Revegetation Activities Research Articles

Kajian Implementasi Kegiatan Tanggung Jawab Sosial Perusahaan Pertambangan (Corporate Social Responsibility) Terhadap Pemberdayaan Masyarakat dan Lingkungan

The basic principles of CSR (Corporate Social Responsibility) in line with the concept of mining management is good and right (good mining practices). Minerals including coal should be optimally utilized because it must be able to protect the functions of the environment and society. Referring to this, company should be able to provide increased prosperity to its stakeholders. That includes community involvement in mining activities that pay attention to the better direction of environmental quality. This study aimed to examine the CSR program of PT. Bukit Asam ( Persero ) Tbk. The relation of community based bokashi with the empowerment of people and the environment after mining activities were studied. Bokashi fertilizer production is likely to increase the income of the people, also, on the other hand the company will be facilitated with the supply of fertilizer to be used in the reclamation stage, especially for re-vegetation activities. This research is a descriptive study using survey methods to groups of people who produce bokashi fertilizer. Based on F test results obtained all the independent variables together have a significant impact on the community empowerment variables with calculated F value of 7.293 > 2.766 compared F table . The result of partial test (t test) found that the variable of interest CSR ( X1 ) and the issue of CSR ( X2 ) affect positively towards community empowerment with the t value respectively 2.780 and 2.797 > than t table of 2.002 . In terms of the environment empowerment of post-mining activities, it could be seen from the results of monitoring activities. It showed that percentage of plants growth were 76.56 to 97.80%, the highest number of plants growth was 1,140 plants / ha and the lowest number was 685 plants / ha.

ESTIMATION OF BIOMASS AND CARBON CONTENT IN EX-COAL MINE LANDS

Potentially acid forming (PAF) and non-acid forming (NAF) lands are two types of lands found in ex-coal mine lands. These lands are similar to wetlands that have the potential to produce acid. PT. Jorong Barutama Greston is one of the coal mining companies required by the government to carry out reclamation by revegetation activities. Revegetation of ex-coal mine lands has generated plant biomass and carbon content to a specific value. The purposes of this study were to compare the amount of biomass and carbon content in ex-coal mine lands and to determine the best treatment for the ex-coal mine lands. The methods began with creating the measuring plots on the lands with different soil color (gray and brown). The soil color difference was determined by laboratory analysis test. For each different soil, the land revegetation was implemented with different treatments, 4 ameliorant treatments and 2 fertilization treatments so there were 8 units of treatments. Biomass and carbon content in each treatment unit were calculated by taking 4 plants as the laboratory test samples. The carbon content was calculated using the formula calculating the carbon of undergrowth with a diameter of < 5 cm. The results showed that the biomass and carbon content of plants in plot II were 17 times higher than those in plot I. The best treatment in plot I was the use of lime, bokashi and LOF (Liquid Organic Fertilizer) while the best treatment in plot II was the use of bokashi.

Disentangling relationships between plant diversity and decomposition processes under forest restoration

SummaryBiodiversity has been elucidated to be one of the major factors sustaining ecosystem functioning. The vast majority of studies showing a relationship between biodiversity and ecosystem functioning have come from experiments, and this knowledge has not yet been applied to most real‐world cases of conservation and management. This is especially true in forest ecosystems, characterized by the dominance of long‐lived organisms (trees) and high levels of structural complexity and environmental heterogeneity.To apply biodiversity–function relationships to actual forest management, there are several issues to be considered. These include employing a cross‐taxon perspective, as some functions (e.g. soil biogeochemical processes) cannot be maintained by a narrow set of organisms, as is usually the case with experimental systems. More specifically, although the interaction between above‐ and below‐ground diversity is important for many functions in forests, there are few studies that evaluated the roles of diversity in both subsystems in a manner that could be informative in practice.To evaluate the roles of above‐ and below‐ground diversity to support natural soil ecosystem functions, we conducted a decomposition experiment in the northern forests of Japan, which are currently under restoration management. The restoration area consists of mosaics of different vegetation types by various revegetation activities and establishment of ungulate exclosures. Using structural equation modelling and linear mixed‐effects models, we assessed direct and indirect pathways from diversity to functions by focusing on both of taxonomic and functional diversity indices. To put our findings into practice, we utilized a trait‐based approach, which provides a link between the functional consequences of human influences and ecosystem structure.We found little direct effects of tree diversity on below‐ground functions such as decomposition rate and litter stabilization. However, once the diversities of understorey herbaceous plants and soil fungi were considered as a possible mediating explanatory factor, we found a significant effect of tree diversity to indirectly support these functions by supporting these other types of biodiversity. Particularly, we found that the models based on functional trait diversity, rather than on taxonomic species richness, best explained the variation in below‐ground processes.Synthesis and applications. Forest restoration in the northern forests of Japan has had no explicit objective to restore soil functions. Nevertheless, afforestation, and the associated increase in tree diversity as a measure of forest restoration, was, although often unintentionally, proven effective for the maintenance of multiple ecosystem functions, such as soil biogeochemical processes. This finding suggests a great potential for management to make local tree assemblages functionally dissimilar and diverse for the sake of supporting and enhancing fundamental ecosystem functions in forests.

