The impact of skid trails on the physical properties of tropical hill forest soils

A field study was conducted in Sungai Tekam Forest Reserve of Pahang, Malaysia to evaluate the effects of skid trails on some selected soil properties. Results showed that bulk density and resistance to penetration increased while total pore space and aeration porosity decreased significantly. The available water holding capacity returned to normal after two years of exposure. This information is useful to forest and land managers who are attempting to manage soils to reduce soil compaction and erosion on skid trails and plan reforestation programmes. Research efforts should aim at reducing the alteration of some soil physical properties on skid trails by proper harvesting practices and reduction of skid trail related disturbances

Use of zeolite in maize (Zea mays) cultivation on nitrogen, potassium, and phosphorus uptake and use efficiency.

Concerns about unbalanced use of fertilizers leading to environmental pollution have been globally expressed. As a result, studies on how to use efficient methods to reduce nutrient applications at the same time increasing or maintaining crop yield, reducing nutrient losses and improving nutrient use efficiency are imperative. Nutrient loss due to leaching, volatilization and fixation upon fertilizer application to soils may be reduced through the use of slow-release fertilizers. A pot study was conducted to investigate if the use of inorganic fertilizers together with zeolite will improve nitrogen (N), phosphorus (P) and potassium (K) uptake and efficiency in maize (Zea mays) cultivation on Nyalau series (Typic Paleudalts). Maize hybrid no. 5 variety was used as test crop. Treatments evaluated were: (i) Unfertilized condition (T1), (ii) normal N, P and K application (7.4 g urea + 11.3 g Christmas Island rock phosphate (CIRP) + 3.8 g muriate of potash (MOP)) (T2), (iii) 135 g zeolite + 5.92 g urea+9.0 g CIRP + 3.0 g MOP (T3), (iv) 270 g zeolite + 4.44 g urea + 6.8 g CIRP + 2.3 g MOP (T4), (v) 405 g zeolite+3.0 g urea+4.5 g CIRP+1.5 g MOP (T5) and (vi) 540 g zeolite + 1.5 g urea + 2.3 g CIRP + 0.8 g MOP (T6). The effect of T2, T3, T4, T5 and T6 on soil N, P and Mg at harvest was not significantly different compared with T1. However, treatments with zeolite significantly increased K and Ca contents of soil compared to T1. Irrespective of treatment, dry matter production was not different. However, nutrient concentrations determined in plant tissues were clearly affected by the addition of zeolite. N, P and K uptake varied significantly but T6 significantly affected N, P and K use efficiency. The use of inorganic fertilizers mixed with zeolite remarkably increased N, P and K uptake, and their use efficiency in leaves, stem and roots. The use of zeolite could be beneficial with respect to nutrient retention in soil and their use efficiency

Survival and early growth of acacia mangium, ceiba pentandra and casuarina equisetifolia on sandy tin tailings

A field study was carried out on tin tailings to evaluate the growth performance of three timber species (Acacia mangium, Ceiba pentandra and Casuarina equisetifolia) with and without fertilization and with three species of cover crops (Centrosema pubescens, Calopogonium muconoides and Puereria phaseoloides). The experiment was carried out at Kampung Pasir, Semenyih, Ulu Langat, Selangor. NPK compound fertilizer was applied at the mle of 300 g per seedling ever)' three 'months during the first year of the study. Height and diameter were measured 23 months after planting. Soil samples were also collected for laborator), analysis. The results showed that the three timber species can grow well even without fertilizer and the growth -rates of the three species differ significantly. The fastest growth rate was recorded by Acacia mangium followed by Ceiba pentandra and Casuarina equisetifolia. The planting of cover crops slightly increased the nuttient status of the soil. Thus this experiment shows that timber species, particularly Acacia mangium, could be successfully used to rehabilitate abandoned examining land, while Ceiba pentandra and Casuarina equisetifolia could also be used, but have slower growth -rates than Acacia mangium

Utilization of activated carbon produced from Sago hampas (Metroxylon sagu) to reduce ammonia loss from urea.

