As áreas variáveis de afluência (AVAs) são dinâmicas, apresentando expansão das áreas saturadas durante os eventos de chuva, geralmente próximas aos cursos d\'água e, no momento que a chuva cessa, estas áreas saturadas se contraem. O escoamento superficial ocorre nessas áreas devido ao excesso de saturação, provocado pelo aumento do volume d\'água armazenado no perfil de solo e, extravasamento nas áreas com solos rasos, próxima aos rios. Dessa forma, faz-se necessário quantificar o processo de escoamento superficial para a correta delimitação das AVAs. A utilização dos modelos hidrológicos para essa finalidade teve início após legislação estadunidense que define níveis máximos permitidos para poluição difusa. Diversos modelos foram desenvolvidos para quantificar a entrada de poluentes nos corpos hídricos, entretanto não havia maneira precisa de localizar as áreas variáveis de afluência, sendo estas as mais propensas a carrear os contaminantes. Somente através da utilização de modelos hidrológicos distribuídos foi possível considerar o componente espacial, ou seja, a localização exata da ocorrência dos processos hidrológicos, e sua inter-relação com uso de solo e tipo de solo, permitindo testar diferentes cenários avaliando quais áreas convertidas em florestas contribuiriam para maior ganho de serviços ecossistêmicos relacionados à manutenção de recursos hídricos. Portanto, foram modelados 3 cenários: o cenário atual, o cenário AVA e o cenário Código Florestal. O primeiro representa a situação atual do uso do solo, e fornece base para comparação com outros cenários. A probabilidade de saturação para este cenário foi definida com uso do modelo hidrológico GSSHA, permitindo delimitar as áreas variáveis de afluência e criar o cenário AVA, o qual simula a restauração florestal em todas as áreas variáveis de afluência. Por último, foi modelado o cenário Código Florestal, que simula a restauração florestal das áreas de preservação permanentes (APPs), com a função de avaliar quais os impactos para a manutenção dos recursos hídricos caso seja cumprido o Código Florestal (Lei nº. 4.711/65) e sejam restauradas todas as áreas de preservação permanente. Os resultados mostram que a restauração das AVA, com alteração de apenas 4,04% da área total da bacia, aumentaria em 48% a infiltração da água no solo, eliminando a geração de escoamento superficial em áreas agrosilvopastoris e conseqüente carreamento de poluentes provenientes dessas áreas. A restauração das APPs representa uma alteração de 9,36% da área da bacia e promove a recuperação da dinâmica de expansão e contração das nascentes da bacia hidrográfica, que garante redução da vazão e atraso do pico de vazão, evitando respostas hidrológicas hortonianas na bacia hidrográfica. Ambos cenários apresentam benefícios para manutenção dos recursos hídricos. As áreas de preservação permanente apresentam papel significativo na proteção dos recursos hídricos, protegendo mais de 60% das AVAs e sendo de fácil delimitação. A utilização do índice topográfico como variável substituta à modelagem hidrológica apresentou correlação de ~0,33, que permite utilizar o índice para uma análise exploratória, porém insuficiente para delimitar as áreas variáveis de afluência. / The variables source areas (VSA) are dynamic, showing expansion of saturated areas during rain events, usually near to streams and, at the time the rain stops, these saturated areas contract. Runoff occurs in these areas due to saturation excess overland flow, caused by increased of stored volume water in the soil profile, and extravasation in areas with shallow soils, next to streams. Thus, it is necessary to quantify the process of runoff for the correct delineation of VSA. The use of hydrological models for this purpose began after U.S. law which sets maximum permitted levels for diffuse pollution. Several models have been developed to quantify the entry of pollutants in water bodies, however there was no accurate way to pinpoint variables source areas, which are the most likely to carrying contaminants. Only through the use of distributed hydrological models was possible to consider the spatial component, in other words, the exact location of the occurrence of hydrological processes and their interrelationship with land use and soil type, allowing you to test different scenarios by assessing which areas converted to forests contribute to greater gains in ecosystem services related to maintenance of water resources. Therefore, were evaluated three scenarios: the actual scenario, the VSA scenario and the Forest Code scenario. The first one represents the current state of land use and provides a basis for comparison with other scenarios. The probability of saturation for this scenario was defined using the hydrological model GSSHA, allowing to delimit variables source areas and to create the VSA scenario, which simulates forest restoration in all variables source areas. Finally, was modeled the Forestry Code scenario, which simulates forest restoration of permanent preservation areas (PPA), whose function is to assess the impacts for the maintenance of water resources if it complied the Forest Code (Law nº. 4.711/65) and restored all permanent preservation areas. The results show that the restoration of the VSA, with only a 4,04% change of the total area of the watershed, it would increase in 48% water infiltration into the soil, eliminating the generation of surface runoff and consequent carry pollutants from these areas. The restoration of the PPA represents a change of 9,36% of the watershed area and promotes the recovery of dynamic expansion and contraction of the headwaters of the watershed, which ensures reduction in flow rate and delay peak flow, avoiding answers hortonian in the hydrological basin. Both scenarios provide benefits for maintenance of water resources. The permanent preservation areas have significant role in protecting water resources, protecting more than 60% of VSA and being easy delimitation. The use of topographic index as surrogate parameter correlated to the hydrological modeling of ~ 0,33, which allows use the index to an exploratory analysis, but insufficient to delineate the variables source areas.

