Tapas Kumar Biswas

• Doctor of Philosophy
• Senior Research Scientist at The Commonwealth Scientific and Industrial Research Organisation

Pyrite in acid sulfate soils can get oxidised during drought resulting in severe soil and water acidification (pH < 4).The frequency and severity of drought and flooding is increasing in many regions of the world due to climate change but there has been limited research on the ability of acid sulfate soils to recover from these events. We studied t...

The FILTER (Filtration and Irrigated cropping for Land Treatment and Effluent Reuse) technique was developed to provide a sustainable system for treatment of saline sewage effluent on naturally occurring saline and/or sodic soils. Potentially, it can also be used to ameliorate soils that are salinised by inappropriate application of saline effluent...

Intensive rural industry is developing rapidly in parts of inland Australia. The usually nutrient and salt rich effluent from these sources has traditionally been disposed to both land and water bodies. Since direct water discharge is no longer permitted, a challenge now exists when applying effluent to land especially where the rate of application...

Knowledge of soil water composition is critical for sustainable crop production. Changes in soil water salinity and chemistry under irrigated plantings can be monitored in-situ with the SoluSAMPLER™.

Integrated biosystems form functional connections between different food production systems where the wastes of one system become resources in another to enhance the triple bottom line (economic, environment and social benefits). There is a critical need to develop dynamic crop biosystems given the increasing shrinkage of limited water resources an...

Many of the world’s rivers have been found to be sources of CO2 to the atmosphere, however, there has been limited assessment in arid regions. This analysis of a long-term (1979–2013) dataset (n = 3496) along Australia’s largest river system (River Murray) showed that there were sustained high pCO2 (carbon dioxide partial pressure) levels, ranging...

During the 2019–2020 Australian bushfire season, large expanses (~47%) of agricultural and forested land in the Upper Murray River catchment of southeastern (SE) Australia were burned. Storm activity and rainfall following the fires increased sediment loads in rivers, resulting in localized fish kills and widespread water-quality deterioration. We...

Following the 2019/20 Black Summer bushfires, rainfall can wash huge volumes of ash and debris from burnt vegetation and exposed soil into rivers. Fires can also lead to soil “hydrophobia”, where soil refuses to absorb water, which can generate more runoff at higher intensity. Ash and contaminants from the fire, including toxic metals, carbon and f...

Extensive bushfires in 2019-20 burnt large parts of forested and rural regions in south east NSW and north-eastern Victoria. These bushfires degraded water quality and altered the dynamics of river, lake and estuarian ecosystems. As loss of vegetation and parched soil surface make the fire affected area more erodible, most critical impacts occur fo...

The period of 2019-20 shall be remembered for its devastating bushfires across the east of Australia. In the Murray-Darling Basin, fires burnt about 5,000 Km2 of forested and rural regions in south east NSW and north-eastern Victoria, an important water catchment for the Murray River. Extensive bushfires in the Upper Murray catchment resulted in ex...

To understand how the Southern Spring Flow event influenced productivity along the length of the Murray River two complementary monitoring programs were carried out. In the first program, field measurements were taken each week along the Murray at 21 sites for 15 weeks to determine the concentrations and loads of carbon, nutrients and algae (measur...

Global temperature is steadily increasing and so is for freshwater demand. The world population today is 7.7 billion and is currently growing by approximately 83 million people every year causing increased demand for clean freshwater. The nexus between rapid population growth, infrastructure development, increased agricultural demands and global wa...

The aim of this paper was to analyse the spatial and temporal patterns and drivers of water quality in a large arid/semi-arid river system (River Murray, Australia) using a long term (1978 − 2015) dataset collected from 24 monitoring sites. The water quality is highly variable, but on average electrical conductivity (EC), pH, turbidity, dissolved a...

Blue-green algae (cyanobacteria) have always been present m the Murray River system and blooms are a natural phenomenon Australia's sunny climate and highly variable rainfall makes it particularly susceptible to blue-green algal blooms These are concerning as blue-green algae produce hepatoxins (liver toxins and are carcinogens), neurotoxins and de...

The Murray-Darling Basin is Australia's most important river Basin and contains three longest rivers-the Murray (2,530 km), the Darling (2,740 km) and the Murrumbidgee (1,690 km). Taking up 14% of the Australia's landmass, the Basin covers over a million km 2 and sits within four States (Queensland, New South Wales, Victoria and South Australia) an...

Discharge of acidic drainage from mining operations or acid sulfate soils can create severe environmental impacts if not managed appropriately. We tested different hydro-geochemical models to predict pH and dissolved Al, Fe and Mn concentrations and speciation following discharge and mixing of acid drainage into receiving waters; (1) an end member...