Surface-applied urea contributes to NH3 loss of N through ammonia volatilization, especially in warm and humid regions. Ammonia loss has been a major problem confronting farmers because additional urea is applied to compensate for the loss which increases cost of fertilization. Activated carbon (AC) produced from Sago hampas (SH) could be capable of absorbing N in the form of NH4+ to minimize ammonia volatilization. The objective of this study was to determine if AC produced from SH could be used to retain ammonium as well as minimizing ammonia loss from urea. Activated carbon was produced from SH by using concentrated H2SO4 and (NH4)2S2O8. There were three types of AC produced using different volumes of H2SO4 (AC30, AC40 and AC50). The charred product was used as a treatment together with the raw material in order to observe the reduction of ammonia loss using closed-dynamic air flow system for 7 days. The daily loss of NH3was observed and the NH4+ and NO3- retention in the soil were determined using standard procedures. Activated carbon produced from SH had a higher CEC and it increased from AC30 to AC50. The treatments did not contribute to the reduction of ammonia loss; however, there was a significant increase in the retention of NH4+ in the soil compared to urea alone. The AC was observed to be a better absorbent than SH. AC50 was a better absorbent compared to other treatments due to high acidity and CEC. However, the treatment did not contribute to reduction of ammonia loss, but there was a significant increase of NH4 + retention in the soil

Rainfall interception, throughfall and stemflow in a secondary forest

The presence of forest or any other vegetative cover over an area of land influences the distribution pattern of rainfall. Some of the rain is intercepted and retained by the leaves and other parts of the trees and eventually lost to the atmosphere in the form of evaporation. The rain water that reaches the soil surface will arrive there by throughfall (passes directly through open spaces not covered by foliage or as drips from the vegetative parts of the tree) and also by stemflow (flows down the surface of the stem). Measurements of the amount of interception, throughfall and stemflow are therefore necessary towards understanding the role of a forest cover in the hydrological cycle in a forest ecosystem. Studies of rain interception, throughfall and stemflow have received little attention in Malaysia. Kenworthy (1970) reported one such study under primary and disturbed forests at Ulu Gombak Reserve. Teoh(1971) conducted a similar study in a rubber plantation at Sungei Buloh and Low (1972) reported the work done at Sungai Lui catchment area. This paper describes the results obtained from an investigation conducted at the Air Hitam Forest Reserve, Puchong, Selangor to find out the percent interception, throughfall and stemflow. The vegetation is typically a secondary lowland dipterocarp forest of the"Kedondong Kempas" type. An attempt was also made to relate crown area and diameter of trees at breast height (D.B.H.) to stemflow

Foliar sampling guidelines for different aged Acacia mangium plantations in Peninsular Malaysia

Foliar analysis is a useful tool for evaluating the nutritional status of a crop. There are, however, no guidelines for foliar sampling of Acacia mangium plantations in Peninsular Malaysia. This study was thus aimed to determine the best time for foliar sampling in Acacia mangium plantation. The study was conducted in Kemasul Forest Reserve, Pahang. Foliar samples were collected monthly from Acacia mangium stands of five different ages over a period of one year. The results show that foliar sampling in Acacia mangium stands should be performed as follows: for one-year-old stand in January-March and June-July; for two-year-old stand in December-January and June-July; for three-year-old stand in June-July; for four-year-old stand in February-March and June-July; for six-year-old stand in February-March. In general, July is the best time for foliar sampling of one- to four-year-old stands whereas February-March would be the best time for six-year-old stands. The results are based on the fact that foliar nutrients are generally constant over these periods

Predicting N,P,K and organic carbon depletion in soils using MPSIAC model at the Merek catchment, Iran.

