Apesar de o manejo da pastagem ser um componente chave em sistemas pastoris, poucos esforços foram feitos para determinar a intensidade de pastejo adequada para pastagens tropicais, especialmente sob condições irrigadas. O atrativo econômico de sistemas de pastagens irrigadas depende da elevada produtividade da pastagem, o que significa que fertilizantes nitrogenados precisam ser utilizados. Entretanto, para estabelecer medidas efetivas visando o manejo do nitrogênio (N) é necessário entender o balanço entre entradas e saídas de N e a eficiência de ciclagem e transformações do N em sistemas de produção animal em pastejo. Nesse contexto, sete experimentos foram realizados para avaliar o efeito do resíduo pós-pastejo ou de níveis de fertilizante nitrogenado sobre a produção de forragem e a recuperação do N-fertilizante em pastagem irrigada de Panicum maximum cv. Tanzânia. O resíduo pós-pastejo para pastagem de capim Tanzânia irrigada e adubada com N durante o inverno, considerando ciclo de pastejo de 36 dias, deve ser de aproximadamente 1.900 a 2.100 kg/ha de massa seca verde. Para as estações de primavera e verão, a massa de forragem residual deve ser de cerca de 1.700 a 2.700 kg/ha de massa seca verde. Esse manejo assegurou que a produção de folhas e a relação folha/haste fossem próximas do máximo. Parcelas de 1 m 2 , tendo uma touceira do capim em seu centro geométrico, foram adequadas para estudar a recuperação de fertilizante- 15 N, independentemente da intensidade de pastejo e estação do ano. O aumento da intensidade de pastejo resultou em decréscimo na massa da touceira. Quanto menor a massa da touceira, maior a dependência no N-fertilizante. A combinação de elevada umidade do solo, ausência de chuva no dia subseqüente à adubação e alta temperatura determinaram baixa recuperação de 15 N-uréia no sistema solo-planta (< 35% do N aplicado) e elevadas perdas de amônia por volatilização (> 40% do N aplicado) nos níveis de adubação superiores a 80 kg/ha de N durante o verão. A absorção foliar da amônia volatilizada da uréia aplicada ao solo variou de 2,5% (120 kg/ha de N) a 16,4% (40 kg/ha de N) do nitrogênio volatilizado. Com adubações inferiores a 60 kg/ha de N observou-se níveis subótimos de nutrição nitrogenada e tendência de maior discriminação do 13 C durante o verão. / Whilst grazing management is a key component in pastoral systems little effort has been made to determine the adequate grazing intensity for tropical pastures, especially under irrigated conditions. The economical attractiveness of irrigated pasture systems depends on high pasture productivity, meaning that fertilizer nitrogen (N) must be used. However, to make effective changes toward sustainable N management, an understanding of the balance between N inputs and outputs and the efficiency of N cycling and transformation within the grassland system is required. In this context, seven experiments were carried out to evaluate the effect of post-grazing residue or nitrogenous fertilizer levels on herbage production and on fertilizer-N recovery in irrigated Panicum maximum cv. Tanzania pasture. The post-grazing residue for irrigated, N-fertilized Tanzania grass pasture during the winter, considering a 36-day grazing cycle, should be around 1900 to 2100 kg/ha of green dry matter. During the spring/summer seasons the residual stubble mass should be around 1700 to 2700 kg/ha of green dry matter. This management ensured that leaf production and leaf/stem ratio were close to the maximum. A plot-size of 1 m 2 , with a tussock of the grass in its geometric center, was adequate to study 15 N-fertilizer recovery irrespective of grazing intensity and season of the year. Increasing the grazing intensity resulted in decreased tussock mass. The smaller the tussock mass the greater was the reliance on fertilizer-N. The combination of high soil water content, lack of rainfall in the day following fertilization and high temperature determined low urea- 15 N recovery in the soil-plant system (< 35% of applied N) and high ammonia volatilization losses (> 40% of applied N) at fertilizations levels higher than 80 kg N/ha during the summer. The absorption of ammonia volatilized from urea applied to soil varied from 2.5% (120 kg N/ha) to 16.4% (40 kg N/ha) of the volatilized nitrogen. With fertilizations lower than 60 kg N/ha it was observed sub-optimal N nutrition and a trend of higher 13 C discrimination during the summer.

