The influence of concurrent disturbances on plant community dynamics in northern hemlock-hardwood forests

Throughout the Upper Great Lakes region, alterations to historic disturbance regimes have influenced plant community dynamics in hemlock-hardwood forests. Several important mesic forest species, eastern hemlock (Tsuga canadensis), yellow birch (Betula alleghaniensis), eastern white pine (Pinus strobus), and Canada yew (Taxus canadensis), are in decline due to exploitive logging practices used at the turn of the 20th century and the wave of intense fires that followed. Continued regeneration and recruitment failure is attributed to contemporary forest management practices and overbrowsing by white-tailed deer (Odocoileus virginianus). Therefore, I examined the influence of two concurrent disturbances, overstory removal and herbivory, on plant community dynamics in two hemlock-hardwood forests. I measured the post-disturbance regeneration response (herbaceous and woody species) inside and outside of deer exclosures in 20 artificial canopy gaps (50 – 450 m2) and monitored survival and growth for hundreds of planted seedlings. The results of this research show that interacting disturbances can play a large role in shaping plant community composition and structure in hemlock-hardwood forests. White-tailed deer herbivory homogenized the post-disturbance plant communities across the experimental gradient of gap areas, essentially making species compositions in small gaps “look like” those in large gaps. Deer browsing also influenced probability of survival for planted Canada yew cuttings; all else being equal an individual was nearly seven times more likely to survive if protected from herbivory (P < 0.001). In contrast, the ability of sugar maple (Acer saccharum) to persist under high levels of herbivory and respond rapidly to overstory release appears to be related to the presence of stem layering(i.e., portions of below-ground prostrate stem). Layering occurred in 52% of excavated saplings (n = 100) and was significantly associated with increased post-disturbance height growth. Understory light was also important to planted seedling establishment and height growth. Higher levels of direct under-canopy light negatively impacted survival for shade-tolerant hemlock and Canada yew, while an increase in diffuse light was linked to a higher probability of survival for yellow birch and height growth for hemlock and Canada yew. Increases in white pine height growth were also significantly associated with a decrease in canopy cover.

Sediment yield reduction in an agricultural watershed

With proper application of Best Management Practices (BMPs), the impact from the sediment to the water bodies could be minimized. However, finding the optimal allocation of BMP can be difficult, since there are numerous possible options. Also, economics plays an important role in BMP affordability and, therefore, the number of BMPs able to be placed in a given budget year. In this study, two methodologies are presented to determine the optimal cost-effective BMP allocation, by coupling a watershed-level model, Soil and Water Assessment Tool (SWAT), with two different methods, targeting and a multi-objective genetic algorithm (Non-dominated Sorting Genetic Algorithm II, NSGA-II). For demonstration, these two methodologies were applied to an agriculture-dominant watershed located in Lower Michigan to find the optimal allocation of filter strips and grassed waterways. For targeting, three different criteria were investigated for sediment yield minimization, during the process of which it was found that the grassed waterways near the watershed outlet reduced the watershed outlet sediment yield the most under this study condition, and cost minimization was also included as a second objective during the cost-effective BMP allocation selection. NSGA-II was used to find the optimal BMP allocation for both sediment yield reduction and cost minimization. By comparing the results and computational time of both methodologies, targeting was determined to be a better method for finding optimal cost-effective BMP allocation under this study condition, since it provided more than 13 times the amount of solutions with better fitness for the objective functions while using less than one eighth of the SWAT computational time than the NSGA-II with 150 generations did.

Diseases in neonatal foals. Part 1: the 30 day incidence of disease and the effect of prophylactic antimicrobial drug treatment during the first three days post partum

REASONS FOR PERFORMING STUDY: Neonatal diseases have been grouped and analysed but up-to-date statistically significant information about the incidence and prevalence of diseases in foals is limited. Since the 1950s it has been a common management practice to administer a 3 day course of antimicrobial drugs to neonatal foals. This was shown to significantly reduce the incidence of infections (Platt 1977). Since then management practices have improved and it is widely believed that prophylactic antimicrobial drugs are no longer necessary in foal rearing. OBJECTIVES: To determine the 30 day incidences or prevalences (depending on case definition) of various diseases and conditions in the neonatal foal and ascertain the influence of a prophylactic 3 day treatment on the frequency of infections. METHODS: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). Depending on the stud farm's practice in the use of prophylactic antimicrobial drugs, 2 groups of newborn foals (treated and untreated) were identified and followed for 30 days. RESULTS: The 30 day incidences of infectious diseases under study were between 0.2% (osteomyelitis) and 5.85% (systemic disease with diarrhoea). The overall incidence for 'total infectious diseases' was 8.27%. The most commonly observed noninfectious condition was limb deformities (12.11% of all foals). There was no significant difference in the incidence of infectious diseases between the 2 groups. CONCLUSION: Infectious diseases are still an important problem in neonatal foals requiring further investigation as to which factors other than antimicrobial prophylaxis are relevant for disease prevention. POTENTIAL RELEVANCE: The results provide an up-to-date overview about the frequencies of various neonatal foal diseases. They do not support the traditional prophylactic use of antimicrobials to prevent infectious diseases in healthy newborn foals. However, it should be noted that this study was not a randomised controlled trial and therefore does not provide the strongest possible evidence for this conclusion.