Land degradation is the loss in the productivity of land resources due to many factors, especially soil erosion. Nutrient depletion and soil organic carbon (SOC) loss are the main impacts of erosion which not only cause declining crop yield, but also induce off-site impacts, such as eutrophication and greenhouse gas (GHG) emission. The main objective of this study was to estimate the depletion of N, P, K and SOC due to soil erosion prevailing in the three agro-ecological zones within the Merek catchment, Iran. The erosion rate and eroded plant nutrients (N, P and K) as well as SOC were estimated using MPSIAC model. The results showed that the most important factor affecting land degradation in the Merek catchment is inter-rill erosion, covering an area of about 20%, which in turn is promoted by deforestation and overgrazing. The erosion rate in the agriculture area, rangeland and forest is 14.47, 16.60 and 18.57 t ha− 1 yr− 1, respectively. The respective predicted annual N depletion by erosion is 23.5, 26.6 and 32.8 kg ha− 1 yr− 1 in agriculture area, rangeland and forest zone, while that of P is 0.230 and 0.290 and 0.220 kg ha− 1 yr− 1. The depletion of K in agriculture area is 7.01, rangeland is 6.25 and forest is 6.36 kg ha− 1 yr− 1. The highest loss in SOC is in the forest with a value of 414 kg ha− 1 yr− 1 while the lowest is in the agriculture area with a value of 213 kg ha− 1 yr− 1. The high loss of SOC in the forest zone is due to serious soil erosion, which is accelerated by sloping land. It is concluded that the MPSIAC model used in this study is able to satisfactorily predict soil erosion rate and the loss of N, P, K and SOC at the catchment scale in the semi-arid region of Iran

Effect of amending urea with humic acids and acid sulphate on biomass production of Masmadu (Zea mays L.) and selected soil chemical properties.

Excessive use of fertilizers especially nitrogenous fertilizers with low management in relation to food safety and environmental pollution has in recent times become a subject of concern. This greenhouse study compared the effect of three different urea-humic acid-acid sulphate soil mixtures on maize biomass production, soil pH, ammonium and nitrate contents, and urea use efficiency compared with urea-N without additives (urea alone). Humic acid (HA), acid sulfate soil and soil used in the greenhouse study were analyzed for selected soil physio-chemical properties. The fertilizer mixtures and ammonia loss determination were carried out using standard methods. The treatments were evaluated in a completely randomized block design with 3 replications. The data obtained at the end of the study on biomass production, soil pH, exchangeable ammonium and available nitrate were analyzed using analysis of variance and the means were compared using Duncan’s test using statistical analysis systerm (SAS) version 9.2. The soil used to test treatments was a sandy clay loam Typic Tualemkuts (Nyalau Series). Urea amended with different levels of HA alone significantly improved soil exchangeable ammonium compared to urea alone. All the mixtures significantly improved soil pH compared with urea alone. However, all the mixtures did not significantly affect biomass production and content of available nitrate compared with urea alone. Amending urea with HA and acid sulphate soil did not significantly affect biomass production of Masmadu (test crop) but it significantly improved soil pH and retention of exchangeable ammonium

Ammonia loss reduction, exchangeable ammonium and available nitrate retention in soil treated with urea mixed with humic acid and acid sulphate soil.

Exchangeable ammonium (NH4 + ) could be recovered in soil by the application of humic acid (HA) and acid sulphate soil. The ability of humic acids to retain NH4 + has been demonstrated in our previous study. In that study, the effect of both acids on soil exchangeable NH4 + , dry matter production and available nitrate (NO3 - ) was investigated. This laboratory study compared the effect of enhancing urea mixtures with HA and acid sulphate soil on NH3 loss, and soil ammonium and nitrate contents, with loss from surface applied urea and to study the appropriate application ratio. HA, acid sulphate soil, and the mineral soil Nyalau Series (Typic paleudults) used in the incubation studies were characterized prior to the experiment. A closed-dynamic air flow system was used to evaluate the treatments effects with 3 replications in a completely randomized design (CRD). The data obtained were analyzed using Duncan’s test with Statistical Analysis Syetem (SAS) version 9.2. Application of urea amended with various amounts of HA and acid sulphate soil and urea with HA alone did not minimize ammonia loss especially at higher amounts (T5, T9 and T10). The application of urea amended with acid sulphate soil however did not reduce ammonia loss even though it delayed the ammonia loss at higher amounts (T13 and T14). The application of acid sulphate-urea-HA mixture (T5) and urea-HA mixtures (T9 and T10) reduced NH3 loss in acid soil by improving ammonium retention. This study can contribute to improving urea N use efficiency as well as reducing environmental pollution in agriculture and forestry