Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

A Comparative Study on the Effects of Treated and Untreated Tannery Wastes on Plant Growth

Sohana Shabnam
Department of Soil, Water and Environment, University of Dhaka, Dhaka-1000

S. M. Imamul Huq
Bangladesh-Australia Centre for Environmental Research (BACER-DU), Department of Soil, Water and Environment, University of Dhaka, Dhaka-1000

Shafiqur Rahman
Department of Soil, Water and Environment, University of Dhaka, Dhaka-1000

Abstract/ Executive Summary:

A net house pot experiment was conducted to compare the effect of untreated and treated wastes and effluents on soil properties and plant growth. It was observed that the untreated wastes and effluents from Hazaribagh tannery area contain comparatively higher amounts of N, S, P, Na, K and the heavy metals Cd, Cu, Pb and Zn compared to the ones collected from the Nayarhat tannery area where effluent treatment plant is in operation. The effluent and wastes from the latter industry were found cleaner and harmless to the environment. The pot experiment with plants grown on soil treated with different types and doses of wastes and effluents showed that although the plant growth might not be affected by untreated wastes and effluents as these provide huge nutritional elements but the plants accumulate greater amount of heavy metals which might be a threat to the consumer.

Keywords: Tannery waste, Plant growth, Heavy metals

Location: The net-house of the Department of Soil, Water and Environment, University of Dhaka

Start Date:

End Date:

Program Area: Risk Management in Agriculture

Commodity: Contamination of soil

Objectives:

To check the heavy metal contamination in the growing plants receiving effluents from the two different types of sources.

Methodology:

A pot experiment was conducted in the net-house of the Department of Soil, Water and Environment, University of Dhaka. The solid wastes collected from the different tannery areas were processed for subsequent experiments and for physico-chemical analysis in the laboratory. Three sampling sites were selected for collecting the samples for the experiments. i) Dhamrai in Dhaka district- unpolluted soil was collected from here to use in the pot experiment; the soils belong to the Dhamrai series. The soils were collected at 0-15 cm depth. No industrial establishments were located near the site. ii) Hazaribagh Tannery Area- the largest and the worst polluted industrial area of Dhaka City situated on the bank of the Buriganga River; and iii) Nayarhat tannery industrial area- with wastes treatment facilities, located at Dhamrai, on the bank of the Bongshi River. Solid wastes and effluents were collected from the source points of the two industrial areas- X tannery (representing the untreated effluent and waste) at Hazaribagh, and Y tannery (representing the treated effluent and waste) at Nayarhat. Solid wastes and effluents were taken in polythene bags and plastic containers respectively. The samples were preserved at normal temperature in laboratory. A portion of the crushed soils was passed through a 2.0 mm sieve. The sieved soils were then preserved in plastic bags and labeled properly. These were later used for various chemical analysis. The pots were arranged in a completely randomized way and 39 pots were used. The experiment was designed as follows: for the Hazaribagh site: plant type (1) x soil type (1) x solid waste type (2) x treatment (3) x replication (3) and for the Nayarhat site plant (1) x soil type (1) x effluent type (2) x treatment (3) x replication (3). Thus each experiment with polluted soils required 18 pots; and 3 pots contained the unpolluted soil used as absolute control. Six kgs of air-dried soil samples were taken in each of the earthen pots. Wastes were mixed with the soil at a rate of 2.5 t ha^-1 , 5.0 t ha^-1 and 10.0 t ha^-1 ; and effluents were added with the soil at a rate of 100 ml kg^-1 , 200 ml kg^-1 and 300 ml kg^-1. Fifteen seeds of the plant were sown in each of 39 pots. After one week of germination, three plants were uprooted and rests of the healthy seedlings were allowed to grow. The moisture content of the soil was maintained between 50 and 80% field capacity throughout the growing period. Tap water was used for this purpose. The plants were harvested periodically after 15, 30 and 45 days of germination. Harvested plant samples were washed first with tap water and then with distilled water thrice to remove the soil particles and other extraneous materials. The root and shoot parts were separated with knife and processed separately.Moisture contents of air-dried samples were determined. The particle size analysis of soils were conducted by hydrometer method as described and the textural classes were determined by Marshall's Triangular Coordinates as devised by the United States Department of agriculture. Organic carbon, total nitrogen, contents of P0₄-P and S0₄-S Na, K, Ca,Mg, total Fe, Mn, Zn, Pb, Cu and Cd were determined following the methods as described for soil or waste samples. The concentrations of cr, HC0₃- and C03². in water and effluent samples were determined titrimetrically. Plant nitrogen was determined by alkali distillation of the Keldahl's digest. After wet oxidation with ternary acid mixture (HN0₃: H₂ S0₄: HC10₄= 5: 1: 2) as described by Imam and Didar (2005), the total contents of P, S, Na, K , Fe, Mn, Zn, Pb, Cu and Cd were determined by using the procedures mentioned for soil. Microsoft Excel and MINITAB (version 13) were used for data manipulation, graphing and statistical analysis.

Source of Information: Bangladesh J. Sci. Res. 22 (1&2): 13-26, 2009 (December)

Article Link (Online Journal):

Funding Source:

Total Budget (Tk.) :

Achievement/Findings:

As a poor country, Bangladesh desperately needs industrialization for its development. The tannery industries are very important as Bangladesh earns much more foreign currency from this sector but growth of these industries have caused a serious environmental problem because of the wastes and effluents that these industries are producing. These Industries have traditionally adhered to a minimum-cost production philosophy, overlooking social/environmental responsibilities. It naturally questions investment in effluent treatment which is considered as a non-productive activity but causing serious environmental pollution. Whereas, if these industries would have effluent treatment facilities, this could minimize the risk. Protecting the environment from industrial pollution however is not merely a problem of waste treatment. It is essentially a management problem. Waste is a misplaced resource and the challenge in wastes and effluents management is to identify a scheme of modifying inputs, modifying production processes and recovering by - products to make profits for industry while satisfying effluent standards. The city of Dhaka today is at the threshold of industrialization. More units for new products are being set up continuously. The errors of past should not be repeated; rather the lessons and knowledge from abroad should be utilized to create conditions suitable for man and infrastructures fit for environment. In this respect, considering the Bangladesh situation, installing ETPs in polluting industries, is strongly recommended.

Knowledge Management: Journal