Mohammad Sujauddin

Effects of phosphorus and potassium addition on growth and nodulation of Dalbergia sissoo in the nursery

A study was conducted to test the influence of different inorganic fertilizers (phosphorous and potassium) on the nodulation and growth of Dalbergia sissoo grown in the nursery. Before seeds sowing, different combinations of P, K fertilizers were incorporated with the nutrient-deficient natural forest soils, and then amended with cowdung (soil: cowdung = 3:1). Nodulation status (nodule number, shape, fresh weight, dry weight and color) in the roots and the plant growth parameters (length of shoot and root, collar diameter, fresh and dry weight of shoot and root) were recorded 60 days after seeds sowing. Nodulation status and growth of the plants varied significantly (P<0.05) in the soils amended with fertilizers in comparison to the control. The highest nodule number (62), fresh (0.50 g) and dry (0.07 g) weights were recorded with the dose of PK at the rate of 160 kg/hm2. Nodule shape and color also varied widely in different treatments. In case of plant growth parameters, shoot and root length, collar diameter, fresh and dry weight of the plants took on a significant difference (P<0.05) among various combination of fertilizers. From the study, it is revealed that PK at the rate of 160 kg/hm2 fertilizer with soil and cowdung mixture (soil: cowdung = 3:1) is recommended for optimum growth and nodule formation of D. sissoo in degraded soils at a nursery level.

Effects of sludge on germination and initial growth performance of Leucaena leucocephala seedlings in the nursery

A study was carried out to determine the influence of different types of sludges (municipal, industrial and residential) on field germination, growth and nodulation of L. leucocephala seedlings in the nursery. Before sowing of seeds, different combinations of sludges were incorporated with the nutrient deficient natural forest soils. Field germination, nodulation status and physical growth parameters of seedlings (shoot and root length, vigor index, collar diameter, leaf number, fresh and dry weight of shoot and root and total dry biomass increment) were recorded after three and six months of seed sowing. Field germination, nodulation status and growth parameters were varied significantly in the soil amended with sludges in comparison to control. The highest number of nodule was recorded from soil amended with residential sludge (1:1) and highest fresh and dry nodule weight was also found from the same combination in both three and six month old seedlings. In case of growth parameters, the highest growth was recorded from soil and residential sludge (1:1) combination compared to control. From the study, it can be recommended that soil amended with residential sludge (1:1) provide better field germination, growth and nodule formation of L. leucocephala in degraded soil.

Current status of municipal solid waste management system in Chittagong, Bangladesh

This paper presents an overview of MSW management in Chittagong, the second largest city of Bangladesh. The total MSW generation in Chittagong increased steadily from 538 tons/day in 1999 to 984 tons/day in 2005 and 1890 tons/ day in 2009. MSW collection coverage of Chittagong City Corporation increased from 45% in 1999 to 64% in 2008 and almost 70% in 2009. Approximately 72% (952 tons) of the total daily collected MSW in 2009 were disposed of as unsanitary landfilling and 27.62% (365 tons) as open dumping; while, only 0.16% (2,116 kg) were managed through systematic recovery and recycling.

Effects of coastal afforestation on some soil properties in Lakshmipur coast of Bangladesh

Coastal zones comprising important intertidal tropical and subtropical ecosystems are characterized by high productivity, diversity and unique zonation of various plant and animal communities. The comparison of some selected physicochemical soil properties viz. texture, particle density, moisture content, pH, organic carbon and total nitrogen between planted site (Telir char) and barren site (Boyar char) has been investigated at surface (0–10 cm) and subsurface (10–45 cm) soil across three different land strips viz. inland, middle part and sea side in Lakshmipur coast of Bangladesh. Sand particles in the soil were lower in planted site than barren site. The reverse trend was found in case of both silt and clay percentage. Coastal afforestation had a significant effect on soil binding process since a common trend of increment in soil particle density was noticed. Maximum increment (20.43% to 23.30%) in soil moisture content was recorded in surface soil across the seaside while at subsurface soil both across the middle part (19.53% to 22.30%) and sea side (20.19% to 22.96%). Moreover, the highest reduction in soil pH was recorded at surface soil (7.27 to 6.60) across the sea side and subsurface soil (7.16 to 6.67) in inland due to the influence of coastal plantation. Across all the land strips and the soil depths studied, soil organic carbon was higher in planted site than in barren site with only exception at subsurface soil in the middle part (0.50% in both sites). Total soil nitrogen in the study area was increased at both depths due to forestation with the highest increment in the inland at both surface and subsurface soil.

Exposure of educational institutions to traffic-induced noise at Chittagong City, Bangladesh

The amplitude and intensity of traffic-induced noise at the environmental setup of the educational institutions in Chittagong City, Bangladesh were investigated. Average maximum and minimum sound levels in the study area ranged from 65.46 to 82.24 dB and 60.63 to 70.89 dB, respectively. Noise at all the studied educational institutions exceeded the safe limit (45 dB) as prescribed by the Department of Environment, Bangladesh and World Health Organization. Sound levels showed a significant (P = 0.000) declining trend with increase in the distance from the source of noise. Among the noise-induced physical health problems, headache (69%) and among the mental health problems, lack of concentration in study (78%) was expressed by the maximum number of students. The findings of the study can be considered as baseline data for the decision makers in formulating policies and guidelines regarding the control of noise pollution in the context of educational institutions.

Coastal afforestation effects on soil properties at Hatiya in Bangladesh

An exploratory study was conducted in the coastal plantation (12- and 17-year-old Sonneratia apetala) of Char Alim and Char Piya and their adjacent barren lands at Char Rehania and Char Nurul Islam in Hatiya under Noakhali district in Bangladesh to determine afforestation effects on soil properties. At soil depths of 0–10, 10–30 and 30–40 cm across three different land strips viz. inland, middle and sea side in 12- and 17-year-old keora (Sonneratia apetala) plantations, soil moisture, particle density, organic matter and C, total N, pH, available P, K, Na, Ca and Mg were significantly (p≤0.05, p≤0.01, p≤0.001) higher, and soil salinity significantly (p≤0.001) lower than that in their adjacent barren lands. Soil moisture, particle density, organic matter and C, total N, pH, soil salinity, available P, K, Na, Ca and Mg of surface soil in Char Alim plantation at inland were 31.09%, 2.24 g·cm−3, 2.41%, 4.14%, 0.58%, 7.07, 0.09 dS·cm−1, 28.06 mg·L−1, 0.50, mg·L−1 11.5 mg·L−1, 3.30 mg·L−1 and 2.7 mmol·kg−1, respectively. Their corresponding values for the same depth and land position at adjacent Char Rehania barren land were 16.69%, 1.25g·cm−3, 0.43%, 0.74%, 0.25%, 6.57, 0.13 dS·cm−1, 13.07mg·L−1, 0.30 mg·L−1, 1.4 mg·L−1, 0.30 mmol·kg−1 and 0.50 mg·L−1, respectively. Soil moisture, particle density, organic matter and C, total N, pH, available P, K and Ca decreased, and soil salinity, available Na and Mg increased from inland towards sea side in the plantations. Although soil texture did not differ in most soil depths between plantation and adjacent barren land, proportion of sand particle was significantly (p≤.01) lower and silt particle significantly (p≤0.001) in the plantations higher than that in their adjacent barren lands. In the study, evaluation of all the parameters was also done for the other pair of lands.