Enhancing food security in semi-arid eastern Indonesia through permanent raised-bed cropping: a review

1999 ◽  
Vol 39 (8) ◽  
pp. 1035 ◽  
Author(s):  
D. E. Van Cooten ◽  
A. K. Borrell
Keyword(s):  
Water Supply ◽  
Food Production ◽  
Crop Production ◽  
Ground Cover ◽  
Dry Season ◽  
Wet Season ◽  
Additional Food ◽  
Eastern Indonesia ◽  
Raised Bed ◽  
Semi Arid

Summary. Much of south-eastern Indonesia is mountainous and characterised by a semi-arid tropical environment. Soil erosion is a significant environmental problem facing the region, affecting both productivity of the land and water quality. The challenge for the region is to secure year-round food production in such a fragile environment. More than 90% of rain falls in a distinct wet season between November and April. Therefore, cropping in this region is dependent on matching crop growth with water supply. In particular, crop production depends on the efficient use of rainfall during the wet season, including avoidance of waterlogging, and efficient use of stored soil water during the dry season. This paper summarises the results of a series of experiments undertaken in West Timor, Indonesia, between 1993 and 1999 aimed at developing a raised-bed cropping system. The objective of these studies was to better utilise the more fertile alluvial soils that are often susceptible to waterlogging during the wet season, allowing a range of crops to be grown in addition to rice. Raised beds of height 0.2 m and width 1.5 m were constructed either manually or with an 8.5 hp two-wheeled hand tractor. A range of crops including soybeans, sorghum, maize, pigeon pea, yam bean and cassava were successfully grown on raised beds in the wet season in addition to rice, indicating that raised-bed technology overcomes the constraints of waterlogging in the wet season. Soybeans grew particularly well on raised beds, with December-sown crops producing almost twice the yield of January-sown crops (2.6 v. 1.4 t/ha). For rice and soybeans, early sown crops were better able to match growth with water supply, thereby avoiding end-of-season drought. Early sowing and harvesting of wet season crops enables a drought-resistant crop such as sorghum to be planted in lateMarch or early April, utilising the stored soil moisture for grain production and also maintaining ground cover in the dry season. It is argued that cropping systems based on permanent raised beds can reduce erosion in 2 ways. First, raised beds are a permanent structure and, with the inter-cropping and relay-cropping proposed, crops can provide all-year ground cover in lowland areas. Second, if sufficient food and cash crops are grown on raised beds to meet the basic needs of subsistence farmers, then upland cropping on steep slopes can be replaced by a variety of tree species, providing additional food, fodder, firewood and medicines. Together, these strategies have the capacity to enhance food production and security in the semi-arid areas of eastern Indonesia.

scholarly journals Epidemiology of gastrointestinal helminths infections in Dorper sheep in a semi-arid area of Kenya

2004 ◽  
Vol 71 (3) ◽  
Author(s):  
C.J. Ng'ang'a ◽  
N. Maingi ◽  
W.K. Munyua ◽  
P.W.N. Kanyari
Keyword(s):  
Age Groups ◽  
Dry Season ◽  
Arid Area ◽  
Wet Season ◽  
Weather Factors ◽  
Gastrointestinal Helminths ◽  
Faecal Samples ◽  
Dorper Sheep ◽  
Short Rains ◽  
Semi Arid

A survey on the prevalence and intensity of infection with gastrointestinal helminths of Dorper sheep in relation to age and weather factors was carried out on a ranch in Kajiado district, a semi-arid area of Kenya for a period of 13 months (May 1999 to May 2000). Faecal samples from lambs (3 months to 1 year), yearlings (1-2 years) and adult breeding ewes (2-4 years) were examined for helminth egg output and helminth genus composition at 3-week intervals. The results indicated that the prevalence of strongyle and tapeworms infections were highest for lambs, followed by the adult breeding ewes and then for the yearlings. In all age groups the proportions of infected animals were higher during the wet season than in the dry season for both nematodes and tapeworms. The mean strongyle egg counts were higher during the dry season for lambs, but were higher during the wet season for the other age groups. Mixed strongyle infections were detected, with Trichostrongylus (55 %), Haemonchus (28 %), Cooperia (10.5 %) and Oesophagostomum (6.5 %) being the most frequently encountered genera throughout the study period. The trends in strongyle faecal egg counts indicated the occurrence of hypobiosis, with resumption of development towards the end of the dry season and at the onset of the short rains in October and November. Self-cure was also observed in September and November in all age groups, although less frequently in lactating ewes. The prevalence and intensities of infection with gastrointestinal helminths in this area appeared to be influenced by the age of the host and weather factors.

