Forest cover and its change in Unguja Island, Zanzibar

Tropical forests are sources of many ecosystem services, but these forests are vanishing rapidly. The situation is severe in Sub-Saharan Africa and especially in Tanzania. The causes of change are multidimensional and strongly interdependent, and only understanding them comprehensively helps to change the ongoing unsustainable trends of forest decline. Ongoing forest changes, their spatiality and connection to humans and environment can be studied with the methods of Land Change Science. The knowledge produced with these methods helps to make arguments about the actors, actions and causes that are behind the forest decline. In this study of Unguja Island in Zanzibar the focus is in the current forest cover and its changes between 1996 and 2009. The cover and changes are measured with often used remote sensing methods of automated land cover classification and post-classification comparison from medium resolution satellite images. Kernel Density Estimation is used to determine the clusters of change, sub-area –analysis provides information about the differences between regions, while distance and regression analyses connect changes to environmental factors. These analyses do not only explain the happened changes, but also allow building quantitative and spatial future scenarios. Similar study has not been made for Unguja and therefore it provides new information, which is beneficial for the whole society. The results show that 572 km2 of Unguja is still forested, but 0,82–1,19% of these forests are disappearing annually. Besides deforestation also vertical degradation and spatial changes are significant problems. Deforestation is most severe in the communal indigenous forests, but also agroforests are decreasing. Spatially deforestation concentrates to the areas close to the coastline, population and Zanzibar Town. Biophysical factors on the other hand do not seem to influence the ongoing deforestation process. If the current trend continues there should be approximately 485 km2 of forests remaining in 2025. Solutions to these deforestation problems should be looked from sustainable land use management, surveying and protection of the forests in risk areas and spatially targeted self-sustainable tree planting schemes.Siirretty Doriast

Mapping Natural Forest Remnants with Multi-Source and Multi-Temporal Remote Sensing Data for More Informed Management of Global Biodiversity Hotspots

Global terrestrial biodiversity hotspots (GBH) represent areas featuring exceptional concentrations of endemism and habitat loss in the world. Unfortunately, geospatial data of natural habitats of the GBHs are often outdated, imprecise, and coarse, and need updating for improved management and protection actions. Recent developments in satellite image availability, combined with enhanced machine learning algorithms and computing capacity, enable cost-efficient updating of geospatial information of these already severely fragmented habitats. This study aimed to develop a more accurate method for mapping closed canopy evergreen natural forest (CCEF) of the Eastern Arc Mountains (EAM) ecoregion in Tanzania and Kenya, and to update the knowledge on its spatial extent, level of fragmentation, and conservation status. We tested 1023 model possibilities stemming from a combination of Sentinel-1 (S1) and Sentinel-2 (S2) satellite imagery, spatial texture of S1 and S2, seasonality derived from Landsat-8 time series, and topographic information, using random forest modelling approach. We compared the best CCEF model with existing spatial forest products from the EAM through independent accuracy assessment. Finally, the CCEF model was used to estimate the fragmentation and conservation coverage of the EAM. The CCEF model has moderate accuracy measured in True Skill Statistic (0.57), and it clearly outperforms other similar products from the region. Based on this model, there are about 296,000 ha of Eastern Arc Forests (EAF) left. Furthermore, acknowledging small forest fragments (1-10 ha) implies that the EAFs are more fragmented than previously considered. Currently, the official protection of EAFs is disproportionally targeting well-studied mountain blocks, while less known areas and small fragments are underrepresented in the protected area network. Thus, the generated CCEF model should be used to design updates and more informed and detailed conservation allocation plans to balance this situation. The results highlight that spatial texture of S2, seasonality, and topography are the most important variables describing the EAFs, while spatial texture of S1 increases the model performance slightly. All in all, our work demonstrates that recent developments in Earth observation allows significant enhancements in mapping, which should be utilized in areas with outstanding biodiversity values for better forest and conservation planning.Peer reviewe

Urban expansion in Zanzibar City, Tanzania : Analyzing quantity, spatial patterns and effects of alternative planning approaches

Rapid urbanization and urban area expansion of sub-Saharan Africa are megatrends of the 21st century. Addressing environmental and social problems related to these megatrends requires faster and more efficient urban planning that is based on measured information of the expansion patterns. Urban growth prediction models (UGPMs) provide tools for generating such information by predicting future urban expansion patterns and allowing testing of alternative planning scenarios. We created an UGPM for Zanzibar City in Tanzania by measuring urban expansion in 2004-2009 and 2009-2013, linking the expansion to explanatory variables with a generalized additive model, measuring the accuracy of the created model, and projecting urban growth until 2030 with the business-as-usual and various alternative planning scenarios. Based on the results, the urban area of Zanzibar City expanded by 40% from 2004 to 2013. Spatial patterns of expansion were largely driven by the already existing building pattern and land-use constraints. The created model predicted future urban expansion moderately well and had an area under the curve value of 0.855 and a true skill statistic result of 0.568. Based on the business-as-usual scenario, the city will expand 89% from 2013 until 2030 and will continue to sprawl to new regions at the outskirts of the current built-up area. Establishing new urban centers had the highest impact on directing urban expansion from the tested alternative planning scenarios. However, the impact of all scenarios was low and therefore also other planning solutions such as vertical development, urban growth boundaries, and gradual improvement of the informal areas should be considered in Zanzibar.Peer reviewe

