Wildlife impacts and vulnerable livelihoods in a transfrontier conservation landscape

Interactions between humans and wildlife resulting in negative impacts are among the most pressing conservation challenges globally. In regions of smallholder livestock and crop production, interactions with wildlife can compromise human well-being and motivate negative sentiment and retaliation toward wildlife, undermining conservation goals. Although impacts may be unavoidable when human and wildlife land use overlap, scant large-scale human data exist quantifying the direct costs of wildlife to livelihoods. In a landscape of global importance for wildlife conservation in southern Africa, we quantified costs for people living with wildlife through a fundamental measure of human well-being, food security, and we tested whether existing livelihood strategies buffer certain households against crop depredation by wildlife, predominantly elephants. To do this, we estimated Bayesian multilevel statistical models based on multicounty household data (n = 711) and interpreted model results in the context of spatial data from participatory land-use mapping. Reported crop depredation by wildlife was widespread. Over half of the sample households were affected and household food security was reduced significantly (odds ratio 0.37 [0.22, 0.63]). The most food insecure households relied on gathered food sources and welfare programs. In the event of crop depredation by wildlife, these 2 livelihood sources buffered or reduced harmful effects of depredation. The presence of buffering strategies suggests a targeted compensation strategy could benefit the region's most vulnerable people. Such strategies should be combined with dynamic and spatially explicit land-use planning that may reduce the frequency of negative human–wildlife impacts. Quantifying and mitigating the human costs from wildlife are necessary steps in working toward human–wildlife coexistence.     

不同碳源条件下草菇内切型纤维素酶基因(egl)转录表达的分析

利用Northern blot方法分析了不同碳源条件下草菇內切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10 d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12 h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d 8)可见eg1的表达,d 12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用. 图4 参14     

Resource users as land-sea links in coastal and marine socioecological systems

Coastal zones, which connect terrestrial and aquatic ecosystems, are among the most resource-rich regions globally and home to nearly 40% of the global human population. Because human land-based activities can alter natural processes in ways that affect adjacent aquatic ecosystems, land-sea interactions are increasingly recognized as critical to coastal conservation planning and governance. However, the complex socioeconomic dynamics inherent in coastal and marine socioecological systems (SESs) have received little consideration. Drawing on knowledge generalized from long-term studies in Caribbean Nicaragua, we devised a conceptual framework that clarifies the multiple ways socioeconomically driven behavior can link the land and sea. In addition to other ecosystem effects, the framework illustrates how feedbacks resulting from changes to aquatic resources can influence terrestrial resource management decisions and land uses. We assessed the framework by applying it to empirical studies from a variety of coastal SESs. The results suggest its broad applicability and highlighted the paucity of research that explicitly investigates the effects of human behavior on coastal SES dynamics. We encourage researchers and policy makers to consider direct, indirect, and bidirectional cross-ecosystem links that move beyond traditionally recognized land-to-sea processes.     

UNCERTAINTY ANALYSIS OF RUNOFF ESTIMATES FROM A RUNOFF CONTOUR MAP1

ABSTRACT: The U.S. Environmental Protection Agency (EPA) in cooperation with the U.S. Geological Survey (USGS) conducted an analysis to quantify the uncertainty associated with interpolating runoff to specific sites using a runoff contour map. We interpolated runoff to 93 gaged watersheds from a runoff contour map using (1) hand interpolation to the watershed outlet, (2) a computer interpolation to the watershed outlet, and (3) hand interpolation to the watershed centroid. We compared the interpolated values to the actual gaged values and found that there was a bias in the average interpolated value for runoff estimated at basin outlets, with interpolated values being less than the actual. We found no significant difference between the hand interpolation method and the computer interpolation method except that the computer method tended to have higher variability due to factors inherent to the software used. There were no strong spatial correlations or regional patterns in the runoff interpolations, which indicates that there are no regional biases introduced in the development of the contour map. We determined that we could estimate runoff, on the average, within approximately 8.9 cm (3.5 in; 15 percent) of the measured value using the three methods. The results of this work indicate that runoff contour maps can he used in regional studies to estimate runoff to ungaged systems with quantifiable uncertainty.     

An Innovative Index for Evaluating Water Quality in Streams

A water quality index expressed as a single number is developed to describe overall water quality conditions using multiple water quality variables. The index consists of water quality variables: dissolved oxygen, specific conductivity, turbidity, total phosphorus, and fecal coliform. The objectives of this study were to describe the preexisting indices and to define a new water quality index that has advantages over these indices. The new index was applied to the Big Lost River Watershed in Idaho, and the results gave a quantitative picture for the water quality situation. If the new water quality index for the impaired water is less than a certain number, remediation—likely in the form of total maximum daily loads or changing the management practices—may be needed. The index can be used to assess water quality for general beneficial uses. Nevertheless, the index cannot be used in making regulatory decisions, indicate water quality for specific beneficial uses, or indicate contamination from trace metals, organic contaminants, and toxic substances.     