scholarly journals ALGUNOS ASPECTOS SOBRE LA TEMPERATURA DE HOJAS PERTENECIENTES A PLANTAS DE LA REGIÓN XEROFÍTICA DE SANTA MARTA (COLOMBIA)

2016 ◽  
Vol 5 ◽  
Author(s):  
Reinhard Schnetter
Keyword(s):  
Water Supply ◽  
Plant Species ◽  
High Temperatures ◽  
Dry Season ◽  
Wet Season ◽  
Favorable Conditions ◽  
Very High

Leaf temperatures of several plant species of the xerophytic vegetation near Santa Marta (Colombia) were studied during the dry and the wet season. The leaves of species growing in a cactus thorn scrub reached very high temperatures, especially in the dry season, while leaf temperatures of plants in the area of a disappeared semi-deciduous seasonal forest were lower because of more favorable conditions of water supply and microclimate.

Seasonal evapotranspiration of irrigated cotton in a low-latitude environment

1967 ◽  
Vol 18 (2) ◽  
pp. 259 ◽  
Author(s):  
WR Stern
Keyword(s):  
Meteorological Factors ◽  
Ground Cover ◽  
Dry Season ◽  
Potential Evaporation ◽  
Crop Water ◽  
Wet Season ◽  
Low Latitude ◽  
Area Index ◽  
The Mean ◽  
Dominant Influence

Evapotranspiration (Et) from irrigated cotton was determined on a sequence of plantings covering a whole year. Averaged over the year, evapotranspiration directly after irrigation (Et1) was greater than the Penman estimate of potential evaporation (E) but less than the evaporation from a standard Australian tank (Etank). The mean annual ratios were 1.2 for Et1/E and 0.9 for Et1/Etank. The rate of evapotranspiration was a function of soil moisture, declining rapidly as the available moisture fell below 60 %. Because of the high variability in the estimates of evapotranspiration it was not possible to evaluate precisely the influence of growth stage on evapotranspiration. Although there was evidence that evapotranspiration varied with the stage of growth, meteorological factors were a dominant influence because of the high watering regime. Overall, a crop planted in the wet season used little more water than a crop planted in the dry season. After the maximum leaf area index (LAI) had been reached, evapotranspiration in the wet season crop declined more rapidly and fell to a lower value than evapotranspiration during the corresponding period in the dry season crop. Water was used more efficiently by the wet season crop than by the dry season crop. The conclusion was reached that in this environment advection of energy persisted for most of the year, and that during periods of rapid height increases, particularly when ground cover was incomplete, crop surface roughness enhanced evapotranspiration. The possible interactions of some of the factors influencing evapotranspiration in a crop in the field are discussed.

Growth Strategies of Eucalyptus camaldulensis Dehnh. At Three Sites in Northern Australia

1994 ◽  
Vol 21 (5) ◽  
pp. 653 ◽  
Author(s):  
A Gibson ◽  
EP Bachelard ◽  
KT Hubick
Keyword(s):  
Gas Exchange ◽  
Shoot Growth ◽  
Eucalyptus Camaldulensis ◽  
Dry Season ◽  
Growth Strategies ◽  
Wet Season ◽  
Wind Speeds ◽  
The North ◽  
Air Temperatures ◽  
Semi Arid

The morphology and physiology of trees of Eucalyptus camaldulensis growing in the field at two monsoonal and one semi-arid location were compared. In the wet season, shoot growth at the monsoonal locations was similar and larger than that at the semi-arid location. In the dry season, new shoot growth at the more humid monsoonal location (Petford) was similar to growth in the wet season while at the less humid (Katherine) and the semi-arid (Tennant Creek) locations, shoot growth was foreshortened and the leaves had larger dry weights per unit area. In the summer wet season, leaves on both the north and south sides of the trees were maintained at or below (by up to 5�C) air temperatures throughout the day except for north facing leaves at Petford which were consistently above (by up to 3�C) air temperatures. Midday gas exchange in the dry season at both monsoonal localities was restricted to trees at the water's edge, whereas most trees, including those at drier sites, at the semi-arid location exhibited significant rates of gas exchange. The results, which are discussed in relation to environmental variables (vapour pressure deficits, wind speeds) to which the trees are exposed, and to previous results obtained in the glasshouse, indicate that the differences in shoot growth and physiology are adaptations to the environment in which the trees have evolved.