Adaptive collaborative (co-) management has received increased recognition as a novel approach to environmental governance that combines the dynamic learning features of adaptive management with the linking and network features of collaborative management. This approach is concerned with fostering sustainable livelihoods and ecological sustainability in the face of uncertainty and change. Despite the growing interest in adaptive co-management, little is known about processes useful for catalyzing adaptive co-management arrangements. This paper considers the potential of a government-led initiative designed to build capacity for adaptive collaborative management. We present the results of our study comparing the outcomes of this approach to those forwarded by the adaptive co-management literature, identifying process and context factors that influence the initiative's effectiveness. A multi-case study approach was utilized to assess the degree to which the initiative helped catalyze adaptive co-management of public-lands riparian areas in seven cases in the western U.S. We found that the initiative influenced improvements in knowledge, trust among participants, and shared understanding. In most cases the initiative also helped work towards improvements in the management of specific community-level riparian issues. However, the initiative had a limited influence on the self-organization of new or modified governance arrangements capable of supporting cross-scale networks and ongoing cycles of learning from actions; key features of adaptive co-management. We found that employing adaptive co-management processes did not necessarily result in ongoing adaptive co-management arrangements. The presence of exogenous factors such as existing group capacity and facilitative leadership played an important role in determining whether the riparian initiative resulted in lasting outcomes, regardless of the approach used. We also identified constraints affecting the initiative's ability to facilitate authentic dialogue and develop high-quality agreements. Our results suggest that government-led interventions aimed at catalyzing the transformation of governance arrangements toward adaptive co-management may face significant barriers. Suggestions for future research include further investigation of the barriers and opportunities for government to help catalyze adaptive co-management, and the role of scale in the emergence of ongoing cross-scale networks. / Graduation date: 2012

Made available in DSpace on 2016-12-12T20:12:33Z (GMT). No. of bitstreams: 1 PGEF15MA045.pdf: 2685012 bytes, checksum: 4acd01767b6cb362dbdc068d1ce9cf23 (MD5) Previous issue date: 2015-04-29 / Riparian Forests is importante ecological systems for vital maintenence of the landscape of its rivers. This study aimed to characterize the physicochemical properties of forest soils and verifying the relationship with the structure the floristic composition and diversity of the riparian forest of the Pelotas River along na altitudinal gradiente. There were installed four plots with dimensions of 30 x 30 m, divided into nine sub-plots of 10 x 10 m in each of three áreas of study, so called: one área (28° 30 58 W) 1700 meters; Area 2 (28°19 58 S 0 49°40 27 W) 0- 1200 meters; Area 3 (28° 28 39,65 S - 50° 04 03,73 W) 850 meters. All individuals presente in plots with 5 &#706;_ cm DAP they were identified. Species were classified in: ecological groups, dispersion strategy. For the analysis physicalchemical properties of the soil, we used principal componente analysis (PCA). The existence of floristic-structural diferences between the three áreas studied was verified by a Multivariate Analysis of Variance permutation (PERMANOVA). It was the influence of the physicochemical properties of soil on vegetation by linear adjustments of environmental variables by ordering produced by analysis of Multidimensional Nonmetric Scalling (NMDS), and those siginificant variables (p&#706;0.001) pltted as vectors. Trough the phytosociological descriptors measured the forest structure. The diversity was assessed using the diversity index of Shannon-Wiener (H ), Pielou evennes (J ). there was the phytogeographic features: endemic species or non-endemic to the Atlantic Rainforest. 77 species, gathered in 33 families and 52 genera were identified. Myrtaceae (16), Solanaceae (five) and Lauraceae (four) were the richest families. As regardsthe ecological group: Pionners 20%; Secondary 62%; Climax 18%. As the dispersion syndrome: Zoochoric 82%; Anemochoric 13%; Autochorous 5%; showed a high heterogeneity of soil conditions: higher altitude had more acidic and less fertile soils; places with lower altitudes showed less acidic and more fertile soils. The NMDS showed that the tree componente showed variation related to changes in the soil environment and the altitude separating the floristic composition into two distinct groups. The Shannon-Wiener diversity and evenness were: área (H / j ): 1 (1.28 to 0.42); 2 (2.40 to 0.68); 3 (3.28 to 0.83). The diameter distribution showed fotrm of inverted J . Among the endemic species of the Atlantic Forest, the highlights: Crinodendron brasiliensis Reitz & LB Sm beig located strictly in santa catarina Area 1 and Luchea divaricata Mart. & Zucc. Being located only in Area 3, but with wide distribution in he Atlantic Forest. We concluded a high edaphic heterogeneity along the altitudinal gradiente, directly influencing the floristic composition of riparian forest, causing a high floristic substitution between study áreas, significantly increasing the fiversity and the tree structure of Riparian Forest of Rio Pelotas of local higher altitude to the lower altitude / As Florestas Ciliares constituem sistemas ecológicos importantes para a manutenção dos rios. Objetivou-se caracterizar a composição florística, estrutura e a diversidade da Floresta Ciliar do Rio Pelotas ao longo de um gradiente altitudinal e relacioná-las com as propriedades físicas e químicas de solos florestais. Foram instaladas quatro parcelas com dimensões de 30 x 30 m, subdivididas em nove subparcelas de 10 x 10 m, em cada uma das três áreas de estudo, assim denominadas: Área 1 (280 8&#8223;18&#8223;&#8223; S 490 30&#8223;58&#8223;&#8223; O) - 1700 metros; Área 2 (28019&#8223; 58&#8223;&#8223; S 49040&#8223; 27&#8223;&#8223; O) - 1200 metros; Área 3 (280 28&#8223;39,65 S 500 04&#8223;03,73 O) - 850 metros. Todos os indivíduos, presentes nas parcelas, com &#8805; cinco cm de DAP foram levantados. Classificaram-se as espécies em: grupos ecológicos e estratégia de dispersão. Para a análise das propriedades físicas e químicas dos solos, utilizou-se Análise de Componentes Principais (PCA). A existência de diferenças florísticas-estruturais entre as três áreas estudadas foi verificada por meio de uma Análise de Variância Multivariada Permutacional (PERMANOVA). Verificou-se a influência das propriedades físicas e químicas dos solos sobre a vegetação por meio de ajustes lineares das variáveis ambientais pela ordenação produzida pela análise de Escalonamento Multidimensional Não-Métrico (NMDS), sendo aquelas variáveis significativas (p < 0,001) plotadas na forma de vetores. Através dos descritores fitossociológicos mediu-se a estrutura da floresta. A diversidade foi avaliada utilizando-se o índice diversidade de Shannon-Wiener (H&#8223;), equabilidade de Pielou (J&#8223;). Observou-se às características fitogeográficas: Espécies endêmicas ou não endêmicas da Mata Atântica. Foram identificadas 77 espécies, reunidas em 33 famílias e 52 gêneros. Myrtaceae (16), Solanaceae (cinco) e Lauraceae (quatro) foram às famílias de maior riqueza. Quanto ao grupo ecológico: Pioneiras 20%; Secundarias 62%; Climácicas 18%. Quanto à Síndrome de dispersão: Zoocorica 82%; Anemocorica 13%; Autocorica 5%;. A PCA indicou uma elevada heterogeneidade das condições edáficas: local com maior altitude apresentou solos mais ácidos e menos férteis; os locais com menores altitudes apresentaram solos menos ácidos e mais férteis. A NMDS mostrou que o componente arbóreo apresentou variações associadas à variação do ambiente edáfico e a altitude separando a composição florística em dois grupos distintos. A diversidade Shannon-Wiener e equabilidade Pielou foram: Área (H&#8223; / J&#8223;): 1 (1,28 - 0,42); 2 (2,40 - 0,68); 3 (3,28 - 0,83). A distribuição diamétrica mostrou forma de J invertido. Dentre as espécies endêmicas da Mata Atlântica, se destacaram: Crinodendron brasiliense Reitz & LB Sm localizando-se restritamente em Santa Catarina Área 1 e Luehea divaricata Mart. & Zucc. localizando-se apenas na Área 3, porém com ampla distribuição na Mata Atlântica. Concluí-se uma elevada heterogeneidade edáfica ao longo do gradiente altitudinal, influenciando diretamente na composição florística de floresta ciliar, ocorrendo uma elevada substituição florística entre as áreas de estudo, aumentando significativamente a diversidade e a estrutura arbórea de Floresta Ciliar do Rio Pelotas dos locais de maior altitude para os de menor altitude