Engaging Local Communities in Low Emissions Land-Use Planning: a Case Study from Laos

Reducing Emissions from Deforestation and Forest Degradation and enhancing forest carbon stocks (REDD+) is a performance-based payment mechanism currently being debated in international and national environmental policy and planning forums. As the mechanism is based on conditionality, payments must reflect land stewards’ level of compliance with carbon-efficient management practices. However, lack of clarity in land governance and carbon rights could undermine REDD+ implementation. Strategies are needed to avoid perverse incentives resulting from the commoditization of forest carbon stocks and, importantly, to identify and secure the rights of legitimate recipients of future REDD+ payments. We propose a landscape-level approach to address potential conflicts related to carbon tenure and REDD+ benefit sharing. We explore various land-tenure scenarios and their implications for carbon ownership in the context of a research site in northern Laos. Our case study shows that a combination of relevant scientific tools, knowledge, and participatory approaches can help avoid the marginalization of rural communities during the REDD+ process. The findings demonstrate that participatory land-use planning is an important step in ensuring that local communities are engaged in negotiating REDD+ schemes and that such negotiations are transparent. Local participation and agreements on land-use plans could provide a sound basis for developing efficient measurement, reporting, and verification systems for REDD+.

Firms, do you know your currency risk exposure? Survey results

This paper surveys the currency risk management practices of Swiss industrial corporations. We find tha industrials do not quantify their currency risk exposure and investigate possible reasons. One possibility is that firms do not think they need to know because they use on-balance-sheet instruments to protect themselves before and after currency rates reach troublesome levels. This is puzzling because a rough estimate of at least cash flow exposure is not a prohibitive task and could be helpful. It is also puzzling that firms use currency derivatives to hedge/insure individual short-term transactions, without apparently trying to estimate aggregate transaction exposure.

Antibody Response to Inactivated Viral Vaccines Administered to Calves at Weaning

Respiratory disease in beef calves has been associated with the stress of weaning. Management practices commonly delay vaccination of calves to this time, and weaning stress could potentially suppress the immune response. To reduce this stress we have been experimenting with a procedure termed “pasture weaning” in which the dams are removed and the calves remain on pasture. Observation suggests that calves weaned with this approach adapt to the weaned state much better than those held in drylot. Consequently, one would expect less stress-mediated effects including those on the immune system. Calves were weaned and assigned to groups that were pasture or drylot weaned, and calves within the groups were vaccinated with one of two inactivated virus vaccines by either the intramuscular or subcutaneous route. Weaning placement did not affect antibody responses to the viruses included in the vaccines. The route of administration did not influence responses with subcutaneous injection inducing responses equivalent to the intramuscular site. Utilization of this route for vaccination could be advantageous because it precludes the tissue damage and hidden abscessation that sometimes results from intramuscular injections. A distinct difference was noted in the immunogenicity of the vaccines with the Vira Shield product yielding significantly better responses to all viral entities.

Vertical integration and information sharing — an empirical investigation in the German apparel industry

Despite the astounding success of the fast fashion retailers, the management practices leading to these results have not been subject to extensive research so far. Given this background, we analyze the impact of information sharing and vertical integration on the performance of 51 German apparel companies. We find that the positive impact of vertical integration is mediated by information sharing, i.e. that the ability to improve the information flow is a key success factor of vertically integrated apparel supply chains. Thus, the success of an expansion strategy based on vertical integration critically depends on effective ways to share logistical information.