O mundo atual passa por uma revolução na produção industrial de animais, busca-se atender as exigências do mercado focando na qualidade do produto final e nos sistemas de produção. A partir da preocupação pública com a melhoria do bemestar de animais de produção e o maior controle da cadeia produtiva, protocolos internacionais com recomendações de boas práticas de produção foram desenvolvidos, a fim de simplificar e esclarecer os princípios de bem-estar animal (BEA) para o setor produtivo. No Brasil, os sistemas existentes e as pesquisas direcionadas ainda estão na fase de avaliar os gargalos tecnológicos, oriundos de sistemas de produção com diferenças em relação às escalas de produção. Nesse contexto, há a necessidade de avaliar cada sistema brasileiro de produção, suas particularidades e comparar aos sistemas europeus e americanos. O Brasil é um país de destaque na produção de proteína animal, e deve estabelecer suas próprias condições de qualidade frente à sua escala e a suas particularidades de produção. Não há como simplesmente aderir às exigências internacionais, sem atentar para a realidade nacional seja ela de produção, de nível tecnológico e de exigências/dificuldades dos produtores rurais. Baseando-se na necessidade do estabelecimento de padrões para o sistema brasileiro de produção de leite em pasto, conforme Instrução Normativa 56/2008, do Ministério da Agricultura Pecuária e Abastecimento (MAPA), esse estudo propôs uma adaptação do sistema de avaliação do protocolo Welfare Quality® Assessment protocol for cattle - applied to dairy cows (2009) para avaliação do bem-estar de vacas leiteiras em sistema de pastejo. A aplicação do protocolo Welfare Quality adaptado para o sistema de pastejo possibilitou a avaliação e a classificação de forma quantitativa e qualitativa em relação ao bem-estar geral do rebanho, e consequentemente da propriedade leiteira. / The current world is going through a revolution in the industrial livestock production, so it is important to meet market demands by focusing on product quality and farming systems. Based on public concern regarding farm animal welfare improvement and greater control of the productive chain, international protocols with good production practices recommendations were developed in order to simplify and clarify animal welfare principles to the productive sector. In Brazil, the existing systems and targeted researches are still at the stage of assessing technologic bottlenecks, arising from production systems with differences related to production scales. In this context, there is a need to assess each Brazilian production system, their peculiarities and to compare European and American systems. Brazil is a country of prominence in animal protein production and shall establish its own quality conditions ahead of its scale and its production particularities. There is no simply meeting international requirements without considering the national reality of production, technological level and farmers\' demands/difficulties. Relying on the need to establish standards for Brazilian system of milk production in pasture, according to Normative Instruction n° 56/2008, from the Ministry of Agriculture, Livestock and Supply (MAPA), the present paper proposed an adapted evaluation system from Welfare Quality Protocol® -Assessment protocol for cattle - applied to dairy cows (2009) to assess the welfare of dairy cows raised in pasture. The implementation of the WQ adapted protocol allowed the evaluation and classification of the farms quantitative and qualitatively in relation to general animal welfare, and consequently the production facility.

