshold.

In-house or Outsourcing R&D?Manufacturer Technology Strategy in the Presence of Market Follower Encroachment

Facing the threat of market follower encroachment,this paper constructs game theoretical models based on different channel structures and market structures,investigates following manufacturer's encroachment strategy and technology strategies,and discusses the impact of following manufacturer's strategy on quality decisions.The results show that encroachment always improves consumer surplus by slashing prices when leading manufacturer adopts in-house R&D(IRD);otherwise,it results in lower consumer surplus with mild competition if leading manufacturer is at a technological disadvantage.Furthermore,the technology strategies of following manufacturer are related to their R&D capabilities.The superior one is outsourcing R&D(ORD)for the manufacturers when their R&D capability is weak,otherwise,IRD is optimal.In a word,the leading manufacturer always prefers IRD under certain conditions,while the following manufacturer always prefers ORD.In addition,encroachment restrains quality innovative motivation under fixed or quality-sensitive R&D costs,but can improve quality level when consumers have a higher reference dependency for quality;meanwhile,the following manufacturer adopting ORD is always beneficial to quality improvement.

Plant physiological changes along an encroachment gradient: an assessment of US Mid-Atlantic serpentine barrens

Aims Serpentine barrens of the Mid-Atlantic United States are globally rare,grass-dominated ecosystems thought to exclude C3 spe-cies and characterized by unique soil composition.However,like many grassland ecosystems globally,these sites are presently facing encroachment by surrounding forest.In this ecosystem,the tendril climbing vine,Smilax rotundifolia,forms dense thickets around bar-rens that typically precede forest encroachment.While numerous factors speculatively initiate and promote encroachment in these systems,few studies have examined photosynthetic responses of serpentine grasses to changes in resource availability initiated by encroachers or physiological ability of encroaching S.rotundifolia to colonize high-light barren environments.We sought to under-stand both environmental and physiological dynamics of encroach-ment along an irradiance gradient in these systems.Methods At three serpentine barren sites in southeastern Pennsylvania,physiological responses of the native grasses Sorghastrum nutans and Schizachyrium scoparium to increased shading by S.rotundi-folia were examined.Additionally,the physiological performance of S.rotundifolia in the forest understory was compared to that in sunlit barrens environments.Light-saturated photosynthesis(A_(sat)),stomatal conductance(g_(s)),instantaneous transpiration efficiency(ITE),maximum efficiency of photosystem II(F_(v)/F_(m)),midday leaf water potential(ψ_(leaf))and specific leaf area(SLA)were measured for all species over the course of the 2014 growing season.Two-way analyses of variance were used to assess changes in these param-eters across growing environments,as well as seasonally for each species.Multiple regression analyses were also performed to inves-tigate the influence of vapor pressure deficit(D)and leaf tempera-ture(T_(leaf))on A_(sat) and ITE.Important Findings Light-saturated photosynthesis was significantly greater in S.rotun-difolia growing in sun than in the shade(P<0.001)and early in the season(P=0.012).Sun S.rotundifolia had up to 27%greater A_(sat) than shaded plants.Even with reducedψleaf in the barrens,S.rotundifolia maintained high g_(s) though A_(sat) was limited by high D later in the growing season.These data are in agreement with recent research suggesting that plants are not subject to water limi-tation in Mid-Atlantic barrens.Unexpectedly,shaded grasses at the encroachment interface did not exhibit any significant reduc-tion in A_(sat).Declines in grass photosynthesis do not likely occur until S.rotundifolia rhizomes transition into monotypic thickets,completely excluding grasses.Encroachment by S.rotundifolia appears to be primarily facilitated by its ability to capitalize on light resources early on in the summer growing season,when environ-mental conditions are less stressful.

VTOL UAVs for Forest Monitoring and Management via Remote Sensing: A Case Study in Khao Yai National Park, Thailand

The utilization of UAVs (Unmanned Aerial Vehicles) has experienced a remarkable upsurge in various industries, including forestry. Their capacity to expeditiously and effectively cover large tracts of land has resulted in their widespread adoption as a valuable forest management and monitoring tool. The versatility of UAVs extends to their capability to perform quick and efficient surveys of large areas, inventory of tree species, and monitoring of forest health. This research paper reports on the successful utilization of VTOL (Vertical Takeoff and Landing) UAV that was designed and built at the IESSD (Institute of Earth Science and Sustainable Development) located in the AAA (Asia Aviation Academy) at KMITL (King Mongkut’s Institute of Technology Ladkrabang) Prince of Chumphon Campus, Thailand. The VTOL UAV is employed for resource and environmental missions, as well as forest monitoring by using remote sensing technology. VTOL UAVs are used for aerial surveillance to conduct air photography, data collection, and processing for resource and environmental missions. This research paper presents a comprehensive analysis of the areas at risk of deforestation and forest encroachment in a particular region of Khao Yai National Park in Thailand, highlighting the potential for the resulting photographs to inform evidence-based decision-making and facilitate sustainable forest management practices. This study offers recommendations to develop VTOL UAVs remote sensing capabilities and mitigate deforestation and forest encroachment in Khao Yai National Park.

