Theoretical part of the diploma thesis (review) is focused on historical development of the Common Agricultural Policy (reforms from the years 1999 and 2003 are emphasized) and on the comparison of the agri-environment schemes (AES) of the Czech Republic, Slovak Republic, and Austria. The aim of the review was to summarize the processes, which led to the recent form of AES. In practical part of the thesis measures, which support maintaining and increasing of populations of ground game and birdlife, i.e. measures Catch Crops, Rich Seed Habitat (Biobelt), and Bird Area on Grasslands were evaluated. Data from Paying Agency SZIF were used. The study covers both, the (shortened) programming period 2004-2006 and the programming period 2007 {--} 2013 (years 2004 {--} 2008). Thesis is focused on region NUTS II Southeast. The following indicators were analysed: interest of the farmers in the selected AES measures, area on which the measures were carried out and amount of the financial support spent to support individual measures. Finally, steps to optimize the use of financial resources are suggested. Catch Crops are used as a measure on arable land. The highest interest of the farmers in Catch Crops was observed in the year 2004, when the largest number of the farmers entered this measure. The interest was decreasing in the following years (especially in the years 2007 and 2008, when the endowment was lowered). Catch Crops cover 6 {--} 8 % of the arable land of the region and the area has been increasing in time. Biobelt is only sporadically used measure (probably because of the underestimation of the costs), but interest in it (albeit low) has been increasing during the whole period. Measure Bird Area on Grasslands is restricted to nesting areas of Corncrake (Crex crex) and Waders (Charadrii). In NUTS III South Bohemian Region, the measure was applied on approximately 27 % of the area where it potentially can be used during the whole observed period. In NUTS III Plzeň Region, the area increased from 26% in the years 2004 {--} 2006 to 60 % in the years 2007 and 2008.

MSCAGR (Soil Science) / Department of Soil Science / Maize (Zea mays L.) is widely grown in the semi-arid regions of South Africa mainly for its grain that is used for direct human consumption, feed for animals and raw materials for the industries. The challenges of soil infertility, water supply, and availability of high yielding cultivars remain a major constraint for its production in this environment. These constraints are a major threat to sustainable crop production and food security. Maize/lablab Zea mays L.\ L. purpureus) intercropping system could thus become an option for food security among small scale maize producers in dry environments. Preliminary studies show the huge potential of maize/lablab intercropping in the semi-arid environments of the North-Eastern South Africa. Therefore, this study aimed to assess the effects of maize/lablab intercropping on soil water content, nitrogen dynamics and crop productivity based field experiments and crop simulation modeling using the model APSIM. The trials were conducted at two sites (Univen and Syferkuil) in Limpopo province, South Africa, for two seasons (2015/2016) and 2016/2017). The treatments consisted of; (i) sole maize (ii) sole lablab (iii) maize and lablab planted at the same time (Maize+lablab-ST) and (iv) maize with lablab planted 28 days after maize (Maize+lablab-28).The treatments were laid out in an RCBD replicated 4 times, with individual plots size measuring 4.5 m × 4 m (18 m2) and the layout of the field as consisting of 4 plots per block giving a total of 16 plots in 4 blocks. The following parameters were determined: soil water content, soil NO3--N and NH4+-N levels, dry matter and grain yield. The APSIM-model (version 7.7) was then used to simulate maize grain yield and dry matter production to assess risks associated with the production of maize/lablab intercropping. The results obtained from this study showed that maize/lablab intercropping had significant effects on measured parameters (grain, biomass yield soil water content, and N-minerals). Maize+lablab-28 produced 46 % higher grain yield than sole cropping (24%) and maize+lablab-ST) (30%). The results also showed variation in soil water content at different depths among the treatments. The soil water content was increased with depth. The intercropped plots and lablab sole had significantly higher soil water content than the sole maize. At all depths, the highest soil water content was obtained under sole lablab followed by maize+lablab-ST and maize+lablab-28. It was notable however that maize/lablab intercropping showed a higher NO3--N and NH4+-N levels at all depths. At both sites, the soil NO3--N showed a sharp drop at V7 sampling time. The results showed the benefits of intercropping in comparison to sole cropping as demonstrated by positive land equivalent ratios of >1 for both cropping systems in both years and sites. Modelling exercises showed that APSIM was able to simulate the results sufficiently. In the simulation experiment, a stronger negative effect of planting lablab with maize simultaneously was found. Hence, delayed planting of lablab should be a standard practice / NRF

