Lennox Gareth D, Fargione Joseph, Spector Sacha, Williams Gwyn, Armsworth Paul R
Lancaster Environment Centre, Lancaster University, Lancaster LA1, 4YQ, U.K.
The Nature Conservancy, 1101 West River Parkway, Suite 200, Minneapolis, MN, 55415, U.S.A.
Conserv Biol. 2017 Jun;31(3):666-674. doi: 10.1111/cobi.12771. Epub 2017 Mar 20.
Land-acquisition strategies employed by conservation organizations vary in their flexibility. Conservation-planning theory largely fails to reflect this by presenting models that are either extremely inflexible-parcel acquisitions are irreversible and budgets are fixed-or extremely flexible-previously acquired parcels can readily be sold. This latter approach, the selling of protected areas, is infeasible or problematic in many situations. We considered the value to conservation organizations of increasing the flexibility of their land-acquisition strategies through their approach to financing deals. Specifically, we modeled 2 acquisition-financing methods commonly used by conservation organizations: borrowing and budget carry-over. Using simulated data, we compared results from these models with those from an inflexible fixed-budget model and an extremely flexible selling model in which previous acquisitions could be sold to fund new acquisitions. We then examined 3 case studies of how conservation organizations use borrowing and budget carry-over in practice. Model comparisons showed that borrowing and budget carry-over always returned considerably higher rewards than the fixed-budget model. How they performed relative to the selling model depended on the relative conservation value of past acquisitions. Both the models and case studies showed that incorporating flexibility through borrowing or budget carry-over gives conservation organizations the ability to purchase parcels of higher conservation value than when budgets are fixed without the problems associated with the selling of protected areas.
保护组织采用的土地收购策略在灵活性方面各不相同。保护规划理论在很大程度上未能反映这一点，它所呈现的模型要么极其缺乏灵活性——地块收购不可逆转且预算固定，要么极其灵活——先前收购的地块可以随时出售。后一种方法，即出售保护区，在许多情况下是不可行的或存在问题的。我们考虑了保护组织通过其融资交易方式提高土地收购策略灵活性的价值。具体而言，我们对保护组织常用的两种收购融资方法进行了建模：借款和预算结转。使用模拟数据，我们将这些模型的结果与一个缺乏灵活性的固定预算模型以及一个极其灵活的出售模型（在该模型中，先前的收购可以出售以资助新的收购）的结果进行了比较。然后，我们研究了3个保护组织在实践中如何使用借款和预算结转的案例研究。模型比较表明，借款和预算结转总是比固定预算模型带来更高的回报。它们相对于出售模型的表现取决于过去收购的相对保护价值。模型和案例研究均表明，通过借款或预算结转纳入灵活性，使保护组织能够购买比预算固定时具有更高保护价值的地块，同时避免了与出售保护区相关的问题。