Consumer Choice, Firm Performance and Channel Coordination in a Dual-Channel Distribution System

The expanding role of the Internet in consumer purchasing activities has created substantial new opportunities accessing to end-consumers. More and more manufacturers are beginning to sell products to potential consumers directly online while continuing to sell through the traditional brick-and-mortar retailers, a phenomenon leading to intense channel competition and conflicts. Using game theory, this research examines the effect of market segments, consumer choice and the acceptance of direct online channels on firm performance and the whole system’s profit. The analysis indicates that the addition of direct online channel does not necessarily harm the incumbent retailers. A win-win zone is proposed, in which both the manufacturer and the retailer benefit from the encroachment.

Influence of Tree Density on Vegetation Composition and Soil Chemical Properties in Savanna Rangeland of Eastern Cape, South Africa

The proliferation of woody species alters the vegetation structure, leading to loss of rangeland productivity. It aimed to assess the influence of tree density on vegetation and soil chemical properties at three levels of encroachment;open, moderate and dense. Each level of encroachment was replicated 3 times, a 5000 m2 plot was marked per replicate. Four belt transects 200 m2 were placed per plot. Woody species within each belt transect per replicate were identified and recorded to evaluate woody species composition. Grass species composition was assessed using a step point method. Soil was sampled per replicate and analysed for chemical properties. Results showed that 71% of grasses were increasers and 29% decreasers. Digitaria eriantha and Eragrostis obtusa were the most dominant species. Vachellia karoo and Aloe ferox were the most dominant woody species. The dense had high nitrogen (1.48%) compared to the moderate (0.23%) and the open (0.17%). Increaser species, soil carbon, soil pH increased with the increase of tree density. It was concluded that the replacement of highly palatable grasses with inferior ones was due to improper rangeland management practices. It was recommended that land users form rangeland management associations and set up conservation agreements for proper management of resources.

Impact of Controlling Shareholder Equity Pledge on Corporate Value

As an innovative financing behavior,equity pledge breaks the limit of traditional financing,and broadens the financing channels of companies and major shareholders.This paper comprehensively considers the impact of controlling shareholder equity pledge on corporate value from three research perspectives.The main conclusions are as follows:(1)When the equity pledge is not considered,the cash flow rights and voting rights of the company owned by the controlling shareholder are positively correlated with corporate value.That is,this presents incentive effect,but the existence of the separation of the two powers brings the second type of agency problem and reduces corporate value.(2)When considering the equity pledge,the controlling shareholder’s equity pledge may weaken the incentive effect and strengthen the encroachment effect which causing a reduction of corporate value.(3)Based on the accounting point of view,the controlling shareholder’s equity pledge is negatively correlated with the corporate performance,while the concentration of ownership dilutes this negative effect.(4)The balance of equity weakens the negative effect of the controlling shareholder’s equity pledge on corporate value,thereby reduces the negative impact of the equity pledge.

Micropolitics of Urban Slums:Variations in How the Urban Poor Organize Politically

What social factors influence political participation among the urban poor in Latin America?This paper engages conventional theories of political action pertaining to the urban poor characterized by analytical cleavages that have traditionally accounted for the majority of variation in political behavior.Using primary survey data from La Carpio slum of San José,Costa Rica,multivariate regression analyses show that differing social factors influence political participation in dissimilar ways.Because La Carpio slum respondents moderately participate in community‐based organizations and civil protest,nor are they manipulated by clientism,a theory of“quiet encroachment”may serve as an alternative framework for understanding the political behavior of respondents who seek to ameliorate harsh urban realities which have not improved in spite of a move to the center‐left by transitional political movements in Latin America.