Plant diversity after sixteen years post coal mining in East Kalimantan, Indonesia

Komara LL, Choesin DN, Syamsudin TS. 2016. Plant diversity after sixteen years post coal mining in East Kalimantan,Indonesia. Biodiversitas 17: 531-538. Post coal mining areas need to be rehabilitated through reclamation and revegetation. The objective of this study was to evaluate plant diversity after 16 years of revegetation activities in a coal mining reclamation site in East Kalimantan. In an effort to restore plant diversity, the coal mining company began by planting fast growing species as pioneers, then planting local species after three years. This study compared a 20 hectare reclamation site with conditions in the pre-mining area, which covered 14,988 hectares. Vegetation sampling was conducted in 20 plots measuring 20x20 m2 along line transects, with 100 m distancebetween plots. A total of 104 plant species were found in the reclamation site, consisting of 76 tree species and 28 herbaceous species. Tree species consisted of 35 planted local species (e.g., Dryobalanops aromatica, Eusideroxylon zwageri, Macaranga gigantea), 25 planted non-local species, and 16 local species that grew spontaneously (e.g., Leucaena glauca, Lansium domesticum, Shorea laevis). In comparison, 133 species were found in the pre-mining site, consisting of 132 local tree species, one non-local tree species (Acacia mangium) and 52 herbaceous species. Tree species diversity index in the reclamation site after 16 years post mining (i.e., 3.54) was stilllower than in the pre-mining area (4.29); while the diversity indices for herbaceous plants were relatively similar (2.97 and 2.67 in the reclamation and pre-mining sites respectively). The slightly higher diversity of herbaceous plants in the reclamation site may be attributed to higher coverage per species in this site, despite lower species richness.

Resource use and greenhouse gas emissions from three wool production regions in Australia

Australia is the largest supplier of fine apparel wool in the world, produced from diverse sheep production systems. To date, broad scale analyses of the environmental credentials of Australian wool have not used detailed farm-scale data, resulting in a knowledge gap regarding the performance of this product. This study is the first multiple impact life cycle assessment (LCA) investigation of three wool types, produced in three geographically defined regions of Australia: the high rainfall zone located in New South Wales (NSW HRZ) producing super-fine Merino wool, the Western Australian wheat-sheep zone (WA WSZ) producing fine Merino wool, and the southern pastoral zone (SA SPZ) of central South Australia, producing medium Merino wool. Inventory data were collected from both case study farms and regional datasets. Life cycle inventory and impact assessment methods were applied to determine resource use (energy and water use, and land occupation) and GHG emissions, including emissions and removal associated with land use (LU) and direct land use change (dLUC). Land occupation was divided into use of arable and non-arable land resources. A comparison of biophysical allocation and system expansion methods for handling co-production of greasy wool and live weight (for meat) was included.Based on the regional analysis results, GHG emissions (excluding LU and dLUC) were 20.1 ± 3.1 (WA WSZ, mean ± 2 S.D) to 21.3 ± 3.4 kg CO2-e/kg wool in the NSW HRZ, with no significant difference between regions or wool type. Accounting for LU and dLUC emissions and removals resulted in either very modest increases in emissions (0.3%) or reduced net emissions by 0–11% depending on pasture management and revegetation activities, though a higher degree of uncertainty was observed in these results. Fossil fuel energy demand ranged from 12.5 ± 4.1 in the SA SPZ to 22.5 ± 6.2 MJ/kg wool (WA WSZ) in response to differences in grazing intensity. Fresh water consumption ranged from 204.3 ± 59.1 in the NSW HRZ to 393.7 ± 123.8 L/kg wool in the WA WSZ, with differences primarily relating to climate. Stress-weighted water use ranged from 11.0 ± 3.0 (SA SPZ) to 74.6 ± 119.5 L H2O-e/kg wool (NSW HRZ) and followed an opposite trend to water consumption in response to the different levels of water stress across the regions. Non-arable grazing land was found to range from 55% to almost 100% of total land occupation. Different methods for handling co-production of greasy wool and live weight changed estimated total GHG emissions by a factor of three, highlighting the sensitivity to this methodological choice and the significance of meat production in the wool supply chain. The results presented improve the understanding of environmental impacts and resource use in these wool production regions as a basis for more detailed full supply chain analysis.