Orientador: Mauro Galetti Rodrigues / Resumo: A conversão de paisagens florestais para usos antrópicos é a principal causa do desmatamento das florestas tropicais em todo o mundo. Essas florestas são conhecidas por conter parte significativa da biodiversidade terrestre global, porém pouco se sabe sobre como as modificações na paisagem, como a perda de habitat para produção agropecuária e o principalmente o impacto do gado afetam a diversidade e ocupação de mamíferos resilientes nesses fragmentos. Sendo assim, nós examinamos como a riqueza de espécies e a composição de mamíferos são explicadas pela configuração da paisagem e como a presença do gado afeta a detecção de mamíferos de médio e grande porte. Foram amostradas 20 paisagens dominadas por pastagens ao longo de um gradiente de cobertura florestal (8% a 98%), no sudeste do Brasil. Nós registramos 75% das espécies de mamíferos esperadas para esta região em uma cobertura florestal de média a alta. A cobertura florestal, distância euclidiana do vizinho mais próximo e área estrutural foram as variáveis que melhor explicaram a ocorrência de algumas espécies de mamíferos dependentes de floresta. As comunidades de mamíferos exibiram um alto grau de alternação de espécies entre as paisagens, representando 95% da diversidade beta total. Os impactos da pecuária foram mostrados devido ao seu efeito negativo na detecção de espécies florestais e positivo na detecção de grupos de espécies não florestais. Discutimos a importância de manter fragmentos com alta cobertura vegetal para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The landscape conversion to anthropic uses is the major cause of deforestation worldwide. Tropical forests are known to contain a significant portion of global terrestrial biodiversity, but little is known about how changes in landscape, such as habitat loss for livestock and its impacts affect the diversity and occupation of resilient mammals in forest fragments immersed in pasture matrices. Here we examine how species richness and mammal composition are explained by landscape configuration and how cattle presence affects the detection of medium and large mammals. We sampled 20 landscapes dominated by pastures along a forest cover gradient (8% to 98%) in southeastern Brazil. We recorded 75% of the mammalian species expected for this region in a medium-to-high forest cover. Landscapes metrics, as forest cover, Euclidean distance from the nearest neighbor and structural area were the variables that best explained the occurrence of some forest mammal species. Mammalian communities exhibited a high degree of species turnover between landscapes, representing 95% of total beta diversity. Livestock impacts were shown due to its negative effect on the detection of forest-dwelling species and positive on the detection of non-forest species groups. We discuss the importance of maintaining forest fragments with high vegetation cover to improve connectivity between disturbed landscapes, favoring mammalian species flow. There is an urgent need for a better understanding of livestock gene... (Complete abstract click electronic access below) / Mestre

Soil organic matter is important as storage for carbon and nutrients, supporting soil structure, and as a filter for pollutants entering the soil ecosystem. The recovery of soil organic matter in depleted soils can take decades, or even hundreds of years. It has been assumed that in non-eroding pasture, soil carbon levels either increase or not change over time. However, some recent studies have suggested that fertiliser addition to pasture soils may contribute to decreases in soil carbon content. My hypotheses were: 1. As P fertiliser loadings increase the soil carbon content and C:N ratio will decrease. 2. Changes in C pools will be greater in the more active pool (readily available carbon, and microbial biomass carbon) within the soil total carbon The study was undertaken at a long term fertiliser trial, established in 1980, at the Whatawhata Hill Country Research Station west of Hamilton, New Zealand. The fertiliser trial has P fertiliser application rates maintained since 1984. Olsen P, total C, total N, labile carbon, respirable carbon, specific respiration rate, microbial biomass C, microbial quotient, mineralised N, microbial biomass N, microbial N quotient, and mineralised N per microbial biomass nitrogen, C:N ratio, and soil pH were measured on soil samples collected from 12 paddocks with six P fertiliser loading (0, 10, 20, 30, 50, 100 kg P ha-1 yr-1). As expected, the available P (Olsen P) increased significantly (P less than 0.001) with increasing P fertiliser application rate. Total carbon, labile carbon, and total nitrogen all decreased significantly (P less than 0.05) with increasing P fertiliser application. No significant relationships were found between P fertiliser and respirable carbon, microbial carbon, microbial (C) quotient, microbial specific respiration, microbial nitrogen, microbial (N) quotient, mineralised N, or C:N ratio. The first hypothesis was rejected as the C:N ratio did not change with increased P fertiliser application. However, both C and N decreased with increased P fertiliser application. The second hypothesis was, therefore, accepted in part because there was a decrease in labile carbon (readily available carbon) and total carbon, with P fertiliser application, but no relationship was evident for the respirable carbon and microbial biomass.

