Carbon Sequestration Under Different Agricultural Land Use in Croatia

Abstract

In order to help mitigate climate change, carbon farming methods must be urgently introduced. The research systematically reviewed peer-reviewed literature, national statistical reports, and policy documents published between 2000 and 2024, focusing on the impact of land management on soil organic carbon in Croatia. This paper provides an overview of current agricultural practices on croplands and grasslands in Croatia. It identifies the weak points of current soil management and suggests possible measures for carbon sequestration in cropland and grassland soils. About 89% of Croatian soils are tilled conventionally, along with other harmful practices such as uncontrolled grazing and improper fertilization, which contribute to increasing carbon losses and soil degradation. Different practices are presented and discussed as possible solutions, each adapted to the specific environmental and soil conditions of Croatia. For example, studies in Croatian Stagnosols report 5% lower CO₂ emissions under conservation tillage compared to conventional tillage, while long-term grass cover in perennial croplands has shown soil organic carbon increases of up to 51%. The recommendations are categorised according to the possibility of a change in carbon stocks over time and the associated carbon storage potential. Croatia needs to recognize any shortcomings in the existing system and create incentives and policies to transform management practices into site and environment-specific regional practices.

1. Background

Global greenhouse gas (GHG) emissions have continued to increase due to unsustainable energy use, land use and land-use change, lifestyles, and production patterns [1]. The global average temperature over land has risen by around 1.5 °C, accelerating many weather and climate extremes across all regions [1]. Europe is warming faster than the global average. The mean annual temperature over European land areas over the last 10 years has been 2.04 to 2.10 °C warmer than in pre-industrial times. This poses a threat to humanity as climate change puts additional pressure on food security through droughts, floods, pests, and diseases [2].

Food production is responsible for 25–30% of annual CO₂ emissions and is, therefore, one of the main causes of the climate crisis [3]. Conventional agriculture ensures current food production, but at the same time promotes soil degradation and GHG emissions [4]. Only 30–40% of European soils are healthy [5]. Policy makers responded by introducing the “Green Deal”, which, together with the United Nations “2030 Agenda for Sustainable Development”, aims to create a link between a healthy planet, food security in the face of climate change, and a world without soil degradation. Conventional practices in agricultural systems need to be changed to ensure and maintain soil health by storing carbon (C) in the soil. Currently, 38% of the world’s land area is used for agriculture [6], indicating a high potential for C sequestration and storage to combat climate change. A high C content makes soils more resilient to climate extremes and other degradation problems such as anthropogenic compaction, soil erosion, settling, crusting, reduced water storage, and nutrient supply [7].

As an EU member state, Croatia has committed to achieving climate neutrality by 2050, as set out in the European Green Deal and supported by the Common Agricultural Policy (CAP) 2023–2027. National policies such as the CAP Strategic Plan for 2023–2027 and the commitments under the Land Use, Land-Use Change and Forestry (LULUCF) Regulation (EU 2023/839) emphasise the importance of sustainable land management. The Croatian agricultural sector contributes significantly to national GHG emissions and is, therefore, a priority for the implementation of mitigation strategies. By adapting to this framework, Croatia seeks to improve carbon sequestration and adapt to future climate scenarios.

In transitioning to a more sustainable agricultural system, Croatia faces both challenges and opportunities. The World Bank’s assessment of Croatia’s agricultural sector [8] emphasises the potential for a leap to green growth, as the country has been relatively less reliant on intensive agricultural practices in the past compared to older EU members. However, significant structural challenges remain, including small farm sizes, weak producer cooperatives, and the need for improved extension services and digitalization. These constraints can limit the adoption of carbon-friendly practices as they reduce economies of scale for investment in new equipment, limit collective bargaining power for sustainable inputs, and slow down knowledge transfer and technical capacity building among farmers. Inadequate digital infrastructure also hinders access to precision farming tools, carbon monitoring systems, and online training resources.

Previous Croatian and regional studies have applied different approaches to assess soil carbon dynamics and mitigation potential, including direct CO₂ flux measurements under different tillage systems [9], long-term monitoring of soil organic C under different mineral fertilization regimes [10], and comparison of the impact of management practices on C stocks [11]. Taken together, these studies provide important evidence, but also reveal gaps, especially in multi-site trials under Croatian conditions.

