Land use change from rainforests to oil palm plantations and food gardens in Papua New Guinea: Effects on soil properties and S fractions

Changes in soil sulfur (S) fractions were assessed in oil palm and food garden land use systems developed on forest vegetation in humid tropical areas of Popondetta in northern Province. The study tested a hypothesis that S in food gardens are limiting nutrient factor and are significantly lower than in plantations and forests. Subsistence food gardens are under long-term slash and burn practice of cropping and such practice is expected to accelerate loss of biomass S from the ecosystem. From each land use, surface soil (0–15 cm) samples were characterised and further pseudocomplete fractionated for S. Conversion of forest to oil palm production decreased (p0.001) soil pH and electrical conductivity values. The reserve S fraction in soil increased significantly (p0.05) due to oil palm production (∼ 28 %) and food gardening activity (∼ 54 %). However, plant available SO42--S was below 15 mg kg^(−1) in the food garden soils and foliar samples of sweet potato crop indicating deficiency of plant available S. Soil organic carbon content (OC) was positively and significantly correlated to total S content (r=0.533; p0.001) among the land use systems. Thus, crop management practices that affect OC status of the soils would potentially affect the S availability in soils. The possible changes in the chemical nature of mineralisable organic S compounds leading to enhanced mineralisation and leaching losses could be the reasons for the deficiency of S in the food garden soils. The results of this study conclude that long-term subsistence food gardening activity enriched top soils with reserve S or total S content at the expense of soluble S fraction. The subsistence cropping practices such as biomass burning in food gardens and reduced fallow periods are apparently threatening food security of oil palm households. Improved soil OC management strategies such as avoiding burning of fallow vegetation, improved fallows, mulching with fallow biomass, use of manures and S containing fertilisers must be promoted to sustain food security in smallholder oil palm system

GIS‑assisted flood‑risk potential mapping of Ilorin and its environs, Kwara state, Nigeria

DATA AVAILABITY STATEMENT: The authors confirm that the data supporting the findings of this study are available within the article.The incessant reoccurrence of flooding disasters across Nigeria has mandated an urgent outlook on food-risk management techniques. Ilorin and its environs have suffered immensely from annual food reoccurrence. This study aims to assess food risk within Ilorin and its environs and proffer adequate food mitigation strategies that governments and policymakers can adopt to placate future flooding events within the state. Satellite imagery data were acquired and analyzed for food-risk assessment of the area. Ten highly influential food causative factors were synergized using Multi-Criteria Decision-Making techniques in this research; they are Land Surface Temperature, Elevation, Soil Moisture Index, and Distance to Stream, Drainage Density, Stream Power Index, Normalized Difference Vegetation Index, Land Use Land Cover, Slope, and Topographic Wetness Index. Findings showed that approximately 47.2% of the study area had low food risk, while moderate and high food-risk zones occupied 33.5% and 19.29%, respectively. Most parts of Ilorin and its environs are safe from food disasters; only about one-quarter of the total area under investigation lies in the high food-risk zones; these areas mostly fall within the shores of major streams, rivers, and dams within the state. A plot of previous food cases in the state placed the affected areas in the high and moderate zones of food risk, confirming the efficacy of geospatial techniques in food-risk assessment. It is hoped that this study's findings and recommendations can be implemented to prevent future devastating flooding occurrences within the state.The University of the Free State.https://link.springer.com/journal/41976GeologySDG-06:Clean water and sanitationSDG-11:Sustainable cities and communitiesSDG-13:Climate actionSDG-15:Life on lan

Hyperuricemia and hypertriglyceridemia: Metabolic basis for the association

Hypertriglyceridemia has been reported frequently in patients with hyperuricemia and gout. The current studies have evaluated this relationship. To examine whether hypertriglyceridemia leads to hyperuricemia, IV Intralipid was given to three gouty patients. Triglycerides increased from 169 to 700 mg/dl for three hours but caused no change in serum urate level or urine uric acid and oxypurine excretion. We next examined whether high carbohydrate intake increases serum urate and triglyceride levels. Four obese patients were placed on a 2000 kcal/d sucrose diet for seven days. The serum urate increased from 6.3 +/- 1.7 to 7.9 +/- 2.0 mg/dL. The percent uric acid clearance to creatinine clearance decreased from 5.9 +/- 1.3 to the lowest mean value of 3.7 +/- 1.2, while serum triglycerides increased from 106 +/- 33 to 252 +/- 57 mg/dL and blood lactate from 607 +/- 227 to 1167 +/- 381 [mu]mol/L. A 3000 kcal/d glucose diet in four other obese subjects produced no change in serum urate levels but increased lactate and triglyceride levels. During an isocaloric sucrose diet in two normal men, the serum urate level increased from 5.3 and 4.0 to peak values of 9.5 and 7.4 mg/dL. The percent uric acid to creatinine clearance decreased from 5.6 and 6.6 to 2.9 and 3.3. The uric acid turnover did not increase. In three gouty patients the mean serum urate increased from 8.5 +/- 1.5 to 10.6 +/- 1.4 mg/dL following an isocaloric sucrose diet. The urine uric acid excretion increased from 0.30 and 0.25 to 0.37 and 0.38 mg/mg creatinine in two patients. The percent uric acid clearance to creatinine clearance decreased from 3.8 to 2.5 in one patient. The serum triglycerides were substantially elevated during the sucrose diet in the normal subjects and the gouty patients. Our studies show that a pure sucrose diet increases both the serum urate and triglyceride levels. The mechanism of the hyperuricemia is decreased renal clearance of uric acid in the obese normal controls and the normal subjects. Increased urate production and decreased uric acid clearance accounted for the hyperuricemia in the gouty patients. The contribution of excessive sucrose ingestion to clinically associated hyperuricemia and hypertriglyceridemia remains to be elucidated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25613/1/0000161.pd

Land use change from rainforests to oil palm plantations and food gardens in Papua New Guinea: Effects on soil properties and S fractions

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