Risks of overharvesting seed from native tallgrass prairies

Seed supply often limits the size and scope of restoration projects that require active revegetation. To meet demand from more and larger tallgrass prairie restoration projects in the Great Plains, U.S.A., seed is wild‐harvested—collected from remnant habitats—using agricultural combine harvesters. We investigated the potential impacts of wild‐harvest by comparing prairie remnants of northwestern Minnesota that varied in their histories of harvest frequency but were otherwise similar. We asked: (1) Do wild‐harvested prairies differ in species composition from unharvested prairies? (2) If so, can life history traits be used to predict the response of prairie communities to wild‐harvest? We conducted a retrospective study of 17 prairies harvested for seed frequently (annually/biennially), infrequently (2–3 times), or not at all. We sampled vegetation at 45 points within each site, recording all species present within 0.25 m2 quadrats. To address the first question, we used non‐metric multidimensional scaling and Mantel tests, followed by analysis of variance contrasts to identify any species less likely to occur on frequently harvested sites (“harvest‐negative”). For the second question, we used logistic regression to test whether lifespan, clonality, and seed production predicted harvest‐negative species. Plant community composition in frequently harvested prairies differed from that of infrequently or unharvested prairies. Fourteen species, generally short‐lived and non‐clonal, were classified as harvest‐negative. Our results suggest that frequent wild‐harvest disrupts reproduction of species relying on seed, and that life history traits may provide a basis for predicting a species' response to wild‐harvest.

Estimasi Stok Karbon di Kawasan Penambangan Akibat Perubahan Luas Penutupan Lahan Terkait dengan REDD

Deforestation and forest degradation caused by mining has had very great impact to global climate change, because one of the functions of forest vegetation is very important is capture and storage CO2 emissions. Revegetation activities in the area of mining is done in order to restore the forest vegetation. Research to estimate absorbtion CO2 as a result of carbon stock by forest vegetation needs to be done . Remote sensing technology through radar imagery can be applied to estimate forest vegetation carbon stock more quickly and efficient. The research was conducted in the gold mining area of PT . JResources Bolaang Mongondow. Main objective of this research is to estimate changes in forest covered land due to mining activities, estimation amount of carbon stored in 2008 , 2009, and 2010 and the economic value that can be obtained from stored carbon, using the estimated price based REDD schemes. The methodologies for measurements of the variables used in the calculation variable of above ground biomass using allometric and ALOS PALSAR image analysis of 2008, 2009, and 2010 to estimate the carbon stock in forests. The results showed there were widespread changes in forest land cover due to mining activities, and based on image analysis of 2008 , 2009, and 2010 , the amount of carbon stock in the research area respectively are 32,695,253.57 ton C, ton C 50,146,772.71 and 79,420,248.55 ton C. The economic value of carbon stock in 2010 are Rp.7,538,299,190,029.09 with price estimates and assumptions based on REDD scheme BAU Carbon savings in 2008.