As áreas variáveis de afluência (AVAs) são dinâmicas, apresentando expansão das áreas saturadas durante os eventos de chuva, geralmente próximas aos cursos d\'água e, no momento que a chuva cessa, estas áreas saturadas se contraem. O escoamento superficial ocorre nessas áreas devido ao excesso de saturação, provocado pelo aumento do volume d\'água armazenado no perfil de solo e, extravasamento nas áreas com solos rasos, próxima aos rios. Dessa forma, faz-se necessário quantificar o processo de escoamento superficial para a correta delimitação das AVAs. A utilização dos modelos hidrológicos para essa finalidade teve início após legislação estadunidense que define níveis máximos permitidos para poluição difusa. Diversos modelos foram desenvolvidos para quantificar a entrada de poluentes nos corpos hídricos, entretanto não havia maneira precisa de localizar as áreas variáveis de afluência, sendo estas as mais propensas a carrear os contaminantes. Somente através da utilização de modelos hidrológicos distribuídos foi possível considerar o componente espacial, ou seja, a localização exata da ocorrência dos processos hidrológicos, e sua inter-relação com uso de solo e tipo de solo, permitindo testar diferentes cenários avaliando quais áreas convertidas em florestas contribuiriam para maior ganho de serviços ecossistêmicos relacionados à manutenção de recursos hídricos. Portanto, foram modelados 3 cenários: o cenário atual, o cenário AVA e o cenário Código Florestal. O primeiro representa a situação atual do uso do solo, e fornece base para comparação com outros cenários. A probabilidade de saturação para este cenário foi definida com uso do modelo hidrológico GSSHA, permitindo delimitar as áreas variáveis de afluência e criar o cenário AVA, o qual simula a restauração florestal em todas as áreas variáveis de afluência. Por último, foi modelado o cenário Código Florestal, que simula a restauração florestal das áreas de preservação permanentes (APPs), com a função de avaliar quais os impactos para a manutenção dos recursos hídricos caso seja cumprido o Código Florestal (Lei nº. 4.711/65) e sejam restauradas todas as áreas de preservação permanente. Os resultados mostram que a restauração das AVA, com alteração de apenas 4,04% da área total da bacia, aumentaria em 48% a infiltração da água no solo, eliminando a geração de escoamento superficial em áreas agrosilvopastoris e conseqüente carreamento de poluentes provenientes dessas áreas. A restauração das APPs representa uma alteração de 9,36% da área da bacia e promove a recuperação da dinâmica de expansão e contração das nascentes da bacia hidrográfica, que garante redução da vazão e atraso do pico de vazão, evitando respostas hidrológicas hortonianas na bacia hidrográfica. Ambos cenários apresentam benefícios para manutenção dos recursos hídricos. As áreas de preservação permanente apresentam papel significativo na proteção dos recursos hídricos, protegendo mais de 60% das AVAs e sendo de fácil delimitação. A utilização do índice topográfico como variável substituta à modelagem hidrológica apresentou correlação de ~0,33, que permite utilizar o índice para uma análise exploratória, porém insuficiente para delimitar as áreas variáveis de afluência. / The variables source areas (VSA) are dynamic, showing expansion of saturated areas during rain events, usually near to streams and, at the time the rain stops, these saturated areas contract. Runoff occurs in these areas due to saturation excess overland flow, caused by increased of stored volume water in the soil profile, and extravasation in areas with shallow soils, next to streams. Thus, it is necessary to quantify the process of runoff for the correct delineation of VSA. The use of hydrological models for this purpose began after U.S. law which sets maximum permitted levels for diffuse pollution. Several models have been developed to quantify the entry of pollutants in water bodies, however there was no accurate way to pinpoint variables source areas, which are the most likely to carrying contaminants. Only through the use of distributed hydrological models was possible to consider the spatial component, in other words, the exact location of the occurrence of hydrological processes and their interrelationship with land use and soil type, allowing you to test different scenarios by assessing which areas converted to forests contribute to greater gains in ecosystem services related to maintenance of water resources. Therefore, were evaluated three scenarios: the actual scenario, the VSA scenario and the Forest Code scenario. The first one represents the current state of land use and provides a basis for comparison with other scenarios. The probability of saturation for this scenario was defined using the hydrological model GSSHA, allowing to delimit variables source areas and to create the VSA scenario, which simulates forest restoration in all variables source areas. Finally, was modeled the Forestry Code scenario, which simulates forest restoration of permanent preservation areas (PPA), whose function is to assess the impacts for the maintenance of water resources if it complied the Forest Code (Law nº. 4.711/65) and restored all permanent preservation areas. The results show that the restoration of the VSA, with only a 4,04% change of the total area of the watershed, it would increase in 48% water infiltration into the soil, eliminating the generation of surface runoff and consequent carry pollutants from these areas. The restoration of the PPA represents a change of 9,36% of the watershed area and promotes the recovery of dynamic expansion and contraction of the headwaters of the watershed, which ensures reduction in flow rate and delay peak flow, avoiding answers hortonian in the hydrological basin. Both scenarios provide benefits for maintenance of water resources. The permanent preservation areas have significant role in protecting water resources, protecting more than 60% of VSA and being easy delimitation. The use of topographic index as surrogate parameter correlated to the hydrological modeling of ~ 0,33, which allows use the index to an exploratory analysis, but insufficient to delineate the variables source areas.

Indiana University-Purdue University Indianapolis (IUPUI) / This study investigates the hydrological functioning of a riparian zone in central Indiana in a glaciated valley with concave topography (16% slope gradient) and ground water seeps on the valley walls. Unlike sites found in most riparian zone studies with lateral ground water inputs (Clement et al., 2003; Jordan et al., 1993; Blicher-Mathiesen and Hoffman, 1999; Hoffman et al., 2000), the site in this study is connected to thin, permeable upland sediments (≈2 m). The objectives of this research include: 1) understanding the influence of the hydrogeomorphic (HGM) setting on riparian hydrology (including determining the sources of water to the site), 2) determining how the HGM setting influences riparian zone water quality functioning, and 3) comparing the results from this site with conceptual models of riparian zone hydrologic functioning. Water chemistry and hydrometric data were collected over a 16-month period. Three factors influence riparian zone hydrological functioning at the site: 1) the nature of water contributions from upland sources, 2) riparian zone soil texture, and 3) the location of a preWisconsinan till unit. When the uplands are contributing water to the riparian zone a shallow water table is found near the hillslope and ground water flows from the hillslope to the stream. Conversely, when upland contributions cease a large water table drop occurs and ground water flows in a downvalley direction. Fine textured soils near the hillslope result in shallow water tables and small ground water fluxes. Hydrometric data, water chemistry, and statistical analyses suggest water from an intertill layer adjacent to the site is the primary source of water to the site. NO3- concentrations decreased in ground water flow in the riparian zone suggesting the site is removing nutrients. A preWisconsinan glacial till deposit at shallow depths in the riparian zone limits ground water flow to horizontal flow paths. Overall, the hydrologic functioning of the site agrees well with riparian zone conceptual models (Vidon and Hill, 2004a; Vidon and Hill, 2004b; Devito et al., 1996; Hill, 2000; Baker et al., 2001; Burt et al., 2002). The results of this study are important additions towards conceptualizing riparian zone hydrologic functioning.

