Village Tank Cascade System (VTCS) landscapes in the dry zone of Sri Lanka provide multiple ecosystem services (ESs) and benefits to local communities, sustaining the productivity of their land use systems (LUSs). However, there is a lack of adequate scientific research on the ESs of LUSs, despite the recent land use changes that have greatly impacted the provisioning of ESs. Collection of baseline ESs data is a pre-requisite for decision making on ESs-based ecological restoration and management of the VTCS. Thus, this study aimed at assessing ESs of the Mahakanumulla VTCS (MVTCS) located in the Anuradhapura district of Sri Lanka by using a participatory approach involving the integration of local knowledge, expert judgements and LUSs attribute data to assess the ESs. The methodology was designed to integrate the biodiversity and land degradation status of LUSs in a way that is directly linked with the supply of ESs. The study identified twenty-four ESs of the MVTCS based on community perceptions. The identified ESs were assessed as a function of LUSs to develop an ecosystem service supply (ESS) and demand (ESD) matrix model. The results reveal that the current overall ESD for regulating and supporting ESs is higher than the ESS capacity of MVTCS. The assessment also revealed that land degradation and biodiversity deterioration reduce the capacity to provide ESs. Downstream LUSs of the meso-catchment were found to be more vulnerable to degradation and insufficient to provide ESs. Further, the study established that ESs in the MVTCS are generated through direct species-based and biophysical-based providers. In addition, it emerged that social and cultural engagements also played an important role in association with both providers to generate certain types of ESs. Therefore, it can be concluded that VTCS ecological restoration depends on the extent to which integrated effort addresses the levels of ecological complexity, as well as the social engagement of communities and stakeholders. The results of this study provide a scientific basis that can inform future land use decision making and practices that are applicable to successful ESs-based ecological restoration and management of the VTCSs in the dry zone of Sri Lanka.

Invasive alien plant species (IAPS) have had a significant impact on agriculture in many countries in the world. Climatic suitability maps can be used to assess the vulnerability of agricultural areas for potential plant invasions. We used climatic suitability heat maps of IAPS to examine how potential climatic suitability for multiple IAPS invasion changes in eight agricultural land-use types in Sri Lanka under climate change scenarios for 2050. The findings of the study revealed that all evaluated agricultural land-use types are potentially vulnerable to invasion by different numbers of IAPS. In the majority of land-use types, the climatic suitability for multiple IAPS was predicted to increase under climate change scenarios. Out of all land-use types, coconut grown areas are expected to have the greatest suitability increase for more than three IAPS. Nearly all paddy lands were predicted to become suitable for two serious aquatic invaders (Eichhornia crassipes and Salvinia molesta) under current climatic conditions. However, a noticeable reduction in climatic suitability for IAPS was predicted in paddy lands by 2050. The study provides useful information that can be used by policy-makers to develop effective control and management strategies against the establishment of IAPS in agricultural land-uses in Sri Lanka.