Intra-Floodplain Seed Dispersal Limitation and Wetland Community Restoration

The broadleaf marsh community in the post-restoration reaches of the Kissimmee River floodplain, Florida, US, has failed to achieve the expected dominance based on pre-disturbance conditions. We examined the hypothesis that seed dispersal is a limiting factor delaying the expansion of characteristic taxa of a dominant wetland plant community, broadleaf marsh, from remnant populations into a partially restored river floodplain. Hydrochory and anemochory seed traps were deployed in the Kissimmee River for two week periods during four sampling periods over the course of a year. Study plots were divided among an area influenced by backwater effects from a downstream water control structure and the substantially drier floodplain with more fragmented and degraded broadleaf marsh communities to the north. Seed trapping showed that seeds of characteristic broadleaf marsh taxa, e.g., bulltongue arrowhead ( Sagittaria lancifolia ), pickerelweed ( Pontederia cordata ), and common buttonbush ( Cephalanthus occidentalis ), were only rarely dispersed and in small volumes north of the confluence of Oak Creek. Seed limitation due to a partially restored physical environment may be one of the factors contributing to minimal recovery of wetland communities in the Kissimmee River floodplain. As with fragmented regional scale landscapes with substantial distances among patches and an inhospitable matrix ecosystem, our research indicates that seed limitation may also be an issue for wetland restoration at local scales in contiguous floodplain wetlands such as the Kissimmee River. Active revegetation practices may be necessary for accelerating expansion of plant communities in large-scale river/floodplain restoration projects where local seed sources are spatially and hydrologically constrained.

Achieving Cross‐Scale Collaboration for Large Scale Conservation Initiatives

AbstractLarge‐scale conservation requires the involvement of numerous stakeholders to plan for and implement a range of activities across multiple scales. Establishing and sustaining the effective collaborations necessary to achieve this is a key challenge. Utilizing data from a large‐scale conservation initiative in the south west of Australia we characterize the interactions between stakeholders as a social network. We employ a novel network theoretical approach to assess the different forms of collaboration, including cross‐scale collaboration. We find that the social network predisposes cross‐scale collaboration for invasive animal control, an action where coordination of activities is necessary. We find that for revegetation activities there is little evidence of collaboration across scales, but this could be fostered by a subset of stakeholders acting in a “scale‐bridging” role. Addressing this will likely improve the effectiveness of revegetation efforts and the outcomes of the broader conservation initiative.

Reptiles in restored agricultural landscapes: the value of linear strips, patches and habitat condition

AbstractHabitat restoration, including revegetation of linear strips and enlargement of remnant patches, may benefit native fauna in highly fragmented landscapes. Such restoration has occurred around the world, even though the relative importance of strips and patches of vegetation remains controversial. Using reptile communities from south‐eastern Australia, we assessed the conservation value of revegetation in strips and alongside remnant patches compared with remnant vegetation and cleared roadsides. We also examined the distance that reptiles occurred from remnant patches into linear vegetation. We found that reptile species richness and counts did not substantially differ between revegetated, remnant and cleared habitats, or between linear strip and patch treatments. This may indicate that species sensitive to land clearing have already been lost from the landscape. These results imply that if specialist species have already been lost, we may be unable to measure the effects of agriculture on biodiversity. Furthermore, revegetation with the expectation that fauna will recolonize may be unrealistic and translocations may be necessary. Unexpectedly, we recorded higher species richness and counts of rare reptile species in remnant linear strips as distance from remnant patches increased. Ground‐layer attributes were important for increasing reptile species richness and counts and in structuring reptile communities, explaining approximately three times as much variation as remnant shape or vegetation type (remnant, revegetated, cleared). Management agencies should protect and effectively manage remnant linear strips if rarer reptiles are to be retained, paying particular attention to ground‐layer attributes. The decision to include ground layers in future revegetation activities will be more important than the shape of restored areas.

Regrowth provides complementary habitat for woodland birds of conservation concern in a regenerating agricultural landscape

Farmland abandonment often leads to an increase in vegetation cover in formerly cleared landscapes. In regions where forests and woodlands were cleared for agriculture, regrowth could be an effective way to increase species diversity by re-constructing a variegated landscape. Our study investigated the conservation outcomes for birds across a regenerating agricultural landscape. We compared bird composition across a range of land use and gradient of vegetation cover from cleared pasture, through regrowth sites of varying structure, to remnant forests. Bird community composition differed significantly among vegetation classes, with regrowth providing habitat for a complementary group of high conservation value species, rather than simply providing extra habitat for species that were otherwise well represented in the region. Variations in bird community composition were best explained by site variables that contributed to vegetation structure and internal patch variation. Regrowth had a higher diversity of cover than forest or pasture, and this created habitat for many woodland bird species. Regrowth vegetation may be slower to proceed, but it has the potential to complement active revegetation activities in adjacent production areas and enhance connectivity between remnant forest patches. While the benefits of regrowth are context specific, where regrowth improves landscape heterogeneity, there is great potential for conservation gains for birds.