Forested lands of western Oregon provide aquatic habitat for many fish and riparian dependent species, including a wide variety of salmon species. Current policies set riparian protections using fixed buffers on streams for federal and private lands based on stream type or size. These buffers can create a series of disjointed riparian protections, as federal lands require buffers that are much larger than private lands. In addition, the fixed buffer approach is neither flexible nor tailored to aquatic ecosystem values. This thesis presents a framework for comprehensively assessing stream networks using site specific watershed features and then suggests riparian conservation strategies that key stream and riparian protection to aquatic ecosystem values. Seven study watersheds were used in this analysis, totaling over 2.5 million acres of forested lands in western Oregon. Employing a set of geospatial tools, called NetMap, streams in each watershed were classified into higher and lower priorities using criteria of intrinsic potential, erosion/debris flow susceptibility, and thermal loading potential. Results demonstrated the inherent variability within and among watersheds based on the geomorphic and ecological processes determined important for selected salmon species. Within each watershed, both federal and non-federal lands had many miles of higher priority fish-bearing and non-fish bearing streams, suggesting the need for comprehensive, holistic watershed conservation strategies. Based on the partitioning of streams into higher and lower priorities, an alternative riparian conservation strategy was then modeled for federal lands that allocate protection on the basis of the ecological context of a stream segment’s potential and particular location while still meeting federal aquatic conservation goals and objectives. Possible increases to the land base for long-term timber production were then identified if this strategy were applied to federal Matrix lands. Results demonstrated that 8-30 percent of the current riparian buffers could be reallocated to the land base for long-term timber production. An additional 26-45 percent of current buffers could be managed simultaneously for both timber production and aquatic ecosystem goals. Results also provided a framework for targeting of conservation and restoration efforts towards higher priority streams within each watershed. As many of the most ecologically important streams were located on non-federal lands, riparian conservation policies focused on streams classified as higher priority on those lands may be needed to protect aquatic species and their environments. / Graduation date: 2013

Thesis (MScConsEcol(Conservation Ecology and Entomology)--University of Stellenbosch, 2007. / Riparian areas are highly complex systems with varying levels of disturbance that are highly susceptible to invasion by alien plants. Once invaded, riparian areas play a major role in the dispersal and spread of invasive alien plants (IAPs) through the river system and, in some cases, to neighbouring landscapes. Riparian areas have therefore been prioritized by many alien clearing initiatives in South Africa. Current practice for the restoration of cleared areas is minimal and relies mainly on the un-aided recovery of native species from residual individuals and soil stored seed banks. Little research, however, has been done on the effectiveness of this approach or the extent to which riparian seed banks contribute towards community restoration. This study is part of a national research initiative (Targets for Ecosystem Repair in Riparian Ecosystems in Fynbos, Grassland and Savanna Biomes) funded by Department of Water Affairs and Forestry, in collaboration with Working for Water, The Centre for Invasion Biology and the Universities of Cape Town, Stellenbosch, Rhodes and Witwatersrand. The initiative undertook to investigate different restoration techniques on various invaded sites for their cost-effectiveness, efficiency, practicality and conservation integrity. This study has three aims. The first is to determine the composition of seed banks in un-invaded riparian areas within the fynbos biome to be used as a benchmark for future research, restoration grading and other management requirements. The second aim is to determine the composition of seed banks in heavily invaded riparian areas, and thus to assess the impact of invasion on the integrity of the seed banks. The third aim is to evaluate the restoration potential of riparian seed banks following the clearing of invasive alien plants (IAPs). Study sites were selected within four river systems in the south-western part of the Western Cape Province in South Africa: the Berg, Eerste, Molenaars and Wit Rivers. Plots were selected in both invaded (>75% IAP canopy cover; considered “closed” alien stands) and un-invaded (also termed reference, with <25% IAP canopy cover) sections of the river. Replicate plots were established along varying gradients of elevation (mountain stream and foothill) and moisture regimes (dry, wet and transitional bank zones). Soil samples were collected together with above-ground vegetation surveys and comparisons were made. Results from this study confirm those of previous studies that seed banks offer little reference to current aboveground vegetation, but rather offer insight into past vegetation history as well as future vegetation assemblages. Worldwide, many of the species that characteristically form seed banks are early successional species. A community study was done for the seed bank based on the species that germinated and were identifiable at termination of the project (6 months after initiation). Three clusters of species could be identified. One group comprised 32 generalist species that occurred in both reference and