Mapping Natural Forest Remnants with Multi-Source and Multi-Temporal Remote Sensing Data for More Informed Management of Global Biodiversity Hotspots

Global terrestrial biodiversity hotspots (GBH) represent areas featuring exceptional concentrations of endemism and habitat loss in the world. Unfortunately, geospatial data of natural habitats of the GBHs are often outdated, imprecise, and coarse, and need updating for improved management and protection actions. Recent developments in satellite image availability, combined with enhanced machine learning algorithms and computing capacity, enable cost-efficient updating of geospatial information of these already severely fragmented habitats. This study aimed to develop a more accurate method for mapping closed canopy evergreen natural forest (CCEF) of the Eastern Arc Mountains (EAM) ecoregion in Tanzania and Kenya, and to update the knowledge on its spatial extent, level of fragmentation, and conservation status. We tested 1023 model possibilities stemming from a combination of Sentinel-1 (S1) and Sentinel-2 (S2) satellite imagery, spatial texture of S1 and S2, seasonality derived from Landsat-8 time series, and topographic information, using random forest modelling approach. We compared the best CCEF model with existing spatial forest products from the EAM through independent accuracy assessment. Finally, the CCEF model was used to estimate the fragmentation and conservation coverage of the EAM. The CCEF model has moderate accuracy measured in True Skill Statistic (0.57), and it clearly outperforms other similar products from the region. Based on this model, there are about 296,000 ha of Eastern Arc Forests (EAF) left. Furthermore, acknowledging small forest fragments (1–10 ha) implies that the EAFs are more fragmented than previously considered. Currently, the official protection of EAFs is disproportionally targeting well-studied mountain blocks, while less known areas and small fragments are underrepresented in the protected area network. Thus, the generated CCEF model should be used to design updates and more informed and detailed conservation allocation plans to balance this situation. The results highlight that spatial texture of S2, seasonality, and topography are the most important variables describing the EAFs, while spatial texture of S1 increases the model performance slightly. All in all, our work demonstrates that recent developments in Earth observation allows significant enhancements in mapping, which should be utilized in areas with outstanding biodiversity values for better forest and conservation planning.</p

Towards Operational Monitoring of Forest Canopy Disturbance in Evergreen Rain Forests : A Test Case in Continental Southeast Asia

This study presents an approach to forest canopy disturbance monitoring in evergreen forests in continental Southeast Asia, based on temporal differences of a modified normalized burn ratio (NBR) vegetation index. We generate NBR values from each available Landsat 8 scene of a given period. A step of ' self-referencing' normalizes the NBR values, largely eliminating illumination/topography effects, thus maximizing inter-comparability. We then create yearly composites of these self-referenced NBR (rNBR) values, selecting per pixel the maximum rNBR value over each observation period, which reflects the most open canopy cover condition of that pixel. The ArNBR is generated as the difference between the composites of two reference periods. The methodology produces seamless and consistent maps, highlighting patterns of canopy disturbances (e. g., encroachment, selective logging), and keeping artifacts at minimum level. The monitoring approach was validated within four test sites with an overall accuracy of almost 78% using very high resolution satellite reference imagery. The methodology was implemented in a Google Earth Engine (GEE) script requiring no user interaction. A threshold is applied to the final output dataset in order to separate signal from noise. The approach, capable of detecting sub-pixel disturbance events as small as 0.005 ha, is transparent and reproducible, and can help to increase the credibility of monitoring, reporting and verification (MRV), as required in the context of reducing emissions from deforestation and forest degradation (REDD+).Peer reviewe

Elvytys : KÄYPÄ HOITO -SUOSITUS (Päivitystiivistelmä)

Käypä hoito -suositus. Päivitystiivistelmä. English abstrac

Modeling direct above-ground carbon loss due to urban expansion in Zanzibar City Region, Tanzania