Modelling the benefits of habitat restoration in socio-ecological systems

Decisions affecting the management of natural resources in agricultural landscapes are influenced by both social and ecological factors. Models that integrate these factors are likely to better predict the outcomes of natural resource management decisions compared to those that do not take these factors into account. We demonstrate how Bayesian Networks can be used to integrate ecological and social data and expert opinion to model the cost-effectiveness of revegetation activities for restoring biodiversity in agricultural landscapes. We demonstrate our approach with a case-study in grassy woodlands of south-eastern Australia. In our case-study, cost-effectiveness is defined as the improvement in native reptile and beetle species richness achieved per dollar spent on a restoration action. Socio-ecological models predict that weed control, the planting of trees and shrubs, the addition of litter and timber, and the addition of rocks are likely to be the most cost-effective actions for improving reptile and beetle species richness. The cost-effectiveness of restoration actions is lower in remnant and revegetated areas than in cleared areas because of the higher marginal benefits arising from acting in degraded habitats. This result is contingent on having favourable landowner attitudes. Under the best-case landowner demographic scenarios the greatest biodiversity benefits are seen when cleared areas are restored. We find that current restoration investment practices may not be increasing faunal species richness in agricultural landscapes in the most cost-effective way, and that new restoration actions may be necessary. Integrated socio-ecological models support transparent and cost-effective conservation investment decisions. Application of these models highlights the importance of collecting both social and ecological data when attempting to understand and manage socio-ecological systems.

Evaluating the performance of a centralised government geodatabase in capturing publicly-funded natural resource management activities in Victoria, Australia

Over the past two decades the Australian government has invested billions of dollars into restoring and conserving Australia's environment and natural resources. However, audits of major programs have, in many cases, found it hard to verify where money was spent, let alone estimate what ecological impact it achieved. In Victoria, the Catchment Activity Management System (CAMS) – a centralised geodatabase intended to capture information about on-ground natural resource management (NRM) works – was developed around 2000 to enable uniform reporting at regional and state levels. The advent of this system was lauded for its potential to streamline reporting, but also to facilitate monitoring of the effectiveness of those projects. We evaluated the representation of native vegetation protection, revegetation and remnant restoration activities in CAMS by comparing these data to equivalent, independently generated data from three catchment management regions. The CAMS database captured just over half of the relevant works directly co-funded by government as spatial records. Since these accounted for approximately two-thirds of the total area of publicly co-funded works for that period, it follows that smaller sites were more likely to have been omitted from CAMS. Although the entry of works into CAMS only became encouraged in 2001, each CMA had undertaken some back-filling of the database and those sites that were included in CAMS were typically accurately mapped and located. Although our aim was not to recommend what information might be collected in CAMS to improve the ecological reporting, we believe our review will help inform that purpose. Given that many basic fields within the database remain unpopulated, consideration should be given to how those who collect the data could be encouraged to undertake diligent collection of more complex information that might be required to inform ecological change analyses.

Effectiveness of Calluna-heathland restoration methods after invasive plant control

Restoring natural communities after invasive plant control is one of the fundamental challenges of ecological restoration. Despite advances in invasive control methods, restoration failures caused by a lack of native community re-establishment are common. This is especially frequent in the upland heathlands of Great Britain invaded by Pteridium aquilinum. As a consequence, active revegetation methods are needed to increase the performance of native plant species. Here, we assessed the effectiveness of Calluna-heathland vegetation restoration treatments on the developing plant community composition in combination with a set of recommended Pteridium-control methods applied at the local scale. Four stand-alone replicated experiments were set up in two regions of Great Britain. The experiments had a similar randomized block split- or split–split-plot design with six Pteridium-control treatments applied randomly to the main-plots (10m×40m); and Calluna-heathland vegetation site-specific restoration treatments applied to sub- and sub-sub-plots. The restoration treatments included stock-poof fencing, fertilizing, harrowing, seeding and prescribed litter-burning. The results showed that the effectiveness of site-specific Calluna-heathland restoration methods applied in conjunction with Pteridium-control methods was very low. Only sheep grazing and prescribed Pteridium-litter burning favoured the restoration of Calluna-heathland community composition. In contrast, fencing, fertilizing and harrowing were ineffective. Surprisingly, Calluna seeding only showed short-term positive effects when applied with asulam spray treatments. Considering the costs and benefits of the restoration measures studied as part of this integrated Pteridium-control/heathland restoration programme, the most successful methods were sheep grazing and prescribed Pteridium-litter burning; both are traditional methods of heathland management. It seems that effective restoration actions should initiate gradual change that aims to create a continuous transition to a more desirable conservation value state.

