Predators on private land: broad-scale socioeconomic interactions influence large predator management

The proliferation of private land conservation areas (PLCAs) is placing increasing pressure on conservation authorities to effectively regulate their ecological management. Many PLCAs depend on tourism for income, and charismatic large mammal species are considered important for attracting international visitors. Broad-scale socioeconomic factors therefore have the potential to drive fine-scale ecological management, creating a systemic scale mismatch that can reduce long-term sustainability in cases where economic and conservation objectives are not perfectly aligned. We assessed the socioeconomic drivers and outcomes of large predator management on 71 PLCAs in South Africa. Owners of PLCAs that are stocking free-roaming large predators identified revenue generation as influencing most or all of their management decisions, and rated profit generation as a more important objective than did the owners of PLCAs that did not stock large predators. Ecotourism revenue increased with increasing lion (Panthera leo) density, which created a potential economic incentive for stocking lion at high densities. Despite this potential mismatch between economic and ecological objectives, lion densities were sustainable relative to available prey. Regional-scale policy guidelines for free-roaming lion management were ecologically sound. By contrast, policy guidelines underestimated the area required to sustain cheetah (Acinonyx jubatus), which occurred at unsustainable densities relative to available prey. Evidence of predator overstocking included predator diet supplementation and frequent reintroduction of game. We conclude that effective facilitation of conservation on private land requires consideration of the strong and not necessarily beneficial multiscale socioeconomic factors that influence private land management.

Sediment Budget for Cane Land on the Lower Herbert River Floodplain, North Queensland, Australia

Land use in the river catchments of tropical North Queensland appears to have increased the export of sediment and nutrients to the coast. Although evidence of harmful effect of sediment on coastal and riverine ecosystems is limited, there is a growing concern about its possible negative impacts. Sugarcane cultivation on the floodplains of the tropical North Queensland river catchments is thought to be an important source of excess sediment in the river drainage systems. Minimum-tillage, trash blanket harvesting has been shown to reduce erosion from sloping sugarcane fields, but in the strongly modified floodplain landscape other elements (e.g. drains, water furrows and headlands) could still be important sediment sources. The main objectives of this thesis are to quantify the amount of sediment coming from low-lying cane land and identify the important sediment sources in the landscape. The results of this thesis enable sugarcane farmers to take targeted measures for further reduction of the export of sediment and nutrients. Sediment budgets provide a useful approach to identify and quantify potential sediment sources. For this study a sediment budget is calculated for a part of the Ripple Creek catchment, which is a sub-catchment of the Lower Herbert River. The input of sediment from all potential sources in cane land and the storage of sediment within the catchment have been quantified and compared with the output of sediment from the catchment. Input from, and storage on headlands, main drains, minor drains and water furrows, was estimated from erosion pin and surface profile measurements. Input from forested upland, input from fields and the output at the outlet of the catchment was estimated with discharge data from gauged streams and flumes. Data for the sediment budget were collected during two ‘wet’-seasons: 1999-2000 and 2000-2001. The results of the sediment budget indicate that this tropical floodplain area is a net source of sediment. Plant cane fields, which do not have a protective trash cover, were the largest net source of sediment during the 1999-2000 season. Sediment input from water furrows was higher, but there was also considerable storage of sediment in this landscape element. Headlands tend to act as sinks. The source or sink function of drains is less clear, but seems to depend on their shape and vegetation cover. An important problem in this study is the high uncertainty in the estimates of the sediment budget components and is, for example, likely to be the cause of the imbalance in the sediment budget. High uncertainties have particularly affected the results from the 20002001 season. The main source of uncertainty is spatial variation in the erosion and deposition processes. Uncertainty has to be taken into consideration when interpreting the budget results. The observation of a floodplain as sediment source contradicts the general understanding that floodplains are areas of sediment storage within river catchments. A second objective of this thesis was therefore to provide an answer to the question: how can floodplains in the tropical North Queensland catchments can be a source of sediment? In geomorphic literature various factors have been pointed out, that could control floodplain erosion processes. However, their importance is not 'uniquely identified'. Among the most apparent factors are the stream power of the floodwater and the resistance of the floodplain surface both through its sedimentary composition and the vegetation cover. If the cultivated floodplains of the North Queensland catchments are considered in the light of these factors, there is a justified reason to expect them to be a sediment source. Cultivation has lowered the resistance of their surface; increased drainage has increased the drainage velocity and flood control structures have altered flooding patterns. For the Ripple Creek floodplain four qualitative scenarios have been developed that describe erosion and deposition under different flow conditions. Two of these scenarios were experienced during the budget study, involving runoff from local hillslopes and heavy rainfall, which caused floodplain erosion. In the longer term larger flood events, involving floodwater from the Herbert River, may lead to different erosion and deposition processes. The present study has shown that the tropical floodplain of the Herbert River catchment can be a source of sediment under particular flow conditions. It has also shown which elements in the sugarcane landscape are the most important sediment sources under these conditions. This understanding will enable sugarcane farmers to further reduce sediment export from cane land and prevent the negative impact this may have on the North Queensland coastal ecosystems.

