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Sea-level rise (SLR) is one of the greatest future threats to mangrove forests. Mangroves have kept up with or paced past SLR by maintaining their forest floor elevation relative to sea level through root growth, sedimentation, and peat development. Monitoring surface elevation change (SEC) or accretion rates allows us to understand mangrove response to SLR and prioritizes resilient ecosystems for conservation or vulnerable ecosystems for restoration. We compared three methods to measure SEC and accretion in mangrove forests: 210Pb, surface elevation tables (SETs), and a terrestrial light detection and ranging system (compact biomass LiDAR—CBL). Lead-210 accretion rates were not significantly different than SET SEC rates and differences between the two methods (− 2 to 2 mm/year) were within the error of our measurements. Lead-210 only measures accretion in the upper meter of sediment and cannot capture deeper subsurface processes (e.g., subsidence, compaction) that SETs can. The lack of differences suggests the following: (1) surface processes in the active root zone are influencing forest floor elevation more than subsurface processes, (2) subsurface processes were not large enough to effect elevation, or (3) the SETs were not installed deep enough to capture subsurface processes. CBL SEC rates did not differ significantly from SET SEC rates. The larger spatial scale of the CBL scans resulted in significantly different SEC rates from some of the plots. This was due to the CBL measuring areas missed by the SET. The greater number of points measured by CBL (~ 30,000 vs 36) increased precision and lowered standard error. The traditional SET/rSET method is currently 3–10 × cheaper than the 210Pb or CBL method, respectively, and can accurately track changes in forest floor elevation. Costs of the use of LiDAR are likely to decrease in the future with the advent of newer and more cost-effective technology. [ABSTRACT FROM AUTHOR]

Understanding the developmental precursors of juvenile violent sex offending can contribute to the promotion of effective early intervention and prevention programs for high-risk children and youth. However, there is currently a lack of research on the early characteristics of adolescents who commit violent sex offenses. Drawing on the literature regarding the generalist and specialist positions of criminal behavior, the aim of the present study was to compare childhood risk factors for three groups of juvenile offenders: (a) pure sex offenders (PSO; n = 28); (b) violent non-sex offenders (VNSO; n = 172); and (c) versatile violent sex offenders (VVSO; n = 24). Nineteen risk factors comprising four life domains (individual, family, peer, and school) were identified from a file review. Three hierarchical logistic regression analyses examined associations between risk factors and offender groups. The results reflected the underlying heterogeneity of the sample, offering support for both the specialist and generalist positions of criminal behavior. PSOs differed from VNSOs on the basis of higher odds for precocious sexual behavior. Second, VVSOs differed from VNSOs on the basis of higher odds for precocious sexual behavior, criminal family members, and an adolescent mother, as well as lower odds for poor school behavior. Third, PSOs were marginally more likely to have engaged in early overt antisocial behavior compared with VVSOs. Fourth, many of the childhood risk factors examined were not associated with any offender group. In conclusion, VVSOs appeared to differ on the greatest number of risk factors from VNSOs, suggesting that VVSOs share a more similar developmental pathway with PSOs. The prevention and future research implications of these findings are discussed. (Contains 5 tables.)

This study surveyed elementary school teachers in Melbourne, Australia to investigate their knowledge about attention-deficit/hyperactivity disorder (ADHD) and its impact on their reported behavior toward and perceptions of children with ADHD. Consistent with previous international findings, teachers demonstrated good overall knowledge about ADHD, with strengths in knowledge of symptoms/diagnosis and weaknesses in knowledge of causes and treatments. To investigate how knowledge impacted reported behaviors and perceptions, teachers also read vignettes of children with ADHD symptoms and rated their reactions to these children. In general, teachers with high, and to some extent average, knowledge about ADHD reported more helpful behaviors (e.g., help-seeking for their students) and perceptions (e.g., perceive the benefit of behavioral and educational treatments). However, teachers with high and average knowledge also predicted that these children would be more disruptive in the classroom, and reported having less confidence in their ability to manage these children. Implications and need for future research are discussed. (Contains 4 tables.)

The coastal red mangrove, Rhizophora mangle L., was introduced to the Hawaiian Islands from Florida 100 yr ago and has spread to cover many shallow intertidal shorelines that once were unvegetated mudflats. We used a field survey approach to test whether mangroves at the land-ocean interface could indicate watershed inputs, especially whether measurements of leaf chemistry could identify coasts with high nutrient inputs and high mangrove productivities. During 2001-2002, we sampled mangroves on dry leeward coasts of southern Moloka'i and O'ahu for 14 leaf variables including stable carbon and nitrogen isotopes ([δ.sup.13]C, [δ.sup.15]N), macronutrients (C, N, P), trace elements (B, Mn, Fe, Cu, Zn), and cations (Na, Mg, K, Ca). A new modeling approach using leaf Na, N, P, and [δ.sup.13]C indicated two times higher productivity for mangroves in urban versus rural settings, with rural mangroves more limited by low N and P nutrients and high-nutrient urban mangroves more limited by freshwater inputs and salt stress. Leaf chemistry also helped identify other aspects of mangrove dynamics: especially leaf [δ.sup.15]N values helped identify groundwater N inputs, and a combination of strongly correlated variables (C, N, P, B, Cu, Mg, K, Ca) tracked the mangrove growth response to nutrient loading. Overall, the chemical marker approach is an efficient way to survey watershed forcing of mangrove forest dynamics., Mangrove coasts are being cleared and developed by humans, and current estimates are that more than 50% of mangrove forests have been lost already (Ong 1995, Valiela et al. 2001). [...]