The physico-chemical monitoring component of the Water Quality Monitoring Program (WQMP) was designed by the Commission’s intergovernmental Water Quality Committee and published in 1979. It was subsequently amended slightly in 1980 and 1983. The data was reviewed in 1988 and 1999 with further analysis of trends in 2002. In 2005 another review led t...

This book begins with a review of the history of biofuel. It contains chapters that are devoted to emerging technologies for biofuel production, cell wall structure and destructing approaches, cellulosic biofuel crops role in phytoremediation, and feedstock pretreatment methods. Detailed discussion on the physiological and genetic research challeng...

Floods in the Murray Darling Basin have traditionally been associated with mobilisation of large quantity of salts. When flows receded the salinity of river water, particularly for the downstream users, on some occasions exceeded the Australian Drinking Water Quality Guideline limit of 800EC (500 mg/L). Schedule B of the Water Act (2007) states tha...

The lower Murray region below Swan Hill overlies a natural groundwater system with salinity approaching seawater. Irrigation induced salinity threatens the water resource for both the irrigation communities and downstream urban users. Analyses of the induced salt loads require an assessment of the past and current recharge to the aquifers. This pap...

This paper will focus on risks to agriculture and environment from in-stream salinisation, and discuss success and challenges of interventions in controlling salinity in the M-D Basin.

In Australia and most countries, increasing demands for high quality water resources, arable land, food and fossil fuels are greater than the sustainable, economic supply. This report presents research on the perennial, rhizomatous grass, giant reed (Arundo donax) to assess its use: 1. On marginal lands and wastewaters or saline ground waters, to p...

Australian irrigators are under considerable pressure to increase irrigation efficiency and reduce deep drainage, driven by environmental and economic imperatives. Capacitance probe sensors are relatively cheap and popular electromagnetic equipment to measure soil water content. A field experiment was performed with capacitance probe in Mallee area...

There are no shortages of poor quality water and lands in Australia. Ongoing droughtin many regions has renewed interest in alternate uses of saline wastewater rather thandisposal to evaporation basins. This paper reports on the underutilised resources ofwastewater and saline land to grow a new second generation biofuel crop, namely Arundodonax L....

Mankind’s demands for high quality water resources, arable land and fossil fuels are greater than the sustainable supply in many countries. The perennial grass Arundo donax (Adx), giant reed produced more cellulosic biomass (over 45 dry t/ha/year when irrigated with wastewater) using less land, fertilizer and without pesticides than any alternative...

Subsurface drip irrigation (SDI) is the placement of the dripper line below the soil surface at a certain depth depending on the location of the rootzone of the crop to be grown. The dripper line may be permanent as in perennial plantings or annually installed as for some row crops. SDI is the latest and possibly the most sophisticated and efficien...

There are no shortages of poor quality water and lands in Australia. Ongoing drought in many regions has renewed and increased interest in alternate uses of saline wastewater rather than disposal to evaporation basins. This paper reports on the underutilised resources of wastewater and saline land to grow a new second generation biofuel crop, namel...

Certain agricultural crops can produce very large biomass and at the same time act as biofiltering systems to treat wastewaters, thus recycling nutrients and water, and producing value added products. Overseas research has shown the high annual growth and cellulose content make giant reed a potential crop for converting solar energy to industrial f...

The existing Water Allocation Plan for the River Murray Prescribed Water Course encourages Riverland growers to achieve a water use efficiency of at least 85%. Water use efficiency (WUE) has been defined as the volume of water used "consumptively" by the crop i.e., evapotranspiration divided by the total volume applied to the field. The increase in...

The horticulture industry has been increasingly adopting the practice of high but precise water and fertilizer input to obtain faster returns, larger yields and better quality fruit. Open hydroponics, an Advanced Fertigation (AF) technique, is one such precision fertigation practice that maintains a restricted wetted zone by using low application r...

Increasing salinity of irrigation water is one of the biggest threats facing wine grape production in the Lower Murray region of South Australia. The Currency Creek/Finniss wine region relies heavily on sourcing irrigation water from the predominantly winter rainfall charged streams of the Eastern Mt Lofty Ranges. During the peak growing season flo...

Growers practicing precision irrigation in semiarid and arid regions are increasingly experiencing gradual accumulation of salt in the crops root zone. Many Australian grape growers in south eastern Australia have reported elevated levels of sodium and chloride in leaves, berries and wine. Highly efficient irrigation with moderately saline water of...

The salinity of the Lower Murray is episodically high. Following the adoption of efficient irrigation practices, irrigators in the Lower Murray region have noticed high salinity levels in the root zone, despite the relatively low salinity irrigation water in recent years. Highly efficient irrigation in this semiarid climate results in elevated leve...