Remote sensing of fire regimes in semi-arid Nusa Tenggara Timur, eastern Indonesia: current patterns, future prospects

2006 ◽  
Vol 15 (3) ◽  
pp. 307 ◽  
Author(s):  
Rohan Fisher ◽  
Wilfrida E. Bobanuba ◽  
Agus Rawambaku ◽  
Greg J. E. Hill ◽  
Jeremy Russell-Smith
Keyword(s):  
Remote Sensing ◽  
Prescribed Burning ◽  
Landsat Imagery ◽  
Great Majority ◽  
Fire Regimes ◽  
Dry Season ◽  
Hotspot Detection ◽  
Fire Policy ◽  
Eastern Indonesia ◽  
Semi Arid

Substantial areas of eastern Indonesia are semi-arid (with a pronounced dry season extending from April to November) with extensive areas of uncultivated vegetation dominated by savanna grasslands and woodlands. These are highly fire-prone, despite high population densities reliant on intensive subsistence agriculture and an official national fire policy that prohibits all burning. To date, no regional studies have been undertaken that reliably assess the seasonal extent and patterning of prescribed burning and wildfire. Focusing on two case studies in east Sumba (7000 km2) and central Flores (3000 km2) in the eastern Indonesian province of Nusa Tenggara Timur, the present paper addresses: (1) the efficacy of applying standard remote sensing and geographic information system tools as developed for monitoring fire patterns in savanna landscapes of adjacent northern Australia, for (2) describing the seasonal patterning of burning at village and broader regional scales in 2003 and 2004. Despite recurring cloudiness, which significantly affected daily fire detection of ‘hotspots’ from Advanced Very High Resolution Radiometer and Moderate Resolution Imaging Spectroradiometer sensors, fire mapping from Landsat imagery was undertaken successfully to reveal: (1) fires burnt an annual average of 29% of eastern Sumba (comprising mostly grassland savanna), and 11% of central Flores (with large forested areas); (2) most fire extent occurred in savanna grassland areas, and significantly also in cultivated lands and small remnant patches of forest; (3) most fire activity occurred under harsh, late dry season conditions; and (4) while the great majority of individual fires were less than 5 ha, some late dry season fires were hundreds of hectares in extent. The potential routine application of different image sensors for fire mapping and hotspot detection is considered in discussion.

scholarly journals Seasonal study on soil salinity and its relation to other properties at Satkhira district in Bangladesh

2019 ◽  
Vol 30 (2) ◽  
pp. 157-164
Author(s):  
U Kumar ◽  
JR Mitra ◽  
MY Mia
Keyword(s):  
Soil Salinity ◽  
Crop Production ◽  
Agricultural Land ◽  
Chemical Properties ◽  
Dry Season ◽  
P Value ◽  
Optimum Level ◽  
Wet Season ◽  
Total N ◽  
Properties Of Soil

The study was conducted at Shyamnagar and Talaupazila of Satkhira district in Bangladesh to know about the soil salinity and its relation to other properties of soil in both dry and wet season and comparison the present status of soil between two upazilas. Electrical Conductivity (EC) value of the study area showed that yield of many crops can be restricted in dry season due to salinity. Mean EC was slightly saline (5.93 dsm-1) in dry season and non- saline (0.61 dsm-1) in wet season. Ranges of pH were slightly acidic to slightly alkaline (6.2 to 7.5) in dry season and slightly acidic to neutral (5.7 to 6.9) in wet season. pH values indicate it was suitable for crop production. Mean Organic Matter (OM) status was low in both seasons (1.5 % in dry season and 1.6 % in wet season). Mean total N status was very low (0.08 %) in dry season and low (0.10 %) in wet season. Mean status of P in the study areas was low (8.08 µgg-1 soil) in dry season and very low (4.98 µgg-1 soil) in wet season. Mean status of K, Ca, Mg, S and Zn were very high in both season of study area and this was may be due to excessive fertilizer use and inherent properties of soil in the agricultural land. Mean status of B was high in Tala in both season and in Shyamnagar was high in dry season and optimum in wet season. To test the significance of the pair of parameters p-value has been measured. Pearson’s correlations among the different parameters were done to identify the highly correlated and interrelated soil quality parameters. EC showed significant and positive correlation with Potassium, Sulphur and Zinc in dry season. Although chemical properties of soil at Shyamnagar and Talaupazila was not found similar and optimum level but it was found that the chemical properties of soil of wet season more suitable than the dry season because of soil salinity. Progressive Agriculture 30 (2): 157-164, 2019

scholarly journals General procedure to initialize the cyclic soil water balance by the Thornthwaite and Mather method

