Local Rainfall Patterns Research Articles

The relationship between temperature and schizophrenia birthrates

Seasonal patterns of birthrates and birthweights have been compiled from the delivery records of 11 rural hospitals and compared with each other and with the local rainfall pattern by means of lagged regression analysis. While mean birthweight is lower in high rainfall areas, both magnitude and predictability of seasonal birthweight variations are greater in low rainfall areas. Such differences are attributed to different combinations of infection rates, dietary intake and reliability of food supply. Seasonal variations in birthrate were found to occur independently from those of birthweight. Birth seasonality was found to be prominent only in areas with holoendemic malaria and is attributed to a seasonal depression of fecundity mainly due to malaria infection.

Grass cover distribution in the central Namib— a rapid method to assess regional and local rainfall patterns of arid regions?

Grass cover distribution in the northern section of the Namib-Naukluft Park inNamibia was estimated following the rain seasons of 1989, 1990 and 1991. High cover of grass occurred particularly in the vicinity of rocky outcrops and in drainage lines. Grass distribution is related to the gradient of increasing rainfall from West to East, the soil moisture pattern influenced by runoff and the distribution of seeds in and above the soil surface. The spatial distribution of grass patches showed a certain predictability, thus providing baseline data for range management.

Seasonality of births and birthweights in Tanzania

Seasonal patterns of birthrates and birthweights have been compiled from the delivery records of 11 rural hospitals and compared with each other and with the local rainfall pattern by means of lagged regression analysis. While mean birthweight is lower in high rainfall areas, both magnitude and predictability of seasonal birthweight variations are greater in low rainfall areas. Such differences are attributed to different combinations of infection rates, dietary intake and reliability of food supply. Seasonal variations in birthrate were found to occur independently from those of birthweight. Birth seasonality was found to be prominent only in areas with holoendemic malaria and is attributed to a seasonal depression of fecundity mainly due to malaria infection.

Rainfall and birthweight distribution in rural Tanzania.

SummarySeasonal variations in birthweights over a 10-year period are compared with the local rainfall pattern in a rural area of Tanzania. Mean birthweight falls by about 60 g in the course of the rainy season. Lagged regression analysis reveals a negative impact of rainfall on birthweight after 3 months. Deviations from average rainfall show a positive correlation with birthweight after 4 months, but only in the months when rainfall is critical for food crop production. The interactions of these contrary effects are held responsible for the sudden fluctuations in mean birthweight that were observed.

Cropping‐Management Factor Evaluations for a Universal Soil‐Loss Equation

AbstractAbout 8,000 plot‐years of soil‐loss and related data assembled from 21 states were analyzed to evaluate influences of vegetal growth, crop sequence, tillage practices, fertility, and residue management on erosion of soil by rainfall. Specific‐crop data were grouped according to relatively homogeneous intervals such as the respective rough fallow, seedbed, establishment, growing crop, and residue periods. For each such period, measured soil losses under specific combinations of crop sequence and management were compared with corresponding losses from bare fallow. Not only canopy protection, but the residual effects of prior cropping and management as well, differed significantly for the respective crop‐stage periods. Soil losses for each crop‐stage period under various sequences and management levels are presented in tabular form as percentages of losses from fallow under identical rainfall. The table was designed for use with rainfall erosion index maps and monthly distribution curves computed from localized rainfall records as discussed in “A Rainfall Erosion Index for a Universal Soil‐Loss Equation” (Soil Sci. Soc. Am. Proc. 23:246–249. 1959). Combined with the erosion index and other factors comprising the soil‐loss equation, the tabulated values will help to provide valuable guides for conservation farm planning adapted to the local rainfall pattern.