Leafy vegetables, lettuce (Lactuca sativa L. cv. Green Oakleaf), pak choi (Brassica sinensis L. cv. Oriental Taisai) and rocket (Eruca sativa L.), were planted in an open field at Lincoln University on January 2005. Plants were harvested at 5 cm cutting height above the growing point with three different harvest start times, early start (ES), mid start (MS) and late start (LS) of harvest respectively. There were three harvests during the growing season with a 4-week interval between harvests. Generally, lettuce produced significantly higher total FW/plant (208 g) than pak choi or rocket (123 and 102 g total FW/plant, respectively). Lettuce also produced significantly higher total FW/plant than pak choi or rocket in each treatment. Lettuce produced significantly more total saleable leaf FW/plant in the ES, MS and LS treatment (137.5, 120.9 and 169.3 g FW/plant), compared with pak choi (52.9, 100 and 92 g FW/plant) or rocket (31.5, 92.2 and 56.4 g FW/plant). Pak choi produced higher total saleable leaf FW/plant than rocket in the ES and LS treatments, but a similar total saleable leaf FW/plant in the MS treatment. The best time to start harvesting was the LS treatment for lettuce, while pak choi and rocket produced better yields in the MS and LS treatments. Results for total DW/plant showed that different harvest start times did not affect the total DW/plant in lettuce. However, pak choi and rocket produced less total DW/plant in the ES treatment compared to the MS or LS treatments. This was due to a faster recovery by lettuce. In addition, lettuce produced significantly higher DW/plant during regrowth at the second and third harvests than pak choi or rocket, even though it was significantly lower at the first harvest. It is likely that after harvesting greater carbohydrate reserves and greater remaining leaf area produced greater regrowth potential in lettuce. These results suggest that lettuce has the most regrowth potential, while rocket has more than pak choi in this reaping and regrowth system. When plants were harvested at the same cutting level, lettuce had the most remaining leaf area of the three species. This remaining leaf area for lettuce could be another reason for faster recovery and more regrowth potential. More reserves and remaining leaf area may also be the reason for more regrowth potential in rocket compared to pak choi. Another important reason for the better performance of lettuce was that temperatures during the growing season were in the range of optimum temperatures (12-21 ºС), except for the regrowth between the second and third harvests in the LS. This relates to higher photosynthetic rates and in turn leads to faster recovery and regrwoth. Lettuce was the most suitable crop in the reaping and regrowth system in this experiment. However, rocket might also be appropriate for this system, particularly if the price is high enough to make it economically viable.

This thesis describes a series of four experiments designed to evaluate the role of the supply of protein in livestock grazing high quality pasture during mating and during pregnancy. The first two studies investigated the effects of high crude protein content of spring or autumn re-growth pasture on the reproductive performance of dairy cows and of ewes at mating. The last two studies investigated how the dietary supply of protein, body condition and their interactions contribute to the breakdown of immunity during the peri-parturient period in ewes and investigated underlying endocrine mechanisms. In the first study (Chapter 3) cows were blood sampled via the tail vein during the breeding period in spring. Plasma was then analysed for urea concentration. Cows with high plasma urea (HPU) or low plasma urea (LPU) were defined as those with plasma urea concentrations of ≥ or < 44.9 mg/dl respectively. Lactating cows (n = 200) were also categorized into high milk producers (HMP) or low milk producers (LPM) relative to an average daily yield of 26.6 l/d. Pasture clipping showed an average pasture CP (crude protein) content of 223 g/kg DM. Concentrations of plasma urea ranged from 26.6 to 64.4 mg/dl. No correlation was observed between plasma urea concentration and either reproductive indicators or milk parameters. Mean blood urea concentration of HPU cows was 50.8 compared to 38.5 mg/dl in LPU cows. There was a trend for more animals (P = 0.09) in the HPU group than in the LPU group not to return to oestrus. Cumulative pregnancy rate in HPU and LPU was similar except at week 6 after the start of mating when more (P < 0.01) HPU than LPU cows were pregnant. Calving to conception interval, calving interval and interval between conception and first service were similar (P > 0.05) between HPU and LPU cows. Gestation length, calving rate, milk yield and milk components were also similar (P > 0.05) between LPU and HPU cows. There was no difference (P > 0.05) in plasma urea concentrations between HMP and LMP milk producers. However, calving to conception interval, interval between calving and first service and calving interval were longer (P < 0.001), submission rate higher (P < 0.001) and NRR (Non-return rate) higher (P < 0.05) in LMP than HMP. The number of