Striga hermonthica, a parasitic weed, has long been believed to be correlated with the declining soil fertility status. However scientists have recently come to question this statement since some recent studies have shown contradictive results. To investigate whether soil fertility status and infestation of Striga hermonthica were correlated and the impact of it were caused by farmer management, 120 farmers in Western Kenya, where Striga hermonthica infestation is prone, participated in this study. In three districts with two sub-locations each, farmers answered a structural questionnaire and identified two fields, one with high and one with low soil fertility. These fields later came to be the basis for this study and soil were therefore also sampled from them.

Calcareous fens constitute a specific habitat which is uncommon in Europe and protected by the EU habitat directive due to its importance to several threatened species. Hagebyhöga in Östergötland is a calcareous fen habitat included in the Natura 2000 Networking Programme. Adjacent to the existing fen, a degraded fen area is situated. The area has been used for agriculture for several years but is now going to be restored to its former state by the county administrative board of Östergötland.When working with restoration of degraded fen areas it is important to aquire knowledge about the chemical soil conditions. Plant growth limited by phosphorus and low fertility are characteristic conditions for calcareous fens, whilst arable land usually is highly fertile and limited by nitrogen.The purpose of this study is to bring forth useful knowledge for restoring the degraded calcareous fen of Hagebyhöga.

Hunger is a problem in some parts of the world (www, FAO 1, 2012). The lack of food is often a result of insufficient knowledge in Soil fertility management (Röing de Nowina, 2012). Ongoing hunger and malnourishment are quite prevalent in Sub-Saharan Africa and are often combined with poverty (www, FAO 1, 2012). Farming is the most common occupation in this area and the farms are often small-scale farms with subsistence crops and a few cattle. The farmers who operate these small-scale farms are economically a weak group.

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Smallholder farmers in Uganda suffer from declining productivity. With a rapidly increasing population, marginal land is taken into production and the current land management leads to loss in soil fertility and escalation in soil erosion. There are studies indicating that the use of agroforestry increases soil organic carbon (SOC) compared to systems without trees. Soils which are high in carbon have many advantages, for example better water holding capacity, which can reduce stress on crops during drought. The aim of this study was to determine the effect agroforestry has on SOC concentration in small-holder farming systems in Uganda. The intended system to study was farms practicing agroforestry methods or not in intercropped plantain (cooking banana) fields.

The soil acidification and the pH-value of the soil have been discussed for many years. Many observations of the tree species effects on the soil pH have been done. We have discussed the effects on the soil surface pH-value with a birch (Betula spp. L.) admixture in Norway spruce stands (Picea abies L.).We have used data from the Swedish National Forest Inventory. We have also discussed how the wood production and the biodiversity can be increased in mixed stands, in according to the Swedish forestry act Skogsvårdslagen. Our sampling areas are located in Norrland, Sweden. The results show a significant correlation between an increased birch admixture and an increased pH-value of the soil.

Agriculture has to be performed in a sustainable way in order to sustain high yields and to support a globally growing population. Functional soil properties are fundamental for high yields and in order to achieve good soil conditions sustainable management is a key. Loss of soil organic material and increased soil acidity are problems associated with degradation of soils and hence less sustainable agriculture. In this thesis, the effect of different agricultural systems on soil organic matter, pH and yield was examined. The systems examined are a cereal system with straw removal or returning and a ley system, all with different nitrogen levels.

During the last decades the fertility of dairy cows has declined in the same rate as the milk yield has increased. This is a result of the negative genetic correlation between milk yield and fertility, failure to show estrous signs and metabolic problems in the cow. The purpose of this review was to investigate the function of metabolites and hormones as markers for disturbances in fertility, health and production in the dairy cow. There are several metabolites that are suggested to indicate the cow?s energy balance.

The aim of this literature review was to suggest suitable index traits to use in the Swedish Sheep Recording Scheme for fertility and maternal traits. Since fertility and some of the maternal traits are not normally distributed advanced methodology is needed to calculate genetic parameters. Breeding is a tool to improve the economy of the farm and for the selection of breeders estimated breeding values (EBV) for important traits are of high value. In sheep breeding both lambs born and lambs weaned should be taken into consideration as well as the ewe?s maternal ability, which includes lambing ease, lamb survival, ewe behaviour as mother and the early growth of the lambs.

To get a good economy on the dairy farms the fertility control of heifers and cows is a crucial factor. It is also important to know which key parameters that should be tracked. In this work well established routines for heat detection have to be applied. When the dairy farmers use technical aid in estrus control it is important not to forget that technical aids can not replace the human eye. Approximately 50 % of all opportunities to inseminate are missed because clear signs of estrus have not been displayed and/or recorded. The cattle fertility has been declining over recent years. During the same time the cow?s proceeds have increased, consequently applying a higher pressure on the cow and the manager.

The fertility of dairy cows is of great importance in order to maintain high production. The decline in fertility of dairy cows the latest decades can have several explanations. The large emphasis on high yielding cows and the negative genetic correlation between milk production and fertility traits could be one of the main factors for impaired fertility. To find heats and inseminate the cow at the right time is crucial to receive high conception rate. Delaval has, in corporation with FOSS, developed Herd Navigator which is a management program that measure four biological parameters in the milk; progesterone, betahydroxybutyrate, lactate dehydrogenase and urea.

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.

The impact of the distribution in the soil volume of two farm manures on the net mineralization and immobilization processes of nitrogen were studied in an incubation experiment. Cattle slurry and broiler litter were placed in the soil with three procedures for incorporation including placement on top of the soil (TOP), in the middle of the soil (MID) and mixed homogenously with the soil (MIX). During the two weeks of incubation, few significant differences in net mineralization were seen between TOP, MID and MIX. However, there was a tendency that MIX led to a larger net immobilization of N than placement at one point (TOP and MID). This is also the result in the literature.

Variations in fertility have caused a problematic situation in Sweden among other European countries. According to the Council of Europe we are facing an economic and demographic challenge, when the baby boomers of the 1940?s are retiring. Economists have for a long time studied the connection between economic factors and fertility, and several studies have found a correlation between business cycles and birth rates. This connection is again of current interest 2008, when a financial bubble bursts at the same time as a baby boom occurs.

Variations in fertility have caused a problematic situation in Sweden among other European countries. According to the Council of Europe we are facing an economic and demographic challenge, when the baby boomers of the 1940?s are retiring. Economists have for a long time studied the connection between economic factors and fertility, and several studies have found a correlation between business cycles and birth rates. This connection is again of current interest 2008, when a financial bubble bursts at the same time as a baby boom occurs.