invaded sections of the rivers. A second group comprised 39 species associated with invaded sites, and a third group of 40 species that was associated with reference sites. A few sub-community groups were found within both the “reference” and “invaded” community groups which were assumed to be habitat specific. Most species were “pioneer” or relatively-short lived, early-successional species which play a vital role in the initial post-disturbance vegetation cover, and facilitate establishment of later successional species. Seed banks are notoriously variable over space and time, and floristic representation is often biased as a result of differences among species in seed production, dispersal and longevity in the soil. The general consensus is that seeds have an irregular, clustered spatial distribution that is dictated by both biological and environmental factors. Within river systems, the irregular clustering can be exceptionally skewed with the influence of pockets of high sediment deposition along the bank. Environmental factors that were found to significantly skew germination results were the presence of fire, as well as the extent and intensity of invasion (duration and cover). The high level of diversity and abundance in reference Berg River mountain stream seed banks was perceived to be a direct result of a moderate fire frequency (between 8-15 years) and the relatively natural state of the vegetation (i.e. very little invasion). Also, diversity and richness of indigenous species from the Wit and Molenaars Rivers were substantially higher in the invaded samples than the reference samples, probably because both river systems have a long history of invasion and other anthropogenic disturbances which would have an effect on the samples from “reference” sections (i.e. even a 25% presence of IAPs seems adequate enough to alter the composition of the seed bank). Correspondence analyses showed that species had clear affinities towards different levels of “key” riparian environmental variables (fire, invasion and anthropogenic disturbance). Most species were associated with moderate levels of fire frequency, invasion history, and anthropogenic disturbance. Comparisons of seed bank species assemblages between the lateral and longitudinal variables of the rivers offered insights into the habitat requirements of certain fynbos and riparian species. Most significant were the results from bank zone comparisons which showed distinct species groupings along the different moisture bands. As could be expected, riparian species were best represented within the wet bank zones and fynbos species within the dry bank zone, while species characteristic of both zones occurred in the transitional zone, making this seed bank zone the richest in species. Mountain stream sections were richer and more diverse than foothill sections over both invaded and reference samples. This is hypothesised to be linked to lower levels of anthropogenic disturbance experienced in the mountain stream sections. The impact of invasion on the riparian seed bank was most clearly shown through the correspondence analyses for the 20 most frequently occurring species. The seed bank assembly patterns were clearly defined by the state of the river (reference or invaded). Interestingly, this pattern was evident at all three spatial scales; landscape (rivers), reach (mountain stream and foothill sections) and habitat (dry, wet and transitional zones). The reference seed bank assemblage was more tightly grouped, implying that the species were more closely associated with each other and less variable than those of the invaded seed bank assemblages. The species groupings within the invaded seed banks were influenced by variables such as reach and zone, whereas the reference seed bank assemblages seem relatively unaffected by these variables. This implies that the presence of invasive alien plants creates additional variation within the seed bank which alters the natural groupings. At a broad scale, the invaded seed banks were less species rich. This means that not only will the resulting seedling community be harder to predict, but it will also have fewer species. However although generally lower in species richness, the seed banks from almost all invaded rivers interestingly showed a higher diversity of indigenous species than their reference counterparts. This is very promising in terms of rehabilitation of post-cleared riparian sites, but more information is needed to understand the seed bank composition and determine how sustainable the seed banks are for rehabilitation in the long-term. All invaded sections had fewer herbaceous perennial species but more herbaceous annual species. Graminoids made up 50% or more of the seed bank regardless of state (reference or invaded), while woody species (shrubs/shrublets) were generally more prevalent in the reference samples. These results imply that following the removal of invasive alien plants, the vegetation to regenerate from the seed bank is likely to comprise of short-lived, herbaceous species that are not necessarily an accurate reflection of the indigenous riparian community. It is however important to note that this study investigated only the species that were able to germinate over the study period (6 month germination period). Many riparian species may not have been represented because they are either late germinators or may not be present in the soil seed bank at all. In order to gain a holistic understanding of riparian community recruitment, it is recommended that seed bank studies such as this one be included in a more broad scale, long term investigation which takes into account various reproductive strategies used by riparian species. Research of this nature is in its infancy worldwide and there are many challenges involved in measuring diversity and change in these systems. However, within the scope of this study, I suggest that these results shed light on previously unanswered and important questions regarding the ecology of seed banks in the riparian ecosystems of the Western Cape.