Croatian agricultural policies, such as the National Agriculture and Rural Development Strategy (NARDS) and the National Strategic Plan (NSP) for the CAP, emphasise sustainable land management, agroecological practices, and climate resilience. These frameworks particularly emphasize the introduction of conservation tillage, organic fertilization, rotational grazing, and agroforestry to improve carbon sequestration. Rural development measures also provide financial incentives for sustainable practices and support data-driven decision-making through improved monitoring systems. By aligning national policies with EU targets, Croatia can gain access to financial resources and technical support to accelerate the transition to a more resilient agricultural sector.

To achieve this transition, site- and region-specific agricultural management measures should be trialed and implemented after evaluation. Recently, there have been several research papers looking at the benefits of different practices to reduce the impact of climate change on soil degradation and C sequestration in Croatia [9,12,13,14,15,16]. However, most studies were conducted under specific soil and climate conditions at a single site. Moreover, they were conducted holistically for a single land use, and the studies do not focus on the different agricultural practices for C sequestration in Croatian agricultural landscapes. It is important to know the current soil management practices in the different land-use types in Croatia and how they can effectively sequester C in Croatian soils. This work focuses mainly on the current management practices and the potential for C sequestration in Croatia.

2. Methodology

This review used a structured approach to identify relevant literature and data sources. Given the limited number of scientific publications dealing specifically with soil C sequestration in Croatia, the search included publications and datasets from 2000 to 2024. Sources were identified by combinations of keywords, such as “soil carbon sequestration”, “agricultural management”, “Croatia”, “Mediterranean”, and “Continental climate” in Web of Science, Scopus, and Google Scholar. In addition, institutional repositories and government portals were searched for official reports. The following categories were considered: (i) national reports and policy documents, including those from the Ministry of Agriculture, the World Bank, and sectoral studies; (ii) international peer-reviewed articles on C sequestration methods applicable to Mediterranean and Continental European climate; (iii) government datasets and statistical records related to land use and agricultural emissions. Grey literature was considered when peer-reviewed sources were not available for the Croatian context, as Croatia is a small country with a limited number of researchers working directly on this topic. Although there is no fully integrated soil monitoring system in Croatia, regional monitoring programs and statistical records were used when available. The selection favored sources that provide empirical data, policy insights, or methodological frameworks relevant to Croatian agricultural landscapes. The synthesis of these different sources allowed for a comprehensive assessment of C sequestration potential under different land use and management practices, even in the absence of comprehensive national scientific studies.

3. Types of Carbon Sequestration Potential in Croatia

Several conservation measures in different land-use categories may be essential for C sequestration in Croatian soils. This is extremely important as the solutions for the introduction of conservation agriculture practices should be tested under different pedological, geomorphological, and environmental conditions. Bašić [17] divided the Croatian territory into three main agricultural regions: the Pannonian region, the Mountainous region, and the Adriatic region, which account for 51.2%, 16.5%, and 32.3% of agricultural land, respectively. Each region has very different conditions and different types of land use, namely grassland, annual cropland, and perennial cropland [18]. This review focuses on the Pannonian and Adriatic regions, as there is little peer-reviewed quantitative data on C sequestration in the Mountainous region. This region is characterized by steep slopes, shallow and skeletal soils, and low or abandoned agricultural land use, often remaining as semi-natural grasslands or forest–pasture mosaics. While these landscapes may have considerable potential for C storage, the lack of site-specific measurements limits the ability to draw quantitative conclusions. Qualitative findings from national reports and land-use statistics are included where available.

Given the limited number of studies on C sequestration in Croatian agricultural landscapes, a consolidated table summarizing the main findings for cropland and grassland is presented (

Table 1. Summary of carbon sequestration findings in Croatian agricultural and grassland systems across Mediterranean and Continental climates.