Balancing trade-off issues in land use change and the impact on streamflow and salinity management

The south-west region of the Goulburn–Broken catchment in the south-eastern Murray–Darling Basin in Australia faces a range of natural resource challenges. A balanced strategy is required to achieve the contrasting objectives of remediation of land salinization and reducing salt export, while maintaining water supply security to satisfy human consumption and support ecosystems. This study linked the Catchment Analysis Tool (CAT), comprising a suite of farming system models, to the catchment-scale CATNode hydrological model to investigate the effects of land use change and climate variation on catchment streamflow and salt export. The modelling explored and contrasted the impacts of a series of different revegetation and climate scenarios. The results indicated that targeted revegetation to only satisfy biodiversity outcomes within a catchment is unlikely to have much greater impact on streamflow and salt load in comparison with simple random plantings. Additionally, the results also indicated that revegetation to achieve salt export reduction can effectively reduce salt export while having a disproportionately smaller affect on streamflows. Furthermore, streamflow declines can be minimized by targeting revegetation activities without significantly altering salt export. The study also found that climate change scenarios will have an equal if not more significant impact on these issues over the next 70 years. Uncertainty in CATNode streamflow predictions was investigated because of the effect of parameter uncertainty. Copyright © 2012 John Wiley & Sons, Ltd.

喀斯特峰丛洼地土壤剖面微生物特性对植被和坡位的响应

选取广西环江县喀斯特峰丛洼地:草丛(T)、灌丛(S)、原生林(PF)(中坡位)不同植被类型,原生林上、中、下不同坡位,按土壤发生层采集淋溶层(A 层,0-10 cm)、过渡层(AB层,20-30 cm,草丛和灌丛;30-50 cm,原生林)、淀积层 (B层,70-100 cm)样品,研究土壤微生物量碳、氮(Soil microbial biomass carbon (SMBC)、soil microbial biomass nitrogen (SMBN))、微生物碳熵、氮熵(ratio of SMBC to soil organic carbon (<em>q</em>MBC)、ratio of SMBN to soil total nitrogen (<em>q</em>MBN))、土壤基础呼吸 (soil basic respiration (SBR))以及代谢熵 (microbial metabolic quotient (<em>q</em>CO₂))的剖面分异特征及其影响因素。结果表明,植被、土层深度显著影响土壤微生物量及基础呼吸,随植被恢复,SMBC、SMBN、SBR由草丛、灌丛、原生林依次上升,并随土壤发生层位的加深逐渐减少,<em>q</em>CO₂在3种植被类型间差异显著:T>PF>S;原生林A层SMBC, SMBN在各坡位间均显著高于AB层、B层, SBR在A层由下坡位至上坡位递减,而在AB和B层的上、下坡位间无显著差异,<em>q</em>CO₂坡位间无显著差异(<em>P</em>>0.05);SMBC与SMBN之间存在显著正相关(<em>r</em>=0.825,<em>P</em><0.01, <em>n</em>=45),且SMBC、SMBN、SBR分别与有机碳、全氮、碱解氮均呈显著正相关。因此,随植被恢复,土壤质量明显改善,且坡位对A层土壤的影响较AB层和B层更显著,对于维持土壤微生物调节的土壤养分循环功能,调控土壤氮素营养与土壤有机质同等重要,这为合理制订喀斯特生态恢复措施提供了理论依据。;Closed-forest type land coverage is an important measure for the restoration of degraded karst ecosystems, and soil microorganisms are one of the most useful indicators of soil quality; however, little is known about the effects of the vegetation pattern and slope on microbial characteristics within the soil profile. In this study, soil samples derived from three different genetic layers along the profile-leaching layer (A, 0-10 cm); transition layer (AB, 20-30 cm, tussock (T) and shrub (S); 30-50 cm, primary forest (PF)); and deposited layer (B, 70-100 cm)-were collected from the middle slope position of three ecosystems-tussock (T), shrub (S), and primary forest (PF)and in addition, from the upper and lower slope positions of primary forest (PF). The study determined soil microbial biomass carbon (SMBC), nitrogen (SMBN), ratio of SMBC to soil organic carbon (<em>q</em>MBC), ratio of SMBN to soil total nitrogen (<em>q</em>MBN), basic respiration (SBR), microbial metabolic quotient (<em>q</em>CO₂) and certain physico-chemical characteristics in order to identify changes in the microbial characteristics along the soil profile in response to the typical vegetation pattern and slope position, and the relationships between the soil microbial- and physico-chemical characteristics. Our results showed that the vegetation pattern and the type of soil genetic layer significantly affected soil microbial biomass and basic respiration, whereas no consistent effect on the slope position was observed. The values of soil microorganism biomass carbon along the soil profile from tussock (T) and shrub (S) ecosystems were 56.7-367 and 161-640 mg/kg, respectively, which were significantly lower than the 532-1217 mg/kg value for the primary forest (PF) ecosystem. The same trend (T<S<PF) was observed for soil microbial biomass nitrogen and soil basic respiration, but a different trend (T>PF>S) was observed for the microbial metabolic quotient. SMBC, SMBN, qMBC, and SBR declined for each progressive soil genetic layer, and the effect of slope position on these indicators was more significant within the leaching layer (A) than in the transition (AB) and deposited layers (B). In contrast, for SBR, two-way ANOVA showed that the slope position had no significant influence on <em>q</em>CO₂. A significant positive correlation was observed between SMBC and SMBN (<em>r</em>=0.825, <em>P </em>< 0.01, <em>n</em>=45). Further, there were significant differences in soil nutrients (TN, SOM, AN) along the profile between different vegetation patterns and slope positions; and SMBC, SMBN, and SBR were also correlated with organic carbon, total nitrogen, and available nitrogen. As a result, vegetation restoration had positive effects on the physico-chemical and microbial characteristics, and these changes were more prominent in surface soil than in deep soil. Soil nitrogen nutrition and soil organic matter were equally important for the maintenance of the soil microbial community and its ecological function. These findings should help facilitate preservation and revegetation activities in karst regions.