<p>Имајући&nbsp; у&nbsp; виду&nbsp; значај&nbsp; површинских&nbsp; вода&nbsp; у продору&nbsp; и&nbsp; ширењу&nbsp; страних&nbsp; инвазивних врста,&nbsp; циљеви&nbsp; овог&nbsp; рада&nbsp; били&nbsp; су&nbsp; да&nbsp; се представи&nbsp; актуелно&nbsp; стање&nbsp; присуства&nbsp; и дистрибуције&nbsp; акватичних&nbsp; инвазивних биљних&nbsp; врста&nbsp; у&nbsp; површинским&nbsp; копненим водама,&nbsp; анализира&nbsp; степен&nbsp; инвазије рипаријалних&nbsp; зона&nbsp; на&nbsp; подручју&nbsp; Србије, одреди&nbsp; везаност&nbsp; анализираних&nbsp; инвазивних<br />врста&nbsp; за&nbsp; поједине&nbsp; типове&nbsp; станишта&nbsp; у рипаријалу река и канала и анализира утицај различитих&nbsp; станишних&nbsp; и&nbsp; антропогених фактора&nbsp; на&nbsp; присуство&nbsp; и&nbsp; абунданцу&nbsp; 26 одабраних&nbsp; инвазивних&nbsp; таксона.&nbsp; Теренска истраживања&nbsp; вршена&nbsp; су&nbsp; у&nbsp; периоду&nbsp; од&nbsp; 2013. до&nbsp; 2016.&nbsp; године.&nbsp; За&nbsp; потребе&nbsp; овог&nbsp; рада анализирано је 250 локалитета, од чега 217 у рипаријалу&nbsp; 39&nbsp; река&nbsp; и&nbsp; 33&nbsp; у&nbsp; рипаријалу&nbsp; шест<br />деоница&nbsp; канала&nbsp; хидросистема&nbsp; Дунав-Тиса-Дунав.&nbsp; Уз&nbsp; податке&nbsp; о&nbsp; бројности&nbsp; и<br />покровности&nbsp; заступљених&nbsp; биљних&nbsp; врста, сакупљани&nbsp; су&nbsp; и&nbsp; подаци&nbsp; о&nbsp; типу&nbsp; станишта&nbsp; (у складу&nbsp; са&nbsp; EUNIS&nbsp; класификацијом), релевантним&nbsp; физичким&nbsp; и<br />хидроморфолошким&nbsp; карактеристикама истраживаних&nbsp; водотокова&nbsp; и&nbsp; доминантним антропогеним&nbsp; утицајима&nbsp; на&nbsp; истраживаном локалитету&nbsp; (у&nbsp; складу&nbsp; са&nbsp; стандардним протоколом&nbsp; RHS&nbsp; методе).&nbsp; Статистичка обрада&nbsp; података&nbsp; вршена&nbsp; је&nbsp; у&nbsp; софтверу CANOCO&nbsp; 5.0,&nbsp; применом&nbsp; анализе&nbsp; главних компоненти&nbsp; (РСА),&nbsp; канонијскe коресподентнe&nbsp; анализе&nbsp; (CCA)&nbsp; и&nbsp; анализе редундантности&nbsp; (RDA).&nbsp; На&nbsp; територији Србије&nbsp; забележено&nbsp; је&nbsp; присуство&nbsp; осам акватичних&nbsp; инвазивних&nbsp; биљних&nbsp; врстаПрема&nbsp; броју&nbsp; налаза&nbsp; истичу&nbsp; се&nbsp; врсте Vallisneria spiralis, Azolla filiculoides и Elodea&nbsp; nuttallii.&nbsp; Примарно су заступљене у текућим,<br />у односу на стајаће воде, при чему се мрежа&nbsp; канала&nbsp; ХС&nbsp; ДТД&nbsp; и&nbsp; речни&nbsp; токови&nbsp; који&nbsp; припадају&nbsp; сливу&nbsp; Дунава&nbsp; могу&nbsp; сматрати&nbsp; основним&nbsp; акватичним&nbsp; коридорима&nbsp; њиховог&nbsp; ширења.&nbsp; Од&nbsp; 26&nbsp; таксона&nbsp; инвазивних&nbsp; биљака&nbsp; чије&nbsp; је&nbsp; присуство&nbsp; праћено&nbsp; и&nbsp; анализирано&nbsp; у&nbsp; рипаријалним&nbsp; подручјима,&nbsp; таксони&nbsp; са<br />највећим&nbsp; бројем&nbsp; налаза&nbsp; су&nbsp;<em> Xanthium&nbsp; strumarium</em>&nbsp; subsp.&nbsp; <em>italicum,&nbsp; Amorpha</em> <em>fruticosa, Erigeron&nbsp; canadensis,&nbsp; Robinia&nbsp; pseudoacacia&nbsp; и&nbsp; Echinochloa&nbsp; crus-galli.</em>&nbsp; Речни&nbsp; сливови Дунава,&nbsp; Јужне&nbsp; Мораве,&nbsp; Западне&nbsp; Мораве&nbsp; и&nbsp; Тимока&nbsp; истичу&nbsp; се&nbsp; по&nbsp; заступљености&nbsp; истраживаних таксона. На основу података о дистрибуцији,&nbsp; бројности&nbsp; и&nbsp; покровности&nbsp; анализираних&nbsp; таксона&nbsp; сливови&nbsp; Дунава, Колубаре и Западне Мораве издвојили су се&nbsp; као&nbsp; коридори&nbsp; ширења&nbsp; највећег&nbsp; броја<br />истраживаних&nbsp; таксона.&nbsp; Четири&nbsp; типа&nbsp; станишта&nbsp; издвојила&nbsp; су&nbsp; се&nbsp; према<br />заступљености&nbsp; инвазивних&nbsp; биљних&nbsp; врста.&nbsp; Таксони који су забележени у највећем броју&nbsp; типова&nbsp; станишта&nbsp; су:&nbsp; <em>Amorpha&nbsp; fruticosa, Erigeron&nbsp; canadensis,&nbsp;</em> <em>Robinia&nbsp; pseudoacacia, Echinochloa crus-galli&nbsp;</em> и&nbsp; <em>Xanthium strumarium subsp</em>.&nbsp; <em>italicum.</em>&nbsp; Као&nbsp; резултат&nbsp; нумеричких&nbsp; анализа&nbsp; издвојени&nbsp; су&nbsp; физички&nbsp; и<br />хидроморфолошки параметри истраживаних&nbsp; водотокова&nbsp; и&nbsp; доминантни&nbsp; антропогени&nbsp; утицаји који на истраживаном локалитетима утичу&nbsp; на&nbsp; присуство&nbsp; и&nbsp; абунданцу&nbsp; анализираних&nbsp; таксона.&nbsp; У&nbsp; условима&nbsp; глобалних&nbsp; климатских&nbsp; промена&nbsp; може&nbsp; се&nbsp; очекивати да ће се&nbsp; у наредном периоду под снажним&nbsp; притиском&nbsp; ширења&nbsp; и&nbsp; доминације&nbsp; инвазивних врста наћи сливови Саве, Велике Мораве&nbsp; и&nbsp; Јужне&nbsp; Мораве.&nbsp; У&nbsp; рипаријалним областима на југозападу наше земље (долине Лима,&nbsp; Ибра&nbsp; и&nbsp; њихових&nbsp; притока)&nbsp; као&nbsp; и&nbsp; рипаријалним&nbsp; зонама&nbsp; планинских&nbsp; и високопланинских&nbsp; области&nbsp; такође&nbsp; је очекивано&nbsp; да&nbsp; ће&nbsp; доћи&nbsp; до&nbsp; повећања&nbsp; броја присутних&nbsp; инвазивних&nbsp; врста&nbsp; и&nbsp; њиховог даљег ширења.</p> / <p>Imajući&nbsp; u&nbsp; vidu&nbsp; značaj&nbsp; površinskih&nbsp; voda&nbsp; u prodoru&nbsp; i&nbsp; širenju&nbsp; stranih&nbsp; invazivnih vrsta,&nbsp; ciljevi&nbsp; ovog&nbsp; rada&nbsp; bili&nbsp; su&nbsp; da&nbsp; se predstavi&nbsp; aktuelno&nbsp; stanje&nbsp; prisustva&nbsp; i distribucije&nbsp; akvatičnih&nbsp; invazivnih biljnih&nbsp; vrsta&nbsp; u&nbsp; površinskim&nbsp; kopnenim vodama,&nbsp; analizira&nbsp; stepen&nbsp; invazije riparijalnih&nbsp; zona&nbsp; na&nbsp; području&nbsp; Srbije, odredi&nbsp; vezanost&nbsp; analiziranih&nbsp; invazivnih<br />vrsta&nbsp; za&nbsp; pojedine&nbsp; tipove&nbsp; staništa&nbsp; u riparijalu reka i kanala i analizira uticaj različitih&nbsp; stanišnih&nbsp; i&nbsp; antropogenih faktora&nbsp; na&nbsp; prisustvo&nbsp; i&nbsp; abundancu&nbsp; 26 odabranih&nbsp; invazivnih&nbsp; taksona.