2010 ◽  
Vol 67 (1) ◽  
pp. 87-95 ◽  
Author(s):  
Durval Dourado-Neto ◽  
Quirijn de Jong van Lier ◽  
Klaas Metselaar ◽  
Klaus Reichardt ◽  
Donald R. Nielsen
Keyword(s):  
Water Balance ◽  
Soil Water ◽  
General Procedure ◽  
Water Storage ◽  
Dry Season ◽  
Soil Water Balance ◽  
Soil Water Storage ◽  
Wet Season ◽  
Water Balance Components ◽  
Semi Arid

The original Thornthwaite and Mather method, proposed in 1955 to calculate a climatic monthly cyclic soil water balance, is frequently used as an iterative procedure due to its low input requirements and coherent estimates of water balance components. Using long term data sets to establish a characteristic water balance of a location, the initial soil water storage is generally assumed to be at field capacity at the end of the last month of the wet season, unless the climate is (semi-) arid when the soil water storage is lower than the soil water holding capacity. To close the water balance, several iterations might be necessary, which can be troublesome in many situations. For (semi-) arid climates with one dry season, Mendonça derived in 1958 an equation to quantify the soil water storage monthly at the end of the last month of the wet season, which avoids iteration procedures and closes the balance in one calculation. The cyclic daily water balance application is needed to obtain more accurate water balance output estimates. In this note, an equation to express the water storage for the case of the occurrence of more than one dry season per year is presented as a generalization of Mendonça's equation, also avoiding iteration procedures.

scholarly journals Relations between Interannual Variability of Regional-Scale Indonesian Precipitation and Large-Scale Climate Modes during 1960–2007

2020 ◽  
Vol 33 (12) ◽  
pp. 5271-5291 ◽  
Author(s):  
Givo Alsepan ◽  
Shoshiro Minobe
Keyword(s):  
El Niño ◽  
Large Scale ◽  
El Nino ◽  
Regional Scale ◽  
Moisture Flux ◽  
Dry Season ◽  
Wet Season ◽  
Climate Modes ◽  
Eastern Indonesia ◽  
El Niño Modoki

AbstractRegional-scale precipitation responses over Indonesia to major climate modes in the tropical Indo–Pacific Oceans, namely canonical El Niño, El Niño Modoki, and the Indian Ocean dipole (IOD), and how the responses are related to large-scale moisture convergences are investigated. The precipitation responses, analyzed using a high-spatial-resolution (0.5° × 0.5°) terrestrial precipitation dataset for the period 1960–2007, exhibit differences between the dry (July–September) and wet (November–April) seasons. Canonical El Niño strongly reduces precipitation in central to eastern Indonesia from the dry season to the early wet season and northern Indonesia in the wet season. El Niño Modoki also reduces precipitation in central to eastern Indonesia during the dry season, but conversely increases precipitation in western Indonesia in the wet season. Moisture flux analysis indicates that corresponding to the dry (wet) season precipitation reduction due to the canonical El Niño and El Niño Modoki anomalous divergence occurs around the southern (northern) edge of the convergence zone when one of the two edges is located near the equator (10°S–15°N) associated with their seasonal migration. This largely explains the seasonality and regionality of precipitation responses to canonical El Niño and El Niño Modoki. IOD reduces precipitation in southwestern Indonesia in the dry season, associated with anomalous moisture flux divergence. The seasonality of precipitation response to IOD is likely to be controlled by the seasonality of local sea surface temperature anomalies in the eastern pole of the IOD.

scholarly journals An integrodifference model for vegetation patterns in semi-arid environments with seasonality

2020 ◽  
Vol 81 (3) ◽  
pp. 875-904
Author(s):  
Lukas Eigentler ◽  
Jonathan A. Sherratt
Keyword(s):  
Seed Dispersal ◽  
Spatial Patterns ◽  
Dry Season ◽  
Vegetation Patterns ◽  
Arid Environments ◽  
Wet Season ◽  
Temporal Separation ◽  
Pde Model ◽  
Dispersal Events ◽  
Semi Arid