Practice	Land Use	Region	Impact on C Sequestration	Reference
Conventional tillage	Annual Cropland	Pannonian	Increases CO2 emission and reduces soil C	[15,19]
Conventional tillage	Annual Cropland	Adriatic	Increases CO2 emission and reduces soil C	[13,20]
No—tillage	Annual Cropland	Pannonian	Reduces CO2 emission by 5%	[9]
Mineral N fertilization	Annual Cropland	Pannonian	Improved soil organic C by 93%	[10]
Organic Fertilization	Annual Cropland	Adriatic	Improved soil organic C by 19%	[21]
Diverse Crop rotation	Annual Cropland	Pannonian	Enhanced soil organic C	[22]
Grass cover	Perennial Cropland	Pannonian	Increase C content by 33%	[23]
Grass cover	Perennial Cropland	Adriatic	Increase C content by 35%	[20]
Grass cover	Perennial Cropland	Adriatic	Increase C content by 51%	[11]
Grass cover	Perennial Cropland	Adriatic	Increase C content by 24%	[24]
Herbicide	Perennial Cropland	Adriatic	Decrease C content by 9%	[24]
Mineral fertilization	Perennial Cropland	Pannonian	44% higher C stocks	[25]
Moderate grazing	Grassland	Pannonian	Enhanced soil organic C by 41%	[26]
Legume use	Annual Cropland	Pannonian	Increase biomass C	[27]
Mineral N fertilization	Grassland	Pannonian	Increase biomass C	[28,29]
Mineral NPK fertilization	Grassland	Pannonian	Increase biomass C	[30]
Reduced stocking density	Grassland	Pannonian	Increase biomass C	[29,31]
Grass cover	Perennial Cropland	Pannonian	Increase C content by 85%	[14]
Wide crop rotation	Annual Cropland	Pannonian	Increase biomass C	[32]

). This table summarizes the best available data to support the discussion in the following sections and underlines the need for increased research efforts in Croatia to obtain more robust and region-specific results.

4. Current Practices and Carbon Sequestration Potential Under Annual Croplands

Croatia’s cropland comprises 27% of the total land area and is the second-largest category after forest land. The expansion of croplands brings many negative changes, as this category is the source of GHG emissions in the period 1990–2020 [33]. Croatian food production is not sufficient to cover domestic consumption, which leads to a possible future increase in productivity and expansion of croplands [34]. The justification for the expansion of cropland is a particular problem given the projected increase in food demand and the increased need for soil C sequestration [35]. Although intensification of agricultural production on existing croplands can minimize land-use change in natural landscapes, it exacerbates degradation, and global food productivity growth is declining [36]. Therefore, future policies should carefully consider all open aspects. Compared to grasslands and forests, croplands in Croatia contain a significantly lower concentration of C in soils [25,37]. Farmers in Croatia predominantly use conventional agronomic practices [12], i.e., frequent invertive tillage (Figure 1), multiple tractor passes, and the use of agrochemicals—all practices that have an impact on soil structure degradation, soil and C losses due to erosion, and increased C emissions [13,23]. According to the latest national statistics, conventional tillage was practised on 729,500 ha of arable land in 2023, representing 89% of the total area, compared to 10.7% with conservation tillage and only 0.1% with zero tillage [38]. This distribution has hardly changed in the last 10 years despite the incentives offered by the EU and Croatia in favour of sustainable practices.

Factors influencing changes in C on cropland include management practices in the Croatian agroecosystem: frequency and tillage system, type and length of crop rotation, organic fertilization and soil conditioners, and agricultural production (conventional, organic). These categories have a significant impact on soil C content in different ecosystems. Tillage is indispensable in the annual practice on agricultural soils in Croatia, although it has positive and negative effects on the agroecosystem. Conventional tillage, which includes practices that turn and fragment the topsoil (e.g., plowing, disking, rotary tillage), increases CO₂ emissions and reduces soil C content in the long term under temperate continental [14,19] and Mediterranean climatic conditions [13,20]. In contrast, conservation tillage promotes C sequestration (Figure 2). However, its prevalence in Croatia does not exceed 11% of the total arable land [38], and the widespread application of such systems in Croatia is still pending [39]. About 90% of farmers use plowing as a regular annual primary tillage [12]. Some larger farms that include winter crops in the crop rotation abandon plowing and apply reduced tillage with combined tools or even no-tillage of catch crops, thus introducing conservation tillage into regular practice.

