Species-specific biomass allometric models and expansion factors for indigenous and planted forests of the Mozambique highlands

Secondary Miombo woodlands and forest plantations occupy increasing areas in Mozambique,the former due to anthropogenic activities.Plantations,mainly species of Eucalyptus and Pinus,are being established on sites previously covered by secondary Miombo woodlands.This affects the evolution,cycle and spatiotemporal patterns of carbon(C)storage and stocks in forest ecosystems.The estimation of C storage,which is indispensable for formulating climate change policies on sequestrating CO_(2),requires tools such as biomass models and biomass conversion and expansion factors(BCEF).In Mozambique,these tools are needed for both indigenous forests and plantations.The objective of this study is to fit species-specific allometric biomass models and BCEF for exotic and indigenous tree species.To incorporate efficient inter-species variability,biomass equations were fitted using nonlinear mixed-effects models.All tree component biomass models had good predictability;however,better predictive accuracy and ability was observed for the 2-predictors biomass model with tree height as a second predictor.The majority of the variability in BCEF was explained by the variation in tree species.Miombo species had larger crown biomass per unit of stem diameter and stored larger amounts of biomass per stem volume.However,due to relatively rapid growth,larger stem diameters,heights,and stand density,the plantations stored more biomass per tree and per unit area.

Mapping Landscape Positions and Relevance of Two Dambo-Springs in Incalaue River Basin in Niassa Special Reserve,Mozambique:Information for Drought Water Shortage Effects Management

Mapping of topography and land use/cover as well as spring water yield measurements were done for 2 dambo-spring fed micro-catchments in Incalaue river catchment.The springs are located near Ntimbo 1 and Lizongole human settlement areas in Niassa Special Reserve(NSR).Community consultations were used to asses locally perceived knowledge of dambo-spring catchments dependence by these communities and wildlife;as well as changes and experiences.The Ntimbo 1 dambo-spring catchment(26.55 sq.km)has elevation gradient of 310 to 530 m a.s.l;and the area can topographically be linked to Incalaue river by delineation from a 90-meter spatial resolution Digital Elevation Model(DEM).The Lizongole dambo-spring catchment(1.33 sq.km)has elevation gradient of 300 to 360 m a.s.l and cannot easily be delineated from 90-meter DEM.Both catchments have the 6 vegetation classes existing in the area as well as farmlands and human settlement areas.There exists potential for wildlife-human water source conflict due to dambo dependence by humans and wildlife in the dry season.Ntimbo dambo-spring had a higher water yield per second than the Lizongole dambo-spring.There was no significant difference in spring yields of Ntimbo and Lizongole in the dry season(P<0.05).The Lizongole spring could not be gauged in the wet season because of the wet dambo valley wetland location.There was no significant reduction in water yield for Ntimbo spring during the dry season(P<0.05).The study suggests that Ntimbo spring could be from a confined aquifer;and Lizongole spring to be from a shallow unconfined aquifer.This study contributes understanding of the poorly-defined dambo areas by adding the role of groundwater in supporting micro-dambos which support herbaceous flora and graminivorous fauna as well as human populations in Incalaue basin in NSR especially in the dry season.

Proposing Land Use/Cover Conservation Basing on Connectivity,Changes and Drivers over 20 Years in Incalaue River Basin,Niassa National Reserve in Mozambique

Landscape heterogeneity in biodiversity conservation areas can be represented by the size of the geographic range of vegetation cover types and their species composition;and is reflected in historical and contemporary LULC(Land Use/Cover).This study assesses LULC changes in a predominantly vegetated Incalaue river basin in NSR(Niassa Special Reserve)for the years 2001,2009 and 2019 to recommend conservation targets.LULC was mapped using the best available Landsat imagery of the area which were L7 EMT+(Landsat 7 Enhanced Thematic Mapper),L5 TM(Landsat 5 Thematic Mapper)and L8 OLI(Landsat 8 Operational Land Imagery).Image classification and remote sensing analysis were done using images of 30-meter resolution using the maximum likelihood supervised classification on ArcGIS ArcMap 10.4.1.Results showed that there were gains in area coverfor taller vegetation classes with the major ones being MDW(Medium Density Woodland)which increased by 51.07%;MFS(Mountain Forests)by 36.41%;and HDW(High-Density Woodland)by 17.95%over the studied period.NDVI(Normalized Difference Vegetation Index)maps show 2019 with wetter vegetation than 2001;and both wetter than 2009.The spatially dominant vegetation-class was MDW(Medium Density Woodland)covering 27.29%of the basin area largely in the elevation band 410-430 m a.s.l.Vegetation classes do not necessarily follow landform with rocky upstream section(440-510 m a.s.l)having MFS which also existed in lower altitude areas(370-430 m a.s.l);and woodland being randomly distributed across the basin while there was also WET(Wetland)in both upstream and downstream.There are multiple vegetation species localized in distribution in the landscape which makes these to be hotspot areas for conservation.Local people in the human settlement areas of Ntimbo 1 and Lizongole recognize vulnerability of ecosystems,environmental change as well as human land use/cover and climate change as the main threats.There was a large increase in human settlement area(104.17%)over the study period and this shows a need for mitigating community-wildlife conflict especially along the green vegetation riverine areas during the dry seasons.The study showed need for a plan for human LULC away from wildlife vegetation hotspot areas;identification and consideration of area-demanding threatened species that require landscape scale conservation;and prevention of degradation and loss of water source hotspots for wildlife as well as conservation of sensitive and localized vegetation species.The Mozambican land law allows individual ownership of land by citizens even in conservation areas which creates a danger of human-wildlife interactions;risks land encroachment deeper into the reserve;and potentially causing environmentaldegradingof this sensitive ecosystem hosting humans and wildlife so there is need for consistent and conservation targetedenvironmental research to inform policy and LULC decisions.