Understanding the underlying mechanisms of recent Jatropha curcas L. adoption by smallholders in Kenya: A rural livelihood assessment in Bondo, Kibwezi, and Kwale districts

Between 2004 and 2007, NGOs, community based organisations and private investors promoted jatropha in Kenya with the aim of generating additional income and producing biofuel for rural development. By 2008 it became gradually evident that jatropha plantations (both mono- and intercropping) are uneconomical and risky due to competition for land and labour with food crops. Cultivation of jatropha hedges was found to have better chances of economic success and to present only little risks for the adopting farmers. Still, after 2008 a number of farmers went on adopting jatropha in plots rather than as hedges. It is hypothesised that lack of awareness about the low economic prospects of jatropha plantations was the main reason for continued adoption, and that smallholder farmers with higher resource endowments mainly ventured into its cultivation. In this study we provide an empirical basis for understanding the role of households' capital assets in taking up new livelihood strategies by smallholder farmers in three rural districts in Kenya. For that purpose, we assess the motivation and enabling factors that led to the adoption of jatropha as a new livelihood strategy, as well as the context in which promotion and adoption took place. A household survey was conducted in 2010, using a structured questionnaire, to collect information on household characteristics and capital asset endowment. Data were analysed using descriptive statistics and non-parametric statistical tests. We established that access to additional income and own energy supply were the main motivation for adoption of jatropha, and that financial capital assets do not necessarily have a positive influence on adoption as hypothesised. Further, we found that the main challenges that adopting farmers faced were lack of access to information on good management practices and lack of a reliable market. We conclude that continued adoption of on-farm jatropha after 2008 is a result of lacking awareness about the low economic value of this production type. We recommend abandoning on-farm production of jatropha until improved seed material and locally adapted agronomic knowledge about jatropha cultivation becomes available and its production becomes economically competitive.

A multiarm randomized field trial evaluating strategies for udder health improvement in Swiss dairy herds.

The aims of this study were to quantify the effectiveness of specialist advice about udder health in Swiss dairy herds and to compare 3 different udder health improvement strategies against a negative control group. In 2010, 100 Swiss dairy herds with a high (between 200,000 and 300,000 cells/mL) yield-corrected bulk milk somatic cell count (YCBMSCC) were recruited for a 1-yr multiarm randomized field trial. The herds were visited between September and December 2011 to evaluate udder health-management practices and then randomly allocated into 1 of 4 study arms containing 25 herds each. The negative control study arm received neither recommendations for improving udder health nor any active support. The remaining 75 farmers received a herd-specific report with recommendations to improve udder health management. The positive control study arm received no further active support during 2012. The veterinarian study arm received additional support in the form of monthly visits by their herd veterinarian. Finally, the study group study arm received support in the form of bimonthly study group meetings where different topics concerning udder health were discussed. One year later, implementation of recommendations and changes in udder health were assessed. Of the recommendations given, 44.3% were completely implemented, 23.1% partially, and 32.6% were not implemented. No differences in implementation of recommendations were noted between the 3 study arms. At study enrollment, farmers were asked for the study arm of their preference but were subsequently randomly assigned to 1 of the 4 study arms. Farmers that were assigned to the study arm of their preference implemented more recommendations than farmers assigned to a study arm not of their preference. No decrease in the within-herd prevalence of cows that had a high (≥200,000 cells/mL) composite somatic cell count was observed in herds that had a YCBMSCC ≥200,000 cells/mL at the start of intervention. However, the 3 study arms with intervention (positive control, the veterinarian, and the study groups) prevented an increase in the within-herd prevalence of cows that had a high somatic cell count in herds with a low YCBMSCC at the start of the intervention compared with the negative control study arm. In the year after sending the report, herds assigned to the study group study arm had a reduced incidence rate of treated mastitis cases in comparison with the year before sending the report.

Experimental evidence for the immediate impact of fertilization and irrigation upon the plant and invertebrate communities of mountain grasslands

The response of montane and subalpine hay meadow plant and arthropod communities to the application of liquid manure and aerial irrigation – two novel, rapidly spreading management practices – remains poorly understood, which hampers the formulation of best practice management recommendations for both hay production and biodiversity preservation. In these nutrient-poor mountain grasslands, a moderate management regime could enhance overall conditions for biodiversity. This study experimentally assessed, at the site scale, among low-input montane and subalpine meadows, the short-term effects (1 year) of a moderate intensification (slurry fertilization: 26.7–53.3 kg N·ha−1·year−1; irrigation with sprinklers: 20 mm·week−1; singly or combined together) on plant species richness, vegetation structure, hay production, and arthropod abundance and biomass in the inner European Alps (Valais, SW Switzerland). Results show that (1) montane and subalpine hay meadow ecological communities respond very rapidly to an intensification of management practices; (2) on a short-term basis, a moderate intensification of very low-input hay meadows has positive effects on plant species richness, vegetation structure, hay production, and arthropod abundance and biomass; (3) vegetation structure is likely to be the key factor limiting arthropod abundance and biomass. Our ongoing experiments will in the longer term identify which level of management intensity achieves an optimal balance between biodiversity and hay production.