Expansion of urban fabric on carbon storages is estimated to cause loss of 1.38 Pg of Above-Ground Carbon (AGC) in pan-tropics between 2000 and 2030. This would be approximately 5% of all emissions caused by tropical land use changes. Despite the significance of the phenomenon, these emissions are rarely measured, monitored, or addressed in climate change mitigation plans, especially in Sub-Saharan Africa. Therefore, we demonstrated a state-of-the-art approach predicting AGC loss of Zanzibar City Region under multiple alternative urban planning scenarios between 2013 and 2030. The AGC information was modeled based on field measured forest inventory sample plots and RapidEye satellite data from 2013, while the future urban expansion model was calibrated with data of happened expansion between 2004, 2009 and 2013, and geospatial independent variables influencing the expansion patterns. This model was then projected until 2030, while alternative urban planning scenarios were integrated to the model by modifying the geospatial variables. The combination of these two models indicates that 42,000 Mg or 15% of total AGC in Zanzibar City Region can be anticipated to be lost by 2030 due to urban expansion. Majority of the loss will take place in the agroforest and fruit tree plantations surrounding the city, while natural forest face limited impacts. None of the tested alternative urban planning scenarios significantly impact the loss of AGC compared to the business-as-usual scenario. Therefore, alternative policies and plans are seriously needed to address the issue in Zanzibar. These could include promoting urban densification, directing urban expansion to low carbon areas, improving soil carbon management, and preparing an urban forestry and greenery strategy. All in all, the study indicates that data and methods are available for monitoring and predicting the phenomenon in Sub-Saharan Africa. Research based on a comparable methodology should be produced from all the main cities in the region that are surrounded by significant carbon storages and facing high urban expansion rates to support climate change mitigation.</p

Metsäjärvien tila ja tulevaisuus

Pohjois-Karjalan ympäristökeskuksessa vuonna 2004 käynnistetyn ”Pohjois-Karjalan vesistöjen tilan parantaminen” – hankkeen tavoitteena oli selvittää 16 pohjoiskarjalaisen, hajakuormituksen rasittaman metsäjärven ekologista tilaa, siihen vaikuttavia tekijöitä sekä arvioida järvien kunnostustarvetta. Ekologisen tilan arvio tehtiin kasviplanktonin, pohjaeläinten, vesikasvien ja/tai kalaston perusteella. Veden laadun kehitystä selvitettiin pohjasedimentin piilevien avulla. Vedenlaatuun vaikuttavina tekijöinä määritettiin valuma-alueen maankäyttö ja kuormitus sekä järven ominaispiirteet. Tulosten mukaan hankejärvistä suurin osa oli erinomaisessa tai vähintään hyvässä kunnossa, joskin järvien ekologisen tilan arvio saattoi eri biologisten luokittelutekijöiden välillä vaihdella huomattavastikin. Vuonna 2000 hyväksytty Euroopan unionin vesipuitedirektiivi (EU 2000) velvoittaa vesien hyvää tilaa vuoteen 2015 mennessä. Pohjoisen havumetsävyöhykkeen biologisesti ainutlaatuisen ja monimuotoisen vesiluonnon säilymisen edellytyksenä on vesiensuojelun huomioiminen valuma-alueella suunniteltaessa ja toteutettaessa maankäyttöön liittyviä toimenpiteitä. Oirehtivilla metsäjärvillä ja niiden valuma-alueilla tulisi myös kunnostustoimenpiteet aloittaa heti

Selvitys työturvallisuudesta - Häirintä etä-asiakaspalvelussa

Etäasiakaspalvelussa tapahtuvasta häirinnästä ei ole Suomessa tehty ilmiön laajuutta tai muita ulottuvuuksia koskevaa selvitystä. Tarkoituksena oli tuottaa tilannekuvaa työntekijöiden kohtaamasta häirinnästä eri toimialoilla etäasiakasrajapinnassa. Opinnäytetyön tavoitteena oli tuottaa lisäarvoa toimeksiantajana toimineelle Asiakkuusmarkkinointiliitolle. Opinnäytetyötä kehystää kirjallisuuskatsauksen kautta rakennettu tietoperusta, jossa käsitellään häirintäteemaa siihen liittyvien käsitteiden, artikkeleiden, julkaisujen ja tutkimuksien avulla. Aineistonkeruumenetelmänä toimi kysely, joka lähetettiin toimeksiantajan asiakasyritykselle. Kyselyyn osallistui 17 asiakasyritystä. Aineiston analysointimenetelmänä käytettiin tilastollisesti kuvaavaa analyysiä. Opinnäytetyön tulosten perusteella asiakkaiden harjoittama häirintä on vakiintunut osaksi etäasiakaspalvelun työympäristöä ja sen trendi on kasvussa. Häirinnällä koetaan olevan negatiivisia vaikutuksia työntekijöihin ja siitä raportoimisen ei koettu olevan tarpeeksi riittävällä tasolla, vaikka häirintätilanteita varten oli menettelyohjeita ja koulutusta