Spatial and Temporal Habitat Use by GPS Collared Male Cheetahs in Modified Bushland Habitat

Cheetahs and other apex predators are threatened by human-wildlife conflict and habitat degradation. Bush encroachment creates one of the biggest forms of habitat change, thus it is important to understand the impact this has on habitat use. We investigated habitat preferences of five male cheetahs in Namibian farmlands degraded by bush encroachment. Cheetahs were tracked using satellite based Global System for Mobile (GSM) collars providing a higher resolution on ranging behavior. We aimed to investigate: 1) habitat characteristics;2) evidence for habitat selection;3) temporal activity partitioning;and 4) whether revisits to locations were related to habitat type. There were differences in habitat characteristics, showing that cheetahs were able to utilise different habitats. Fecal pellet counts revealed that warthog, oryx, scrub hare and kudu were most abundant. The cheetahs spent more time in high visibility shrubland, suggesting they selected rewarding patches within predominantly bush-encroached landscapes. The usage in marginal habitat was strikingly influenced by habitat type, with both previously cleared and open vegetated areas showing high proportions in edge use. Individuals exhibited significant temporal activity partitioning, showing peaks between late afternoon and early morning hours. This finding could be key to managing human-wildlife conflict by showing that increased protection such as the use of herders and livestock guarding dogs should be used as mitigation methods to minimize the impact of cheetah specific temporal patterns at all times as defined in this research. Visits to the same locations were not correlated to habitat type;revisits may be dictated by other reasons such as social interaction, prey density or avoidance of other predators. Findings from this study will help build existing knowledge on the effects bush encroachment has on cheetah habitat preference.

Gas Exchange Rates of Texas Persimmon (Diospyros texana) in Central Texas Woodlands

Diospyros texana (Texas persimmon) is a secondary species in most Juniperus ashei/Quercus fusiformis woodlands in central Texas. It has high density, but plants are mostly in the community understory. Light response curves at ambient and elevated levels of CO2 and temperature were measured for D. texana. The Anet (photosynthetic rate) increased significantly as both light level and CO2 levels increased but not temperature. The Amax (maximum photosynthetic rate) of D. texana in full sun at elevated levels of CO2 was increased for all treatments. Stomatal conductance increased with levels of CO2 but only if the interaction was removed from the model. Intercellular levels of CO2 increased with both temperature and CO2 treatments as did water use efficiency (WUE). Furthermore, light saturation (Lsat) increased with CO2 treatments and light compensation (Lcp) increased with temperature. The dark respiration (Rd) increased with both temperature and CO2 treatments. Markov population models suggested D. texana populations would remain ecologically similar in the future. However, sub-canopy light levels and herbivory should be considered when examining population projections. For example, Juniperus ashei juveniles are not recruited into any canopy unless there are high light levels. Herbivory reduces the success of Quercus juveniles from reaching the canopy. These factors do not seem to be a problem for D. texana juveniles which would allow them to reach the canopy without need of a high light gap and are not prevented by herbivory. Thus, Juniperus/Quercus woodlands will change in the future to woodlands with D. texana a more common species.

Conversion of savanna rangelands to bush dominated landscape in Borana,Southern Ethiopia

Introduction:Analyzing trends of land use systems and the changes occurred overtime is an effective way of assessing the impacts of land use/land cover(LULC)changes on ecosystem function.It provides important insights for understanding the spatial patterns of land use processes.The rangelands of southern Ethiopia are adversely affected by increased human population pressure,encroachment of crop cultivation,and bush encroachment.Hence,it is vital to understand the trends of rangeland vegetation cover dynamics.Methods:This paper evaluates land use/land cover changes and spatial patterns between 1987 and 2003 in Yabelo(5426 km2),Borena rangelands of southern Ethiopia.We used a combination of three Landsat Thematic Mapper(TM)1987,Landsat TM 1995 and Enhanced Thematic Mapper Plus(ETM+)2003,and local perceptions.A pixelbased supervised classification with maximum likelihood classifier was used to classify images.The accuracy of classification was assessed for 1987(81.8%),1995(84.6%),and 2003(81.3%).Results:The results showed that the Borana rangelands had undergone substantial changes during the last 16 years.Between 1987 and 2003,we observed a considerable increase in woodland cover(11.7%),bushland cover(17%),cultivated land(72.5%),and settlements(79.8%).The results showed a rapid decline in grassland cover(7.7%),shrubby grassland cover(86%),and bareland(0.7%).The spatial pattern analysis indicate that the Borana rangeland was fragmented and characterized by the proliferation of large numbers of patches with a decline in patch index,increased patch density,and irregular shape of patches within a landscape.Local communities’perceptions indicate that recurrent drought,increased human population size,and expansion of cultivation were largely responsible for the observed LULC changes in the study area.Conclusions:LULC changes contribute to rangeland degradation and weaken the traditional practices of rangeland management.We suggest appropriate management measures to halt the impact of disturbances on LULC dynamics and its implication on the livelihoods of the Borana pastoralists.