Forests and water: Managing interrelations

Due to their biodiversity, forests generate a range of products and services that are of economic, social or cultural value to human beings. Natural resource management provisions should ensure the creation and maintenance of these goods and services in the long term. However, unsustainable management practices of forests do not only generate short-term benefits but also considerable costs for society. Payment by the beneficiaries of the services would enable us to internalise external costs and promote sustainable management. Two days of conferences on ”Forest and water”, on the multifunctionality of forests, on interactions between forests and water, on sustainable resource management, on payments for environmental services, their institutional and economic perspectives, were the basis of this brochure which presents an in-depth analysis of the information exchanged among conference participants and the public. It is intended for readers who work in international development cooperation and assistance in Switzerland and abroad. It offers additional information for local programmes in the field and at policy level.

Evaluation of soil salinity amelioration technologies in Timpaki, Crete

Salinization is a soil threat that adversely affects ecosystem services and diminishes soil functions in many arid and semi-arid regions. Soil salinity management depends on a range of factors, and can be complex expensive and time demanding. Besides taking no action, possible management strategies include amelioration and adaptation measures. The WOCAT Technologies Questionnaire is a standardized methodology for monitoring, evaluating and documenting sustainable land management practices through interaction with the stakeholders. Here we use WOCAT for the systematic analysis and evaluation of soil salinization amelioration measures, for the RECARE project Case Study in Greece, the Timpaki basin, a semi-arid region in south-central Crete where the main land use is horticulture in greenhouses irrigated by groundwater. Excessive groundwater abstractions have resulted in a drop of the groundwater level in the coastal part of the aquifer, thus leading to seawater intrusion and in turn to soil salinization due to irrigation with brackish water. Amelioration technologies that have already been applied in the case study by the stakeholders are examined and classified depending on the function they promote and/or improve. The documented technologies are evaluated for their impacts on ecosystem services, cost and input requirements. Preliminary results show that technologies which promote maintaining existing crop types while enhancing productivity and decreasing soil salinity such as composting, mulching, rain water harvesting and seed biopriming are preferred by the stakeholders. Further work will include result validation using qualitative approaches.

Stand scale variability of topsoil organic matter composition in a high-elevation Norway spruce forest ecosystem

Our knowledge about the effect of single-tree influence areas on the physicochemical properties of the underlying mineral soil in forest ecosystems is still limited. This restricts our ability to adequately estimate future changes in soil functioning due to forest management practices. We studied the stand scale spatial variation of different soil organic matter species investigated by 13C NMR spectroscopy, lignin phenol and neutral sugar analysis under an unmanaged mountainous high-elevation Norway spruce (Picea abies L.) forest in central Europe. Multivariate geostatistical approaches were applied to relate the spatial patterns of the different soil organic matter species to topographic parameters, bulk density, oxalate- and dithionite-extractable iron, pH, and the impact of tree distribution. Soil samples were taken from the mineral top soil. Generally, the stand scale distribution patterns of different soil organic matter compounds could be divided into two groups: Those compounds, which were significantly spatially correlated with topography/altitude and those with small scale spatial pattern (range ≤ 10 m) that was closely related to tree distribution. The concentration of plant-derived soil organic matter components, such as lignin, at a given sampling point was significantly spatially related to the distance of the nearest tree (p ≤ 0.05). In contrast, the spatial distribution of mainly microbial-derived compounds (e.g. galactose and mannose) could be attributed to the dominating impact of small-scale topography and the contribution of poorly crystalline iron oxides that were significantly larger in the central depression of the study site compared to crest and slope positions. Our results demonstrate that topographic parameters dominate the distribution of overall topsoil organic carbon (OC) stocks at temperate high-elevation forest ecosystems, particularly in sloped terrain. However, trees superimpose topography-controlled OC biogeochemistry beneath their crown by releasing litter and changing soil conditions in comparison to open areas. This may lead to distinct zones with different mechanisms of soil organic matter degradation and also stabilization in forest stands.

