Historical framework to explain long-term coupled human and natural system feedbacks: application to a multiple-ownership forest landscape in the northern Great Lakes region, USA

Current and future human and forest landscape conditions are influenced by the cumulative, unfolding history of social-ecological interactions. Examining past system responses, especially unintended consequences, can reveal valuable insights that promote learning and adaptation in forest policy and management. Temporal couplings are complex, however; they can be difficult to trace, characterize, and explain. We develop a framework that integrates environmental history into analysis of coupled human and natural systems (CHANS). Our study demonstrates how historical data and methods can help to explain temporal complexity of long-term CHANS feedbacks. We focus on two sources of temporal complexity: legacy effects and lagged interactions. We apply our framework to a multiple-ownership forest landscape comprising tribal and nonindustrial private forest ownerships in Wisconsin. Our framework features four elements that help investigators better understand complex systems through time: (1) a temporal axis parsed into historical periods (periodization), (2) representation of links between historical periods and system feedbacks, (3) representation of land ownership history, and (4) nested geographical scales of historical analysis. The framework can help to reveal legacy effects and lagged interactions, illuminate turning points and periods in system dynamics, and distil insights from unintended consequences that inform institutional and policy adaptation. We also assess the validity of using land ownership to represent the social component of CHANS models. When treated as a categorical variable and interpreted in historical context, land ownership can validly represent decision-making structure, culture, and knowledge system in spatially explicit social-ecological models

Heterogeneity of diabetes outcomes among asians and pacific islanders in the US: the diabetes study of northern california (DISTANCE).

ObjectiveEthnic minorities with diabetes typically have lower rates of cardiovascular outcomes and higher rates of end-stage renal disease (ESRD) compared with whites. Diabetes outcomes among Asian and Pacific Islander subgroups have not been disaggregated.Research design and methodsWe performed a prospective cohort study (1996-2006) of patients enrolled in the Kaiser Permanente Northern California Diabetes Registry. There were 64,211 diabetic patients, including whites (n = 40,286), blacks (n = 8,668), Latinos (n = 7,763), Filipinos (n = 3,572), Chinese (n = 1,823), Japanese (n = 951), Pacific Islanders (n = 593), and South Asians (n = 555), enrolled in the registry. We calculated incidence rates (means ± SD; 7.2 ± 3.3 years follow-up) and created Cox proportional hazards models adjusted for age, educational attainment, English proficiency, neighborhood deprivation, BMI, smoking, alcohol use, exercise, medication adherence, type and duration of diabetes, HbA(1c), hypertension, estimated glomerular filtration rate, albuminuria, and LDL cholesterol. Incidence of myocardial infarction (MI), congestive heart failure, stroke, ESRD, and lower-extremity amputation (LEA) were age and sex adjusted.ResultsPacific Islander women had the highest incidence of MI, whereas other ethnicities had significantly lower rates of MI than whites. Most nonwhite groups had higher rates of ESRD than whites. Asians had ~60% lower incidence of LEA compared with whites, African Americans, or Pacific Islanders. Incidence rates in Chinese, Japanese, and Filipinos were similar for most complications. For the three macrovascular complications, Pacific Islanders and South Asians had rates similar to whites.ConclusionsIncidence of complications varied dramatically among the Asian subgroups and highlights the value of a more nuanced ethnic stratification for public health surveillance and etiologic research

The Evaluation of Metals and Other Substances Released into Coal Mine Accrual Waters on the Wasatch Plateau Coal Field, Utah

Six sites on the Wasatch Plateau were chosen representing subsurface coal mines which were discharging or collecting accrual water on this coal field. Water samples were collected monthly at these sites for a period of 1 year (May 1981 to April 1982). Samples were taken before and after each mine\u27s treatment system. Water sampels were analyzed for major anions and cations, trace metals, physical properaties, nutrients, total organic carbon, oil and grease, trihalomethanes, and algal assay. Predictions were made as to the possible effects these coal mine accrual waters would have when used for drinking water, irrigation water, stock and wildlife watering, and as discharges into freshwater aquatic ecosystems. Compliance of the mine water discharges with NPDES regulations was also noted. Crushed coal samples were obtained from each of the six mine sites and evaluated with regard to their leaching characteristics in laboratory upflow leaching columns using an aqueous leaching medium characteristic of the area\u27s water supplies. Leachate samples were anlyzed for major anions and cations, trace metals, physical properaties, and total organic carbon. laboratory leaching characteristics were compared to the chemical nature of the actual mine water discharges. Mine water discharges were not found to be acidic in nature, the values for most parameters monitored during the field and laboratory portions of the study fell below the toxicity criteria for uses mentioned above, and were generally in compliance with NPDES regulations. Boron was present in the mine waters, but at levels which would be predicted to cause only minor or no damage to the most sensitive crops. The drinking water limit and the freshwater aquatic life bioaccumulation criterion for mercury were exceeded on several occasions in the coal mine accrual waters sampled. A comprehensive study of fish tissue samples and water samples taken from bodies of water near coal mines is recommended. Total suspended solids (TSS) and oil and grease were among the most frequently violated parameters with regard to NPDES regulations. Further studies are recommended with regard to the effects of these substances on stream biota, their sources and their rate in aquatic ecosystems. Coal leaching trends in the laboratory column experiments pralleled many of the trends observed in the field data collected. Trends for pH, aluminum, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, molybdenum, nickel, silver, zinc, boron, lithium, strontium, alkalinity, chloride, cluoride, potassium, sodium, and silica were generally consistent when these comparisons were made. Values for water hardness parameters were observed to be specific to the mine site involved and not always comparable to laboratory leachate column data. Generalizations with respect to leaching trends and origins of chemical substances in coal mine accrual waters must be made with caution due to the great potential variability in coal samples and the complexity of leaching phenomena