The continuous practice of no-tillage is not yet widespread in Croatia, although no-tillage is occasionally practiced after crops with low crop residues (e.g., soybeans). In the eastern part of Pannonian Croatia, no-tillage is avoided after the harvest of winter crops, mainly due to fear of water scarcity [40]. Reduced one-pass tillage after maize harvest is a good management practice to reduce the frequency of soil aeration and CO₂ emissions. Bilandžija et al. [9] 2016 measured 5% higher CO₂ emissions on Stagnosols with conventional tillage compared to conservation tillage. While this difference is smaller than many values reported worldwide, it reflects one of the few cases measured under Croatian conditions and should be considered specific to the soil type, climate, and management context of the study.

Tillage in Adriatic Croatia is very uniform and conventional with disk plows (larger fields) and rototillers (small fields) or even hand tools in the case of small plots (Figure 3), which increases C losses [13] and accelerates erosion [11,24]. Sediment loss in Adriatic Croatia is estimated at 1.67 million tonnes of soil per year [17], which corresponds to a loss of 20,000 tonnes of organic matter [41].

Another reason for the change in C stocks on annual cropland is the amount of organic and mineral fertilizers applied. In Pannonian Croatia, a long-term (20–year) field experiment on Stagnosols with initially low organic C (1.4% in the top 0–30 cm) showed an increase in soil organic C by 93% (to 2.7%) with constant high mineral fertilization [10]. This site-specific result reflects the combined effects of low initial organic C content, sustained nutrient supply, and favorable climatic conditions for biomass production, and should not be generalized to all Croatian croplands. In contrast, a recent global meta-analysis found much smaller average changes in organic C due to variations in mineral N fertilization, confirming that the magnitude of the effect is highly dependent on initial soil organic C, soil type, climate, and management [42]. In Adriatic Croatia, a single application of farmyard manure (40 kg ha⁻¹) increased the organic C content of the soil by 19% within 4 years [21]. However, due to the lack of livestock [33], fertilisation in the Adriatic Croatia is predominantly mineral, leading to excessive or insufficient problems that affect crop production and the organic C cycle, as well as an increase in the loss of C from soils.

More diverse crop rotations have the potential to increase organic C and maintain biological balance. However, the “fixed shackles of crop rotation” have been removed from cropland in Croatia. Market demand and fluctuating prices have meant that diversified crop rotations are now only practiced on smaller areas, and free rotations, which are common in Croatia, are widespread, which has a negative impact on C sequestration [43]. At the same time, the diversity of crops in the rotation has also been affected by the negative effects of climate change [44]. Until the beginning of the century, spring barley and wheat were cultivated without major technological problems. In Pannonian Croatia, these crops were removed from the crop rotation because the soil conditions were unsuitable and quality sowing was not possible [40].

On the Pannonian-Croatian croplands, very often, only maize was grown in monoculture, especially on flood-prone areas or in double crop rotations, e.g., winter wheat-maize [17]. Such crop rotations have several disadvantages. From the point of view of fodder production and C sequestration, however, their fundamental disadvantage is that the production of quality fodder is completely excluded [22]. Crops for the production of livestock feed (clover, alfalfa, grass mixtures, clover-grass mixtures) create a larger organic mass in the soil through their rhizosphere growth and promote C sequestration [22]. An exception is rare farms that practice diverse crop rotations with several fields on areas that are not threatened by excess water. In the eastern part of Pannonian Croatia, crop rotation is diverse and includes the cultivation of rapeseed, sunflowers, barley, sugar beet, soybeans, and clover. The classic crop rotation can also be found in the sequence: wide-row spring crops—grain legumes—winter cereals. These crops have increased the quantity and quality of the C input. The cultivation of cover crops on croplands in Pannonian Croatia is not a regular practice. On more than 98% of annual croplands, no cover crops are grown in the period between the harvest of the previous crop and the preparation for sowing the next crop. Unfortunately, this percentage is even higher on croplands in Adriatic Croatia [45]. The scientific community in Croatia has yet to finalise studies on the influence of crop rotation, cropping patterns, and cropping duration on the C content of Croatian soils.