Onion growers in Australia, whose product accounts for a gross value of $155 million, are facing serious challenges in their industry, among them reduced water supplies, increased input costs and the threat of rising salinity. These issues, together with the ongoing demand from markets to produce a top-quality product, increases the importance of p...

Salinity refers to the total amount of salts present in soil or water. In Australia salinity is dominated by sodium chloride salt (closely related to common or household salt) but most soils and water also contain salts of calcium, magnesium, potassium, carbonate, bicarbonate, sulphate, borate and nitrate. While some salts such as fertiliser can be...

This module consolidates current information and thinking around the pros and cons of subsurface drip irrigation in relation to conventional drip irrigation (both raised on a wire and laid on ground). It briefly highlights a number of other novel irrigation management tools that may either be close to commercialization (e.g. infra-red thermography,...

Improvements in water use efficiency (WUE), through the adoption of precision irrigation practices, have led to significant water savings in the semi-arid region of the Lower Murray River. Precision irrigators in this region are achieving greater than 85% irrigation efficiency (Stevens 2002), where annual average rainfall is 250 mm. A by-product of hi...

First generation biofuels are made from edible components of food crops while second generation biofuels are processed from agriculture and forestry wastes or from non food, cellulosic biomass crops. During the next decade, we have the opportunity to develop sustainable biosystems to produce higher yield, non food, biomass crops grown on saline lan...

Vignerons practicing precision irrigation in South Australia are increasingly experiencing accumulation of salt in the root zone as well as elevated levels of sodium and chloride in juice. This is contributing to wine quality deterioration. There is an increasing need from growers to monitor and manage the root zone salinity. A comparative assessme...

In the past two decades many grape growers have converted to pressurized irrigation systems in order to improve wine grape quality, yield consistency and improved water use efficiency. Many growers in the SA Riverland have now achieved the target 85% water use efficiency. As growers become more efficient in their irrigation water use they are confr...

In the past decade semi-arid region of Lower Murray River growers have converted to pressurized irrigation systems and many achieved water use efficiency (WUE) of at least 85%. The driving forces are: (i) Grape growing under controlled water stress for quality wine, (ii) ‘wine boom’ enabled progressive growers to change over to precision irrigation...

In the past decade semi-arid region of Lower Murray River growers have converted to pressurized irrigation systems and many achieved water use efficiency (WUE) of at least 85%. The driving forces are: (i) Grape growing under controlled water stress for quality wine, (ii) ‘wine boom’ enabled progressive growers to change over to precision irrigation...

Irrigation is a human devised process for changing the natural water balance at a point in the landscape with the desire to enhance the plant production. In addition to the water that is applied solutes are also applied. These additional solutes which can come from various sources are often just dissolved in the irrigation water. Solutes can often...

During the past two decades, improved irrigation practices in the Lower Murray horticultural districts have raised Water Use Efficiency (WUE) from about 50 to 85%. Consequently the drainage volumes were reduced from 50 % to 15% of water applied. The increase in WUE has caused a risk of salt build up in the root zone due to insufficient leaching of...

Root Zone drainage, commonly called ‘deep drainage (DD)’ is the prime important factor influencing on and off-site impact of irrigation on the local landscape. In the South Australian Riverland districts DD becomes recharge to the underlying highly saline aquifers and accelerates the natural saline seepage into the Murray River. A ‘curtain’ of sali...

This paper considers the design and management of irrigation systems using reclaimed water in terms of irrigation supply volume and quality, reductions in environmental degradation and maintenance of crop production. The irrigation water requirements including crop water requirements, determination of evapotranspiration and crop water requirement i...

Due to improved irrigation management and system upgrades, the field application efficiency (FAE) in the Lower Murray horticultural districts has risen from about 50 to 85% during the past 2 decades. Consequently, the drainage volumes have reduced from about 50 % to 15% of water applied. Under steady state conditions, the salinity in the root zone...

Technology and economic development has led to the growth of megacities and urban centres with populations in the millions. Such population expansion and densification increases the strain on wastewater collection and treatment infrastructure, which has been largely based on an end-of-line centralised model. However, in megacities new challenges ar...

Irrigated horticulture in the Lower Murray (Riverland-Sunraysia) region has improved water use efficiency (WUE) over the past two decades from about 50% to about 80% as a result of improved irrigation practices. The one negative consequence of this achievement is an emerging risk of salinity build-up in the root zone, threatening the sustainability...

Over the years growers in the Lower Murray-Darling irrigation districts have consistently reported salinity damage to horticultural crops despite the moderate irrigation water salinity. There is also anecdotal information that after leaching the salinity in the root zone remains higher than expected, perceived due to incomplete mixing of the soil s...

