PREDICTING PEAK STREAM FLOW FROM AN UNDISTURBED WATERSHED IN THE CENTRAL APPALACHIANS1

ABSTRACT: Data from a small forested catchment were used to model peak stream flow as a function of basic hydrologic variables associated with 112 rain storms. Rainfall depth and initial stream flow rate accounted for 87.1 percent of peak flow variability. Forty expressions of rainfall intensity (describing both the temporal sequence of intensity for 20 equal storm intervals, and maximum intensity for 20 separate interval lengths) were used in an attempt to improve the predictability of basic models. None of the intensity parameters improved predictability by as much as 2 percent, apparently because the most intense rainfall bursts generally occurred near the beginning of storm periods. Mean rainfall intensity for entire storms was generally as effective as any of the shorter interval intensities, and its use helped to linearize the relationship between peak flow and rainfall depth and duration.     

EVALUATION OF INFLOW TO MIRROR LAKE,NEW HAMPSHIRE1

ABSTRACT: Measured stream discharge plus calculated ground water discharge (total measured runoff) were compared with runoff calculated by the unit-runoff method for the two largest watersheds of Mirror Lake for 1981–1983. Runoff calculated by the unit-runoff method, using Hubbard Brook watershed 3 as the index watershed, was greater than the total measured runoff into Mirror Lake during periods of high flow and slightly less than the total measured runoff into Mirror Lake during periods of low flow. Annual calculated unit runoff was 17 to 37 percent greater than total measured runoff. Differences in monthly runoff are far greater, ranging from 0 to greater than 100 percent. For high flows the calculated unit runoff is about 2 times greater than total measured runoff. For low flows the northwest basin of Mirror Lake has the greatest ground water contribution compared to the other two basins. In contrast, Hubbard Brook watershed 3 has the least ground water contribution.     

FLOOD FREQUENCY ANALYSIS FOR EVALUATING WATERSHED CONDITIONS WITh RAINFALL-RUNOFF MODELS1

ABSTRACT: Many rainfall-runoff modeling studies compare flood quantiles for different land-use and/or flood mitigation scenarios. However, when flood quantiles are estimated using conventional statistical methods, comparisons may be misleading because the estimates often misrepresent the quantile relationship between scenarios. An alternate statistical procedure is proposed, in which rainfall-runoff modeling is used to evaluate an approximate relationship between flood quantiles for different scenarios. Monte Carlo experiments show that the proposed method produces flood quantile estimates that better reflect the differences between scenarios. The ratio between quantiles for different scenarios is more accurate, so comparisons of the scenarios using flood quantiles are more reliable.     

Mentoring with(in) care: A co‐constructed auto‐ethnography of mutual learning

Research into workplace mentoring is principally focussed on predictors and psychosocial and instrumental outcomes, while there is scarcely any in‐depth research into relational characteristics, outcomes and processes. This article aims to illustrate these relational aspects. It reports a co‐constructed auto‐ethnography of a dyadic mentoring relationship as experienced by mentor and protégé. The co‐constructed narrative illustrates that attentiveness towards each other and a caring attitude, alongside learning‐focussed values, promote a high‐quality mentoring relationship. This relationship is characterised, among other things, by person centredness, care, trust and mutual influence, thereby offering a situation in which mutual learning and growth can occur. Learning develops through and in relation and is enhanced when both planned and unplanned learning takes place. In addition, the narrative makes clear that learning and growth of both those involved are intertwined and interdependent and that mutual learning and growth enrich and strengthen the relationship. It is concluded that the narrative illustrates a number of complex relational processes that are difficult to elucidate in quantitative studies and theoretical constructs. It offers deeper insight into the initiation and improvement of high‐quality mentoring relationships and emphasises the importance of further research into relational processes in mentoring relationships. Copyright © 2015 John Wiley & Sons, Ltd.     

BANKFULL HYDRAULIC GEOMETRY RELATIONSHIPS AND RECURRENCE INTERVALS FOR NORTH CAROLINA'S COASTAL PLAIN1

ABSTRACT: Bank full hydraulic geometry relationships relate stream channel geometry to watershed size for specific physiographic regions. This paper presents bank full hydraulic geometry relationships and recurrence intervals for the Southeastern Plain coercion and the flat woods subtype of the Middle Atlantic Coastal Plain ecoregion found within North Carolina's Coastal Plain physiographic province. Cross‐sectional and longitudinal survey data from gated and unpaged streams were used to compute channel dimension and profile information. Power functions were developed, relating drainage area to bank full discharge, cross‐sectional area, width, and mean depth. Recurrence intervals of bank full events were estimated from gagged streams using both a Log‐Pearson Type III distribution of peak annual discharge and a partial‐duration series of average daily discharge. Results from both methods indicate that average bank full recurrence intervals for the study area are below one year. Determinations of recurrence intervals by the Log‐Pearson Type III distribution were for the most part inconclusive (less than one year), while a partial duration series estimated a 0.19 year average, ranging from 0.11 to 0.31 years.     