Abstract Vegetation patterns are a characteristic feature of semi-deserts occurring on all continents except Antarctica. In some semi-arid regions, the climate is characterised by seasonality, which yields a synchronisation of seed dispersal with the dry season or the beginning of the wet season. We reformulate the Klausmeier model, a reaction–advection–diffusion system that describes the plant–water dynamics in semi-arid environments, as an integrodifference model to account for the temporal separation of plant growth processes during the wet season and seed dispersal processes during the dry season. The model further accounts for nonlocal processes involved in the dispersal of seeds. Our analysis focusses on the onset of spatial patterns. The Klausmeier partial differential equations (PDE) model is linked to the integrodifference model in an appropriate limit, which yields a control parameter for the temporal separation of seed dispersal events. We find that the conditions for pattern onset in the integrodifference model are equivalent to those for the continuous PDE model and hence independent of the time between seed dispersal events. We thus conclude that in the context of seed dispersal, a PDE model provides a sufficiently accurate description, even if the environment is seasonal. This emphasises the validity of results that have previously been obtained for the PDE model. Further, we numerically investigate the effects of changes to seed dispersal behaviour on the onset of patterns. We find that long-range seed dispersal inhibits the formation of spatial patterns and that the seed dispersal kernel’s decay at infinity is a significant regulator of patterning.

scholarly journals Vegetation indices as proxies for spatio-temporal variations in water availability in the Rio Santa valley (Peruvian Andes)

2021 ◽  
Author(s):  
Lorenz Hänchen ◽  
Cornelia Klein ◽  
Fabien Maussion ◽  
Wolfgang Gurgiser ◽  
Pierluigi Calanca ◽  
...  
Keyword(s):  
Water Availability ◽  
Rainy Season ◽  
Vegetation Indices ◽  
Growing Season ◽  
Dry Season ◽  
Season Length ◽  
Wet Season ◽  
Peruvian Andes ◽  
Spatio Temporal ◽  
Semi Arid

Abstract. In the semi-arid Peruvian Andes, the growing season is mostly determined by the timing of the onset and retreat of the wet season, to which annual crop yields are highly sensitive. Recently, local farmers in the Rio Santa basin (RSB) reported decreasing predictability of the onset of the rainy season and further challenges related to changes in rainfall characteristics. Previous studies based on time series of local rain gauges however, did not find any significant changes in either the timing or intensity of the wet season. Both in-situ and satellite rainfall data for the region lack the necessary spatial resolution to capture the highly variable rainfall distribution typical for complex terrain, and are often questionable in terms of quality and temporal consistency. To date, there remains considerable uncertainty in the RSB regarding hydrological changes over the last decades. In this study, we overcome this limitation by exploiting satellite-derived information on vegetation greenness to reveal a robust and highly resolved picture of recent changes in rainfall and vegetation phenology across the region: As the semi-arid climate causes water availability (i.e. precipitation) to be the key limiting factor for plant growth, patterns of precipitation occurrence and the seasonality of vegetation indices (VIs) are tightly coupled. Therefore, VIs can serve as an integrated proxy of rainfall. By combining MODIS Aqua and Terra VIs for 2000–2020 and several datasets of precipitation, we explore recent spatio-temporal changes in vegetation and water availability. Furthermore, we examine their links to El Niño Southern Oscillation (ENSO). While different rainfall datasets tend to be incoherent in the period of observation, we find significant greening over the majority of the RSB domain in VI data, particularly pronounced during the dry season (Austral winter). This indicates an overall increase of plant available water over time. The rainy season onset and consequently the start of the growing season (SOS) exhibits high inter-annual variability and dominates the growing season length (LOS). The end of the growing season (EOS) is significantly delayed in the analysis which matches the observed dry-season greening. By partitioning the results into periods of three stages of ENSO (neutral, Niño, Niña), we find an earlier SOS and an overall increased season length in years associated with El Niño. However, the appearance of Niño/Niña events during the analysed period cannot explain the observed greening and delayed EOS. While our study could not corroborate anecdotal evidence for recent changes in the SOS, we confirm that the SOS is highly variable and conclude that rainfed farming in the RSB would profit from future efforts being directed towards improving medium-range forecasts of the rainy season onset.

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