&nbsp; Terenska istraživanja&nbsp; vršena&nbsp; su&nbsp; u&nbsp; periodu&nbsp; od&nbsp; 2013. do&nbsp; 2016.&nbsp; godine.&nbsp; Za&nbsp; potrebe&nbsp; ovog&nbsp; rada analizirano je 250 lokaliteta, od čega 217 u riparijalu&nbsp; 39&nbsp; reka&nbsp; i&nbsp; 33&nbsp; u&nbsp; riparijalu&nbsp; šest<br />deonica&nbsp; kanala&nbsp; hidrosistema&nbsp; Dunav-Tisa-Dunav.&nbsp; Uz&nbsp; podatke&nbsp; o&nbsp; brojnosti&nbsp; i<br />pokrovnosti&nbsp; zastupljenih&nbsp; biljnih&nbsp; vrsta, sakupljani&nbsp; su&nbsp; i&nbsp; podaci&nbsp; o&nbsp; tipu&nbsp; staništa&nbsp; (u skladu&nbsp; sa&nbsp; EUNIS&nbsp; klasifikacijom), relevantnim&nbsp; fizičkim&nbsp; i<br />hidromorfološkim&nbsp; karakteristikama istraživanih&nbsp; vodotokova&nbsp; i&nbsp; dominantnim antropogenim&nbsp; uticajima&nbsp; na&nbsp; istraživanom lokalitetu&nbsp; (u&nbsp; skladu&nbsp; sa&nbsp; standardnim protokolom&nbsp; RHS&nbsp; metode).&nbsp; Statistička obrada&nbsp; podataka&nbsp; vršena&nbsp; je&nbsp; u&nbsp; softveru CANOCO&nbsp; 5.0,&nbsp; primenom&nbsp; analize&nbsp; glavnih komponenti&nbsp; (RSA),&nbsp; kanonijske korespodentne&nbsp; analize&nbsp; (CCA)&nbsp; i&nbsp; analize redundantnosti&nbsp; (RDA).&nbsp; Na&nbsp; teritoriji Srbije&nbsp; zabeleženo&nbsp; je&nbsp; prisustvo&nbsp; osam akvatičnih&nbsp; invazivnih&nbsp; biljnih&nbsp; vrstaPrema&nbsp; broju&nbsp; nalaza&nbsp; ističu&nbsp; se&nbsp; vrste Vallisneria spiralis, Azolla filiculoides i Elodea&nbsp; nuttallii.&nbsp; Primarno su zastupljene u tekućim,<br />u odnosu na stajaće vode, pri čemu se mreža&nbsp; kanala&nbsp; HS&nbsp; DTD&nbsp; i&nbsp; rečni&nbsp; tokovi&nbsp; koji&nbsp; pripadaju&nbsp; slivu&nbsp; Dunava&nbsp; mogu&nbsp; smatrati&nbsp; osnovnim&nbsp; akvatičnim&nbsp; koridorima&nbsp; njihovog&nbsp; širenja.&nbsp; Od&nbsp; 26&nbsp; taksona&nbsp; invazivnih&nbsp; biljaka&nbsp; čije&nbsp; je&nbsp; prisustvo&nbsp; praćeno&nbsp; i&nbsp; analizirano&nbsp; u&nbsp; riparijalnim&nbsp; područjima,&nbsp; taksoni&nbsp; sa<br />najvećim&nbsp; brojem&nbsp; nalaza&nbsp; su&nbsp;<em> Xanthium&nbsp; strumarium</em>&nbsp; subsp.&nbsp; <em>italicum,&nbsp; Amorpha</em> <em>fruticosa, Erigeron&nbsp; canadensis,&nbsp; Robinia&nbsp; pseudoacacia&nbsp; i&nbsp; Echinochloa&nbsp; crus-galli.</em>&nbsp; Rečni&nbsp; slivovi Dunava,&nbsp; Južne&nbsp; Morave,&nbsp; Zapadne&nbsp; Morave&nbsp; i&nbsp; Timoka&nbsp; ističu&nbsp; se&nbsp; po&nbsp; zastupljenosti&nbsp; istraživanih taksona. Na osnovu podataka o distribuciji,&nbsp; brojnosti&nbsp; i&nbsp; pokrovnosti&nbsp; analiziranih&nbsp; taksona&nbsp; slivovi&nbsp; Dunava, Kolubare i Zapadne Morave izdvojili su se&nbsp; kao&nbsp; koridori&nbsp; širenja&nbsp; najvećeg&nbsp; broja<br />istraživanih&nbsp; taksona.&nbsp; Četiri&nbsp; tipa&nbsp; staništa&nbsp; izdvojila&nbsp; su&nbsp; se&nbsp; prema<br />zastupljenosti&nbsp; invazivnih&nbsp; biljnih&nbsp; vrsta.&nbsp; Taksoni koji su zabeleženi u najvećem broju&nbsp; tipova&nbsp; staništa&nbsp; su:&nbsp; <em>Amorpha&nbsp; fruticosa, Erigeron&nbsp; canadensis,&nbsp;</em> <em>Robinia&nbsp; pseudoacacia, Echinochloa crus-galli&nbsp;</em> i&nbsp; <em>Xanthium strumarium subsp</em>.&nbsp; <em>italicum.</em>&nbsp; Kao&nbsp; rezultat&nbsp; numeričkih&nbsp; analiza&nbsp; izdvojeni&nbsp; su&nbsp; fizički&nbsp; i<br />hidromorfološki parametri istraživanih&nbsp; vodotokova&nbsp; i&nbsp; dominantni&nbsp; antropogeni&nbsp; uticaji koji na istraživanom lokalitetima utiču&nbsp; na&nbsp; prisustvo&nbsp; i&nbsp; abundancu&nbsp; analiziranih&nbsp; taksona.&nbsp; U&nbsp; uslovima&nbsp; globalnih&nbsp; klimatskih&nbsp; promena&nbsp; može&nbsp; se&nbsp; očekivati da će se&nbsp; u narednom periodu pod snažnim&nbsp; pritiskom&nbsp; širenja&nbsp; i&nbsp; dominacije&nbsp; invazivnih vrsta naći slivovi Save, Velike Morave&nbsp; i&nbsp; Južne&nbsp; Morave.&nbsp; U&nbsp; riparijalnim oblastima na jugozapadu naše zemlje (doline Lima,&nbsp; Ibra&nbsp; i&nbsp; njihovih&nbsp; pritoka)&nbsp; kao&nbsp; i&nbsp; riparijalnim&nbsp; zonama&nbsp; planinskih&nbsp; i visokoplaninskih&nbsp; oblasti&nbsp; takođe&nbsp; je očekivano&nbsp; da&nbsp; će&nbsp; doći&nbsp; do&nbsp; povećanja&nbsp; broja prisutnih&nbsp; invazivnih&nbsp; vrsta&nbsp; i&nbsp; njihovog daljeg širenja.</p> / <p>Bearing&nbsp; in&nbsp; mind&nbsp; the&nbsp; significance&nbsp; of&nbsp; inland surface waters for the introduction and spread of invasive&nbsp; alien&nbsp; species&nbsp; (IAS),&nbsp; the&nbsp; aims&nbsp; of&nbsp; this research&nbsp; were&nbsp; to&nbsp; present&nbsp; the&nbsp; contemporary records&nbsp; of&nbsp; aquatic&nbsp; invasive&nbsp; plant&nbsp; species&nbsp; in surface&nbsp; waters,&nbsp; analyse&nbsp; the&nbsp; level&nbsp; of&nbsp; invasion&nbsp; of riparian&nbsp; areas&nbsp; in&nbsp; Serbia,&nbsp; determine&nbsp; the&nbsp; habitat preferences&nbsp; of&nbsp; the&nbsp; analysed&nbsp; IAS&nbsp; and&nbsp; determine the effects of different habitat characteristics and anthropogenic&nbsp; influences&nbsp; on&nbsp; the&nbsp; presence&nbsp; and bundance&nbsp; of&nbsp; the&nbsp; 26&nbsp; analysed&nbsp; invasive&nbsp; plants. Field&nbsp; research&nbsp; was&nbsp; conducted&nbsp; during&nbsp; the&nbsp; 2013-2016&nbsp; period.&nbsp; A&nbsp; total&nbsp; of&nbsp; 250&nbsp; field&nbsp; sites&nbsp; were analysed&nbsp; as&nbsp; part&nbsp; of&nbsp; this&nbsp; research,&nbsp; 217&nbsp; in&nbsp; the riparian zones of 39 rivers and 33 in the riparian zones&nbsp;&nbsp;&nbsp; of&nbsp; six&nbsp; canal&nbsp; sections&nbsp; of&nbsp; the&nbsp; hydrosystem Danube-Tisa-Danube&nbsp; (HS&nbsp; DTD).