services, the interval between first and second service, gestation length and CR (calving rate) were similar (P > 0.05) between HMP and LMP cows. HMP had lower (P < 0.001) milk protein and fat concentrations than LMP cows. This information indicates that, despite the fact that plasma urea was consistently higher than levels in the literature which have been associated with reduced fertility in dairy cows; no impairment of reproductive performance was observed. In the second experiment (Chapter 4) mature and dry Coopworth ewes were blocked by weight, body condition and previous prolificacy (high, HP vs low twinning frequency, LP) into two groups and thereafter randomly allocated to diet which were designed to provided either 1) high protein (163 g/kg DM, ryegrass/red clover pasture, HPP) or low protein (119 g/kg DM, hay and barley grain, HB) supply at joining. These were designed to provide high and low plasma urea concentration. Over a period of 17 days, ewes recorded as mated were examined by laparoscopy, at which time there was no difference in blood urea concentration (58.6 vs 56.1 mg/dl) between HPP and HB groups. Fifty days after the start of joining the number of foetuses present was counted using ultrasonography. As a consequence of lack of difference in the plasma urea concentration, irrespective of treatment group, individual animals were categorized into high (HU) and low plasma urea (LU) status based on whether plasma urea concentration was higher or lower than the sample mean of 51.5 mg urea/dl. Lambs which weighed greater than the mean plus one standard deviation for their litter size were classified as oversize. Ovulation rate and conception rate were similar (P > 0.05) between HPP and BH and between HU and LU ewes. Ewes with previous high reproductive performance (HP) as would be expected had higher ovulation rate (P < 0.001) and conception rate (P < 0.01) than LP ewes. Embryo losses was not (P = 0.06) different between HB and HPP ewes. Urea category (HU vs LU) did not (P > 0.05) influence embryo mortality. Foetal loss, neonatal loss, total reproductive loss and mean lamb birth weight was were not affected by diet, nor urea category (P > 0.05). Single ovulations had tended (P = 0.08) to contribute to higher embryo loss compared to multiple ovulations, and, single foetuses suffered higher (P<0.001) losses compared to multiples. While the study did not achieve large differences in plasma urea concentrations between diets, the levels of plasma urea operating were high yet reproductive wastage rates were similar to those recorded in the literature. Together with similar apparent lack of effect on a high plasma urea environment, the data suggest either that previous findings from controlled studies have a more complex aetiology or that pastoral animals can adapt to high tissue ammonia/urea status. The third trial (Chapter 5) was designed to provide information on the supply of amino acids to the abomasum from protein supplementation which have previously been found to overcome dietary scarcity associated with limitation of peri-parturient increase in FEC. Twin-suckling ewes were fitted with rumen and abomasal cannulae and grazed a ryegrass/clover sward (C) or the same sward but with a 500 g/h/d protein supplement (S). The trial was designed as a cross-over with two 14 day adaptation periods followed by two five-day digesta-sampling periods. All ewes were treated with anthelmintic 14 days after lambing. Weekly analysis of blood glucose was carried on whole blood and analysis of amino acids in plasma. The flows of amino acids (AA) and dry matter (DM) at the abomasum were measured during both sampling periods using intra-ruminally infused markers. Live weight and faecal egg count (FEC) were recorded weekly. Diurnal variation in AA flow at the abomasum peaked between 12:00 and 15:00 h and was greatest in S ewes. Flows of AA, including DAPA, were increased by supplementation by 16%, while sulphur amino acids (SAA) were the most enhanced (by 21%) and flows of leucine, lysine, glutamine and aspartate were increased by about 20%. There were significant time effects in rumen and abomasal pH (P < 0.01; in both cases in both periods) reflecting increase in pH after 09.00 h. During Period II, rumen pH in digesta of C ewes was significantly higher (P < 0.001) than that of S ewes (6.7 ± 0.05 vs 6.4 ± 0.05 for C and S ewes, respectively). Plasma AA concentrations (P < 0.01) were lower in S ewes 21 days after parturition, but similar (P > 0.05) to those of C ewes at other times. Forty-three days after lambing (after cross over), the order was reversed as plasma methionine and cysteine concentrations of C ewes became low (P < 0.05). These changes in plasma AA were accompanied by changes in body condition score between day 23 and 70 post-partum whereby C ewes lost more body condition than S ewes. There was evidence for a lower FEC in S ewes, being 46 vs. 670 epg, respectively for S and C groups (P = 0.08) 21 days after anthelmintic treatment. There were higher (P < 0.05) blood glucose levels in C compared to S ewes at day +35 relative to lambing which was reversed and significantly higher (P < 0.01) for S ewes by day +56 from lambing (after treatments were reversed). There was no significant effect of treatment on live weight and lamb performance. There are limited data in amino acid supply on lactating ewes on pasture and the present study contributes additional information on the supply of amino acids at the abomasum. The prediction that flow rates that sulphur amino acids may have been enhanced to the greatest degree could be significant since sulphur amino acids are needed for the synthesis of glutathione for immune response. It can be calculated that supplementation to supply the quantities of S-amino acid at pasture would be needed, since it would not be possible for sheep to increase pasture intake to achieve similar S-amino acid flow. Increase in bypass amino acids in S ewes at certain times in the day probably suggests influence by protein supplementation at certain times of the grazing cycle. Reduced plasma free amino acids at day +21 relative to lambing, may indicate sparing of body protein breakdown by protein supplementation. However, the difference in blood glucose on day 35 and day 56 may indicate re-adjustment of hormonal settings, responsible for nutrient partitioning. The last study (Chapter 6) used ewes during the peri-parturient period on pasture. Eighty pregnant ewes were allocated into four groups balanced for anticipated number of lambs. Group 1 had a high body condition score (BCS) of 4.0 which was maintained throughout pregnancy by pasture allowance (HM; n = 20). Group 2 (n= 40) had medium body condition (BCS 3.0) and were split into two subgroups; one was offered pasture to allow gain of condition (MH; n = 20) and the second allowed to lose condition by offering a low grazing allowance (ML; n = 20). Group 3 were thin ewes (BCS 2.4) and pasture allowance was designed to maintain this condition (LM; n = 20). These feeding regimes were maintained for 3 weeks from week -8 of pregnancy. During week -5 to -4 all ewes were acclimatized to a protein supplement (60 g/d). A glucose tolerance test (GTT) was conducted during week -4 after which half of the ewes in each group were offered a protein supplement at the rate of 500 g/d, creating –S and –NS groups. During wk -2, a second GTT was carried out. Animals were treated with an anthelmintic 3 wks before lambing, and were then challenged with a dose of 10 000 Teladorsagia circumcincta larvae on weeks -2 and -1 relative to lambing. Weekly recording of FEC, live weight and body condition was carried out. Lambs were weighed within 24 h of birth and again at 44 and 65 d of age. Computed tomography body scanning was carried out on ewes at weeks -8, -3 and +8 relative to lambing. There were no differences (P > 0.05) in lamb performance due to body condition or protein supplementation. FEC of all groups was low (≈ 9 peg) and there was no (P > 0.05) significant difference between ewes of different body condition or due to effects of protein supplementation. Ewes bearing/bearing multiple lambs had the highest FEC at day -32 and +12 relative to lambing, which was significant (P < 0.05) on the latter date. There were no significant effects of supplementation on parasite status. There were differences in basal plasma glucose concentration between groups (P < 0.001), being highest in HM/S and least in ML/NS ewes and was generally higher (P <0.001) during GTT 2 than GTT 1. Ewes carrying a single foetus had higher (P <0.001) basal glucose than those carrying multiple lambs (2.2 vs. 1.7 mmol/L, respectively). Other plasma glucose response indexes were similar (P <0.05) between groups. There were differences in insulin responsiveness between groups (P < 0.001), being highest in MH/S and least in ML/S ewes. Insulin responsiveness tended (P = 0.06) to be lower during GTT 1 than GTT 2, but was higher (P < 0.01) in ewes carrying singles than multiples. There was tendency for higher though non-significant, basal insulin concentrations in HM ewes. Insulin trends over time after glucose infusion suggest greater insulin response at GTT 1. Basal insulin was not correlated with CT muscle weight. Despite differences in body muscle mass at the start of the trial and differences induced by nutrition during late pregnancy, positive gains in muscle mass occurred during early pregnancy and muscle mass was similar in all groups by day 56 of lactation. Animals with greatest fat content at parturition (HM) mobilised the greatest amount and those with least fat (LM) deposited fat during lactation. Further experimentation may consider the use of the hyperinsulinemic-euglycemic clamp approach to more precisely estimate whether hormonal re-setting through insulin resistance may be involved in relaxation of immunity during the peri-parturient period.

Copy of author's previously published work inserted. Bibliography: leaves 261-306. The objectives of the project were: i. to determine whether there are competitive interactions between Aporrectodea trapezoides and A. caliginosa and A. rosea.--ii. to investigate compeditive interactions between A. calignosa, Microscolex dubius and A. trapezoides.--iii . to determine the likely impact of A. longa on soil fauna, especially the native earthworm, Gemascolex lateralis, in native ecosystems.

