Ecological Restoration Plan for Palo Laziale Wood, Italy

Project location: ITALY, Palo Laziale
Project start date: October 2010 - Project end date: December 2012
Project number: 2010-39
Beneficiary: Associazione Alsium

 

The Palo Laziale wood together with the wood of the Castel Porziano Presidential Estate  and that of the Circeo National Park represents one of the few remnant examples of Mediterranean planitial forests favored by the superficial water table and characterized by natural ponds. These forest habitats have been drastically reduced because of the expansion of agricultural activities and the urbanization.

In June 1995 the wood of Palo has been identified as Site of Community Importance according to the European Commission Habitats Directive (92/43/EEC). The motivations for this choice lied on the recognition of the good status of conservation of European community priority habitat "3170* - Mediterranean temporary ponds" together with its importance for migratory birds and the rich fauna of arthropods and vertebrates characteristics of the hygrophilous wood.

At the end of 1995 the first records of stresses of tree species, mainly belonging to Quercus genus, were spotted. The following year, a noticeable evidence of an increasing tree mortality occurred. This process continued up today causing the complete collapse of the forest habitat with the death of more than 4000 tree individuals. It has been hypothesized that the concomitant and integrated effects of the increasing drought, the interruption of the traditional silvicultural activities, the lowering of the water table and its salinization could have determined a physiological stress on tree species. This, in turns, made them vulnerable to the attack of phytopatogenous fungi such as Biscogniauxia mediterranea, causal agent of ‘charcoal disease' of Fagaceae and Phytophthora spp. causing severe collar and root rot on Quercus ilex.

Several episodes of oak mortality in many European countries have been reported, however because of the complex underlining spatial and temporal patterns of interacting factors (both abiotic and biotic), the fundamental mechanisms underlying tree survival and mortality during drought remain poorly understood. Moreover temporal patterns of tree mortality also can be difficult to interpret due to lagged responses in some species, in which mortality has been shown to occur years or even decades after stress occurred. We have also to consider that the long-lived nature of trees and their ability to shift allocation of resources and change their hydraulic architecture throughout their lives can result in non-linear responses to t stress in both space and time.

Based on the above considerations, the need for an integrated analysis aimed at clarifying the causes of the collapse of the wood and at identifying the current environmental conditions of the site arises in order to identify the best restoration intervention. This activity is also urgent because the occurred degradation process severely impacted the environmental quality of the Site of Community Importance of whose conservation the Lazio Region is responsible.

In particular the following tasks will be performed:

-         Identify drought events occurred in the last decades and quantify the changes of temperature and precipitation regimes.

-         Analyze the land use change and quantify the increase of the surrounding human pressure.

-         Evaluate the physical-chemical characteristic and dynamics of the water table aquifer with specific focus on salinization processes.

-         Analyze the current paedological characteristics of the site.

-         Evaluate the effects of the recent selvicultural change.

-         Analyze the current dynamic processes of the vegetation and the capacity of regeneration of tree species in order to forecast potential trends of the forest habitat.

-         Evaluate the status of the pathogen attacks associated and involved in forest decline.

-         Compare the environmental characteristics of the Palo wood with similar areas such as the forest of the Circeo National Park and that of the Castel Porziano Presidential Estate.

Together with the study, a plant nursery has to be created in order to grow seedlings of several tree species for the future reforestation. The tree species have to be chosen according to the firsts results of the study and a preliminary and limited reforestation will be conducted in order to obtain indications on the capacity of regeneration of species.

 

Activities Timetable:

Action	Start date	End date	Responsible
Collection of all the available information	1 February 2011	31th March 2011	All participants
Hydrological analysis	1th February 2011	31 January 2012	UNIROMADST
Phytopatological analysis	1th February 2011	30 October 2011	UNITUS
Soil analysis	1th March 2011	30 June 2011	UNIROMADBV
Vegetation analysis	1th March 2011	30 July 2011	UNIROMADBV
Creation of a Plant Nursery for the cultivation of seedlings of tree species	1 April 2011	30 June 2011	UNIROMADBV
Presentation of the SIC Management plan to the Lazio region	1 February 2011	30 June 2011	UNIROMADBV
Elaboration of the final report about the environmental analyses	1 December 2011	31 December 2011	All participants
Elaboration of the restoration plan	15 January 2012	28 February 2012	All participants
Project time frame	1 February 2011	29' February 2012	All participants

 

This project received a grant from the Nando Peretti Foundation to achieve the following goals:

-       Identification of the interacting factors and ecological mechanisms responsible for the decline and mortality of this and other similar forest habitats.

-       Elaboration of conservation strategies to prevent future tree die-off.

-       Elaboration of a restoration plan that takes into consideration the current and future predicted environmental conditions (i.e. climate change and increasing drought and warmer temperatures.

-       Implementation of restoration actions to be undertaken in a step by step approach according to an adaptive strategy. These actions may include the creation of small artificial ponds for irrigation, a structure for the cultivation of seedlings, plantation of seedlings according to the environmental/topographical gradients of the area.