There is little information on the amounts of carbon that can be added to soil by crop roots in irrigated cotton rotations. Measurements were made near Narrabri, northern NSW. The experimental treatments were: continuous cotton; cotton–vetch (CV); cotton–wheat (CW); and cotton–wheat–vetch. Carbon sequestered by rotation crop roots was estimated to be ~0.34 t C/ha.year for the vetch and wheat crops in the CWV rotation, 0.10 t C/ha.year for vetch in CV, and 0.08 t C/ha.year for wheat in CW.

Despite the consideration of prescribed early burning in the current management policy of State forests in the savanna-woodlands of West Africa, substantial uncontrolled burnings occur during the dry season. To increase understanding of the ecological impacts of those fires, we examined the effects fire seasonality on soil CO₂ efflux, hydrology and root biomass. The study provides important baseline data for comparison in future. The findings suggest that the impact of fire on soil parameters is largely dependent on seasonality.

Understanding the current status of urban-suburban forest remnants is crucial for their sustainable conservation, especially under elevated nitrogen deposition and frequent reforestation. Our results show that remnant forests in the urbanized Pearl River Delta have generally experienced high risk of aluminum (Al), acidity stresses, and non-acidic cation deficiencies for forest growth; reforestation may further reduce soil exchangeable potassium (K) and magnesium (Mg). Liming and fertilization are suggested to ameliorate those stresses particularly high Al and low Mg on the rapid urbanization-impacted forests.

Nitrogen (N) leaching frequently leads to productivity losses and negative environmental consequences. Two amendments, clay and biochar were investigated to ameliorate N leaching from coarse-textured soils. There was no difference in NH₄⁺ or dissolved organic N leaching between the amendments but a significant difference in NO₃^– leaching was detected. We conclude that to decrease N leaching, land managers should apply the most readily available of the amendments in the most convenient manner.

We need to develop studies to determine the actual environmental impact of agricultural practices in terms of CO₂ emissions. This paper compares the emissions produced by using two different types of poultry manures in different soils, and concluded that the most important factors were the characteristics of soils and manures and the timing to application. It is very important to give farmers information about using these products to reduce emissions and increase crop yields.

Sediments accumulated in roads from vehicle activity may contain high concentration of heavy metals which can be washed by rain into rivers and ponds and pollute them. Road sediments collected in major highways in Australia showed accumulation in copper and zinc at concentrations much higher than soils. Copper may have originated from brakes and zinc from tyres. Of the metals in the sediments, zinc appears to be more mobile and available to living organisms causing toxicity.

The application of different organic resource materials not only improves soil physical properties and maintains soil health but also reduces arsenic build up in soils. The extent of arsenic pollution in ground water and soils are consistently increasing in Bengal Delta Plains of India and hence enters into human body through foodweb causing various anomalies like carcinogenesis , arsenicosis etc. The mitigation of arsenic contamination might be possible due to complexation of less toxic organo-arsenic compounds as well as its retention on soil colloids.

Phosphorus (P) fertilisers are largely used in agriculture and their reactions in soils determine P availabilty for crops. It was observed that plant-available P will be decreased and transformed to less available forms at various miosture levels and could be accumulated in soils. Therefore, P fertilisers recommendation should be made carefully with due consideration for consequent changes of P fertilisers in soils.