Carbon management is an essential aspect of a successful organic farming system. Organic farming traditionally relies on pre-sowing tillage and post-sowing mechanical weed control to reduce diseases, pests, and insects [22]. The reliance on tillage for weed control is often highlighted as a shortcoming of organic farming [46], as it can have a negative impact on soil C levels. However, when looking at soil structure and C content in organic and conventional systems, organic farming systems generally perform even better than conventional ones [47,48,49], mainly due to the supply of fresh organic matter through organic fertilizers, compost, green manures, and other organic by-products on organic farms, as well as well-designed crop rotations, which largely include the sowing of cover crops and perennial clovers [13].

Organic farmers in Croatia must apply the necessary practices to increase C sequestration. Although organic producers follow organic farming regulations [50] and do not use agrochemicals, other soil and cultivation practices are only superficial and are generally not applied. Croatian farmers use EU financial support, which is the main motivation for farmers, instead of applying good management practices [51]. In this way, biomass/yield productivity in organic farming is often low, which would allow for a positive impact of organic farming practices on soil C sequestration in Croatian organic farms.

5. Carbon Sequestration Under Perennial Croplands

Carbon sequestration in perennial croplands in Croatia depends on soil management practices and differs essentially between farmers who practice permanent grass cover and those who till the soil at least once during the growing season [19]. The positive effects of vegetation on C sequestration and mitigation of degradation processes have been reported in Croatia [11,14,20,23,24]. However, the predominant practice on most perennial croplands in Croatia is inter-row tillage and the use of non-selective herbicides in the rows [52], which leads to loss of organic matter, disruption of soil structure, crust formation, and increased susceptibility of the soil to compaction and erosion [24]. Most permanent crops in Croatia are planted on sloping soils and cultivated by tillage without cover crops and insufficient fertilization, which promotes erosion (Figure 4) and C loss, thus exacerbating the problem of soils poor in organic matter [53].

Farmers in Pannonian Croatia avoid revegetation, mainly for fear of competition between grass and crops for water and nutrients, but also because of potential problems with pests (e.g., voles). This type of cultivation is particularly pronounced in the first years after the establishment of vineyards and orchards [52]. The loss of organic C in the tilled soils reaches values between 12% and 47% in vineyards and between 7% and 41% in orchards compared to grass-covered soils in perennial croplands (Figure 5). The estimated area of grass-covered perennial cropland in Pannonian Croatia is 35%.

Fertilization of perennial croplands in Pannonian Croatia, i.e., the addition of large amounts of manure (usually between 20–40 t ha⁻¹) and mineral fertilizer (200–600 kg P₂O₅ and K₂O per ha) during planting, is high, followed by 2–3 mineral fertilizer applications during vegetation. This leads to nutrient-rich soils and increased growth of biomass—a source of organic C [17]. Bogunovic et al. [25] reported that the topsoil in orchards and vineyards contains 76% and 13% higher C stocks than annual cropland, respectively.

In Adriatic Croatia, water management is delicate: The water balance has two opposing conditions: a pronounced surplus in winter and a significant deficit in summer, which affects the possibility of plant cultivation, but also the strong mineralization of residues, which makes accumulation and storage in the form of permanent organic C difficult. In addition, organic C in Adriatic plantations is reduced to insufficient levels several times during vegetation by frequent tillage (usually with light discs or rototillers) [11,20,24,54].

About 10% of perennial cropland in the Adriatic is covered with grass, mainly in olive groves in Istria and in some karst areas where flooding occurs. Other smaller farmers, especially in stony and rocky areas, where the plots are tiny, mostly use non-selective herbicides or keep the soil in the plantations clean (Figure 6). C sequestration is low in these areas where primary crop production is reduced to low levels.