Euphorbia tirucalli L.–Comprehensive Characterization of a Drought Tolerant Plant with a Potential as Biofuel Source

Of late, decrease in mineral oil supplies has stimulated research on use of biomass as an alternative energy source. Climate change has brought problems such as increased drought and erratic rains. This, together with a rise in land degeneration problems with concomitant loss in soil fertility has inspired the scientific world to look for alternative bio-energy species. Euphorbia tirucalli L., a tree with C3/CAM metabolism in leaves/stem, can be cultivated on marginal, arid land and could be a good alternative source of biofuel. We analyzed a broad variety of E. tirucalli plants collected from different countries for their genetic diversity using AFLP. Physiological responses to induced drought stress were determined in a number of genotypes by monitoring growth parameters and influence on photosynthesis. For future breeding of economically interesting genotypes, rubber content and biogas production were quantified. Cluster analysis shows that the studied genotypes are divided into two groups, African and mostly non-African genotypes. Different genotypes respond significantly different to various levels of water. Malate measurement indicates that there is induction of CAM in leaves following drought stress. Rubber content varies strongly between genotypes. An investigation of the biogas production capacities of six E. tirucalli genotypes reveals biogas yields higher than from rapeseed but lower than maize silage.

Potential of incorporating ocean currents in fishing vessels

The fishing sector has been suffering a strong setback, with reduction in fishing stocks and more recently with the reduction of the fishing fleet. One of the most important factors for this decrease, is related to the continuous difficulty to find fish with quality and quantity, allowing the sector work constantly all year long. However other factors are affecting negatively the fishing sector, in particular the huge maintenance costs of the ships and the high diary costs that are necessary for daily work of each vessel. One of the main costs associated with daily work, is the fuel consumption. As an example, one boat with 30 meters working around 17 hours every day, consumes 2500 liters of fuel/day. This value is very high taking into account the productivity of the sector. Supporting this premise was developed a project with the aim of reducing fuel consumption in fishing vessels. The project calls “ShipTrack” and aims the use of forecasts of ocean currents in the routes of the ships. The objective involves the use of ocean currents in favor, and avoiding ocean currents against, taking into account the course of the ship, in order to reduce fuel consumption and increase the ship speed. The methodology used underwent the creation of specific Software, in order to optimize routes, taking into account the forecasts of the ocean currents. These forecasts are performed using numerical modelling, methodology that become more and more important in all communities, because through the modeling, it can be analyzed, verified and predicted important phenomena to all the terrestrial ecosystem. The objective was the creation of Software, however its development was not completed, so it was necessary a new approach in order to verify the influence of the ocean currents in the navigation of the fishing ship "Cruz de Malta". In this new approach, and during the various ship routes it was gathering a constant information about the instant speed, instantaneous fuel consumption, the state of the ocean currents along the course of the ship, among other factors. After 4 sea travels and many routes analyzed, it was possible to verify the influence of the ocean currents in the Ship speed and in fuel consumption. For example, in many stages of the sea travels it was possible to verify an increase in speed in zones where the ocean currents are in favor to the ships movements. This incorporation of new data inside the fishing industry, was seen positively by his players, which encourages new developments in this industry.

Previous land use and climate influence differences in soil organic carbon following reforestation of agricultural land with mixed-species plantings