Floresta urbana: síndrome de dispersão e grupos ecológicos de espécies do sub-bosque

O estudo foi realizado em um fragmento de floresta urbana, localizado na cidade de Camaragibe, Pernambuco, Brasil tendo como objetivo a avaliação do potencial desse fragmento como fonte de propágulos para projetos de enriquecimento em áreas de mesma tipologia florestal. Para tanto, foi realizada a classificação dos grupos ecológicos e da síndrome de dispersão das espécies arbustivo-arbórea em regeneração natural. A biota foi representada por 40 espécies, pertencentes a 38 gêneros e 24 famílias botânicas o que totalizou 395 indivíduos. Destas, 38 foram identificadas em nível específico e 2 em nível genérico. As famílias que mais contribuíram para riqueza florística em termos de quantidade de espécies por ordem alfabética foram: Anacardiaceae, Annonaceae, Burseraceae, Caesalpiniaceae, Euphorbiaceae, Meliaceae, Mimosaceae, Moraceae, Rubiaceae, Sapindaceae e Tiliaceae. A síndrome de dispersão predominante foi a zoocórica, identificada em 87,5%, seguida pela anemocoria, que representou 7,5% dos casos. Os resultados gerais apontaram o bom estado de conservação desse fragmento e a viabilidade de sua utilização como fonte de propágulos para ações de revegetação em áreas de mesma tipologia florestal.