Such practices are not desirable in terms of C conservation. A comparison between grassed and tilled areas (vineyards, olive groves) shows that the loss of organic C in the tilled areas is 12% in the vineyard, between 15% and 32% in the olive groves, and 41% in the orchards (Figure 5). These losses are considerable and show the great potential for storing organic C in the future if regular conservation measures are implemented in the plantations. No cover crops are grown or mulched in the Adriatic Croatia plantations, nor is mulching [54]. Fertilization is highly variable; it is based on tradition, without using recommendations based on analyzes, and mineral fertilizers are mainly used instead of organic fertilizers.

6. Practices and C Sequestration Possibilities Under Grasslands

In Croatia, grassland accounts for 40.6% of the total utilized agricultural area [55]. According to the latest categorization from 2005, the ratio of meadows and pastures is about 1:3 [56]. In Croatia, grasslands are predominantly semi-natural habitats that have been created and maintained by humans and domestic animals over the millennia. This traditional and, by today’s standards, extensive management, which includes the avoidance of mineral fertilizers, mowing, and heavy grazing, has created and maintained a kind of mosaic of grassland habitats with high biodiversity [57,58,59]. The abandonment of the traditional, millennia-old practice of grassland utilization and the depopulation of the area in Croatia led to the degradation and conversion of grassland to forest. In contrast, grasslands on more fertile soils and in the lowlands were converted to croplands [60,61]. As a result of these trends, the total grassland area has decreased [55], jeopardizing biodiversity and the possibility of higher C storage (biomass and soil).

Considering the region (Adriatic, Pannonia) and the ecological and pedological conditions, grassland management practices in Croatia differ significantly. Insufficient fertilization, delayed mowing, and uncontrolled grazing are the main problems in grassland management in Croatia. There is no tradition of grazing management across most of Croatia [57]. The majority of pastures (85%) are natural systems [62]. Fertilization of pastures and meadows is rare in Croatia, and general investments to increase productivity and biomass growth are mostly non-existent [30]. The management of pastures and meadows in Croatia varies due to the geographical location. Most grasslands in Adriatic Croatia are natural pastures (Figure 7) with very low biomass productivity due to lack of fertilization, maintenance, and rotational grazing [57], resulting in low C sequestration.

Significant grazing areas are located at higher altitudes, where environmental conditions only allow grazing during 3–4 summer months. On them, there are few opportunities to secure biomass [60], which further favors the accumulation of organic C. Most of the best meadows in Adriatic Croatia have been converted to arable land, decreasing their C content [17], and the remaining meadows are predominantly unfertilized [63].

Although livestock farming plays the most important role for the survival of the population in Croatia, today’s socio-economic changes and the poor economic results of livestock farming have made this occupation undesirable [26]. Nevertheless, the remaining producers are practicing more intensive livestock farming and achieving good economic results, which indicates that certain pastures are suffering from possible overgrazing. Overgrazing can occur on all pastures (farms) where uncontrolled continuous grazing is practiced (Figure 8). Overgrazing increases soil compaction, reduces biomass production, and accelerates erosion and C losses more than moderate grazing [26].

7. Possibilities and Recommendations

The recommendations in this section are now more explicitly linked to Croatia’s national and EU-level policy framework. The CAP 2023–2027 introduces a results-based approach to sustainability, and the Croatian NSP is aligned with these objectives through eco-programmes and agri-environmental measures that promote sustainable land use. The World Bank’s findings also emphasize the importance of strengthening agricultural knowledge systems and extension services to support farmers in adopting sustainable practices.

The Croatian agricultural sector is at a crucial stage where EU and national policies provide a framework for transformative change. Alignment between scientific recommendations, policy incentives, and farmer adoption will be key to sustainable agricultural growth and improved carbon sequestration.

7.1. Legume Use

This strategy covers croplands and grassland areas, which are not widely used in Croatia. In cropland farming, legumes as a main or cover crop can store 30% more organic C in the soil compared to other species [64] but also fix nitrogen. Legumes in grassland increase the C content of the soil by improving biomass productivity and biodiversity [65], while legumes in pastures improve the quality of topsoil organic matter and increase the degree of humification [66].

