Adaptive management for sound ecosystem management

Sound ecosystem management meshes socioeconomic attitudes and values with sustainable natural resource practices. Adaptive management is a model for guiding natural resource managers in this process. Ecosystems and the societies that use them are continually evolving. Therefore, managers must be flexible and adaptable in the face of uncertainty and lack of knowledge. To couple good science to management, it is important to develop goals, models, and hypotheses that allow us to systematically learn as we manage. Goals and models guide the development and implementation of management practices. The need to evaluate models and test hypotheses mandates monitoring, which feeds into a continuous cycle of goal and model reformulation. This paper reviews the process of adaptive management and describes how it is being applied to oak/pine savanna restoration at Necedah National Wildlife Refuge as an illustration. Our aim is to help managers design their own adaptive management models for successful ecosystem management.     

美国环保局的环境伙伴

通过统称为"环境伙伴"的一系列伙伴关系计划,美国环境保护局正在证实志愿目标与承诺能以一种及时和成本有效的方式达到真实的环境结果.志愿计划已经证明是一种预防污染、减少废物和提高能源效率的高度有效手段.通过这些努力,各公司正在实施新途径来改善其环境表现,且往往同时提高其基础水平.     

Resource availability and the abundance of an N-based defense in Australian tropical rain forests

Plant defense theories predict that relatively resource-rich environments (those with more fertile soil) will support a greater abundance of plants with nitrogen-based chemical defense, but this has yet to be adequately tested. We tested this prediction by measuring the diversity and contribution to total biomass of cyanogenic plants (those that release hydrogen cyanide from endogenous cyanide-containing compounds) in the Australian tropical rain forest. We examined 401 species in thirty 200-m2 plots, six at each of five sites, for cyanogenesis. In upland/highland rain forest, two pairs of sites similar in rainfall and altitude, but differing in soil nutrients, were selected, as well as one site in lowland rain forest. Sites differed markedly in species composition and foliar N was positively related to soil fertility. Holding altitude constant, we did not detect significant differences in the proportion of cyanogenic species with soil fertility, nor did we consistently detect significant increases in the contribution of cyanogenic species to total biomass on higher nutrient sites. Thus we found no clear evidence that soil fertility affects the distribution and prevalence of species investing in a constitutive N-based defense at the community level.     

Community social capital and individual functioning in the post‐disaster context

Disasters can have severe and long‐lasting consequences for individuals and communities. While scholarly evidence indicates that access to social support can ameliorate their negative impacts, less understood is whether or not neighbourhood social capital can facilitate recovery. This study uses two waves of survey data—collected before and after a significant flood in Brisbane, Australia, in 2011—to examine the relationship between the severity of the event at the individual and neighbourhood level, access to neighbourhood social capital and individual‐level social support, and functioning in the post‐disaster environment. In line with previous research, the results indicate that the severity of the flood is the most salient predictor of post‐disaster functioning. No evidence was unearthed to show that neighbourhood social capital amassed before the flood leads to better functioning subsequently, but the findings do suggest that individual‐level social support can moderate the effect of flood severity on functioning.     

Plant growth rates and seed size: a re-evaluation

Small-seeded plant species are often reported to have high relative growth rate or RGR. However, because RGR declines as plants grow larger, small-seeded species could achieve higher RGR simply by virtue of their small size. In contrast, size-standardized growth rate or SGR factors out these size effects. Differences in SGR can thus only be due to differences in morphology, allocation, or physiology. We used nonlinear regression to calculate SGR for comparison with RGR for 10 groups of species spanning a wide range of life forms. We found that RGR was negatively correlated with seed mass in nearly all groups, but the relationship between SGR and seed mass was highly variable. We conclude that small-seeded species only sometimes possess additional adaptations for rapid growth over and above their general size advantage.