Arresting the rate of land clearing: Change in woody native vegetation cover in a changing agricultural landscape

Understanding the magnitude and drivers of background vegetation change at the landscape scale is an important step towards improving management strategies and policy. This study examined historical (1946–2008) and contemporary (2004–2008) change in extent of native trees in three case study areas in central Victoria, Australia using aerial photographs. To investigate the drivers and impacts of the documented change we used aerial photograph interpretation and workshops with landholders and natural resource management agency staff.By 1946 much of the clearing in each case study had already occurred leaving native tree cover at 5–38% across the three regions. From 1946 to 2008 there was a slight net decrease in tree cover in all three case study areas. Spontaneous regeneration and revegetation, mapped using 2004–2008 aerial photographs, accounted for 1.9 and 1.0% gain of the case study areas respectively. In each region the gain in extent of immature trees was greater than the net loss of mature trees, excluding remnant paddock trees. Across all case study areas socio-economic factors, including commodity prices, government legislation and natural resource management incentives were the predominant and persistent determinants of vegetation change.Attempts to increase the extent and quality of native vegetation in the landscape needs to consider: the impact of large-scale drivers of vegetation change; the biodiversity value of the regenerating vegetation compared to existing remnants and active revegetation.

An event-based approach to understanding the hydrological impacts of different land uses in semi-arid catchments

Summary In semi-arid catchments around the world re-vegetation is often implemented to reduce quick surface runoff, combat severe soil erosion, restore degraded ecosystem functionality, and, ultimately, improve ecosystem productivity. However, to date, in these water stressed regions, the event-based hydrological impact of different land uses induced by re-vegetation activities is not fully understood at the watershed scale. Traditional hillslope plot experiments and paired watershed experiments have proved difficult to up-scale to a watershed level. In 2006 and 2007, we used broad-crested weirs to measure event streamflow from six catchments within the Caijiachuan watershed (area = 40.1 km2), located in the Loess Plateau, a semi-arid region in China. The six catchments have different land use compositions with functional combinations of crop, grassland, shrubland, secondary forest, and plantations. Over the same period, event rainfall was measured by a network of rainfall gauges deployed over the study site. We examined the difference in hydrological properties between the catchments using the non-parametric Firedman test, and differentiated the role of each land use in governing watershed hydrology using a numerical analysis technique. Our results showed important differences between the six catchments with respect to event runoff coefficients, normalized peak flow, and event duration. Each land use played a different role in catchment hydrology, as shown by the different mean runoff coefficients (rc) and mean representative surface flow velocities (V). Compared to secondary forest (rc = 0.017 and V = 0.07 m s−1), plantations (rc = 0.001 and V = 0.18 m s−1) provide a greater potential for increasing shearing force and had a larger impact on runoff reduction. Although shrubland (rc = 0.096 and V = 0.20 m s−1) and grassland (rc = 0.127 and V = 0.02 m s−1) have similar magnitude of mean runoff coefficients, grassland seems more capable of trapping sediment due to its lower surface runoff velocity. Cropland (rc = 0.008 and V = 0.05 m s−1) exerted an important effect on runoff reduction and a moderate effect on flow retardation. We concluded that, to combat severe soil erosion while minimizing water use, re-vegetation in the semi-arid Loess Plateau should not overly, or even solely, rely on plantations. Alternatively, to produce the desired ecosystem functionality, preservation and establishment of grassland during re-vegetation processes should be encouraged, at least, in the early stage of ecological restoration within a “successional re-vegetation” framework.

Deer and Invasive Plant Species Suppress Forest Herbaceous Communities and Canopy Tree Regeneration

The loss of native biodiversity is a major ecological issue in human-dominated landscapes. In particular, the tree regeneration failure of deciduous forests remnants in suburban landscapes is of great concern to land managers and forestry associations. We tested the responses over two growing seasons of herbaceous plants and tree seedling survival and growth to the removal of invasive plant competition and deer herbivory. We first tested the response of understory vegetation to the removal of Microstegium vimineum (Japanese stiltgrass), a non-native invasive grass, and the removal of deer herbivory, via exclosures, in two forest fragments in central New Jersey. We then explored the restoration potential of planted seedlings of canopy tree dominants, Acer rubrum, Fraxinus americana, and Quercus rubra. The herbaceous community responded with an increase in species richness to the removal of M. vimineum. There was no response of the herbaceous community to the removal of deer herbivory, indicating that the herbaceous community will not recover rapidly from removal of these stressors alone. Survival and height growth of naturally regenerating tree seedlings increased with the removal of M. vimineum and the removal of deer herbivory, but these effects were not interactive. The survival and growth of planted seedlings of two tree species, F. americana and Q. rubra, were depressed by the presence of M. vimineum. Our results suggest that intensive management of M. vimineum and deer populations as well as active re-vegetation of herbaceous communities and tree seedlings are necessary to restore plant biodiversity in suburban deciduous forests.