Optimizing the management of cropland and grassland with legumes is of crucial importance for C sequestration. Stipesevic et al. [27] introduced legumes into croplands and increased dry matter and yields of current and subsequent crops, proving that legume-enriched organic C can reach a new equilibrium after a few years. In grassland, legumes also increase the digestibility and nutritional value of the forage [67]. As far as the author is aware, legumes are not used under Croatian climatic and pedological conditions. Legumes should be tested in humid areas with good rainfall distribution—primarily in Pannonian Croatia, on grassland in Adriatic Croatia, in Licko-Senjska and Primorsko-Goranska counties, and in the interior and northern part of Istria county. In these areas, legumes should be cultivated as cover crops.

7.2. Introducing and Optimizing Fertilization Practice

Fertilization as a possible measure to increase C sequestration includes cropland and grassland. Nitrogen fertilization has several effects on organic C. First, it promotes the growth of aboveground and belowground biomass and increases soil organic C [28,29,68], and on the other hand, it can promote mineralization and decrease soil organic C [69]. Therefore, it is necessary to optimize nitrogen fertilization, even more so when it is known that plants develop more belowground growth under limited nutrient conditions in order to maintain nutrient uptake [68]. Dosage and type of fertilizers should be tested on different soils in Croatia to identify appropriate practices that support belowground and aboveground biomass formation and increase organic C. When fertilizing, it is necessary to know the needs of the soil and the crop, as contradictory results on the influence of fertilization on C sequestration in grassland have shown that fertilization must be adapted to the climatic conditions, soil, and phytocenoses on the grassland [70]. Fertilization with manure also increases belowground and aboveground biomass [29,30,31] and C storage. However, the effect of direct C addition by manure should also be considered here. In general, C fixation in the soil and fertilization also depend on the annual precipitation, the average annual temperature, and the type of vegetation. This should be considered when promoting and establishing regulations for sustainable grassland management in Croatia. Current findings in Croatia indicate that improved fertilization can be introduced nationwide.

7.3. Introduction of Integrated Farming and Livestock Management Systems into Practice

Integrated farms have a positive effect on cropland and grassland, as the introduction of forage crops (grass mixtures, clover, clover-grass mixtures) and grazing on specialized crop farms increases C sequestration [22]. Furthermore, the introduction of perennial forage crops in the crop rotation, e.g., alfalfa, would have several positive effects on the environment. Perennial plant cover and dense structure reduce erosion and loss of C, as well as other elements [35]. Perennial plants, especially legumes, reduce nitrogen leaching and fix nitrogen in the soil, which the plants use for higher vegetative growth, and thus, greater C accumulation [71]. Perennial legumes and clover-grass reduce possible organic C losses due to the omission of tillage and the reduction of the use of mechanization. In mixed farming systems, losses during the manure application are reduced [22].

Integration need not be done only on one farm but can also be organized on several farms in the vicinity. With this proposal, the greatest resistance in Croatia is due to lack of knowledge, motivation, and resources of the farmers. In parallel to the conversion of crop rotation, the introduction of grazing on cropland is a promising alternative. Conversion from intensively farmed croplands to pasture would lead to C sequestration [33], although Croatian farmers do not practice conversion on a large scale.

7.4. Agroforestry

In Croatia, farmers are showing increasing interest in planting orchards on arable land [72], which contributes to the sequestration of C. In addition, grazing systems involving natural resources such as pastures and oak forests have been known in Croatia and surrounding countries for centuries [17,73]. International work has shown an increase in C after transition from cropland [74] or grassland [75] to agroforestry systems, especially when tree diversity is high [76], but Croatian experience is lacking. The full effect of agroforestry management may only be realized after several decades. Therefore, a long-term approach to monitoring this type of land management is needed to recommend an ideal practice. Regardless of the long-term nature, the positive effect of agroforestry on C sequestration is already recognized worldwide, and this practice can be recommended for wider adoption under all climatic and pedological conditions in Croatia.