Reforestation of agricultural land with mixed-species environmental plantings (native trees and shrubs) can contribute to mitigation of climate change through sequestration of carbon. Although soil carbon sequestration following reforestation has been investigated at site- and regional-scales, there are few studies across regions where the impact of a broad range of site conditions and management practices can be assessed. We collated new and existing data on soil organic carbon (SOC, 0–30 cm depth, N = 117 sites) and litter (N = 106 sites) under mixed-species plantings and an agricultural pair or baseline across southern and eastern Australia. Sites covered a range of previous land uses, initial SOC stocks, climatic conditions and management types. Differences in total SOC stocks following reforestation were significant at 52% of sites, with a mean rate of increase of 0.57 ± 0.06 Mg C ha−1 y−1. Increases were largely in the particulate fraction, which increased significantly at 46% of sites compared with increases at 27% of sites for the humus fraction. Although relative increase was highest in the particulate fraction, the humus fraction was the largest proportion of total SOC and so absolute differences in both fractions were similar. Accumulation rates of carbon in litter were 0.39 ± 0.02 Mg C ha−1 y−1, increasing the total (soil + litter) annual rate of carbon sequestration by 68%. Previously-cropped sites accumulated more SOC than previously-grazed sites. The explained variance differed widely among empirical models of differences in SOC stocks following reforestation according to SOC fraction and depth for previously-grazed (R2 = 0.18–0.51) and previously-cropped (R2 = 0.14–0.60) sites. For previously-grazed sites, differences in SOC following reforestation were negatively related to total SOC in the pasture. By comparison, for previously-cropped sites, differences in SOC were positively related to mean annual rainfall. This improved broad-scale understanding of the magnitude and predictors of changes in stocks of soil and litter C following reforestation is valuable for the development of policy on carbon markets and the establishment of future mixed-species environmental plantings.

DISSOLVED AND GASEOUS FLUXES OF CARBON AND NITROGEN FROM URBAN WATERSHEDS OF THE CHESAPEAKE BAY

Carbon and nitrogen loading to streams and rivers contributes to eutrophication as well as greenhouse gas (GHG) production in streams, rivers and estuaries. My dissertation consists of three research chapters, which examine interactions and potential trade-offs between water quality and greenhouse gas production in urban streams of the Chesapeake Bay watershed. My first research project focused on drivers of carbon export and quality in an urbanized river. I found that watershed carbon sources (soils and leaves) contributed more than in-stream production to overall carbon export, but that periods of high in-stream productivity were important over seasonal and daily timescales. My second research chapter examined the influence of urban storm-water and sanitary infrastructure on dissolved and gaseous carbon and nitrogen concentrations in headwater streams. Gases (CO2, CH4, and N2O) were consistently super-saturated throughout the course of a year. N2O concentrations in streams draining septic systems were within the high range of previously published values. Total dissolved nitrogen concentration was positively correlated with CO2 and N2O and negatively correlated with CH4. My third research chapter examined a long-term (15-year) record of GHG emissions from soils in rural forests, urban forest, and urban lawns in Baltimore, MD. CO2, CH4, and N2O emissions showed positive correlations with temperature at each site. Lawns were a net source of CH4 + N2O, whereas forests were net sinks. Gross CO2 fluxes were also highest in lawns, in part due to elevated growing-season temperatures. While land cover influences GHG emissions from soils, the overall role of land cover on this flux is very small (< 0.5%) compared with gases released from anthropogenic sources, according to a recent GHG budget of the Baltimore metropolitan area, where this study took place.

Is land condition a useful indicator of soil organic carbon stock in Australia?

The grazing lands of northern Australia contain a substantial soil organic carbon (SOC) stock due to the large land area. Manipulating SOC stocks through grazing management has been presented as an option to offset national greenhouse gas emissions from agriculture and other industries. However, research into the response of SOC stocks to a range of management activities has variously shown positive, negative or negligible change. This uncertainty in predicting change in SOC stocks represents high project risk for government and industry in relation to SOC sequestration programs. In this paper, we seek to address the uncertainty in SOC stock prediction by assessing relationships between SOC stocks and grazing land condition indicators. We reviewed the literature to identify land condition indicators for analysis and tested relationships between identified land condition indicators and SOC stock using data from a paired-site sampling experiment (10 sites). We subsequently collated SOC stock datasets at two scales (quadrat and paddock) from across northern Australia (329 sites) to compare with the findings of the paired-site sampling experiment with the aim of identifying the land condition indicators that had the strongest relationship with SOC stock. The land condition indicators most closely correlated with SOC stocks across datasets and analysis scales were tree basal area, tree canopy cover, ground cover, pasture biomass and the density of perennial grass tussocks. In combination with soil type, these indicators accounted for up to 42% of the variation in the residuals after climate effects were removed. However, we found that responses often interacted with soil type, adding complexity and increasing the uncertainty associated with predicting SOC stock change at any particular location. We recommend that caution be exercised when considering SOC offset projects in northern Australian grazing lands due to the risk of incorrectly predicting changes in SOC stocks with change in land condition indicators and management activities for a particular paddock or property. Despite the uncertainty for generating SOC sequestration income, undertaking management activities to improve land condition is likely to have desirable complementary benefits such as improving productivity and profitability as well as reducing adverse environmental impact.

