Technologies of keeping livestock and management of manure pig complexes holdings built in the country under the Soviet regime no longer satisfy modern veterinary and environmental requirements. Conditions for the modernisation of such complexes were created as from 2000, when agricultural aid programmes (funds) appeared in Lithuania. Information about old and newly implemented manure management technologies, fertilisation value of manure, and quality of the drainage runoff from manure-fertilised fields has been collected in six large livestock companies. Analysis of collected data revealed that new livestock keeping, feeding and manure management technologies are more cost-effective in using energy and mineral resources and conform to the animal welfare, environmental protection and hygiene requirements that are becoming more and more stringent. As the traditional manure management in economic terms is quite expensive and has a significant impact on the environmental quality, academic community is looking for new manure processing methods. The global development of manure management technologies focuses on the manure processing in biogas plants. Biogas generated from liquid manure and animal waste in such plants is an alternative source of energy.

The research was made in the Šušvė river basin fertilized with organic fertilizer in the vicinity of a pig complex 'Litpirma' Ltd (25.0 thousand fattening pigs per year), Šiaulėnai local administration, Radviliškis district, in 2001-2006. This article presents total nitrogen concentrations and its amounts leaching from the complex to the basin, in the field drainage water and the Šušvė River (at a distance of 11.6 km from the pig complex). In the investigated Šušvė section, biologically treated wastewater from Šiaulėnai Township and the areas fertilized with organic fertilizers comes into the river. In total, 11.8 t of nitrogen come into the river, of which 4% (0.49 t) come from the township's wastewater, and the rest major part (96% or 11.3 t) is the drainage water coming from fertilized agricultural fields. The dynamics of nitrogen concentrations both in the river and in the drainage outlet is of a seasonal nature: in winter (January – March) concentrations were higher, and in warm season (April – November) – lower. The Šušvė pollution by total nitrogen, both above and below the pig complex activities range, almost all the research period was exceeding the limit (2 mg lE-1). Due to the pig complex activities and intensive agriculture, the runoff of nitrogen pollutants increases from 14.9 to 29.3% in the Šušvė River. This proves that the processes of spontaneous purification are not intensive enough to neutralize completely the pollution from such size pig complex in this particular section of the river.

Willows (Salix sp.) and reed canary grass (Phalaris arundinecea L.) (RCG) are fast growing perennial energy crop and potential cultures for recovering of cutaway peat lands. Cut away peat land soils are characterized by high acidity (pHKCl 2-3), high NH4**+1, and lack of P and K. Wood ash could be good liming agent and resource of potassium. Waste water sewage sludge (WWSS) compost is effective fertilizer and source of phosphorus. The objective of the study was to investigate the effect of application of WWSS compost and wood ash fertilizers of different doses on ingrown of willow cuttings and RCG in potted cultures. The wood ash addition of 10 g lE-1 and 20 g lE-1 to WWSS compost mix with peat from used query in proportions 1:1 and 4:1 were tested. The length of shoots and dry mass of shoots and roots were assessed to determine the effect of fertilization on growth of crops. Chemical analyses of growing media were performed to determine the content of main nutrient elements and pHKCl changes during season. The positive effect of fertilization on growth of crops was observed - an optimum dose for willows is (10 g lE-1) equivalent to 10 tDM haE-1 wood ash with mix of WWSS compost with peat. RCG produces more biomass in growing media containing largest doses of wood ash and WWSS compost premix. The willows produced bigger amount of biomass and accumulated more nutrients from growing media than RCG.

Lake sediments have a broad range of elementary and organic substance content. Bottom sediments collect decaying organic debris of aquatic plants and animals mixed by water drift with mineral constituents - deposited in the bottom of the lake in anoxic conditions. Lake Alūksne is situated in Northeast Latvia and is of glacial origin. Its water and bottom sediments chemical content depends on formation conditions – influenced also by anthropogenic activities. In order to determine environmental quality for restoration purposes and sediment recovery, geochemical research is needed. This paper aims to study bottom sediments – texture, ash part, organic compounds and metals to pinpoint necessary steps that are crucial for distinguishing environmental quality of the lake through geochemistry research. Bottom sediments contain sapropel with large admixture of organic compounds and microelements that may significantly influence biota and human health if concentration exceeds natural background levels. When bottom sediments are recovered, it may improve oxygene conditions in the lake, extracted sapropel can be used as a fertilizer, therapeutic agents, supplements for farm foods. Generally, sapropel is improving the structure of agricultural soils, increasing the cation exchange capacity and serving as binding material for complexes formation; thus diminishing ecotoxicological exposure threats of heavy metals, increasing yields and albumen and protein quantity in plants cultivation products. As these sediments can be used for soil fertilizing and crop production improvement in agriculture, mechanisms of ecotoxicological impact to various soil types and agricultural plant ecology should be researched.