Predation and aggressiveness in host plant protection: a generalization using ants from the genus Azteca

In studying the ant genus Azteca, a Neotropical group of arboreal species, we aimed to determine the extent to which the ants use predation and/or aggressiveness to protect their host plants from defoliating insects. We compared a territorially dominant, carton-nester, Azteca chartifex, and three plant-ant species. Azteca alfari and Azteca ovaticeps are associated with the myrmecophyte Cecropia (Cecropiaceae) and their colonies shelter in its hollow branches; whereas Azteca bequaerti is associated with Tococa guianensis (Melastomataceae) and its colonies shelter in leaf pouches situated at the base of the laminas. Whereas A. bequaerti workers react to the vibrations transmitted by the lamina when an alien insect lands on a leaf making it unnecessary for them to patrol their plant, the workers of the three other species rather discover prey by contact. The workers of all four species use a predatory behaviour involving spread-eagling alien insects after recruiting nestmates at short range, and, in some cases, at long range. Because A. alfari and A. ovaticeps discard part of the insects they kill, we deduced that the workers' predatory behaviour and territorial aggressiveness combine in the biotic defence of their host tree.     

城市绿地削减降雨地表径流污染效应的试验研究

针对城市降雨地表径流造成的非点源污染已成为城市收纳水体水质恶化和生态退化的主要因素这一现状,利用室内土壤柱模拟城市绿地对典型降雨地表径流污染的削减效应,研究土地覆被、径流污染物浓度、土层厚度以及水力负荷与停留时间对污染削减率的影响.结果表明,在低、中和高3种典型降雨地表径流污染浓度水平(COD为44.5、144.3、487.2 mg.L-1;NH4+-N为4.27、11.44、36.61 mg.L-1;TP为0.98、2.85、9.66 mg.L-1),8.15、7.13和6.12 cm.h-1的进水负荷持续1 h条件下,城市绿地的污染削减能力良好、稳定,对照组对COD、NH4+-N和TP的平均削减率分别达到33.41%~37.14%、58.74%~61.49%和63.65%~67.08%;受复氧能力和水力停留时间的限制,绿地覆被植物对污染物削减率的影响不明显;随着降雨地表径流污染浓度水平的增加,绿地的污染综合削减率保持在50%~60%左右,略有增大趋势;绿地对降雨地表径流污染的削减主要发生在深度50~70 cm的土层之上.     

Studies on the Uptake of Heavy Metals by Various Plant Species on Chromite Minespoils in Sub-tropical Regions of India

The presence of heavy metals (Cr, Ni and Fe) in soil and accumulated by herbs, shrubs and trees regenerated naturally on the minewaste-dumps of Sukinda chromite mines (TISCO sector) were investigated. There was significant correlationship between Cr and Fe in the soil where a tree species (Catunaregam spinosa) occurred. Guazuma ulmifolia and Diospyros montana also did show significant correlation between leaf, stem and soil for Cr, Ni and Fe. Among the shrubs (Calotropis gigantea, Chromolaena odorata, Phyllanthus reticulatus and Woodfordia fruticosa) significant and positive correlations were obtained for Cr and Ni in soil and iron and nickel in leaf and chromium and nickel in stem. Among the annual herbs, whole plant of tephrosia purpurea and Borrevia articularis showed significant and positive correlation with chromium and nickel with the maximum correlation coefficient value. It was concluded that the above information would be useful in revegetation programmes in subtropical regions having seasonal rainfall.     

Sharing goals by timely communication improves fishermen's satisfaction with marine protected areas: A case study in the Mediterranean

Marine protected areas (MPAs) are considered as a valid tool for mitigating the impact of fishing on marine ecosystems. Their success depends upon their acceptance by implicated stakeholders and on the integration of the stakeholder groups into their management. This integration is especially important with regard to fishermen, whose interests are the most directly affected by MPAs. The relational coordination method posits that effective communication and supportive relationships among stakeholders result in positive stakeholder behaviors and a more effective management of the system. Applying its principles, we designed a survey to evaluate the satisfaction of fishermen associated with five MPAs in the Spanish Mediterranean and determine what mechanisms affect fishermen’s acceptance of MPAs. Our results demonstrate that effective communication is particularly important for good supportive relationships and satisfaction among fishermen and other stakeholder groups, as well as satisfaction with the MPA. Sharing objectives with fishermen through timely communication is the primary mechanism to improve fishermen''s satisfaction and ameliorate perceptions towards MPA. To address this issue, we recommend more substantial integration of fishermen in the co-management of MPAs.     

Releasing characteristics of phosphorus and other substances during thermal treatment of excess sludge

The releasing characteristics of phosphorus,nitrogen compounds,organics,and some metal cations during thermal treatment of excess sludge were investigated.It was found that during heating not only phosphorus,but also nitrogen compounds,organics,and some metal cations could be released in abundance.The maximum orthophosphate (ortho-P) release of about 90 mg/L in concentration was observed at 50℃in 1 h.Except for volatile fatty acids (VFAs),comparatively little total nitrogen (TN),total organic carbon (TOC),and metal cations were released at the same time.Such results might favor further process of phosphorus recovery.VFAs were considerably released only at 50℃.Acetic,butyric,and propionic acid were the most abundant components in turn and their releasing profiles exhibited good linear relationship with time (R~2=0.9977,0.9624,and 0.8908,respectively).The concentrations of Mg~(2 ) and K~ increased with time and temperature during thermal treatment,but Ca~(2 ) decreased.The release of Mg~(2 ) and K~ agreed well with TP release (R~2=0.9892 and 0.9476,respectively).Temperature in the experimental range had very little impact on the linear relationships, especially of Mg~(2 ).Moreover,the parameter of mixed liquor suspended solids (MLSS) was found to be an important factor for thermal sludge treatment as the released ortho-P and total phosphorus (TP) at 50℃increased more than one-fold when MLSS was increased from 4000 to 8000 mg/L.