Climate Clever Beef: options to improve business performance and reduce greenhouse gas emissions in northern Australia

The Rangeland Journal – Climate Clever Beef special issue examines options for the beef industry in northern Australia to contribute to the reduction in global greenhouse gas (GHG) emissions and to engage in the carbon economy. Relative to its gross value (A$5 billion), the northern beef industry is responsible for a sizable proportion of national reportable GHG emissions (8–10%) through enteric methane, savanna burning, vegetation clearing and land degradation. The industry occupies large areas of land and has the potential to impact the carbon cycle by sequestering carbon or reducing carbon loss. Furthermore, much of the industry is currently not achieving its productivity potential, which suggests that there are opportunities to improve the emissions intensity of beef production. Improving the industry’s GHG emissions performance is important for its environmental reputation and may benefit individual businesses through improved production efficiency and revenue from the carbon economy. The Climate Clever Beef initiative collaborated with beef businesses in six regions across northern Australia to better understand the links between GHG emissions and carbon stocks, land condition, herd productivity and profitability. The current performance of businesses was measured and alternate management options were identified and evaluated. Opportunities to participate in the carbon economy through the Australian Government’s Emissions Reduction Fund (ERF) were also assessed. The initiative achieved significant producer engagement and collaboration resulting in practice change by 78 people from 35 businesses, managing more than 1 272 000 ha and 132 000 cattle. Carbon farming opportunities were identified that could improve both business performance and emissions intensity. However, these opportunities were not without significant risks, trade-offs and limitations particularly in relation to business scale, and uncertainty in carbon price and the response of soil and vegetation carbon sequestration to management. This paper discusses opportunities for reducing emissions, improving emission intensity and carbon sequestration, and outlines the approach taken to achieve beef business engagement and practice change. The paper concludes with some considerations for policy makers.

Preventing weed spread: a survey of lifestyle and commercial landholders about Nassella trichotoma in the Northern Tablelands of New South Wales, Australia

Nassella trichotoma (Nees) Hack. ex Arechav. (common name, serrated tussock) occupies large areas of south-eastern Australia and has considerable scope for expansion in the Northern Tablelands of New South Wales. This highly invasive grass reduces pasture productivity and has the potential to severely affect the region’s economy by decreasing the livestock carrying capacity of grazing land. Other potential consequences of this invasion include increased fuel loads and displacement of native plants, thereby threatening biodiversity. Rural property owners in the Northern Tablelands were sent a mail questionnaire that examined use of measures to prevent new outbreaks of the weed. The questionnaire was sent to professional farmers as well as lifestyle farmers (owners of rural residential blocks and hobby farms) and 271 responses were obtained (a response rate of 18%). Key findings were respondents’ limited capacity to detect N. trichotoma, and low adoption of precautions to control seed spread by livestock, vehicles and machinery. This was particularly the case among lifestyle farmers. There have been considerable recent changes to biosecurity governance arrangements in New South Wales, and now is an ideal time for regulators and information providers to consider how to foster regional communities’ engagement in biosecurity, including the adoption of measures that have the capacity to curtail the spread of N. trichotoma.

Rangeland profitability in the northern Gulf region of Queensland: understanding beef business complexity and the subsequent impact on land resource management and environmental outcomes

The farm-gate value of extensive beef production from the northern Gulf region of Queensland, Australia, is ~$150 million annually. Poor profitability and declining equity are common issues for most beef businesses in the region. The beef industry relies primarily on native pasture systems and studies continue to report a decline in the condition and productivity of important land types in the region. Governments and Natural Resource Management groups are investing significant resources to restore landscape health and productivity. Fundamental community expectations also include broader environmental outcomes such as reducing beef industry greenhouse gas emissions. Whole-of-business analysis results are presented from 18 extensive beef businesses (producers) to highlight the complex social and economic drivers of management decisions that impact on the natural resource and environment. Business analysis activities also focussed on improving enterprise performance. Profitability, herd performance and greenhouse emission benchmarks are documented and discussed.

Using Intelligent Agents to Understand Management Practices and Retail Productivity

Intelligent agents offer a new and exciting way of understanding the world of work. In this paper we apply agent-based modeling and simulation to investigate a set of problems in a retail context. Specifically, we are working to understand the relationship between human resource management practices and retail productivity. Despite the fact we are working within a relatively novel and complex domain, it is clear that intelligent agents could offer potential for fostering sustainable organizational capabilities in the future. The project is still at an early stage. So far we have conducted a case study in a UK department store to collect data and capture impressions about operations and actors within departments. Furthermore, based on our case study we have built and tested our first version of a retail branch simulator which we will present in this paper.