Triticale (×Triticosecale Wittmack) is a promising cereal crop that has a number of economically valuable properties that are absent in wheat (Triticum aestivum L.). The research was conducted at Uman National University of Horticulture (Ukraine) in a long-term stationary experiment, founded in 1964. The aim of the work was to study the influence of long-term application of different fertilizer systems (mineral, organic and organo-mineral) on the yield and grain quality of spring triticale. It has been established that in the conditions of high air temperature and soil moisture deficit, mineral and organo-mineral fertilizer systems have an advantage. In sufficient wet conditions, all studied fertilizer systems are highly efficient. Spring triticale (Kharkiv Hlibodar variety) has a high reaction to fertilizers, as grain yield increases from 6.3–6.6 to 9.0–9.5 t haE−1 (р≤0.05). Mineral and organo-mineral fertilizer systems have the greatest effect on protein content. In conditions of sufficient moisture, all levels of mineral and organo-mineral fertilizer systems significantly increase the protein content in spring triticale grain. In arid conditions, saturation of crop rotation area with N90P90K90 (M2), N135P135K135 (M3) and Manure 9 t +N46P68K36 (OM2), Manure 13.5 t + N69P102K54 (OM3) is preferred. It should be noted that spring triticale is quite reactive with fertilizers, as the protein content increases from 13.2–14.0 to 15.2–16.0% (р≤0.05) depending on the fertilizer system. The high influence of fertilizer system and year factors on yield and protein content in triticale grain has been established. It should be noted that spring triticale grain yield varies most from the weather conditions of the growing season.

There is an increasing demand in the development of new and better types of organic plant fertilizers. The aim of the present study was to evaluate if the beneficial effect of vermicompost on plant growth and development could be further promoted by adding different amounts of bat guano using two model species under controlled conditions, as well as to assess the microbiological characteristics of bat guano and soil after its application. The study was performed at the Faculty of Biology, University of Latvia, during 2013 and 2014. The amount of bacteria was significantly lower in guano in comparison to vermicompost samples. No actinobacteria were present, but yeasts were found in the guano sample. Soil fungal populations after the application of organic fertilizer from vermicompost and bat guano were dominated by potentially plant growth promoting fungi Trichoderma and Mortierella. However, at increased guano concentration (300 g kg˗1) the proportion of potentially plant pathogenic fungi significantly increased. Addition of bat guano to vermicompost fertilizer significantly enhanced the positive effect of the fertilizer on growth and development of winter rye (Secale cereale L.) and potato (Solanum tuberosum L.) plants.

The field experiment of IOSDV (set up in Tartu in 1989) with application of mineral nitrogen fertilizer in combination with different forms of organic fertilizer (manure, straw) during 2 years has led to changes in mineral nitrogen level depending on fertilization regime used. Crop rotation was the following: potato-spring-wheat-spring-barley. The weather conditions during the period of the study were rather different and it appeared that weather conditions are more important factors in determining mineral nitrogen content and crop yields than applying fertilizers.

In April 2021, the Sri Lankan Government banned imports of agrochemicals, including chemical fertilizers, to make Sri Lanka the first fully organic and chemical fertilizer-free country globally. The ban was justified by human and environmental health concerns, such as many cases of kidney failure in the central parts of Sri Lanka. While previous policies had envisioned a stepwise transition, the sudden ban jolted the agriculture sector. However, it was aligned with the emerging national economic crisis with drastically declining foreign exchange reserves that restricted the import of commodities, including fertilizer for distribution at subsidized prices. The ban was also opportune because fertilizer prices peaked on international markets in 2022. Without any transitional time, the thrust for organic fertilizers failed to satisfy demand or obtain the required crop nutrients resulting in severe agricultural losses. After the first data on decreasing yields were revealed, the government lifted the chemical fertilizer ban on December 1, 2021, but it was too late as the cropping season had arrived. Without financial reserves to import fertilizer, the donor community was urged to assist. This paper addresses: (1) justification of the ban, (2) the feasibility of transitioning to organic fertilizers based on the available biomass to replace chemical fertilizers; and (3) the related cost implications. The scenarios focus on irrigated paddy rice and the plantation sector that underpin the national economy. Undervalued nutrient sources are also considered as well as the constraints to and implications of such a transition beyond Sri Lanka’s frontiers.