Wastewater need not be disposed to an evaporation basin until all useful benefit has been extracted from the waste stream. Sequential Biological Concentration (SBC) of saline drainage streams offers the ability to create a number of financial opportunities, whilst concentrating the waste stream to a manageable volume. In this paper, we present fie...

Irrigated horticulture in the Lower Murray (Riverland-Sunraysia) region has an annual gate-value of about $ 2.5 billion. One aspect of the recent improvements in irrigation practices, reduced drainage, increases the risk of salinity build-up in the root zone. Such a build-up would threaten the sustainability of horticulture in this region. During...

Drought has focused Australia's attention on our water resources, reawakening the debate on equitable distribution, security of access rights for water and the impact of commercial production on the environment'. (Murrumbidgee Irrigation Annual Report, 2002–03). Will the advent of the inevitable 'flooding rains' quell the debate, or is it here to s...

This chapter describes existing systems for wastewater renovation and reuse; the FILTER (Filtration and Irrigated Cropping for Land Treatment and Effluent Reuse) technique; Field evaluation of the FILTER system; Pollutant removal through the FILTER system; Maintaining macropore stability and flow rates through the filter plots; and Potential use of...

The use of urban wastewater in agriculture is a widely established practice for alleviating water scarcity situations and reducing or even eliminating the purchase of chemical fertilizers. However, unregulated irrigation with untreated wastewater poses serious public health risks, as sewage is a major source of excreted pathogens that cause gastro-...

The most common source of elevated As concentrations in the Australian environment are attributable to anthropogenic activities. Mining activities have contributed to the contamination of soil and water primarily in Western Australia and Victoria. However, other anthropogenic activities such as agriculture, forestry and industry have also contamina...

Copper (Cu) derived from fungicides was investigated in soils, plants, fruits and juice from vineyards. Sub-surface drainage water and evaporation basins for these vineyards were also investigated. The results showed an accumulation of Cu in the top 5 cm of soil compared to neighbouring non-horticultural and uncultivated lands. Although high levels...

The Australian community is increasingly unwilling to accept the discharge of sewage effluent to sea, rivers, lakes or watercourses. To reduce pollution of water bodies, CSIRO Land and Water has developed a new technique called ‘FILTER (Filtration and Irrigated Cropping for Land Treatment and Effluent Reuse)’ to treat and reuse sewage effluent in a...

In traditional land based irrigation scheme, large storage is usually required when evapotranspiration demand is low during winter and wet weather. In addition, threats to long-term sustainability including salinisation, sodification, waterlogging, and nutrient and heavy metal pollution of the reuse site are also common particularly, in soils with...

In order to address the disposal problem of salty drainage water from one of the largest irrigation areas in Australia, a serial biological concentration (SBC) of salt approach, which optimises wastewater re-use and concentrates salt for harvesting is being trialled on an area of 10.5 ha of saline-sodic red brown earth soil, in the Murrumbidgee irr...

We will take the title given as irrigation keeping ahead of its detractors and continuing to fulfill its fundamentally necessary destiny. However we see irrigation as sitting on the horns of a dilemma, on the one hand it is required to produce more food for a burgeoning world population (10 billion by 2050, Abdulla 1995), on the other it must do th...

Land treatment of wastewater using cropping and forestry are often considered less economical than engineering solutions due to cost of winter and wet weather storage and adverse impacts on reuse site. In order to overcome problems associated with traditional wastewater disposal schemes, the FILTER (Filtration and Irrigated Cropping for Land Treatm...

Existing systems for land treatment of wastewater using cropping and forestry are often less economical than treatment plants. This is mainly due to the need for expensive winter and wet weather storage, when crop irrigation requirements are low. Further, conventional land application of wastewater on soils with restricted internal drainage, which...

Intensive rural industry is developing rapidly in parts of inland Australia. The usually nutrient and salt rich effluent from these sources has traditionally been disposed to both land and water bodies. Since direct water discharge is no longer permitted, a challenge now exists when applying effluent to land especially where the rate of application...

Introduction Large-scale intensive rural industries and sewage treatment plants in rural New South Wales have attracted the interest of community and regulatory authorities because of the potential of their effluents to contaminate land and water resources. Concern for the environment has made it preferable to recycle these effluents for irrigated...

Throughout the world N is the plant nutrient most limiting in soils growing rice. Inadequate nitrogen nutrition is the major nutritional constraint to rice production. Moreover, fertilizer N use efficiency is also very low (20-40%) in lowland rice due to its loss to atmosphere through ammonia volatilization, denitrification and leaching. Low effici...