<p>One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline. The results indicate that the number of vascular plants were significantly lower in the abandoned areas than the still managed areas. Results, only from the field layer, showed same results. There was a significant difference between the number of indicators in managed lands than lands that were abandoned for 30-40 and 100 years ago. A comparison from earlier study, from a time when grazing had just ceased at some islands, showed a significant difference in plant species diversity between the years. Just a few decades can impoverish a plant community that might have taken hundreds or even thousands of years to build up. To preserve the biological diversity formed by human impact, one must continue managing the lands.</p> / <p>En av de största orsakerna till den massiva förlusten av växtarter, är fragmenteringen av habitat. I Europa är öppna naturbetesmarker och ängar de habitat som genomgått de största förändringarna i och med jordbrukslandskapets omstruktureringar under 1900-talet. I den här studien inventerades kärlväxter på 5 olika öar i kulturlandskapet Lurö skärgårds naturreservat. Syftet var att ta reda på hur diversiteten bland kärlväxtarter skiljer sig mellan hävdade gräsmarker och f.d. gräsmarker där hävd upphört och hur ett förändrat landskap spelat roll för artantalets utveckling eller tillbakagång. Resultat visade att antalet kärlväxter var signifikant lägre i marker som slutat hävdas, än marker som fortfarande hävdas. Även jämförelser i enbart fältskiktet visade ett signifikant högre artantal hos välhävdade marker än marker där hävd upphört. Det fanns en signifikant skillnad mellan antalet indikatorarter i marker som var under hävd och marker som slutat hävdas för 30-40 år sedan, kontra 100 år sedan. Vid jämförelser med en tidigare studie, som ägt rum precis efter att hävden upphört på ett flertal lokaler visade resultat att det fanns en signifikant skillnad i artantal mellan de båda åren. På några få decennier kan ett helt växtsamhälle som byggts upp under hundratals eller kanske till och med tusentals år utarmas. För att bevara den biologiska mångfald som formas av en störningsregim beroende av människans inverkan, måste hävd fortsätta kontinuerligt.</p>

One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline. The results indicate that the number of vascular plants were significantly lower in the abandoned areas than the still managed areas. Results, only from the field layer, showed same results. There was a significant difference between the number of indicators in managed lands than lands that were abandoned for 30-40 and 100 years ago. A comparison from earlier study, from a time when grazing had just ceased at some islands, showed a significant difference in plant species diversity between the years. Just a few decades can impoverish a plant community that might have taken hundreds or even thousands of years to build up. To preserve the biological diversity formed by human impact, one must continue managing the lands. / En av de största orsakerna till den massiva förlusten av växtarter, är fragmenteringen av habitat. I Europa är öppna naturbetesmarker och ängar de habitat som genomgått de största förändringarna i och med jordbrukslandskapets omstruktureringar under 1900-talet. I den här studien inventerades kärlväxter på 5 olika öar i kulturlandskapet Lurö skärgårds naturreservat. Syftet var att ta reda på hur diversiteten bland kärlväxtarter skiljer sig mellan hävdade gräsmarker och f.d. gräsmarker där hävd upphört och hur ett förändrat landskap spelat roll för artantalets utveckling eller tillbakagång. Resultat visade att antalet kärlväxter var signifikant lägre i marker som slutat hävdas, än marker som fortfarande hävdas. Även jämförelser i enbart fältskiktet visade ett signifikant högre artantal hos välhävdade marker än marker där hävd upphört. Det fanns en signifikant skillnad mellan antalet indikatorarter i marker som var under hävd och marker som slutat hävdas för 30-40 år sedan, kontra 100 år sedan. Vid jämförelser med en tidigare studie, som ägt rum precis efter att hävden upphört på ett flertal lokaler visade resultat att det fanns en signifikant skillnad i artantal mellan de båda åren. På några få decennier kan ett helt växtsamhälle som byggts upp under hundratals eller kanske till och med tusentals år utarmas. För att bevara den biologiska mångfald som formas av en störningsregim beroende av människans inverkan, måste hävd fortsätta kontinuerligt.

Im Rahmen des Pilotprojektes Mulde wurde die Schwermetallbelastung landwirtschaftlich und gärtnerisch genutzter Böden untersucht. Als Ergebnis der Bodenuntersuchungen und der Boden-Pflanze-Beziehungen wurden Belastungskarten der untersuchten Gebiete angefertigt.