Isolation and Characterization of a Microorganism from Groundwater that Reduces Arsenate

This is an investigation into the microbially mediated processes involved in the transformation of arsenic. With the recent change in the Federal Maximum Contaminant Level for arsenic in drinking water, an increasing amount of resources are being devoted to understanding the mechanisms involved in the movement of arsenic. Arsenic in drinking water typically comes from natural sources, but the triggers that result in increased release of arsenic from parent material are poorly understood. Knowledge of these processes is necessary in order to make sound engineering decisions regarding drinking water management practices. Recent years have brought forth the idea that bacteria play a significant role in arsenic cycling. Groundwater is a major source of potable water in this and many other countries. To date, no reports have been made indicating the presence and activity of arsenate reducing bacteria in groundwater settings, which may increase dissolved arsenic concentrations. This research was designed to address this question and has shown that these bacteria are present in Maine groundwater. Two Maine wells were sampled in order to culture resident bacteria that are capable of dissimilatory arsenate reduction. Samples were collected using anaerobic techniques fiom wells in Northport and Green Lake. These samples were amended with specific compounds to enrich the resident population of arsenate utilizing bacteria. These cultures were monitored over time to establish rates of arsenate reduction. Cultures fiom both sites exhibited arsenate reduction in initial enrichment cultures. Isolates obtained fiom the Green Lake enrichments, however, did not reduce arsenate. This indicates either that a symbiotic relationship was required for the observed arsenate reduction or that fast-growing fermentative organisms that could survive in high arsenate media were picked in the isolation procedure. The Northport cultures exhibited continued arsenate reduction after isolation and successive transfers into fiesh media. The cultured bacteria reduced the majority of 1 a arsenate solutions in less than one week, accompanied by a corresponding oxidation of lactate. The 16s rRNA fiom the isolate was arnplifled and sequenced. The results of the DNA sequence analysis indicate that the rRNA sequence of the bacteria isolated at the Northport site is unique. This means that this strain of bacteria has not been reported before. It is in the same taxonomic subgroup as two previously described arsenate respirers. The implications of this study are significant. The fact that resident bacteria are capable of reducing arsenate has implications for water management practices. Reduction of arsenate to arsenite increases the mobility of the compound, as well as the toxicity. An understanding of the activity of these types of organisms is necessary in order to understand the contribution they are making to arsenic concentrations in drinking water. The next step in this work would be to quantitj the actual loading of dissolved arsenic present in aquifers because of these organisms.

Occupational beryllium exposure: Reconciling federal policies, regulations and contractor implementation guides to protect worker health

Beryllium is a widely distributed, highly toxic metal. When beryllium particulates enter the body, the body's defense mechanisms are engaged. When the body's defenses cannot easily remove the particulates, then a damage and repair cycle is initiated. This cycle produces chronic beryllium disease (CBD), a progressive, fibrotic respiratory involvement which eventually suffocates exposed individuals. ^ Beryllium disease is an occupational disease, and as such it can be prevented by limiting exposures. In the 1940s journalists reported beryllium deaths at Atomic Energy Commission (AEC) facilities, the Department of Energy's (DOE) predecessor organization. These reports energized public pressure for exposure limits, and in 1949 AEC implemented a 2 μg/m3 permissible exposure limit (PEL). ^ The limits appeared to stop acute disease. In contrast, CBD has a long latency period between exposure and diagnosable disease, between one and thirty years. The lack of immediate adverse health consequences masked the seriousness of chronic disease and pragmatically removed CBD from AEC/DOE's political concern. ^ Presently the PEL for beryllium at DOE sites remains at 2 μg/m 3. This limit does not prevent CBD. This conclusion has long been known, although denied until recently. In 1999 DOE acknowledged the limit's ineffectiveness in its federal regulation governing beryllium exposure, 10 CFR 850. ^ Despite this admission, the PEL has not been reduced. The beryllium manufacturer and AEC/DOE have a history of exerting efforts to maintain and protect the status quo. Primary amongst these efforts has been creation and promotion of disinformation within peer reviewed health literature which discusses beryllium, exposures, health effects and treatment, and targeting graduate school students so that their perspective is shaped early. ^ Once indoctrinated with incorrect information, professionals tend to overlook aerosol and respiratory mechanics, immunologic and carcinogenic factors. They then apply tools and perspectives derived from the beryllium manufacturer and DOE's propaganda. Conclusions drawn are incorrect. The result is: health research and associated policy is conducted with incorrect premises. Effective disease management practices are not implemented. ^ Public health protection requires recognition of the disinformation and its implications. When disinformation is identified, then effective health policies and practices can be developed and implemented. ^