&nbsp; In&nbsp; addition&nbsp; to data on the cover and abundance of the analysed plant species, data on habitat type (following the EUNIS&nbsp; classification),&nbsp; relevant&nbsp; physical&nbsp; and hydromorhological&nbsp; parameters&nbsp; of&nbsp; the&nbsp; studied watercourses&nbsp; and&nbsp; dominant&nbsp; anthropogenic influences an analysed field sites were recorded (following&nbsp; the&nbsp; standard&nbsp; RHS&nbsp; protocol). Statistical&nbsp; data&nbsp; analysis&nbsp; was&nbsp; done&nbsp; in&nbsp; CANOCO 5.0&nbsp;&nbsp; software,&nbsp; using&nbsp; the&nbsp; principal&nbsp; component analysis&nbsp; (PCA),&nbsp; canonical&nbsp; correspondence analysis (CCA) and redundancy analysis (RDA). Eight&nbsp; aquatic&nbsp; invasive&nbsp; plant&nbsp; species&nbsp; were recorded for the territory of Serbia. Species with the highest number of records were:&nbsp; Vallisneria spiralis,&nbsp; Azolla filiculoides&nbsp; and&nbsp; Elodea nuttallii. They&nbsp; are&nbsp; primarily&nbsp; present&nbsp; in&nbsp; running,&nbsp; in comparison&nbsp; with&nbsp; standing&nbsp; waters,&nbsp; and&nbsp; the&nbsp; canal network&nbsp; of&nbsp; the&nbsp; HS&nbsp; DTD&nbsp; and&nbsp; rivers&nbsp; of&nbsp; the Danube catchment area are considered to be their main&nbsp; aquatic&nbsp; corridor&nbsp; of&nbsp; spread.&nbsp; Of&nbsp; the&nbsp; 26 invasive plant taxa whose presence&nbsp; was recorded and&nbsp; analysed&nbsp; in&nbsp; the&nbsp; riparian&nbsp; areas&nbsp; of&nbsp; Serbia,Xanthium strumarium&nbsp; subsp.&nbsp; italicum,&nbsp; Amorpha fruticosa,&nbsp; Erigeron&nbsp; canadensis,&nbsp; Robinia pseudoacacia&nbsp; and&nbsp; Echinochloa&nbsp; crus-&nbsp; galli&nbsp; were taxa&nbsp; with&nbsp; the&nbsp; highest&nbsp; number&nbsp; of&nbsp; records.Catchment&nbsp; areas&nbsp; of&nbsp; the&nbsp; Danube,&nbsp; Južna&nbsp; Morava, Zapadna&nbsp; Morava&nbsp; and&nbsp; Timok&nbsp; rivers&nbsp; were characterised&nbsp; by&nbsp; the&nbsp; highest&nbsp; levels&nbsp; of&nbsp; invasion. Based&nbsp; on&nbsp; their&nbsp; distribution&nbsp; data,&nbsp; cover&nbsp; and abundance of the analysed taxa, catchment areas of&nbsp; the&nbsp; Danube,&nbsp; Kolubara&nbsp; and&nbsp; Zapadna&nbsp; Morava rivers&nbsp; are&nbsp; highlighted&nbsp; as&nbsp; the&nbsp; main&nbsp; corridors&nbsp; of spread for the majority of the studied IAS. Four habitat&nbsp; types&nbsp; stand&nbsp; out&nbsp; by&nbsp; the&nbsp; number&nbsp; of analysed IAS. Taxa which were recorded in the highest&nbsp; number&nbsp; of&nbsp; habitat&nbsp; types&nbsp; are:&nbsp; Amorpha fruticosa,&nbsp; Erigeron&nbsp; canadensis,&nbsp; Robinia pseudoacacia,&nbsp; Echinochloa&nbsp; crus-galli&nbsp; and Xanthium strumarium subsp. italicum.&nbsp; A number of&nbsp; physical&nbsp; and&nbsp; hydromorphological&nbsp; parameters and&nbsp; dominant&nbsp; anthropogenic&nbsp; influences&nbsp; of&nbsp; the studied&nbsp; field&nbsp; sites&nbsp; were&nbsp; shown&nbsp; to&nbsp; affect&nbsp; the presence&nbsp; and&nbsp; abundance&nbsp; of&nbsp; the&nbsp; studied&nbsp; invasive plants.&nbsp; The catchment areas of the Sava, Velika Morava&nbsp; and&nbsp; Južna&nbsp; Morava&nbsp; rivers&nbsp; are&nbsp; excpected to&nbsp; be&nbsp; under&nbsp; a&nbsp; strong&nbsp; pressure&nbsp; of&nbsp; the&nbsp; spread&nbsp; and dominance&nbsp; of&nbsp; IAS&nbsp; unnder&nbsp; the&nbsp; conditions&nbsp; of global&nbsp; climate&nbsp; changes.&nbsp; Riparian&nbsp; areas&nbsp; in&nbsp; the southwestern parts of Serbia (valleys of&nbsp; Lim and Ibar&nbsp; rivers&nbsp; and&nbsp; their&nbsp; tributaries)&nbsp; and&nbsp; riparian zones&nbsp; in&nbsp; the&nbsp; mountain&nbsp; and&nbsp; high- mountain&nbsp; areas are also expected to experience an increase in the number&nbsp; of&nbsp; invasive&nbsp; species&nbsp; and&nbsp; their&nbsp; spread rates.</p>

MENVM / Department of Ecology and Resource Management

MENVSC / Department of Geography and Geo-Information Sciences / Human activities on land degradation have triggered several environmental problems especially in rural areas that are under developed. The main aim of this study is to analyse the contribution of different land uses to gully development and sediment load on the Nzhelele River Valley in the Limpopo Province. Data was collected using different methods such as observation, field data techniques and experiments. Satellite digital images, topographic maps, aerial photographs and the sediment load static model also assisted in determining how land use affects gully development and sediment load. For data analysis, the researcher used the following methods: Analysis of Variance (ANOVA), descriptive statistics, Pearson correlation coefficient and statistical correlation methods. The results of the research illustrates that high land use activities create negative changes especially in areas that are highly fragile and vulnerable. Distinct impact on land use change was observed within settlement area (9.6 %) within a period of 5 years. High correlation between soil organic matter and soil moisture (R=0.96) was observed. Furthermore a significant variation (p ≤ 0.6) between the soil organic matter and soil moisture was also observed. A very significant variation (p ≤ 0.003) was observed in bulk density and extreme significant variations (p ≤ 0.0001) were observed in organic matter and soil particle size. The sand mining and agricultural activities has contributed significantly to the amount of sediment load in the Nzhelele River. A high significant amount of total suspended sediment (55.3 %) and bed load (53.8 %) was observed within the agricultural area. The connection which associates the development of gullies to various land use activities determines the amount of sediment load. These results are consistent with other previous research and suggest that land use activities is likely to exacerbate the development of gullies and sediment load in the Nzhelele River Valley