Understanding Retail Productivity by Simulating Management Practices

Intelligent agents offer a new and exciting way of understanding the world of work. In this paper we apply agent-based modeling and simulation to investigate a set of problems in a retail context. Specifically, we are working to understand the relationship between human resource management practices and retail productivity. Despite the fact we are working within a relatively novel and complex domain, it is clear that intelligent agents could offer potential for fostering sustainable organizational capabilities in the future. Our research so far has led us to conduct case study work with a top ten UK retailer, collecting data in four departments in two stores. Based on our case study data we have built and tested a first version of a department store simulator. In this paper we will report on the current development of our simulator which includes new features concerning more realistic data on the pattern of footfall during the day and the week, a more differentiated view of customers, and the evolution of customers over time. This allows us to investigate more complex scenarios and to analyze the impact of various management practices.

Comparing global land cover datasets through the Eagle matrix land cover components for continental Portugal

Global land cover maps play an important role in the understanding of the Earth's ecosystem dynamic. Several global land cover maps have been produced recently namely, Global Land Cover Share (GLC-Share) and GlobeLand30. These datasets are very useful sources of land cover information and potential users and producers are many times interested in comparing these datasets. However these global land cover maps are produced based on different techniques and using different classification schemes making their interoperability in a standardized way a challenge. The Environmental Information and Observation Network (EIONET) Action Group on Land Monitoring in Europe (EAGLE) concept was developed in order to translate the differences in the classification schemes into a standardized format which allows a comparison between class definitions. This is done by elaborating an EAGLE matrix for each classification scheme, where a bar code is assigned to each class definition that compose a certain land cover class. Ahlqvist (2005) developed an overlap metric to cope with semantic uncertainty of geographical concepts, providing this way a measure of how geographical concepts are more related to each other. In this paper, the comparison of global land cover datasets is done by translating each land cover legend into the EAGLE bar coding for the Land Cover Components of the EAGLE matrix. The bar coding values assigned to each class definition are transformed in a fuzzy function that is used to compute the overlap metric proposed by Ahlqvist (2005) and overlap matrices between land cover legends are elaborated. The overlap matrices allow the semantic comparison between the classification schemes of each global land cover map. The proposed methodology is tested on a case study where the overlap metric proposed by Ahlqvist (2005) is computed in the comparison of two global land cover maps for Continental Portugal. The study resulted with the overlap spatial distribution among the two global land cover maps, Globeland30 and GLC-Share. These results shows that Globeland30 product overlap with a degree of 77% with GLC-Share product in Continental Portugal.

Diversity and biotechnological potential of culturable bacteria from Brazilian mangrove sediment.

Mangrove ecosystems are environments subject to substantial degradation by anthropogenic activities. Its location, in coastal area, interfacing the continents and the oceans makes it substantially important in the prospection for biotechnological applications. In this study, we assessed the diversity of culturable bacteria present over the seasons at two depths (0-10 and 30-40 cm) in a mangrove sediment and in a transect area from the land to the sea. In total, 238 bacteria were isolated, characterized by Amplified Ribosomal DNA Restriction Analysis (ARDRA) and further identified, by Fatty Acid Methyl Esther (FAME-MIDI), into the orders of Vibrionales, Actinomycetales and Bacillales. Also the ability of the isolates in producing economically important enzymes (amylases, proteases, esterases and lipases) was evaluated and the order Vibrionales was the main enzymatic source.

Controle aplicado a poços com método de elevação e bombeio centrífugo submerso

The Electrical Submersible Pumping is an artificial lift method for oil wells employed in onshore and offshore areas. The economic revenue of the petroleum production in a well depends on the oil flow and the availability of lifting equipment. The fewer the failures, the lower the revenue shortfall and costs to repair it. The frequency with which failures occur depends on the operating conditions to which the pumps are submitted. In high-productivity offshore wells monitoring is done by operators with engineering support 24h/day, which is not economically viable for the land areas. In this context, the automation of onshore wells has clear economic advantages. This work proposes a system capable of automatically control the operation of electrical submersible pumps, installed in oil wells, by an adjustment at the electric motor rotation based on signals provided by sensors installed on the surface and subsurface, keeping the pump operating within the recommended range, closest to the well s potential. Techniques are developed to estimate unmeasured variables, enabling the automation of wells that do not have all the required sensors. The automatic adjustment, according to an algorithm that runs on a programmable logic controller maintains the flow and submergence within acceptable parameters avoiding undesirable operating conditions, as the gas interference and high engine temperature, without need to resort to stopping the engine, which would reduce the its useful life. The control strategy described, based on modeling of physical phenomena and operational experience reported in literature, is materialized in terms of a fuzzy controller based on rules, and all generated information can be accompanied by a supervisory system