High-resolution computational fluid dynamics modelling of suspended shellfish structures

Aquaculture structures are responsible for flow disturbances that extend over a large range of scales. In the case of shellfish aquaculture, those scales extend from the size of an individual shellfish to the size of a whole farm with intermediate scales being the size of a shellfish structure or of a block of shellfish structures. The influence of block spacing and angle is investigated by the mean of a 2D high resolution computational fluid dynamics model. Block angle is found to be the main relevant parameter controlling to a large extent the mixing generated by the shellfish structures. Strong sensitivity is found for small angles. Nevertheless, it is shown that for a limited number of blocks, upstream turbulence still dominates the degree of the total mixing within the farm, and that total flow reduction is little affected by the orientation of the blocks. A simple analytical model is presented that predicts most of the numerical results.     

Satellite tagging of blue sharks (Prionace glauca) and other pelagic sharks off eastern Australia: depth behaviour, temperature experience and movements

Satellite telemetry was used to study the movements and behaviour of ten blue sharks and one individual each of shortfin mako, thresher and bigeye thresher off eastern Australia. The tracks showed latitudinal movements of up to 1,900 km, but none of the sharks travelled away from the eastern Australian region. Tracking periods did not exceed 177 days. All species showed oscillatory dive behaviour between the surface layers to as deep as 560–1,000 m. Blue sharks spent 35–58% of their time in <50 m depths and 10–16% of their time in >300 m. Of these four species, the bigeye thresher spent the least time in the surface layers and the most time at >300 m depth. All four species showed clear diel behaviour generally occupying shallower depths at night than during the day. Blue sharks were mainly in 17.5–20.0°C water, while the thresher sharks showed a more bimodal temperature distribution.     

Effect of liquid manure on the mole fraction of nitrous oxide evolved from soil containing nitrate

The same emission factor is applied to fertiliser N and manure N when calculating national N2O inventories. Manures and fertilisers are often applied together to meet the N needs of the crop, but little is known about potential interactions leading to an increase in denitrification rate or a change in the composition of the end-products of denitrification. We used the 15N gas-flux method in a laboratory experiment to quantify the effect of liquid manure (LM) application on the fluxes of N2 and N2O when the soil contained fertiliser 15NO3-. LM increased the mole fraction of N2O from 0.5 to 0.85 in the first 12 h after application. More than 94% of the N2O was from the reduction of NO3-, probably due to aerobic nitrate respiration as well as respiratory denitrification.     

Ambient aerosol sampling: Problems,goals and wind tunnel test results of hi-volume samplers

The area of ambient air sampling and its inherent problems and current goals are discussed in general. In particular, recently completed tests of the collection effectiveness of the Rocky Flats Hi-Volume Sampler are compared to previously completed tests of the Standard EPA Hi-Volume Sampler for a variety of field realistic conditions. Collection effectiveness is defined as the ratio of the aerosol collected on the collection substrates of the sampler to that collected by an isokinetic sampling system.The collection effectiveness of the Standard EPA Hi-Volume Sampler was determined as a function of particle size (5–50 μm) and sampler orientation (0° and 45°) at a base condition wind speed of 4.6 m/s and 8% relative turbulence intensity. The results indicated a strong effect of orientation on collection effectiveness at a sampling rate of 1416 l/min. Wind speed over the range of 1.5–4.6 m/s does not greatly influence the collection effectiveness of 15 μm particles. Free stream turbulence levels of 1 and 8% relative intensity has no effect upon collection characteristics.The collection effectiveness of the Rocky Flats Hi-Volume Sampler was determined as a function of particle size (1–34 μm), wind speed (1.52–12.19 m/s) and sampler orientation to the mean flow (0°, 45°, 180°). The results show the sampler, with an inlet flow rate of 880 l/min, has an inlet effectiveness that was a slight function of orientation angle for particles 1–10 μm with a larger effect seen for 20–34 μm; a strong effect of velocity was seen up to 5 m/s where a further increase showed only a slight decrease in effectiveness.The Microsorban-98 filter that is presently used in the Rocky Flats Sampler was tested for efficiency over the size range of particles from 0.01–1 μm and with three different face velocities using the sampler flow rates of 600, 800 and 1 000 l/min corresponding to pressure drops of 20–24 in. of water (3.74–4.49 cm HaG). The filter paper, which was of the fiber type, was found to be 99.9% efficient over the range of particle sizes and pressure drops tested.