1. Ištirti skirtingo humusingumo glėjiškame rudžemyje alternatyviose intensyviajai žemdirbystės sistemose su daugiamečių žolių atolu ir tarpinių pasėlių biomase į dirvožemį įterptų biogeninių elementų kiekį ir jų poveikį sėjomainos augalų produktyvumui. 2. Įvertinti su trąšomis įterptų ir su derliumi prarastų biogeninių elementų NPK balansą ekologinės bei tausojamosios žemdirbystės sistemose ir nustatyti judriųjų fosforo ir kalio pokyčius dirvožemyje. 3. Nustatyti tausojamosios ir ekologinės žemdirbystės sistemose tarpiniuose pasėliuose augintų augalų biomasėje sukaupto azoto poveikį Nmin. dinamikai dirvožemyje. 4. Ištirti naudotų trąšų ir tarpinių pasėlių poveikį humuso ir jo sudėties pokyčiams ekologinės bei tausojamosios žemdirbystės sistemose. 5. Įvertinti ekologinės ir tausojamosios žemdirbystės sistemose naudotų agropriemonių poveikį pagrindinių dirvožemio fizikinių rodiklių stabilumui, agrofitocenozių dominantėms ir augaluose sukauptai bendrajai energijai. / 1. In the cropping systems alternative to the intensive cropping system, set up on a gleyic Cambisol with a different humus status, perennial grasses and biomass of catch crops are a significant reserve of biogenic elements for the productivity of crop rotation plants. 2. In the organic and sustainable cropping systems, farmyard manure and biogenic elements incorporated with it have a greater positive effect on the NPK balance and changes in available phosphorus and potassium in the soil compared with green manure. 3. Catch crops are important from the environmental viewpoint, since by accumulating nitrogen in their biomass they reduce Nmin. concentration in the soil and become a reserve of nutrients for succeeding plants. 4. In the soil with a different humus status, alternative cropping systems have a diverse effect on humus stability and changes in its quality. 5. In the sustainable and organic cropping systems, catch crops and their biomass play an important role for soil physical parameters, agrophytocenoses dominants and total energy.

MENVSC / Department of Ecology and Resource Management / The study investigated the impact of cover crops (Medicago sativa, Lotus corniculatus, Trifolium pratense, Melilotus alba and Phacelia tanacetifolia), bare soil and natural ground cover on pest and beneficial arthropods, soil health, crop yield, pest damage and weed suppression in avocado orchards. The trial plots were sited within established commercial avocado orchards with trees of similar cultivar (‘Hass’), soil-type and age, located in Levubu, Limpopo, South Africa. Mixtures of cover crops were planted in the alleys of avocado orchards and the effects were compared to that of a control (other half of the orchard). Mechanical clearing of vegetation in half of the alleys of different avocado orchards were compared to the other half that was left undisturbed. Data were collected during the flowering and fruit set stages of the avocado trees in the months of September - November 2019. Results revealed that there was higher abundance and diversity of flowering plants in the orchard alleys of the cover crop treatment compared to the control comprising of natural vegetation. Cover crops had a significantly positive effect on the soil health of the orchard but little or no effect on beneficial arthropods within the orchard nor any positive effect on the pests of avocados. However, the number of thrips scouted on the fruit were significantly less where cover crops were established. Avocado scale infection rates were also significantly lower where cover crops were established. There were significantly less arthropods, and specifically pests, pollinators and herbivores where the topsoil was removed mechanically. The yield resulting from the orchard half where cover crops were established were significantly higher. More research still needs to be done about the use, management and impact of cover cropping on not only commercial avocado orchards but on other fruit crops. This study shows good evidence for the benefits for using cover crops and the negative effects in having no vegetation cover in the orchards. / NRF