Linkages between woody plant proliferation dynamics and plant physiological traits in southwestern North America

Aims Woody plant encroachments in arid and semiarid ecosystems are widely reported but the physiological mechanisms still need to be further revealed.In the current study,we aim to determine whether differences in leaf physiological traits help explain grassland susceptibility to woody plant encroachment and whether distinctive physiological adaptations allow some shrub species to invade grasslands.Methods We compared physiological traits(photosynthesis,leaf water status,pigment compositions and leaf antioxidant capacities)of six species representing three functional groups:woody encroachers(Prosopis velutina,Larrea tridentata),woody non-encroachers(Acacia greggii,Lycium fremontii)and C4 grasses(Bouteloua curtipendula,Bouteloua barbata)which are naturally growing in a botanical garden in University of Arizona,USA.Important Findings We infer that P.velutina(encroacher)but not A.greggii or L.fremontii(non-encroachers)is encroaching in grasslands because the former species has higher water and light utilization efficiencies(instantaneous water use efficiency,instantaneous light use efficiency,and Fv/Fm).The extremely high carotenoid and total antioxidant capacity in its leaves appears to help the shrub L.tridentata(encroacher)survive high ambient oxidative damage caused by both drought and high light stresses in this grassland.The two C4 grass species,B.curtipendula and B.barbata,grow well in the arid ecosystem but may be susceptible to disturbances.

Variations in soil properties and native woody plant species abundance under Prosopis juliflora invasion in Afar grazing lands, Ethiopia

Introduction:Pastoralism and agro-pastoralism are the major modes of life in arid and semi-arid rangelands.However,rangeland quality and quantity are rapidly deteriorating due to a number of natural and human-induced factors,one of which is bush encroachment.Little is known on how bush encroachment affects the ecosystem functions and services expressed in terms of the native vegetation composition and structure,status of the soil seed bank,soil chemical and physical properties,and the abundance of mycorrhiza spores.Methods:We assessed woody species in 64 plots distributed across four levels of Prosopis juliflora invasion(high,medium,low,and none)at two sites,Amibara and Gewane,in the Afar Region,Ethiopia.We collected composite soil samples to investigate the soil seed bank,mycorrhizal associations,and spore abundance.Results:Plant biodiversity was generally low,with eight and four woody species in Gewane and Amibara,respectively.Prosopis juliflora was dominant in highly,moderately,and lowly invaded areas while Acacia senegal dominated the non-invaded areas.The average number of P.juliflora individuals ranged from 3/ha at non-invaded areas in Gewane to 4200/ha at highly invaded areas in Amibara while the total individual number of native woody species ranged from 0 to 88/ha at highly and lowly invaded areas,respectively.The population structure of trees/shrubs in all invasion areas showed an inverted J-shaped distribution,characterized by a high abundance of small individuals.Prosopis juliflora invasion was associated with high soil OC,Na,Ca,P,bulk density,and moisture content.Herbaceous seed numbers and species richness were highest in the moderately and highly invaded areas.All sampled tree species were associated with mycorrhiza but the percentage of root length colonization by different arbuscular mycorrhizal fungus structures varied significantly(p<0.05)across invasion categories and sites.Conclusions:Our results revealed that although P.juliflora invasion negatively impacted the availability of native woody livestock forage species,it had a positive effect on most soil physical and chemical properties.Such variable effects call out for sustainable management practices when invaded areas are restored.

Biodiversity change in heathland and its relationships with shifting local fire regimes and native species expansion

Aims Understanding the relationships among disturbance,invasion and species change is essential for effective management of many sys-tems.We investigated relationships among fire history,invasion by a native tree species,Allocasuarina huegeliana,and diversity change to understand the potential drivers of plant community alteration in a complex and biodiverse system.Methods We used plant species surveys from 1983 and 2011 to quantify spe-cies loss/gain and thence compositional changes.Additionally,we surveyed population densities of the invasive species and collated long-term fire history data for each site.General linear models and non-parametric models were used to assess the strength of relation-ships between the three variables of interest.Important Findings Within the last 30 years,~11%of the plant species richness was lost from the reserve.At an individual site level,we found only a 4%average decrease in overall plant species richness,but large species losses and gains that imply considerable compositional shifts.Though such shifts might be expected over 30 years,many of the gained species were common,potentially opportunistic species,while those lost were often locally rare woody perennials.In addi-tion,gained species tended to be expanding their recorded range westward suggesting that they may be responding to the regional drying climate.The relationship between invasion density and spe-cies loss was strong over all spatial scales.We identified a poten-tial state change to dominance by the native invasive particularly as high densities prevented species gain at the site scale.In these extreme cases of high invasive density and high biodiversity loss,we argue that there may be a need to directly address the expanding native population.