7.5. Optimizing the Method and Intensity of Grazing

The problem of overgrazing is low and sporadic in Croatia due to the drastic decline of livestock numbers over the last decade and lower grazing pressure compared to the EU [33]. Nevertheless, grazing should be considered as a possible practice for more efficient C sequestration. Heavy grazing leads to trampling and soil compaction, reduces the mass of plants capable of photosynthesis, and reduces the possibility of accumulating belowground biomass [26]. Rotational grazing has a better effect on C sequestration and results in greater aboveground biomass, uniform grazing load, less soil erosion, and better animal productivity than continuous grazing [77,78]. Rotational grazing should be promoted in Pannonian Croatia (continental climate) on farms with medium and higher grazing intensities. Under the climatic conditions of Mediterranean (Adriatic) Croatia, rotational grazing is of less importance, mainly because of the low animal load on pastures due to the number of conditional heads, but also because of free grazing on other natural pastures such as forests, maquis, and garrigue [57].

7.6. Application of Conservation Tillage, Diverse Crop Rotations, and Cover Crops

Tillage influences soil C both by building it up (e.g., humification of crop residues and other biomass, increasing the stable organic C content, binding organic C by forming organo-mineral complexes, and increasing the stability of aggregates) and by breaking it down (e.g., mineralization, erosion, leaching). The term conservation tillage refers to a range of practices that reduce soil and water losses compared to conventional tillage and retain mulch on the topsoil [79]. The positive effects of conservation tillage on soil organic C content have been confirmed in Croatian croplands [12,80,81].

Conservation tillage has been put into practice in Croatia in the last decade [81]. Its most radical variant (no-tillage) has yet to be established, although there are certainly possibilities for it. Even on soils with natural limitations, of which there are many in Croatia, other forms of conservation tillage, such as minimum or reduced tillage, certainly have a more positive effect on C storage than conventional tillage with plow and disk harrow [12,40]. Conservation tillage stores significant amounts of organic C on cropland, which is saved from emissions to the atmosphere and helps Croatia meet its climate policy commitments [52].

Diversified balanced crop rotations and an even proportion of grass, legumes, forage crops, and minor crops can be a crucial factor in increasing C stocks by improving biomass production and C sequestration [22,32,82]. Cover crops play a similar role but are not widely practiced in Croatia, although the usual two-field maize–wheat rotation has resulted in bare soil for more than 6 months. Moreover, cover crops increase biomass and biomass of residues that improve soil C sequestration [27,49], especially if the cover crops are legumes. The cultivation of cover crops should be promoted in Croatia and, at the same time, included in crop rotations.

8. Conclusions and Policy Recommendations

To ensure competitiveness, sustainability, and self-sufficiency, Croatian agriculture must urgently address legislative, administrative, market, and research shortcomings across all stakeholder levels. The adoption of carbon farming, alignment with EU climate policies, and recent geopolitical pressures make this transition a high priority.

Conventional agriculture dominates in Croatia, but management practices on most croplands and grasslands are unsuitable for carbon sequestration and contribute to soil degradation. This represents both a challenge and an opportunity, as these systems hold substantial capacity for carbon storage. Management decisions must account for differences in soil type, suitability, and climatic conditions. The following recommendations result from this review of the current situation and the legal framework in Croatia on cropland and grassland:

• Promote conservation tillage through targeted direct payments, prioritizing fertile soils and supporting transitional periods until a new equilibrium is reached.
• Strengthen organic farming by linking subsidies to active agro-technical measures that improve yields, soil fertility, and carbon storage.
• Adopt climate-positive practices such as agroforestry, legume cultivation, continuous greening of perennial crops, conservation tillage, silvopastoral systems and rotational grazing, and robust protection of permanent grasslands.
• Optimize fertilization by applying organic and mineral fertilizers only after site-specific trials, prioritizing humid areas first.
• Encourage integrated farming systems by connecting crop and livestock production units locally to enhance self-sufficiency.
• Expand perennial forage crops and legume cover into crop rotations, inter-row spaces in perennial croplands, and managed grasslands, starting in humid regions.
• Recognize agroforestry in legislation and incentivize tree planting for biodiversity and multiple ecosystem services.
• Promote rotational grazing in livestock farming. Research is not required, and the measures can be implemented immediately throughout Croatia.